546 research outputs found
Domain evolution of BaTiO3 ultrathin films under electric field: a first-principles study
A first-principles-derived method is used to study the morphology and
electric-field-induced evolution of stripe nanodomains in (001) BaTiO3 (BTO)
ultrathin films, and to compare them with those in (001) Pb(Zr,Ti)O3 (PZT)
ultrathin films. The BaTiO3 systems exhibit 180o periodic stripe domains at
null electric field, as in PZT ultrathin films. However, the stripes alternate
along [1-10] in BTO systems versus [010] in PZT systems, and no in-plane
surface dipoles occur in BTO ultrathin films (unlike in PZT materials).
Moreover, the evolution of the 180o stripe domains in the BaTiO3 systems, when
applying and increasing an electric field along [001], involves four regions:
Region I for which the magnitude of the down dipoles (i.e., those that are
antiparallel to the electric field) is reduced, while the domain walls do not
move; Region II in which some local down dipoles adjacent to domain walls
switch their direction, resulting in zigzagged domain walls - with the overall
stripe periodicity being unchanged; Region III in which nanobubbles are
created, then contract along [110] and finally collapse; and Region IV which is
associated with a single monodomain. Such evolution differs from that of PZT
ultrathin films for which neither Region I nor zigzagged domain walls exist,
and for which the bubbles contract along [100]. Discussion about such
differences is provided.Comment: 19 pages, 4 figures, 27 references, submitted to Phys. Rev.
Instruments of investment attraction in order to fulfill the structural priorities of sustainable regional development (study based on the Rostov Region)
The aim of the study is devoted to defining most effective tools of investment funds attraction. These funds can be used in implementation of strategic priorities for socio-economic regional development requiring, in areas that are in need of economic restructuring.
The authors have selected the Rostov region as the research target, the economy of which is in need of structural change in the direction of increasing innovational, high-tech and scientific production, in order to reduce import dependency and move closer towards the post-industrial model of economic development.
The study considers currently available instruments of attraction of private sector closer to solving the stated problems of Rostov region, analyzing their regulatory, financial and organizational consulting security on both state and federal level. Main directions of economic restructuring of Rostov region are also defined. Authors also outline the main problems that private enterprises come across while doing business in the investigated area. On the basis of the research, investigating federal and regional instruments of private sector involvement authors form a number of proposals and recommendations focusing on regional improvement. As a result of the conducted study, the authors reached the conclusion, that there is a number of strategic measures that should be performed in the Rostov region. These don't only include the improvement of financial instruments, but also best available technologies, national technology initiative, and clustering.peer-reviewe
Simple Chemical Method for the Determination of Carbon Dioxide in Air
The determination of carbon dioxide in air was always an important practical problem. It became particularly important in recent decades because of the studies of the greenhouse effect Because of difficulties in the direct detection of the equivalence point for the interaction of low concentrations of CO 2 with reagents, the two-step titration method is most frequently used among chemical methods for the determination of CO 2 . Within this method, first an aliquot portion of a solution of barium hydroxide of known concentration is partially neutralized with carbon dioxide contained in a known volume of air, and next residual Ba(OH) 2 is titrated with a reference solution of acid Known instrumental methods In this work, we propose a chemical method for the determination of CO 2 in air, which differs from the method mentioned above by a lower cost and simple implementation, being highly competitive with them in accuracy. The method is based on the detection of the equivalence point in the neutralization of an aqueous solution of Ba(OH) 2 by CO 2 contained in air by measuring the electrical conductance of the solution. The accurate detection of the equivalence point in this case is caused by the fact that CO 2 interacts with Ba(OH) 2 in two reactions proceeding successively [9]: Ç ‡ +2 + 2éç -+ ëé 2 = Ç ‡ëé 3 ↓ + ç 2 é, Ç ‡ëé 3 + ëé 2 + ç 2 é = Ç ‡ 2+ + . From the equations of the reactions, it follows that, at the first step of CO 2 absorption, barium and hydroxyl ions are removed from the solution because of the formation of a barium carbonate precipitate, which leads to a decrease in the electrical conductance of the solu- Abstract -A method was proposed for the direct determination of carbon dioxide in air using a sorption tube specially constructed for this purpose. The method is based on measuring the volume of air consumed for the neutralization of a known amount of barium oxide hydrate in the tube by carbon dioxide contained in air. The equivalence point is detected by the minimum electrical conductance of the barium hydroxide solution. To verify the accuracy of the method, a technique based on the use of a calibration mixture of air with the CO 2 concentration varying by the inverse exponential law was developed. The method is suitable for the determination of CO 2 in air in a wide concentration range and for the verification and calibration of indirect methods for the determination of CO 2 . With an insignificant decrease in accuracy, the equivalence point can be detected by the change in the color of phenolphthalein. This significantly simplifies the method and allows its wide use in practice, e.g., in laboratory works in environmental science or for demonstration purposes in educational organizations
AI MENTORING AS A FORM AKMEOLOGICHESKOJ ORIENTED PROFESSIONAL INTERACTION
Optimization of professional relationships in the "mentor- apprentice" promotes the formation of a professional orientation akmeologicheskoj both subjects interaction. On the one hand , mentoring is one of the oldest and most effective ways to acquire knowledge and skills of young employees of the company in the process of adapting to a new team . On the other - allows teacher to identify their professional and personal opportunities and consciously decide to choose the optimum time of interaction with the students, based on their individual characteristics, as well as improve their own skills.Оптимизация профессиональных взаимоотношений в системе «наставник – ученик» способствует формированию акмеологической профессиональной направленности у обоих субъектов взаимодействия. Наставничество является одним из самых старых и эффективных способов приобретения знаний и навыков молодыми сотрудниками предприятия в процессе их адаптации в новом коллективе; позволяет наставнику выявить свои профессионально-личностные возможности и осознанно определиться в выборе оптимального стажа взаимодействия с учениками, с учетом их индивидуальных особенностей, а также повысить уровень собственного мастерства
ОСОБЛИВОСТІ БІОЦЕНОЗУ ПІХВИ У ЖІНОК ІЗ МІКОПЛАЗМОВОЮ ІНФЕКЦІЄЮ
The aim of the study – to assess the features of the genital biome and the structure of associative forms of vaginal infection in women with mycoplasma infection.
Materials and Methods. 80 women with mycoplasma infection and inflammatory diseases of the genital tract (group I) and 70 women without mycoplasma infection, but with inflammatory diseases of the genital tract (group II) were examined. Microbiological analyzes were carried out and the results were recorded in accordance with order No. 234 of the Ministry of Health of Ukraine dated May 10, 2007. Gardnerellа was diagnosed by the method of bacterioscopy by staining smears according to Romanovsky, followed by taking into account the "key" cells, setting the amine test, and determining the pH. Chlamydia was diagnosed by the luminescent method using the "Chlamy-Scan" kits (Moscow, Russia). The diagnosis of mycoplasmosis was carried out by two methods: the luminescent method using ‘‘Miko-Scan’’ kits (Moscow, Russia) and the culture method using an electrolyte-deficient nutrient agar for the isolation and identification of microorganisms in the urine (Makhachkala, Russia). The results of bacteriological studies were subject to statistical processing using the Student's method.
Results and Discussion. The biome of the vagina was studied in women with mycoplasma infection and inflammatory diseases of the genital tract. It was found that the microecology of the vagina in the examined women is characterized by an imbalance between the normal microflora of Lactobacillus and conditionally pathogenic microflora and the formation of 3–4 component associations of aerobic and anaerobic microorganisms, fungi of Candida in combination with Chlamidya trahomatis. It was found that in women with inflammatory diseases of the genital tract without mycoplasma infection, the vaginal biocenosis differs from the state of microecology of the genital organs of women with mycoplasma infection by a decrease in the frequency of diagnosis of chlamydia and gardnerellosis against the background of an increase in the concentration of opportunistic microflora.
Conclusions. The results of the work indicate the need for bacteriological examination of women for the presence of mycoplasma infection, an in-depth study of the etiology of infectious and inflammatory diseases of the genital organs and the use of adequate methods for the prevention and treatment of vaginal dysbiotic diseases.Цель исследования – изучить особенность биома половых органов и структуру ассоциативных форм инфицирования влагалища у женщин с микоплазменной инфекцией.
Материалы и методы. Обследовано 80 женщин с микоплазменной инфекцией и воспалительными заболеваниями половых путей (I группа) и 70 женщин без микоплазменной инфекции и с воспалительными заболеваниями половых путей (II группа). Проведение микробиологических анализов и учет результатов осуществляли согласно приказу № 234 МОЗ Украины от 10.05.2007 года. Гарднереллез диагностировали методом бактериоскопии путем окрашивания мазков по Романовскому с последующим учетом «ключевых» клеток, постановкой аминового теста, определением рН. Диагностику хламидиоза осуществляли люминесцентным методом с помощью наборов «Хлами-Скан» (Москва, Россия). Диагностику микоплазмоза осуществляли двумя методами: люминесцентным методом, с помощью наборов «Мико-Скан» (Москва, Россия) и культуральным методом с применением электролит-дефицитного питательного агара для выделения и идентификации микроорганизмов в моче (Махачкала, Россия). Результаты бактериологических исследований подлежали статистической обработке по методу Стьюдента.
Результаты исследования и их обсуждение. Установлено, что микроэкология влагалища у обследованных женщин характеризуется дисбалансом между нормальной микрофлорой Lactobacillus и условно-патогенной микрофлорой и формированием 3–4-компонентных ассоциаций аэробных и анаэробных микроорганизмов, грибов р. Candida в сочетании с Chlamydia trahomatis. Установлено, что у пациенток с воспалительными заболеваниями половых путей без микоплазменной инфекции биоценоз влагалища отличается от состояния микроэкологии половых органов женщин с микоплазменной инфекцией снижением частоты диагностики хламидиоза и гарднереллеза на фоне увеличения концентрации условно-патогенной микрофлоры.
Выводы. Результаты работы свидетельствуют о необходимости бактериологического обследования женщин на наличие микоплазменной инфекции, углубленного изучения этиологии инфекционно-воспалительных заболеваний половых органов и применения адекватных методов профилактики и терапии дисбиотических заболеваний влагалища.Мета дослідження – вивчити особливості біому статевих органів та структуру асоціативних форм інфікування піхви у жінок із мікоплазмовою інфекцією.
Матеріали та методи. Обстежено 80 жінок із мікоплазмовою інфекцією та запальними захворюваннями статевих шляхів (І група) та 70 жінок без мікоплазмової інфекції, але із запальними захворюваннями статевих шляхів (ІІ група).
Проведення мікробіологічних досліджень та облік результатів здійснювали відповідно до наказу № 234 МОЗ України від 10.05.2007 року. Гарднерельоз діагностували методом бактеріоскопії шляхом фарбування мазків за Романовським із подальшим урахуванням «ключових» клітин, постановкою амінового тесту та визначенням pН. Діагностику хламідіозу здійснювали люмінесцентним методом за допомогою наборів «Хламі-Скан» (Москва, Росія). Діагностику мікоплазмозу здійснювали двома методами: люмінесцентним методом, за допомогою наборів «Міко-Скан» (Москва, Росія) та культуральним методом із застосуванням електроліт-дефіцитного поживного агару для виділення та ідентифікації мікроорганізмів у сечі (Махачкала, Росія). Результати бактеріологічних досліджень підлягали статистичній обробці за методом Стьюдента.
Результати дослідження та їх обговорення. Встановлено, що мікроекологія піхви в обстежених жінок характеризується дисбалансом між нормальною мікрофлорою Lactobacillus та умовно-патогенною мікрофлорою та формуванням 3–4-компонентних асоціацій аеробних та анаеробних мікроорганізмів, грибів р. Candida в поєднанні з Chlamydia trahomatis. Виявлено, що у пацієнток із запальними захворюваннями статевих шляхів без мікоплазмової інфекції біоценоз піхви відрізняється від стану мікроекології статевих органів жінок із мікоплазмовою інфекцією зниженням частоти діагностики хламідіозу та гарднерельозу на фоні збільшення концентрації умовно-патогенної мікрофлори.
Висновки. Результати роботи свідчать про необхідність бактеріологічного обстеження жінок на наявність мікоплазмової інфекції, поглибленого вивчення етіології інфекційно-запальних захворювань статевих органів та застосування адекватних методів профілактики й терапії дисбіотичних захворювань піхви
Underestimated risks of recurrent long-range ash dispersal from northern Pacific Arc volcanoes
Widespread ash dispersal poses a significant natural hazard to society, particularly in relation to disruption to aviation. Assessing the extent of the threat of far-travelled ash clouds on flight paths is substantially hindered by an incomplete volcanic history and an underestimation of the potential reach of distant eruptive centres. The risk of extensive ash clouds to aviation is thus poorly quantified. New evidence is presented of explosive Late Pleistocene eruptions in the Pacific Arc, currently undocumented in the proximal geological record, which dispersed ash up to 8000?km from source. Twelve microscopic ash deposits or cryptotephra, invisible to the naked eye, discovered within Greenland ice-cores, and ranging in age between 11.1 and 83.7 ka b2k, are compositionally matched to northern Pacific Arc sources including Japan, Kamchatka, Cascades and Alaska. Only two cryptotephra deposits are correlated to known high-magnitude eruptions (Towada-H, Japan, ca 15 ka BP and Mount St Helens Set M, ca 28 ka BP). For the remaining 10 deposits, there is no evidence of age- and compositionally-equivalent eruptive events in regional volcanic stratigraphies. This highlights the inherent problem of under-reporting eruptions and the dangers of underestimating the long-term risk of widespread ash dispersal for trans-Pacific and trans-Atlantic flight route
Development of Intelligent Interface to Input and Edit Meteorological Data
The paper presents the method of development of user interface for the hydrometeorological data acquisition system. This research includes some basic principles of creating hydrometeorological messages according to code KN-01 SYNOP. This code allows creating messages as a set of code groups. Every group keeps values of definite meteorological properties. The result of studies was implemented in creating of the user interface for the software that allows working with hydrometeorological data. The KN-01 code defines the class hierarchy of this software. The studies have shown that this method of software development is especially effective for visualization of the meteorological telegrams on devices with small display
Studying the expression of productivity and immunity genes of chickens under the influence of feed glyphosate using the RNA-seq method
The aim of the study was to study the effect of different concentrations of glyphosate on meat productivity and differential expression of genes for immunity and broiler productivity. Broilers were divided into groups: Control I, who received a diet without the introduction of glyphosate, Experimental II, who received a diet with the addition of glyphosate at a dose of 10 mg/kg of feed (0.5 MPC for food); Experimental III, who received a diet with the addition of glyphosate at a dose of 20 mg/kg of feed (1 MPC); Experimental IV, who received a diet with the addition of glyphosate at a dose of 100 mg/kg of feed (5 MPC). Transcriptome analysis was performed by RNA-seq on the Illumina Miseq platform, using the TruSeq Stranded mRNA kit (Illumina, USA). In the 22-28-day period of broiler rearing, a decrease in live weight gain (83 g less) was observed in Experimental group III compared to Control I (P≤0.05). It has been shown that glyphosate at the level of 1 and 5 MPC for food causes activation (P≤0.05) of the proinflammatory response genes (IL15, IL1B, IL34, IL22) and apoptosis (Casp1, Casp2, Casp6, Casp7, Casp8, Casp9) up to 31.1 times, which probably leads to the redistribution of nutrients in in the body towards the immune system, reducing the functions of absorption in the intestine. In parallel, there is an inhibition (P≤0.05) of the expression of genes that have a direct effect on growth and development, which ultimately leads to a decrease in poultry meat productivity. Exposure to glyphosate is an important but unaccounted-for risk factor for reducing meat productivity in birds, acting through a change in gene expression
Atomistic simulations of self-trapped exciton formation in silicon nanostructures: The transition from quantum dots to nanowires
Using an approximate time-dependent density functional theory method, we
calculate the absorption and luminescence spectra for hydrogen passivated
silicon nanoscale structures with large aspect ratio. The effect of electron
confinement in axial and radial directions is systematically investigated.
Excited state relaxation leads to significant Stokes shifts for short nanorods
with lengths less than 2 nm, but has little effect on the luminescence
intensity. The formation of self-trapped excitons is likewise observed for
short nanostructures only; longer wires exhibit fully delocalized excitons with
neglible geometrical distortion at the excited state minimum.Comment: 10 pages, 4 figure
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