996 resultados para Transient Wave Groups
Resumo:
Nykyaikaisessa liiketoimintaympäristössä yritysten kriittisiksi resursseiksi ovat muodostuneet liiketoimintaa tukevat tietojärjestelmät. Mahdollisuus hyödyntää näitä resursseja riippuu ko. liiketoiminnalle kriittisten järjestelmien luotettavuudesta ja hyödynnettävien sovellusten saatavuudesta. Eräs tilanne jossa järjestelmien kyky tukea todellisia liiketoimintaprosesseja vaarantuu on katastrofi. Vaikutukseltaan katastrofi voi olla paikallinen tai kattaa laajojakin alueita. Eri tyyppisiin katastrofeihin on varauduttava niiden edellyttämin tavoin. Eräs kriittisten tietojärjestelmien arkkitehtuuriin vaikuttanut trendi 90-luvulla on ollut client/server lähestymistapa. Client/server paradigman mukaan sovellus jaetaan tasoihin siten että esitys-, sovellus- ja tietokantakerrokset voidaan erottaa fyysisesti toisistaan näiden silti muodostaessa loogisesti yhtenäisen kokonaisuuden. Liiketoiminnan näkökulmasta 90- luvun mullistavia IT-uutuuksia olivat toiminnanohjausjärjestelmät, joiden avulla oli mahdollista hallita koko tuotantoketjua ja muita prosessikokonaisuuksia lähes reaaliajassa. Monikerroksisten toiminnanohjausjärjestelmien luotettavuus on osoittautunut haastavavaksi sillä kaikkien kerrosten suojaaminen kaikilta mahdollisilta katastrofeilta täydellisesti on nykyisellä teknologialla mahdotonta. Kompromissien tekemiseksi on oltava selvillä kunkin menetetyn prosessin aiheuttamista taloudellisista ja liiketoiminnallisista vaikutuksista. Tämän vuoksi juuri toiminnanohjausjärjestelmät ovat mielenkiintoisia, vaikuttavathan ne liiketoimintaprosesseihin läpi koko yrityksen prosessiketjun. Monikerroksisten client/server arkkitehtuuriin pohjautuvien toiminnanohjausjärjestelmien suojaamisessa katastrofeilta onkin sovellettava useita tekniikoita ja teknologioita, ja yhdistettävä kokonaisuus prosessikehykseen. Näin voidaan luoda suunnitelmallinen osa IT strategiaa, joka ottaa kantaa liiketoiminnan jatkuvuuteen katastrofitilanteessa ja mahdollistaa nopean ja täydellisen palautumisen kaikissa olosuhteissa.
Resumo:
BACKGROUND: Studies in bipolar disorder (BD) to date are limited in their ability to provide a whole-disease perspective--their scope has generally been confined to a single disease phase and/or a specific treatment. Moreover, most clinical trials have focused on the manic phase of disease, and not on depression, which is associated with the greatest disease burden. There are few longitudinal studies covering both types of patients with BD (I and II) and the whole course of the disease, regardless of patients' symptomatology. Therefore, the Wide AmbispectiVE study of the clinical management and burden of Bipolar Disorder (WAVE-bd) (NCT01062607) aims to provide reliable information on the management of patients with BD in daily clinical practice. It also seeks to determine factors influencing clinical outcomes and resource use in relation to the management of BD. METHODS: WAVE-bd is a multinational, multicentre, non-interventional, longitudinal study. Approximately 3000 patients diagnosed with BD type I or II with at least one mood event in the preceding 12 months were recruited at centres in Austria, Belgium, Brazil, France, Germany, Portugal, Romania, Turkey, Ukraine and Venezuela. Site selection methodology aimed to provide a balanced cross-section of patients cared for by different types of providers of medical aid (e.g. academic hospitals, private practices) in each country. Target recruitment percentages were derived either from scientific publications or from expert panels in each participating country. The minimum follow-up period will be 12 months, with a maximum of 27 months, taking into account the retrospective and the prospective parts of the study. Data on demographics, diagnosis, medical history, clinical management, clinical and functional outcomes (CGI-BP and FAST scales), adherence to treatment (DAI-10 scale and Medication Possession Ratio), quality of life (EQ-5D scale), healthcare resources, and caregiver burden (BAS scale) will be collected. Descriptive analysis with common statistics will be performed. DISCUSSION: This study will provide detailed descriptions of the management of BD in different countries, particularly in terms of clinical outcomes and resources used. Thus, it should provide psychiatrists with reliable and up-to-date information about those factors associated with different management patterns of BD. TRIAL REGISTRATION NO: ClinicalTrials.gov: NCT01062607.
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In this paper we design and develop several filtering strategies for the analysis of data generated by a resonant bar gravitational wave (GW) antenna, with the goal of assessing the presence (or absence) therein of long-duration monochromatic GW signals, as well as the eventual amplitude and frequency of the signals, within the sensitivity band of the detector. Such signals are most likely generated in the fast rotation of slightly asymmetric spinning stars. We develop practical procedures, together with a study of their statistical properties, which will provide us with useful information on the performance of each technique. The selection of candidate events will then be established according to threshold-crossing probabilities, based on the Neyman-Pearson criterion. In particular, it will be shown that our approach, based on phase estimation, presents a better signal-to-noise ratio than does pure spectral analysis, the most common approach.
Resumo:
OBJECTIVE: In contrast to conventional (CONV) neuromuscular electrical stimulation (NMES), the use of "wide-pulse, high-frequencies" (WPHF) can generate higher forces than expected by the direct activation of motor axons alone. We aimed at investigating the occurrence, magnitude, variability and underlying neuromuscular mechanisms of these "Extra Forces" (EF). METHODS: Electrically-evoked isometric plantar flexion force was recorded in 42 healthy subjects. Additionally, twitch potentiation, H-reflex and M-wave responses were assessed in 13 participants. CONV (25Hz, 0.05ms) and WPHF (100Hz, 1ms) NMES consisted of five stimulation trains (20s on-90s off). RESULTS: K-means clustering analysis disclosed a responder rate of almost 60%. Within this group of responders, force significantly increased from 4% to 16% of the maximal voluntary contraction force and H-reflexes were depressed after WPHF NMES. In contrast, non-responders showed neither EF nor H-reflex depression. Twitch potentiation and resting EMG data were similar between groups. Interestingly, a large inter- and intrasubject variability of EF was observed. CONCLUSION: The responder percentage was overestimated in previous studies. SIGNIFICANCE: This study proposes a novel methodological framework for unraveling the neurophysiological mechanisms involved in EF and provides further evidence for a central contribution to EF in responders.
Resumo:
The synthesis of various polycyclic systems containing a C3a-Ni bond between a hexahydropyrrolo[2,3-b]indole and an indole tryptophan is described here. A series of experiments were performed to determine the best combination of five orthogonal protecting groups and the best reaction conditions for formation of said bond, which is a common feature among many recently discovered marine natural products.
Resumo:
[spa] En este trabajo se analiza la relación entre la heterogeneidad étnica y la redistribución, utilizando la reciente y masiva llegada de inmigrantes a España. En concreto, se estudia el efecto de los cambios en la densidad de inmigrantes, observada entre 1998 y 2006, sobre los cambios en el gasto social municipal. La densidad de inmigrantes se instrumenta utilizando los patrones de establecimiento por país de origen para asignar los flujos predichos de inmigrantes a cada municipio. Los resultados evidencian que el gasto social incrementó menos en los municipios con mayores incrementos en la densidad de inmigrantes. También se proporciona evidencia de la existencia de una relación positiva entre la densidad de inmigrantes y el porcentaje de voto obtenidos por los partidos de derecha. Por tanto, estos resultados son consistentes con las teorías que predicen una relación negativa entre la heterogeneidad étnica y la redistribución.
Resumo:
[spa] En este trabajo se analiza la relación entre la heterogeneidad étnica y la redistribución, utilizando la reciente y masiva llegada de inmigrantes a España. En concreto, se estudia el efecto de los cambios en la densidad de inmigrantes, observada entre 1998 y 2006, sobre los cambios en el gasto social municipal. La densidad de inmigrantes se instrumenta utilizando los patrones de establecimiento por país de origen para asignar los flujos predichos de inmigrantes a cada municipio. Los resultados evidencian que el gasto social incrementó menos en los municipios con mayores incrementos en la densidad de inmigrantes. También se proporciona evidencia de la existencia de una relación positiva entre la densidad de inmigrantes y el porcentaje de voto obtenidos por los partidos de derecha. Por tanto, estos resultados son consistentes con las teorías que predicen una relación negativa entre la heterogeneidad étnica y la redistribución.
Resumo:
n this work we analyze the behavior of complex information in Fresnel domain taking into account the limited capability to display complex transmittance values of current liquid crystal devices, when used as holographic displays. In order to do this analysis we compute the reconstruction of Fresnel holograms at several distances using the different parts of the complex distribution (real and imaginary parts, amplitude and phase) as well as using the full complex information adjusted with a method that combines two configurations of the devices in an adding architecture. The RMS error between the amplitude of these reconstructions and the original amplitude is used to evaluate the quality of the information displayed. The results of the error analysis show different behavior for the reconstructions using the different parts of the complex distribution and using the combined method of two devices. Better reconstructions are obtained when using two devices whose configurations densely cover the complex plane when they are added. Simulated and experimental results are also presented.
Resumo:
Probabilistic inversion methods based on Markov chain Monte Carlo (MCMC) simulation are well suited to quantify parameter and model uncertainty of nonlinear inverse problems. Yet, application of such methods to CPU-intensive forward models can be a daunting task, particularly if the parameter space is high dimensional. Here, we present a 2-D pixel-based MCMC inversion of plane-wave electromagnetic (EM) data. Using synthetic data, we investigate how model parameter uncertainty depends on model structure constraints using different norms of the likelihood function and the model constraints, and study the added benefits of joint inversion of EM and electrical resistivity tomography (ERT) data. Our results demonstrate that model structure constraints are necessary to stabilize the MCMC inversion results of a highly discretized model. These constraints decrease model parameter uncertainty and facilitate model interpretation. A drawback is that these constraints may lead to posterior distributions that do not fully include the true underlying model, because some of its features exhibit a low sensitivity to the EM data, and hence are difficult to resolve. This problem can be partly mitigated if the plane-wave EM data is augmented with ERT observations. The hierarchical Bayesian inverse formulation introduced and used herein is able to successfully recover the probabilistic properties of the measurement data errors and a model regularization weight. Application of the proposed inversion methodology to field data from an aquifer demonstrates that the posterior mean model realization is very similar to that derived from a deterministic inversion with similar model constraints.
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BACKGROUND: Cranial nerve schwannomas are radiologically characterized by nodular cranial nerve enhancement on magnetic resonance imaging (MRI). Schwannomas typically present with gradually progressive symptoms, but isolated reports have suggested that schwannomas may cause fluctuating symptoms as well. METHODS: This is a report of ten cases of presumed cranial nerve schwannoma that presented with transient or recurring ocular motor nerve deficits. RESULTS: Schwannomas of the third, fourth, and fifth nerves resulted in fluctuating deficits of all 3 ocular motor nerves. Persistent nodular cranial nerve enhancement was present on sequential MRI studies. Several episodes of transient oculomotor (III) deficts were associated with headaches, mimicking ophthalmoplegic migraine. CONCLUSIONS: Cranial nerve schwannomas may result in relapsing and remitting cranial nerve symptoms.
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Addition of a 50 mM mixture of l-arginine and l-glutamic acid (RE) is extensively used to improve protein solubility and stability, although the origin of the effect is not well understood. We present Small Angle X-ray Scattering (SAXS) and Nuclear Magnetic Resonance (NMR) results showing that RE induces protein compaction by collapsing flexible loops on the protein core. This is suggested to be a general mechanism preventing aggregation and improving resistance to proteases and to originate from the polyelectrolyte nature of RE. Molecular polyelectrolyte mixtures are expected to display long range correlation effects according to dressed interaction site theory. We hypothesize that perturbation of the RE solution by dissolved proteins is proportional to the volume occupied by the protein. As a consequence, loop collapse, minimizing the effective protein volume, is favored in the presence of RE.
Histologic evaluation of thermal damage produced on soft tissues by CO2, Er,Cr:YSGG and diode lasers
Resumo:
Objective: The aim of this in vitro experimental study was to perform histological evaluation of the thermal effect produced on soft tissue irradiated with CO2, Er,Cr:YSGG or diode lasers. Study design: Porcine oral mucosa samples were irradiated with Er,Cr:YSGG laser at 1 W with and without water / air spray, at 2 W with and without water / air spray, and at 4 W with water / air spray, with CO2 laser at 1 W, 2 W, 10 W, 20 W continuous mode and 20 W pulsed mode and diode laser at 2W, 5W, and 10W pulsed mode. The thermal effect was evaluated measuring the width of damaged tissue adjacent to the incision, stained positively for hyalinized tissue with Hematoxylin-Eosin and Masson Trichrome stains. Besides, histological changes in the irradiated tissue were described using subjective grading scales. Results: The evaluated lasers developed a wide range of thermal damage with significant differences between groups. The samples with lowest thermal effect were those irradiated with Er,Cr:YSGG laser using water / air spray, followed by CO2 and diode lasers. Conclusions: Emission parameters of each laser system may influence the thermal damage inflicted on the soft tissue, however, the wave length of each laser determines the absorption rate characteristics of every tissue and the thermal effect
Resumo:
BACKGROUND: Temporary increases in plasma HIV RNA ('blips') are common in HIV patients on combination antiretroviral therapy (cART). Blips above 500 copies/mL have been associated with subsequent viral rebound. It is not clear if this relationship still holds when measurements are made using newer more sensitive assays. METHODS: We selected antiretroviral-naive patients that then recorded one or more episodes of viral suppression on cART with HIV RNA measurements made using more sensitive assays (lower limit of detection below 50 copies/ml). We estimated the association in these episodes between blip magnitude and the time to viral rebound. RESULTS: Four thousand ninety-four patients recorded a first episode of viral suppression on cART using more sensitive assays; 1672 patients recorded at least one subsequent suppression episode. Most suppression episodes (87 %) were recorded with TaqMan version 1 or 2 assays. Of the 2035 blips recorded, 84 %, 12 % and 4 % were of low (50-199 copies/mL), medium (200-499 copies/mL) and high (500-999 copies/mL) magnitude respectively. The risk of viral rebound increased as blip magnitude increased with hazard ratios of 1.20 (95 % CI 0.89-1.61), 1.42 (95 % CI 0.96-2.19) and 1.93 (95 % CI 1.24-3.01) for low, medium and high magnitude blips respectively; an increase of hazard ratio 1.09 (95 % CI 1.03 to 1.15) per 100 copies/mL of HIV RNA. CONCLUSIONS: With the more sensitive assays now commonly used for monitoring patients, blips above 200 copies/mL are increasingly likely to lead to viral rebound and should prompt a discussion about adherence.