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Novelty detection is a problem with a large number of relevant applications. For some applications, the main interest is the prevention or detection of undesired states. In some cases, these undesired states are not known in advance; in others, such as machine monitoring, for instance, machine breakdown may be very rare and examples of this event may be unavailable. In such cases, the most widely accepted approach is to model the normal behavior of the system in order to subsequently detect unknown events. This is the basic concept of One-Class Classification (OCC). In some preliminary works we have proposed the Feature Boundaries Detector for One-Class Classification FBDOCC method, which operates by examining each problem feature at a time. In this paper we propose an extensive study of the behavior of the FBDOCC and introduce another version of the method, namely FBDOCC2. This work, also considers the use of the Particle Swarm Optimization (PSO) algorithm to find the best parameter configuration of the proposed method. Furthermore, this work also introduces a procedure to improve the training time performance without degrading the quality of the classification as well as some other contributions hereafter described. A number of experiments were carried out with synthetic and real datasets aiming at comparing both versions of the FBDOCC method with the most recent and effective OCC methods, namely: SVDD, One-class SVM, Least Squares One-class SVM, Kernel PCA, Gaussian Process Prior OCC, Condensed Nearest Neighbor Data Description and One-class Random Forests. The evaluation metrics considered in the experiments are: (i) the Area Under the ROC Curve (AUC); (ii) the Matthews Correlation Coefficient (MCC); (iii) the training time; and (iv) the prototype reduction rate. Regarding the metrics AUC and MCC, the first FBDOCC version has presented the best overall results among all the methods whereas the FBDOCC2 obtained results comparable to the best methods in some experiments where the standard FBDOCC yielded a poorer performance. FBDOCC was the faster method to train in comparison to the other methods in all but one dataset. In addition, FBDOCC was much faster than all methods based on support vector machines. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to investigate acute cardiac response and heart rate variability (HRV) when listening to differing forms of music. Eleven healthy men aged between 18 and 25 years old were included in the study. HRV was recorded at rest for ten minutes with no music, then were asked to listen to classical baroque or heavy metal music for a period of 20 min. It was noted that heart rate variability did not affect HRV indices for time and frequency. In conclusion, music with different tempos does not influence cardiac autonomic regulation in men. However more studies are suggested to explore this topic in greater detail. [Copyright &y& Elsevier]

Abstract: We present in this work a comprehensive investigation of the role played by dissolved tetrafluoroboric acid on the electrochemical response of a polycrystalline platinum electrode in acidic media. HBF4 from two different suppliers was employed and characterized in terms of the amount of arsenic contamination by Inductively Coupled Plasma-Optical Emission Spectroscopy. The effect of different amounts of HBF4 on the voltammetric profile of the Pt|HClO4(aq) interface was investigated by means of electrochemical quartz crystal nanobalance (EQCN). Despite the comparable cyclic voltammograms, the presence of arsenic in one of the two HBF4 used resulted in dramatic variations in the mass change profile, which evidences the deposition/dissolution of arsenic prior to the surface oxidation. For the arsenic-free HBF4, its effect on the mass change profile was mainly associated to anion adsorption. The impact of dissolved HBF4 on the electro-oxidation of formic acid was rationalized in terms of two contributions: current enhancement at low potentials due to the arsenic-assisted formic acid electro-oxidation and inhibition at high potentials due to anion adsorption. [Copyright &y& Elsevier]

Abstract: Instead of a time-invariant voltammetric profile, many electrochemical systems display a cycle-dependent current–potential response. This phenomenon has been referred to as complex voltammetric response and it has been observed during the electro-oxidation of several molecules such as methanol, ethanol, propanol and hydrogen. There are currently two explanations for the surface mechanism underlying this behavior. In one scenario, the complex voltammogram would result from the specific kinetic pathway taken during the forward sweep. In the other explanation, the phenomenon is discussed in terms of the interplay among the surface roughening and subsequent relaxation, and the ohmic drop coupled to a negative differential resistance. We report in this paper a nanogravimetric investigation of the complex voltammetric response in the electro-oxidation of methanol on platinum electrode in both acidic and alkaline media. Different periodic patterns composed of intercalated small and large hysteresis cycles were observed as a function of the applied voltage and the series resistance between the working electrode and the potentiostat. Independently, nanogravimetric results indicated no detectable difference in the delta-frequency versus voltage profile between small and large hysteresis cycles. These findings were interpreted as experimental evidence of the secondary, if any, role played by the very electrochemical reaction on the emergence of complex voltammetric response. [Copyright &y& Elsevier]

Abstract: A catalyst precursor prepared in situ from palladium acetate and a phosphine ligand was used for the Stille cross-coupling reaction of benzylic bromides and chlorides with aryltributyltin analogues. The reactions were performed at 80°C using dppf as ligand in the presence of KF, or more conveniently using PPh3 in the absence of base, furnishing diarylmethane derivatives in high yields (86–99%). Using Pd(OAc)2/PPh3 as catalyst precursor competitive Stille and Suzuki cross-coupling reactions with benzyl chloride showed that in the absence of base or in the presence of KF the Stille product is the majority product, and only the Suzuki product was obtained in the presence of KOH as base. [Copyright &y& Elsevier]

Abstract: Two consecutive cases of ectopic opening of the vas deferens into Müllerian duct cysts are presented, with descriptions of the presentation, physical examination, radiographic and ultrasonographic images, surgical findings and treatment undertaken. In both cases, ablation of the cyst and ligature of the vas deferens was the technique employed. Both patients are currently well, with normal urinary flow and no urinary tract infections, 3years after surgery. Ectopic opening of the vas deferens into Müllerian duct cysts is a rare entity but should always be considered when a child presents with purulent urinary discharge and abdominal tumor. Surgery is the only treatment recommended. [Copyright &y& Elsevier]

Aryl bromides and iodides can be coupled with phenylboronic acid in good yields using NiCl2·6H2O as a catalyst precursor. This nickel complex is cheap, widely available and can be used without any auxiliary ligand or reducing agent. [Copyright &y& Elsevier]

Sulfur-containing palladacycles, in particular those derived from the orthometalation of benzylthioethers, effectively promote the homocoupling of aryl iodides and bromides, under relatively mild reaction conditions to furnish symmetrical biphenyls in good yields. [Copyright &y& Elsevier]