965 resultados para available bandwidth
Resumo:
Genetically constructed microbial biosensors for measuring organic pollutants are mostly applied in aqueous samples. Unfortunately, the detection limit of most biosensors is insufficient to detect pollutants at low but environmentally relevant concentrations. However, organic pollutants with low levels of water solubility often have significant gas-water partitioning coefficients, which in principle makes it possible to measure such compounds in the gas rather than the aqueous phase. Here we describe the first use of a microbial biosensor for measuring organic pollutants directly in the gas phase. For this purpose, we reconstructed a bioluminescent Pseudomonas putida naphthalene biosensor strain to carry the NAH7 plasmid and a chromosomally inserted gene fusion between the sal promoter and the luxAB genes. Specific calibration studies were performed with suspended and filter-immobilized biosensor cells, in aqueous solution and in the gas phase. Gas phase measurements with filter-immobilized biosensor cells in closed flasks, with a naphthalene-contaminated aqueous phase, showed that the biosensor cells can measure naphthalene effectively. The biosensor cells on the filter responded with increasing light output proportional to the naphthalene concentration added to the water phase, even though only a small proportion of the naphthalene was present in the gas phase. In fact, the biosensor cells could concentrate a larger proportion of naphthalene through the gas phase than in the aqueous suspension, probably due to faster transport of naphthalene to the cells in the gas phase. This led to a 10-fold lower detectable aqueous naphthalene concentration (50 nM instead of 0.5 micro M). Thus, the use of bacterial biosensors for measuring organic pollutants in the gas phase is a valid method for increasing the sensitivity of these valuable biological devices.
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We have explored the possibility of obtaining first-order permeability estimates for saturated alluvial sediments based on the poro-elastic interpretation of the P-wave velocity dispersion inferred from sonic logs. Modern sonic logging tools designed for environmental and engineering applications allow one for P-wave velocity measurements at multiple emitter frequencies over a bandwidth covering 5 to 10 octaves. Methodological considerations indicate that, for saturated unconsolidated sediments in the silt to sand range and typical emitter frequencies ranging from approximately 1 to 30 kHz, the observable velocity dispersion should be sufficiently pronounced to allow one for reliable first-order estimations of the permeability structure. The corresponding predictions have been tested on and verified for a borehole penetrating a typical surficial alluvial aquifer. In addition to multifrequency sonic logs, a comprehensive suite of nuclear and electrical logs, an S-wave log, a litholog, and a limited number laboratory measurements of the permeability from retrieved core material were also available. This complementary information was found to be essential for parameterizing the poro-elastic inversion procedure and for assessing the uncertainty and internal consistency of corresponding permeability estimates. Our results indicate that the thus obtained permeability estimates are largely consistent with those expected based on the corresponding granulometric characteristics, as well as with the available evidence form laboratory measurements. These findings are also consistent with evidence from ocean acoustics, which indicate that, over a frequency range of several orders-of-magnitude, the classical theory of poro-elasticity is generally capable of explaining the observed P-wave velocity dispersion in medium- to fine-grained seabed sediments
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The transapical transcatheter aortic valve implantation (TA-TAVI) in degenerated aortic bioprosthesis is an emerging therapy for surgically non-amenable patients. However, the presence of different types of aortic bioprostheses (stented and stentless), available in different sizes (19-27 mm), can be at the origin of important mismatches between the malfunctioning, degenerated aortic valves and the inner stent-valves implanted through transapical accesses (23 and 26 mm Edwards Sapien transcatheter stent-valves). We report an emergency TA-TAVI treatment of a severely regurgitant degenerated 23 mm Mitroflow aortic bioprosthesis (Sorin Group, Milano, Italy) implanted seven years earlier in an 80-year-old lady, and we reviewed the current available literature about transapical 'valve-in-valve' procedures to analyze the hemodynamic results and the ideal 'prosthesis-to-prosthesis' match.
Resumo:
Multisensory interactions have been documented within low-level, even primary, cortices and at early post-stimulus latencies. These effects are in turn linked to behavioral and perceptual modulations. In humans, visual cortex excitability, as measured by transcranial magnetic stimulation (TMS) induced phosphenes, can be reliably enhanced by the co-presentation of sounds. This enhancement occurs at pre-perceptual stages and is selective for different types of complex sounds. However, the source(s) of auditory inputs effectuating these excitability changes in primary visual cortex remain disputed. The present study sought to determine if direct connections between low-level auditory cortices and primary visual cortex are mediating these kinds of effects by varying the pitch and bandwidth of the sounds co-presented with single-pulse TMS over the occipital pole. Our results from 10 healthy young adults indicate that both the central frequency and bandwidth of a sound independently affect the excitability of visual cortex during processing stages as early as 30 msec post-sound onset. Such findings are consistent with direct connections mediating early-latency, low-level multisensory interactions within visual cortices.
Resumo:
Substantial collective flow is observed in collisions between lead nuclei at Large Hadron Collider (LHC) as evidenced by the azimuthal correlations in the transverse momentum distributions of the produced particles. Our calculations indicate that the global v1-flow, which at RHIC peaked at negative rapidities (named third flow component or antiflow), now at LHC is going to turn toward forward rapidities (to the same side and direction as the projectile residue). Potentially this can provide a sensitive barometer to estimate the pressure and transport properties of the quark-gluon plasma. Our calculations also take into account the initial state center-of-mass rapidity fluctuations, and demonstrate that these are crucial for v1 simulations. In order to better study the transverse momentum flow dependence we suggest a new"symmetrized" vS1(pt) function, and we also propose a new method to disentangle global v1 flow from the contribution generated by the random fluctuations in the initial state. This will enhance the possibilities of studying the collective Global v1 flow both at the STAR Beam Energy Scan program and at LHC.
Resumo:
High availability goals and ways to reach them, from a GNU/Linux point of view.
Resumo:
Purpose: To analyze the therapeutic indications for off-label use of rituximab, the available evidence for its use, the outcomes, and the cost. Methods: This was a retrospective analysis of patients treated with rituximab for off-label indications from January 2007 to December 2009 in two tertiary hospitals. Information on patient characteristics, medical conditions, and therapeutic responses was collected from medical records. Available evidence for the efficacy of rituximab in each condition was reviewed, and the cost of treatment was calculated. Results: A total of 101 cases of off-label rituximab use were analyzed. The median age of the patients involved was 53 [interquartile range (IQR) 37.568.0] years; 55.4 % were women. The indications for prescribing rituximab were primarily hematological diseases (46 %), systemic connective tissue disorders (27 %), and kidney diseases (20 %). Available evidence supporting rituximab treatment for these indications mainly came from individual cohort studies (53.5 % of cases) and case series (25.7 %). The short-term outcome (median 3 months, IQR 24 months) was a complete response in 38 % of cases and partial response in 32.6 %. The highest short-term responses were observed for systemic lupus erythematosus and membranous glomerulonephritis, and the lowest was for neuromyelitis optica, idiopathic thrombocytopenic purpura, and miscellaneous indications. Some response was maintained in long-term follow-up (median 23 months IQR 1230months) in 69.2%of patients showing a short-term response. Median cost per patient was 5,187.5 (IQR 5,187.57,781.3). Conclusions: In our study, off-label rituximab was mainly used for the treatment of hematological, kidney, and systemic connective tissue disorders, and the response among our patient cohort was variable depending on the specific disease. The level of evidence supporting the use of rituximab for these indications was low and the cost was very high. We conclude that more clinical trials on the off-label use of rituximab are needed, although these may be difficult to conduct in some rare diseases. Data from observational studies may provide useful information to assist prescribing in clinical practice.
Resumo:
Langattoman laajakaistaisen tietoliikennetekniikan kehittyminen on herättänyt kiinnostuksen sen ammattimaiseen hyödyntämiseen yleisen turvallisuuden ja kriisinhallinnan tarpeisiin. Hätätilanteissa usein olemassa olevat kiinteät tietoliikennejärjestelmät eivät ole ollenkaan käytettävissä tai niiden tarjoama kapasiteetti ei ole riittävä. Tästä syystä on noussut esiin tarve nopeasti toimintakuntoon saatettaville ja itsenäisille langattomille laajakaistaisille järjestelmille. Tässä diplomityössä on tarkoitus tutkia langattomia ad hoc monihyppy -verkkoja yleisen turvallisuuden tarpeiden pohjalta ja toteuttaa testialusta, jolla voidaan demonstroida sekä tutkia tällaisen järjestelmän toimintaa käytännössä. Työssä tutkitaan pisteestä pisteeseen sekä erityisesti pisteestä moneen pisteeseen suoritettavaa tietoliikennettä. Mittausten kohteena on testialustan tiedonsiirtonopeus, lähetysteho ja vastaanottimen herkkyys. Näitä tuloksia käytetään simulaattorin parametreina, jotta simulaattorin tulokset olisivat mahdollisimman aidot ja yhdenmukaiset testialustan kanssa. Sen jälkeen valitaan valikoima yleisen turvallisuuden vaatimusten mukaisia ohjelmia ja sovellusmalleja, joiden suorituskyky mitataan erilaisten reititysmenetelmien alaisena sekä testialustalla että simulaattorilla. Tuloksia arvioidaan ja vertaillaan. Multicast monihyppy -video päätettiin sovelluksista valita tutkimusten pääkohteeksi ja sitä sekä sen ominaisuuksia on tarkoitus myös oikeissa kenttäkokeissa.
Resumo:
Korkeasaatavuus on olennainen osa nykyaikaisissa, integroiduissa yritysjärjestelmissä. Yritysten kansainvälistyessä tiedon on oltava saatavissa ympärivuorokautisesti, mikä asettaa yhä kovempia vaatimuksia järjestelmän yksittäisten osien saatavuudelle. Kasvava tietojärjestelmäintegraatio puolestaan tekee järjestelmän solmukohdista kriittisiä liiketoiminnan kannalta. Tässä työssä perehdytään hajautettujen järjestelmien ominaisuuksiin ja niiden asettamiin haasteisiin. Esiteltyjä teknologioita ovat muun muassa väliohjelmistot, klusterit ja kuormantasaus. Yrityssovellusten pohjana käytetty Java 2 Enterprise Edition (J2EE) -teknologia käsitellään olennaisilta osiltaan. Työssä käytetään sovelluspalvelinalustana BEA WebLogic Server -ohjelmistoa, jonka ominaisuudet käydään läpi hajautuksen kannalta. Työn käytännön osuudessa toteutetaan kahdelle erilaiselle olemassa olevalle yrityssovellukselle korkean saatavuuden sovelluspalvelinympäristö, joissa sovellusten asettamat rajoitukset on otettu huomioon.
Resumo:
Diagnosis and treatment of arterial hypertension are essential in order to reduce the mortality and the morbidity associated with this condition. The decision to treat hypertension is often based on serial office blood pressure measurements, but new non-invasive measurements such as pulse wave velocity or central blood pressure measurement using pulse wave analysis can be useful to assess the cardiovascular risk with more precision. Indeed, pulse vawe velocity, which is a marker of arterial stiffness, is an independent risk factor for future cardiovascular events. Non-pharmacological and pharmacological therapies can affect both pulse wave velocity and central pressure. However, more studies are needed in order to determine if these measurements can be use as surrogate marker of cardiovascular disease.
Resumo:
De tout temps, hommes et femmes ont cherché par tous les moyens à développer, préserver ou recouvrer leurs propres capacités sexuelles mais également à stimuler le désir du partenaire. L?utilisation d?aphrodisiaques naturels a été l?un des recours les plus répandus. De nos jours, la commercialisation de nouvelles "love drugs" de synthèse, e.g. Viagra®, Cialis®, Levitra®, a remis au goût du jour les aphrodisiaques classiques et à relancer la recherche sur des molécules nouvelles. La pratique croissante de l?automédication, le matraquage publicitaire sur les aphrodisiaques naturels, la prolifération sur le marché de compléments alimentaires non contrôlés et l?absence de véritable législation accroissent les risques qui pèsent sur la santé publique. Dans le but d?évaluer les risques potentiels sur le consommateur de produits aphrodisiaques commercialisés, le développement et la validation d?une méthode rapide d?analyse qualitative et quantitative de la yohimbine dans ces préparations du marché sont exposés dans la première partie de ce travail. La yohimbine est un antagoniste ?2-adrénocepteur du système nerveux central et périphérique, elle est employée depuis plus d?un siècle dans le traitement des dysfonctionnements érectiles. Cette méthode analytique utilise la chromatographie liquide couplée à l?ultraviolet et à la spectrométrie de masse (LC-UV-MS) et au total, vingt préparations aphrodisiaques ont été étudiées. La dose journalière de yohimbine mesurée s?est révélée très variable selon les produits puisqu?elle varie de 1.32 à 23.16 mg. La seconde partie de ce travail concerne l?étude phytochimique et pharmacologique d?Erythroxylum vacciniifolium Mart. (Erythroxylaceae), une plante, appelée localement catuaba, utilisée dans la médecine traditionnelle brésilienne comme tonique et aphrodisiaque. Dans un premier temps, l?extrait alcaloïdique a été analysé par chromatographie liquide haute performance (HPLC) couplée soit à un détecteur UV à barrette d?iode (LC-UV-DAD), soit à un spectromètre de masse (LC-MS), ou soit à un spectromètre de résonance magnétique nucléaire (LC-RMN). L?interprétation de ces données spectrales enregistrées en ligne a permis d?obtenir des informations structurales et d?identifier partiellement près de 24 alcaloïdes appartenant à la classe des tropanes et potentiellement originaux. Par des méthodes classiques de chromatographie liquide sur l?extrait alcaloïdique de la plante, dix sept tropanes nouveaux ont ensuite été isolés dont les catuabines et leurs dérivés, et les vaccinines. Tous ces composés sont des tropane-diols ou triols estérifiés par au moins un groupe acide 1-méthyl-1H-pyrrole-2-carboxylique. Un de ces composés a été identifié comme un tropane N-oxyde. Toutes les structures ont été déterminées par spectrométrie de masse haute résolution et spectroscopie RMN multi-dimensionnelle. Parmi les nombreux tests biologiques réalisés sur ces tropanes, seuls les tests de cytotoxicité se sont révélés faiblement positifs pour certains de ces composés.<br/><br/>Throughout the ages, men and women have incessantly pursued every means to increase, preserve or recapture their sexual capacity, or to stimulate the sexual desire of selected individuals. One of the most recurrent methods has been the use of natural aphrodisiacs. Nowadays, the commercialization of new synthetic "love drugs", e.g. Viagra®, Cialis® and Levitra®, has fascinated the public interest and has led to a reassessment of classical aphrodisiacs and to the search for new ones. The practice of self-medication by an increasing number of patients, the incessant aggressive advertising of these herbal aphrodisiacs, the invasion of the medicinal market with uncontrolled dietary supplements and the absence of real directives amplifies the potential health hazards to the community. In order to evaluate the possible risks of commercialized aphrodisiac products on consumer health, the development and validation of a rapid qualitative and quantitative method for the analysis of yohimbine in these products, is reported in the first part of the present work. Yohimbine, a pharmacologically well-characterized ?2-adrenoceptor antagonist with activity in the central and peripheral nervous system, has been used for over a century in the treatment of erectile dysfunction. The analytical method is based on liquid chromatography coupled with ultraviolet and mass spectrometry (LC-UV-MS) and in total, 20 commercially-available aphrodisiac preparations were analyzed. The amount of yohimbine measured and expressed as the maximal dose per day suggested on product labels ranged from 1.32 to 23.16 mg. The second part of this work involved the phytochemical and pharmacological investigation of Erythroxylum vacciniifolium Mart. (Erythroxylaceae), a plant used in Brazilian traditional medicine as an aphrodisiac and tonic, and locally known as catuaba. With the aim of obtaining preliminary structure information on-line, the alkaloid extract was analyzed by high performance liquid chromatography (HPLC) coupled to diode array UV detection (LC-UVDAD), to mass spectrometry (LC-MS) and to nuclear magnetic resonance spectroscopy (LCNMR). Interpretation of on-line spectroscopic data led to structure elucidation and partial identification of 24 potentially original alkaloids bearing the same tropane skeleton. Seventeen new tropane alkaloids were then isolated from the alkaloid extract of the plant, including catuabines D to I, their derivatives and vaccinines A and B. All compounds were elucidated as tropane-diol or -triol alkaloids esterified by at least one 1-methyl-1H-pyrrole-2-carboxylic acid. One of the isolated compounds was identified as a tropane alkaloid N-oxide. Their structures were determined by high resolution mass spectrometry and multi-dimensional NMR spectroscopy. Among the numerous bioassays undertaken, only the cytotoxicity tests exhibited a weak positive activity of certain compounds.
Resumo:
Purpose: To analyze the therapeutic indications for off-label use of rituximab, the available evidence for its use, the outcomes, and the cost. Methods: This was a retrospective analysis of patients treated with rituximab for off-label indications from January 2007 to December 2009 in two tertiary hospitals. Information on patient characteristics, medical conditions, and therapeutic responses was collected from medical records. Available evidence for the efficacy of rituximab in each condition was reviewed, and the cost of treatment was calculated. Results: A total of 101 cases of off-label rituximab use were analyzed. The median age of the patients involved was 53 [interquartile range (IQR) 37.5-68.0] years; 55.4 % were women. The indications for prescribing rituximab were primarily hematological diseases (46 %), systemic connective tissue disorders (27 %), and kidney diseases (20 %). Available evidence supporting rituximab treatment for these indications mainly came from individual cohort studies (53.5 % of cases) and case series (25.7 %). The short-term outcome (median 3 months, IQR 2-4 months) was a complete response in 38 % of cases and partial response in 32.6 %. The highest short-term responses were observed for systemic lupus erythematosus and membranous glomerulonephritis, and the lowest was for neuromyelitis optica, idiopathic thrombocytopenic purpura, and miscellaneous indications. Some response was maintained in long-term follow-up (median 23 months IQR 12-30months) in 69.2%of patients showing a short-term response. Median cost per patient was 5,187.5 (IQR 5,187.5-7,781.3). Conclusions: In our study, off-label rituximab was mainly used for the treatment of hematological, kidney, and systemic connective tissue disorders, and the response among our patient cohort was variable depending on the specific disease. The level of evidence supporting the use of rituximab for these indications was low and the cost was very high. We conclude that more clinical trials on the off-label use of rituximab are needed, although these may be difficult to conduct in some rare diseases. Data from observational studies may provide useful information to assist prescribing in clinical practice.
Resumo:
Substantial collective flow is observed in collisions between lead nuclei at Large Hadron Collider (LHC) as evidenced by the azimuthal correlations in the transverse momentum distributions of the produced particles. Our calculations indicate that the global v1-flow, which at RHIC peaked at negative rapidities (named third flow component or antiflow), now at LHC is going to turn toward forward rapidities (to the same side and direction as the projectile residue). Potentially this can provide a sensitive barometer to estimate the pressure and transport properties of the quark-gluon plasma. Our calculations also take into account the initial state center-of-mass rapidity fluctuations, and demonstrate that these are crucial for v1 simulations. In order to better study the transverse momentum flow dependence we suggest a new"symmetrized" vS1(pt) function, and we also propose a new method to disentangle global v1 flow from the contribution generated by the random fluctuations in the initial state. This will enhance the possibilities of studying the collective Global v1 flow both at the STAR Beam Energy Scan program and at LHC.