197 research outputs found
УПРОЩЕННЫЙ МЕТОД АНАЛИЗА, КОНТРОЛЯ И ПРОГНОЗА ВЫСОКОГО ЗАГРЯЗНЕНИЯ ВОДЫ ОТДЕЛЬНЫМИ КОМПОНЕНТАМИ
Assessing the risks and predicting the increased pollution of natural water bodies is especially important in the industrial regions where the instability of the monitored indicators is most significant. This article proposes methods of this activity with the use of non-parametric and more accurate parametric methods of hydro-monitoring data analysis. The results of using these methods for the Ural region have been obtained, and it has been shown that the analytical description of the "tail" parts of the probability distribution in the studied water quality indicators with the use of the Pareto distribution allows to identify the appropriate indicators for the limited volume samples and to give the projected estimates in the unobserved parts of the distributions. It has been noted that the risk of significant water pollution exists even if the situation is relatively favorable according to the hydro-monitoring. In this regard, a methodology of estimating the upper limit of the confidence interval covering the value of the monitored index with the acceptable reliability has been proposed. Practical examples show the effectiveness of this method. The special significance of the application of the proposed approaches to the predicting aspect is due to the possibility of assessing the small risks of the appearance of extreme unit values of the investigated random variables.Keywords: probability of considerable water contamination, prediction, the «tail» of the probability distribution function, ranking the highest concentrations, upper fiducial limit, the theory of order statistics.DOI: http://dx.doi.org/10.15826/analitika.2017.21.2.008 O.M. Rosental’1, L.N. Aleksandrovskaya2, A.V. Kirillin2 1Institute of Water Problems of RAS, Gubkin ul., 3, Moscow, 119991, Russian Federation 2Moscow aviation Institute, Volokolamskoe shosse, 4, Moscow, 125993, Russian FederationОценка риска и прогноз повышенного загрязнения природных вод особенно важны в промышленных регионах, где нестабильность контролируемых показателей наиболее высока. Поскольку риск является вероятностной характеристикой степени загрязнения воды отдельными компонентами, для решения этой задачи необходимо привлечение статистических методов. В статье предложена практическая методика такой оценки с использованием непараметрических, основанных на теории порядковых статистик, и более точных параметрических методов статистического анализа данных гидромониторинга, требующих аналитического описания функции распределения концентрации загрязняющих веществ. Результаты использования методики апробированы для уральского региона, для чего обосновано и показано, что аналитическое описание «хвостовых» частей функций распределения вероятностей при больших значениях исследуемых показателей качества воды распределением Парето позволяет по выборкам ограниченного объема определять соответствующие показатели в ненаблюдаемых частях распределений, т.е. давать прогнозные оценки. Отмечено, что риск высокого загрязнения воды существует, даже если ситуация по данным гидромониторинга относительно благополучна. В связи с этим предложена методика оценки доверительного интервала, покрывающего значения контролируемого показателя с заданной доверительной вероятностью, в том числе наиболее важной его верхней доверительной границы. На практических демонстрационных примерах показана эффективность разработанной методики. Особая значимость применения предложенных подходов к прогнозной задаче обусловлена возможностью оценивания малых рисков появления экстремальных единичных значений исследуемых случайных величин.Ключевые слова: вероятность высокого загрязнения воды, прогноз, «хвост» функции распределения вероятностей, ранжирование наибольших значений концентрации, верхняя граница доверительного интервала, теория порядковых статистикDOI: http://dx.doi.org/10.15826/analitika.2017.21.2.00
Branching ratio change in K- absorption at rest and the nature of the Lambda(1405)
We investigate in-medium corrections to the branching ratio in K- absorption
at rest and their effect on the (positively and negatively) charged pion
spectrum. The in-medium corrections are due to Pauli blocking, which arises if
the Lambda(1405) is assumed to be a -nucleon bound state and leads to
a density and momentum dependent mass shift of the Lambda(1405). Requiring that
the optical potential as well as the branching ratio are derived from the same
elementary T-matrix, we find that the in-medium corrected, density dependent
T-matrix gives a better description of the K- absorption reaction than the
free, density-independent one. This result suggests that the dominant component
of the Lambda(1405) wave function is the bound state.Comment: 8 Pages, Revtex with epsf, and embedded 8 ps figure
Heterologous reporter expression in the planarian Schmidtea mediterranea through somatic mRNA transfection
Planarians have long been studied for their regenerative abilities. Moving forward, tools for ectopic expression of non-native proteins will be of substantial value. Using a luminescent reporter to overcome the strong autofluorescence of planarian tissues, we demonstrate heterologous protein expression in planarian cells and live animals. Our approach is based on the introduction of mRNA through several nanotechnological and chemical transfection methods. We improve reporter expression by altering untranslated region (UTR) sequences and codon bias, facilitating the measurement of expression kinetics in both isolated cells and whole planarians using luminescence imaging. We also examine protein expression as a function of variations in the UTRs of delivered mRNA, demonstrating a framework to investigate gene regulation at the post-transcriptional level. Together, these advances expand the toolbox for the mechanistic analysis of planarian biology and establish a foundation for the development and expansion of transgenic techniques in this unique model system
Hyperfine structure of EPR spectra of Gd3+ odd isotopes in PbMoO4, Pb5Ge3O11, YVO4, and quadrupole interaction (temperature dependence)
Simplified method of analysis, control and forecast of high water pollution by separate components
Assessing the risks and predicting the increased pollution of natural water bodies is especially important in the industrial regions where the instability of the monitored indicators is most significant. This article proposes methods of this activity with the use of non-parametric and more accurate parametric methods of hydro-monitoring data analysis. The results of using these methods for the Ural region have been obtained, and it has been shown that the analytical description of the “tail” parts of the probability distribution in the studied water quality indicators with the use of the Pareto distribution allows to identify the appropriate indicators for the limited volume samples and to give the projected estimates in the unobserved parts of the distributions. It has been noted that the risk of significant water pollution exists even if the situation is relatively favorable according to the hydro-monitoring. In this regard, a methodology of estimating the upper limit of the confidence interval covering the value of the monitored index with the acceptable reliability has been proposed. Practical examples show the effectiveness of this method. The special significance of the application of the proposed approaches to the predicting aspect is due to the possibility of assessing the small risks of the appearance of extreme unit values of the investigated random variables.Оценка риска и прогноз повышенного загрязнения природных вод особенно важны в промышленных регионах, где нестабильность контролируемых показателей наиболее высока. Поскольку риск является вероятностной характеристикой степени загрязнения воды отдельными компонентами, для решения этой задачи необходимо привлечение статистических методов. В статье предложена практическая методика такой оценки с использованием непараметрических, основанных на теории порядковых статистик, и более точных параметрических методов статистического анализа данных гидромониторинга, требующих аналитического описания функции распределения концентрации загрязняющих веществ. Результаты использования методики апробированы для уральского региона, для чего обосновано и показано, что аналитическое описание «хвостовых» частей функций распределения вероятностей при больших значениях исследуемых показателей качества воды распределением Парето позволяет по выборкам ограниченного объема определять соответствующие показатели в ненаблюдаемых частях распределений, т.е. давать прогнозные оценки. Отмечено, что риск высокого загрязнения воды существует, даже если ситуация по данным гидромониторинга относительно благополучна. В связи с этим предложена методика оценки доверительного интервала, покрывающего значения контролируемого показателя с заданной доверительной вероятностью, в том числе наиболее важной его верхней доверительной границы. На практических демонстрационных примерах показана эффективность разработанной методики. Особая значимость применения предложенных подходов к прогнозной задаче обусловлена возможностью оценивания малых рисков появления экстремальных единичных значений исследуемых случайных величин
O ensino da tabuada no contexto das ações de estudo propostas por Davýdov e colaboradores
Fish community modeling agents on an artificial reef on the northern coast of Rio de Janeiro - Brazil
Position of the Third Na+ Site in the Aspartate Transporter GltPh and the Human Glutamate Transporter, EAAT1
Glutamate transport via the human excitatory amino acid transporters is coupled to the co-transport of three Na+ ions, one H+ and the counter-transport of one K+ ion. Transport by an archaeal homologue of the human glutamate transporters, GltPh, whose three dimensional structure is known is also coupled to three Na+ ions but only two Na+ ion binding sites have been observed in the crystal structure of GltPh. In order to fully utilize the GltPh structure in functional studies of the human glutamate transporters, it is essential to understand the transport mechanism of GltPh and accurately determine the number and location of Na+ ions coupled to transport. Several sites have been proposed for the binding of a third Na+ ion from electrostatic calculations and molecular dynamics simulations. In this study, we have performed detailed free energy simulations for GltPh and reveal a new site for the third Na+ ion involving the side chains of Threonine 92, Serine 93, Asparagine 310, Aspartate 312, and the backbone of Tyrosine 89. We have also studied the transport properties of alanine mutants of the coordinating residues Threonine 92 and Serine 93 in GltPh, and the corresponding residues in a human glutamate transporter, EAAT1. The mutant transporters have reduced affinity for Na+ compared to their wild type counterparts. These results confirm that Threonine 92 and Serine 93 are involved in the coordination of the third Na+ ion in GltPh and EAAT1
Glycans in Sera of Amyotrophic Lateral Sclerosis Patients and Their Role in Killing Neuronal Cells
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease caused by degeneration of upper and lower motor neurons. To date, glycosylation patterns of glycoproteins in fluids of ALS patients have not been described. Moreover, the aberrant glycosylation related to the pathogenesis of other neurodegenerative diseases encouraged us to explore the glycome of ALS patient sera. We found high levels of sialylated glycans and low levels of core fucosylated glycans in serum-derived N-glycans of patients with ALS, compared to healthy volunteer sera. Based on these results, we analyzed the IgG Fc N297-glycans, as IgG are major serum glycoproteins affected by sialylation or core fucosylation and are found in the motor cortex of ALS patients. The analyses revealed a distinct glycan, A2BG2, in IgG derived from ALS patient sera (ALS-IgG). This glycan increases the affinity of IgG to CD16 on effector cells, consequently enhancing Antibody-Dependent Cellular Cytotoxicity (ADCC). Therefore, we explore whether the Fc-N297-glycans of IgG may be involved in ALS disease. Immunostaining of brain and spinal cord tissues revealed over-expression of CD16 and co-localization of intact ALS-IgG with CD16 and in brain with activated microglia of G93A-SOD1 mice. Intact ALS-IgG enhanced effector cell activation and ADCC reaction in comparison to sugar-depleted or control IgG. ALS-IgG were localized in the synapse between brain microglia and neurons of G93A-SOD1 mice, manifesting a promising in vivo ADCC reaction. Therefore, glycans of ALS-IgG may serve as a biomarker for the disease and may be involved in neuronal damage
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