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Reduced left ventricular filling following blood volume extraction does not result in compensatory augmentation of cardiac mechanics
Get PDFAn acute non-invasive reduction in preload has been shown to augment cardiac mechanics to maintain stroke volume and cardiac output. Such interventions induce concomitant changes in heart rate, whereas blood volume extraction reduces preload without changes in heart rate. Therefore, the purpose of this study was to determine whether a preload reduction in isolation resulted in augmented stroke volume achieved via enhanced cardiac mechanics. Nine healthy volunteers (four female, age 29 ± 11 years) underwent echocardiography for the assessment of left ventricular (LV) volumes and mechanics in a supine position at baseline and end extraction after the controlled removal of 25% of total blood volume (1062 ± 342 ml). Arterial blood pressure was monitored continuously by a pressure transducer attached to an indwelling radial artery catheter. Heart rate and total peripheral resistance were unchanged from baseline to end extraction, but systolic blood pressure was reduced (from 148 to 127 mmHg). From baseline to end extraction there were significant reductions in left ventricular end-diastolic volume (from 89 to 71 ml) and stroke volume (from 56 to 37 ml); however, there was no change in LV twist, basal or apical rotation. In contrast, LV longitudinal strain (from −20 to −17%) and basal circumferential strain (from −22 to −19%) were significantly reduced from baseline to end extraction. In conclusion, a reduction in preload during blood volume extraction does not result in compensatory changes in stroke volume or cardiac mechanics. Our data suggest that LV strain is dependent on LV filling and consequent geometry, whereas LV twist could be mediated by heart rate
Language as Communication vs. Language as Art: JRR Tolkien and early 20th-century radical linguistic experimentation
Get PDFThis article situates Tolkien’s “A Secret Vice” (and its accompanying notes and papers) within the cultural and intellectual milieu of the early 20th century. It claims that at the heart of Tolkien’s exploration in this material is the question of language as communication vs. language as art. It argues that Tolkien’s language invention navigates the (perceived) binary between a utilitarian aim for language invention (contemporary International Auxiliary Languages) vs. an aesthetic linguistic pursuit (contemporary Modernist and other avant-garde linguistic experimentation), by choosing a third (middle) way. It examines Tolkien's linguistic invention alongside the work of Sapir, Jespersen, Joyce, Stein, and the Dada and zaum poets
Understanding the material dimensions of the uneven deployment of renewable energy in two Italian regions
Get PDFDrawing on empirical material from two Italian regions, we show how various material dimensions have affected the spatial distribution and deployment of renewable energy (RE), in particular solar and wind energy. The paper draws on an approach to the analysis of materiality originally developed in the extractive industries literature, including fossil fuels. The paper acknowledges that RE forms have significantly fewer material components compared with coal, oil and gas and the other extractive industries. Nevertheless, the deployment of RE, the process of turning renewable ‘natural resources’ into productive use as viable forms of energy through stages of energy conversion, storage, transmission and distribution has material aspects like those involved in the deployment of fossil fuels. This paper aims to show how understanding these aspects of renewable energy offers an opportunity to unpack and explain how particular RE paths come to be favoured or hampered, and yields useful insights into the spatial unevenness and variation of RE deployment at the regional level. Italy has introduced a system of renewable energy incentives and between 2010 and 2012 experienced impressive growth in the renewable energy sector. The paper shows how the significant spatial variation in renewable energy deployment in the regions of Apulia and Tuscany can be explained in terms of the influence that the material dimensions exercised in relation to renewable energy deployment processes. The paper suggests that understanding the material dimensions of renewable energy offers useful insights into how and why RE realises – and quite often fails to realise – its potential in specific forms, spaces and places
Timing of Muscle Activation Is Altered During Single-Leg Landing Tasks After Anterior Cruciate Ligament Reconstruction at the Time of Return to Sport
Get PDFOBJECTIVES:It is well known that alterations in landing mechanics persist for years after anterior cruciate ligament reconstruction (ACL-R). Nevertheless, existing literature is controversial in reporting successful or unsuccessful recovery of prelanding muscle activation timing after ACL-R. The study aimed at comparing myoelectric and kinematic patterns during landing tasks between ACL-R and healthy subjects. DESIGN:Cross-sectional study. SETTING:Institutional research laboratory. PATIENTS AND INTERVENTION:Fifteen male athletes after ACL-R using patellar tendon and 11 using hamstrings autograft at the time of return to sport were recruited. Fifteen healthy athletes served as control group. Participants performed 4 different single-leg landing tasks arriving onto a force plate. MAIN OUTCOME MEASURES:Electromyographic (EMG) activity of knee extensors and flexors, normalized vertical ground reaction force (vGRF), and knee angular displacement were recorded. RESULTS:In all the tasks, preimpact EMG duration was longer in ACL-R (112 ± 28 ms in the knee extensors; 200 ± 34 ms in the knee flexors) compared with healthy participants (74 ± 19 ms in the knee extensors; 153 ± 29 ms in the knee flexors; P < 0.05). Initial contact (IC) and maximum postimpact knee angle were lower in ACL-R (9 ± 7 degrees at IC; 39 ± 12 degrees at maximum flexion) compared with healthy participants (17 ± 9 degrees at IC; 52 ± 15 degrees at maximum flexion; P < 0.05). Normalized vGRF was higher in ACL-R compared with healthy participants (3.4 ± 0.5 and 2.7 ± 0.6; P < 0.05). CONCLUSIONS:At the time of return to sport, ACL-R subjects showed altered motor control strategies of single-leg landings. These alterations may lead to uncoordinated movement, hence increasing the risk of reinjury
Highlights of the 2nd International Symposium on Tribbles and Diseases: Tribbles tremble in therapeutics for immunity, metabolism, fundamental cell biology and cancer
Get PDFThe Tribbles (TRIB) family of pseudokinase proteins has been shown to play key roles in cell cycle, metabolic diseases, chronic inflammatory disease, and cancer development. A better understanding of the mechanisms of TRIB pseudokinases could provide new insights for disease development and help promote TRIB proteins as novel therapeutic targets for drug discovery. At the 2nd International Symposium on Tribbles and Diseases held on May 7‒9, 2018 in Beijing, China, a group of leading Tribbles scientists reported their findings and ongoing studies about the effects of the different TRIB proteins in the areas of immunity, metabolism, fundamental cell biology and cancer. Here, we summarize important and insightful overviews from 4 keynote lectures, 13 plenary lectures and 8 short talks that took place during this meeting. These findings may offer new insights for the understanding of the roles of TRIB pseudokinases in the development of various diseases
Strengthening School Governance in Wales: A Community of Enquiry Approach
Get PDFIn 2013 Welsh Government implemented legislation which specified mandatory training for school governors in Wales. The training coincides with sustained improvement in school governance according to reports of Her Majesty's Inspectorate of Education and Training in Wales (Estyn). This article sets the scene with a brief incursion into literature on governance of schools in England. The absence of recent empirical studies in a Welsh context means there is little beyond Estyn reports to evaluate the efficacy of the mandatory training. The authors of this article developed, delivered and evaluated a pilot training programme for governors, based on the UNESCO definition of governance. Findings indicate the need for enhancements to governor development which go beyond monitoring school performance. The authors have identified a need to improve critical thinking and strategic planning which would enable governors and headteachers to work collaboratively, taking account of the external policy context and the vision and values of the school
How Is Physical Literacy Defined? A Contemporary Update
Get PDFPhysical literacy continues to gain global momentum, yet the definition and underlying concept of physical literacy remain contested in both research and practice. This lack of clarity has the potential to undermine the operationalization of physical literacy. This paper considers the various definitions of physical literacy that are currently adopted internationally. Physical literacy experts identified seven leading groups that have established physical literacy initiatives. Although each group is unified in using the term physical literacy, there are contrasting definitions and interpretations of the concept. Common themes were identified, including the (a) influence of physical literacy philosophy, (b) core elements of physical literacy, (c) lifelong nature of physical literacy, and (d) the need to scientifically pursue a robust operationalization of the concept. We conclude by recommending that programs relating to physical literacy should provide a definition, a clear philosophical approach, and transparency with how their actions align with this approach
Genome Analysis, Metabolic Potential, and Predatory Capabilities of Herpetosiphon llansteffanense sp. nov.
Get PDFHerpetosiphon spp. are ubiquitous, chemoheterotrophic, filamentous gliding bacteria with the ability to prey on other microbes through a “wolf pack” mechanism. The genus currently comprises four known species (H. aurantiacus, H. geysericola, H. giganteus, and H. gulosus), which produce antimicrobial secondary metabolites such as siphonazole. As part of a study isolating myxobacterial wolf pack predators, we serendipitously isolated a novel environmental strain (CA052B) from the edge of a stream at Llansteffan, United Kingdom, which was identified as a member of the Herpetosiphon genus. A lawn culture method was utilized to analyze the predatory activity of CA052B against 10 prey organisms of clinical relevance. CA052B was found to prey on Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus, Enterococcus faecalis, Bacillus subtilis, and Candida albicans. Purified CA052B outer membrane vesicles also exhibited killing activity against the prey organisms when tested by flow cytometry. 16S rRNA sequencing of CA052B showed 98 to 99% identity with other Herpetosiphon species members. Comparing the genome of CA052B with the publicly available genomes of H. aurantiacus and H. geysericola revealed average nucleotide identities of only 84% and 91%, respectively, whereas the genome-to-genome distance calculation showed sequence identities of 28.2% and 46.6%, respectively. Biochemical characterization also revealed distinctions between CA052B and both H. gulosus and H. giganteus. Thus, strain CA052BT (= DSM 107618T = NBRC 113495T) is proposed to be the type strain of a novel species, Herpetosiphon llansteffanense sp. nov. The genome sequence of CA052B also revealed diverse secondary metabolite biosynthetic clusters, encouraging further exploration of its antibiotic production potential
Supporting adolescent athletes' dual careers: The role of an athlete's social support network
Get PDFObjectives
The objectives of this study were to, (a) understand the role of the social support network in facilitating adolescent athletes' dual careers in sport and education, and; (b) gain insights into the factors that may optimize the provision of such support.
Design
A two-stage qualitative study.
Method
In stage one, four different sport and education settings in the UK were examined: A tennis academy, a football academy, a national field hockey squad, and a high-performance swimming squad. Interviews were conducted with two athletes and associated significant others from each setting. In stage two, nine current or former international athletes from a variety of sports and countries recalled their experiences of managing a dual career. Analysis was conducted following the procedures outlined by Miles, Huberman, and Saldaña (2014).
Results
Overall, athletes in stage one and two perceived that to maintain their dual careers, they were heavily dependent upon the support of significant others. The role of the support network was to recognize the demands of a dual career, anticipate problems, value education, minimize barriers, and create autonomy-supportive environments. Key factors to optimize such support were focusing on the whole person, providing integrated support, and fostering a culture that promotes continuing education.
Conclusions
Results indicate that athletes require particular types of support within their home, at school, and in their sport context to be able to manage their dual career. However, a range of individual and group-level factors may influence the extent to which such support is available to athletes
A longitudinal study of muscle strength and function in patients with cancer cachexia
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Patients with cancer frequently experience an involuntary loss of weight (in particular loss of muscle mass), defined as cachexia, with profound implications for independence and quality of life. The rate at which such patients’ physical performance declines has not been well established. The aim of this study was to determine the change in muscle strength and function over 8 weeks in patients with already established cancer cachexia, to help inform the design and duration of physical activity interventions applicable to this patient group.
Methods
Patients with thoracic and gastrointestinal cancer, with unintentional weight loss of >5% in 6 months or BMI < 20 plus 2% weight loss were included. Physical and functional assessments (baseline, 4 weeks, 8 weeks) included: isometric quadriceps and hamstring strength, handgrip, standing balance, 10m walk time and timed up and go.
Results
Fifty patients (32 male), mean ±SD age 65 ±10 years and BMI 24.9 ±4.3kg/m2 were recruited. Thoracic cancer patients had lower muscle strength and function (p0.05). Baseline variables did not differentiate between completers and non-completers (p>0.05).
Conclusions
More than a third of patients with established cancer cachexia in our study were stable over 8 weeks, suggesting a subgroup who may benefit from targeted interventions of reasonable duration. Better understanding the physical performance parameters which characterize and differentiate these patients has important clinical implications for cancer multidisciplinary team practice