767 research outputs found

    Jumps: Enhancing hop-count positioning in sensor networks using multiple coordinates

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    Positioning systems in self-organizing networks generally rely on measurements such as delay and received signal strength, which may be difficult to obtain and often require dedicated equipment. An alternative to such approaches is to use simple connectivity information, that is, the presence or absence of a link between any pair of nodes, and to extend it to hop-counts, in order to obtain an approximate coordinate system. Such an approximation is sufficient for a large number of applications, such as routing. In this paper, we propose Jumps, a positioning system for those self-organizing networks in which other types of (exact) positioning systems cannot be used or are deemed to be too costly. Jumps builds a multiple coordinate system based solely on nodes neighborhood knowledge. Jumps is interesting in the context of wireless sensor networks, as it neither requires additional embedded equipment nor relies on any nodes capabilities. While other approaches use only three hop-count measurements to infer the position of a node, Jumps uses an arbitrary number. We observe that an increase in the number of measurements leads to an improvement in the localization process, without requiring a high dense environment. We show through simulations that Jumps, when compared with existing approaches, reduces the number of nodes sharing the same coordinates, which paves the way for functions such as position-based routing

    Efficacy and safety of eslicarbazepine acetate monotherapy in patients converting from carbamazepine.

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    OBJECTIVE: To evaluate the influence of prior use of carbamazepine (CBZ) and other antiepileptic drugs (AEDs) with a putatively similar mechanism of action (inhibition of voltage-gated sodium channels; VGSCs) on seizure outcomes and tolerability when converting to eslicarbazepine acetate (ESL), using data pooled from 2 controlled conversion-to-ESL monotherapy trials (studies: 093-045, 093-046). METHODS: Adults with treatment-resistant focal (partial-onset) seizures were randomized 2:1 to ESL 1600 or 1200 mg once daily. The primary efficacy endpoint was study exit (meeting predefined exit criteria related to worsening seizure control) versus an historical control group. Other endpoints included change in seizure frequency, responder rate, and tolerability. Endpoints were analyzed for subgroups of patients who received CBZ (or any VGSC inhibitor [VGSCi]) during baseline versus those who received other AEDs. RESULTS: Of 365 patients in the studies, 332 were evaluable for efficacy. The higher risk of study exit in the subgroups that received CBZ (or any VGSCi) during baseline, versus other AEDs, was not statistically significant (hazard ratios were 1.49 for +CBZ vs -CBZ [P = .10] and 1.27 for +VGSCi vs. -VGSCi [P = .33]). Reductions in seizure frequency and responder rates were lower in patients who converted from CBZ or other VGSCi compared with those who converted from other AEDs. There were no notable differences in overall tolerability between subgroups, but the incidence of some adverse events (eg, dizziness, somnolence, nausea) differed between subgroups and/or between treatment periods. SIGNIFICANCE: Baseline use of CBZ or other major putative VGSC inhibitors did not appear to significantly increase the risk of study exit due to worsening seizure control, or to increase the frequency of side effects when converting to ESL monotherapy. However, bigger improvements in efficacy may be possible in patients converting to ESL monotherapy from an AED regimen that does not include a VGSC inhibitor

    The importance of semiological information based on epileptic seizure history

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    Semiology is the backbone of any correct categorization of seizures, as epileptic or not, focal or bilateral, and is fundamental to elucidating how they are anatomically generated in the brain. An anatomical hypothesis derived from seizure history is the precondition for optimally designed ancillary studies. Without understanding seizure semiology, no rational therapy is possible. This article describes the semiological approach using patient history based on full use of patients’ self-reports as well as descriptions by witnesses. Auras represent the subjective aspects of seizures and provide important semiological clues as observable signs, sometimes including rather precise direct anatomical information. Methods of extracting, facilitating and analysing self-reports including linguistic conversation analysis are presented in detail. It is highlighted that prodromes, seizure triggers and reflex epileptic mechanisms can provide crucial information for diagnostics and therapy. Special issues considering seizure semiology in children are discussed in a separate section. Other sections are dedicated to the two most important issues of differential diagnosis: how to distinguish (1) focal from “generalized” epilepsies, particularly when focal seizure phenomena appear in a bilateral epilepsy; and (2) epileptic from a series of non-epileptic events

    Indução de gemas axilares de cajazeira (Spondias mombin L.) sob condições in vitro.

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    Este estudo tem por objetivo avaliar condicoes de desinfestacao que reduzam a incidencia de contaminantes e nao afetem as taxas de inducao de gemas e de formacao de brotos axilares em segmentos nodais de cajazeira.bitstream/CNPAT-2010/5392/1/Pa-061.pd
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