Information theory and linguistic structuring

Communication depends upon the reciprocal interpretation of meaning, by speaker and listener, and meaning depends upon the structure of the message.     

Sequence-length variation of mtDNA HVS-I C-stretch in Chinese ethnic groups

The purpose of this study was to investigate mitochondrial DNA (mtDNA) hypervariable segment-I (HVS-I) C-stretch variations and explore the significance of these variations in forensic and population genetics studies. The C-stretch sequence variation was studied in 919 unrelated individuals from 8 Chinese ethnic groups using both direct and clone sequencing ap-proaches. Thirty eight C-stretch haplotypes were identified, and some novel and population specific haplotypes were also detected. The C-stretch genetic diversity (GD) values were relatively high, and probability (P) values were low. Additionally, C-stretch length heteroplasmy was observed in approximately 9% of individuals studied. There was a significant correlation (r=-0.961, P<0.01) between the expansion of the cytosine sequence length in the C-stretch of HVS-I and a reduction in the number of up-stream adenines. These results indicate that the C-stretch could be a useful genetic maker in forensic identification of Chinese populations. The results from the Fst and dA genetic distance matrix, neighbor-joining tree, and principal component map also suggest that C-stretch could be used as a reliable genetic marker in population genetics.     

Comparison of accelerometer cut points to estimate physical activity in US adults

Abstract

The purpose of this study was (1) to describe physical activity prevalence, categorised according to the 2008 Physical Activity Guidelines for Americans (2008 Guidelines), using different accelerometer cut points and (2) to examine physical activity prevalence patterns by reported cut points across selected characteristics. Cut points from 9 studies were used to estimate physical activity prevalence in a national adult sample (n = 6547). Estimates were stratified by validation study activity protocols used to derive cut points – ambulatory (walking/running) and lifestyle activities (e.g. gardening, housework, walking). Results showed that the prevalence of meeting the 2008 Guidelines ranged from 6.3% to 98.3% overall and was lower for cut points derived from ambulatory (median = 11.5%, range = 6.3–27.4%) compared to lifestyle (median = 77.2%, range = 60.6–98.3%) protocols. Prevalence patterns across protocols differed for age, but were similar for other characteristics. In conclusion, prevalence of meeting the 2008 Guidelines varied widely, indicating that choice of cut point had an impact on prevalence. To generate future accelerometer cut points one may consider developing cut points for demographic subgroups using a variety of lifestyle physical activities.     

Variability and progression in competitive performance of Paralympic swimmers

Abstract

Analysis of variability and progression in performance of top athletes between competitions provides information about performance targets that is useful for athletes, practitioners, and researchers. In this study, 724 official finals times were analysed for 120 male and 122 female Paralympic swimmers in the 100-m freestyle event at 15 national and international competitions between 2004 and 2006. Separate analyses were performed for males and females in each of four Paralympic subgroups: S2–S4, S5–S7, S8–S10 (most through least physically impaired), and S11–S13 (most through least visually impaired). Mixed modelling of log-transformed times, with adjustment for mean competition times, was used to estimate variability and progression. Within-swimmer race-to-race variability, expressed as a coefficient of variation, ranged from 1.2% (male S5–S7) to 3.7% (male S2–S4). Swimming performance progressed by approximately 0.5% per year for males and females. Typical variation in mean performance time between competitions was ～1% after adjustment for the ability of the athletes in each competition, and the Paralympic Games was the fastest competition. Thus, taking into account variability, progression, and level of competition, Paralympic swimmers who want to increase substantially their medal prospects should aim for an annual improvement of at least 1–2%.     

Slouching towards a mass system: society,government and institutions in the United Kingdom

The paper describes and analyses postwar changes in regulatory and classificatory relationships between British governments and higher education institutions, in the context of broad social, economic and political change, in three time periods. The first, from 1945 to 1970, was marked by consolidation, increased government support, growth in numbers of institutions and students and a broad consensus around the desirability of expansion. The second, from 1970 to 1987, was marked by political hostility and, until 1983, stagnation in the rates of demand for places by students and for graduates by employers. The third period, from 1987 to the present day, suggests that Britain is now committing itself, whether deliberately or not, to a system of mass higher education, with a series of radical changes in government-higher education relationships. In conclusion the paper discusses alternative theoretical approaches to interpreting these developments: Trow's typology of elite-massuniversal higher education and its implications for transition between types; Teichler's analysis of models of higher education structure; and a possible synthesis between the two. But all such models need to pay due attention to the internal processes of higher education at the level of departmental and even individual behavior.     

Urban exploration: Secrecy and information creation and sharing in a hobby context

Urban exploration is a hobby that involves visiting and capturing visual images of urban infrastructure often no longer used, including sewers, towers, factories, and military instalments. Hobbyists then frequently share their visual content via social media sites. The urban explorer's multi-layered construction of content offers an important opportunity to understand how people create information and share experiences and content in a hobby context. Data were gathered through face-to-face interviews with 17 urban explorers from Ireland and the United Kingdom and an analysis of urban explorers' digital presence. Results suggest that urban explorers believe their hobby serves both personal and civic purposes. Urban explorers' creative hobby behaviors further lead them to secretive information behaviors.