246 research outputs found

    Building a Bird: Musculoskeletal Modeling and Simulation of Wing-Assisted Incline Running during Avian Ontogeny

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    Flapping flight is the most power-demanding mode of locomotion, associated with a suite of anatomical specializations in extant adult birds. In contrast, many developing birds use their forelimbs to negotiate environments long before acquiring “flight adaptations,” recruiting their developing wings to continuously enhance leg performance and, in some cases, fly. How does anatomical development influence these locomotor behaviors? Isolating morphological contributions to wing performance is extremely challenging using purely empirical approaches. However, musculoskeletal modeling and simulation techniques can incorporate empirical data to explicitly examine the functional consequences of changing morphology by manipulating anatomical parameters individually and estimating their effects on locomotion. To assess how ontogenetic changes in anatomy affect locomotor capacity, we combined existing empirical data on muscle morphology, skeletal kinematics, and aerodynamic force production with advanced biomechanical modeling and simulation techniques to analyze the ontogeny of pectoral limb function in a precocial ground bird (Alectoris chukar). Simulations of wing-assisted incline running (WAIR) using these newly developed musculoskeletal models collectively suggest that immature birds have excess muscle capacity and are limited more by feather morphology, possibly because feathers grow more quickly and have a different style of growth than bones and muscles. These results provide critical information about the ontogeny and evolution of avian locomotion by (i) establishing how muscular and aerodynamic forces interface with the skeletal system to generate movement in morphing juvenile birds, and (ii) providing a benchmark to inform biomechanical modeling and simulation of other locomotor behaviors, both across extant species and among extinct theropod dinosaurs

    Partnership Evaluation Practices in Public-Nonprofit Community Sport Relationships: Understanding Resource Dependency

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    Interorganizational relationships (IORs) can offer community sport organizations (CSOs) a comprehensive and coordinated approach to address the complex issues in their environment (Misener & Doherty, 2014). IORs offer each partner access to specialized knowledge, information, and material resources (e.g. human, financial, infrastructure) that otherwise may be unattainable on their own (Huxham & Vangen, 2000). One type of partnership that may offer significant benefit to CSOs is public-sector partners such as municipal recreation departments who work closely with CSOs to coordinate facility use and offer support for sport delivery in their communities (Thibault, Frisby, Kikulis, 1999). However, the resource exchange and evaluation of IORs between CSOs and municipal partners has not been well understood (Jones, Edwards, Bocarro, Bunds, & Smith 2018). The study draws on resource dependency theory (Pfeffer & Salancik, 1978) as a lens for understanding how organizations can navigate power and resource flow in order to reduce environmental uncertainty and dependence (Hillman, Withers, & Collins, 2009). For CSOs, access to specific resources, and particularly infrastructure/facilities, is crucial to achieving their mandate. However, cross-sector partnerships may not achieve their potential because of imbalanced resources, misalignment of values, and different accountability structures and missions (Misener & Misener, 2017). Therefore, it is necessary to gain a greater understanding of the nature of resource exchange and potential dependency in CSO-public partnership. Partnership evaluation is often overlooked due to the absence of objective metrics, lack of evaluation skills, and inadequate time devoted to assessment (Babiak & Willem, 2016). Key components of evaluation include scoping, planning, managing, resourcing, and sustaining/terminating partnerships. In light of possible resource dependencies that shape the nature of public-CSO relations, it is essential to understand how resources influence evaluation practices in these partnerships (cf. Provan & Milward, 1998; Babiak, 2009). The purpose of this qualitative study is two-fold to (1) understand the nature of resource exchange and potential dependency in CSO-public partnerships, and (2) explore how resources influence partnership evaluation practices in CSO-public partnerships. Semi-structured interviews were conducted with the Manager/Coordinator/Director of Community Sport Relations (or similar position) within the Department of Recreation Services in five mid-size municipalities in Ontario. These individuals are responsible for managing facility distribution, providing support, collaborating on events, and managing communication with CSOs. Interviews were then conducted with 19 CSO Presidents (or their representative) from these communities who represent different sports and sizes of CSOs. The sample population provided a range of rural (2) and urban (3) municipalities as well as ten different sports (i.e. adult or youth) with varying resource capacities. Gaining the perspective of different sector partners enabled a more holistic understanding of partnership practices and evaluation strategies (Babiak, 2009). Interviews were transcribed verbatim and analyzed using inductive and deductive methods (Miles, Huberman, & Saldana, 2013). Analysis of the data revealed that the approach to the provision of resources and benefits exchanged between CSOs and the public sector represent more of a cumulative or “package” approach to resource exchange which expands our understanding beyond a "this for that" conceptualization of resource exchange that is more typical in the literature and offers a holistic understanding of the nature of resource exchange. In addition, five core themes; equity in decision making, fostering common vision, offering mutual support, increasing coordination and efficiency, and reducing uncertainty and promoting organizational stability emerged as effective ways to help public and CSO partners navigate resource uncertainty, dependency, and power influence in their environment. Finally, public and CSO partners mutual dependence for resources to achieve a similar objective of community sport development strongly influenced evaluation practices. Since both partners are unable to produce the quality and quantity of resources on their own, their dependence on each other remains high. Indeed, the total “package” approach of resources being exchanged also increased partners value and dependence in the relationship. Typically, even when a resource was considered low, other resource desires are still being supported and fulfilled, therefore decreasing partners needs to evaluate. Considerably, the lack of formal evaluation activities within this partnership can be attributed to partners vested interest in community sport development and their high interdependence on one another for resources. The present study contributes to the body of knowledge and practice of sport-based IORs at the community level. In addition, this research extends scholarly literature on public-CSO partnerships within a Canadian context. Finally, the study offers new understanding into resource exchange and dependency in public-CSO partnerships, while also offering insight into the influence of resource dependence on evaluation practices in this IOR relationship

    Microdiscectomy compared with transforaminal epidural steroid injection for persistent radicular pain caused by prolapsed intervertebral disc: the NERVES RCT

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    Background Sciatica is a common condition reported to affect > 3% of the UK population at any time and is most often caused by a prolapsed intervertebral disc. Currently, there is no uniformly adopted treatment strategy. Invasive treatments, such as surgery (i.e. microdiscectomy) and transforaminal epidural steroid injection, are often reserved for failed conservative treatment. Objective To compare the clinical effectiveness and cost-effectiveness of microdiscectomy with transforaminal epidural steroid injection for the management of radicular pain secondary to lumbar prolapsed intervertebral disc for non-emergency presentation of sciatica of < 12 months’ duration. Interventions Patients were randomised to either (1) microdiscectomy or (2) transforaminal epidural steroid injection. Design A pragmatic, multicentre, randomised prospective trial comparing microdiscectomy with transforaminal epidural steroid injection for sciatica due to prolapsed intervertebral disc with < 1 year symptom duration. Setting NHS services providing secondary spinal surgical care within the UK. Participants A total of 163 participants (aged 16–65 years) were recruited from 11 UK NHS outpatient clinics. Main outcome measures The primary outcome was participant-completed Oswestry Disability Questionnaire score at 18 weeks post randomisation. Secondary outcomes were visual analogue scores for leg pain and back pain; modified Roland–Morris score (for sciatica), Core Outcome Measures Index score and participant satisfaction at 12-weekly intervals. Cost-effectiveness and quality of life were assessed using the EuroQol-5 Dimensions, five-level version; Hospital Episode Statistics data; medication usage; and self-reported cost data at 12-weekly intervals. Adverse event data were collected. The economic outcome was incremental cost per quality-adjusted life-year gained from the perspective of the NHS in England. Results Eighty-three participants were allocated to transforaminal epidural steroid injection and 80 participants were allocated to microdiscectomy, using an online randomisation system. At week 18, Oswestry Disability Questionnaire scores had decreased, relative to baseline, by 26.7 points in the microdiscectomy group and by 24.5 points in the transforaminal epidural steroid injection. The difference between the treatments was not statistically significant (estimated treatment effect –4.25 points, 95% confidence interval –11.09 to 2.59 points). Nor were there significant differences between treatments in any of the secondary outcomes: Oswestry Disability Questionnaire scores, visual analogue scores for leg pain and back pain, modified Roland–Morris score and Core Outcome Measures Index score up to 54 weeks. There were four (3.8%) serious adverse events in the microdiscectomy group, including one nerve palsy (foot drop), and none in the transforaminal epidural steroid injection group. Compared with transforaminal epidural steroid injection, microdiscectomy had an incremental cost-effectiveness ratio of £38,737 per quality-adjusted life-year gained and a probability of 0.17 of being cost-effective at a willingness to pay threshold of £20,000 per quality-adjusted life-year. Limitations Primary outcome data was invalid or incomplete for 24% of participants. Sensitivity analyses demonstrated robustness to assumptions made regarding missing data. Eighteen per cent of participants in the transforaminal epidural steroid injection group subsequently received microdiscectomy prior to their primary outcome assessment. Conclusions To the best of our knowledge, the NErve Root Block VErsus Surgery trial is the first trial to evaluate the comparative clinical effectiveness and cost-effectiveness of microdiscectomy and transforaminal epidural steroid injection. No statistically significant difference was found between the two treatments for the primary outcome. It is unlikely that microdiscectomy is cost-effective compared with transforaminal epidural steroid injection at a threshold of £20,000 per quality-adjusted life-year for sciatica secondary to prolapsed intervertebral disc

    Epitope-specific antibody responses differentiate COVID-19 outcomes and variants of concern

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    BACKGROUND. The role of humoral immunity in COVID-19 is not fully understood, owing, in large part, to the complexity of antibodies produced in response to the SARS-CoV-2 infection. There is a pressing need for serology tests to assess patient-specific antibody response and predict clinical outcome. METHODS. Using SARS-CoV-2 proteome and peptide microarrays, we screened 146 COVID-19 patients’ plasma samples to identify antigens and epitopes. This enabled us to develop a master epitope array and an epitope-specific agglutination assay to gauge antibody responses systematically and with high resolution. RESULTS. We identified linear epitopes from the spike (S) and nucleocapsid (N) proteins and showed that the epitopes enabled higher resolution antibody profiling than the S or N protein antigen. Specifically, we found that antibody responses to the S-811–825, S-881–895, and N-156–170 epitopes negatively or positively correlated with clinical severity or patient survival. Moreover, we found that the P681H and S235F mutations associated with the coronavirus variant of concern B.1.1.7 altered the specificity of the corresponding epitopes. CONCLUSION. Epitope-resolved antibody testing not only affords a high-resolution alternative to conventional immunoassays to delineate the complex humoral immunity to SARS-CoV-2 and differentiate between neutralizing and non-neutralizing antibodies, but it also may potentially be used to predict clinical outcome. The epitope peptides can be readily modified to detect antibodies against variants of concern in both the peptide array and latex agglutination formats. FUNDING. Ontario Research Fund (ORF) COVID-19 Rapid Research Fund, Toronto COVID-19 Action Fund, Western University, Lawson Health Research Institute, London Health Sciences Foundation, and Academic Medical Organization of Southwestern Ontario (AMOSO) Innovation Fund

    Large-scale interaction profiling of PDZ domains through proteomic peptide-phage display using human and viral phage peptidomes

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    The human proteome contains a plethora of short linear motifs (SLiMs) that serve as binding interfaces for modular protein domains. Such interactions are crucial for signaling and other cellular processes, but are difficult to detect because of their low to moderate affinities. Here we developed a dedicated approach, proteomic peptide-phage display (ProP-PD), to identify domain-SLiM interactions. Specifically, we generated phage libraries containing all human and viral C-terminal peptides using custom oligonucleotide microarrays. With these libraries we screened the nine PSD-95/ Dlg/ZO-1 (PDZ) domains of human Densin-180, Erbin, Scribble, and Disks large homolog 1 for peptide ligands. We identified several known and putative interactions potentially relevant to cellular signaling pathways and confirmed interactions between fulllength Scribble and the target proteins ÎČ-PIX, plakophilin-4, and guanylate cyclase soluble subunit a-2 using colocalization and coimmunoprecipitation experiments. The affinities of recombinant Scribble PDZ domains and the synthetic peptides representing the C termini of these proteins were in the 1- to 40-ÎŒM range. Furthermore, we identified several well-established host-virus protein- protein interactions, and confirmed that PDZ domains of Scribble interact with the C terminus of Tax-1 of human T-cell leukemia virus with micromolar affinity. Previously unknown putative viral protein ligands for the PDZ domains of Scribble and Erbin were also identified. Thus, we demonstrate that our ProP-PD libraries are useful tools for probing PDZ domain interactions. The method can be extended to interrogate all potential eukaryotic, bacterial, and viral SLiMs and we suggest it will be a highly valuable approach for studying cellular and pathogen-host protein-protein interactions

    A multi-stage genome-wide association study of bladder cancer identifies multiple susceptibility loci.

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    We conducted a multi-stage, genome-wide association study of bladder cancer with a primary scan of 591,637 SNPs in 3,532 affected individuals (cases) and 5,120 controls of European descent from five studies followed by a replication strategy, which included 8,382 cases and 48,275 controls from 16 studies. In a combined analysis, we identified three new regions associated with bladder cancer on chromosomes 22q13.1, 19q12 and 2q37.1: rs1014971, (P = 8 × 10⁻ÂčÂČ) maps to a non-genic region of chromosome 22q13.1, rs8102137 (P = 2 × 10⁻ÂčÂč) on 19q12 maps to CCNE1 and rs11892031 (P = 1 × 10⁻⁷) maps to the UGT1A cluster on 2q37.1. We confirmed four previously identified genome-wide associations on chromosomes 3q28, 4p16.3, 8q24.21 and 8q24.3, validated previous candidate associations for the GSTM1 deletion (P = 4 × 10⁻ÂčÂč) and a tag SNP for NAT2 acetylation status (P = 4 × 10⁻ÂčÂč), and found interactions with smoking in both regions. Our findings on common variants associated with bladder cancer risk should provide new insights into the mechanisms of carcinogenesis

    A multi-stage genome-wide association study of bladder cancer identifies multiple susceptibility loci.

    Get PDF
    We conducted a multi-stage, genome-wide association study of bladder cancer with a primary scan of 591,637 SNPs in 3,532 affected individuals (cases) and 5,120 controls of European descent from five studies followed by a replication strategy, which included 8,382 cases and 48,275 controls from 16 studies. In a combined analysis, we identified three new regions associated with bladder cancer on chromosomes 22q13.1, 19q12 and 2q37.1: rs1014971, (P = 8 × 10⁻ÂčÂČ) maps to a non-genic region of chromosome 22q13.1, rs8102137 (P = 2 × 10⁻ÂčÂč) on 19q12 maps to CCNE1 and rs11892031 (P = 1 × 10⁻⁷) maps to the UGT1A cluster on 2q37.1. We confirmed four previously identified genome-wide associations on chromosomes 3q28, 4p16.3, 8q24.21 and 8q24.3, validated previous candidate associations for the GSTM1 deletion (P = 4 × 10⁻ÂčÂč) and a tag SNP for NAT2 acetylation status (P = 4 × 10⁻ÂčÂč), and found interactions with smoking in both regions. Our findings on common variants associated with bladder cancer risk should provide new insights into the mechanisms of carcinogenesis

    The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment

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    The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since July 2014. This paper describes the second data release from this phase, and the fourteenth from SDSS overall (making this, Data Release Fourteen or DR14). This release makes public data taken by SDSS-IV in its first two years of operation (July 2014-2016). Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey (eBOSS); the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data driven machine learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS website (www.sdss.org) has been updated for this release, and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020, and will be followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14 happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov 2017 (this is the "post-print" and "post-proofs" version; minor corrections only from v1, and most of errors found in proofs corrected

    Structures of the cGMP-dependent protein kinase in malaria parasites reveal a unique structural relay mechanism for activation.

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    The cyclic guanosine-3',5'-monophosphate (cGMP)-dependent protein kinase (PKG) was identified >25 y ago; however, efforts to obtain a structure of the entire PKG enzyme or catalytic domain from any species have failed. In malaria parasites, cooperative activation of PKG triggers crucial developmental transitions throughout the complex life cycle. We have determined the cGMP-free crystallographic structures of PKG from Plasmodium falciparum and Plasmodium vivax, revealing how key structural components, including an N-terminal autoinhibitory segment (AIS), four predicted cyclic nucleotide-binding domains (CNBs), and a kinase domain (KD), are arranged when the enzyme is inactive. The four CNBs and the KD are in a pentagonal configuration, with the AIS docked in the substrate site of the KD in a swapped-domain dimeric arrangement. We show that although the protein is predominantly a monomer (the dimer is unlikely to be representative of the physiological form), the binding of the AIS is necessary to keep Plasmodium PKG inactive. A major feature is a helix serving the dual role of the N-terminal helix of the KD as well as the capping helix of the neighboring CNB. A network of connecting helices between neighboring CNBs contributes to maintaining the kinase in its inactive conformation. We propose a scheme in which cooperative binding of cGMP, beginning at the CNB closest to the KD, transmits conformational changes around the pentagonal molecule in a structural relay mechanism, enabling PKG to orchestrate rapid, highly regulated developmental switches in response to dynamic modulation of cGMP levels in the parasite
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