New triple molybdate and tungstate Na5Rb7Sc2(XO4)9 (X = Mo, W)

New compounds of the composition Na5Rb7Sc2(XO4)9 (X = Mo, W) were obtained via the ceramic technology. The sequences of chemical transformations occurring during the formation of these compounds were established, and their primary characterization was performed. Both Na5Rb7Sc2(XO4)9 (X = Mo, W) were found to melt incongruently at 857 K (X = Mo) and 889 K (X = W). They are isostructural to Ag5Rb7Sc2(XO4)9 (X = Mo, W), Na5Cs7Ln2(MoO4)9 (Ln = Tm, Yb, Lu) and crystallize in the trigonal crystal system (sp. gr. R32). The crystal structures were refined with the Rietveld method using the powder X-ray diffraction data. The thermal expansion of Na5Rb7Sc2(WO4)9 was studied by high-temperature powder X-ray diffraction; it was shown that this triple tungstate belongs to high thermal expansion materials

Optical study of the polar BM CrB in low accretion state

This paper presents a spectral and photometric study of the poorly studied polar BM CrB. Three states of the polar brightness and signs of transition from one-pole to two-pole accretion mode were found by an analysis of ZTF data. It is shown that the transition from the low state to the high state changes the longitude of the main accretion spot (by $\approx 17^{\circ}$) and increases its elongation (by $\approx 10^{\circ}$). The spectra contain Zeeman absorptions of the H$\alpha$ line which are formed at a magnetic field strength of $15.5\pm1$ MG. These absorptions are likely produced by a cold halo extending from the accretion spot at $\approx {^1/_4}$ of the white dwarf radius. Modeling of the behavior of the H$\alpha$ emission line shows that the main source of emission is the part of the accretion stream near the Lagrangian point L$_1$, which is periodically eclipsed by the donor star. The spectra exhibit a cyclotron component formed in the accretion spot. Its modeling by a simple accretion spot model gives constraints on the magnetic field strength $B=15-40$ MG and the temperature $T_e\gtrsim15$ keV

Triple molybdates one-, one - and three(two)valence metals

The authors thank Ph. D. M. K. Alibaeva, Ph. D. I. A. Gudkova and Ph. D. I. V. Korolkova for participation in the research.The review summarizes experimental data on the phase formation, structure and properties of new complex oxide compounds group - triple molybdates containing tetrahedral molybdate ion, two different singly charged cation, together with tri- or divalent cation. The several structural families of these compounds were distinguished and it shown that many of them are of interest as luminescent, laser, ion-conducting or nonlinear optical materials.The work is executed at partial support of the Russian Foundation for basic research (projects No. 08-03-00384, 13-03-01020 and 14-03-00298)

ПРИМЕНЕНИЕ ХЕМОМЕТРИЧЕСКИХ АЛГОРИТМОВ В СПЕКТРОФОТОМЕТРИЧЕСКОМ АНАЛИЗЕ СМЕСЕЙ АНАЛИТОВ С ПОДОБНЫМИ СПЕКТРАМИ ПОГЛОЩЕНИЯ

Spectrophotometry in combination with chemometric algorithms can be applied for the analysis of mixtures with similar spectral characteristics. The methods of multiple linear regression are recommended to use in analysis of 2 or 3 component mixtures, with the increasing number of analytes it is advisable to use the method of projection to latent structures (PLS). The optimum amount of training samples to construct the PLS - calibration which can determine the components with errors of less than 10-15% was established.Keywords: method of multiple linear regression, method of projection to latent structures, similar absorption spectra(Russian)DOI: http://dx.doi.org/10.15826/analitika.2013.17.3.010P.A. Buryukina, I.V. Vlasova, K.A. SpiridonovaDostoevsky Omsk State University, Omsk, Russian FederationСпектрофотометрия в сочетании с хемометрическими алгоритмами может быть применена для анализа смесей веществ с подобными спектральными характеристиками. Методы множественной линейной регрессии рекомендуется использовать в анализе 2-3-компонентных смесей, при увеличении числа аналитов целесообразно применять метод проекции на латентные структуры (ПЛС). Установлен оптимальный объем обучающих выборок для построения ПЛС-градуировок, при котором удается определять компоненты с погрешностями до 10-15 %.Ключевые слова: метод множественной линейной регрессии, метод проекции на латентные структуры, спектрофотометрический анализ, подобные спектры поглощения.DOI: http://dx.doi.org/10.15826/analitika.2013.17.3.010 Литература1. Simultaneous spectrophotometric-multivariate calibration determination of several components of ophthalmic solutions: phenylephrine, chloramphenicol, antipyrine, methylparaben and thimerosal / M.S. Collado et [al.] // Talanta. 2000. V. 52, № 5. P. 909-920.2. Simultaneous spectrophotometric determination of drugs in pharmaceutical preparations using multiple linear regression and partial least-squares regression, calibration and prediction methods / R.D. Bautista et [al.] // Talanta. 1996. V. 43, № 12. P. 2107-2115.3. Application of partial least-squares regression to the resolution of highly correlated spectra. Simultaneous spectrofluorimetric determination of Al3+, Ga3+ and In3+ / M. Blanco et [al.] // Talanta. 1996. V. 43, № 9. P. 1489-1496.4. Бурюкина П.А., Власова И.В. Применение метода проекции на латентные структуры (PLS) в спектрофотометрическом анализе смесей веществ с подобными спектрами поглощения // Вестник ОмГУ. 2012. № 4. С.92-95.5. Goicoechea H.C., Olivieri A.C. Simultaneous determination of phenobarbital and phenytoin in tablet preparations by multivariate spectrophotometric calibration // Talanta. 1998. V. 47, № 1. P. 103-108.6. Dinç E., Özdemir A., Baleanu D. An application of derivative and continuous wavelet transforms to the overlapping ratio spectra for the quantitative multiresolution of a ternary mixture of paracetamol, acetylsalicylic acid and caffeine in tablets // Talanta. 2005. V. 65, № 1. P. 36-47.7. Diaz T.G., Guiberteau A., Salinas F. Comparison of chemometric methods: derivavtive ratio spectra and multivariate methods (CLS, PCR and PLS) for the resolution of ternary mixtures of the pesticides carbofuran, carbaryl and phenamifos after their extraction into chloroform // Analyst. 1997. V. 122. P. 513-517.8. Niazi A., Yazdanipour A. Simultaneous spectrophotometric determination of cobalt, copper and nickel using 1-(2-thiazolylazo)-2-naphthol by chemometrics methods // Chinese Chemical Letters. 2008. V. 19. P. 860–864.9. Nevado J.J.B., Cabanillas C. G., Salcedo A.M. C. Simultaneous Spectrophotometric determination of three food dyes by using the first derivative of ratio spectra // Talanta. 1995. V. 42, № 2. P. 2043-2051.10. Spectrophotometric multicomponent analysis of a mixture of chlorhexidine hydrochloride and lidocaine hydrochloride in pharmaceutical formulation using derivative spectrophotometry and partial least-squares multivariate calibration / O.A. Donmez et [al.] // Ж. анал. химии. 2010. Т. 65, № 1. С. 33-38.11. Bobrowska-Grzesik E. Determination of amoxycillin and clavulanic acid in some pharmaceutical preparations by derivative spectrophotometry (abstract) // Microchimica Acta. 2001. V. 136. № 1-2. P. 31-34.12. Simultaneous spectrophotometric determination of cadmium, copper and zinc / A.M.G. Odrigueza et [al.] // Talanta. 1993. V. 40, № 12. P. 1861-1866.13. Successive projections algorithm applied to spectral data for the simultaneous determination of flavour enhancers / C.C. Acebalet [al.] // Talanta. 2010. V. 82, № 1. P. 222-226.14. Колесникова С.С., Монахова Ю.Б., Муштакова С.П. Алгоритмы декомпозиции спектров смесей в анализе сплавов // Аналитика и контроль. 2012. Т. 16. № 2. С. 203-209.15. Simultaneous spectrophotometric determination of carbamazepine and phenytoin in serum by PLS regression and comparison with HPLC / Z. Rezaei et [al.] // Talanta. 2005. V. 65, № 1. P. 21-28.16. Kinetic–spectrophotometric determination of theophylline, dyphylline, and proxyphylline by use of partial least-squares regression / H. Iturriaga et [al.] // Analytical and Bioanalytical Chemistry. 2002. V. 374, № 1. P. 33-38.17. Complementary use of partial least-squares and artificial neural networks for the non-linear spectrophotometric analysis of pharmaceutical samples / H.C. Goicoechea et [al.] // Analytical and Bioanalytical Chemistry. 2002. V. 374, № 3. P. 460-465.18. Simultaneous determination of iron, cobalt, nickel and copper by UV-visible spectrophotometry with multivariate calibration / A.M.G. Rodriguez et [al.] // Talanta. 1998. V. 47, № 2. P. 463-470. 19. Ghasemi J., Niazi A., Leardi R. Genetic-algorithm-based wavelength selection in multicomponent spectrophotometric determination by PLS: application on copper and zinc mixture // Talanta. 2003. V.59, № 2. P. 311-/317.20. Власова И.В., Шелпакова А.С., Нагаев А.А.Формирование градуировочных наборов для спектрофотометрического анализа многокомпонентных смесей с применением метода множественной линейной регрессии // Вестник Омского университета. 2010, № 2. С. 99-105.21. Власова И.В., Шелпакова А.С., Вершинин В.И. Спектрофотометрический анализ неразделенных смесей с применением метода PLS: оптимизация объема обучающей выборки // Заводск. лаборатория. Диагностика материалов. 2011. Т. 77, № 4. С. 19-22. 22. Власова И.В., Бурюкина П.А. Спектрофотометрический анализ смесей, содержащих макро- и микрокомпоненты, с применением метода PLS // Вестник ОмГУ. 2012. № 2. С. 119-122.23. ГОСТ 4388-72. Вода питьевая. Методы определения массовой концентрации меди. М.: 1972. 9 с.24. ПНД Ф 14.1:2.44-96. Методика выполнения измерений массовой концентрации ионов кобальта в природных и сточных водах фотометрическим методом с нитрозо-R-солью. М.: 1996. 9 с.25. ГОСТ 18293-72. Вода питьевая. Методы определения содержания свинца, цинка, серебра. М.: 1972. 19 с.26. РД 52.24.494-2006. Массовая концентрация никеля в водах. Методика выполнения измерений фотометрическим методом с диметилглиоксимом. М.: 2006. 12 с. 

АПТАМЕРЫ — НОВЫЕ ФАРМАКОЛОГИЧЕСКИЕ СУБСТАНЦИИ ДЛЯ АНТИКОАГУЛЯНТОВ

A ptamers are a new class of oligonucleotide compounds capable of specific binding to various molecular targets and inhibiting their activity. Aptamers are selected from a library of randomly syn-thesized oligonucleotides (from 20 to 60 nucleotides long) based on their ability to bind to the target molecule. In the future, such primary aptamers can be chemically modified to optimize their structure and increase stability. Aptamers are considered to be chemical (oligonucleotide) analogues of monoclonal antibodies: their specificity is similar to that of antibodies, and they have high affinity to their targets. Aptamers are widely used to create pharmacological medicines. As pharmacological substances, they have a number of benefits over antibodies and other protein molecules. Aptamers are practically non-immunogenic, chemically synthesized without the use of biological producers, and their antidotes can easily be created using complementary sequences. The review highlights reports devoted to the development of new anticoagulant aptamer-based medications. The most detailed studies, both preclinical and clinical (various phases of clinical trials), were performed in relation to the study of aptamers against vWF, factor IX and thrombin.  Аптамеры представляют собой новый класс олигонуклеотидных соединений, способных специфически взаимодействовать с различными молекулярными мишенями и ингибировать их активность. Аптамеры получают путем отбора из библиотеки случайно синтезированных олигонуклеотидов (длина от 20 до 60 нуклеотидов) по их способности к связыванию с молекулой-мишенью. В дальнейшем такие первичные аптамеры могут быть химически модифицированы с целью оптимизации их структуры и повышения стабильности. Аптамеры принято считать химическими (олигонуклеотидными) аналогами моноклональных антител, т. к. они обладают близкими к антителам показателями специфичности и сродства (аффинности) по отношению к своим мишеням. Аптамеры активно используются для создания фармакологических препаратов. Как фармакологические субстанции они обладают рядом преимуществ перед антителами и другими белковыми молекулами. Аптамеры практически неиммуногенны, они синтезируются химическим путем без использования биологических продуцентов, и для них могут быть легко созданы антидоты на основе комплементарных последовательностей. В обзоре рассматриваются работы, направленные на создание новых антикоагулянтных препаратов аптамерной природы. Наиболее подробные исследования, как доклинические, так и клинические (в рамках различных фаз клинических испытаний), были выполнены при изучении аптамеров против фактора Виллебранда, фактора IX и тромбина. 

PN G068.1+11.0: A young pre-cataclysmic variable with an extremely hot primary

© 2016, Pleiades Publishing, Ltd.An analysis of spectroscopic and photometric data for the young pre-cataclysmic variable (PCV) PN G068.1+11.0, which passed through its common-envelope stage relatively recently, is presented. The spectroscopic and photometric data were obtained with the 6-m telescope and Zeiss-1000 telescope of the Special Astrophysical Observatory. The light curves show sinusoidal brightness variations with the orbital-period time scale and brightness-variation amplitudes of Δm = 1.m41, 1.m62, and 1.m57 in the B, V, and R bands, respectively. The system’s spectrum exhibits weak HI (Hβ–Hδ) andHeII λλ4541, 4686, 5411 Å absorption lines during the phases of minimum brightness, as well as HI, HeII, CIII, CIV, NIII, and OII emission lines whose intensity variations are synchronized with variations of the integrated brightness of the system. The emission-line formation in the spectra can be fully explained by the effects of fluorescence of the ultraviolet light from the primary at the surface of the cool star. All the characteristics of the optical light of PN G068.1+11.0 confirm that it is a young PCV containing sdO subdwarf. The radial velocities were measured from a blend of lines of moderately light elements, CIII+NIII λ4640 Å, which is formed at the surface of the secondary due to reflection effects. The ephemeris of the system has been improved through a joint analysis of the radial-velocity curves and light curves of pre-cataclysmic variable, using modelling of the reflection effects. The fundamental parameters of PN G068.1+11.0 have been determined using two evolutionary tracks for planetary-nebula nuclei of different masses (0.7 M⊙and 0.78M⊙). The model spectra for the system and a comparison with the observations demonstrate the possibility of refining the components’ effective temperatures if the quality of the spectra used is improved

Anesthetic management of minimally invasive intervention in children's oncohematology: preoperative patient management protocol

Preoperative patient management protocol in the complex anesthetic support of minimally invasive interventions in pediatric oncology is described. Choice of general anesthesia method was determined by the specific clinical situation by analyzing all of the following factors: airway management, necessity and anticipated duration of unconsciousness, the need for analgesia, necessity and duration of immobilization, prevention of hypothermia, the presence and severity of disturbances in the hemostatic system, comfort for the child and his representatives (parents). Basic techniques of child preoperative examination, as well as the methodology for predicting the risk of perioperative adverse events are described.</p

The intermediate-age pre-cataclysmic variables SDSS J172406+562003 and RE J2013+4002

We have analyzed the physical status of the pre-cataclysmic variables SDSSJ172406+562003 and RE J2013+4002, which have evolved after their common-envelope stage a time t = 10 6-10 7 years. Spectroscopy and photometry of these systems were performed with the 6-m and 1-m telescopes of the Special Astrophysical Observatory. We demonstrate that emission lines in the spectra were formed solely by the reflection of radiation emitted by the white dwarfs on the surfaces of their cool companions, under conditions close to local thermodynamic equilibrium. These effects are also responsible for most of the objects' photometric variability amplitude. However, comparing the light curves of SDSS 172406 from different epochs, we find aperiodic brightness variations, probably due to spottedness of the surface of the secondary. Jointly analyzing the spectra, radial-velocity curves, and light curves of the pre-cataclysmic variables and modeling the reflection effects, we have derived their fundamental parameters. We demonstrate that the secondaries in these systems are consistent with evolutionary models for main-sequence stars and do not have the luminosity excesses characteristic of cool stars in young pre-cataclysmic variables. © 2012 Pleiades Publishing, Ltd