Conductivity, weak ferromagnetism and charge instability in α−MnS\alpha-MnS single crystal

The temperature dependence of resistivity, magnetization and electron-spin resonance of the $\alpha- MnS$ single crystal were measured in temperature range of $5 K < T < 550 K$. Magnetization hysteresis in applied magnetic field up to 0.7 T at $T=5 K, 77 K, 300 K$, irreversible temperature behavior of magnetization and resistivity were found . The obtained data were explained in terms of degenerate tight binding model using random phase approximation. The contribution of holes in $t_{2g}$ and $e_g$ bands of manganese ions to the conductivity, optical absorbtion spectra and charge instability in $\alpha -MnS$ were studied. Charge susceptibility maxima resulted from the competition of the on-site Coulomb interaction between the holes in different orbitals and small hybridization of sub-bands were calculated at $T=160 K, 250 K, 475 K$.Comment: 6 pages, 12 figure

Solid-state synthesis and characterization of ferromagnetic Mn5Ge3 nanoclusters in GeO/Mn thin films

Mn5Ge3 films are promising materials for spintronic applications due to their high spin polarization and a Curie temperature above room temperature. However, non-magnetic elements such as oxygen, carbon and nitrogen may unpredictably change the structural and magnetic properties of Mn5Ge3 films. Here, we use the solid-state reaction between Mn and GeO thin films to describe the synthesis and the structural and magnetic characterization of Mn5Ge3(Mn5Ge3Oy)-GeO2(GeOx) nanocomposite materials. Our results show that the synthesis of these nanocomposites starts at 180°С when the GeO decomposes into elemental germanium and oxygen and the resulting Ge atoms immediately migrate into the Mn layer to form ferromagnetic Mn5Ge3 nanoclusters. At the same time the oxygen atoms take part in the synthesis of GeOx and GeO2 oxides and also migrate into the Mn5Ge3 lattice to form Mn5Ge3Oy Nowotny nanoclusters. Magnetic analysis assumes the general nature of the Curie temperature increase in carbon-doped Mn5Ge3Cx and Mn5Ge3Oy films. Our findings prove that not only carbon, but oxygen may contribute to the increase of the saturation magnetization and Curie temperature of Mn5Ge3-based nanostructures

Novel GLIS3 mutation in patient with neonatal diabetes mellitus and congenital hypothyroidism (NDH-syndrome)

Mutations in the GLIS3 gene encoding the GLIS3 transcription factor are cause of a rare syndromic form of neonatal diabetes mellitus (NDM) with congenital hypothyroidism. Additional features include congenital glaucoma, hepatic fibrosis, polycystic kidneys, developmental delay and other anomalies. This disease in foreign literature is called NDH-syndrome (Neonatal diabetes and Hypothyroidism syndrome).We present the description of a patient with this syndrome with novel homozygous GLIS3 mutation.Our patient is a female, who was born with a weight of 1680 gr, length of 44 cm to consanguineous parents. She developed diabetes on 2 day after birth, requiring continuous intravenous insulin. On day 5 of life hypothyroidism was identified. ­Thyroid anatomy was normal on ultrasound scan. NDH syndrome was suspected.Genetic analysis revealed a novel homozygous mutation c.1836delT, p.Ser612ArgfsTer33 in exon 5 in GLIS3 gene.To date, the patient is followed up for 4 years in total. Currently, growth retardation, psychomotor and speech development persist. Carbohydrate metabolism and thyroid profile has been subcompensated against the background of replacement therapy. No other components of the syndrome have been identified.In this report, we have demonstrated the features of the neonatal diabetes mellitus in a patient with a defect in the GLIS3 gene. Early genetic verification of the diagnosis contributes to the timely starting of personalized therapy, can improve the quality of life of such patients, and, given the nature of inheritance, is necessary for medical genetic counseling of the family

Sediment Resuspension Due to Near-Bed Turbulent Effects: A Deep Sea Case Study on the Northwest Continental Slope of Western Australia

Sediment transport equations often consider a mean velocity threshold for the initiation of sediment motion and resuspension, ignoring event‐based turbulent bursting processes. However, laboratory experiments have suggested that near‐bed sediment resuspension is influenced by intermittent turbulent coherent structures. In the field, accessibility constraints for deployment of easily operated equipment has largely prevented further identification and understanding of such processes, which may contribute to resuspension in the marine environment. Field experiments were conducted on the Northwest Slope, Australia, under conditions where the mean current velocities were below the estimated and measured time‐averaged critical velocity to investigate the relationship between near‐bed turbulent coherent structures and sediment resuspension. Results indicate that sediment resuspension occur even when velocities are below the estimated and measured mean critical values. The majority of turbulent sediment flux is due to ejection and sweep events, with lesser contributions from up‐acceleration and down‐deceleration (vertical flow) events. Spectral and quadrant analysis indicated the anisotropic and intermittent nature of Reynolds stresses, and wavelet transform revealed a group of turbulent bursting sequences associated with sediment resuspension. These observations, in flow conditions where resuspension was not expected to occur based on mean threshold concepts, reveal that intermittent turbulent events control sediment resuspension rather a single time‐averaged critical velocity. This highlights the need of considering turbulence as a significant factor in sediment resuspension and should be further investigated for inclusion into future sediment transport modeling

РЕНТГЕНО-ГРАФИЧЕСКИЙ АНАЛИЗ КАЧЕСТВА СЕМЯН ОВОЩНЫХ КУЛЬТУР

The possibility of application of radiography in production and study of vegetable seeds and its advantages (rapid test method, multipurpose application etc.) are described in the articleПоказаны возможность применения метода рентгенографии в семеноводстве и семеноведении овощных культур, и его достоинства, заключающиеся в его экспрессности, неразрушаемом характере и многоцелевом применении

КОМПЛЕКСНОЕ ПРИМЕНЕНИЕ МЕТОДОВ ОПТИЧЕСКОЙ ДИАГНОСТИКИ ПРИ НЕСПЕЦИФИЧЕСКОМ ЯЗВЕННОМ КОЛИТЕ

Abstract. Our results suggest that the combined use of optical coherent tomography (OCT) and fluorescence diagnosis helps to refine the nature and boundaries of the pathological process in the tissue of the colon in ulcerative colitis. Studies have shown that an integrated optical diagnostics allows us to differentiate lesions respectively to histology and to decide on the need for biopsy and venue. This method is most appropriate in cases difficult for diagnosis. Резюме. Cовместное использование оптической когерентной томографии (ОКТ) и флюоресцентной диа- гностики способствует уточнению характера и границ патологического процесса в ткани толстой кишки при неспецифическом язвенном колите. Исследования показали, что комплексная оптическая диагностика позволяет дифференцировать патологические изменения соответственно гистологической картине и решить вопрос о необходимости биопсии и месте ее проведения. Применение данного метода наиболее целесообразно в трудных диагностических случаях.

Quaternary Selenides EuLnCuSe3: Synthesis, Structures, Properties and In Silico Studies

In this work, we report on the synthesis, in-depth crystal structure studies as well as optical and magnetic properties of newly synthesized heterometallic quaternary selenides of the Eu+2Ln+3Cu+1Se3 composition. Crystal structures of the obtained compounds were refined by the derivative difference minimization (DDM) method from the powder X-ray diffraction data. The structures are found to belong to orthorhombic space groups Pnma (structure type Ba2MnS3 for EuLaCuSe3 and structure type Eu2CuS3 for EuLnCuSe3, where Ln = Sm, Gd, Tb, Dy, Ho and Y) and Cmcm (structure type KZrCuS3 for EuLnCuSe3, where Ln = Tm, Yb and Lu). Space groups Pnma and Cmcm were delimited based on the tolerance factor t’, and vibrational spectroscopy additionally confirmed the formation of three structural types. With a decrease in the ionic radius of Ln3+ in the reported structures, the distortion of the (LnCuSe3) layers decreases, and a gradual formation of the more symmetric structure occurs in the sequence Ba2MnS3 → Eu2CuS3 → KZrCuS3. According to magnetic studies, compounds EuLnCuSe3 (Ln = Tb, Dy, Ho and Tm) each exhibit ferrimagnetic properties with transition temperatures ranging from 4.7 to 6.3 K. A negative magnetization effect is observed for compound EuHoCuSe3 at temperatures below 4.8 K. The magnetic properties of the discussed selenides and isostructural sulfides were compared. The direct optical band gaps for EuLnCuSe3, subtracted from the corresponding diffuse reflectance spectra, were found to be 1.87– 2.09 eV. Deviation between experimental and calculated band gaps is ascribed to lower d states of Eu2+ in the crystal field of EuLnCuSe3, while anomalous narrowing of the band gap of EuYbCuSe3 is explained by the low-lying charge-transfer state. Ab initio calculations of the crystal structures, elastic properties and phonon spectra of the reported compounds were performed. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Funding: The research was supported by the Tyumen region within the framework of the grant agreement in the form of a grant to non-profit organizations no. 89-don dated 07.12.2020. This study was supported by the Ministry of Science and Higher Education of the Russian Federation (project no. FEUZ-2020-0054). This work was supported by state assignment of the Ministry of Science and Higher Education of the Russian Federation (Project Reg. No. 720000Ф.99.1.БЗ85АА13000). The work was conducted within the framework of the budget project № 0287-2021-0013 for the Institute of Chemistry and Chemical Technology SB RAS

Проблема химиорезистентности PRAME-экспрессирующей клетки меланомы и способ ее преодоления c помощью бортезомиба

Background. PRAME gene spontaneous expression is frequently observed in a cancer cell. The protein encoded by this gene increases  the viability of tumour cell. NF-κB signalling pathway takes part in PRAME upregulation. It proposes, that stress conditions may increase the expression level of PRAME in the tumour cell and increase cell’s viability after it. We hypothesized that this phenomenon determines chemoresistance of PRAME-expressing cell, which can be overcome by NF-κB inhibitors, such as bortezomib.Materials and methods. We incubated A875 melanoma cells with cisplatin, bortezomib and dexamethasone, as well as with a mixture  of cisplatin with bortezomib and cisplatin with dexamethasone within 24 hours. To assess the cytotoxicity of these combinations MTT-test was used. For evaluation of PRAME expression level, real-time polymerase chain reaction was used. All data were analyzed with Wilcoxon test for coupled samples.Results. It was found that cisplatin and dexamethasone increased an expression level of PRAME compared to control (p &lt;0.03). The addition of dexamethasone to cisplatin reduced cytotoxic effect of cisplatin. Bortezomib has a cytotoxic effect, but it did not increase the activity  of PRAME gene (p = 0.12). PRAME gene activity in cells incubated with a mixture of cisplatin and bortezomib was observed at a lower level in comparison with cells incubated with cisplatin (p = 0.0277).Conclusion. The results of experiments show that an increase of PRAME expression level reduces the sensitivity of melanoma cells to the cytotoxic effect of cisplatin. PRAME activity increases under stress conditions. Using of bortezomib can inhibit the growth of PRAME expression and makes the tumour cell more vulnerable to cytotoxic agents. On the other hand, dexamethasone may increase a resistance  of PRAME-expressing cell to cytotoxic effects.Введение. В настоящее время показано, что активность раково-тестикулярного гена PRAME, характерная только для опухолевой клетки, может контролироваться сигнальным каскадом NF-κB. Белок PRAME увеличивает жизнеспособность опухолевой клетки. Отсюда следует, что стрессовые условия могут повышать уровень экспрессии PRAME и увеличивать жизнеспособность опухолевой клетки. Мы предположили, что данный феномен определяет химиорезистентность PRAME-экспрессирующей клетки. Эту резистентность можно преодолеть ингибиторами NF-κB-пути, такими как бортезомиб.Материалы и методы: инкубирование в течение суток клеток меланомы линии A875 с цисплатином, бортезомибом и дексаметазоном, смесью цисплатина и бортезомиба, а также со смесью цисплатина и дексаметазона. Для оценки цитотоксичности применяемых препаратов использовали МТТ-тест, уровня экспрессии гена PRAME – полимеразную цепную реакцию в реальном времени. Анализ данных проводили с помощью критерия Вилкоксона для связанных выборок.Результаты. Установлено, что цисплатин и дексаметазон увеличивают уровень экспрессии PRAME по сравнению с клетками меланомы линии A875, не подвергнутыми действию экспериментальных веществ (p &lt;0,03). Добавление дексаметазона к цисплатину снижает цитотоксический эффект последнего. Бортезомиб обладает цитотоксическим действием, но практически не увеличивал активность гена PRAME (p = 0,12). В клетках, инкубированных со смесью цисплатина и бортезомиба, активность гена PRAME находилась на более низком уровне по сравнению с клетками, инкубированными с цисплатином (p = 0,0277).Заключение. Результаты экспериментов показывают, что увеличение уровня экспрессии гена PRAME снижает чувствительность клеток к цитотоксическому действию цисплатина. Активность PRAME увеличивается в условиях стресса. Применение бортезомиба препятствует росту уровня экспрессии PRAME и делает опухолевую клетку более уязвимой к цитотоксическим агентам. С другой стороны, дексаметазон может увеличить резистентность PRAME-экспрессирующей клетки к цитотоксическому воздействию цисплатина