62 research outputs found
Computer simulation and design of a three degree-of-freedom shoulder module
An in-depth kinematic analysis of a three degree of freedom fully-parallel robotic shoulder module is presented. The major goal of the analysis is to determine appropriate link dimensions which will provide a maximized workspace along with desirable input to output velocity and torque amplification. First order kinematic influence coefficients which describe the output velocity properties in terms of actuator motions provide a means to determine suitable geometric dimensions for the device. Through the use of computer simulation, optimal or near optimal link dimensions based on predetermined design criteria are provided for two different structural designs of the mechanism. The first uses three rotational inputs to control the output motion. The second design involves the use of four inputs, actuating any three inputs for a given position of the output link. Alternative actuator placements are examined to determine the most effective approach to control the output motion
Genetic insight into sick sinus syndrome
Aims. The aim of this study was to use human genetics to investigate the pathogenesis of sick sinus syndrome (SSS) and the role of risk factors in its development.
Methods and results. We performed a genome-wide association study of 6469 SSS cases and 1 000 187 controls from deCODE genetics, the Copenhagen Hospital Biobank, UK Biobank, and the HUNT study. Variants at six loci associated with SSS, a reported missense variant in MYH6, known atrial fibrillation (AF)/electrocardiogram variants at PITX2, ZFHX3, TTN/CCDC141, and SCN10A and a low-frequency (MAF = 1.1–1.8%) missense variant, p.Gly62Cys in KRT8 encoding the intermediate filament protein keratin 8. A full genotypic model best described the p.Gly62Cys association (P = 1.6 × 10⁻²⁰), with an odds ratio (OR) of 1.44 for heterozygotes and a disproportionally large OR of 13.99 for homozygotes. All the SSS variants increased the risk of pacemaker implantation. Their association with AF varied and p.Gly62Cys was the only variant not associating with any other arrhythmia or cardiovascular disease. We tested 17 exposure phenotypes in polygenic score (PGS) and Mendelian randomization analyses. Only two associated with the risk of SSS in Mendelian randomization, AF, and lower heart rate, suggesting causality. Powerful PGS analyses provided convincing evidence against causal associations for body mass index, cholesterol, triglycerides, and type 2 diabetes (P > 0.05).
Conclusion. We report the associations of variants at six loci with SSS, including a missense variant in KRT8 that confers high risk in homozygotes and points to a mechanism specific to SSS development. Mendelian randomization supports a causal role for AF in the development of SSS
Signalling Demand for Foreign Investment: Postsocialist Countries in the Global Bilateral Investment Treaties Network
A unique dataset on bilateral investment treaties provides a novel source of evidence on the link between neoliberal globalisation and market transition. We argue that postsocialist countries of Europe and Eurasia, more than other developing regions in the world, signed such treaties to signal demand for foreign investment in the spirit of neoliberalism. We calculated the density of the whole BIT network since its inception in 1959 to 2009, and density and centrality of different regional blocks within it, and found strong support for our argument. Yet, even if bilateral investment treaties are designed to promote foreign direct investment, dynamic panel regression models show that signing them does not automatically translate into foreign direct investment inflows for postsocialist European and Eurasian countries in the 1990–2010 period
Is compartment pressure related to plasma colloid osmotic pressure, in patients during and after cardiac surgery?
To access publisher full text version of this article. Please click on the hyperlink in Additional Links fieldHaemodilution is always considerable during cardiopulmonary bypass (CPB). If this extra fluid sits in the muscle compartments then a corresponding rise in the compartment pressure (CP) is to be expected. The aim of this study was to measure pressure changes in a body compartment with new equipment, the MTC (Microtransducer). Changes in plasma colloid osmotic pressure (COP) were also measured during and after CPB to find a connection, if any, between CP and plasma COP. Ten elective consecutive CPB patients were studied. A 3-French (3-F) catheter-size electronic MTC was inserted in an anterior tibial compartment before CPB. The CP was monitored for 48 h. Plasma COP was also measured before, during and after CPB. CP increased significantly during and after CPB in all patients (p=0.01). COP decreased significantly in all patients (p=0.005), but no correlation was found between changes in COP and CP values in this study. Most of the patients reached their highest CP just after weaning off bypass. The CP remained elevated for 48 h, even though it then tended to decrease again. None of the patients reached the starting value within 48 h. COP decreased rapidly after going on bypass, but returned towards its starting value approximately 6 h after bypass. It is concluded that CP increases considerably during and after CPB and stays increased for at least 2 days after CPB. COP decreases during CPB, but reaches normal values 6 h after the CPB. No correlation was found between changes in CP and COP The MTC is a safe and easy way to measure intracompartment pressure
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Comparison of five ELISA assays for IgG antibody against coxsackievirus B1
Enterovirus type and group specificities of five different IgG ELISA methods were compared, using neutralization titration tests as an indicator of the presence or absence of antibodies to coxsackie B (CB) viruses. One of the ELISA assays was a "standard" IgG assay, where the solid phase was coated directly with the purified virus, followed by incubations with human serum, biotinylated anti-human-IgG, streptavidin-peroxidase, and the substrate/chromogen. In a modified standard assay, blocking of common epitopes was attempted by incubating the CB1 virus antigen on the solid phase with a rabbit antiserum to CB5 before the human serum was added. In another modification the serum dilution buffer contained heat-denatured heterologous enteroviruses in an attempt to consume human antibodies reacting with common epitopes. In one assay the purified CB1 virus was captured by purified horse anti-CB1 IgG on the solid phase, before incubation with human serum. In the last of the five assays the serum specimen was incubated with CB1 virus (in the liquid phase) before the virus or virus-antibody complex was captured with purified horse anti-CB1-IgG. Reactions against common antigens dominated in the first three assays. The antigen-capture assay appeared to be at least predominantly type specific. Our data indicate that the liquid-phase assay may be type specific, but more studies are needed. The method of virus purification was critical for the type specificity of the antigen-capture and liquid-phase assays
Immune response against equine gammaherpesvirus in Icelandic horses
To access publisher full text version of this article. Please click on the hyperlink in Additional Links fieldHorses are hosts to two types of gammaherpesviruses, equine herpes virus (EHV) 2 and 5. While EHV-2 is ubiquitous in adult horses, EHV-5 has been less frequently described. Due to strong serological cross-reactivity, EHV-2 and -5 cannot be discriminated in broad spectrum antibody tests and are thus commonly referred to as gamma-EHV. Total IgG and IgG subclass response against gamma-EHV were determined in serum from 41 healthy Icelandic horses, thereof 20 adults, 10 foals aged 10 months, and 11 foals aged 1-4 months. Additionally, in 10 of the adult horses, interferon (IFN)-gamma and interleukin (IL)-4 expression were measured by real-time PCR in white blood cells upon in vitro stimulation with EHV-2. With the exception of one orphan foal, all tested individuals were seropositive for gamma-EHV. All but one adult had high titer of EHV-specific IgG4/7 (IgGb) in combination with much lower titer of IgG1 (IgGa) and IgG3/5 (IgG(T)), indicating a stabilized response. IgG titer and subclasses in the foals showed considerably more variation, possibly dependant on maternal antibodies and/or recent infection. In all the 10 horses tested for cytokine expression, IFN-gamma production exceeds production of IL-4. These results indicate that equine gammaherpesvirus infection is characterized by an induction of IgG1, IgG4/7 and IgG3/5 with prevailing IgG4/7 and cytokine profile dominated by IFN-gamma. To our knowledge, this is the first report on the cytokine and IgG subclass response against gamma-EHV in horses
Inflammatory response following heart surgery and association with n-3 and n-6 long-chain polyunsaturated fatty acids in plasma and red blood cell membrane lipids.
To access publisher's full text version of this article click on the hyperlink at the bottom of the pageOpen heart surgery is associated with a systemic inflammatory response. The n-3 long-chain polyunsaturated fatty acids (LC-PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and the n-6 LC-PUFA arachidonic acid (AA) may contribute to modulation of the inflammatory response.We investigated whether the preoperative levels of EPA, DHA and AA in plasma phospholipids (PL) and red blood cell (RBC) membrane lipids in patients (n=168) undergoing open heart surgery were associated with changes in the plasma concentration of selected inflammatory mediators in the immediate postoperative period.The postoperative concentration of TNF-β was lower (P<0.05) and those of hs-CRP, IL-6, IL-8, IL-18 and IL-10 higher (P<0.05) than the respective preoperative concentrations. We observed that the preoperative levels of EPA and AA in plasma PL and RBC membrane lipids were associated with changes in the concentration of pro-inflammatory and anti-inflammatory mediators, suggesting a complex role in the postoperative inflammatory process.Icelandic Research Fund (RANNIS)/080411021
University of Iceland Research Fund
Landspitali-The National University Hospital of Iceland Research Fun
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