17 research outputs found

    The western painted turtle genome, a model for the evolution of extreme physiological adaptations in a slowly evolving lineage

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    Background: We describe the genome of the western painted turtle, Chrysemys picta bellii, one of the most widespread, abundant, and well-studied turtles. We place the genome into a comparative evolutionary context, and focus on genomic features associated with tooth loss, immune function, longevity, sex differentiation and determination, and the species' physiological capacities to withstand extreme anoxia and tissue freezing.Results: Our phylogenetic analyses confirm that turtles are the sister group to living archosaurs, and demonstrate an extraordinarily slow rate of sequence evolution in the painted turtle. The ability of the painted turtle to withstand complete anoxia and partial freezing appears to be associated with common vertebrate gene networks, and we identify candidate genes for future functional analyses. Tooth loss shares a common pattern of pseudogenization and degradation of tooth-specific genes with birds, although the rate of accumulation of mutations is much slower in the painted turtle. Genes associated with sex differentiation generally reflect phylogeny rather than convergence in sex determination functionality. Among gene families that demonstrate exceptional expansions or show signatures of strong natural selection, immune function and musculoskeletal patterning genes are consistently over-represented.Conclusions: Our comparative genomic analyses indicate that common vertebrate regulatory networks, some of which have analogs in human diseases, are often involved in the western painted turtle's extraordinary physiological capacities. As these regulatory pathways are analyzed at the functional level, the painted turtle may offer important insights into the management of a number of human health disorders

    Kinematic responses to plyometric exercises conducted on compliant and noncompliant surfaces

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    Jumping is an important performance component of many sporting activities. A number of training modalities have been used to enhance jumping performance including plyometrics. The positive effects of plyometric training on jumping performance are a function of the stretch-shortening cycle phenomenon. However, there has been little research on the effects of the surface on jumping performance. This study examined the effects of performing 2 different plyometric exercises, depth jump (DJ) and counter movement jump (CMJ), on noncompliant (ground) and compliant (mini-trampoline) surfaces. Male participants (N = 20; age = 21.8 +/- 3.8 years; height = 184.6 +/- 7.6 cm; mass = 83.6 +/- 8.2 kg) randomly performed 10 CMJ and 10 DJ on compliant and noncompliant surfaces. Kinematic data were determined via 2-dimensional high-speed video. There were significant (p < 0.05) differences in DJ and CMJ joint and segment range of movement for ankle, knee, hip and trunk, indicating less crouch when the participants performed plyometric exercises on the compliant surface

    The effects of resisted sprint training on acceleration performance and kinematics in soccer, rugby union, and Australian football players

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    Acceleration is a significant feature of game-deciding situations in the various codes of football. However little is known about the acceleration characteristics of football players, the effects of acceleration training, or the effectiveness of different training modalities. This study examined the effects of resisted sprint (RS) training (weighted sled towing) on acceleration performance (0-15 m), leg power (countermovement jump [CMJ], 5-bound test [5BT], and 50-cm drop jump [50DJ]), gait (foot contact time, stride length, stride frequency, step length, and flight time), and joint (shoulder, elbow, hip, and knee) kinematics in men (N = 30) currently playing soccer, rugby union, or Australian football. Gait and kinematic measurements were derived from the first and second strides of an acceleration effort. Participants were randomly assigned to 1 of 3 treatment conditions: (a) 8-week sprint training of two 1-h sessions[middle dot]wk-1 plus RS training (RS group, n = 10), (b) 8-week nonresisted sprint training program of two 1-h sessions[middle dot]wk-1 (NRS group, n = 10), or (c) control (n = 10). The results indicated that an 8-week RS training program (a) significantly improves acceleration and leg power (CMJ and 5BT) performance but is no more effective than an 8-week NRS training program, (b) significantly improves reactive strength (50DJ), and (c) has minimal impact on gait and upper- and lower-body kinematics during acceleration performance compared to an 8-week NRS training program. These findings suggest that RS training will not adversely affect acceleration kinematics and gait. Although apparently no more effective than NRS training, this training modality provides an overload stimulus to acceleration mechanics and recruitment of the hip and knee extensors, resulting in greater application of horizontal power

    Quartz crystal microbalance study of volume changes and modulus shift in electrochemically switched polypyrrole

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    The performance of conducting polymers as actuators is determined by a complicated series of molecular processes that occur as a result of oxidation and reduction of the polymer. In particular, the amount of actuation strain generated for a given voltage stimulus is determined by the number and type of ions (and solvent) that enter and leave the polymer and changes in the mechanical properties (particularly elastic modulus) of the polymer. In this paper, we present the effects of cyclic voltammetry on the shear modulus and volume of polypyrrole in two different electrolytes: propylene carbonate and an ionic liquid. An electrochemical quartzcrystalmicrobalance has been used to study simultaneous volume and moduluschanges occurring during redox cycling of polypyrrole. The results demonstrate that the modulus generally increases due to oxidation of the polymer, although initial oxidation from the fully reduced state first produces a decrease in modulus followed by a larger increase. The modulusshift and volumechanges were smaller in the ionic liquid electrolyte, probably because of the absence of solvent. Comparison of the results obtained in the two electrolytes suggest that interchain interactions dominate in the determination of modulus, so that modulus is higher in the oxidised state even when the polymer is swollen with counterions and solvent

    Frequency and use of pain assessment tools implemented in randomized controlled trials in the adult burns population: A systematic review

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    Introduction: Pain continues to be an ongoing issue of concern in adult burn patients. Inadequate pain assessment hinders meaningful research, and prevents the optimal management of burn pain. The objective of this study was to examine the content of existing research in burn pain with the frequency and context of pain assessment tool use in randomized clinical trials in order to further inform their use for future researchers and clinicians. Methods: Electronic searches of MEDLINE, CINAHL, EMBASE and The Cochrane Library databases from 1966 onwards were used to identify English articles related to clinical trials utilising pain assessment in adult burns patients. Results: The systematic literature search identified 25 randomized clinical trials utilising pain assessment tools. Unidimensional pain assessment tools were most frequently used pain assessment tools, with multidimensional tools used less often, despite the multifaceted and complex nature of burn pain. Conclusion: The review highlights the lack of consistency of pain assessment tool use in randomized clinical trials with respect to managing burn pain. We recommend a broader but consistent use of multidimensional pain assessment tools for researchers undertaking clinical trials in this field. The review supports the need for an international expert consensus to identify the necessary critical outcomes and domains for clinicians and researchers undertaking further research into burn pain

    The value of secondary pathology review

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    6 Background: Improving the value of cancer care is a major focus for the Alliance of Dedicated Cancer Centers (ADCC). Looking to align with the Institute of Medicine’s (IOM) initiative to “Develop and deploy approaches to identify, learn from, and reduce diagnostic errors and near misses in clinical practice,” the ADCC implemented a study to examine the clinical impact of expert secondary pathology review. The goal of this project was to: 1) demonstrate the value of secondary review of outside pathological specimens by ADCC subspecialty pathologists in identifying significant errors that can potentially impact treatment; and 2) create an opportunity to improve patient cancer care. Methods: All consult slides from patients referred to each ADCC center were reviewed by designated pathologists. Patient-level data for original and revised diagnoses were collected for two months in 2014. Discrepancies were classified as: 1) major - diagnosis changes treatment or surveillance; or, 2) minor - diagnosis does not change affect treatment or surveillance. To verify these assessments, disease-specific, multi-center teams of clinical experts reviewed each discrepant case and provided treatment recommendations for the original and revised diagnoses. Results: A total of 13,109 cases were collected across all ADCC centers and the discrepancy rate was 11% (1,488/1309); 3% (359/13,109) were major and 9% (1,129/13,109) were minor. The most common discrepancy was reclassification of the neoplasm cell type. The highest discrepancy rate was shown in the neuro-oncology and head and neck cases, with a 7% and 4% major discrepancy rate respectively. Conclusions: We identified an overall discrepancy rate of 11%, with 3% of cases leading to a change in treatment or surveillance. This demonstrates the importance of expert pathology review and that secondary pathology review can significantly improve clinical outcomes through precise and accurate pathological diagnoses. As indicated in the recent IOM report, this project further demonstrates that “diagnostic errors may cause harm to patients by preventing or delaying appropriate treatment, providing unnecessary or harmful treatment, or resulting in psychological or financial repercussions.
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