88 research outputs found
Tissue-Informative Mechanism for Wearable Non-invasive Continuous Blood Pressure Monitoring
Accurate continuous direct measurement of the blood pressure is currently available thru direct invasive methods via intravascular needles, and is mostly limited to use during surgical procedures or in the intensive care unit (ICU). Non-invasive methods that are mostly based on auscultation or cuff oscillometric principles do provide relatively accurate measurement of blood pressure. However, they mostly involve physical inconveniences such as pressure or stress on the human body. Here, we introduce a new non-invasive mechanism of tissue-informative measurement, where an experimental phenomenon called subcutaneous tissue pressure equilibrium is revealed and related for application in detection of absolute blood pressure. A prototype was experimentally verified to provide an absolute blood pressure measurement by wearing a watch-type measurement module that does not cause any discomfort. This work is supposed to contribute remarkably to the advancement of continuous non-invasive mobile devices for 24-7 daily-life ambulatory blood-pressure monitoring.open
Peripheral arterial volume distensibility changes with applied external pressure: significant difference between arteries with different compliance
This study aimed to quantify the different effect of external cuff pressure on arterial volume distensibility between peripheral arteries with different compliance. 30 healthy subjects were studied with the arm at two positions (0° and 45° from the horizontal level) to introduce different compliance of arteries. The electrocardiogram and finger and ear photoplethysmograms were recorded simultaneously under five external cuff pressures (0, 10, 20, 30 and 40 mmHg) on the whole arm to obtain arterial volume distensibility. With the applied external cuff pressures of 10, 20, 30 and 40 mmHg, the overall changes in arterial volume distensibility referred to those without external pressure were 0.010, 0.029, 0.054 and 0.108% per mmHg for the arm at the horizontal level, and 0.026, 0.071, 0.170 and 0.389% per mmHg for the arm at 45° from the horizontal level, confirming the non-linearity between arterial volume distensibility and external pressure. More interestingly, the significant differences in arterial volume distensibility changes were observed between the two arm positions, which were 0.016, 0.043, 0.116 and 0.281% per mmHg (all P < 0.01). Our findings demonstrated that arterial volume distensibility of peripheral arm arteries increased with external pressure, with a greater effect for more compliant arteries
The GEYSERS optical testbed: a platform for the integration, validation and demonstration of cloud-based infrastructure services
The recent evolution of cloud services is leading to a new service transformation paradigm to accommodate network infrastructures in a cost-scalable way. In this transformation, the network constitutes the key to efficiently connect users to services and applications. In this paper we describe the deployment, validation and demonstration of the optical integrated testbed for the “GEneralized architecture for dYnamic infrastructure SERviceS” (GEYSERS) project to accommodate such cloud based Infrastructure Services. The GEYSERS testbed is composed of a set of local physical testbeds allocated in the facilities of the GEYSERS partners. It is built up based on the requirements specification, architecture definition and per-layer development that constitutes the whole GEYSERS ecosystem, and validates the procedures on the GEYSERS prototypes. The testbed includes optical devices (layer 1), switches (layer 2), and IT resources deployed in different local testbeds provided by the project partners and interconnected among them to compose the whole testbed layout. The main goal of the GEYSERS testbed is twofold. On one hand, it aims at providing a validation ground for the architecture, concepts and business models proposed by GEYSERS, sustained by two main paradigms: Infrastructure as a Service (IaaS) and the coupled provisioning of optical network and IT resources. On the other hand, it is used as a demonstration platform for testing the software prototypes within the project and to demonstrate to the research and business community the project approach and solutions. In this work, we discuss our experience in the deployment of the testbed and share the results and insights learned from our trials in the process. Additionally, the paper highlights the most relevant experiments carried out in the testbed, aimed at the validation of the overall GEYSERS architecture
Varespladib and cardiovascular events in patients with an acute coronary syndrome: the VISTA-16 randomized clinical trial
IMPORTANCE: Secretory phospholipase A2(sPLA2) generates bioactive phospholipid products implicated in atherosclerosis. The sPLA2inhibitor varespladib has favorable effects on lipid and inflammatory markers; however, its effect on cardiovascular outcomes is unknown. OBJECTIVE: To determine the effects of sPLA2inhibition with varespladib on cardiovascular outcomes. DESIGN, SETTING, AND PARTICIPANTS: A double-blind, randomized, multicenter trial at 362 academic and community hospitals in Europe, Australia, New Zealand, India, and North America of 5145 patients randomized within 96 hours of presentation of an acute coronary syndrome (ACS) to either varespladib (n = 2572) or placebo (n = 2573) with enrollment between June 1, 2010, and March 7, 2012 (study termination on March 9, 2012). INTERVENTIONS: Participants were randomized to receive varespladib (500 mg) or placebo daily for 16 weeks, in addition to atorvastatin and other established therapies. MAIN OUTCOMES AND MEASURES: The primary efficacy measurewas a composite of cardiovascular mortality, nonfatal myocardial infarction (MI), nonfatal stroke, or unstable angina with evidence of ischemia requiring hospitalization at 16 weeks. Six-month survival status was also evaluated. RESULTS: At a prespecified interim analysis, including 212 primary end point events, the independent data and safety monitoring board recommended termination of the trial for futility and possible harm. The primary end point occurred in 136 patients (6.1%) treated with varespladib compared with 109 patients (5.1%) treated with placebo (hazard ratio [HR], 1.25; 95%CI, 0.97-1.61; log-rank P = .08). Varespladib was associated with a greater risk of MI (78 [3.4%] vs 47 [2.2%]; HR, 1.66; 95%CI, 1.16-2.39; log-rank P = .005). The composite secondary end point of cardiovascular mortality, MI, and stroke was observed in 107 patients (4.6%) in the varespladib group and 79 patients (3.8%) in the placebo group (HR, 1.36; 95% CI, 1.02-1.82; P = .04). CONCLUSIONS AND RELEVANCE: In patients with recent ACS, varespladib did not reduce the risk of recurrent cardiovascular events and significantly increased the risk of MI. The sPLA2inhibition with varespladib may be harmful and is not a useful strategy to reduce adverse cardiovascular outcomes after ACS. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01130246. Copyright 2014 American Medical Association. All rights reserved
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Cause of Death and Predictors of All-Cause Mortality in Anticoagulated Patients With Nonvalvular Atrial Fibrillation : Data From ROCKET AF
M. Kaste on työryhmän ROCKET AF Steering Comm jäsen.Background-Atrial fibrillation is associated with higher mortality. Identification of causes of death and contemporary risk factors for all-cause mortality may guide interventions. Methods and Results-In the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF) study, patients with nonvalvular atrial fibrillation were randomized to rivaroxaban or dose-adjusted warfarin. Cox proportional hazards regression with backward elimination identified factors at randomization that were independently associated with all-cause mortality in the 14 171 participants in the intention-to-treat population. The median age was 73 years, and the mean CHADS(2) score was 3.5. Over 1.9 years of median follow-up, 1214 (8.6%) patients died. Kaplan-Meier mortality rates were 4.2% at 1 year and 8.9% at 2 years. The majority of classified deaths (1081) were cardiovascular (72%), whereas only 6% were nonhemorrhagic stroke or systemic embolism. No significant difference in all-cause mortality was observed between the rivaroxaban and warfarin arms (P=0.15). Heart failure (hazard ratio 1.51, 95% CI 1.33-1.70, P= 75 years (hazard ratio 1.69, 95% CI 1.51-1.90, P Conclusions-In a large population of patients anticoagulated for nonvalvular atrial fibrillation, approximate to 7 in 10 deaths were cardiovascular, whereasPeer reviewe
Transient pressure analysis for the reactor core and containment of a HTGR after a primary loop pressure boundary break accident
The Interaction Network Ontology-supported modeling and mining of complex interactions represented with multiple keywords in biomedical literature
Land cover changes in Błędowska Desert area between 1926 and 2005
W artykule przedstawione zostaną wyniki badań dotyczących zmian w pokryciu terenu Pustyni Błędowskiej w latach 1926–2005. Badania przeprowadzono w oparciu o archiwalne i współczesne zobrazowania lotnicze i satelitarne: zdjęcia lotnicze, wykonane w roku 1926, zdjęcia satelitarne systemu CORONA z roku 1968 oraz ortofotomapy lotnicze, wykonane na potrzeby projektu LPIS i wysokorozdzielczą ortofotomapę satelitarną, powstałą z obrazów zarejestrowanych przez satelitę IKONOS w roku 2005. Ocenę rozmiaru zmian oparto na analizie fotointerpretacyjnej obrazów z okresu 1926–2005 oraz przeprowadzonej w środowisku GIS ilościowej analizie przekształceń form użytkowania, jakie zaszły na badanym obszarze od roku 1968. Przeprowadzenie analiz ilościowych wymagało wykonania korekcji geometrycznej archiwalnych zdjęć satelitarnych. W pracy zawarto porównanie wyników korekcji otrzymanych z wykorzystaniem metod wielomianowych: wielomianu stopnia pierwszego i drugiego oraz ilorazowego modelu wielomianowego. Zastosowanie ostatniej z metod pozwoliło na uzyskanie dokładności geometrycznej na poziomie dokładności mapy topograficznej w skali 1:25 000. Analiza fotointerpretacyjna oraz otrzymane w jej wyniku mapy pokrycia terenu „pustyni” i uzyskane na drodze ich analiz zestawienia tabelaryczne pozwoliły ocenić rodzaj i tempo zmian w przeciągu badanych 80 lat. Umożliwiły też ilościowe, szczegółowe oszacowanie ich rozmiaru w ostatnich czterdziestu latach. Ocena rozmiaru zmian, jakie zaszły na przełomie ostatnich 80 lat potwierdza, że Pustynia Błędowska zarasta. Obecnie bardziej przypomina las niż teren, którego fizjonomia jeszcze 40 lat temu była wyjątkowa w skali europejskiej. Roślinność w sposób naturalny pojawiła się na tym obszarze już przed wojną i pod koniec lat 60-tych XX w. zwiększyła obszar swojego występowania. Jednak tempo jej sukcesji w ostatnich czterdziestu latach znacznie wzrosło, w dużej mierze na skutek ingerencji człowieka.The paper presents the results of research on land cover changes in the Błędowska Desert area between 1926 and 2005. The study was based on historical and up-to-date remotely sensed images: aerial photographs from 1926, CORONA satellite photographs from 1968, aerial orthophotos made for LPIS project and high-resolution satellite orthophoto from Ikonos imagery acquired in 2005. The evaluation of land cover changes was done through photo interpretation of images and quantitative analysis in the GIS environment. A rectification of CORONA images was necessary to enable quantitative analysis. A comparison is presented of the correction results achieved with 1st and 2nd order polynomials as well as the rational polynomial method. Geometric accuracy necessary for 1:25000 topographic maps has been achieved using the rational polynomial method. Photo interpretation and the resulting land cover maps of the Błędowska Desert enabled evaluation of land cover changes during the considered 80 years, and a detailed quantitative analysis for the last 40 years. The evaluation of the land cover changes during the last 80 years proves that the Błędowska Desert has being overgrowing. Today the area is more comparable to a forest than to the unique desert area in Europe as it was 40 years ago. The vegetation appeared here in a natural way before World War II and expanded in the late 1960s. But, succession accelerated in the last 40 years, mainly because of human influence
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