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The noise amplification mode in a plasma maser with inverse geometry was obtained experimentally for the first time. It is shown that the introduction of a microwave absorber transfers the maser operating mode from the oscillator to the amplifier. In both modes, the tuning of the radiation frequency has been shown when the plasma density changes. This work is a step in the implementation of a plasma relativistic noise amplifier with a short REB pulse.

Objectives. To establish the characteristics of the influence of alcoholization on cognitive functions in patients with schizophrenia, Materials and methods. A total of 100 patients with paranoid schizophrenia were studied. A main group (MG) was identified with concomitant diagnosis of alcohol dependence (n = 50), along with a control group (n = 50). The characteristics of memory, attention, and thought were assessed, and the groups were compared in terms of the presence of concomitant addictive pathology. Results. Attention and short-term memory were at the borderline level and no statistically significant differences were seen between the groups studied. In the Benton test, the study group showed a predominance of errors of the schizophrenic type, while the control group was dominated by “organic” errors. A statistically significant dominance of mild decreases in thought were seen in the MG. Conclusions. Concomitant alcohol dependence was not a defining factor in cognitive impairments in patients with schizophrenia, though it introduced a distinct organic stigma to the structure of the patients’ cognitive profile. “Organic” impairments to thought structure in patients with concomitant alcohol dependence were seen. The best measures of attention were seen in patients suffering from shift-like schizophrenia who were healthy in addiction terms. This suggests that the influence of the alcohol factor has different significance in the continuous and episodic/progressive types of schizophrenia.

A change in the operation mode of a plasma maser with a pulse duration of 40 ns from a noise amplifier to a feedback self-oscillator at a power level of up to 10 MW has been experimentally demonstrated for the first time. In the noise-amplifier mode, the radiation power is distributed almost uniformly in a frequency range from 3 to 9 GHz. In the self-oscillator mode, the emission spectrum contains characteristic frequencies of longitudinal oscillation modes of plasma—beam cavity.

Consideration is given to the research status and prospects for development of plasma relativistic microwave electronics as a basis for plasma masers. Possible applications are determined for plasma masers as high-power sources of microwave pulses. Design features of masers and their radiation characteristics are considered with a view to the type of device: self-oscillator, external signal amplifier, or noise amplifier.

To establish an effect of alcohol dependence on the cognitive functions of patients with schizophrenia.One hundred patients with paranoid schizophrenia were examined. Half of them had a co-occurring diagnosis of alcohol dependence syndrome. Memory, attention, thinking were studied. Comparisons were made between groups, depending on the presence of the addictive disorder.Attention and short-term memory are at the low border of normal values in both groups. No significant between-group differences were found. In Benton test, errors characteristic of schizophrenia were more frequent in the main group. 'Organic' errors were prevalent in the control group. Mild thinking disorders of organic type were significantly more frequent in the main group.Co-occurring alcohol dependence does not significantly influence intelligence but significant organic stigmas contribute to the structure of the cognitive profile of patients. The prevalence of organic disturbances in the structure of thinking in patients with co-occurring alcohol abuse was revealed. The best indicators of attention were demonstrated by patients with attack-like schizophrenia without substance abuse. This suggests that the influence of the alcohol factor differs in continuous and attack-like progressive schizophrenia.Цель исследования. Установление особенностей влияния алкоголизации на когнитивные функции больных шизофренией. Материал и методы. Обследованы 100 пациентов, страдающих параноидной шизофренией. Выделены основная группа (ОГ), имеющая сопутствующий диагноз синдрома зависимости от алкоголя (n=50), и контрольная (n=50). Изучены особенности памяти, внимания, мышления, проведено сопоставление групп сравнения по наличию сопутствующей аддиктивной патологии. Результаты. Внимание и краткосрочная память находились на пограничном уровне, между группами сравнения статистически значимо не различались. В тесте Бентона в основной группе преобладали ошибки по шизофреническому типу, тогда как в контрольной группе превалирующими являлись 'органические' ошибки. Прослеживалось статистически значимое преобладание легкого уровня снижения мышления в ОГ. Заключение. Сопутствующая алкогольная зависимость не является определяющим фактором когнитивного поражения больных шизофренией, однако привносит значимые органические стигмы в структуру когнитивного профиля пациентов. Выявлено превалирование 'органических' нарушений структуры мышления у пациентов с сопутствующей зависимостью от алкоголя. Наилучшие показатели внимания отличали пациентов, страдающих шубообразной шизофренией, здоровых в наркологическом плане. Это заставляет полагать, что влияние алкогольного фактора имеет различное значение при непрерывной и приступообразно-прогредиентной шизофрении.

Operated in the noise amplification regime, a plasma maser underwent a series of experiments. The pulse duration was 50 ns, the suppression of feedback was provided by microwave absorbers, transition from the noise amplification to a self-oscillation regime was demonstrated, and the maximum power of 10 MW with the efficiency of 3% was measured. For different plasma concentrations, the linear amplification rate was ranging from 0.1 to 0.2 cm−1. The frequency band of an emission pulse was 3–15 GHz, and the noise spectrum was stable during the pulse. The experiment provided the guidelines for further development, which are in the pulse duration reduction for abandoning the microwave absorber. The short-pulse plasma maser should be ∼35 cm long with the pulse duration

Suicide is one of the main causes of death among patients with mental illnesses. At the same time, alcohol consumption is associated with high risk of autoaggressive and suicidal behavior in population. On the other hand there is an opinion that alcohol may have an illusory-compensatory effect. In that case, alcohol consumption may be an attempt to decrease different symptoms such as depression, anxiety or hallucinations. An analysis of co-occurring schizophrenia and alcohol abuse is presented. Suicide statistics among patients with schizophrenia is studied. Different mechanisms contributing to suicide are highlighted. The correlations of other risk factors with suicide attempts with the assessment of the patient's social resources and environment were studied. The role of alcohol in the presence of other obvious risk factors has been assessed. Possible mechanisms of the protective role of alcohol in relation to suicides among patients with schizophrenia are presented. The authors outline topics of perspective research to clarify the risk of self-destructive behavior in patients with schizophrenia with comorbid alcohol dependence, to search for its predictors and to develop well-grounded complex preventive measures.Среди пациентов, страдающих психическими расстройствами, суицид является одной из основных причин смерти. Вместе с тем алкоголизация сопряжена с высоким риском аутоагрессивного, в том числе суицидного поведения в популяции. С другой стороны, имеется мнение об иллюзорно-компенсаторном действии алкоголя. Злоупотребление алкоголем такими пациентами может быть связано с попытками нейтрализации различных регистров симптоматики, наиболее часто — аффективного (преимущественно тревожно-депрессивные расстройства) и галлюцинаторного. Представлен анализ коморбидности шизофрении и алкогольной зависимости. Проведено изучение статистики по суицидам, преимущественно среди пациентов, страдающих параноидной шизофренией. Сделан акцент на различные механизмы, лежащие в основе суицидальных попыток. Изучены корреляции ряда других факторов риска с суицидными попытками с оценкой социальных ресурсов и окружения пациента. Проведена оценка роли алкоголя в присутствии иных очевидных факторов риска. Представлены возможные механизмы протективной роли алкоголя в отношении суицидов среди пациентов, страдающих шизофренией. Обозначены темы перспективных научных исследований для уточнения риска аутодеструктивного поведения у пациентов, страдающих шизофренией с коморбидной алкогольной зависимостью, поиска его предикторов и разработки обоснованных комплексных профилактических мероприятий.

High frequency optimization of multigap IH-/CH-resonators requires solving the range of problems, particularly receiving high values of effective shunt impedance and realization of the uniform accelerating field distribution on its axes. H-mode resonators design contains flat vanes (pylons)to reach both of these goals. This article presents the results of electrodynamic modeling of CH- and IH-resonators in case of zero gap between the vanes and resonator end wall. The values of the optimized shunt impedances, Q-factor and field flatness for IH- and CH-designs are shown.