Abdominal epilepsy in an adolescent with bilateral perisylvian polymicrogyria

PURPOSE: We report a patient with recurrent episodes of severe periumbilical pain accompanied by headache, pallor, dizziness, and visual hallucinations who was subsequently diagnosed as having abdominal epilepsy and a bilateral sylvian cortical malformation. METHODS AND RESULTS: During an EEG examination, the patient had a simple partial seizure, manifested as intense abdominal pain. The ictal EEG showed a focal electrographic seizure arising from the left frontotemporal region. Computed tomography scan was normal; however, magnetic resonance imaging (MRI) revealed asymmetric lesions involving both sylvian fissures compatible with polymicrogyria. Onset of treatment with sodium valproate was followed by a significant reduction of seizures. CONCLUSIONS: Abdominal epilepsy should be suspected in adolescents or adults with paroxysmal episodes of abdominal pain associated with migraine-like symptoms. EEG and MRI investigations are indicated. A developmental brain disorder should be considered as a possible etiology.     

Study of various interventions in the façades of a historical building—Methodology proposal,chromatic and material analysis

Visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), and energy dispersive X‐ray spectroscopy (EDS) in addition to scanning electron microscopy (SEM) have been used for determining the color and chemical composition of the architectural elements of the façades of a historical building, which today is the seat of the Diputación Provincial of Cadiz. It dates from 1770 and was built as Custom Headquarters. It is near the port and is almost encircled by the walls of the city. The determination of the color and chemical composition of the materials that provoke this color and the determination of the layers found in the extracted samples from significant zones allow to define the various interventions over the façade and to localize the time in which they were made. This is possible by comparing with graphical registries and historical documentation. The objective is a study of the color of the different façades that the building has had in order to know the history of the building and to choose materials and colors that should be used in a restoration intervention of this historical building. © 2005 Wiley Periodicals, Inc. Col Res Appl, 30, 382–390, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.     

On the inclusion of chain defects in the polyethylene lattice a statistical approach

Summary A simple statistical calculation leads to a relation between crystallinity and concentration of defects () times crystallite thickness yielding the average inclusion of chain defects per crystalline chain segment as an independent parameter. Comparison of X ray crystallinity data for branched isothermically crystallized polyethylene (PE) with buthyl or longer side sequences with our statistical predictions confirms inclusion of up to one defect per 100 carbon atoms (depending on ) within the crystal lattice. These results are in good agreement with values derived from unit cell expansion measurements.     

Distribution of chain defects and microstructure of melt crystallized polyethylene

A combined study using wide-angle X-ray diffraction (WAXD) and small-angle X-ray diffraction (SAXD) of a series of mostly low density polyethylenes with a wide range of chain defect concentrations (0.1–7%) crystallized from the melt is reported. The data presented here complement the earlier results obtained by Swan⁷ and Holdsworth and Keller⁸ for copolymers. The concurrent unit cell expansion and long period decrease with increasing chain defect concentration leads to a picture of chain defects (branches, unsaturations) being distributed between the crystalline lamellae and the surface layer. Based on a model which assumes inclusion of defects within the lattice by means of a generation of 2gl kinks, (supported by the parallel increase of paracrystallinity) an estimation of the concentration of chain defects, ?_c, incorporated into the crystal lattice (<1%) is attempted. The density of defects in the non-crystalline regions, ?_a, turns out to be substantially larger than ?_c and supports the view of a clustering of defects, ?_c and ?_a are both increasing functions of ? with a tendency to level off for ? > 6. According to this model, the fraction of defects incorporated into the lattice does not exceed 20% of the total number of defects in any of the samples investigated. The fraction of defects excluded from the lattice (>80%), on the other hand, sets a higher permissable limit to the crystal thickness value achieved.     

Influence of physical ageing on the α dielectric relaxation of poly(methyl acrylaie)

Summary In this work are examined changes of the relaxation spectrum of PMA during the structural relaxation process which follows a quenching from a temperature T_o above T_g to another T₁ below T_g, which is mantained constant. It is found that the relaxation times spectrum is shifted towards longer times as the ageing time increases. At the same time, its form becomes more and more wide, approaching the form of the relaxation times spectrum calculated at temperatures above T_g from alternative dielectric measurements. A parameter measuring the shift of the spectrum, a(t_a), is defined and its dependence on ageing time and annealig temperature is studied. The effective relaxation time of the structural relaxation process is calculated from a(t_a) and it is found dependent on the temperature of annealing as well as on the value of a(t_a)itself.     

Diamagnetic properties of polyethylene

A novel approach which accounts for the independent contributions to the specific diamagnetic susceptibility (_m) of the amorphous and crystalline phases in, both, the solid and the liquid state of a series of low density polyethylenes (PE) is reported. The dependence of diamagnetism, for each phase contribution, on crystallinity is derived. The much larger rate of increase found for the diamagnetic contribution of the amorphous regions to _m is in accordance with the major influence of defects, perturbing the packing of chain segments rejected from the crystals. A parallel discussion for the liquid state favours the occurrence of a local mesomorphic state above the melting point.Part I. J. Macromol Sci. Phys., B22 (3), 451 (1983)     

Low-cost single-stage electronic ballast based on aself-oscillating resonant inverter integrated with a buck-boost PFCcircuit

In this paper, a new solution to implement and control a single-stage electronic ballast based on the integration of a buck-boost power-factor-correction stage and a half-bridge resonant inverter is presented. The control signals are obtained from the inverter resonant current by means of a saturable transformer. Core saturation is used to control the required dead time between the control pulses of both switches. Since no special integrated circuits are required to control the ballast, the total number of components is minimized and the final cost of the ballast is reduced compared to a typical two-stage configuration. Analysis and basic design guidelines are presented in the paper, together with experimental results obtained from a laboratory prototype     

Development of a distributive control scheme for fluorescent lighting based on LonWorks technology

In this paper, a new distributive control system for indoor fluorescent lighting based on LonWorks technology is presented. The system features the following elements: microprocessor-controlled fluorescent lamp electronic ballast, communication system using the power line as communication media, and control software for Windows 95 environment. The electronic ballast has been especially designed to be operated under the proposed distributive control system. Thus, it features high-input power factor, high-frequency lamp supply, lamp power regulation against line voltage variations, dimming capability, and lamp failure detection. With this scheme, a low-cost distributive control system for lighting applications has been achieved, allowing energy and maintenance savings and increase in the reliability of the fluorescent lighting systems.     

Petri nets‐based model for the analysis of NORIA protocol

Network rOle‐based Routing Intelligent Algorithm is a novel routing algorithm for wireless sensor networks, which combine various effective techniques in order to reduce energy consumption and improve data routes. This algorithm uses role assignment for distributing tasks over the network nodes and fuzzy logic for making decisions. There is a clear need for the use of formal methods to validate the correctness of the protocols as well as performance and functionality prior to the deployment of such algorithms in a real environment. This paper presents a formal and rigorous study of Network rOle‐based Routing Intelligent Algorithm. Prioritised‐timed coloured petri nets (PTCPNs) have been chosen as an appropriate modelling language. In this way, PTCPNs have been used to describe complete and unambiguous specifications of system behaviour, whereas CPNTools is used to evaluate the correctness of the protocol using state space exploration and for performance evaluation using simulation. Copyright © 2015 John Wiley & Sons, Ltd.     

Potential use of visible and near infrared reflectance spectroscopy for the estimation of nitrogen fractions in forages harvested from permanent meadows

One‐hundred and ninety‐two herbage samples from permanent meadows located in the mountains of León (NW Spain) were analyzed for total nitrogen (total N), nitrogen in trichloroacetic acid precipitated matter (TCAN), borate–phosphate buffer insoluble nitrogen (BPBN), neutral‐detergent insoluble nitrogen (NDIN) and acid‐detergent insoluble nitrogen (ADIN). These data were used to calculate the partition of nitrogen fractions proposed by the Cornell Net Carbohydrate and Protein System (CNCPS): A (total N ? TCAN), B₁ (TCAN ? BPBN), B₂ (BPBN ? NDIN), B₃ (NDIN ? ADIN) and C (ADIN). Near‐infrared reflectance spectroscopy (NIRS) technology accurately predicted total N, TCAN and NDIN, as judged by coefficient of determination (R²) and ratio performance deviation (RPD) values greater than 0.90 and 2.5, respectively. The rest of the insoluble N fractions (BPBN and ADIN) were predicted with less accuracy by NIRS. Estimations of CNCPS N fractions (A, B₁, B₂, B₃ and C) using visible–NIR spectra of forage samples did not allow accurate predictions (R² < 0.90; RPD < 2.5). Copyright © 2005 Society of Chemical Industry