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Molecular imaging is an emerging imaging technique in biological and medical field. Thereinto, bioluminescence tomography (BLT) plays a significant role. In view of the ill-posedness of the BLT problem, a priori knowledge is indispensable to reconstruct bioluminescent source uniquely and quantitatively. In this paper, the anatomical information of a real mouse is obtained with the microCT scanner...
The vascular geometry may play an important role in the development of atherosclerosis by modulating the local hemodynamics and mechanical stresses of the vessel wall. The mouse is now the most popular animal model to study cardiovascular disease. Here, we present a method to characterize the 3-D geometry of mouse aortic arches by casting and light stereo-microscopic imaging. After calibration of...
We report about two-photon activation of a photoactivatable derivative of the Aequorea Victoria green fluorescent protein (paGFP). This special form of the molecule increases its fluorescence intensity when excited by 488 nm after irradiation with high intensity light at 413 nm. The aim in this work was to evaluate the use of two-photon interactions for confining the molecular switching of pa-GFP...
Recent research and development activity is described in the field of textile-based wearable systems for personalized health care. Sensorized shirts for vital signs monitoring and wearable systems for gesture and posture recognition are specifically illustrated, resulting from the EU funded project My Heart.
Innovative concepts for prevention and disease management of cardio-vascular disease are being developed in the framework of MyHeart project. After a successful first phase where 16 different concepts were tested, four of them where selected on the basis of user acceptance, technical feasibility and foreseen impact. The present paper gives an overview of such product-concepts that are being implemented...
In the Western World, Cardiovascular Diseases (CVD) are the leading source of death. Only in Europe, they cause 45% of all deaths. Besides Heart Failure, the paradigm of CVD, affects mainly people older than 65. Facing this reality, the European Union has funded MyHeart Project, whose mission is empowering citizens to fight CVD by means of a preventive lifestyle and an early diagnosis. This paper...
In this paper, we demonstrate a method for fast registration of sequences of 3D liver images, which could be used for the future real-time applications. In our method, every image is elastically registered to a so called fixed ultrasound image exploiting the information from previous registration. A few feature points are automatically selected, and tracked inside the images, while the deformation...
This paper proposes 2D active contour approach for segmenting thrombus volume from 3D CT images of abdominal aortic aneurysm (AAA). The major challenges in segmenting thrombus are in part because of lack of delineating contrast at anatomical boundaries due to overlap of other soft tissues and artifacts arising from stents and calcium deposits. In the present approach first the bone structures are...
A needle-positioning robot has been developed for image-guided interventions in small animals. The device is designed to position a needle with an error ?? 100 ??m. The robot has two rotational axes (pitch and roll) to control needle orientation, and one linear axis to perform needle insertion. The three axes intersect at a single point, creating a remote center of motion. Needle positioning error...
This paper presents a phantom study that was conducted for an ultrasound-guided shoulder arthroscopy navigation system. The navigation system uses a surface model generated from pre-operative computed tomography images, which has to be registered to the patient during the procedure. The goal of this study was to determine the optimal regions on the scapula bone of the shoulder to achieve an acceptable...
Patient-specific models of the biomechanics of the breast based on finite deformation theory is potentially a valuable tool to assist clinicians in assimilating and assessing information obtained from different views of the breast, under different loading conditions and using different imaging modalities. It is anticipated that a computational model of the large deformation mechanics of the breast...
A multitude of biological rhythms have been identified in the whole organism as well as within each living cell. Some of these rhythms reflect adaptations to our environment, while others run on their own. Recent evidence shows that these rhythms and their interaction might be more important not only for recreation but also for our health. Disturbance of the circadian rhythms by jet lag or shift work...
Heart rate variability (HRV) patterns reflect the changing sympathetic and parasympathetic modulation of the autonomic nervous system. While overall and circadian heart rate (HR) and HRV are well characterized by traditional measures, ultradian cycles of HR and HRV are not. We have developed a method for capturing these rhythms during sleep and have now applied it to 24-hour recordings. Methods: HR/HRV...
Autonomic Information Flow (AIF) reflects the time scale dependence of autonomic communications such as vagal, sympathetic, and slower rhythms and their complex interplay. We investigated the hypothesis that pathologically disturbed short term control is associated with simplified complex long term control. This particular characteristic of altered autonomic communication was evaluated in different...
Contemporary measurement techniques enable noninvasive observations of cardiovascular functions, both from the central and peripheral points of view. Cardiovascular dynamics is found to be characterised by several distinct frequency components, and these are present at each site of the system. The corresponding oscillatory processes are mutually dependent via couplings that lead to amplitude/frequency...
We discuss the usage of the coupled oscillators approach in analysis of bivariate physiological data, taking the cardio-respiratory interaction as an example. These model-based techniques allow us to detect and quantify the strength and directionality of weak interaction, as well as to estimate the delay(s) in coupling. We present both theoretical description of the technique and its algorithmic implementation.
We review recent attempts to understand the influence of sleep and wake states, sleep-stage transitions during sleep and the endogenous circadian rhythms on the neuroautonomic regulation of cardiac dynamics as represented by the scale-invariant organization of heartbeat fluctuations. We find that the probability distribution, the long-range temporal correlations as well as the nonlinear properties...
Aim of the study was to test the reproducibility of estimates of static, ??s, and dynamic, ??d, ??-cell sensitivity to glucose, and predictions of the insulin secretion rate, SR(t), provided by the C-peptide oral minimal model (COMM) applied to oral glucose tolerance tests (OGTT) of various complexity. The study involved six volunteer, normotensive and normoglycemic subjects who underwent a 300-minute...
A robust control design on frequency domain using Mathematica is presented for regularization of glucose level in Type I diabetes persons under intensive care. The method originally proposed under Mathematica by Helton and Merino, [1] - now with an improved disturbance rejection constraint inequality - is employed, using the three-state minimal patient model of [2]. The robustness of the resulted...
In this paper the technique of nonlinear dielectric spectroscopy is employed to examine the nonlinear response of a suspension of the yeast S. cerevisiae to a low frequency perturbating ac electric field. Metabolically active and resting yeast states, as well as the electrolyte medium are considered, and experimental time-course spectral data are presented. Conductivity is found to increase in the...
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