20-Gb/s PolDM Duobinary Transmission Over 350-km SSMF Supported by a Polarization Stabilizer and an Optical Dispersion Compensator

A 20-Gb/s transmission over 350-km standard single-mode fiber exploiting duobinary dispersion robustness and polarization-division multiplexing has been demonstrated. The system performance is evaluated employing an automatic endless polarization stabilizer and a suitably designed transmitter-side optical dispersion compensator.     

Non-Canonical Roles of Tau and Their Contribution to Synaptic Dysfunction

Tau plays a central role in a group of neurodegenerative disorders collectively named tauopathies. Despite the wide range of diverse symptoms at the onset and during the progression of the pathology, all tauopathies share two common hallmarks, namely the misfolding and aggregation of Tau protein and progressive synaptic dysfunctions. Tau aggregation correlates with cognitive decline and behavioural impairment. The mechanistic link between Tau misfolding and the synaptic dysfunction is still unknown, but this correlation is well established in the human brain and also in tauopathy mouse models. At the onset of the pathology, Tau undergoes post-translational modifications (PTMs) inducing the detachment from the cytoskeleton and its release in the cytoplasm as a soluble monomer. In this condition, the physiological enrichment in the axon is definitely disrupted, resulting in Tau relocalization in the cell soma and in dendrites. Subsequently, Tau aggregates into toxic oligomers and amyloidogenic forms that disrupt synaptic homeostasis and function, resulting in neuronal degeneration. The involvement of Tau in synaptic transmission alteration in tauopathies has been extensively reviewed. Here, we will focus on non-canonical Tau functions mediating synapse dysfunction.     

Digital Application of Second Order Generalized Integrator Based Grid Estimator Under Unbalanced and Distorted Voltage Conditions

Abstract

Frequency, amplitude, and phase information of the grid voltage are the main constraints for constructing a robust controller algorithm for grid connected applications under unbalanced and distorted voltage conditions. This paper narrates a simple, robust, straight forward method to estimate the instantaneous positive and negative sequence voltage components under unbalanced and distorted voltage circumstances. A second order generalized integrator (SOGI) is encapsulated to filter out the distorted voltage as well as to generate orthogonal voltage components for the three phases of AC grid. Furthermore, these filtered and orthogonal components are accounted for the calculation of instantaneous symmetrical components. Developed technique is more frequency adaptive compared to conventional phase locked loop (PLL) techniques. A set of test outcome results are provided in this paper based on MATLAB/Simulink simulations with real grid data captured from an industrial plant. Moreover, SOGI based estimator is digitally implemented by using dSPACE ds1103 digital controller to validate the numerical simulation results in accordance with the developed theoretical prediction.     

Trichogin GA IV Alignment and Oligomerization in Phospholipid Bilayers

Trichogin GA IV is a short peptaibol with antimicrobial activity. This uncharged, but amphipathic, sequence is aligned at the membrane interface and undergoes a transition to an aggregated state that inserts more deeply into the membrane, an assembly that predominates at a peptide-to-lipid ratio (P/L) of 1:20. In this work, the natural trichogin sequence was prepared and reconstituted into oriented lipid bilayers. The ¹⁵N NMR chemical shift is indicative of a well-defined alignment of the peptide parallel to the membrane surface at P/Ls of 1:120 and 1:20. When the P/L is increased to 1:8, an additional peptide topology is observed that is indicative of a heterogeneous orientation, with helix alignments ranging from around the magic angle to perfectly in-plane. The topological preference of the trichogin helix for an orientation parallel to the membrane surface was confirmed by attenuated total reflection FTIR spectroscopy. Furthermore, ¹⁹F CODEX experiments were performed on a trichogin sequence with ¹⁹F-Phe at position 10. The CODEX decay is in agreement with a tetrameric complex, in which the ¹⁹F sites are about 9–9.5 Å apart. Thus, a model emerges in which the monomeric peptide aligns along the membrane surface. When the peptide concentration increases, first dimeric and then tetrameric assemblies form, made up from helices oriented predominantly parallel to the membrane surface. The formation of these aggregates correlates with the release of vesicle contents including relatively large molecules.     

Growth characteristics of virulent Bacillus anthracis and potential surrogate strains

The objectives of this study were to compare generation and lag times of virulent Bacillus anthracis strains with those of other Bacillus strains, to identify possible surrogates for growth studies, and to determine if the B. cereus module of the U.S. Department of Agriculture Pathogen Modeling Program (PMP) had predictive value for B. anthracis. Growth characteristics of B. anthracis, B. cereus, B. mycoides, and B. subtilis strains in brain heart infusion broth at pH 6.5, 6.0, and 5.5 were determined by absorbance measurements. Growth curves of B. anthracis Sterne and B. cereus strains appeared similar, and the generation times for strain Sterne fell within the PMP's 95% confidence interval for B. cereus. However, the virulent B. anthracis strains Vollum and Pasteur had shorter generation times than the avirulent Sterne strain and most other surrogates and were lower than the PMP's 95% confidence interval for B. cereus. Growth curves of B. cereus ATCC 9818 and B. subtilis ATCC 6633 were more similar to those of virulent B. anthracis strains, but all potential surrogates had significantly different generation times and lag times under some conditions.     

Adaptive relays for overhead line protection

In the liberalized energy market scenario protective relays play an important role in assuring continuous service in the power system where a malfunctioning could lead to serious damages to a wide number of operators having access to the power system. Considering that power lines are operated many times below a rated load current, in this paper an adaptive procedure is presented in order to manage power distribution systems according to dependability or security requirements. In particular, a procedure to obtain an inverse time trip curve by means of a microprocessor, connected to a relay, is presented. The procedure adapts the trip characteristic depending on the conductor temperature, wind speed, emissivity and solar absorbity and is implemented on a microprocessor Rabbit 2200 considering a Drake conductor, 795 kcmil 26/7 ACSR.     

Identification of ferroresonance based on S-transform and support vector machine

The aim of this paper is to develop a method based on S-transform and Support Vector Machine (SVM) for ferroresonance detection. Using this method ferroresonance can be discriminate from other transients such as capacitor switching, load switching and transformer switching. S-transform (ST) is used for decomposition of signals, feature selection is done by Kernel Principal Component Analysis (KPCA). SVM is used for classification. Ferroresonance data and other transients were obtained by simulation using EMTP program. Results show that the proposed procedure is efficient in identifying ferroresonance from other events.     

Optical analysis of surfaces by second‐harmonic generation: Possible applications to tribology

Optical second‐harmonic generation is a recently developed technique in surface science, the range of applications of which has been steadily broadening. It allows, among other things, the direct probing of molecular adsorption on to a solid substrate from a liquid or gaseous environment. This paper reports on the possibility of applying it to tribological studies. A set of possible experiments that could offer information, in particular, on the working principle of those oil additives, commonly used in the lubricant industry, whose effect derives from surface adsorption, are discussed briefly. In addition, the preliminary results of a first experiment are described.     

Assessment of agronomic, chemical and genetic variability in common basil (Ocimum basilicum L.)

In the present work, agro-morphological characteristics, essential oil composition and randomly amplified polymorphic DNA (RAPD) markers were studied to estimate the relationships among 12 basil (Ocimum basilicum L.) genotypes, belonging to nine known cultivars grown in Italy. The basil cultivars were distinguished on the basis of agro-morphological determinations and constituents of essential oil. Chemical compounds of essential oils were found variable in the various basil cultivars. As a consequence, the plants were classified into main phenotypes and chemotypes. RAPD markers were used in order to assess the genetic relatedness among the basil cultivars. On the basis of their genetic similarities, RAPD analysis allowed to group the samples into two main clusters. One of these included cultivars suitable for food industry, which were also correlated via agro-morphological features. However, the same cultivars produced distinct essential oil profiles, which did not match with results obtained by agronomic and genetic analysis. This fact, maybe, is due to a different genic expression of the key enzymes involved in biosynthetic pathways that produce chemical compounds.     

Assessing the strategic benefits of distributed generation ownership for DNOs

The potential for distributed generation (DG) to act as an alternative distribution planning option is now well-recognised by academia and industry, and could play a significant role in electricity distribution utility operation and design. However, the unbundling requirements of European Directive 2003/54/EC, coupled with traditional network planning approaches adopted by European distribution network operators (DNOs), appear to be hindering development of DG and its deployment for distribution network ancillary services. The incentives - or otherwise - that arise from alternative models of DG ownership by bundled and unbundled distribution utilities are examined here. The preference for the siting and sizing of DG installations by DNOs is simulated using a multi-year multi-period optimal power flow. Broadly based on the recent UK regulatory framework, the DG ownership issue and its potential to influence DG penetration are explored.