The artificial neural networks based relay algorithm for distribution system high impedance fault detection

The paper presents a practical artificial neural network (ANN) based relay algorithm for electric distribution high impedance fault detection. The scheme utilizes the characteristics of high impedance faults (HIFs) in the resulting waveforms of the three-phase residual current, voltage, admittance and power. By using Fourier analysis, their low order harmonic vectors were evaluated and then fed to a neural network. The network was based on either perceptron or feedforward algorithms. The trained network was verified using other distribution systems.published_or_final_versio

A Rotating Charged Black Hole Solution in f(R) Gravity

In the context of f(R) theories of gravity, we address the problem of finding a rotating charged black hole solution in the case of constant curvature. The new metric is obtained by solving the field equations and we show that the behavior of it is typical of a rotating charged source. In addition, we analyze the thermodynamics of the new black hole. The results ensures that the thermodynamical properties in f(R) gravities are qualitatively similar to those of standard General Relativity.Comment: 9 pages, no figure

Asymptotic behaviour of estimators of the parameters of nearly unstable INAR(1) models

A sequence of first-order integer-valued autoregressive type (INAR(1)) processes is investigated, where the autoregressive type coefficients converge to 1. It is shown that the limiting distribution of the joint conditional least squares estimators for this coefficient and for the mean of the innovation is normal. Consequences for sequences of Galton{Watson branching processes with unobservable immigration, where the mean of the offspring distribution converges to 1 (which is the critical value), are discussed

Alternative Splicing of P/Q-Type Ca2+ Channels Shapes Presynaptic Plasticity

Alternative splicing of pre-mRNAs is prominent in the mammalian brain, where it is thought to expand proteome diversity. For example, alternative splicing of voltage-gated Ca2+ channel (VGCC) α1 subunits can generate thousands of isoforms with differential properties and expression patterns. However, the impact of this molecular diversity on brain function, particularly on synaptic transmission, which crucially depends on VGCCs, is unclear. Here, we investigate how two major splice isoforms of P/Q-type VGCCs (Cav2.1[EFa/b]) regulate presynaptic plasticity in hippocampal neurons. We find that the efficacy of P/Q-type VGCC isoforms in supporting synaptic transmission is markedly different, with Cav2.1[EFa] promoting synaptic depression and Cav2.1[EFb] synaptic facilitation. Following a reduction in network activity, hippocampal neurons upregulate selectively Cav2.1[EFa], the isoform exhibiting the higher synaptic efficacy, thus effectively supporting presynaptic homeostatic plasticity. Therefore, the balance between VGCC splice variants at the synapse is a key factor in controlling neurotransmitter release and presynaptic plasticity

Resist, comply or workaround? An examination of different facets of user engagement with information systems

This paper provides a summary of studies of user resistance to Information Technology (IT) and identifies workaround activity as an understudied and distinct, but related, phenomenon. Previous categorizations of resistance have largely failed to address the relationships between the motivations for divergences from procedure and the associated workaround activity. This paper develops a composite model of resistance/workaround derived from two case study sites. We find four key antecedent conditions derived from both positive and negative resistance rationales and identify associations and links to various resultant workaround behaviours and provide supporting Chains of Evidence from two case studies

Consensus-based statements for the management of mitochondrial stroke-like episodes [version 1; peer review: 2 approved]

BACKGROUND: Focal-onset seizures and encephalopathy are prominent features of a stroke-like episode, which is a severe neurological manifestation associated with subtypes of mitochondrial disease. Despite more than 30 years of research, the acute treatment of stroke-like episodes remains controversial. METHODS: We used the modified Delphi process to harness the clinical expertise of a group of mitochondrial disease specialists from five European countries to produce consensus guidance for the acute management of stroke-like episodes and commonly associated complications. RESULTS: Consensus on a new definition of mitochondrial stroke-like episodes was achieved and enabled the group to develop diagnostic criteria based on clinical features, neuroimaging and/or electroencephalogram findings. Guidelines for the management of strokelike episodes were agreed with aggressive seizure management strongly recommended at the outset of stroke-like episodes. CONCLUSIONS: Our consensus statement defines stroke-like episodes in terms of an epileptic encephalopathy and we have used this to revise both diagnostic criteria and guidelines for management. A prospective, multi-centre, randomised controlled trial is required for evaluating the efficacy of any compound on modifying the trajectory of stroke-like episodes

DENTES DUPLOS: A IMPORTÂNCIA DO DIAGNÓSTICO PRECOCE

Introdução: Dentes duplos são anomalias da formação dentária decorrentes da união de dois germes dentários (fusão) ou da tentativa de divisão destes (geminação). A fusão pode ocorrer entre dois dentes normais ou entre um dente normal e outro supranumerário, é mais frequente na dentição decídua, sendo mais observada em incisivos e caninos, com maior frequência nos incisivos inferiores

A topological insulator surface under strong Coulomb, magnetic and disorder perturbations

Three dimensional topological insulators embody a newly discovered state of matter characterized by conducting spin-momentum locked surface states that span the bulk band gap as demonstrated via spin-resolved ARPES measurements . This highly unusual surface environment provides a rich ground for the discovery of novel physical phenomena. Here we present the first controlled study of the topological insulator surfaces under strong Coulomb, magnetic and disorder perturbations. We have used interaction of iron, with a large Coulomb state and significant magnetic moment as a probe to \textit{systematically test the robustness} of the topological surface states of the model topological insulator Bi$_2$Se$_3$. We observe that strong perturbation leads to the creation of odd multiples of Dirac fermions and that magnetic interactions break time reversal symmetry in the presence of band hybridization. We also present a theoretical model to account for the altered surface of Bi$_2$Se$_3$. Taken collectively, these results are a critical guide in manipulating topological surfaces for probing fundamental physics or developing device applications.Comment: 14 pages, 4 Figures. arXiv admin note: substantial text overlap with arXiv:1009.621

A case of inflammatory pseudotumour of the gallbladder presenting as a big mass of uncertain behavior

Background: Inflammatory pseudotumour has been used to describe an inflammatory or fibrosing tumoral process of an undetermined cause that may involve a variety of organ systems, including the lungs, spleen, liver, lymph nodes, pancreas and extrahepatic bile duct with potential for recurrence and persistent local growth. In this article, we report a patient with a big mass of uncertain nature and behavior.Case presentationA 60-year-old woman presented with a 1-week history of abdominal pain, fever and jaundice. Six months before she had had right upper quadrant pain that was interpreted as biliary colic. A contrast-enhanced CT scan showed a big mass of soft tissue with diffuse infiltration of the gallbladder, displacement of the transverse colon, hepatic flexure and duodenum. For diagnostic distinction between a chronic inflammatory disease or a neoplasm, exploratory laparotomy was required. Intraoperative exploration disclosed a big mass of hard texture involving the gallbladder, with multiple concrements, hepatoduodenal ligament, right and transverse mesocolon, stomach and duodenum.Cholecystectomy was performed, preserving adjacent organs with macroscopic desmoplastic reaction. Histopathologic examination of the gallbladder showed a spindle cell proliferation with diffuse chronic inflammatory infiltrate of lymphocytes, plasma cells and hyalinized fibrous stroma. No vascular invasion or cellular atypia were evident.ConclusionInflammatory pseudotumour is a rare condition and diagnostic distinction from a chronic inflammatory disease or other neoplasm is only possible by histopathologic examination. There is a limited number of case reports in the literature indicating tumor location in the gallbladder