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The electricity sector, especially in emerging countries, has experienced several transformations, mainly resulting from the increase of electricity demand. This encourages more investment in the generation sector and causes increasing concerns with the development and improvement of tools for static voltage stability analysis of electrical power systems. In this paper the results of the use of the nonlinear predictor for the tracing of the P-V curves are presented. The predictor is based on Vandermonde interpolating polynomial of second degree allowing to reconstruct a function passing through three known points on the P-V curve. The main benefit of using this predictor occurs in the most heavily loaded part of the P-V curve, i.e., near the maximum loading point. In this region, the nonlinear predictor resembles the curve of solutions trajectory and provides a smaller number of iterations and CPU time in the corrector step compared to some linear predictors. In the corrector step, the magnitude of the nodal voltage is used as a continuation parameter. The tests are performed for a two bus system, IEEE-14 bus system and real large systems, 787 buses, corresponding to parts of South–Southeast Brazilian system. Comparisons are presented, in terms of numbers of iterations and robustness, between the methods that use linear predictors and the nonlinear predictor. [ABSTRACT FROM AUTHOR]

The 1878 marriage of Rose Anna Shedlock and Émile Roux was a closely guarded secret. Shedlock studied medicine at Edinburgh with Sophia Jex-Blake (1840–1912) and her fellow students but is not mentioned by name in the usual accounts of their battle for recognition by the University. Subsequently Shedlock attended the Paris medical school where she probably met Emile Roux who was attached to the military medical school of the Val-de-Grâce before his dismissal in 1876. Documentation of this episode and of Roux’s life over the next two years is fragmentary and inaccurate. Sadly, Shedlock died, probably of tuberculosis, in 1879. In a romanticized and highly inaccurate biography Roux’s niece suggested that Rose Anna contracted tuberculosis from Roux whose life was later blighted by the disease. However, Shedlock was unwell for some years before they married and it seems far more likely that she passed the disease on to him. [ABSTRACT FROM AUTHOR]

In many areas of knowledge, situations in which we have to model and solve optimization problems are recurrent. Among the mathematical theories that support the solution of such problems, convex optimization unveiled to be an important tool. This is mainly due to the existence of algorithms whose computational solution has matured a lot in terms of speed of solution and reliability during the past few years. In this context, it deserves attention the CVX, a system for modeling and solving convex optimization problems. CVX uses the disciplined convex programming concept, which is a set of conventions or rules that permits the verification of convexity and automatic conversion of the problem instance into forms directly handled by the embedded solvers. This tutorial presents CVX in a didactic manner whose objective is to facilitate the learning about using the tool along with disciplined convex programming. Besides a number of examples, the tutorial also provides some applications, their corresponding CVX codes, the numerical solutions and discussions. [ABSTRACT FROM PUBLISHER]

The Compressive Sensing (CS) allows the acquisition of signals already compressed and the posterior reconstruction with much less number of measures than the minimum required by the Nyquist theorem. A subarea of CS which improves the performance at the reconstruction stage is named Model-Based CS. Some works have been developed within this subarea. However, most of them consider only the noise generated by sparse approximation, disregarding the noise generated by the quantization stage and its influence on efficiency and robustness of CS. The objective of this study is to investigate the influence of the noise generated by the quantization stage in Model-Based CS efficiency for images with different levels of sparsity and different distributions of coefficients in the frequency domain. In this work, the image acquisition stage is implemented using the partial Fourier matrix which results in a vector of measures. Then, different steps of uniform scalar quantization are added to this vector and the image reconstruction stage is performed using the Compressive Sampling Matching Pursuit (CoSaMP) on a quadtree model. PSNR and bits rate (BR) are then used to evaluate the efficiency of CoSaMP with quantization noise. The performance of this proposed Model-Based CS using different quantization steps were slightly better than other studies using the same model in terms of PSNR, but with the advantage of obtaining smaller values of bit rate (BR maior que 2 bpp). [ABSTRACT FROM PUBLISHER]

Copyright of Brazilian Journal of Applied Economics / Economía Aplicada is the property of FEA-RP, Universidade de Sao Paulo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lumen Veritatis is the property of Lumen Veritatis and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Galician Journal of Economics / Revista Galega de Economía is the property of Universidad de Santiago de Compostela, Servicio de Publicaciones and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Exacta is the property of Exacta - Engenharia de Producao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The diagnosis of autoimmune Myasthenia Gravis (MG) remains clinical and rests on the history and physical findings of fatigable, fluctuating muscle weakness in a specific distribution. Ancillary bedside tests and laboratory methods help confirm the synaptic disorder, define its type and severity, classify MG according to the causative antibodies, and assess the effect of treatment objectively. We present an update on the tests used in the diagnosis and follow-up of MG and the suggested approach for their application. [ABSTRACT FROM AUTHOR]

Deficits in plasma membrane repair have been identified in dysferlinopathy and Duchenne Muscular Dystrophy, and contribute to progressive myopathy. Although Facioscapulohumeral Muscular Dystrophy (FSHD) shares clinicopathological features with these muscular dystrophies, it is unknown if FSHD is characterized by plasma membrane repair deficits. Therefore, we exposed immortalized human FSHD myoblasts, immortalized myoblasts from unaffected siblings, and myofibers from a murine model of FSHD (FLExDUX4) to focal, pulsed laser ablation of the sarcolemma. Repair kinetics and success were determined from the accumulation of intracellular FM1-43 dye post-injury. We subsequently treated FSHD myoblasts with a DUX4-targeting antisense oligonucleotide (AON) to reduce DUX4 expression, and with the antioxidant Trolox to determine the role of DUX4 expression and oxidative stress in membrane repair. Compared to unaffected myoblasts, FSHD myoblasts demonstrate poor repair and a greater percentage of cells that failed to repair, which was mitigated by AON and Trolox treatments. Similar repair deficits were identified in FLExDUX4 myofibers. This is the first study to identify plasma membrane repair deficits in myoblasts from individuals with FSHD, and in myofibers from a murine model of FSHD. Our results suggest that DUX4 expression and oxidative stress may be important targets for future membrane-repair therapies. [ABSTRACT FROM AUTHOR]