MAS-MoM Hybrid Method with Wire\u27s Image using in Excitation Problems

An important class of problems is the interaction of an antenna with the cavity of a semi-open metallic structure. In a working environment, an antenna may change its performance due to interactions with its surroundings. This is especially true in automotive applications. Therefore, it is important to consider the interaction of an antenna with possible resonating parts, and to solve these complex electrodynamics problems together. The development of methods for modeling and studying electromagnetic compatibility (EMC) problems has practical value. The method of auxiliary sources (MAS) with the method of moments (MoM) is applied to solve the excitation problem where a wire, with voltage source excitation, is connected to an open metallic surface. For verification of the proposed algorithm, an experimental structure was built and measured. Computer modeling results and the experimental results are in good agreement. Some aspects and principles are described, which provide hybridization of MAS and MoM. Image of objects is effectively applied for the solution of the particular problem

The Method of Auxiliary Sources as an Efficient Numerical Technique for Large 3D Semi Open Structures

The method of auxiliary sources (MAS) has been demonstrated as suitable for solution of diffraction and inverse problems in complex 2D large objects. Based on MAS numerical study of 3D RCS, EMC/EMI and SAR problems, related to the EM field resonance enhancement inside vehicles and the interaction of the cellular telephone radiation with the user\u27\u27s head are given in other work. The objective of this paper is to present details of MAS application to the wide 3D electrodynamic problems. The area of its efficient application, some features and advantages to achieving efficient solutions, are discussed. The extension of the MAS for semi-open structures with partitions is also presented

Electromagnetic Analysis for Vehicle Antenna Development Using Method of Auxiliary Sources

In paper [l] the electromagnetic analysis of large semi-open structures like vehicles was presented formulated as scattering problem, illuminated by a wide range of incident EM fields. The effect of resonances within the semi-open structure on the RCS, near fields and pattem of reradiated fields had been shown. In this paper the interaction of the entire semi-open structure on the performance of an antenna is considered together with the investigation of near field distributions inside the cavity. The Method of Auxiliary Sources (MAS) [2] is utilized. For a simple geometry the results are compared to measurements

Circulating Concentrations of Vitamin B6 and Kidney Cancer Prognosis: A Prospective Case-Cohort Study

Prospective cohort studies have found that prediagnostic circulating vitamin B6 is inversely associated with both risk of kidney cancer and kidney cancer prognosis. We investigated whether circulating concentrations of vitamin B6 at kidney cancer diagnosis are associated with risk of death using a case-cohort study of 630 renal cell carcinoma (RCC) patients. Blood was collected at the time of diagnosis, and vitamin B6 concentrations were quantified using LC-MS/MS. Hazard ratios (HR) and 95% confidence intervals (CI) were calculated using Cox regression models. After adjusting for stage, age, and sex, the hazard was 3 times lower among those in the highest compared to the lowest fourth of B6 concentration (HR4vs1 0.33, 95% CI [0.18, 0.60]). This inverse association was solely driven by death from RCC (HR4vs1 0.22, 95% CI [0.11, 0.46]), and not death from other causes (HR4vs1 0.89, 95% CI [0.35, 2.28], p-interaction = 0.008). These results suggest that circulating vitamin B6 could provide additional prognostic information for kidney cancer patients beyond that afforded by tumour stage

Vitamin D Pathway Genes, Diet, and Risk of Renal Cell Carcinoma

Mediated by binding to the high-affinity vitamin D receptor (VDR), vitamin D forms a heterodimer complex with the retinoid-X-receptor (RXR). Variation in both genes has been shown to modify renal cell carcinoma (RCC) risk. Therefore, we investigated whether VDR and RXRA polymorphisms modify associations between RCC risk and frequency of dietary intake of vitamin D and calcium rich foods, and occupational ultraviolet exposure among 777 RCC case and 1035 controls from Central and Eastern Europe. A positive association was observed in this population between increasing dietary intake frequency of yogurt, while an inverse association was observed with egg intake frequency. RXRA polymorphisms, located 3′ of the coding sequence, modified associations between specific vitamin D rich foods and RCC risk, while RXRA polymorphisms, located in introns 1 and 4, modified associations with specific calcium rich foods. Results suggest that variants in the RXRA gene modified the associations observed between RCC risk and calcium and vitamin D intake

Alcohol increases circulatory disease mortality in Russia: acute and chronic effects or misattribution of cause?

Background There is a consensus that the large fluctuations in mortality seen in Russia in the past two decades can be attributed to trends in alcohol consumption. However, the precise mechanisms linking alcohol to mortality from circulatory disease remain unclear. It has recently been argued that a substantial number of such deaths currently ascribed to cardiovascular disorders are misclassified cases of acute alcohol poisoning

Взаимодействие факторов окружающей среды и генетического полиморфизма в этиологии злокачественных опухолей

Еnvironmental and lifestyle factors play a dominant role in etiology of cancer. In addition, genetic factors significantly influence interindividual variation in cancer incidence. The epidemiological studies in which effects of genetic polymorphism on the risk of cancer have been elucidated are somewhat disappointing. An important problem of these studies is their size. Moreover some of them do not have information on life-style and environmental exposures. The epidemiological method used to investigate the effect of genetic polymorphism on cancer risk is a retrospective case-control study. The chance of discovery of the specific «frequent» allelic variant which is associated with small increase in the risk is higher in studies including large numbers of cases and controls. This paper reviews the epidemiologic studies conducted in Department of epidemiology (Institute of carcinogenesis, Russian N. N. Blokhin Cancer Research Centre) in cooperation with countries of Central and Eastern Europe (Hungary, Poland, Romania, Slovakia) and coordinated by the International Agency for Research on Cancer (IARC). We will cover the studies, in which an attempt has been made to investigate the interaction between polymorphisms of phase 2 xenobiotic metabolism genes (GST), alcohol and aldehyde-metabolizing genes (ADH, ALDH), folate metabolism genes (MTHFR, TYMS) and CHECK2 with environmental and life-style factors in etiology of cancers of the lung, kidney and upper aerodigestive tract. The analyses of these studies suggest that genetic polymorphism modifies the effect of environmental exposures (including occupational carcinogens) and life-style factors (including tobacco, alcohol and diet) on the risk of cancer. The risk of cancer associated with known carcinogenic exposure may increase or decrease depending on the genotype. Interaction between exposure to carcinogenic factor and genotype is a major and significant determinant of cancer risk. Spontaneous tumors develop as a result of a combined effect of environmental factors and genetic polymorphism or endogenous and exogenous factors.Доминирующую роль в этиологии злокачественных опухолей играют факторы окружающей среды и образа жизни человека. В то же время индивидуальный риск развития рака определяется генетической предрасположенностью. Вопросу влияния генетического полиморфизма на риск развития опухолей посвящено множество работ. Однако их результаты разочаровывают. Главной проблемой этих исследований является небольшое количество наблюдени. Кроме того, во многих работах не учитывалась информация о факторах окружающей среды и образа жизни пробандов. Метод случай–контроль – основной эпидемиологический метод изучения генетических вариантов, влияющих на риск развития рака. Для выявления часто встречающихся вариантов, влияние которых на риск невелико, необходимы большие выборки больных и контрольной группы. В связи с этим многоцентровое исследование – принятый метод в области молекулярной эпидемиологии. В настоящем обзоре представлены результаты многоцентровых молекулярно-эпидемиологических исследований, проведенных в отделении эпидемиологии НИИ канцерогенеза РОНЦ им. Н. Н. Блохина совместно с коллегами из стран Центральной и Восточной Европы (Венгрия, Польша, Румыния, Словакия). Исследование координировало Международное агентство по изучению рака (Лион, Франция). Работы, включенные в обзор, посвящены изучению роли полиморфизма генов II фазы метаболизма ксенобиотиков (GSTM1 и GSTT1), алкогольдегидрогеназы (ADH1В и ADH1C) и альдегиддегидрогеназы (ALDH2), метаболизма солей фолиевой кислоты – метилентетрагидрофолатредуктазы (MTHFR) и тимидилатсинтетазы (TYMS) и гена CHECK2 в этиологии рака легкого, верхних дыхательных и пищеварительных органов и почки. Анализ проведенных исследований позволяет заключить, что генетический полиморфизм модифицирует риск развития рака в результате экспозиции к тому или иному внешнему фактору. Показатель P, который характеризует взаимодействие (интеракцию) между влиянием фактора окружающей среды и определенным генотипом и риском развития рака, часто имеет статистически достоверное значение. Таким образом, большинство спонтанных опухолей человека развиваются в результате взаимодействия генетического полиморфизма и внешних факторов