Search results for " stream"
showing 10 items of 205 documents
Procalcitonin as a marker of Candida species detection by blood culture and polymerase chain reaction in septic patients
2014
Background: The aim of our study is to test procalcitonin (PCT) as surrogate marker of identification of Candida spp. by blood culture (BC) and real-time-polymerase chain reaction (PCR), whether alone or in association with bacteria, in septic patients.Methods: We performed a single-centre retrospective study. We reviewed the clinical charts of patients with a diagnosis of severe sepsis or septic shock treated at our general intensive care unit from March 2009 to March 2013. We analysed all diagnostic episodes consisting of BC, real-time PCR assay and dosage of PCT. We registered age, sex, white blood count, sequential organ failure assessment score and type of admission between medical or …
Scalable Clustering by Iterative Partitioning and Point Attractor Representation
2016
Clustering very large datasets while preserving cluster quality remains a challenging data-mining task to date. In this paper, we propose an effective scalable clustering algorithm for large datasets that builds upon the concept of synchronization. Inherited from the powerful concept of synchronization, the proposed algorithm, CIPA (Clustering by Iterative Partitioning and Point Attractor Representations), is capable of handling very large datasets by iteratively partitioning them into thousands of subsets and clustering each subset separately. Using dynamic clustering by synchronization, each subset is then represented by a set of point attractors and outliers. Finally, CIPA identifies the…
A Novel Clustering Algorithm based on a Non-parametric "Anti-Bayesian" Paradigm
2015
The problem of clustering, or unsupervised classification, has been solved by a myriad of techniques, all of which depend, either directly or implicitly, on the Bayesian principle of optimal classification. To be more specific, within a Bayesian paradigm, if one is to compare the testing sample with only a single point in the feature space from each class, the optimal Bayesian strategy would be to achieve this based on the distance from the corresponding means or central points in the respective distributions. When this principle is applied in clustering, one would assign an unassigned sample into the cluster whose mean is the closest, and this can be done in either a bottom-up or a top-dow…
A critical review on the implementation of static data sampling techniques to detect network attacks
2021
International audience; Given that the Internet traffic speed and volume are growing at a rapid pace, monitoring the network in a real-time manner has introduced several issues in terms of computing and storage capabilities. Fast processing of traffic data and early warnings on the detected attacks are required while maintaining a single pass over the traffic measurements. To palliate these problems, one can reduce the amount of traffic to be processed by using a sampling technique and detect the attacks based on the sampled traffic. Different parameters have an impact on the efficiency of this process, mainly, the applied sampling policy and sampling ratio. In this paper, we investigate th…
Higher-Fidelity Frugal and Accurate Quantile Estimation Using a Novel Incremental <italic>Discretized</italic> Paradigm
2018
Traditional pattern classification works with the moments of the distributions of the features and involves the estimation of the means and variances. As opposed to this, more recently, research has indicated the power of using the quantiles of the distributions because they are more robust and applicable for non-parametric methods. The estimation of the quantiles is even more pertinent when one is mining data streams. However, the complexity of quantile estimation is much higher than the corresponding estimation of the mean and variance, and this increased complexity is more relevant as the size of the data increases. Clearly, in the context of infinite data streams, a computational and sp…
The Bossons glacier protects Europe's summit from erosion
2013
13 pages; International audience; The contrasting efficiency of erosion beneath cold glacier ice, beneath temperate glacier ice, and on ice-free mountain slopes is one of the key parameters in the development of relief during glacial periods. Detrital geochronology has been applied to the subglacial streams of the north face of the Mont-Blanc massif in order to estimate the efficiency of erosional processes there. Lithologically this area is composed of granite intruded at ~303 Ma within an older polymetamorphic complex. We use macroscopic features (on ~10,000 clasts) and U-Pb dating of zircon (~500 grains) to establish the provenance of the sediment transported by the glacier and its subgl…
Two-dimensional numerical modeling of fracturing and shear band development in glacier fronts
2014
In this contribution we present a two-dimensional numerical model of a deforming glacier front. The model is based on a hybrid lattice spring network approach where particles in the model can deform in a volume conservative visco-elastic manner but at the same time they can be compressed elastically and fracture by discrete failure. We restrict ourselves to a simple setting where the glacier sits on a frictionless slope that dips with 5–10°, the ice block is fixed on one side and has a free surface on the other. The glacier varies in viscosity and can flow at the base, whereas it is brittle at the top. Results show that the head of the glacier is unstable. Failure happens as a combination o…
Migrating neuroblasts of the rostral migratory stream are putative targets for the action of nitric oxide
2007
It has been demonstrated that the gaseous messenger nitric oxide influences cell proliferation and cell migration, and therefore affects adult neurogenesis in mammals. Here, we investigated the putative targets for this action in the rostral migratory stream of the rat. We used immunocytochemical detection of the beta1 subunit of the enzyme soluble guanylyl cyclase, which can be activated by nitric oxide. Our results under light and electron microscopy demonstrated that the migrating neuroblasts (type A cells) were beta1-immunopositive. The astrocytes (type B cells), immature precursors (type C cells) and ependymal cells (type E cells) were beta1-immunonegative. The neurochemical characteri…
Quantitative Bestimmung des Gallenr�ckflusses in Blut und Leberlymphe von Ratten bei beginnender Gallenstauung
1970
1. Mit dem Ziel, die Anteile des bei einer Gallenstauung auftretenden Gallenruckflusses in Blut und Lymphe quantitativ zu erfassen, wurde ein Verfahren zur Gewinnung reiner Leberlymphe bei Ratten entwickelt. 2. Mit Hilfe dieser Methode konnte am Versuchstier mit normaler Korpertemperatur aus Messungen der Lymphstromstarke und des Eiweisgehaltes der Leberlymphe vor und wahrend einer Gallenstauung auf einen Ruckflus der fortlaufenden produzierten Galle in die Leberlymphe von ca. 7–10% geschlossen werden. 3. In Ruckflusversuchen an unterkuhlten Ratten mit Ringerlosung, die Evansblue enthielt, ergaben Analysen von Blut und Leberlymphe einen Anteil des Ruckflusses in diese Lymphe von ca. 13%.