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The fast and forceful kicking strike of the secretary bird
The study of animal locomotion has uncovered principles that can be applied to bio-inspired robotics, prosthetics and rehabilitation medicine, while also providing insight into musculoskeletal form and function [1, 2, 3, 4]. In particular, study of extreme behaviors can reveal mechanical constraints and trade-offs that have influenced evolution of limb form and function [1, 2]. Secretary birds (Sagittarius serpentarius; Figure 1A) are large terrestrial birds of prey endemic to sub-Saharan Africa, which feed on snakes, lizards and small mammals [5]. They frequently kick and stamp on the prey’s head until it is killed or incapacitated, particularly when dispatching larger lizards and venomous snakes [5]. The consequences of a missed strike when hunting venomous snakes can be deadly [5], so the kicking strikes of secretary birds require fast yet accurate neural control. Delivery of fast, forceful and accurate foot strikes that are sufficient to stun and kill prey requires precision targeting, demanding a high level of coordination between the visual and neuromuscular systems
Aminophobanes:hydrolytic stability, tautomerism and application in Cr-catalysed ethene oligomerisation
The bicyclic aminophobanes have significantly different chemistry from their acyclic analogues Cy2PNHR′.</p
Practitioner Perspectives on the Barriers Associated with Youth to Senior Transition in Elite Youth Soccer Academy Players
There are concerns surrounding the lack of players making the transition from youth to professional status within English professional soccer. Stakeholders, such as coaches, have been largely overlooked by researchers often focussing on player experiences. We aimed to explore soccer practitioner perceptions of the debilitating factors associated with youth to senior progression. Practitioners were chosen as they inform the working practices and are the cultural architects of the environment in which players operate. Interviews were conducted with 18 (N = 18), male (n = 17) and female (n = 1) soccer practitioners. These included coaches (n = 6), academy managers (n = 8) and staff involved with education and welfare (n = 4). Data were thematically analysed where four themes were identified (cultural climate, working practices, occupational hazards and social challenges). The analysis provided a clear picture of the transition landscape faced by players seeking to make the youth-to-senior transition through the eyes of soccer practitioners. The findings present a novel viewpoint to facilitate reflection around their own practice when managing youth to senior transitions. Further research is needed to triangulate player experiences and operational aspects of facilitating transitions which could lead to the creation of best practice guidance
Assessing activity participation in the ACL injured population: a systematic review of activity rating scale measurement properties
Background: Participation is an important factor in assessing both the requirement for and outcome from anterior cruciate ligament reconstruction. Many patient-reported rating scales exist; however, measurement properties have not been well established.
Objective: To provide a systematic review to identify currently available activity rating scales for anterior cruciate ligament injured subjects and to evaluate current knowledge of their measurement properties.
Methods: Systematic searches of four databases (Medline, AMED, EMBASE, and CINAHL) without date or language restriction, using terms structured around the PICOS system were completed on 1st March 2011. Citation tracking, reference screening and contact with lead authors of key papers completed the search strategy. Studies using participation rating scales were identified to assess frequency of reporting and cited validation. Studies assessing one or more psychometric properties of the identified rating scales were subject to independent data extraction and critical appraisal by two independent authors using published tools.
Results: Thirty-one rating scales were identified from 241 outcome studies. Most scales were inadequately developed or validated prior to use. Only three scales (Tegner, CSAS, and Marx) had psychometric analysis in eight studies of mixed quality. Only the Tegner scale has adequate assessment of reliability, validity, and responsiveness. The use of type, intensity, and frequency variables in the identified scales is discussed.
Conclusions: The Tegner scale has been adequately validated; however, other rating scales require further validation. A comprehensive comparative analysis of clinical applicability and psychometric testing of existing scales, including clinically useful statistics, is required
Spinal position sense and trunk muscle activity during sitting and standing in non-specific chronic low back pain: classification analysis
Study Design. A cross-sectional study between subgroups of nonspecific chronic low back pain (NSCLBP) and asymptomatic controls. Objective. To investigate NSCLBP subgroup differences in spinal position sense and trunk muscle activity when repositioning thoracic and lumbar spine into neutral (midrange) spinal position during sitting and standing. Summary of Background Data. Patients with NSCLBP report aggravation of symptoms during sitting and standing. Impaired motor control in NSCLBP, associated with sitting and standing postures nearer the end range of spinal motion, may be a contributing factor. Rehabilitation improving neutral (midrange) spinal position control is advocated. Postural and motor control alterations vary in different NSCLBP subgroups, potentially requiring specific postural interventions. There is limited evidence on whether subgroup differences exist when performing neutral spine position tasks. Methods. Ninety patients with NSCLBP and 35 asymptomatic controls were recruited. Two blinded practitioners classified NSCLBP into subgroups of active extension pattern and flexion pattern. Participants were assisted into neutral spine position and asked to reproduce this position 4 times. Absolute, variable, and constant errors were calculated. Three-dimensional thoracic and lumbar kinematics quantified the repositioning accuracy and surface electromyography assessed back and abdominal muscles activity bilaterally. Results. Irrespective of subclassification, patients with NSCLBP produced significantly greater error magnitude and variability than the asymptomatic controls, but subgroup differences were detected in the error direction. Subgroup differences in the trunk muscle activity were not consistently identified. Although both subgroups produced significantly higher abdominal activity, subclassification revealed difference in superficial multifidus activity during standing, with flexion pattern producing significantly greater activity than the asymptomatic controls. Conclusion. Subgroups of NSCLBP had similar neutral spinal position deficits regarding error magnitude and variability, but subclassification revealed clear subgroup differences in the direction of the deficit. The trunk muscle activation was shown to be largely nondiscriminatory between subgroups, with the exception of superficial lumbar multifidus
Photonic Sorting of Aligned, Crystalline Carbon Nanotube Textiles
Floating catalyst chemical vapor deposition uniquely generates aligned carbon nanotube (CNT) textiles with individual CNT lengths magnitudes longer than competing processes, though hindered by impurities and intrinsic/extrinsic defects. We present a photonic-based post-process, particularly suited for these textiles, that selectively removes defective CNTs and other carbons not forming a threshold thermal pathway. In this method, a large diameter laser beam rasters across the surface of a partly aligned CNT textile in air, suspended from its ends. This results in brilliant, localized oxidation, where remaining material is an optically transparent film comprised of few-walled CNTs with profound and unique improvement in microstructure alignment and crystallinity. Raman spectroscopy shows substantial D peak suppression while preserving radial breathing modes. This increases the undoped, specific electrical conductivity at least an order of magnitude to beyond that of single-crystal graphite. Cryogenic conductivity measurements indicate intrinsic transport enhancement, opposed to simply removing nonconductive carbons/residual catalyst
Diphosphine Bioconjugates via Pt(0)-Catalyzed Hydrophosphination. A Versatile Chelator Platform for Technetium-99m and Rhenium-188 Radiolabeling of Biomolecules
The ability to append targeting biomolecules to chelators that efficiently coordinate to the diagnostic imaging radionuclide, 99mTc, and the therapeutic radionuclide, 188Re, can potentially enable receptor-targeted “theranostic” treatment of disease. Here we show that Pt(0)-catalyzed hydrophosphination reactions are well-suited to the derivatization of diphosphines with biomolecular moieties enabling the efficient synthesis of ligands of the type Ph2PCH2CH2P(CH2CH2-Glc)2 (L, where Glc = a glucose moiety) using the readily accessible Ph2PCH2CH2PH2 and acryl derivatives. It is shown that hydrophosphination of an acrylate derivative of a deprotected glucose can be carried out in aqueous media. Furthermore, the resulting glucose-chelator conjugates can be radiolabeled with either 99mTc(V) or 188Re(V) in high radiochemical yields (>95%), to furnish separable mixtures of cis- and trans-[M(O)2L2]+ (M = Tc, Re). Single photon emission computed tomography (SPECT) imaging and ex vivo biodistribution in healthy mice show that each isomer possesses favorable pharmacokinetic properties, with rapid clearance from blood circulation via a renal pathway. Both cis-[99mTc(O)2L2]+ and trans-[99mTc(O)2L2]+ exhibit high stability in serum. This new class of functionalized diphosphine chelators has the potential to provide access to receptor-targeted dual diagnostic/therapeutic pairs of radiopharmaceutical agents, for molecular 99mTc SPECT imaging and 188Re systemic radiotherapy.</p
Professional judgement and decision-making in the planning process of high-level adventure sports coaching practice
This investigation examined the planning and decision-making processes in adventure sports coaching. We utilised a thematic analysis approach to investigate the planning decision-making practices of a sample of high-level adventure sports coaches over a series of sessions. The investigation discovered that, in planning coaching activity, high-level adventure sports coaches draw on their epistemological values and domain-specific expertise, employ a synergy of classic and naturalistic decision-making processes, and continually audit the evolving coaching process. Based on these findings, implications for professional training, accreditation and development of adventure sports coaches are presented
Chloroplasts alter their morphology and accumulate at the pathogen interface during infection by Phytophthora infestans
Upon immune activation, chloroplasts switch off photosynthesis, produce antimicrobial compounds and associate with the nucleus through tubular extensions called stromules. Although it is well established that chloroplasts alter their position in response to light, little is known about the dynamics of chloroplast movement in response to pathogen attack. Here, we report that during infection with the Irish potato famine pathogen Phytophthora infestans, chloroplasts accumulate at the pathogen interface, associating with the specialized membrane that engulfs the pathogen haustorium. The chemical inhibition of actin polymerization reduces the accumulation of chloroplasts at pathogen haustoria, suggesting that this process is partially dependent on the actin cytoskeleton. However, chloroplast accumulation at haustoria does not necessarily rely on movement of the nucleus to this interface and is not affected by light conditions. Stromules are typically induced during infection, embracing haustoria and facilitating chloroplast interactions, to form dynamic organelle clusters. We found that infection-triggered stromule formation relies on BRASSINOSTEROID INSENSITIVE 1-ASSOCIATED KINASE 1 (BAK1)-mediated surface immune signaling, whereas chloroplast repositioning towards haustoria does not. Consistent with the defense-related induction of stromules, effector-mediated suppression of BAK1-mediated immune signaling reduced stromule formation during infection. On the other hand, immune recognition of the same effector stimulated stromules, presumably via a different pathway. These findings implicate chloroplasts in a polarized response upon pathogen attack and point to more complex functions of these organelles in plant–pathogen interactions.Fil: Savage, Zachary. Imperial College London; Reino UnidoFil: Duggan, Cian. Imperial College London; Reino UnidoFil: Toufexi, Alexia. Imperial College London; Reino UnidoFil: Pandey, Pooja. Imperial College London; Reino UnidoFil: Liang, Yuxi. Imperial College London; Reino UnidoFil: Segretin, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Yuen, Lok Him. Imperial College London; Reino UnidoFil: Gaboriau, David C. A.. Imperial College London; Reino UnidoFil: Leary, Alexandre Y.. Imperial College London; Reino UnidoFil: Tumtas, Yasin. Imperial College London; Reino UnidoFil: Khandare, Virendrasinh. Imperial College London; Reino UnidoFil: Ward, Andrew D.. Science and Technology Facilities Council; Reino UnidoFil: Botchway, Stanley W.. Science and Technology Facilities Council; Reino UnidoFil: Bateman, Benji C.. Science and Technology Facilities Council; Reino UnidoFil: Pan, Indranil. Alan Turing Institute; Reino Unido. Imperial College London; Reino UnidoFil: Schattat, Martin. Martin Luther Universitat Halle-Wittenberg; AlemaniaFil: Sparkes, Imogen. University of Bristol; Reino UnidoFil: Bozkurt, Osman Tolga. Imperial College London; Reino Unid
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