Genetic Correlation Between the P300 Event-Related Brain Potential and the EEG Power Spectrum

Previous studies have demonstrated moderate heritability of the P300 component of event-related brain potentials (ERPs) and high heritability of background electroencephalogram (EEG) power spectrum. However, it is unclear whether EEG and ERPs are influenced by common or independent genetic factors. This study examined phenotypic and genetic correlations between EEG spectral power and P300 amplitude using data from 206 Dutch twin pairs, age 16 years. Multivariate genetic models (Cholesky decomposition) were fitted to the observed twin covariances using Mx software. In males, genetic correlations between P300 and EEG power measures were high (0.54-0.74); 30% of the total P300 variance could be explained by genetic factors influencing EEG delta power and 26% by P300-specific genetic factors (total heritability 56%). In females, 45% of P300 variance could be attributed to familial influences that were shared with the EEG. However, it was not possible to distinguish between the genetic versus shared environmental factors, consistent with previous analysis of P300 in this sample (van Beijsterveldt et al., 1998). The results suggest that a substantial proportion of genetic influences on P300 amplitude can be explained by strong heritability of slow EEG rhythms contributing to P300

Beam and target parameters measurement system on helium ions linear accelerator

A system for measuring beam and target parameters on helium ions linear accelerator is presented. The measurement system consists of sensors set, signal converters and computer with codes for processing experimental data. The measurement system is designed for recording, visualizing, storing and processing data directly when samples are irradiated with helium ions with energies of 0.12…4 MeV. The sample temperature, the ion beam current and its shape, the sample tilt angle to the beam axis, the irradiation dose, the ionization, damage and helium range profiles are measured/calculated.Наведено опис системи вимірювання параметрів пучка і мішені на лінійному прискорювачі іонів гелію. Система вимірювань складається з набору датчиків, конвертерів сигналів і ЕОМ з програмою обробки експериментальних даних. Система вимірювань призначена для реєстрації, візуалізації, збереження і обробки даних безпосередньо при опроміненні зразків іонами гелію з енергіями 0,12…4 МеВ. Вимірюються/обчислюються: температура зразка, струм і форма струму пучка іонів на зразку, кут нахилу зразка до осі пучка, доза опромінення, профілі іонізації, пошкоджуваності і залягання гелію в зразку.Приведено описание системы измерения параметров пучка и мишени на линейном ускорителе ионов гелия. Система измерений состоит из набора датчиков, конвертеров сигналов и ЭВМ с программой обработки экспериментальных данных. Система измерений предназначена для регистрации, визуализации, сохранения и обработки данных непосредственно при облучении образцов ионами гелия с энергиями 0,12…4 МэВ. Измеряются/вычисляются: температура образца, ток и форма тока пучка ионов на образце, угол наклона образца к оси пучка, доза облучения, профили ионизации, повреждаемости и залегания гелия в образце

High-voltage modulator of the Linac injector with voltage pulse stabilization

The high-voltage pulse modulator based on the modern semiconductor elements is described. The modulator is intended for use in the power supply system of LINAC helium ions injector and has the ability to smoothly adjust the amplitude (110…150 kV) and the pulse duration (0.5…1 ms). The use of a pulse-to-peak stabilization scheme, made on the basis of a parametric stabilizer with parallel switching of the load, made it possible to increase the accelerated current at the accelerator output by 2 times.Описано високовольтний імпульсний модулятор, виконаний на сучасній напівпровідниковій елементній базі. Модулятор призначений для використання в системі живлення інжектора лінійного прискорювача іонів гелію. Модулятор дозволяє плавно регулювати амплітуду (110…150 кВ) і тривалість імпульсу (0,5…1 мс) напруги. Використання схеми стабілізації імпульсу напруги, виконаної на основі параметричного стабілізатора з паралельним перемиканням навантаження, дозволило збільшити прискорений струм пучка на виході прискорювача в 2 рази.Описан высоковольтный импульсный модулятор, выполненный на современной полупроводниковой элементной базе. Модулятор предназначен для использования в системе питания инжектора линейного ускорителя ионов гелия. Модулятор позволяет плавно регулировать амплитуду (110…150 кВ) и длительность импульса (0,5…1 мс) напряжения. Использование схемы стабилизации импульса напряжения, выполненной на основе параметрического стабилизатора с параллельным переключением нагрузки, позволило увеличить ускоренный ток пучка на выходе ускорителя в 2 раза

Study of the process e+e−→3(π+π−) in the c.m. energy range 1.5–2.0 GeV with the CMD-3 detector

AbstractThe cross section of the process e+e−→3(π+π−) has been measured using a data sample of 22 pb−1 collected with the CMD-3 detector at the VEPP-2000 e+e− collider. 7956 signal events are selected in the center-of-mass energy range 1.5–2.0 GeV. The measured cross section exhibits a sharp drop near the pp¯ threshold. A first study of dynamics of six-pion production has been performed

Development and genetics of brain temporal stability related to attention problems in adolescent twins

The brain continuously develops and reorganizes to support an expanding repertoire of behaviors and increasingly complex cognition. These processes may, however, also result in the appearance or disappearance of specific neurodevelopmental disorders such as attention problems. To investigate whether brain activity changed during adolescence, how genetics shape this change, and how these changes were related to attention problems, we measured EEG activity in 759 twins and siblings, assessed longitudinally in four waves (12, 14, 16, and 18years of age). Attention problems were assessed with the SWAN at waves 12, 14, and 16. To characterize functional brain development, we used a measure of temporal stability (TS) of brain oscillations over the recording time of 5min reflecting the tendency of a brain to maintain the same oscillatory state for longer or shorter periods. Increased TS may reflect the brain's tendency to maintain stability, achieve focused attention, and thus reduce "mind wandering" and attention problems. The results indicate that brain TS is increased across the scalp from 12 to 18. TS showed large individual differences that were heritable. Change in TS (alpha oscillations) was heritable between 12 and 14 and between 14 and 16 for the frontal brain areas. Absolute levels of brain TS at each wave were positively correlated with attention problems but not significantly. High and low attention problems subjects showed different developmental trajectories in TS, which was significant in a cluster of frontal leads. These results indicate that trajectories in brain TS development are a biomarker for the developing brain. TS in brain oscillations is highly heritable, and age-related change in TS is also heritable in selected brain areas. These results suggest that high and low attention problems subjects are at different stages of brain developmen