Effects of radiant heat exposure on pacing pattern during a 15-km cycling time trial

Abstract

The goal of this study was to investigate the effects of different durations of skin temperature manipulation on pacing patterns and performance during a 15-km cycling time trial. Nineteen well-trained men completed three 15-km cycling time trials in 18°C and 50% relative humidity with 4.5-km (short-heat), 9.0-km (long-heat) or without (control) radiant heat exposure applied by infrared heaters after 1.5 km in the time trial. During the time trials, power output, mean skin temperature, rectal temperature, heart rate and rating of perceived exertion were assessed. The radiant heat exposure resulted in higher mean skin temperature during the time trial for short-heat (35.0 ± 0.6°C) and long-heat (35.3 ± 0.5°C) than for control (32.5 ± 1.0°C; P < 0.001), whereas rectal temperature was similar (P = 0.55). The mean power output was less for short-heat (273 ± 8 W; P = 0.001) and long-heat (271 ± 9 W; P = 0.02) than for control (287 ± 7 W), but pacing patterns did not differ (P = 0.55). Heart rate was greatest in control (177 ± 9 beats · min^?1; P < 0.001), whereas the rating of perceived exertion remained similar. We concluded that a radiant heat exposure and associated higher skin temperature reduced overall performance, but did not modify pacing pattern during a 15-km cycling time trial, regardless of the duration of the exposure.     

Health sciences libraries in Germany: new directions

This feature is part of a series about medical library services in various countries. It gives an overview of the state of and selected current developments of medical library services to support research, education and clinical practice in Germany. Findings from an online survey and issues of access to health information are discussed in relation to the German health care system.J.M.     

Does the accuracy matter? Accurate concept map feedback helps students improve the cohesion of their explanations

Students are often challenged by the demand of writing cohesive explanatory texts. Prior research has shown that providing students with concept map feedback that visualizes explanatory cohesion deficits helped students generate more cohesive explanations. We conducted an experiment to investigate whether the accuracy of the provided information within the concept map feedback affected students’ improvements of cohesion. Accordingly, we varied the represented accuracy of information within such concept maps: Students either received accurate concept map feedback that depicted the real relations between concepts, as well as the authentic cohesion gaps in their explanations, or students received inaccurate concept map feedback, which depicted randomly drawn relations and random cohesion gaps. Additionally, in a baseline condition, students did not receive any feedback. We found that the students in the accurate feedback condition generated more cohesive explanations than the students in the no-feedback condition, whereas the students in the inaccurate feedback condition lay in-between. Evidently, providing feedback in general can be regarded as beneficial to enhance students’ writing. However, the accuracy of the provided feedback further impacts the effectiveness of computer-generated concept maps.     

Commercialization of Technology News

While technology news has become a major news genre, the coverage of high-tech products has raised concerns regarding the commercialization of journalism. Drawing on salience transfer and exemplification theory, this study explores how The New York Times and USA Today covered Apple products along quantity and quality dimensions. A content analysis documented a landslide in the amount of coverage on Apple products in both newspapers. Both iPhones and iPads were disproportionately over-covered in relation to their market share. Over one-third of the headlines about the iPhone covered the product favorably. The New York Times published more stories about these gadgets than USA Today did, while USA Today was twice as likely to portray iPhones in a positive light. These findings have raised questions about the commercialization of technology news and its impact on journalism.     

Deviating glucose results in an international dual-center study. A root cause investigation

During a dual-center study on obese and normal weight children and adolescents, focusing on glucose metabolism, we observed a marked difference in glucose results (N = 16,840) between the two sites, Salzburg, Austria and Uppsala, Sweden (P < 0.001). After excluding differences in patient characteristics between the two populations as cause of this finding, we investigated other preanalytic influences. Finally, only the tubes used for blood collection at the two sites were left to evaluate. While the Vacuette FC-Mix tube (Greiner Bio-One, Kremsmünster, Austria) was used in Uppsala, in Salzburg blood collections were performed with a lithium heparin tube (LH-Monovette, Sarstedt, Germany). To prove our hypothesis, we collected two blood samples in either of these tubes from 51 children (Salzburg N = 27, Uppsala N = 24) and compared the measured glucose results. Indeed, we found the suspected bias and calculated a correction formula, which significantly diminished the differences of glucose results between the two sites (P = 0.023). Our finding is in line with those of other studies and although this issue should be widely known, we feel that it is widely neglected, especially when comparing glucose concentrations across Europe, using large databases without any information on preanalytic sample handling.     

Michaud,Montrond, Mazloum and the First History of the Crusades in Arabic

This short notice provides a novel and preliminary analysis of the source for the first Arabic history of the crusades, and contributes to the understanding of the penetration of the crusades as a distinct phenomenon into the Islamic world. The Arabic history, Min Ta?rīkh al-?urūb al-muqaddasa fī l-mashriq al-mad?ūwa ?arb al-?alīb was published in Jerusalem in 1865 under the authorship of the (late) Melkite patriarch, Maximos III Mazloum (d. 1855). The book was a modified translation of the French Les Guerres saintes d’Outre-Mer, ou tableau des croisades, retracé d’après les chroniques contemporaines, published in 1840 by Maxime de Montrond, who was heavily inspired by Michaud's Histoire des croisades. Though created in a Christian Francophile milieu, it seems clear that the Arabic translation was intended not only for a Christian audience, but also for a Muslim readership, as evidenced by examples, provided here, of the modifications of the French original.     

The origins of research into the origins of life

Most scientists at the end of the 19th and the beginning of the 20th century chose to ignore the question of the origin of life on Earth, regarding it as too mysterious and complex to handle. Yet, in the early 1950s an experimental field devoted to the study of the problem made its first steps. The pioneering theories of several scientists in the first decades of the 20th century played a major role in this transformation, notably those of the Russian biochemist Alexander I. Oparin and the British geneticist and biochemist J.B.S. Haldane. The ideas of the lesser-known American psycho-physiologist Leonard Troland also made a significant contribution to subsequent developments in origin-of-life research. Therefore, it is well worth taking a look at the professional, philosophical and ideological commitments that shaped the approaches of the three scientists to origin-of-life research.     

Sport activities differentiating match-play improvement in elite youth footballers – a 2-year longitudinal study

This study examined contributions of different types of sport activities to the development of elite youth soccer performance. Match-play performance of 44 German male players was assessed by expert coaches twice, 24 months apart (age 11.1–13.1 years), based on videotaped 5v5 matches. Player pairs were matched by identical age and initial performance at t₁. Each player was assigned to a group of either “Strong” or “Weak Responders” based on a higher or lower subsequent performance improvement at t₂ within each pair (mean Δperformance 29% vs. 7%). A questionnaire recorded current and earlier amounts of organised practice/training and non-organised sporting play, in soccer and other sports, respectively. Group comparison revealed that “Strong Responders” accumulated more non-organised soccer play and organised practice/training in other sports, but not more organised soccer practice/training. Subsequent multivariate analyses (multiple linear regression analyses (MLR)) highlighted that higher resultant match-play performance at t₂ was accounted for R²_adj = 0.65 by performance at t₁, together with more non-organised soccer play and organised engagement in other sports, respectively, and greater current, but less earlier volume of organised soccer. The findings suggest that variable early sporting experience facilitates subsequent soccer performance development in German elite youth footballers.