1,080 research outputs found

    The effect of intervertebral cartilage on neutral posture and range of motion in the necks of sauropod dinosaurs

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    The necks of sauropod dinosaurs were a key factor in their evolution. The habitual posture and range of motion of these necks has been controversial, and computer-aided studies have argued for an obligatory sub-horizontal pose. However, such studies are compromised by their failure to take into account the important role of intervertebral cartilage. This cartilage takes very different forms in different animals. Mammals and crocodilians have intervertebral discs, while birds have synovial joints in their necks. The form and thickness of cartilage varies significantly even among closely related taxa. We cannot yet tell whether the neck joints of sauropods more closely resembled those of birds or mammals. Inspection of CT scans showed cartilage:bone ratios of 4.5% for Sauroposeidon and about 20% and 15% for two juvenile Apatosaurus individuals. In extant animals, this ratio varied from 2.59% for the rhea to 24% for a juvenile giraffe. It is not yet possible to disentangle ontogenetic and taxonomic signals, but mammal cartilage is generally three times as thick as that of birds. Our most detailed work, on a turkey, yielded a cartilage:bone ratio of 4.56%. Articular cartilage also added 11% to the length of the turkey's zygapophyseal facets. Simple image manipulation suggests that incorporating 4.56% of neck cartilage into an intervertebral joint of a turkey raises neutral posture by 15°. If this were also true of sauropods, the true neutral pose of the neck would be much higher than has been depicted. An additional 11% of zygapophyseal facet length translates to 11% more range of motion at each joint. More precise quantitative results must await detailed modelling. In summary, including cartilage in our models of sauropod necks shows that they were longer, more elevated and more flexible than previously recognised

    Structural investigations of CeIrIn5{_5} and CeCoIn5{_5} on macroscopic and atomic length scales

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    For any thorough investigation of complex physical properties, as encountered in strongly correlated electron systems, not only single crystals of highest quality but also a detailed knowledge of the structural properties of the material are pivotal prerequisites. Here, we combine physical and chemical investigations on the prototypical heavy fermion superconductors CeIrIn5{_5} and CeCoIn5{_5} on atomic and macroscopic length scale to gain insight into their precise structural properties. Our approach spans from enhanced resolution X-ray diffraction experiments to atomic resolution by means of Scanning Tunneling Microscopy (STM) and reveal a certain type of local features (coexistence of minority and majority structural patterns) in the tetragonal HoCoGa5_5-type structure of both compounds.Comment: 8 pages, 5 figures, submitted to JPSJ (SCES 2013

    Introduction to the themed issue - Corporate power : agency, communication, influence and social policy

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    This paper introduces this themed issue of Critical Social Policy on the question of corporate power. Corporate power is recognized as an important agent in social policy making and delivery. However, to date there has been comparatively little attention to the crucial role that lobbying and corporate 'spin' play in helping to shape policy making contexts. This special issue of Critical Social Policy is concerned to bring such issues to the mainstream of social policy analysis. It is argued here that the rise of spin and public relations is a key feature of neoliberalism in the past two decades. These have worked to reshape policy making, resulting in pronounced changes in the content and process of policy making and it is argued that these have tended to marginalize or undermine democratic processes

    Образное осмысление движения в русском языке (на материале глаголов движения в русских народных говорах)

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    На диалектном материале исследуется семантика глаголов, обозначающих поступательное, колебательное и вращательное движение, и выявляются параметры, по которым происходит создание метафорических образов данных типов движения

    Improved ventricular function during inhalation of PGI(2) aerosol partly relies on enhanced myocardial contractility

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    Inhaled prostacyclin (PGI(2)) aerosol induces selective pulmonary vasodilation. Further, it improves right ventricular ( RV) function, which may largely rely on pulmonary vasodilation, but also on enhanced myocardial contractility. We investigated the effects of the inhaled PGI(2) analogs epoprostenol (EPO) and iloprost (ILO) on RV function and myocardial contractility in 9 anesthetized pigs receiving aerosolized EPO (25 and 50 ng center dot kg(-1) center dot min(-1)) and, consecutively, ILO (60 ng center dot kg(-1) center dot min(-1)) for 20 min each. We measured pulmonary artery pressure ( PAP), RV ejection fraction (RVEF) and RV end-diastolic-volume (RV-EDV), and left ventricular end-systolic pressure-volume-relation (end-systolic elastance, E-es). EPO and ILO reduced PAP, increased RVEF and reduced RVEDV. E-es was enhanced during all doses tested, which reached statistical significance during EPO25ng and ILO, but not during EPO50ng. PGI(2) aerosol enhances myocardial contractility in healthy pigs, contributing to improve RV function. Copyright (C) 2005 S. Karger AG, Basel

    Serum heparan sulfate levels are elevated in endotoxemia

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    <p>Abstract</p> <p>Background</p> <p>Increased vascular permeability is a characteristic feature of sepsis which, in the past, has been ascribed exclusively to a malfunction of endothelial cells. However, recently it has become evident that the endothelial glycocalyx is of considerable importance concerning various aspects of vascular physiology, e.g. the vascular barrier and inflammation. Heparan sulfate, one of its essential components is characteristically traceable in blood, in case the endothelial glycocalyx is damaged or destroyed.</p> <p>Methods</p> <p>In 15 pigs we investigated whether the administration of endotoxin from gram-negative bacteria (Escherichia coli) results in increased serum levels of heparan sulfate, signalizing a shedding of the glycocalyx. In addition, markers of inflammation (white blood cell count, platelet count, tumour necrosis factor-α and interleukin-6) were evaluated over an observation period of 6 hours.</p> <p>Results</p> <p>Serum heparan sulfate concentrations significantly increased over time in the endotoxin group and were significantly elevated in comparison to the control group 6 hours after administration of endotoxin (p < 0.001). In the endotoxin group all markers of inflammation significantly changed during the time course.</p> <p>Conclusions</p> <p>The administration of bacterial endotoxin induced a significant rise in degradation products of the endothelial glycocalyx.</p

    ASCORE: an up-to-date cardiovascular risk score for hypertensive patients reflecting contemporary clinical practice developed using the (ASCOT-BPLA) trial data.

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    A number of risk scores already exist to predict cardiovascular (CV) events. However, scores developed with data collected some time ago might not accurately predict the CV risk of contemporary hypertensive patients that benefit from more modern treatments and management. Using data from the randomised clinical trial Anglo-Scandinavian Cardiac Outcomes Trial-BPLA, with 15 955 hypertensive patients without previous CV disease receiving contemporary preventive CV management, we developed a new risk score predicting the 5-year risk of a first CV event (CV death, myocardial infarction or stroke). Cox proportional hazard models were used to develop a risk equation from baseline predictors. The final risk model (ASCORE) included age, sex, smoking, diabetes, previous blood pressure (BP) treatment, systolic BP, total cholesterol, high-density lipoprotein-cholesterol, fasting glucose and creatinine baseline variables. A simplified model (ASCORE-S) excluding laboratory variables was also derived. Both models showed very good internal validity. User-friendly integer score tables are reported for both models. Applying the latest Framingham risk score to our data significantly overpredicted the observed 5-year risk of the composite CV outcome. We conclude that risk scores derived using older databases (such as Framingham) may overestimate the CV risk of patients receiving current BP treatments; therefore, 'updated' risk scores are needed for current patients
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