2,713 research outputs found

    Collaborative working in highways major maintenance projects

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    Over the last decade, there has been a growing emphasis on collaborations and partnering in the construction industry. This has been embraced in the UK highways maintenance sector, with partnering promoted by the client, leading to the formation of alliances and partnering frameworks. One of these is the construction management framework (CMF), the preferred method of procurement for major maintenance projects in the Highways Agency’s areas 9 and 10. This paper compares two road and structure renewals schemes carried out using the CMF. The first scheme was carried out in 2004 as one of the first of its type to be undertaken by the CMF; the second was a similar project carried out in 2006. Documentation of the two projects was reviewed to identify the benefits that were gained through working in collaboration, and if there was an improvement in performance as the framework became more established. The research considered key performance indicators, including cost and time predictability measures, respect for people surveys, innovations and lessons learned discussed at the time of the projects, and instructions for changes to works information. Data collected from both schemes show improvements in measurement and culture fostered by the CMF, and the advantages of the processes used are illustrated

    Linear modelling and Fourier spectroscopy of stress-relaxation in the cervical spine

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    Single joints of the cervical spine were subject to axial compressive loads and the load relaxation recorded for 15 minutes. Isochronal plots of stress against strain were plotted for each specimen and showed high linear correlation coefficients (>0.955). Accordingly, a linear model was chosen and fitted to data obtained from a fuller range (3 hours) of the complete relaxation curve. The relaxation times extracted from this model were approximately 10 minutes and 5 hours. Fourier transform of the relaxation curve allows the storage modulus and the loss modulus of the relaxation spectrum to be shown separately as functions of frequency. Fourier analysis shows that the cervical spine has a wide and smooth distribution of relaxation times. Examination of the higher frequency components of the relaxation in the region of 1 to 20 Hz show the loss modulus to be almost flat and tending towards zero. This work shows that while the disc is capable of dissipating a large proportion of the applied strain energy, it can only do this slowly, and the discs of the cervical spine are inefficient as `shock absorbers' of axial loads.published_or_final_versio

    Prelude to the Anthropocene: Two new North American Land Mammal Ages (NALMAs)

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    Human impacts have left and are leaving distinctive imprints in the geological record. Here we show that in North America, the human-caused changes evident in the mammalian fossil record since c. 14,000 years ago are as pronounced as earlier faunal changes that subdivide Cenozoic epochs into the North American Land Mammal Ages (NALMAs). Accordingly, we define two new North American Land Mammal Ages, the Santarosean and the Saintagustinean, which subdivide Holocene time and complete a biochronologic system that has proven extremely useful in dating terrestrial deposits and in revealing major features of faunal change through the past 66 million years. The new NALMAs highlight human-induced changes to the Earth system, and inform the debate on whether or not defining an Anthropocene epoch is justified, and if so, when it began

    The effect of the Cox-maze procedure for atrial fibrillation concomitant to mitral and tricuspid valve surgery

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    ObjectivesAtrial fibrillation (AF) is associated with less favorable outcomes in patients undergoing mitral valve and tricuspid valve surgery. Despite growing evidence on the potential benefits of surgical ablation for AF there is significant variability among surgeons in treatment of AF. The purpose of our study was to assess the effect of the Cox-maze procedure on operative and follow-up outcomes.MethodsIn our prospective study, patients who underwent isolated mitral valve or mitral valve+tricuspid valve surgery without history of AF (n = 506), with untreated AF (n = 75), or with Cox-maze procedure (n = 236) were included (N = 817). Sinus rhythm was captured according to Heart Rhythm Society guidelines. Patients who underwent the Cox-maze procedure were propensity score matched to patients without history of AF resulting in 208 pairs of patients.ResultsOperative outcomes were comparable after propensity score matching (Cox-maze procedure vs no AF) stroke/transient ischemic attack (0.5% vs 0.5%; P = 1.00), renal failure (2.9% vs 1.4%; P = .34), and operative mortality (1.4% vs 1.4%; P = 1.00). High return to sinus rhythm was documented at 6, 12, and 24 months (92%, 91%, and 86%, respectively) as well as sinus rhythm off antiarrhythmic drugs (79%, 84%, and 82%, respectively). Incidence of embolic stroke in patients who underwent Cox-maze procedure was 1.7% (4 out of 232 patients) and 5.1 cases per 1000 person-years. No difference in 4-year cumulative survival between propensity score-matched groups (91.9% vs 86.9%; log rank, 1.67; P = .20), but higher for patients who underwent Cox-maze procedure versus patients with untreated AF (hazard ratio, 2.47; P = .048). Higher additive European System for Cardiac Operative Risk Evaluation (odds ratio, 1.40; P < .001) and limited surgeon experience with Cox-maze procedure (odds ratio, 3.60; P < .001) were significant predictors for failure to perform Cox-maze procedure.ConclusionsIn our center, 76% of patients undergoing mitral valve or mitral valve+tricuspid valve surgery experiencing AF underwent concomitant Cox-maze procedure, which is considerably higher than the national average. No increased morbidity was associated with the Cox-maze procedure with the benefit of very low thromboembolic rate. These results suggest the need for performance-based education for AF surgical ablation to achieve optimal outcomes

    Role of circulating polyunsaturated fatty acids on cardiovascular diseases risk:analysis using Mendelian randomization and fatty acid genetic association data from over 114,000 UK Biobank participants

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    BACKGROUND: Despite early interest in the health effects of polyunsaturated fatty acids (PUFA), there is still substantial controversy and uncertainty on the evidence linking PUFA to cardiovascular diseases (CVDs). We investigated the effect of plasma concentration of omega-3 PUFA (i.e. docosahexaenoic acid (DHA) and total omega-3 PUFA) and omega-6 PUFA (i.e. linoleic acid and total omega-6 PUFA) on the risk of CVDs using Mendelian randomization. METHODS: We conducted the largest genome-wide association study (GWAS) of circulating PUFA to date including a sample of 114,999 individuals and incorporated these data in a two-sample Mendelian randomization framework to investigate the involvement of circulating PUFA on a wide range of CVDs in up to 1,153,768 individuals of European ancestry (i.e. coronary artery disease, ischemic stroke, haemorrhagic stroke, heart failure, atrial fibrillation, peripheral arterial disease, aortic aneurysm, venous thromboembolism and aortic valve stenosis). RESULTS: GWAS identified between 46 and 64 SNPs for the four PUFA traits, explaining 4.8–7.9% of circulating PUFA variance and with mean F statistics >100. Higher genetically predicted DHA (and total omega-3 fatty acids) concentration was related to higher risk of some cardiovascular endpoints; however, these findings did not pass our criteria for multiple testing correction and were attenuated when accounting for LDL-cholesterol through multivariable Mendelian randomization or excluding SNPs in the vicinity of the FADS locus. Estimates for the relation between higher genetically predicted linoleic acid (and total omega-6) concentration were inconsistent across different cardiovascular endpoints and Mendelian randomization methods. There was weak evidence of higher genetically predicted linoleic acid being related to lower risk of ischemic stroke and peripheral artery disease when accounting by LDL-cholesterol. CONCLUSIONS: We have conducted the largest GWAS of circulating PUFA to date and the most comprehensive Mendelian randomization analyses. Overall, our Mendelian randomization findings do not support a protective role of circulating PUFA concentration on the risk of CVDs. However, horizontal pleiotropy via lipoprotein-related traits could be a key source of bias in our analyses. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12916-022-02399-w

    Treatment of Intrusive Suicidal Imagery Using Eye Movements

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    Suicide and suicidal behavior are major public health concerns, and affect 3–9% of the population worldwide. Despite increased efforts for national suicide prevention strategies, there are still few effective interventions available for reducing suicide risk. In this article, we describe various theoretical approaches for suicide ideation and behavior, and propose to examine the possible effectiveness of a new and innovative preventive strategy. A model of suicidal intrusion (mental imagery related to suicide, also referred to as suicidal flash-forwards) is presented describing one of the assumed mechanisms in the etiology of suicide and the mechanism of therapeutic change. We provide a brief rationale for an Eye Movement Dual Task (EMDT) treatment for suicidal intrusions, describing techniques that can be used to target these suicidal mental images and thoughts to reduce overall behavior. Based on the available empirical evidence for the mechanisms of suicidal intrusions, this approach appears to be a promising new treatment to prevent suicidal behavior as it potentially targets one of the linking pins between suicidal ideation and suicidal actions

    A modern multicentennial record of radiocarbon variability from an exactly dated bivalve chronology at the Tree Nob site (Alaska coastal current)

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    This is the final version. Available from Cambridge University Press via the DOI in this record. Quantifying the marine radiocarbon reservoir effect, offsets (ΔR), and ΔR variability over time is critical to improving dating estimates of marine samples while also providing a proxy of water mass dynamics. In the northeastern Pacific, where no high-resolution time series of ΔR has yet been established, we sampled radiocarbon (14C) from exactly dated growth increments in a multicentennial chronology of the long-lived bivalve, Pacific geoduck (Paneopea generosa) at the Tree Nob site, coastal British Columbia, Canada. Samples were taken at approximately decadal time intervals from 1725 CE to 1920 CE and indicate average ΔR values of 256 ± 22 years (1σ) consistent with existing discrete estimates. Temporal variability in ΔR is small relative to analogous Atlantic records except for an unusually old-water event, 1802–1812. The correlation between ΔR and sea surface temperature (SST) reconstructed from geoduck increment width is weakly significant (r2 = .29, p = .03), indicating warm water is generally old, when the 1802–1812 interval is excluded. This interval contains the oldest (–2.1σ) anomaly, and that is coincident with the coldest (–2.7σ) anomalies of the temperature reconstruction. An additional 32 14C values spanning 1952–1980 were detrended using a northeastern Pacific bomb pulse curve. Significant positive correlations were identified between the detrended 14C data and annual El Niño Southern Oscillation (ENSO) and summer SST such that cooler conditions are associated with older water. Thus, 14C is generally relatively stable with weak, potentially inconsistent associations to climate variables, but capable of infrequent excursions as illustrated by the unusually cold, old-water 1802–1812 interval.National Science FoundationNational Science Foundatio

    The rationale for heart team decision-making for patients with stable, complex coronary artery disease

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    Stable complex coronary artery disease can be treated with coronary artery bypass grafting (CABG), percutaneous coronary intervention (PCI), or medical therapy. Multidisciplinary decision-making has gained more emphasis over the recent years to select the most optimal treatment strategy for individual patients with stable complex coronary artery disease. However, the so-called 'Heart Team' concept has not been widely implemented. Yet, decision-making has shown to remain suboptimal; there is large variability in PCI-to-CABG ratios, which may predominantly be the consequence of physician-related factors that have raised concerns regarding overuse, underuse, and inappropriate selection of revascularization. In this review, we summarize these and additional data to support the statement that a multidisciplinary Heart Team consisting of at least a clinical/non-invasive cardiologist, interventional cardiologist, and cardiac surgeon, can together better analyse and interpret the available diagnostic evidence, put into context the clinical condition of the patient as well as consider individual preference and local expertise, and through shared decision-making with the patient can arrive at a most optimal joint treatment strategy recommendation for patients with stable co

    The inter-observer agreement of examining pre-school children with acute cough: a nested study

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    BACKGROUND: The presence of clinical signs have implications for diagnosis, prognosis and treatment. Therefore, the aim of this study was to examine the inter-observer agreement of clinical signs in pre-school children presenting to primary care. METHODS: A nested study comparing two clinical assessments within a prospective cohort of 256 pre-school children with acute cough recruited from eight general practices in Leicestershire, UK. We examined agreement (using kappa statistics) between unstandardised and standardised clinical assessments of tachypnoea, chest signs and fever. RESULTS: Kappa values were poor or fair for all clinical signs (range 0.12 to 0.39) with chest signs the most reliable. CONCLUSIONS: Primary care clinicians should be aware that clinical signs may be unreliable when making diagnosis, prognosis and treatment decisions in pre-school children with cough. Future research should aim to further our understanding of how best to identify abnormal clinical signs
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