Learning Environmental Field Exploration with Computationally Constrained Underwater Robots: Gaussian Processes Meet Stochastic Optimal Control.

Autonomous exploration of environmental fields is one of the most promising tasks to be performed by fleets of mobile underwater robots. The goal is to maximize the information gain during the exploration process by integrating an information-metric into the path-planning and control step. Therefore, the system maintains an internal belief representation of the environmental field which incorporates previously collected measurements from the real field.

Embedded Spherical Localization for Micro Underwater Vehicles Based on Attenuation of Electro-Magnetic Carrier Signals.

Self-localization is one of the most challenging problems for deploying micro autonomous underwater vehicles ( μ AUV) in confined underwater environments. This paper extends a recently-developed self-localization method that is based on the attenuation of electro-magnetic waves, to the μ AUV domain. We demonstrate a compact, low-cost architecture that is able to perform all signal processing steps present in the original method.

Regulation of coronary venular barrier function by blood borne inflammatory mediators and pharmacological tools: insights from novel microvascular wall models.

We hypothesized that postcapillary venules play a central role in the control of the tightness of the coronary system as a whole, particularly under inflammatory conditions. Sandwich cultures of endothelial cells and pericytes of precapillary arteriolar or postcapillary venular origin from human myocardium as models of the respective vascular walls (sandwich cultures of precapillary arteriolar or postcapillary venular origin) were exposed to thrombin and components of the acutely activatable inflammatory system, and their hydraulic conductivity (L(P)) was registered. L(P) of SC-PAO remained low under all conditions (3.

Homograft implantation for aortic valve replacement since 15 years: results and follow-up.

Background: The use of homografts in aortic valve replacement is an alternative to other prostheses and has been established in our department for 15 years.

Methods: Since 1992, 360 homografts (HG) have been implanted in adult patients (mean age 51.6 years, 72.

Partial avulsion of prosthetic aortic valve caused by S. epidermidis infection resulting in a giant false aneurysm of the complete thoracic aorta.

A 69-year-old man was presented with a holosystolic and early diastolic murmur in cardiac auscultation, pretibial edema and elevated inflammation markers. Aortic valve and ascending aorta had been replaced 9 months earlier. Transesophageal echocardiography revealed massive eccentric regurgitation and dehiscence of the aortic valve, resulting in a giant circular false aneurysm with connection to the lumen of the aortic arch.