1,558 research outputs found

    Mutual information rate and bounds for it

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    The amount of information exchanged per unit of time between two nodes in a dynamical network or between two data sets is a powerful concept for analysing complex systems. This quantity, known as the mutual information rate (MIR), is calculated from the mutual information, which is rigorously defined only for random systems. Moreover, the definition of mutual information is based on probabilities of significant events. This work offers a simple alternative way to calculate the MIR in dynamical (deterministic) networks or between two data sets (not fully deterministic), and to calculate its upper and lower bounds without having to calculate probabilities, but rather in terms of well known and well defined quantities in dynamical systems. As possible applications of our bounds, we study the relationship between synchronisation and the exchange of information in a system of two coupled maps and in experimental networks of coupled oscillators

    Impact of antibiotic therapy in severe community-acquired pneumonia: Data from the Infauci study

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    Antibiotic therapy (AT) is the cornerstone of the management of severe community-acquired pneumonia (CAP). However, the best treatment strategy is far from being established. To evaluate the impact of different aspects of AT on the outcome of critically ill patients with CAP, we performed a post hoc analysis of all CAP patients enrolled in a prospective, observational, multicentre study. Of the 502 patients included, 76% received combination therapy, mainly a β-lactam with a macrolide (80%). AT was inappropriate in 16% of all microbiologically documented CAP (n=177). Hospital and 6months mortality were 34% and 35%. In adjusted multivariate logistic regression analysis, combination AT with a macrolide was independently associated with a reduction in hospital (OR 0.17, 95%CI 0.06-0.51) and 6months (OR 0.21, 95%CI 0.07-0.57) mortality. Prolonged AT (>7days) was associated with a longer ICU (14 vs. 7days; p7days had no survival benefit and was associated with a longer LOS.info:eu-repo/semantics/publishedVersio

    The INFAUCI study

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    Funding Information: Financial support: this work was supported by an unrestricted grant from GIS (Grupo de Infecção e Sepsis, Hospital de São João, Porto, Portugal). Publisher Copyright: © 2014 European Society of Clinical Microbiology and Infectious Diseases2012 December 2014 10.1111/1469-0691.12738 Original Article INFECTIOUS DISEASES Original Articles © 2014 The Authors Clinical Microbiology and Infection © 2014 European Society of Clinical Microbiology and Infectious Diseases.A prospective, cohort, clinical, observational study was performed in 14 Intensive Care Units (ICUs) to evaluate the contemporary epidemiology, morbi-mortality and determinants of outcome of the population with an infection on admission. All 3766 patients admitted during a consecutive 12-month period were screened. Their median age was 63 [26-83], 61.1% were male and 69.8% had significant comorbidities. On admission to the ICU 1652 patients (43.9%) had an infection, which was community acquired in 68.2% (one-fifth with healthcare-associated criteria) and ward-acquired in the others. Roughly half presented to the ICU with septic shock. As much as 488 patients with community-acquired infections were deemed stable enough to be first admitted to the ward, but had similar mortality to unstable patients directly admitted to the ICU (35.9% vs. 35.1%, p 0.78). Only 48.3% of this infected population had microbiological documentation and almost one-quarter received inappropriate initial antibiotic therapy. This, along with comorbidities, was a main determinant of mortality. Overall, infected patients on admission had higher mortality both in the ICU (28.0% vs. 19.9%, p <0.001) and in the hospital (38.2% vs. 27.5%, p <0.001) and even after being discharged to the ward (14.2% vs. 9.6%, p <0.001). Also, patients not infected on admission who acquired an infection in the ICU, had an increased risk of dying in the hospital (odds ratio 1.41 [1.12-1.83]). Consequently, infection, regardless of its place of acquisition, was associated with increased mortality. Improving the process of care, especially first-line antibiotic appropriateness, and preventing ICU-acquired infections, may lead to better outcomes.publishersversionpublishe

    ACTH-dependent Cushing's syndrome: a revision of 43 cases

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    AIM: To evaluate the characteristics and outcomes of the patients diagnosed as ACTH-dependent Cushing syndrome, registered in the department. MATERIAL AND METHODS: We reviewed the files of forty-three patients followed from 1974 to 2002. RESULTS: A progressive rise in the number of patients diagnosed was found, being 80% females. Clinical suspicion was based mostly on the typical fat distribution; hirsutism and amenorrhoea were important in women. The more reliable diagnostic tests were: 11 pm cortisol, day curve of ACTH and cortisol, and dexamethasone suppression tests. The ACTH response to CRH during inferior petrosal sinus sampling permitted the diagnosis of ectopic source. In thirty-seven patients a pituitary adenoma was diagnosed. The three patients diagnosed before 1985 went for bilateral adrenalectomy (Nelson's syndrome in two); the others were submitted to transsphenoidal pituitary adenomectomy, obtaining remission in twenty six at the first operation and in two others at the second. Three patients had a recidive. Of the six patients with persistent disease (all treated with metyrapone or ketoconazole), three were submitted to radiotherapy, two to bilateral adrenalectomy, and one was waiting for surgery. Four patients had a bronchial carcinoid, successfully removed in three. One patient was lost to follow-up and another was still being evaluated. CONCLUSIONS: We found a positive evolution in the capacity to diagnose and treat these patients. Neurosurgical ability to achieve remission was 80% in the operated cases. More effective technical methods and drugs, as well as a multidisciplinary and dedicated medical team, lead to long lasting remissions in most of the patients

    HST/FOS Eclipse Observations of the Nova-like Cataclysmic Variable UX Ursae Majoris

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    [abridged abstract] We present and analyze Hubble Space Telescope observations of the eclipsing nova-like cataclysmic variable UX UMa obtained with the Faint Object Spectrograph. Two eclipses each were observed with the G160L grating (covering the ultraviolet waveband) in August of 1994 and with the PRISM (covering the near-ultraviolet to near-infrared) in November of the same year. The system was 50% brighter in November than in August, which, if due to a change in the accretion rate, indicates a fairly substantial increase in Mdot_acc by >~ 50%. Model disk spectra constructed as ensembles of stellar atmospheres provide poor descriptions of the observed post-eclipse spectra, despite the fact that UX UMa's light should be dominated by the disk at this time. Suitably scaled single temperature model stellar atmospheres with T_eff = 12,500-14,500 K actually provide a better match to both the ultraviolet and optical post-eclipse spectra. Evidently, great care must be taken in attempts to derive accretion rates from comparisons of disk models to observations. One way to reconcile disk models with the observed post-eclipse spectra is to postulate the presence of a significant amount of optically thin material in the system. Such an optically thin component might be associated with the transition region (``chromosphere'') between the disk photosphere and the fast wind from the system, whose presence has been suggested by Knigge & Drew (1997).Comment: 35 pages, including 12 figures; to appear in the ApJ (Vol. 499

    Collateral pial circulation relates to the degree of brain edema on CT 24 hours after ischemic stroke

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    Background Cerebral edema is frequent in patients with acute ischemic stroke (AIS) who undergo reperfusion therapy and is associated with high mortality. The impact of collateral pial circulation (CPC) status on the development of edema has not yet been determined. Methods We studied consecutive patients with AIS and documented M1-middle cerebral artery (MCA) and/or distal internal carotid artery (ICA) occlusion who underwent reperfusion treatment. Edema was graded on the 24-hour non-contrast computed tomography (NCCT) scan. CPC was evaluated at the acute phase (≤6 hours) by transcranial color-coded Doppler, angiography and/or CT angiography. We performed an ordinal regression model for the effect of CPC on cerebral edema, adjusting for age, baseline National Institutes of Health Stroke Scale, Alberta Stroke Program Early Computed Tomography Score (ASPECTS) on admission, NCCT, parenchymal hemorrhagic transformation at 24 hours and complete recanalization at six hours. Results Among the 108 patients included, 49.1% were male and mean age was 74.2 ± 11.6 years. Multivariable analysis showed a significant association between cerebral edema and CPC status (OR 0.22, 95% CI 0.08-0.59, p = 0.003), initial ASPECTS (OR 0.72, 95% CI 0.57-0.92, p = 0.007) and parenchymal hemorrhagic transformation (OR 23.67, 95% CI 4.56-122.8, p < 0.001). Conclusions Poor CPC is independently associated with greater cerebral edema 24 hours after AIS in patients who undergo reperfusion treatment.info:eu-repo/semantics/publishedVersio

    Search for bioindicators of pollution in the Guanabara Bay: integrations of ecologic patterns

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    Guanabara Bay, since its discovery, has largely changed with the human occupation causing large amounts of deposited sediment and waste, as well as domestic and industry sewage. Surface sediment was analysed for foraminifera and ostracoda distribution, diversity and dominance studies. These results were compared with TOC analyses aiming the determination of pollution bioindicators. In general, foraminifera dominant species were Ammonia tepida, Buliminella elegantissima and Quinqueloculina seminulum. The foraminifera assemblages presented distinct abundance and diversity values in different regions of the bay. The diversity was higher in the entrance (south) and in the central region than in the north region of the bay. The dominant species, that are characteristic of stressed environments, presented higher values of abundance in the north region. The TOC values increased from south to north regions, and were inversely proportional to foraminifera diversity. The very high TOC values in very polluted areas suggest sediment deposition in anoxic-dysoxic environment. The ostracoda Gen. Cyprideis was dominant and its occurrence increased from south to north region. Occurrence of Callistocythere sigmocostata, Xestoleberis sp., Aurila sp., and Paracypris sp. were restricted to the entrance and central area, indicating a preference for less restricted conditions, like marine conditions. Foraminifera and ostracoda characteristic responses to the environment conditions related high TOC values showed their importance as bioindicators of stressed environments caused by anthropogenic pollution, in the Guanabara Bay.A Baía de Guanabara, desde o seu descobrimento, tem sido bastante modificada pela ocupação humana, causando o acúmulo de grande quantidade de sedimento depositado e lixo, bem como lançamento de esgotos domésticos e industriais. Sedimentos superficiais foram analisados visando o estudo da distribuição, diversidade e dominância de foraminíferos e ostracodes. Estes estudos foram comparados com análises de COT objetivando a determinação de bioindicadores de poluição. Em geral as espécies dominantes de foraminíferos foram Ammonia tepida,Buliminella elegantissima and Quinqueloculina seminulum. As associações de foraminíferos apresentam distintos valores de abundância e diversidade em diferentes regiões da Baía. A diversidade foi mais elevada na entrada (sul) e na região central do que na região norte da Baía. As espécies dominantes, que são características de ambientes sob estresse, apresentaram valores altos de abundância na região norte. Os valores de COT aumentaram da região sul para o norte e foram inversamente proporcionais à diversidade de foraminíferos. O elevados valores de COT em áreas muito poluídas sugerem deposição sedimentar em ambiente anóxico-desóxico. O Gen. Cyprideis, de ostracode, foi dominante e sua ocorrência aumentou da região sul para o norte. A ocorrência de Callistocythere sigmocostata, Xestoleberis sp., Aurila sp. e Paracypris sp. foi estrita à entrada e região central, indicando uma preferência por condições menos restritas, como condições marinhas. As respostas características dos foraminíferos e ostracodes às condições ambientais relacionadas aos elevados valores de COT mostraram sua importância como bioindicadores de ambientes sob estresse causado por poluição antropogênica na Baía de Guanabara

    A rede carioca de agricultura urbana e o direito à cidade.

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    presente artigo visa analisar a noção de direito à cidade do filósofo francês Henri Lefebre, à luz da realidade do Rio de Janeiro, uma cidade latino-americana. Compreende-se que a obra de Lefebvre deve estar coadunada com uma revisão bibliográfica histórica acerca das requalificações e remoções da cidade do Rio de Janeiro. Nesse sentido, é necessário analisar as novas áreas de centralidade e conflitos. E a atuação da Rede Carioca de Agricultura Urbana (Rede CAU) torna-se emblemática nessa perspectiva. Nos anos 2000, com o aumento da produção imobiliária na Zona Oeste do Rio de Janeiro, principalmente, para a Área de Planejamento (AP) 4, bairros com histórico de atividade agrícola tornam-se alvo. Dentre eles, encontra-se a região das Vargens, compreendida pelos bairros de Vargem Grande, Vargem Pequena, Camorim e parte dos bairros do Recreio dos Bandeirantes, Barra da Tijuca e Jacarepaguá. Cabe destacar a atuação do Planejamento Urbano por parte do Estado com os instrumentos urbanísticos para a viabilização dessa expansão imobiliária, como o Plano de Estruturação Urbana (PEU) das Vargens e a Lei de Uso e Ocupação do Solo (LUOS) que diminui as áreas agrícolas da região. Nesse contexto, apesar de negligenciada dos debates acerca das lutas urbanas, que geralmente dicotomiza a agricultura da cidade, a Rede CAU, a partir da Agroecologia, apropria-se da luta pelo Direito à cidade e do Planejamento Urbano através da Articulação Plano Popular das Vargens (APP Vargens), ressignificando o direito à cidade, pautando que ela também é o direito de plantarTítulo em Espanhol: La red carioca de agrigultura urbana y el derecho a la ciuda

    Influence of cold thermal environment on core temperature, blood pressure and heart rate

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    Severe cold exposure is a significant risk factor in the frozen food industry, influencing the health and safety of employees. The objective of this work is to verify the influence of the severe cold exposure, using personal protective equipment similar to those used in industry,on physiological parameters such as blood pressure, heart rate and core temperature. Twelve non-acclimatized male volunteers (mean +/- SD) were selected: age 24 +/- 3.09 years and exposed for 60 minutes in a climatic chamber at -20 degrees C with protective clothing. During the exhibition, they simulated activities usually developed in the frozen industry such as ordering boxes on shelves. Core temperature was recorded through intra-abdominal temperature using an Equivital Ingestible Tablet Sensor (telemetry thermometer). The results showed increases in systolic blood pressure and heart rate, moments after the end of severe cold exposure. On the other hand, diastolic blood pressure showed on average a decrease 6 mmHg. Core temperature, despite a decrease in the initial minutes of exposure, increased by an average of 0.28 degrees C by the end of the trial. It was concluded that clothing and physical activity increase core temperature even in extreme cold situations. Therefore, consideration of these parameters should be the starting point for an adequate evaluation and management of risks of work in these circumstances
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