The External Validity of a Novel Contract-Relax Stretching Technique on Knee Flexor Range of Motion

INTRODUCTION: Compromised joint range of motion (ROM) can negatively affect the capacity to perform activities of daily living in clinical populations. Recently, similar improvements in dorsiflexion ROM were reported following dynamometry-based contract-relax (CR) stretching and modified CR stretching technique (stretch-return-contract [SRC]) where the contraction phase was performed "off stretch." As neither the impact of SRC on other muscle groups nor the ecological validity of SRC performed in an applied environment has been tested, the acute effects of both techniques in dynamometry- (CR dyna and SRC dyna ) and field-based (CR field and SRC field ) environments were compared with the hamstring muscle group. METHODS: Seventeen participants performed each of the four stretching conditions on separate days in a randomized order. Before and after the stretches, knee extension ROM and passive knee flexor moment were recorded on an isokinetic dynamometer. RESULTS: Significant (P .05) in any measure was found between conditions. CONCLUSIONS: These data confirm the acute efficacy of the SRC technique in the hamstring muscle group and demonstrate its ecological validity in an applied environment in healthy participants. As the field-based SRC technique was performed without partner assistance, when compared with classical PNF it represents an equally effective and practical stretching paradigm to support athletic and clinical exercise prescription

Cubic γ-phase U–Mo alloys synthesized by splat-cooling

U–Mo alloys are the most promising materials fulfilling the requirements of using low enriched uranium (LEU) fuel in research reactors. From a fundamental standpoint, it is of interest to determine the basic thermodynamic properties of the cubic γ-phase U–Mo alloys. We focus our attention on the use of Mo doping together with ultrafast cooling (with high cooling rates ≥106 K s−1), which helps to maintain the cubic γ-phase in U–Mo system to low temperatures and on determination of the low-temperature properties of these γ-U alloys. Using a splat cooling method it has been possible to maintain some fraction of the high-temperature γ-phase at room temperature in pure uranium. U-13 at.% Mo splat clearly exhibits the pure γ-phase structure. All the splats become superconducting with Tc in the range from 1.24 K (pure U splat) to 2.11 K (U-15 at.% Mo). The γ-phase in U–Mo alloys undergoes eutectoid decomposition to form equilibrium phases of orthorhombic α-uranium and tetragonal γ'-phase upon annealing at 500 °C, while annealing at 800 °C has stabilized the initial γ phase. The α-U easily absorbs a large amount of hydrogen (UH3 hydride), while the cubic bcc phase does not absorb any detectable amount of hydrogen at pressures below 1 bar and at room temperature. At 80 bar, the U-15 at.% Mo splat becomes powder consisting of elongated particles of 1–2 mm, revealing amorphous state

Protocol: the effects of flipped classrooms to improve learning outcomes in undergraduate health professional education: a systematic review

[Extract] The teaching and learning activities of any undergraduate curriculum will have a specific set of learning outcomes that should be successfully achieved by the students. The balance between the workload of a student and the available time to achieve the learning outcomes plays a major role in achieving these learning outcomes, as well as a good student satisfaction score and excellent final grades for that particular module (Whillier & Lystad, 2013). In a traditional educational experience, a teacher stands in front of the classroom, delivers a lecture to a group of students, who sit in rows, quietly listening to the lecture and taking notes. At the end of the lecture, students are given homework or an assignment to be completed outside of the classroom environment. This characterises the principle of “sage‐on‐the stage”, and is synonymous with the present day term of teacher‐centered learning. This is also referred to as the transmittal model (King, 1993), which assumes that the students are passive note‐takers, receivers of the content or accumulators of factoids (Morrison, 2014). Usually, the teacher does not have time to interact with the students individually during the class (Hamdan, McKnight, McKnight & Arfstorm, 2013), thus neglecting those students who do not understand the lecture. The traditional didactic way of teaching is primarily unidirectional and consists of limited interactions between the source of knowledge (teacher) and the passive recipients (students)

Acute effects of lab- and field-based contract-relax (CR) and modified CR stretching on knee flexor muscle-tendon mechanics

Introduction: Similar mechanical and neurological changes have recently been reported at the ankle following traditional contract-relax (CR) stretching and a modified contract-relax (MCR) technique where the contraction phase was performed ‘off stretch’ (Kay et al., 2016). However, as these techniques were performed in a dynamometer, the efficacy of the modified technique in an athletic environment remains unknown. Therefore, the acute effects of both techniques were examined in lab- and field-based environments. Methods: Using a randomised, cross-over design, 17 recreationally active subjects performed the CRlab, CRfield, MCRlab and MCRfield hamstring stretches (4 x 10-s stretches + 5-s contractions) on separate days. Before and after the stretches, maximal isometric and passive knee flexor moment and knee extension range of motion (ROM) were recorded on an isokinetic dynamometer. Semitendinosus electromyographic (EMG) activity was recorded simultaneously, whilst ultrasound imaging was used to record biceps femoris tendon elongation. Results: Significant increases in knee extension ROM (4.6-5.2°; P 0.05) in maximal isometric strength, or volitional or reflexive EMG was observed in any condition. A significantly greater increase in elastic energy potential was observed following field- than lab-based stretches (P 0.05). Conclusion: The similar mechanical changes observed after CR and MCR stretching in lab- and field-based environments are indicative of common underlying mechanisms explaining the analogous ROM improvements. These data confirm both the efficacy of the MCR stretch technique to enhance knee flexor ROM and the ecological validity of performing this technique in an athletic environment. The implications for current practice are substantial as subjects completed the MCR technique without partner assistance, yet achieved similar acute increases in ROM as traditional CR stretching (i.e. the most effective stretching mode). Thus, the MCR stretching technique represents an equally effective yet more practical stretching paradigm. References Kay AD, Dods S, Blazevich AJ. (2016). Acute effects of contract-relax (CR) stretch versus a modified CR technique. Eur J Appl Physiol. doi: 10.1007/s00421-015-3320-8 Contact: [email protected]

Likert scales: how to (ab)use them?

No abstract available

Atomic-scale Studies of Uranium Oxidation and Corrosion by Water Vapour

Understanding the corrosion of uranium is important for its safe, long-term storage. Uranium metal corrodes rapidly in air, but the exact mechanism remains subject to debate. Atom Probe Tomography was used to investigate the surface microstructure of metallic depleted uranium specimens following polishing and exposure to moist air. A complex, corrugated metal-oxide interface was observed, with approximately 60 at.% oxygen content within the oxide. Interestingly, a very thin (~5 nm) interfacial layer of uranium hydride was observed at the oxide-metal interface. Exposure to deuterated water vapour produced an equivalent deuteride signal at the metal-oxide interface, confirming the hydride as originating via the water vapour oxidation mechanism. Hydroxide ions were detected uniformly throughout the oxide, yet showed reduced prominence at the metal interface. These results support a proposed mechanism for the oxidation of uranium in water vapour environments where the transport of hydroxyl species and the formation of hydride are key to understanding the observed behaviour

Geographical distribution of publications in the field of medical education

BACKGROUND: The geographical distribution of publications as an indicator of the research productivity of individual countries, regions or institutions has become a field of interest. We investigated the geographical distribution of contributions to the two leading journals in the field of medical education, Academic Medicine and Medical Education. METHODS: PubMed was used to search Medline. For both journals all journal articles in each year from 1995 to 2000 were included into the study. Then the affiliation was retrieved from the affiliation field of the MEDLINE format. If this was not possible, it was obtained from the paper version of the journal. RESULTS: Academic Medicine published contributions from 25 countries between 1995 and 2000. Authors from 50 countries contributed to Medical Education in the same period of time. Authors from the USA and Canada wrote ca. 95% off all articles in Academic Medicine, whereas authors from the UK, Australia, the USA, Canada and the Netherlands were responsible for ca. 74% of all articles in Medical Education in the investigated period of time. CONCLUSIONS: While many countries contributed to both journals, only a few of them were responsible for the majority of all articles

Can agricultural cultivation methods influence the healthfulness of crops for foods

The aim of the current study was to investigate if there are any health effects of long-term consumption of organically grown crops using a rat model. Crops were retrieved over two years from along-term field trial at three different locations in Denmark, using three different cultivation systems(OA, organic based on livestock manure; OB, organic based on green manure; and C, conventional with mineral fertilizers and pesticides)with two field replicates. The cultivation system had an impact on the nutritional quality, affecting γ-tocopherol, some amino acids, and fatty acid composition. Additionally, the nutritional quality was affected by harvest year and location. However, harvest year and location rather than cultivation system affected the measured health biomarkers. In conclusion, the differences in dietary treatments composed of ingredients from different cultivation systems did not lead to significant differences in the measured health biomarkers, except for a significant difference in plasma IgGl evels

Discourses and practices in teaching methods and assessment: Insights from an early career academic

© The Author(s) 2015. Translating the purposes of education into practice is particularly challenging for those who are new or have recently entered academia. By reflecting on my first years of teaching in higher education, I discuss two key aspects of my teaching practice: shifts in choice of teaching methods and a critique of different forms of assessment. Through the discussion, I argue that a teacher needs to be reflective on both these aspects and that such reflection needs to be carried out so that the student develops into a “self-directing,” “self-monitoring,” and “self-correcting” individual. At the end of the discussion, the relevance of a “project-based learning” approach starts to become significant in taking my pedagogical practice forward