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We present a multi-modal genre recognition framework that considers the modalities audio, text, and image by features extracted from audio signals, album cover images, and lyrics of music tracks. In contrast to pure learning of features by a neural network as done in the related work, handcrafted features designed for a respective modality are also integrated, allowing for higher interpretability of created models and further theoretical analysis of the impact of individual features on genre prediction. Genre recognition is performed by binary classification of a music track with respect to each genre based on combinations of elementary features. For feature combination a two-level technique is used, which combines aggregation into fixed-length feature vectors with confidence-based fusion of classification results. Extensive experiments have been conducted for three classifier models (Naïve Bayes, Support Vector Machine, and Random Forest) and numerous feature combinations. The results are presented visually, with data reduction for improved perceptibility achieved by multi-objective analysis and restriction to non-dominated data. Feature- and classifier-related hypotheses are formulated based on the data, and their statistical significance is formally analyzed. The statistical analysis shows that the combination of two modalities almost always leads to a significant increase of performance and the combination of three modalities in several cases.
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While right heart catheterization (RHC) at rest is the gold standard to assess pulmonary hemodynamics in patients with chronic obstructive pulmonary disease (COPD) and pulmonary hypertension (PH), the invasive measurement of exercise hemodynamics is less well established in this group. Since exercise hemodynamics are increasingly recognized as important clinical information in patients with PH, our goal was to review the literature in this field to provide a basis for clinical use, further studies, and future recommendations. We identified 69 studies (published since 1968) reporting RHC data in 2819 patients with COPD, of whom 2561 underwent exercise testing. Few studies simultaneously measured gas exchange during exercise. Overall, these studies showed large variations in the patient populations and research questions studied and the methods and definitions employed. Despite these limitations, the data consistently demonstrated the presence of precapillary PH at rest in up to 38% of patients with COPD. With exercise, a relevant proportion of patients developed an abnormal hemodynamic response, depending on the definition used. Furthermore, some studies assessed right ventricular function during exercise and showed a blunted increase in right ventricular ejection fraction. Drug effects and the impact of interventional procedures were also studied. Again, due to large variations in the patients studied and the methods used, firm conclusions are difficult to derive. Despite the limitations of this dataset, several recommendations with respect to technical aspects (body position, exercise protocol, and data acquisition) can be inferred for this challenging patient population and may be helpful for further studies or recommendations.
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Cateterismo Cardíaco , Hipertensão Pulmonar/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Cateterismo Cardíaco/métodos , Exercício Físico/fisiologia , Hemodinâmica , Humanos , Hipertensão Pulmonar/etiologia , Oxigenoterapia , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/terapia , Descanso/fisiologia , Vasodilatadores/uso terapêutico , Disfunção Ventricular Direita/etiologia , Disfunção Ventricular Direita/fisiopatologiaRESUMO
The PAMONO-sensor (plasmon assisted microscopy of nano-objects) demonstrated an ability to detect and quantify individual viruses and virus-like particles. However, another group of biological vesicles-microvesicles (100-1000 nm)-also attracts growing interest as biomarkers of different pathologies and needs development of novel techniques for characterization. This work shows the applicability of a PAMONO-sensor for selective detection of microvesicles in aquatic samples. The sensor permits comparison of relative concentrations of microvesicles between samples. We also study a possibility of repeated use of a sensor chip after elution of the microvesicle capturing layer. Moreover, we improve the detection features of the PAMONO-sensor. The detection process utilizes novel machine learning techniques on the sensor image data to estimate particle size distributions of nano-particles in polydisperse samples. Altogether, our ï¬ndings expand analytical features and the application ï¬eld of the PAMONO-sensor. They can also serve for a maturation of diagnostic tools based on the PAMONO-sensor platform.
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The increasing importance of intensive care medicine including mechanical ventilation has been accompanied by the demand of weaning opportunities for patients undergoing prolonged mechanical ventilation. Consequently, specialised clinical institutions, focusing on the weaning from mechanical ventilation, have been established since the 1980âs.The present article illustrates the structural development and results of such a specialised institution at the University Medicine Greifswald, using data of 616 patients collected within the past ten years (2006â-â2015). Across the years, a shift in the underlying disease leading to mechanical ventilation can be found, with rising numbers of patients suffering from pneumonia/sepsis and declining numbers of patients who underwent cardiac surgery in advance. The days with mechanical ventilation outside (pâ=â0.004) and within the investigated institution (pâ=â0.02) are significantly declining. The percentage of successfully weaned patients increased from 62.7â% (2006â-â2010) to 77.3â% (2011â-â2015), pâ<â0.001.âConsecutively, the percentage of patients who remained mechanically ventilated decreased from 16.4â% to 9.6â% (pâ<â0.001) and the share of in-hospital deceased patients significantly declined from 20.9â% to 13.0â% (pâ<â0.001). Furthermore, the one-year-survival after hospital discharge in successful weaned patients was 72 percent. The present data, collected at the University Medicine Greifswald are quite comparable to data of other German institutions that are specialised on weaning from mechanical ventilation.
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Unidades Hospitalares/organização & administração , Hospitais Universitários/organização & administração , Unidades de Terapia Intensiva/organização & administração , Assistência de Longa Duração/organização & administração , Pneumonia/terapia , Sepse/terapia , Desmame do Respirador/métodos , Idoso , Feminino , Alemanha , Unidades Hospitalares/tendências , Hospitais Universitários/tendências , Humanos , Unidades de Terapia Intensiva/tendências , Assistência de Longa Duração/tendências , Masculino , Pessoa de Meia-Idade , Pneumonia/mortalidade , Sepse/mortalidade , Taxa de Sobrevida/tendências , Desmame do Respirador/tendênciasRESUMO
Recent proof-of-principle studies demonstrated the suitability of the surface plasmon resonance imaging (SPRi) technique for the detection of individual submicrometer and nanoparticles in solutions. In the current study, we used the SPRi technique for visualization of the binding of round-shaped viruses (inactivated influenza A virus) and virus-like particles (human immunodeficiency virus (HIV)-based virus-like particles) to the functionalized sensor surface. We show the applicability of the SPRi technique for the detection of individual virus-like particles in buffers without serum as well as in buffers containing different concentrations of serum. Furthermore, we prove the specificity of visualized binding events using two different pseudotypes of HIV virus-like particles. We also demonstrate the applicability of the SPRi technique for the determination of relative particle concentrations in solutions. Moreover, we suggest a technical approach, which allows enhancing the magnitude of binding signals. Our studies indicate that the SPRi technique represents an efficient research tool for quantification and characterization of biological submicrometer objects such as viruses or virus-like particles, for example.
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Vírus da Influenza A/metabolismo , Tamanho da Partícula , Ressonância de Plasmônio de Superfície/métodos , Vírus do Mosaico do Tabaco/metabolismo , Vírion/metabolismo , Células HEK293 , HIV/química , Humanos , Vírus do Mosaico do Tabaco/química , Vírion/química , Água/químicaRESUMO
PURPOSE: Weaning from mechanical ventilation is a key component of intensive care treatment; however, this process may be prolonged as some patients require care at specialised centres. Current data indicate that weaning from invasive mechanical ventilation is successful in approximately 65% of patients; however, data on long-term survival after discharge from a weaning centre are limited. MATERIALS AND METHODS: We analysed predictors of survival among 597 patients (392 men, mean age 68 ± 11) post-discharge from a specialised German weaning centre. RESULTS: Complete weaning from mechanical ventilation was achieved in 407 (57.8%) patients, and 106 patients (15.1%) were discharged with non-invasive ventilation; thus, prolonged weaning was successful in 72.9% of the patients. The one-year and five-year survival rates post-discharge were 66.5% and 37.1%, respectively. Age, duration of mechanical ventilation, certain clusters of comorbidities, and discharged with mechanical ventilation significantly influenced survival (p < .001). Completely weaned patients who were discharged with a tracheostomy had a significantly reduced survival rate than did those who were completely weaned and discharged with a closed tracheostomy (p = .004). CONCLUSIONS: The identified predictors of survival after prolonged weaning could support therapeutic strategies during patients' intensive care unit stay. Patients should be closely monitored after discharge from a weaning centre.
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Assistência ao Convalescente/métodos , Cuidados Críticos/métodos , Tempo de Internação , Ventilação não Invasiva/mortalidade , Desmame do Respirador/mortalidade , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Feminino , Febre , Seguimentos , Humanos , Unidades de Terapia Intensiva , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Ventilação não Invasiva/métodos , Alta do Paciente , Taxa de Sobrevida , Traqueostomia , Desmame do Respirador/métodosRESUMO
This prospective study compared exercise test and intravenous fluid challenge in a single right heart catheter procedure to detect latent diastolic heart failure in patients with echocardiographic heart failure with preserved ejection function. We included 49 patients (73% female) with heart failure with preserved ejection function and pulmonary artery wedge pressure ≤15 mmHg. A subgroup of 26 patients had precapillary pulmonary hypertension. Invasive haemodynamic and gas exchange parameters were measured at rest, 45° upright position, during exercise, after complete haemodynamic and respiratory recovery in lying position, and after rapid infusion of 500 mL isotonic solution. Most haemodynamic parameters increased at both exercise and intravenous fluid challenge, with the higher increase at exercise. Pulmonary vascular resistance decreased by -0.21 wood units at exercise and -0.56 wood units at intravenous fluid challenge (p = 0.3); 20% (10 of 49) of patients had an increase in pulmonary artery wedge pressure above the upper limit of 20 mmHg at exercise, and 20% above the respective limit of 18 mmHg after intravenous fluid challenge. However, only three patients exceeded the upper limit of pulmonary artery wedge pressure in both tests, i.e. seven patients only at exercise and seven other patients only after intravenous fluid challenge. In the subgroup of pulmonary hypertension patients, only two patients exceeded pulmonary artery wedge pressure limits in both tests, further five patients at exercise and four patients after intravenous fluid challenge. A sequential protocol in the same patient showed a significantly higher increase in haemodynamic parameters at exercise compared to intravenous fluid challenge. Both methods can unmask diastolic dysfunction at right heart catheter procedure, but in different patient groups.
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The question of when modern birds (Neornithes) first diversified has generated much debate among avian systematists. Fossil evidence generally supports a Tertiary diversification, whereas estimates based on molecular dating favor an earlier diversification in the Cretaceous period. In this study, we used an alternate approach, the inference of historical biogeographic patterns, to test the hypothesis that the initial radiation of the Order Psittaciformes (the parrots and cockatoos) originated on the Gondwana supercontinent during the Cretaceous. We utilized broad taxonomic sampling (representatives of 69 of the 82 extant genera and 8 outgroup taxa) and multilocus molecular character sampling (3,941 bp from mitochondrial DNA (mtDNA) genes cytochrome oxidase I and NADH dehydrogenase 2 and nuclear introns of rhodopsin intron 1, tropomyosin alpha-subunit intron 5, and transforming growth factor ss-2) to generate phylogenetic hypotheses for the Psittaciformes. Analyses of the combined character partitions using maximum parsimony, maximum likelihood, and Bayesian criteria produced well-resolved and topologically similar trees in which the New Zealand taxa Strigops and Nestor (Psittacidae) were sister to all other psittaciforms and the cockatoo clade (Cacatuidae) was sister to a clade containing all remaining parrots (Psittacidae). Within this large clade of Psittacidae, some traditionally recognized tribes and subfamilies were monophyletic (e.g., Arini, Psittacini, and Loriinae), whereas several others were polyphyletic (e.g., Cyclopsittacini, Platycercini, Psittaculini, and Psittacinae). Ancestral area reconstructions using our Bayesian phylogenetic hypothesis and current distributions of genera supported the hypothesis of an Australasian origin for the Psittaciformes. Separate analyses of the timing of parrot diversification constructed with both Bayesian relaxed-clock and penalized likelihood approaches showed better agreement between geologic and diversification events in the chronograms based on a Cretaceous dating of the basal split within parrots than the chronograms based on a Tertiary dating of this split, although these data are more equivocal. Taken together, our results support a Cretaceous origin of Psittaciformes in Gondwana after the separation of Africa and the India/Madagascar block with subsequent diversification through both vicariance and dispersal. These well-resolved molecular phylogenies will be of value for comparative studies of behavior, ecology, and life history in parrots.
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Psittaciformes/genética , Animais , Teorema de Bayes , Evolução Biológica , Primers do DNA/química , DNA Mitocondrial/genética , Ecologia , Evolução Molecular , Fósseis , Especiação Genética , Variação Genética , Modelos Genéticos , Filogenia , Fatores de TempoRESUMO
Intravascular brachytherapy (IVB) can significantly reduce the risk of restenosis after interventional treatment of stenotic arteries, if planned and applied correctly. To facilitate computer-based IVB planning, a three-dimensional vessel model has been derived from information on coronary artery segments acquired by intravascular ultrasound (IVUS) and biplane angiography. Part I describes the approach of model construction and presents possibilities of visualization. The vessel model is represented by a voxel volume. Polygonal information about the vessel wall structure is derived by segmentation from a sequence of IVUS images automatically acquired ECG gated during pull back of the IVUS transducer. To detect horizontal, vertical, and radial contours, modified Canny-Edge and Shen-Castan filters are applied on Cartesian and polar coordinate representations of the IVUS tomograms as edge detectors. The spatial course of the vessel wall layers is traced in reconstructed longitudinal IVUS scans. By resampling the sequence of IVUS frames the voxel volume is obtained. For this purpose the frames are properly located in space and augmented with additional intermediate frames generated by interpolation. Their spatial location and orientation is derived from biplane X-ray angiography which is performed simultaneously. For resampling, two approaches are proposed: insertion of the vertices of the rectangular goal grid into the cells of a deformed hexahedral mesh derived from the IVUS sequence, and insertion of the vertices of the hexahedral mesh into the cells of the rectangular grid. Finally, the vessel model is visualized by methods of combined volume and polygon rendering. The segmentation process is verified as being in good agreement with results obtained by manual contour tracing with a commercial system. Our approach of construction of the vessel model has been implemented into an interactive software system, 3D IVUS-View, serving as the basis of a future system for intracoronary brachytherapy treatment planning being currently under development (Part II).
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Algoritmos , Artérias/diagnóstico por imagem , Braquiterapia/métodos , Vasos Coronários/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Interface Usuário-Computador , Artérias/efeitos da radiação , Cateterismo/métodos , Simulação por Computador , Vasos Coronários/efeitos da radiação , Meio Ambiente , Feminino , Humanos , Masculino , Modelos Cardiovasculares , Reconhecimento Automatizado de Padrão , Radiometria/métodos , Dosagem Radioterapêutica , Ultrassonografia de Intervenção/métodosRESUMO
In this article, we present a new method for the generation of surface meshes of biological soft tissue. The method is based on the deformable surface model technique and is extended to histological data sets. It relies on an iterative adjustment towards polygonal segments describing the histological structures of the soft tissue. The generated surface meshes allow for the construction of volumetric meshes through a standard constrained Delaunay approach and, thus, for the application in finite element methods. The geometric properties of volumetric meshes have an immediate influence on the numerical conditioning and, therewith, on the stability of the finite element method and the convergence of iterative solvers. In this article, the influence of the surface meshes on the quality of the volumetric meshes is analysed in terms of the spectral condition number of the stiffness matrices, which are assembled within Newton's method. The non-linear material behavior of biological soft tissue is modeled by the Mooney-Rivlin material law. The subject is motivated by the requirements of virtual surgery.