Use of Remote Surface Based Tools for Visualizing Integrated Brain Imaging Data

We describe a surface-based approach to 3D visualization of integrated neuroimaging data. Our web-enabled software allows researchers to use these visualization tools over the Internet. We present examples of brain imaging studies where such remote surface-based visualization techniques have proven to be quite effective

Brain Visualization in Java3D

BrainJ3D is a cross-platform Java/Java3D software toolkit for processing and visualizing brain imaging data, which 1) contains general purpose tools for reconstructing, mapping and visualizing integrated structural and functional images and 2) leverages Java's Remote Method Invocation to provide both a standalone and a client/server mode

Method for assessing unevenness of cellulose insulation layers aging of power transformers winding

Introduction. Improving the methods of estimating the insulation aging of the oil-immersed power transformer windings is an urgent task for transformer condition monitoring systems. The scientific novelty of the work is to take into account the uneven distribution of temperature and humidity along the vertical axis of the winding in modeling the aging of insulation and to develop methods for determining the conditions under which the aging rate of insulation in the intermediate layer will exceed aging rate in the hottest layer. The purpose of the work is to evaluate the wear unevenness of cellulose insulation based on modeling the distribution of temperature and humidity along the vertical axis of the power transformer winding. Methods. The transformer winding is mentally divided into horizontal layers of equal height, the reduction of service life is calculated in parallel for all horizontal layers. Layer with the maximum degree of aging for the entire period of operation and storage of the transformer is recognized as determining the reduction in the service life of the insulation of the transformer as a whole. A model of the interaction of winding layers is developed, with determination of temperatures, humidity, relative rate of aging of each layer due to temperature and humidity as a function of traditional design parameters such as load, cooling temperature, heat capacity and thermal resistance of transformer. The index of exceeding the aging rate by the layered method in comparison with this rate for the hottest layer is offered. The method of genetic algorithms determines the conditions for obtaining the maximum value of this index. Results. A computer model has been developed to predict the aging of the cellulose insulation of transformer windings. According to the proposed method, a layer with significantly shorter insulation aging time (in the example, time reduced by 39.18 %) than for the upper layer was determined, which confirms the feasibility of layer-by-layer monitoring and modeling of insulation aging processes of power oil-immersed transformer windings.Вступ. Вдосконалення методик оцінки старіння целюлозної ізоляції обмоток силового маслонаповненого трансформатора є актуальним завданням для систем моніторингу стану трансформаторів. Наукова новизна роботи полягає в урахуванні нерівномірності розподілів температури та вологості вздовж вертикальної осі обмотки при моделюванні процесів старіння ізоляції та у розробці методики визначення умов, за яких швидкість зносу ізоляції у проміжному шарі буде максимально перевищувати швидкість у найбільш нагрітому шарі обмотки. Метою роботи є оцінка нерівномірності зносу целюлозної ізоляції на основі моделювання розподілу температури та вологості вздовж вертикальної осі обмотки силових трансформаторів. Методи. Обмотка трансформатора подумки розділена на горизонтальні шари рівної висоти, підрахунок скорочення строку служби виконується паралельно за усіма горизонтальними шарами, а шар, що має максимальний ступінь старіння за весь період експлуатації та зберігання трансформатору визнається найбільш ресурс витратним шаром, який визначає скорочення строку служби ізоляції трансформатора в цілому. Розроблена модель взаємодії шарів обмотки, з визначенням температур, вологості, відносної швидкості старіння кожного шару внаслідок дії температури та вологи як функції традиційних розрахункових параметрів, таких як навантаження, температура охолодного середовища, теплоємність та тепловий опір трансформатора. Запропонований показник перевищення швидкості скорочення строку служби пошаровим методом у порівнянні з цієї швидкістю для найбільш нагрітого шару. Методом генетичних алгоритмів визначені умови для отримання максимального значення цього показника. Результати. Розроблена комп’ютерна модель для прогнозування старіння целюлозної ізоляції обмоток. За запропонованою методикою визначено найбільш ресурс витратний шар зі значно меншим часом старіння ізоляції (у прикладі час зменшено на 39,18 %), ніж для верхнього шару, що підтверджує доцільність пошарового моніторингу та моделювання процесів старіння ізоляції обмоток силового маслонаповненого трансформатора

Unobtrusive Integration of Data Management with fMRI Analysis

We describe a plugin for SPM, a popular fMRI statistical processing package, which interfaces to the Dartmouth Experiment lab book, an ontologybased tool to help researchers manage metadata and maintain it in a uniform format. The SPM plugin permits the creation of batch processing scripts that automatically populate the lab book, thereby hiding the details of data management while permitting researchers to continue using an analysis tool with which they are familiar

Anatomical Parcellation of Cortical Language Sites

Anatomical labeling of cerebral cortical stimulation (CSM) sites is necessary for intelligent computer querying of a rich and unique experimental database examining neural substrates underlying human language production. To this end, we have developed a parcellation scheme for the lateral surface of the human cerebral cortex. We then compared results generated utilizing this approach to those generated using an alternative method implemented in the Talairach Daemon

ON EXISTENCE OF BOUNDED FEASIBLE SOLUTIONS TO NEUMANN BOUNDARY CONTROL PROBLEM FOR p-LAPLACE EQUATION WITH EXPONENTIAL TYPE OF NONLINEARITY

We study an optimal control problem for mixed Dirichlet-Neumann boundary value problem for the strongly non-linear elliptic equation with p-Laplace operator and L1-nonlinearity in its right-hand side. A distribution u acting on a part of boundary of open domain is taken as a boundary control. The optimal control problem is to minimize the discrepancy between a given distribution yd 2 L2( ) and the current system state. We deal with such case of nonlinearity when we cannot expect to have a solution of the state equation for any admissible control. After dening a suitable functional class in which we look for solutions and assuming that this problem admits at least one feasible solution, we prove the existence of optimal pairs. We derive also conditions when the set of feasible solutions has a nonempty intersection with the space of bounded distributions L1( )

Dissociation of Action and Object Naming: Evidence From Cortical Stimulation Mapping

This cortical stimulation mapping study investigates the neural representation of action and object naming. Data from 13 neurosurgical subjects undergoing awake cortical mapping is presented. Our findings indicate clear evidence of differential disruption of noun and verb naming in the context of this naming task. At the individual level, evidence was found for punctuate regions of perisylvian cortex subserving noun and verb function. Across subjects, however, the location of these sites varied. This finding may help explain discrepancies between lesion and functional imaging studies of noun and verb naming. In addition, an alternative coding of these data served to highlight the grammatical class vulnerability of the target response. The use of this coding scheme implicates a role for the supramarginal gyrus in verb-naming behavior. These data are discussed with respect to a functional-anatomical pathway underlying verb naming

Комп’ютерне моделювання характеристик одноелектронних транзисторів

Proposed methods of modeling of electrical and temperature characteristics of single-electrontransistor for providing information to system of computer-aided design Electronics Workbench.Analyzed dependence in current-voltage characteristics of nano-device trough values of temperature andoperating modeРазработаны методы моделирования электрических и температурных характеристик одноэлектронного транзистора для информационного обеспечения системы автоматизированного схемотехническогопроектирования Electronics Workbench. Проанализирована зависимость вольт-амперных характеристик наноприбора от влияния температуры и рабочего режимаРозроблено методи моделювання електричних та температурних характеристик одноелектронного транзистора для інформаційного забезпечення системи автоматизованого схемотехнічного проектування Electronics Workbench. Проаналізовано залежність вольт-амперних характеристик наноприладу від впливу температури таробочого режим

Myosin VI and optineurin are required for polarized EGFR delivery and directed migration.

The polarized trafficking of membrane proteins into the leading edge of the cell is an integral requirement for cell migration. Myosin VI and its interacting protein optineurin have previously been shown to operate in anterograde trafficking pathways, especially for the polarized delivery of cargo to the basolateral domain in epithelial cells. Here we show that in migratory cells ablation of myosin VI or optineurin inhibits the polarized delivery of the epidermal growth factor receptor (EGFR) into the leading edge and leads to profound defects in lamellipodia formation. Depletion of either myosin VI or optineurin, however, does not impair the overall ability of cells to migrate in a random migration assay, but it dramatically reduces directed migration towards a growth factor stimulus. In summary, we identified a specific role for myosin VI and optineurin in directionally persistent cell migration, which involves the polarized delivery of vesicles containing EGFR into the leading edge of the cell

Intrinsic Variability of GM Density Maps and its Implications to VBM Studies

Voxel Based Morphometry (VBM) has been gaining popularity as an unbiased objective neuroimaging technique for identifying structural changes in the brain. VBM involves a voxel-wise comparison of the local concentration of gray matter (GM) in whole brain MRI scans. Although it was originally devised to examine structural abnormalities in patients, the technique has also been used successfully with healthy subjects. Recent VBM studies have investigated the impact of learning and practice on brain structure. Unlike certain medical conditions that may cause dramatic structural changes, effects observed in healthy subjects are expected to be small, therefore imposing stringent requirements on the sensitivity of the technique. The success of such studies depends on high quality imaging and subsequent accurate segmentation of GM. Segmentation results are inevitably affected by the presence of other tissues with similar intensity (dura matter, large blood vessels etc.), imaging artifacts (blood flow and eye movement, susceptibility artifacts etc.). Since these factors are non-homogeneous throughout the brain, segmentation is highly reproducible in some areas of cortex while it is less reliable in other areas. This non-homogeneity makes VBM sensitivity selective to areas where segmentation happens to be more robust. We studied the intrinsic variability of GM density maps derived from scans obtained under identical conditions, i.e. the same subject, scanner and protocol. The data was acquired on GE Signa 1.5, (SPGR) and Philips Achieva 3T (MPRAGE) scanners. A distinction should be made between variability observed among scans acquired within the same session and that observed for different sessions, since the latter will also be affected by such factors as different head positioning and the somewhat altered state of both the subject and the scanner. The figure summarizes within-session variability of GM density maps observed using the GE Signa. Six SPGR scans were obtained in each of four subjects in one session, and the scan sessions were repeated nine weeks later as a part of longitudinal VBM study. Variability for one subject/session was estimated by computing the standard deviation of six GM density maps obtained using SPM5 unified segmentation/normalization framework and VBM5 toolkit. These were normalized by applying a transformation estimated as follows: all six scans were coregistered and averaged to obtain a low noise structural image volume and a single normalization transformation was estimated from it. Eight variability maps in standard (MNI) space corresponding to session/subject pairs were averaged to produce a map shown in the Figure. The color coded variability map is superimposed onto the GM probability density map (only the right hemisphere is shown in the figure). We will present the findings of within and between session variability analyses derived from our data and from data obtained in other laboratories, and discuss implications and methodological considerations for planning and interpreting VBM studies of GM density. Preliminary results indicate that although different scanners and protocols produce varying patterns of GM variability maps, certain areas (e.g. tip of the temporal lobe) may consistently show increased variability