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Introduction. The article presents the results of photodynamic therapy (PDT) of extrahepatic bile ducts (EBD) and large duodenal papilla (LDP) cancer in inoperable patients. The technique of its carrying out and ways of delivery of laser light guides to various parts of biliary tract are described. Efficiency of PDT for cancer of LDP and separately for cancer of EBD was determined. The dependence of patients' life expectancy on the number of PDT sessions during a year was revealed and the comparative analysis of two groups of photosensitizers (PS) efficiency was carried out.Research purpose: to estimate the effectiveness of photodynamic therapy (PDT) in treatment of VUC and IBD cancer; to determine the reasonability of repeated PDT courses and time intervals between them; to compare the effectiveness of photosensitizers Photodetazine and Photosens in treatment of these patients.Materials and Methods. The study was based on a comparative analysis of life expectancy in inoperable groups of patients with VVC and IBD cancer. The main group consisted of 29 patients (including 20 patients with IBD cancer) who were treated by PDT besides biliary operations. Control group consisted of 50 patients (14 of them with BDZ cancer), only biliary drainage interventions were used in their treatment. The number of PDT courses performed was from 1 to 3 during the year. A total of 29 patients underwent 52 courses of PDT. We used two photosensitizers from different groups: Fotoditazin (chlorine derivative E6) – was used in 18 patients and Photosense (phthalocyanine derivative) – was used as PS in 11 patients. Assessment of treatment efficacy was based on determining the median survival according to the Kaplan-Meier method.Results. Median survival time in the main group was 18 months [95% CI: 15.9; 20.1], in the comparison group (without PDT) – 7 months [95% CI: 5.1; 8.9]. In patients with IBD cancer, the median survival for PDT was 18 months [95% CI: 16; 20], and 12 months [95% CI: 9.25; 14.75] in the comparison group. Life expectancy for patients with BDS cancer ranged from 1 to 60 months. Median survival time was 17 months [95% CI: 12; 21] in case of Fotosens – 18 months [95% CI: 16; 19]. In the group of patients who underwent one PDT session during a year, median survival time was 12.5 months [95% CI: 10; 15], in the group of patients who underwent 2 or more sessions, median survival time was 23 months [95% CI: 18; 28].Conclusions. Photodynamic therapy in combination with draining interventions on bile ducts is an effective method of therapy of inoperable forms of IVC and IBD carcinoma in high risk patients. Variants of delivery of laser radiation for PDT are developed. Repeated sessions of PDT at intervals of 4-6 months potentiate the effectiveness of palliative therapy and increase life expectancy of patients. The effectiveness of Fioditazine and Photosense in PDT was found to be similar. Fotoditazine showed a lower number of complications.

A dynamical theory is developed of X-ray diffraction on a crystal with surface relief for the case of high-resolution triple-crystal X-ray diffractometry. Crystals with trapezoidal, sinusoidal and parabolic bar profile models are investigated in detail. Numerical simulations of the X-ray diffraction problem for concrete experimental conditions are performed. A simple new method to resolve the crystal relief reconstruction problem is proposed.

The relevance of the research lies in the fact that this article is one of the first in the last decade that is devoted to the study of metadata of the All-Russian Population Census of 2020. Its purpose is to study the attitude of students to the organization of the census, the structure and content of the questionnaire, forms of participation. The scientific novelty of the work is that it is the first study of the attitude of students enrolled in two universities of the Chuvash Republic to the organization of the 2020 census. The survey of 300 young people showed no complaints about the census organization. Various points of view were expressed about the importance of the information obtained during the population censuses. The most popular among young people was participation in the event through an entry on the portal “Public Services”. The survey materials showed that for students of Chuvash nationality, data on nationality are more important than for students of Russian nationality. The Chuvash turned out to be more active participants in the census. Students reacted favorably or neutrally to the opportunity to indicate their belonging to more than one nationality and one native language during the census. At this, about a third stated that their native languages are Chuvash and Russian, which is unusual for an official survey conducted by the state. The study results are of great practical importance and will be taken into account in the future when organizing upcoming activities on the population census.

Precise determination of the isotope masses of superheavy elements obtained by the complete fusion of 48Ca+ ions with Au, Pb, Bi, U, and Pu targets can provide valuable information on the mechanisms of nuclear reactions leading to the formation of these elements. A specialized multi-turn time-of-flight mass spectrometer is to be used to match the goal. The source of the target isotopes is a DC-280 cyclotron, a «factory of superheavy elements» at the Joint Institute for Nuclear Research (JINR, Dubna, Russia). The point of the problem is that ions of superheavy elements are formed quite rarely even in the specialized accelerator of JINR: during the last experiment, the frequency of their appearance was up to 10 events per day. Precise determination of the mass number requires comparing the time of flight of a superheavy ion through a mass analyzer with the same time for a calibrant ion, the mass number and charge of which are precisely known a priori from the process of its formation. Implementation of such a mass spectrometric analysis required the development of an ion source capable of stable operation for a long time. To solve the problem, a number of ion sources were considered. The choice of an ion source with electron ionization is substantiated. A source with a crucible in which the calibrant evaporates during heating was proposed and tested. Various substances (PbBr2, Nd, C60, fullerene soot) were considered as a calibrant. The mass spectra of these compounds are presented, namely, the spectrum of neodymium compounds and the mass spectrum of fullerene soot. It is shown that the use of fullerene soot is optimal, since the mass spectrum of fullerene soot contains ions in the range of mass numbers from 12 to 800 and higher. Moreover, the mass spectrum of fullerene soot contains many peaks in the mass number region of interest 275 – 300 a.m.u. It has been experimentally shown that the ion intensities within the indicated range differ by less than an order of magnitude which makes the use of fullerene soot a standard sample for calibration of a high-resolution time-of-flight mass spectrometer.

Cholesterol oxidase is a highly demanded enzyme used in medicine, pharmacy, agriculture, chemistry, and biotechnology. It catalyzes oxidation of 3β-hydroxy-5-ene- to 3-keto-4-ene- steroids with the formation of hydrogen peroxide. Here, we expressed 6xHis-tagged mature form of the extracellular cholesterol oxidase (ChO) from the actinobacterium Nocardioides simplex VKM Ac-2033D (55.6 kDa) in Escherichia coli cells. The recombinant enzyme (ChO

The vacuum-arc synthesis of nanopowders based on zirconium oxide and metal-organic framework structures was carried out using a low-pressure arc discharge plasma. The obtained material was studied by several methods (XRF, IR, TEM, DTA). The TEM method showed that Zr-MOK is a highly agglomerated particle of an almost spherical shape. The image clearly shows the crystalline ordering of nanoparticles with a large (about 2 nm) lattice parameter. Particle sizes range from 5 to 30 nm. Average particle size 9.4 nm. XRD showed that the proportion of ZrO relative to Zr-MOK, calculated from the most intense lines of the diffractogram, is 65%. XRF results are in good agreement with IR studies. The DTA curve demonstrates a continuous exothermic process associated with a number of features of the plasma-chemical synthesis and morphology of the resulting nanoparticles, which is in full agreement with studies using transmission microscopy.

The article provides an example of successful simultaneous surgical treatment of a patient with a thrombotic complication after endovascular intervention (Endovascular aneurysm repair, EVAR) in the long-term postoperative period (2 years) in the presence of concomitant gastric cancer, detected during a follow-up examination before planned surgery.

В статье приводятся результаты анкетирования студентов-первокурсников заочного отделения по направлению «Документоведение и архивоведение» Чувашского госуниверситета по вопросам выявления факторов, мотивировавших их к необходимости продолжить образование в вузе по выбранной специальности и самооценки обучающимися уровня формирования собственных профессиональных компетенций после окончания среднеспециальных учебных заведений.

Организация самостоятельной работы студентов на семинарских занятиях с применением технологий самоконтроля и взаимоконтроля является необходимым компонентом образовательного процесса. Эти интерактивные методы работы позволяют развивать у обучающихся самостоятельность, ответственность, умение работать в команде. Активизация учебной работы студентов позволяет реализовать на практике тезис об переходе обучающегося из положения объекта в статус субъекта образовательного процесса.

Using the 1.32 $$\hbox {pb}^{-1}$$ pb - 1 statistics collected at the $$J/\psi $$ J / ψ peak with the KEDR detector at the VEPP-4M $$e^{+}e^{-\, }$$ e + e - collider, we measured the branching fractions of $$J/\psi $$ J / ψ meson decays to the final states 2($$\pi ^{+}\pi ^{-})\pi ^{0}$$ π + π - ) π 0 , $$K^{+}K^{-}\pi ^{+}\pi ^{-}\pi ^{0}$$ K + K - π + π - π 0 , 2($$\pi ^{+}\pi ^{-})$$ π + π - ) and $$K^{+}K^{-}\pi ^{+}\pi ^{-}$$ K + K - π + π - . The results obtained for the decays $$J/\psi \rightarrow $$ J / ψ → 2($$\pi ^{+}\pi ^{-})\pi ^{0}$$ π + π - ) π 0 , $$J/\psi \rightarrow K^{+}K^{-}\pi ^{+}\pi ^{-}\pi ^{0}$$ J / ψ → K + K - π + π - π 0 contradict the measurements performed by other groups in the last century, but agree well with recent results of BABAR and BESIII collaborations.

Luminous blue variables (LBVs) are massive stars that show strong spectral and photometric variability. The questions of what evolutionary stages they represent and what exactly drives their instability are still open, and thus it is important to understand whether LBVs without significant ongoing activity exist, and for how long such dormant LBVs may ‘sleep’. In this paper we investigate the long-term variability properties of the LBV candidate MN 112, by combining its optical and infrared spectral data covering 12 years with photometric data covering nearly a century, as acquired from both modern time-domain sky surveys and historical photographic plates. We analyse the spectra, derive the physical properties of the star by modelling its atmosphere, and use a new distance estimate from Gaia data release 3 (DR3) to determine the position of MN 112 both inside the Galaxy and in the Hertzsprung–Russell diagram. The distance estimation has almost doubled in comparison with Gaia DR2. Because of this, MN 112 moved to upper part of the diagram, and according to our modelling it lies on an evolutionary track for a star with initial mass $M_*=70~\rm M_\odot$ near the Humphreys–Davidson limit. Given the absence of any significant variability, we conclude that the star is a dormant LBV that has now been inactive for at least a century.