Modeling and predicting heart rate dynamics across a broad range of transient exercise intensities during cycling

Prior studies have investigated heart rate dynamics from a variety of perspectives, but are often inadequate for predicting heart rate responses across a broad range of transient exercise intensities. The aim of this study was to develop a nonlinear model to describe the heart rate response of an individual during cycling and to investigate whether heart rate is more accurately predicted by a combination of power output and cadence than by power output alone. The proposed model can account for the transient fluctuations of an individual’s heart rate while they participate in exercise that varies in intensity. The participants for this study each performed a fifty minute bout of cycling on an electric-braked cycle ergometer in the laboratory. The testing protocol for the cycling bout was designed to challenge the predictive capabilities of the model and the participants therefore abruptly changed their power outputs and cadences throughout the tests, which resulted in significant transient fluctuations in their heart rate responses. Due to the nonlinear nature of the proposed heart rate model, a heuristic algorithm was developed to perform the parameter estimation. The model predictions for heart rate matched very well with the experimental heart rate responses for each of the participants, especially when considering the challenges inherent to predicting abrupt transient behavior in the heart rate response. Model comparisons also indicated that heart rate is more accurately predicted by a combination of power output and cadence than by power output alone.     

Phoneme awareness and pathways into literacy: A comparison of German and American children

Where American kindergartners are taughtletters and letter sounds, Germankindergartners are not; where American firstand second graders receive an eclectic blend ofwhole language, whole word and phonics-basedapproaches, their German counterparts aretaught by an intensive synthetic phonicsapproach. As a probe to the consequences ofthese pedagogical differences on the emergenceof phoneme awareness, this study administeredtwo tests of phoneme awareness tokindergarten-, first- and second-grade childrenin Germany and America, along with readingtests, the digit span test and a test of RANcolor naming ability. The American kindergartenchildren excelled on a phoneme identityjudgement and a phoneme deletion task that theGerman kindergartners found difficult. Theiradvantage held equally whether the manipulatedsound was a syllable onset or the initial partof a consonant cluster. The first and secondgraders surpassed the kindergartners in bothcountries; however, the German first and secondgraders equaled their American peers on bothtasks and both types of units. In addition,the German children were more accurate decodersof pseudowords by the end of second grade, andthe association between phoneme awareness andGerman decoding ability was weaker. Anincreased emphasis on phonics and the greatertransparency of the German alphabet arediscussed as possible factors in the decodingexcellence of the German second graders and itsdecreased association with phoneme awareness.The contrast between the American and Germankindergartners and the equivalence of the firstand second graders in the two countries areconsistent with a view that phoneme awarenessdevelops primarily as a product of literacyexposure.     

Time sampling: a methodological critique

Numerous developmental studies of social behavior employ an observational technique called time sampling. This technique is used to estimate the frequencies and proportions of time that actual behaviors occur and to measure group or individual differences. By contrasting time sampling to continuous sampling, we demonstrate that (a) time sampling is inaccurate for estimating actual durations or frequencies of behavior, and (b) resulting individual and/or group differences can change depending on whether time sampling or continuous sampling is used. Error rates are particularly high when the total bout lengths of the actual behaviors are short (as in mother-infant interactions) and/or when interval length is long. Because the majority of mother and infant behaviors are short in bout length (less than 60 sec), when percent error is the greatest, we suggest that alternative sampling methods that have proven validity be used in future studies (e.g., scan, point, or continuous sampling).     

The ‘Employer Engagement Cycle’ in Secondary Education: analysing the testimonies of young British adults

Work experience placements are mandatory in the UK for all young people aged 16–18 in education, and their employability effects and associated wage premia are well noted in the literature. Through Bourdieu’s lens, this article analyses and conceptualises a unique data set of reflective testimonies submitted in response to a YouGov survey of over one thousand young people. Different capitals are detected, their distributions are observed, and correlations with key variables such as social background and school type are reported. Emerging through young people’s perceptions of employer engagement is a complex web of human, social and cultural capital accumulation. Overlaps are frequent, with newly acquired forms of capital often activating others. We argue that because of the cyclical nature of employer engagement gains, benefits accumulate exponentially for some young people while leaving others increasingly detached from the capitals that are most important for labour market success.     

From here to there and back again: the story of a mother,her son,disability, and school choice

Nelly and her children live in Queensland, Australia. When it came time for her second youngest son to start school, Nelly was not prepared for the difficulty that she had enrolling him at the school of her choice. In spite of her son's disability, Nelly thought that it was natural that he would go to his local school with his sister. It is not surprising that she expected this, given the legal and policy endorsement of inclusive education that exists in the Queensland education system. What unfolded in Nelly's life as she pursued this enrolment is the subject of this article. This is the story of a mother who believed in and hoped for inclusive schooling for her son but who found herself caught in a series of events and experiences which ultimately led to the decision to transfer him into a special school. This is also the story of how, disillusioned and regretful, she went on to undo that decision. Told primarily in Nelly's own words, this narrative provides a deep insight into one mother's efforts to exercise her parental authority, the difficulties she encountered in trying to do so, and the consequences for her son.