Search results for "Poster"
showing 10 items of 679 documents
On the checking of g-coherence of conditional probability bounds
2003
We illustrate an approach to uncertain knowledge based on lower conditional probability bounds. We exploit the coherence principle of de Finetti and a related notion of generalized coherence (g-coherence), which is equivalent to the "avoiding uniform loss" property introduced by Walley for lower and upper probabilities. Based on the additive structure of random gains, we define suitable notions of non relevant gains and of basic sets of variables. Exploiting them, the linear systems in our algorithms can work with reduced sets of variables and/or constraints. In this paper, we illustrate the notions of non relevant gain and of basic set by examining several cases of imprecise assessments d…
OLS Identification of network topologies
2011
Abstract In many applications, it is important to derive information about the topology and the internal connections of more dynamical systems interacting together. Examples can be found in fields as diverse as Economics, Neuroscience and Biochemistry. The paper deals with the problem of deriving a descriptive model of a network, collecting the node outputs as time series with no use of a priori insight on the topology. We cast the problem as the optimization of a cost function where a set of parameters are used to operate a trade-off between accuracy and complexity in the final model. The problem of reducing the complexity is addressed by fixing a certain degree of sparsity and finding the…
Dynamics of CXC group chemokine platelet factor 4 (PF4) plasma levels in non-small cell lung cancer (NSCLC)
2012
CXC chemokines display pleiotropic effects participating not only in inflammation, but regulating angiogenesis and metastatic spread in cancer. Platelet factor 4 (PF4) is a 70-amino acid protein belonging to the CXC chemokine family. PF4 is also known as CXCL4. This chemokine is released from alpha-granules of activated platelets and binds with high affinity to heparin-like molecules promoting coagulation. Megakaryocytes respond to the presence of tumors by increasing their number in the bone marrow accompanied by increase in the number of platelets in circulation, causing changes in chemokine balance.
Integration of different cardiac electrophysiological models into a single simulation pipeline
2012
Clinical translation of computational models of the heart has been hampered by the absence of complete and rigorous technical and clinical validation, as well as benchmarking of the developed tools. To address this issue, a dataset containing the cardiac anatomy and fibre orientations from magnetic resonance images (MRI), as well as epicardial transmembrane potentials from optical mapping acquired on ex-vivo porcine hearts, have previously been made available to the community. Image processing techniques were developed to integrate MRI images with electrical information. Different models were tested and compared with the integrated data1, including: i) a new methodology to customize and reg…
Synaptic Scaling Enables Dynamically Distinct Short- and Long-Term Memory Formation
2013
Memory storage in the brain relies on mechanisms acting on time scales from minutes, for long-term synaptic potentiation, to days, for memory consolidation. During such processes, neural circuits distinguish synapses relevant for forming a long-term storage, which are consolidated, from synapses of short-term storage, which fade. How time scale integration and synaptic differentiation is simultaneously achieved remains unclear. Here we show that synaptic scaling – a slow process usually associated with the maintenance of activity homeostasis – combined with synaptic plasticity may simultaneously achieve both, thereby providing a natural separation of short- from long-term storage. The inter…
Recent Advances in Digital Holographic Microscopy
2018
In digital holographic microscopy (DHM) a hologram is captured in the image space provided by a microscope. The transfer of the phase and amplitude structure in the original sample to the hologram is in fact strongly affected by the use of the imaging microscope. A big research effort has been devoted to correct these distortions both by numerical and optical compensation. In this contribution, we present several proposals to improve the performance of classical DHM architectures by an a priori approach to compensate physically these perturbations. Experimental results are also presented to validate the proposed techniques.
Difficulties in distinguishing between an atlas fracture and a congenital posterior atlas arch defect in postmortem analysis.
2013
We found one atlas from a sample of 148 skeletons (0.67%) that presented different anatomical variations which made it difficult to determine whether the vertebra had an atlas fracture, an unusual Type B posterior atlas arch defect, or a combination of both. We carried out a stereomicroscopy, radiographic, and computerized tomography scan study that revealed that the dry atlas we found presented a very uncommon congenital Type B posterior atlas arch defect, simulating a fracture. In short, the present paper has revealed that differentiating Type B posterior atlas arch defects from fractures in post-mortem dry vertebrae is more difficult than expected. Thus we believe that it can be easier t…
Early Auditory Evoked Potentials (EAEP) in Neurosurgery — A New Method for Diagnosis and Localization of Posterior Fossa Tumors in Childhood
1983
Auditory stimuli of suprathreshold intensity (above 60 dBHL) evoke about 15 waves: an early series (EAEP) during the initial 10 milliseconds (ms), a middle latency sequence (8 to 50 ms) and the longer latency cortical potentials (50 – 300 ms). PICTON et al. (1974) made a survey of all three potential groups. Only the EAEP (waves I to IV) are generated in the infratentorial part of the brain and reflect progressive activation of the auditory tracts and nuclei (Fig. 1): Wave I is assumed to originate at the distal part of the acoustic nerve, wave II in the medulla, wave III in the caudal and wave IV in the rostral pons and wave V in the midbrain (STARR and ACHOR, 1975; STOCKARD and ROSSITER, …
How to avoid collision between PCL and MCL femoral tunnels during a simultaneous reconstruction.
2014
PURPOSE: The purpose of the present study was to assess the risk of femoral tunnel collisions between the medial collateral ligament (MCL) and the posterior cruciate ligament (PCL) tunnels during a simultaneous PCL and MCL reconstruction. METHODS: Fourth generation medium and large synthetic femur bones were used. On each femur, a MCL tunnel and a PCL tunnel were reamed. The MCL tunnel was drilled at 0°, 20° and 40° of axial and coronal angulations. The PCL femoral tunnel was reamed to simulate two different tunnel directions that could be obtained through an inside-out and outside-in technique. Tunnels were filled with epoxy resin augmented with BaSO4, and a multidetector CT examination of…
Wilson maxillary curve analyzed by cbct a study on normocclusion and malocclusion individuals
2013
The anatomy of dental compensation curve in the frontal plane described by George H. Wilson is one of the occlusal determinants of orthodontic treatment. However, there is few published comparing malocclusion and normocclusion individuals. Objectives: The aim of this study is to compare the curve of Wilson at first and second maxillary molars, normocclusion pattern and malocclusion pattern, with and without bilateral posterior crossbite, using angular references in CBCT studies. Material and Methods: We analyzed 10 cases of malocclusion with bilateral posterior crossbite, 10 cases of malocclusion without bilateral posterior crossbite and 10 cases with non orthodontic normocclusion (patients…