165 research outputs found
On the cohomology of the Losev–Manin moduli space
Get PDFWe determine the cohomology of the Losev--Manin moduli space of pointed genus zero curves as a representation of the product of symmetric groups \Sg_2 \times \Sg_n
Optical trapping with superfocused high-M2 laser diode beam
Get PDFMany applications of high-power laser diodes demand tight focusing. This is often not possible due to the multimode nature of semiconductor laser radiation possessing beam propagation parameter M2 values in double-digits. We propose a method of 'interference' superfocusing of high-M2 diode laser beams with a technique developed for the generation of Bessel beams based on the employment of an axicon fabricated on the tip of a 100 μm diameter optical fiber with highprecision direct laser writing. Using axicons with apex angle 1400 and rounded tip area as small as similar to 10 μm diameter, we demonstrate 2-4 μm diameter focused laser ` needle' beams with approximately 20 mu m propagation length generated from multimode diode laser with beam propagation parameter M2= 18 and emission wavelength of 960 nm. This is a few-fold reduction compared to the minimal focal spot size of ∼11 μm that could be achieved if focused by an 'ideal' lens of unity numerical aperture. The same technique using a 1600 axicon allowed us to demonstrate few-μm-wide laser 'needle' beams with nearly 100 μm propagation length with which to demonstrate optical trapping of 5-6μm rat blood red cells in a water-heparin solution. Our results indicate the good potential of superfocused diode laser beams for applications relating to optical trapping and manipulation of microscopic objects including living biological objects with aspirations towards subsequent novel lab-on-chip configurations
Guidance for spiritual mentors. Polemical letters of A. F. Losev in context of discussion about the attitude to july Declaration of metropolitan Sergius (Stragorodsky)
No full textThe documents published here were created in the period and in the context of church controversy that took place after the release of the July Declaration of Metropolitan Sergius (Stragorodsky). They date back from the beginning of 1928. The author of the publication puts forward the hypothesis that the two letters belong to the famous philosopher and church fi gure A. F. Losev but were written under the infl uence of the leader of the church opposition Mikhail Alexandrovich Novoselov. Both philosophers were arrested following the case of the “True Orthodox Church”, M. N. Novoselov in 1929, A. F. Losev in 1930. The publication contains two letters to the clergy by A. F. Losev. One of them, the “Letter to the Defender of the Russian Church”, as suggested by the publisher, is addressed to the Athonite elder-Imiaslavets (Russ. имяславец, literally ‘name-praiser’) archimandrite David (Mukhranov). The other, entitled “NN’s Letter to the Elder”, is addressed to the monk of closed-down Zosima’s Hermitage (Зосимова пустынь) Dosifei (Shonin). The letters give reasons for the open severance from Metropolitan Sergius and condemns the compromising or cautious approach to the problem of severance. Looking like a personal document, the letters are designed for a broad audience and bear the function of convincing and attracting adherents of a certain opinion. The letters illustrate a complicated approach to the problem of obeying spiritual authorities, i.e. spiritual fathers and church authorities. Besides, the documents are interesting as a source of information on the church situation in the late 1920s and as a refl ection of complicated spiritual and personal relations arising in this situation. The letters have been discovered in the State Archive of the Russian Federation and in the Central Archive of the Federal Security Service
Assessment of immune responses to H5N1 inactivated influenza vaccine among individuals previously primed with H5N2 live attenuated influenza vaccine
No full textDuring the past decade, a number of H5 subtype influenza vaccines have been developed and tested in clinical trials, but most of them induced poor serum antibody responses prompting the evaluation of novel vaccination approaches. One of the most promising ones is a “prime-boost” strategy, which could result in the induction of prompt and robust immune responses to a booster influenza vaccine following priming with homologous or heterologous vaccine strains. In our study we evaluated immunogenicity of an adjuvanted A(H5N1) inactivated influenza vaccine (IIV) in healthy adult subjects who received A(H5N2) live attenuated influenza vaccine (LAIV) 1.5 years earlier and compared this with a group of naїve subjects. We found that priming with A(H5N2) LAIV induced a long-lasting B-cell immunological memory against influenza A(H5N1) virus, which was brought on by more prompt and vigorous antibody production to a single dose of A(H5N1) IIV in the primed group, compared to the naїve controls. Thus, by day 28 after the first booster dose, the hemagglutination inhibition and neutralizing (MN) antibody titer rises were 17.2 and 30.8 in the primed group, compared to 2.3 and 8.0 in the control group, respectively. The majority (79%) of the primed individuals achieved seroprotective MN antibody titers at 7 days after the first dose of the IIV. All LAIV-primed volunteers had MN titers ≥ 1:40 by Day 28 after one dose of IIV, whereas only 58% subjects from the naїve control group developed similar immune responses at this time point. The second A(H5N1) IIV dose did not increase the immune response in the LAIV- primed group, whereas 2 doses of IIV were required for naїve volunteers to develop significant immune responses. These findings were of special significance since Russian-based LAIV technology has been licensed to WHO, through whom the vaccine has been provided to vaccine manufacturers in India, China and Thailand - countries particularly vulnerable to a pandemic influenza. The results of our study will be useful to inform the development of vaccination strategies in these countries in the event of a pandemic © 2015, Larisa Rudenko, Anatoly Naykhin, Svetlana Donina, Daniil Korenkov, Galina Petukhova, Irina Isakova-Sivak, Igor Losev, Marina Stukova, Mariana Erofeeva, Alexandra Nikiforova, Maureen Power, and Jorge Flores
On traces of operators associated with the actions of compact Lie groups
No full textLet M be a compact smooth closed manifold, and G a discrete group. A G-operator on M is an operator of finite sum defined by D=sumlimits_{gin G} D_gPhi_g:H^s(M)to H^{s-m}(M), where the D_g are (pseudo)differential operators with orders m and gto Phi_g is a representation of the group G by operators which operate on functions on M. par The main aim of this paper is to study a new class of elliptic G-operators, associated with a representation of the group G by quantum canonical transformations Phi_g. par The following theorem is the main theorem of this paper: par Theorem 2. Let the G-operator 1+D:L^2(M)to L^2(M) be elliptic. Then 1+D is Fredholm
СОРБЦИОННО-ФОТОМЕТРИЧЕСКОЕ И ТЕСТ-ОПРЕДЕЛЕНИЕ ОБЩЕГО СОДЕРЖАНИЯ ЖЕЛЕЗА В ПРИРОДНЫХ ВОДАХ С ИСПОЛЬЗОВАНИЕМ СОРБЕНТОВ НА ОСНОВЕ ОКСИДА ЦИРКОНИЯ, МОДИФИЦИРОВАННОГО ПОЛИГЕКСАМЕТИЛЕНГУАНИДИНОМ, ФЕРРОЗИНОМ И ФЕРЕНОМ С С.Л. Дидух, А.Н. Мухина, В.Н. Лосев
Get PDFThe zirconium oxide based sorbents were prepared by modifying polyhexamethylene guanidine, Ferrozine or Ferene S. Optimal conditions were found for modifying the zirconium oxide by Ferrozine and Ferene S. The sorption capacity of the sorbents is 25 mM/g for Ferrozine and 5 mM/g for Feren S. The sorbents quantitatively extract the iron(II) from solutions of pH 2.5 – 7.0. Intensively colored iron(II) complexes are formed on the sorbents surface during sorption from solutions of pH 2.5 – 5.0 during 20 min. The diffuse reflectance spectra have maxima at 560 and 600 nm for the sorbents with the functional groups of Ferrozine and Ferene S, respectively. This effect was suggested for development of procedures of sorption-photometric and visual test determination of iron(II). The calibration curves were linear over the range 0.1 – 4.0 μg per0,1 gof the sorbent. The limit of detection sorption-photometric determination of iron (II) calculated by the 3s-criterion is 0.006 mg / 0.015 mg and 0.1g / 0.1g for sorbents with functional groups of Ferrozine and Ferene S, respectively. The proposed method was used for determination of total iron in natural waters. The results of sorption-photometric determination of total iron were confirmed by the results of atomic-emission method with inductively coupled plasma.Keywords: Adsorption, modified zirconium oxide, Ferene S, Ferrozine, Iron(II), Diffuse reflectance spectroscopy, test-systems. (Russian)DOI: http://dx.doi.org/10.15826/analitika.2014.18.4.009 S.L. Didukh, A.N. Mukhina, V.N. Losev Research Engineering Centre ‘Kristall’ of Siberian Federal University, Krasnoiarsk, Russian FederationREFERENCES1. Analytical measurements in aquatic environments. Ed. by Namiensnik J., Szefer P. CRC Press, 2010. 503 p.2. Marchenko Z., Bal’tsezhak M. Metody spectrofotometrii v UF i vidimoi oblastiakh v neorganicheskom analize [Spectrophotometric methods in UV and VIS ranges in inorganic analysis]. Moscow, Binom, 2007. 711 p. (in Russian)3. Haghighi B., Safavi A. Simultaneous flow injction determination of iron(II) and iron(III) with opto-electrochemical detection. Anal. Chim. Acta, 1997, vol. 354, pp. 43-50. doi: 10.1016/S0003-2670(97)00436-4.4. Mulaudzi L.V., van Staden J.F., Stefan R.I. On-line determination of iron(II) and iron(III) using a spectrophotometric sequential injection system. Anal. Chim. Acta, 2002, vol. 467, pp. 35-49. doi: 10.1016/S0003-2670(02)00128-9.5. Ermolenko Iu.V., Gridina N.N., Sokolovskaia A.P. [Chemical-analytical system Fe (III) - tyrone - chitosan for spectrophotometry determination of iron]. Uspekhi v khimii i khimicheskoi tekhnologii [Advances in chemistry and chemical technology], 2011, vol. 25, no. 2, pp. 50-55 (in Russian).6. Zhenpu Wang, Cheng K.L. Spectrophotometric Determination of Iron with 1,10-phenanthroline in the Presence of Copper. Microchimica Acta, 1982, II, pp. 115-124. doi: 10.1007/BF012066977. Van Staden J.F., Naidoo E.B. Determination of total iron as Fe(II) in multivitamins, haеmatinics and natural waters using a sequential injection system. South African Journal of Chemistry, 2000, vol. 53, no. 3, pp. 191-205.8. Jankiewicz B., Ptaszynski B., Turek A. Spectrophotometric Determination of Iron(II) in the Soil of Selected Allotment gardens in Lodz. Polish Journal of Environmental Studie, 2002, vol. 11, no. 6, pp. 745-749.9. Fresenius W., Schneider W. For the determination of iron(II) and total iron with 2,2'-dipyridyl in mineral waters. Reduction of iron(III) with ascorbic acid. Z. analyt. Chem, 1976, vol. 209, pp. 340-341.10. Stauffer M.T., Weller W.E., Kubas K.R., Casoni K.A. Limiting reactants in chemical analysis: influences of metals and ligands on calibration curves and formation constants for selected iron-ligand chelates. Stoichiometry and Research – The Impotance of Quantity in Biomedicine, 2012, pp. 311-334.11. Tsurubou S., Sakai T. High-sensitivity extraction - Spectrophotometric determination of iron with 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine and tetrabromophenolphthalein ethyl ester. The Analyst, 1984, vol. 109, pp. 1397-1399. doi: 10.1039/AN9840901397.12. Nagahiro T., Uesugi K., Mehra M.C., Satake M. Spectrophotometric determination of iron(II) after separation by adsorption of its complex with 3-(4-phenyl-2-pyridyl)-5,6-diphenyl-1,2,4-triazine and tetraphenylborate on microcrystalline naphthalene. Talanta, 1985, vol. 31, no. 12, рр. 1112-1114. doi: 10.1016/0039-9140(84)80259-3.13. Ying Chen, Chang-Ming Ding, Tian-Ze Zhou, Da-Yong Qi. Organic solvent-soluble membrane filters for the preconcentration and spectrophotometric determination of iron(II) traces in water with Ferrozine. Fresenius J. Anal. Chem, 1999, vol. 363, рр. 119-120. doi: 10.1007/s002160051152.14. Zolotov Iu.A., Tsizin G.I., Dmitrienko S.G., Morosanova E.I. Sоrbtsiоnnое kоntsеntrirovaniе mikrоkоmpоnеntov iz rаstvоrоv [Sorption concentration of micro components from solutions]. Moscow, Science, 2007. 320 p. (in Russian).15. Lisichkin G.V., Fadeev A.Y., Serdan A.A., Mingalyov P.G., Nesterenko P.N., Furman D.B. Khimiia privitykh pоvеrkhnоstnykh soеdinеnii [Chemistry of Surface Grafted Compounds]. Moscow, Fizmatlit, 2003. 592 p. (in Russian).16. Losev V.N., Didukh S.L., Trofimchuk A.K. [Sorption photometric determination of iron using sorbents on the basis of inorganic oxides having functional groups of 4,7-diphenyl-1,10-phenanthroline]. Izvestiia vyzov. Khimiia i khimicheskaia technologiia [Chemistry and chemical technology], 2009, vol. 52, no. 7, pp. 32-36 (in Russian).17. Shvartsenbach G. Flashka G. Kompleksonometricheskoe titrovanie [Complexometric Titration]. Moscow, Chemistry, 1970. 360 p. (in Russian).18. Rеshetniak Е.А., Kholina Yu.V., Shеvchenko V.N. [The color scales constraction for visual colorimetry. Representation of analysis results]. Меtоdy i оb”еkty khimicheskogo analiza [Methods and objects of chemical analysis], 2011, vol. 6, no 4, pp. 188-197 (in Russian).Получены сорбенты на основе оксида циркония, последовательно модифицированного полигексаметиленгуанидином, феррозином и ференом С. Найдены оптимальные условия модифицирования аминированной поверхности оксида циркония феррозином и ференом С. Сорбционная емкость по отношению к органическим реагентам составляет 25 мкМ/г для феррозина и 5 мкМ/г для ферена С. Синтезированные сорбенты количественно извлекают железо(II) из растворов с рН = 2.5-7.0. При сорбции на поверхности сорбентов образуются интенсивно окрашенные комплексы железа(II), имеющие в спектре диффузного отражения широкую полосу с максимумом при 560 и 600 нм соответственно для сорбентов с функциональными группами феррозина и ферена С. Максимальная интенсивность окраски развивается в течение 20 мин при рН = 2.5-5.0. Образование окрашенных комплексов на поверхности сорбента использовано при разработке методик сорбционно-фотометрического и тест-определения железа(II). Градуировочные графики линейны в диапазоне от 0.1 до 4.0 мкг/0.1 г. Предел обнаружения железа(II) сорбционно-фотометрическим методом, рассчитанный по 3s-критерию, равен 0.006 мкг/0.1 г и 0.015 мкг/0.1 г для сорбентов с функциональными группами феррозина и ферена С, соответственно. Методики использованы при определении общего содержания железа в природных водах. Правильность методик подтверждена атомно-эмиссионным методом с индуктивно связанной плазмой.Ключевые слова: сорбционное концентрирование, модифицированный оксид циркония, феррозин, ферен С, железо(II), сорбционно-фотометрическое определение, тест-системы.DOI: http://dx.doi.org/10.15826/analitika.2014.18.4.009ЛИТЕРАТУРАAnalytical measurements in aquatic environments. Ed. by Namiensnik J., Szefer P. CRC Press, 2010. 503 p.Марченко З., Бальцежак М. Методы спектрофотометрии в УФ и видимой областях в неорганическом анализе: пер. с польского А.В. Гармаша. М.: БИНОМ, 2007. 711 с. Haghighi B., Safavi A. Simultaneous flow injction determination of iron(II) and iron(III) with opto-electrochemical detection // Anal. Chim. Acta. 1997. V. 354. P. 43-50.Mulaudzi L.V. van Staden J.F., Stefan R.I. On-line determination of iron(II) and iron(III) using a spectrophotometric sequential injection system // Anal. Chim. Acta. 2002. V. 467. P. 35-49.Ермоленко Ю.В., Гридина Н.Н., Соколовская А.П. Химико-аналитическая система Fe(III) – тайрон – хитозан в спектрофотометрии железа // Успехи в химии и химической технологии. 2011. Т. 25, № 2. С. 50-55.Zhenpu W., Cheng K.L. Spectrophotometric Determination of Iron with 1,10-phenanthroline in the Presence of Copper // Microchimica Acta. 1982. II. P. 115-124.Van Staden J.F., Naidoo E.B. Determination of total iron as Fe(II) in multivitamins, haеmatinics and natural waters using a sequential injection system // South African Journal of Chemistry. 2000. V. 53, № 3. P. 191-205.Jankiewicz B., Ptaszynski B., Turek A. Spectrophotometric Determination of Iron(II) in the Soil of Selected Allotment gardens in Lodz // Polish Journal of Environmental Studies. 2002. V. 11, № 6. P. 745-749.Fresenius W., Schneider W. For the determination of iron(II) and total iron with 2,2'-dipyridyl in mineral waters. Reduction of iron(III) with ascorbic acid // Z. analyt. Chem. 1976. V. 209. P. 340-341.Limiting reactants in chemical analysis: influences of metals and ligands on calibration curves and formation constants for selected iron-ligand chelates / M. Stauffer [et al.] // Stoichiometry and Research – The Impotance of Quantity in Biomedicine. 2012. P. 311-334.Tsurubou S., Sakai T. High-sensitivity extraction – Spectrophotometric determination of iron with 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine and tetrabromophenolphthalein ethyl ester // The Analyst. 1984. V. 109. P. 1397-1399.Spectrophotometric determination of iron(II) after separation by adsorption of its complex with 3-(4-phenyl-2-pyridyl)-5,6-diphenyl-1,2,4-triazine and tetraphenylborate on microcrystalline naphthalene / T. Nagahiro [et al.] // Talanta. V. 31, № 12. 1985. P. 1112-1114.Organic solvent-soluble membrane filters for the preconcentration and spectrophotometric determination of iron(II) traces in water with Ferrozine / Ying Chen [et al.] // Fresenius J Anal Chem. 1999. V. 363. P. 119-120.Сорбционное концентрирование микрокомпонентов из растворов / Ю.А. Золотов [и др.]. М.: Наука, 2007. 320 с.Химия привитых поверхностных соединений / Г.В. Лисичкин [и др.] М.: Физматлит, 2003. 592 с.Лосев В.Н., Дидух С.Л., Трофимчук А.К. Сорбционно-фотометрическое определение железа с использованием сорбентов на основе неорганических оксидов с функциональными группами 4,7-дифенил-1,10-фенантролина // Известия вузов. Химия и химическая технология. 2009. Т.52, № 7. С. 32-36.Шварценбах Г., Флашка Г. Комплексонометрическое титрование. М.: Химия, 1970. 360 с.Решетняк Е.А., Холина Ю.В., Шевченко В.Н. Построение цветовых шкал для визуальной колориметрии. Представление результатов анализа // Методы и объекты химического анализа. 2011. Т. 6, № 4. С. 188-19
Spatial differences in the distribution of leads in the ice cover in the Atlantic sector of the Arctic basin
Get PDFWe analyzed data on the spatial distribution (density) of large breaks (gaps) in the drifting sea ice cover in the Western Arctic for the period from October 2005 to September 2017, obtained through decoding of lowresolution images from the NOAA satellites. The specific length of gaps, which is the total length of them over an area of 1 km2, is used as a characteristic of the spatial density. It was found that along the continental slope, approximately from the meridian 70° E to the Lincoln Sea, there is a well-defined area of high density, which remains throughout most part of the ice cycle. In this area, the values of the specific gap length averaged over two-month periods exceeded 24 m/km2. In the near-polar region, the density of breaks was smaller throughout the whole ice cycle. The least values of the specific length take place in May–June that is caused by changes in the general state of the ice cover. It was determined that the density of gaps in this area of the Arctic basin well correlated with the speed of wind drift of ice: the more intensive the drift, the larger the density. On the continental slope, two local zones with maximum values of the specific length of breaks reaching 32 m/km2 are considered. It is suggested that the stability of their location in space and time is connected with the increased influence of tidal processes on the deformation of the ice cover over local bottom elevations on the continental slope. A correlation between the bottom profile and the values of the specific length of the gaps along two conditional lines passing through the maximum value zones did show that the largest values of the density are noticed in areas with significant gradients of the depth
Representations of rational Cherednik algebras with minimal support and torus knots
Get PDFIn this paper we obtain several results about representations of rational Cherednik algebras, and discuss their applications. Our first result is the Cohen–Macaulayness property (as modules over the polynomial ring) of Cherednik algebra modules with minimal support. Our second result is an explicit formula for the character of an irreducible minimal support module in type A[subscript n−1] for c=m/n, and an expression of its quasispherical part (i.e., the isotypic part of “hooks”) in terms of the HOMFLY polynomial of a torus knot colored by a Young diagram. We use this formula and the work of Calaque, Enriquez and Etingof to give explicit formulas for the characters of the irreducible equivariant D-modules on the nilpotent cone for SL[subscipt m]. Our third result is the construction of the Koszul–BGG complex for the rational Cherednik algebra, which generalizes the construction of the Koszul–BGG resolution from [3] and [21], and the calculation of its homology in type A. We also show in type A that the differentials in the Koszul–BGG complex are uniquely determined by the condition that they are nonzero homomorphisms of modules over the Cherednik algebra. Finally, our fourth result is the symmetry theorem, which identifies the quasispherical components in the representations with minimal support over the rational Cherednik algebras H[subscript m/n](S[subscript n]) and H[subscript n/m](S[subscript m]). In fact, we show that the simple quotients of the corresponding quasispherical subalgebras are isomorphic as filtered algebras. This symmetry was essentially established in [8] in the spherical case, and in [24] in the case GCD(m,n)=1, and it has a natural interpretation in terms of invariants of torus knots.National Science Foundation (U.S.) (Grant DMS- 1000113
A relationship between rational and multi-soliton solutions of the BKP hierarchy
Get PDFWe consider a special class of solutions of the BKP hierarchy which we call -functions of hypergeometric type. These are series in Schur -functions over partitions, with coefficients parameterised by a function of one variable , where the quantities , , are integrals of motion of the BKP hierarchy. We show that this solution is, at the same time, a infinite soliton solution of a dual BKP hierarchy, where the variables are now related to BKP higher times. In particular, rational solutions of the BKP hierarchy are related to (finite) multi-soliton solution of the dual BKP hierarchy. The momenta of the solitons are given by the parts of partitions in the Schur -function expansion of the -function of hypergeometric type. We also show that the KdV and the NLS soliton -functions coinside the BKP -functions of hypergeometric type, evaluated at special point of BKP higher time; the variables (which are BKP integrals of motions) being related to KdV and NLS higher times
Model studies of THz-range generation by down-conversion in GaSe and GaSeS crystals
Get PDFModel study of not phase matched and phase matched optical rectification or down-conversion of Ti:Sapphire laser pulses at 950 nm into THz and far-IRrange in pure and S-doped GaSe single crystals is carried out. First, the ordinary and extraordinary wave dispersions of the GaSe refractive indices were measured by terahertz time-domain spectroscopy (THz-TDS). Measured data were approximated in the form of Sellmeier dispersion equations for 0.62 - 2000 [mu]m range with using available shorter wave data
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