272 research outputs found

    Heterogeneity after harmonisation: a retrospective cohort study of bleeding and stroke risk after the introduction of direct oral anticoagulants in four Western European countries

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    Purpose: Database heterogeneity can impact effect estimates. Harmonisation provided by common protocols and common data models (CDMs) can increase the validity of pharmacoepidemiologic research. In a case study measuring the changes in the safety and effectiveness of stroke prevention therapy after the introduction of direct oral anticoagulants (DOACs), we performed an international comparison. Methods: Using data from Stockholm, Denmark, Scotland and Norway, harmonised with a common protocol and CDM, two calendar-based cohorts were created: 2012 and 2017. Patients with a diagnosis code of atrial fibrillation 5 years preceding the 1-year cohort window were included. DOAC, vitamin K antagonist and aspirin treatment were assessed in the 6 months prior to the start of each year while strokes and bleeds were assessed during the year. A Poisson regression generated incidence rate ratios (IRRs) to compare outcomes from 2017 to 2012 adjusted for changes in individual-level baseline characteristics. Results: In 280 359 patients in the 2012 cohort and 356 779 in the 2017 cohort, treatment with OACs increased on average from 45% to 65%, while treatment with aspirin decreased from 30% to 10%. In all countries except Scotland, there were decreases in the risk of stroke and no changes in bleeding risk, after adjustment for changes in baseline characteristics. In Scotland, major bleeding (IRR 1.09, 95% confidence interval [CI] [1.00; 1.18]) and intracranial haemorrhage (IRR 1.31, 95% CI [1.13; 1.52]) increased from 2012 to 2017. Conclusions: Stroke prevention therapy improved from 2012 to 2017 with a corresponding reduction in stroke risk without increasing the risk of bleeding in all countries, except Scotland. The heterogeneity that remains after methodological harmonisation can be informative of the underlying population and database

    Freely decaying weak turbulence for sea surface gravity waves

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    We study numerically the generation of power laws in the framework of weak turbulence theory for surface gravity waves in deep water. Starting from a random wave field, we let the system evolve numerically according to the nonlinear Euler equations for gravity waves in infinitely deep water. In agreement with the theory of Zakharov and Filonenko, we find the formation of a power spectrum characterized by a power law of the form of ∣k∣−2.5|{\bf k}|^{-2.5}.Comment: 4 pages, 3 figure

    From community to assemblage? : ICT provides a site for inclusion and exclusion in the global south

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    The role of information and communication technology (ICT) in development has been discussed from two distinctly different perspectives: some view it as a means for opening new alleys for the facilitation of development and democracy, while others assess it as counterproductive. Furthermore, it has been emphasised that people in cities and rural areas utilise ICT in different ways, as do people with wealth and education compared to poor people. In Africa, Kenya has declared itself an ICT hub. The state has emphasised ICT in promoting services, much less freedom of expression. This article discusses ICT and development via the filter of assemblage, a key concept developed by Deleuze and Guattari (2004/1980. A Thousand Plateaus: Capitalism and Schizophrenia. London: Continuum.). They emphasised fluidity as well as micro- and macro-level dichotomies. When communities based on sharing and consistent social order meet new technology, the change goes deeper than that of improved services. The basic difference might be the fact that a community is constructed on cultural ties developed over time, which strengthens immobility and stability, while an assemblage is characterised by mobility and fluidity. Thus, a system of values, hierarchies, and inherited traditions is challenged, mixed with ‘new’ problems brought about by individualised behaviour.Peer reviewe

    The Role of Wind Waves in Dynamics of the Air-Sea Interface

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    Wind waves are considered as an intermediate small-scale dynamic process at the air-sea interface,which modulates radically middle-scale dynamic processes of the boundary layers in water and air. It is shown that with the aim of a quantitative description of the impact said, one can use the numerical wind wave models which are added with the blocks of the dynamic atmosphere boundary layer (DABL) and the dynamic water upper layer (DWUL). A mathematical formalization for the problem of energy and momentum transfer from the wind to the upper ocean is given on the basis of the well known mathematical representations for mechanisms of a wind wave spectrum evolution. The problem is solved quantitatively by means of introducing special system parameters: the relative rate of the wave energy input, IRE, and the relative rate of the wave energy dissipation, DRE. For two simple wave-origin situations, the certain estimations for values of IRE and DRE are found, and the examples of calculating an impact of a wind sea on the characteristics of both the boundary layer of atmosphere and the water upper layer are given. The results obtained permit to state that the models of wind waves of the new (fifth) generation, which are added with the blocks of the DABL and the DWUL, could be an essential chain of the general model describing the ocean-atmosphere circulation.Comment: 11 pages, 4 figures, 1 tabl

    After-hours colorectal surgery: a risk factor for anastomotic leakage

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    __Purpose:__ This study aims to increase knowledge of colorectal anastomotic leakage by performing an incidence study and risk factor analysis with new potential risk factors in a Dutch tertiary referral center. __Methods:__ All patients whom received a primary colorectal anastomosis between 1997 and 2007 were selected by means of operation codes. Patient records were studied for population description and risk factor analysis. __Results:__ In total 739 patients were included. Anastomotic leakage (AL) occurred in 64 (8.7%) patients of whom nine (14.1%) died. Median interval between operation and diagnosis was 8 days. The risk for AL was higher as the anastomoses were constructed more distally (p = 0.019). Univariate analysis showed duration of surgery (p = 0.038), BMI (p = 0.001), time of surgery (p = 0.029), prophylactic drainage (p = 0.006) and time under anesthesia (p = 0.012) to be associated to AL. Multivariate analysis showed BMI greater than 30 kg/m2(p = 0.006; OR 2.6 CI 1.3-5.2) and "after hours" construction of an anastomosis (p = 0.030; OR 2.2 CI 1.1-4.5) to be independent risk factors. __Conclusion:__ BMI greater than 30 kg/m2and "after hours" construction of an anastomosis were independent risk factors for colorectal anastomotic leakage

    Helicobacter Genotyping and Detection in Peroperative Lavage Fluid in Patients with Perforated Peptic Ulcer

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    Introduction and Objectives Certain Helicobacter pylori genotypes are associated with peptic ulcer disease; however, little is known about associations between the H. pylori genotype and perforated peptic ulcer (PPU). The primary aim of this study was to evaluate which genotypes are present in patients with PPU and which genotype is dominant in this population. The secondary aim was to study the possibility of determining the H. pylori status in a way other than by biopsy. Materials and Methods Serum samples, gastric tissue biopsies, lavage fluid, and fluid from the nasogastric tube were collec

    Day and night surgery: is there any influence in the patient postoperative period of urgent colorectal intervention?

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    Background Medical activity performed outside regular work hours may increase risk for patients and professionals. There is few data with respect to urgent colorectal surgery. The aim of this work was to evaluate the impact of daytime versus nighttime surgery on postoperative period of patients with acute colorectal disease. Methods A retrospective study was conducted in a sample of patients with acute colorectal disease who underwent urgent surgery at the General Surgery Unit of Braga Hospital, between January 2005 and March 2013. Patients were stratified by operative time of day into a daytime group (surgery between 8:00 and 20:59) and the nighttime group (21:00–7:59) and compared for clinical and surgical parameters. A questionnaire was distributed to surgeons, covering aspects related to the practice of urgent colorectal surgery and fatigue. Results A total of 330 patients were included, with 214 (64.8 %) in the daytime group and 116 (35.2 %) in the nighttime group. Colorectal cancer was the most frequent pathology. Waiting time (p?<?0.001) and total length of hospital stay (p?=?0.008) were significantly longer in the daytime group. There were no significant differences with respect to early or late complications. However, 100 % of surgeons reported that they are less proficient during nighttime. Conclusions Among patients with acute colorectal disease subjected to urgent surgery, there was no significant association between nighttime surgery and the presence of postoperative medical and surgical morbidities. Patients who were subjected to daytime surgery had longer length of stay at the hospital
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