Три новых чужеродных вида из семейства Chenopodiaceae во флоре России

Three new alien species of Chenopodiaceae s. str. (Amaranthaceae s. l.) are reported for the flora of Russia, the North American Chenopodiastrum simplex and Australian Dysphania carinata and D. pumilio. The identification of the specimens of Chenopodiastrum simplex from Moschny Island in the Leningrad Region (European Russia) was confirmed using both morphological and phylogenetic analyses. Morphologically, C. simplex is very similar to C. badachschanicum having the same fruit and seed characters. A single specimen of Dysphania carinata from Primorye Territory (the Russian Far East) was previously identified as Chenopodium pumilio (≡ Dysphania pumilio) incorrectly. Only recently, the latter species has been indeed found in Beslan town, Republic of North Ossetia - Alania (the North Caucasus). For each species, the possible degree of naturalization is discussed

Development of the World Skills Movement and It’s Significance for Vocational Education

Статья раскрывает проблему нехватки высококвалифицированных кадров, адаптируемых к современным реалиям. Приводится описание особенностей, задач движения World Skills, которое в последние годы набирает популярность в России, занимается подготовкой молодых конкурентоспособных профессионалов, меняет экзаменационную систему в колледжах и вузах, а также выступает связующим звеном между работодателями и молодыми специалистами. Проведенное исследование показало, что присоединение России к чемпионатам World Skills открывает для выпускников профессиональных организаций возможности обмениваться новыми технологиями, повышать уровень профессионального мастерства, приобщаясь к профессиональному опыту других стран.The article reveals the problem of the shortage of highly qualified personnel adapted to modern realities. The features, tasks, and history of the World skills movement, which has been gaining popularity in Russia in recent years, is engaged in training young competitive professionals, changing the examination system in colleges and universities, and also acts as a link between employers and young professionals. The conducted research has shown that Russia’s accession to the World skills championships opens up opportunities for graduates of professional organizations to exchange new technologies, improve the level of professional skills, joining the professional experience of other countries

Insight into the electronic structure of the centrosymmetric skyrmion magnet GdRu2_2Si2_2

The discovery of a square magnetic-skyrmion lattice in GdRu$_2$Si$_2$, with the smallest so far found skyrmion diameter and without a geometrically frustrated lattice, has attracted significant attention, particularly for potential applications in memory devices and quantum computing. In this work, we present a comprehensive study of surface and bulk electronic structures of GdRu$_2$Si$_2$ by utilizing momentum-resolved photoemission (ARPES) measurements and first-principles calculations. We show how the electronic structure evolves during the antiferromagnetic transition when a peculiar helical order of 4$f$ magnetic moments within the Gd layers sets in. A nice agreement of the ARPES-derived electronic structure with the calculated one has allowed us to characterize the features of the Fermi surface (FS), unveil the nested region along the $k_z$ at the corner of the 3D FS, and reveal their orbital compositions. Our findings suggest that the Ruderman-Kittel-Kasuya-Yosida interaction plays a decisive role in stabilizing the spiral-like order of Gd 4$f$ moments responsible for the skyrmion physics in GdRu$_2$Si$_2$. Our results provide a deeper understanding of electronic and magnetic properties of this material, which is crucial for predicting and developing novel skyrmion-based devices.Comment: 13 pages, 8 figure

TREATMENT OF TRIPLE-NEGATIVE BREAST CANCER

The rate of triple-negative breast cancer is 10–24  %, and in recent years it’s one of the most studied subtypes of breast cancer due to its clinical aggressiveness and a small number of molecular targets.The study objective is to evaluate effectiveness of different NAPCT regimens including their dependence on the presence of mutations in the ВRСА 1, 2, СHEK2 genes.Materials and methods. The study included 40 female patients with triple-negative breast cancer. The patients were monitored from 2012 to 2016; surgical treatment was performed at the P.A. Hertzen Moscow Oncology Research Institute – branch of the National Medical Research Radiological Center, Ministry of Health of Russia. Median patient age was 45.9 (31–69)  years. All patients received neoadjuvant polychemotherapy (NAPCT) per different regimens. Then the patients underwent surgery of different volume (from radical mastectomies to resections), and in 25 % of cases reconstructive breast surgery was performed. In 5 patients with BRCA1, – 2 mutations, prophylactic subcutaneous mastectomy with immediate reconstruction with an implant was performed; 2 patients refused prophylactic mastectomy; in 1 patient with СНЕК2 mutation, metachronous multiple primary breast cancer was diagnosed, previously she didn»t undergo prophylactic mastectomy, and 6 years later cancer in the second breast was diagnosed.Results. The study included 11 patients under 40 (27.5 %), 4 (50 %) of them in the group with mutations in ВRCA1, -2, CHEK2.The study demonstrated high effectiveness of NAPCT regimens per the АС + Т scheme and weekly injections of doxorubicin 25 mg/m2, cisplatin 30 mg/m2, and paclitaxel 100 mg/m2. Grade IV treatment pathomorphosis for NAPCT per АС + Т scheme was achieved in 50.0 ± 7.9 % cases, for intensified regimen – in 62.5 ± 12.5 % cases.Median follow-up duration for this patient group was 22.1 months, and during this time disease progression was observed in 3 patients: in the 1st patient continued growth on the thoracic wall and brain metastases were diagnosed, in the 2nd patient – lung and supraclavicular lymph nodes metastases, in the 3rd patient – metastases in the cerebellum. In all of these patients, grade IV treatment pathomorphosis wasn»t achieved. Conclusions. The study demonstrated high effectiveness of NAPCT in patients with triple-negative breast cancer of different stages: objective response rate was 90.0 ± 4.7 %, grade IV treatment pathomorphosis was 50.0 ± 7.9 %.Grade IV treatment pathomorphosis for NAPCT per АС + Т scheme was achieved in 50.0 ± 7.9 % cases, for intensified regimen – in 62.5 ± 12.5 % cases. Rate of grade IV treatment pathomorphosis was higher in patients with hereditary form of the disease (62.5 ± 18.3 %) compared to the group with sporadic breast cancer (46.9 ± 8.8 %), р >0.05. In all patients, 2-year disease-free survival was 92.5 %, 2-year overall survival was 95 %

Insight into the electronic structure of the centrosymmetric skyrmion magnet GdRu2Si2

The discovery of a square magnetic-skyrmion lattice in GdRu2Si2, with the smallest so far found skyrmion size and without a geometrically frustrated lattice, has attracted significant attention. In this work, we present a comprehensive study of surface and bulk electronic structures of GdRu2Si2 by utilizing momentum-resolved photoemission (ARPES) measurements and first-principles calculations. We show how the electronic structure evolves during the antiferromagnetic transition when a peculiar helical order of 4f magnetic moments within the Gd layers sets in. A nice agreement of the ARPES-derived electronic structure with the calculated one has allowed us to characterize the features of the Fermi surface (FS), unveil the nested region along kz at the corner of the 3D FS, and reveal their orbital compositions. Our findings suggest that the Ruderman–Kittel–Kasuya–Yosida interaction plays a decisive role in stabilizing the spiral-like order of Gd 4f moments responsible for the skyrmion physics in GdRu2Si2. Our results provide a deeper understanding of electronic and magnetic properties of this material, which is crucial for predicting and developing novel skyrmion-based systems.We acknowledge the German Research Foundation (DFG) for the support through the grants no. KR3831/5-1, no. LA655/20-1, SFB1143 (project no. 247310070), and TRR288 (no. 422213477, project no. A03). The density functional theory calculations were supported by the Government research assignment for ISPMS SB RAS (project FWRW-2022-0001). E. V. C. acknowledges support from Saint Petersburg State University (project ID no. 94031444). V. S. S. and D. Y. U. work was partially supported by the Ministry of Science and Higher Education of the Russian Federation (no. FSMG-2023-0014) and RSF 23-72-30004. The calculations were partially performed using the equipment of the Shared Resource Center “Far Eastern Computing Resource” of IACP FEB RAS (https://cc.dvo.ru) and Joint Supercomputer Center of the Russian Academy of Sciences (https://rscgroup.ru/en/project/jscc). We also thank the Paul Scherrer Institut, Villigen, Switzerland, for the allocation of ARPES experiments at the ULTRA endstation of the SIS-X09LA beamline of the Swiss Light Source. We acknowledge MAX IV Laboratory for experimental time on beamline BLOCH under proposal 20211066. Research conducted at MAX IV, a Swedish national user facility, was supported by the Swedish Research Council under contract 2018-07152, the Swedish Governmental Agency for Innovation Systems under contract 2018-04969, and Formas under contract 2019-0249.Peer reviewe

Impact of Co atoms on the electronic structure of Bi2Te3 and MnBi2Te4 topological insulators

This work is devoted to an experimental investigation of the electronic structure of the surface of topological insulators of various stoichiometry during the adsorption of Co atoms. Changes in the surface electronic structure of Bi2Te3 and MnBi2Te4 systems upon deposition of Co atoms at various temperatures have been studied using the methods of angle-resolved photoemission spectroscopy, as well as X-ray photoelectron spectroscopy. It is suggested that binding of the adsorbed Co atoms to the substrate surface modifies Dirac point position. The observed changes are associated with the possible formation of magnetic Co-containing ordered surface alloys.This work was supported by the St. Petersburg State University, grant no. 73028629, the Russian Science Foundation, grant no. 18-12-00062, the Russian Foundation for Basic Research, grant nos. 20-32-70127, 21-52-12024, and 18-29-12094, the Science Development Foundation of the President of Azerbaijan, grant no. EIF-BGM-4-RFTF-1/2017-21/04/1-M-02, and in the framework of the state assignment of Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences, and the Rzhanov Institute of Semiconductors Physics, Siberian Branch of the Russian Academy of Sciences.Peer reviewe

Sample-dependent Dirac-point gap in MnBi2Te4 and its response to applied surface charge: A combined photoemission and ab initio study

Recently discovered intrinsic antiferromagnetic topological insulator MnBi2Te4 presents an exciting platform for realization of the quantum anomalous Hall effect and a number of related phenomena at elevated temperatures. An important characteristic making this material attractive for applications is its predicted large magnetic gap at the Dirac point (DP). However, while the early experimental measurements reported on large DP gaps, a number of recent studies claimed to observe a gapless dispersion of the MnBi2Te4 Dirac cone. Here, using micro(μ)-laser angle-resolved photoemission spectroscopy, we study the electronic structure of 15 different MnBi2Te4 samples, grown by two different chemists groups. Based on the careful energy distribution curves analysis, the DP gaps between 15 and 65 meV are observed, as measured below the Néel temperature at about 10–16 K. At that, roughly half of the studied samples show the DP gap of about 30 meV, while for a quarter of the samples the gaps are in the 50 to 60 meV range. Summarizing the results of both our and other groups, in the currently available MnBi2Te4 samples the DP gap can acquire an arbitrary value between a few and several tens of meV. Furthermore, based on the density functional theory, we discuss a possible factor that might contribute to the reduction of the DP gap size, which is the excess surface charge that can appear due to various defects in surface region. We demonstrate that the DP gap is influenced by the applied surface charge and even can be closed, which can be taken advantage of to tune the MnBi2Te4 DP gap size.The authors acknowledge support by the Saint Petersburg State University Grant No. ID 73028629, Russian Science Foundation Grant No. 18-12-00062 in part of the photoemission measurements and total analysis of the results, Grant No. 18-12-00169-p in part of the electronic band structure calculations and Grant No. 20-42-08002 in part of analysis of magnetic properties and Science Development Foundation under the President of the Republic of Azerbaijan Grant No. EI F-BGM-4-RFTF1/2017-21/04/1-M-02. M.M.O. acknowledges the support by Spanish Ministerio de Ciencia e Innovación (Grant No. PID2019-103910GB-I00). K.K. and O.E.T. acknowledge the support from state assignment of IGM SB RAS and ISP SB RAS.Peer reviewe