Nonlinear Doppler - Free comb-spectroscopy in counter-propagating fields

The method of Doppler - free comb - spectroscopy for dipole transitions was proposed. The calculations for susceptibility spectrum for moving two-level atoms driving by strong counter propagating combs have been done. The used theoretical method based on the Fourier expansion of the components of density matrix on two rows on kv (v-velocity of group of atoms, k-projection of wave vector) and {\Omega} (frequency between comb components). For testing of validity of this method the direct numerical integration was done. The narrow peaks with homogeneous width arise on the background of Doppler counter. The contrast of these peaks is large for largest amplitudes of comb-components. Power broadening is increasing with increase of field amplitudes. The spectral range of absorption spectrum is determined by the spectral range of comb generator and all homogeneous lines arise simultaneously. The spectral resolution is determined by the width of homogeneously-broadening lines. The physical nature of narrow peaks is in the existence of multi-photon transitions between manifolds of quasi-energy levels arising for different groups of atoms moving with velocities that satisfy to the resonant conditions 2kv= (n+l){\Omega}, where n, l - are integers and {\Omega} - frequency difference between comb teeth

Correction due to finite speed of light in absolute gravimeters

Correction due to finite speed of light is among the most inconsistent ones in absolute gravimetry. Formulas reported by different authors yield corrections scattered up to 8 $\mu$Gal with no obvious reasons. The problem, though noted before, has never been studied, and nowadays the correction is rather postulated than rigorously proven. In this paper we make an attempt to revise the subject. Like other authors, we use physical models based on signal delays and the Doppler effect, however, in implementing the models we additionally introduce two scales of time associated with moving and resting reflectors, derive a set of rules to switch between the scales, and establish the equivalence of trajectory distortions as obtained from either time delay or distance progression. The obtained results enabled us to produce accurate correction formulas for different types of instruments, and to explain the differences in the results obtained by other authors. We found that the correction derived from the Doppler effect is accountable only for $\frac23$ of the total correction due to finite speed of light, if no signal delays are considered. Another major source of inconsistency was found in the tacit use of simplified trajectory models

Technology development for obtaining a multilayer nanoporous aluminum oxide

Experimental preparation of multilayer nanoporous alumina was carried out. The oxide was obtained from aluminum, purity 99.7%. Obtaining aluminum oxide was carried out in a complex electrolyte containing a mixture of acids. The method of mixed multipulse anodizing was applied, using constant current and constant voltage modes. SEM investigated the obtained nanoporous oxide. The geometrical characteristics were determined. A method for controlling the thickness is proposed based on the analysis of changes in the growth rates of anodic alumina

The impact of the time interval from diagnosis to radical prostatectomy on oncological outcomes in high-risk prostate cancer

Introduction. To date, the impact of the time interval from diagnostic prostate biopsy to radical prostatectomy on treatment outcomes remains a topical issue.Objective. To evaluate the effect of the timespan from diagnosis to radical treatment of prostate cancer (PCa) patients on tumor morphology and long-term oncological outcomes.Materials and methods. A retrospective analysis of the results of treatment of patients with high-risk PCa who underwent radical prostatectomy with extended lymphadenectomy from 2001 to 2019 in three St. Petersburg clinics was performed. The influence of the time interval from prostate biopsy to radical treatment on long-term outcomes was assessed.Results. An increase in the time interval before surgical treatment over three months did not affect the tumor morphology. Five-year biochemical relapse-free survival was 79.7%, 67.8% and 52.5% among patients with time interval from biopsy to surgical treatment less than 30 days, 30 – 90 days and more than 90 days, respectively. The time interval prior to radical treatment did not have any effect on overall and cancer-specific survival.Conclusion. The time interval from prostate biopsy to surgical intervention, not exceeding 3 months, is the most favorable with respect to long-term outcomes

Insertion of silica into nanoporous alumina by chemical deposition technique

This paper presents an experimental consideration of the deposition of silicon dioxide in a nanoporous material. The matrix was filled in organic media containing tetraethoxysilane. The analysis of the obtained product on XRD, silica, was carried out using scanning electron microscopy in combination with EDX analysis. The characteristics of the filling of nanopo-rous materials by chemical precipitation from organic liquid media are considered. Electro-physical characteristics of the obtained composite were studied

The effect of a high-protein and high-carbohydrate diet on the content of D-lactate in the blood plasma and intestines of a model organism – rainbow trout

D-lactic acid stereoisomer (D-lactate) is produced by the intestinal microflora and can enter the bloodstream and cause in some cases a condition of acute D-lactic acidemia known as short gut syndrome. The level of D-lactate in blood and in the contents of the intestine is considered as a promising marker of the development of inflammation associated with microflora disorders, as well as with the development of a bacterial infection, while the mechanism of its entry into the blood of vertebrates from the intestine has not been studied in detail.The aim of the study. To investigate the relationship between the level of D-lactate in blood and in the intestine, taking into account the permeability of the intestinal epithelium.Materials and methods. As a model object of the study, we used juvenile rainbow trout O. mykiss. For 54 days, they were high-carbohydrate or high-protein fed. Since different types of bacteria prefer different substrates, it was expected that at the end of the experiment, the composition of the intestinal microflora would be significantly different in fish fed with different diets. The content of D-lactate in blood plasma in vitro was assessed by the Larsen method with modifications; intestinal permeability was assessed by the intensity of fluorescence of the FITС-Dextran stain in the blood of fish. The analysis of the metagenome of samples of the contents and epithelium of the fore and hind intestine was carried out. The hematological profile was partially characterized using blood smears taken immediately after fish blood sampling. By the means of a different diet, it was possible to obtain two groups of fish that differ significantly in the permeability of the intestinal epithelium and in the content of D-lactate in the intestine. At the same time, despite the differences between the experimental groups in the content of D-lactate in the intestine and in intestinal permeability, no significant differences in D-lactate level in blood were found between them. Analysis of the composition of the intestinal microbiome by metabarcoding for the 16S rRNA gene revealed the absence of lactobacilli in the production of D-lactate in fish.Results. It was shown that the mechanism of accumulation of D-lactate in the blood plasma in fish is less associated with increased intestinal permeability or hyperproduction of this metabolite by the intestinal microflora and is more associated with the utilization of D-lactate in the body. In the experiment, it was not possible to achieve a significant change in the species composition of the intestinal microflora of trout under the influence of a highcarbohydrate diet for 54 days compared to fish that received high-protein diet. Some tendencies towards changes in the composition of the microflora were found in the contents of the hindgut, and perhaps with a longer exposure, these changes could reach a statistically significant level

Сравнение результатов лечения больных раком предстательной железы высокого риска по критериям EAU и NCCN

Background. High-risk prostate cancer (PCa) occurs in 15-25 % of newly diagnosed cases and is a life-threatening condition that requires active treatment. In recent years, the percentage of high-risk PCa has significantly increased, as well as the number of prostatectomies performed in patients with unfavorable morphologic features. However, the high-risk group criteria are not fully defined yet. According to various medical associations, a locally advanced or localized disease may have a high risk of progression. Study objective: to evaluate early and long-term results of treatment of patients with high-risk PCa depending on the high-risk group criteria. Materials and methods. The analysis includes results of radical surgical treatment of 832 patients with localized or locally advanced high-risk PCa treated in three medical institutions in St. Petersburg in the period from 2001 to 2019. Clinically high-risk group included patients with one of the following criteria: prostate specific antigen level >20 ng/ml, Gleason score >8, stage (cT); according to the last criterion two groups of patients were identified: HR-EAU (≥cT2c; n = 408) and HR-NCCN (≥cT3a; n = 282). Results. The average prostate specific antigen level was 21.09 and 26.63 ng/ml, respectively, in HR-EAU and HR-NCCN groups (p< 0.0001). The incidence of positive surgical margin, positive lymph nodes (pN+), five-year recurrence-free, cancer-specific, and overall survival did not differ significantly between the clinically high-risk groups. When evaluated according to the criteria obtained from pathomorphological examination of the removed prostate, the HR-NCCN group showed higher frequency of positive surgical margin (24.8 % vs. 19.2 %) and frequency of pN+ (22.4 % vs. 10.4 %). Analysis of long-term outcomes showed less favorable 5-year results in the HR-NCCN group (recurrence-free, cancerspecific, overall survival - 54.8, 87.0, 83.7 %) compared to the HR-EAU group (recurrence-free, cancer-specific, overall survival - 71.0, 92.1, 88.2 %) (p <0.02 for all). Conclusion. Differences in the high-risk group criteria by clinical indicators between associations do not affect early (frequency of positive surgical margin, pN+) and long-term (recurrence-free, cancer-specific, overall survival) outcomes. Pathomorphological indicators are less favorable when evaluated according to NCCN. According to our results, any of the proposed models can be used before radical prostatectomy to determine the prognosis of high-risk PCa patients. However, the NCCN morphological prognostic factors allow better prediction of outcomes and, in accordance with them, prescribe treatment that corresponds to the aggressiveness of the disease.Введение. Рак предстательной железы (РПЖ) высокого риска диагностируется в 15-25 % случаев впервые выявленного заболевания и является угрожающим жизни состоянием, требующим активного лечения. В последние годы число случаев РПЖ высокого риска значимо выросло, как и число простатэктомий, выполненных при неблагоприятной морфологии. Тем не менее критерии высокого риска на сегодняшний день до конца не определены. По данным различных ассоциаций, высокий риск прогрессирования может иметь местно-распространенный или локализованный процесс.Цель исследования - оценить ранние и отдаленные результаты лечения больных РПЖ высокого риска в зависимости от критериев отнесения к группе высокого риска.Материалы и методы. В анализ включены результаты радикального хирургического лечения 832 пациентов в 3 лечебных учреждениях г. Санкт-Петербурга в период с 2001 по 2019 г. по поводу локализованного или местно-распространенного РПЖ высокого риска. Клинически к группе высокого риска относились пациенты с одним из следующих критериев: уровень простатического специфического антигена >20 нг/мл, сумма баллов по шкале Глисона >8, стадия (сТ); по последнему критерию выделено 2 группы высокого риска: ВР-EAU (≥сТ2с; n = 408) и ВР-NCCN (≥сТ3а; n = 282). Результаты. Средний уровень простатического специфического антигена в группах ВР-EAU и ВР-NCCN соответственно составил 21,09 и 26,63 нг/мл (p <0,0001). Частота положительного хирургического края, поражение лимфатических узлов (pN+), 5-летняя безрецидивная опухолевоспецифическая и общая выживаемость между группами клинически высокого риска статистически значимо не различались. При оценке по факторам прогноза, полученным после патоморфологического исследования удаленного материала, в группе ВР-NCCN отмечена более высокая частота положительного хирургического края (24,8 % против 19,2 %) и частота pN+ (22,4 % против 10,4 %). Анализ отдаленных онкологических результатов показал менее благоприятные 5-летние результаты в группе ВР-NCCN (безрецидивная, опухолевоспецифическая и общая выживаемость - 54,8; 87,0 и 83,7 % соответственно) по сравнению с группой ВР-EAU (безрецидивная, опухолевоспецифическая и общая выживаемость - 71,0; 92,1 и 88,2 % соответственно) (p <0,02 для всех). Заключение. Различия ассоциаций в критериях отнесения к группе высокого риска прогрессирования по клиническим показателям не отражаются на ранних (частота положительного хирургического края, pN+) и отдаленных (безрецидивная, опухолевоспецифическая, общая выживаемость) онкологических результатах лечения. Патоморфологические показатели менее благоприятны при оценке по критериям NCCN. С учетом полученных результатов для определения прогноза пациентов с РПЖ высокого риска перед радикальной простатэктомией возможно использование любой из предложенных моделей. Тем не менее оценка морфологических факторов прогноза по критериям NCCN позволяет лучше прогнозировать онкологические результаты и назначить лечение, соответствующее агрессивности заболевания.

A tale of two worlds:assessing the vulnerability of enclave shielding runtimes

status: publishe

ВАРИАЦИИ СИЛЫ ТЯЖЕСТИ И СОВРЕМЕННАЯ ГЕОДИНАМИКА ЮГОЗАПАДНОЙ ЧАСТИ БАЙКАЛЬСКОГО РЕГИОНА

Modern methods for determination of gravity values make it possible to obtain measurements with the accuracy up to 10–9 from g0 of the normal value (up to 1 microgal = 10 m/sec2). While all the systematic and periodic effects are excluded, a question is raised about stability of the gravity field of the Earth over time. Changes of the altitude (the Earth’s radius) with time can be estimated with an accuracy of 0.1 mm by modern space geodetic techniques, such as VLBI method. Our experiments for evaluation of stability of the gravity values over the past decades are based on the data obtained by Russian and foreign observatories using absolute ballistic laser gravimeters. The results put a limit of 10–10 per year to changes of the Earth’s radius. These estimations can be useful for testing hypotheses in tectonics.Measurements of non-tidal variations of gravity (Δg), which were obtained from 1992 to 2012 at the Talaya seismic station (located in the south-western part of the Baikal region), are interpreted together with GPS observation data. At the Talaya seismic station, the linear component of gravity variations corresponds to changes in the elevation of this site. The correlation coefficient is close to the normal value of the vertical gradient of gravity. At this site, coseismic gravity variations at the time of the Kultuk earthquake (27 August 2008, Mw=6.3) were caused by a combined effect of the change of the site’s elevation and deformation of the crust. Our estimations of the coseismic effects are consistent with results obtained by modeling based on the available seismic data.Современные методы определения значения силы тяжести позволяют проводить измерения с точностью до 10–9 от g0 нормального значения (до 1 микрогала = 10 нм/с2). При этом исключаются все систематические и периодические эффекты и возникает вопрос о стабильности поля силы тяжести Земли во времени. Оценить изменения высоты (радиуса Земли) во времени с точностью до 0.1 мм позволяют современные методы космической геодезии (VLBI метод). Экспериментальные оценки стабильности значения силы тяжести за последние десятилетия сделаны по материалам отечественных и зарубежных обсерваторий, использующих абсолютные лазерные баллистические гравиметры. Полученные результаты ограничивают изменение радиуса Земли значением 10–10 в год. Эти оценки можно использовать для тестирования тектонических гипотез.Результаты измерений неприливных вариаций ускорения силы тяжести Δg, проведенных в 1992–2012 гг. на сейсмостанции «Талая» (юго-западная часть Байкальского региона), интерпретируются совместно с данными GPS-наблюдений. Линейная составляющая вариации силы тяжести на станции Талая соответствует изменениям высоты пункта. Коэффициент корреляции близок к нормальному значению вертикального градиента силы тяжести. Косейсмические вариации силы тяжести на этом пункте в эпоху Култукского землетрясения (27.08.2008 г., Мw=6.3) вызваны комплексным эффектом изменения высоты пункта и деформации земной коры. Оценки косейсмических эффектов соответствуют результатам моделирования на основе сейсмологических данных