Παρασκευή 12 Μαΐου 2017

Automatic music genre classification based on musical instrument track separation

Abstract

The aim of this article is to investigate whether separating music tracks at the pre-processing phase and extending feature vector by parameters related to the specific musical instruments that are characteristic for the given musical genre allow for efficient automatic musical genre classification in case of database containing thousands of music excerpts and a dozen of genres. Results of extensive experiments show that the approach proposed for music genre classification is promising. Overall, conglomerating parameters derived from both an original audio and a mixture of separated tracks improve classification effectiveness measures, demonstrating that the proposed feature vector and the Support Vector Machine (SVM) with Co-training mechanism are applicable to a large dataset.



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Concentration polarization phenomenon in the case of mechanical pressure difference on the membrane

Abstract

We analyzed the transport of KCl solutions through the bacterial cellulose membrane and concentration boundary layers (CBLs) near membrane with pressure differences on the membrane. The membrane was located in horizontal-plane between two chambers with different KCL solutions. The membrane was located in horizontal-plane between two chambers with different KCL solutions. As results from the elaborated model, gradient of KCL concentration in CBLs is maximal at membrane surfaces in the case when pressure difference on the membrane equals zero. The amplitude of this maximum decreases with time of CBLs buildup. Application of mechanical pressure gradient in the direction of gradient of osmotic pressure on the membrane causes a shift of this maximum into the chamber with lower concentration. In turn, application of mechanical pressure gradient directed opposite to the gradient of osmotic pressure causes the appearance of maximum of concentration gradient in chamber with higher concentration. Besides, the increase of time of CBLs buildup entails a decrease of peak height and shift of this peak further from the membrane. Similar behavior is observed for distribution of energy dissipation in CBLs but for pressure difference on the membrane equal to zero the maximum of energy dissipation is observed in the chamber with lower concentration. We also measured time characteristics of voltage in the membrane system with greater KCl concentrations over the membrane. We can state that mechanical pressure difference on the membrane can suppress or strengthen hydrodynamic instabilities visible as pulsations of measured voltage. Additionally, time of appearance of voltage pulsations, its amplitude, and frequency depend on mechanical pressure differences on the membrane and initial quotient of KCl concentrations in chambers.



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Acquiring research-grade ERPs on a shoestring budget: A comparison of a modified Emotiv and commercial SynAmps EEG system

Abstract

This study compared the performance of a low-cost wireless EEG system to a research-grade EEG system on an auditory oddball task designed to elicit N200 and P300 ERP components. Participants were 15 healthy adults (6 female) aged between 19 and 40 (M = 28.56; SD = 6.38). An auditory oddball task was presented comprising 1,200 presentations of a standard tone interspersed by 300 trials comprising a deviant tone. EEG was simultaneously recorded from a modified Emotiv EPOC and a NeuroScan SynAmps RT EEG system. The modifications made to the Emotiv system included attaching research grade electrodes to the Bluetooth transmitter. Additional modifications enabled the Emotiv system to connect to a portable impedance meter. The cost of these modifications and portable impedance meter approached the purchase value of the Emotiv system. Preliminary analyses revealed significantly more trials were rejected from data acquired by the modified Emotiv compared to the SynAmps system. However, the ERP waveforms captured by the Emotiv system were found to be highly similar to the corresponding waveform from the SynAmps system. The latency and peak amplitude of N200 and P300 components were also found to be similar between systems. Overall, the results indicate that, in the context of an oddball task, the ERP acquired by a low-cost wireless EEG system can be of comparable quality to research-grade EEG acquisition equipment.



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Inducing unconscious stress: Cardiovascular activity in response to subliminal presentation of threatening and neutral words

Abstract

Stress-related cognitive processes may occur outside of awareness, here referred to as unconscious stress, and affect one's physiological state. Evidence supporting this idea would provide necessary clarification of the relationship between psychological stress and cardiovascular (CV) health problems. We tested the hypothesis that increases in mean arterial pressure (MAP) and total peripheral resistance (TPR) and decreases in heart rate variability (HRV) would be larger when threatening stimuli are presented outside of awareness, or subliminally, compared with neutral stimuli. Additionally, it was expected that trait worry and resting HRV, as common risk factors for CV disease, would moderate the effect. We presented a subliminal semantic priming paradigm to college students that were randomly assigned to the threat (n = 56) or neutral condition (n = 60) and assessed changes from baseline of MAP, TPR, and HRV. Level of trait worry was assessed with the Penn State Worry Questionnaire. The findings indicate that CV activity changed according to the hypothesized pattern: A higher MAP and TPR and a lower HRV in the threat condition compared with the neutral condition were found with practically meaningful effect sizes. However, these findings were only statistically significant for TPR. Furthermore, changes in CV activity were not moderated by trait worry or resting HRV. This is the first study to explicitly address the role of subliminally presented threat words on health-relevant outcome measures and suggests that unconscious stress can influence peripheral vascular resistance.



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Characteristics and prognosis of glomangiopericytomas: A systematic review

Abstract

Background

Glomangiopericytoma belongs to the category of borderline/low-malignant-potential tumors of the sinonasal tract, but no studies about prognosis have been reported.

Methods

To define the characteristics of glomangiopericytoma and to identify its prognostic factors, a systematic review was performed. A total of 337 cases of glomangiopericytomas were analyzed.

Results

Patients with glomangiopericytoma demonstrating resection margin involvement and receiving radiotherapy/chemotherapy had a significantly worse disease-free survival time (P =  .014 and .006, respectively). Patients with glomangiopericytoma had a tendency toward longer overall survival when they were diagnosed at a younger age (≤60 years; P = .001), did not demonstrate marginal involvement (P = .032), recurrence/metastasis (P = .002), or radiotherapy/chemotherapy (P = .010), and had a right-sided tumor (P < .001), actin-immunopositivity (P < .001), and CD34-/BCL2-immunonegativities (P = .002 and .019, respectively). By multivariate analysis, actin (P < .001) and CD34 (P = .002) immunostaining were significantly related to the overall survival of patients with glomangiopericytoma.

Conclusion

Actin and CD34 immunostaining could be used as independent prognostic indicators of glomangiopericytomas.



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Office-based procedures for diagnosis and treatment of esophageal pathology

Abstract

Background

Diagnostic and therapeutic office-based procedures under topical anesthesia are emerging in the daily practice of laryngologists and head and neck surgeons. Since the introduction of the transnasal esophagoscope, office-based procedures for the esophagus are increasingly performed.

Methods

We conducted a systematic review of literature on office-based procedures under topical anesthesia for the esophagus.

Results

Transnasal esophagoscopy is an extensively investigated office-based procedure. This procedure shows better patient tolerability and equivalent accuracy compared to conventional transoral esophagoscopy, as well as time and cost savings. Secondary tracheoesophageal puncture, esophageal dilatation, esophageal sphincter injection, and foreign body removal are less investigated, but show promising results.

Discussion

With the introduction of the transnasal esophagoscope, an increasing number of diagnostic and therapeutic office-based procedures for the esophagus are possible, with multiple advantages. Further investigation must prove the clinical feasibility and effectiveness of the therapeutic office-based procedures.



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Viruses, Vol. 9, Pages 107: A Conserved Residue, Tyrosine (Y) 84, in H5N1 Influenza A Virus NS1 Regulates IFN Signaling Responses to Enhance Viral Infection

The non-structural protein, NS1, is a virulence factor encoded by influenza A viruses (IAVs). In this report, we provide evidence that the conserved residue, tyrosine (Y) 84, in a conserved putative SH2-binding domain in A/Duck/Hubei/2004/L-1 [H5N1] NS1 is critical for limiting an interferon (IFN) response to infection. A phenylalanine (F) substitution of this Y84 residue abolishes NS1-mediated downregulation of IFN-inducible STAT phosphorylation, and surface IFNAR1 expression. Recombinant IAV (rIAV) [H1N1] expressing A/Grey Heron/Hong Kong/837/2004 [H5N1] NS1-Y84F (rWSN-GH-NS1-Y84F) replicates to lower titers in human lung epithelial cells and is more susceptible to the antiviral effects of IFN-β treatment compared with rIAV expressing the intact H5N1 NS1 (rWSN-GH-NS1-wt). Cells infected with rWSN-GH-NS1-Y84F express higher levels of IFN stimulated genes (ISGs) associated with an antiviral response compared with cells infected with rWSN-GH-NS1-wt. In mice, intranasal infection with rWSN-GH-NS1-Y84F resulted in a delay in onset of weight loss, reduced lung pathology, lower lung viral titers and higher ISG expression, compared with mice infected with rWSN-GH-NS1-wt. IFN-β treatment of mice infected with rWSN-GH-NS1-Y84F reduced lung viral titers and increased lung ISG expression, but did not alter viral titers and ISG expression in mice infected with rWSN-GH-NS1-wt. Viewed altogether, these data suggest that the virulence associated with this conserved Y84 residue in NS1 is, in part, due to its role in regulating the host IFN response.

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