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Computational Chemistry 2018年第4期6卷 87-112页

作者： Nyanda Madili Alexander Pogrebnoi tatiana pogrebnaya Department of Materials Energy Science and Engineering The Nelson Mandela African Institution of Science and Technology Arusha Tanzania

The dye sensitized solar cells (DSSCs) have been extensively studied due to their low production cost and simple fabrication process. Dye co-sensitization broadens the absorption spectrum of the sensitizer;thus enhances light harvesting efficiency;and contributes to the improvement of the DSSCs overall efficiency. In this study we performed theoretical design of complex molecule (C45H32N2O4) through combination (esterification reaction) of the natural dye lawsone and synthetic metal free indoline dye D131. The excitation energies, vibration spectra, molecular structures, electronic absorption spectra and electron transitions in individual dyes and complex molecule were investigated using density functional theory (DFT) and time dependent density functional theory (TD-DFT) B3LYP5 methods, with 3-21G, 6-31G and 6-31G(d,p) basis sets. The UV-Vis absorption spectra of the individual dyes and their mixture in chloroform solution were measured using spectrophotometer. For the complex formation reaction, enthalpy, entropy and Gibbs free energy were calculated and the results indicated the reaction was endothermic and non-spontaneous. Electron density distribution of the frontier and adjacent molecular orbitals and energy levels alignment were used for analysis of the electronic spectra and mechanism of transitions. The results indicated that the designed complex molecule satisfied the requirements for good photosensitizer of DSSCs.

关键词： DSSCs Lawsone Indoline D131 Molecular Design IR Spectra UV-Vis Spectra DFT TD-DFT

Oldoinyo Lengai Volcanic Ash for Removal of Hydrogen Sulfide and Ammonia from Biogas

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Journal of Materials Science and Chemical Engineering 2018年第4期6卷 78-93页

作者： Isack Kandola Alexander Pogrebnoi tatiana pogrebnaya Department of Materials Energy Science and Engineering The Nelson Mandela African Institution of Science and Technology Arusha Tanzania

Oldoinyo Lengai mountain located in Northern Tanzania is the only active natrocarbonatite volcano with unusually alkali-rich natrocarbonatites which are not found elsewhere in the world. Volcanic ash formed earlier during eruptions was collected from different sites along the mountain, and its potency to adsorb hydrogen sulfide (H2S) and ammonia (NH3) from biogas was investigated. The samples were calcinated at different temperatures (550℃ - 850℃) and were characterized by X-ray florescent, scanning electron microscopy and X-ray diffraction techniques. The on-site adsorption experiments were conducted at the biogas digester at ambient conditions. The calcinated ash was packed into the reactor bed, biogas allowed to pass through the adsorbent, and the inlet and outlet concentrations of H2S and NH3 were measured. The height of the site where the adsorbent was taken from, calcination temperature, biogas flowrate and mass of the adsorbent were variable parameters and found to influence greatly on the efficiency of H2S and NH3 removal. The efficiency is increased with calcination temperature raise and mass of adsorbent and decreased with flowrate increase. The samples collected from the top site of the mountain and calcinated at 850℃ exhibited the best sorption performance.

关键词： Adsorption Calcination Flowrate Oldoinyo Lengai Volcanic Ash H2S and NH3 Removal

Features of the monocyte inflammatory response in patients with premature coronary artery disease

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Biophysics Reports 2025年第01期11卷 12-17页

作者： tatiana Blokhina tatiana Kirichenko Yuliya Markina Ulyana Khovantseva Ivan Melnikov Olga Guseva Sergey Bazanovich Sergey Kozlov Alexander Orekhov Department of problems of atherosclerosis Chazov National Medical Research Center of Cardiology of the Ministry of Health of the Russian Federation Laboratory of medical genetics Chazov National Medical Research Center of Cardiology of the Ministry of Health of the Russian Federation Laboratory of cellular and molecular pathology of cardiovascular system State Scientific Center of the Russian Federation Petrovsky National Research Center of Surgery Laboratory of cell hemostasis Chazov National Medical Research Center of Cardiology of the Ministry of Health of the Russian Federation Laboratory of Gas Exchange Biomechanics and Barophysiology State Scientific Center of the Russian FederationThe Institute of Biomedical Problems of the Russian Academy of Sciences Laboratory of stem cells Chazov National Medical Research Center of Cardiology of the Ministry of Health of the Russian Federation

The purpose of this study was to examine the secretion of inflammatory cytokines by cultured monocytes/macrophages in patients with premature coronary artery disease(CAD). The study included 38patients with premature CAD and 35 patients without CAD. A primary culture of CD14+ monocytes was obtained by immunomagnetic separation. The inflammatory response was induced by incubation of a cell culture with lipopolysaccharide(LPS) for 24 hours on Days 1 and 6. Basal and LPS-stimulated secretion of the cytokines, tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β), interleukin-6(IL-6),interleukin-8(IL-8) and monocyte chemotactic protein-1(MCP-1) was assessed by enzyme immunoassay on Days 2 and 7 of cultivation. The level of basal secretion of TNF-α, IL-1β, IL-6, MCP-1 was higher in patients with CAD compared to patients in the control group. The levels of re-stimulated TNF-α secretion and the levels of LPS-stimulated and re-stimulated IL-1β secretion on the second and sixth days were also higher in patients with CAD. LPS-stimulated MCP-1 secretion on the second day did not differ in patients of both groups, but re-stimulated MCP-1 secretion was higher in patients with CAD. The results of logistic regression analysis showed that the basal secretion levels of IL-1β and IL-6 were independently associated with premature CAD, along with smoking, body mass index and serum HDLcholesterol levels.

关键词： Coronary artery disease Monocytes Inflammatory cytokines Immune tolerance

Using Transgenic Entomopathogenic Fungi to Prevent Dengue Fever: Current Status, Challenges and Perspectives

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Advances in Entomology 2025年第1期13卷 48-60页

作者： Etienne M. Bilgo Houeffa Adeline tatiana Dokpomiwa Abdoulaye Diabate Biomedical and Public Health Department Institute of Research in Health Sciences (IRSS) Western Regional Directorate Bobo-Dioulasso Burkina Faso Muraz Center National Institute of Public Health (INSP) Bobo Dioulasso Burkina Faso Rural Development Institute (IDR) Nazi Boni University (UNB) Bobo Dioulasso Burkina Faso

Over the last few decades, dengue fever epidemics have increased in frequency and intensity worldwide, making it a major global concern for public health. Its prevention, which is essentially vector-based control, is already being compromised by reports of resistance of the main vector Aedes aegypti to insecticides. To tackle the rapid increase in insecticide resistance and outbreaks, the biological vector control is a promising approach. One of the strategies of this approach is the use of entomopathogenic fungi because of their great efficacy and their eco-friendly aspects. However, some aspects of their use, such as the low efficiency, the high cost of production and the sensitivity to various adverse conditions, need to be addressed for their successful large-scale application. Therefore, innovative technologies based on strains of transgenic fungi with improved biocontrol potentials by genetic engineering are actively pursued. Although these modified mycoinsecticides are acclaimed for their better effectiveness against target insects, the main concern remains their potential adverse effects on the environment and human health. The present review is dedicated to giving an update on recent developments in transgenic entomopathogenic fungi (TEF) for Aedes mosquito control. Future perspectives are also proposed to address the safety concerns related to the release of transgenic entomopathogenic fungi into the environment.

关键词： Transgenic Entomopathogenic Fungi Dengue Control

Homogenization of Linear Parabolic Equations with a Certain Resonant Matching Between Rapid Spatial and Temporal Oscillations in Periodically Perforated Domains

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Acta Mathematicae Applicatae Sinica 2019年第2期35卷 340-358页

作者： tatiana LOBKOVA Department of Mathematics and Science Education Mid Sweden University

In this article, we study homogenization of a parabolic linear problem governed by a coefficient matrix with rapid spatial and temporal oscillations in periodically perforated domains with homogeneous Neumann data on the boundary of the holes. We prove results adapted to the problem for characterization of multiscale limits for gradients and very weak multiscale convergence.

关键词： Homogenization two-scale convergence multiscale convergence periodically perforated domains

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Role of social and individual experience in interaction of the meadow ant Formica pratensis （Hymenoptera： Formicidae） with ladybird imagines and hoverfly larvae

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Insect Science 2015年第3期22卷 440-450页

作者： tatiana A. Novgorodova Institute of Systematics and Ecology of Animals Siberian Branch of the Russian Academy of Sciences Frunze str. 11 Novosibirsk 630091 Russia

The ability to recognize aphidophages is one of the key points in the protection ants provide aphids against their natural enemies. Behavior of honeydew collectors from nature （＂field,＂ control） and laboratory reared ＂naive＂ ants of Formica pratensis Retzius, which had never met either ＂mature＂ workers or aphids and aphidophages, was observed during their pairwise interactions with ladybird imagines and hoverfly larvae. The majority of the ＂naive＂ ants perceived ladybirds as an enemy at their first encounter attacking them immediately without any prior antennation. Ants seem to have a certain innate ＂enemy image＂ that lets them react very quickly to protect aphids. Hoverfly larvae were rarely attacked by both ＂field＂ and ＂naive＂ ants （〉 15%）. During tests with ladybirds ants from nature attacked them and also demonstrated the most aggressive reactions （series of bites and ＂death grip＂） less frequently than the ＂naive＂ ants. The percentage of ants avoiding aphidophages after a contact with their chemical defense （reflex bleeding and glue-like saliva） was significantly higher in the control group. Whereas the ＂naive＂ ants did not learn to avoid danger, foragers from nature usually tried to avoid negative experience and used tactics of ＂short bites.＂ Overall, experience has been proved to be unimportant for displaying key behavioral reactions underlying ant-ladybird interaction. However, accumulation of experience has been assumed to play an important role in the formation of behavioral strategy that allows honeydew collectors to drive aphidophages away with lower energy costs and avoid or minimize negative consequences of aphidophages＇ chemical defense.

关键词： ants aphidophages defense enemy recognition Harmonia axyridis Meligramma triangulifera

Influence of atmospheric circulation on precipitation in Altai Mountains

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Journal of Mountain Science 2017年第1期14卷 46-59页

作者： MALYGINA Natalia PAPINA tatiana KONONOVA Nina BARLYAEVA tatiana Institute for Water and Environmental Problems Siberian Branch of the Russian Academy of SciencesBarnaul 656038Russia Institute of Geography Russian Academy of SciencesMoscow 117312Russia Laboratoire d'Astrophysique de Marseille UMR 7326 CNRS-INSUMarseille13388France

We analyzed the changes in precipitation regime in the Altai Mountains for 1959-2014 and estimate the influence of atmospheric circulations on these changes. Our study showed that during last 56 years the changes in the precipitation regime had a positive trend for the warm seasons(April-October),but weakly positive or negative trends for the cold seasons(November-March). It was found that these changes correspond to the decreasing contribution of "Northern meridional and Stationary anticyclone(Nm-Sa)" and "Northern meridional and East zonal(Nm-Ez)" circulation groups and to the increasing contribution of "West zonal and Southern meridional(Wz-Sm)" circulation groups,accordingly to the Dzerdzeevskii classification. In addition,it was found that the variation of precipitation has a step change point in 1980. For the warm seasons,the precipitation change at this point is associated with the reduced influence of "West zonal(Wz)","Northern meridional and Stationary anticyclone(Nm-Sa)" and "Northern meridional and Southern meridional(Nm-Sm)" circulation groups. For the cold seasons,a substantialincrease of "Wz-Sm" and a decrease of "Nm-Sa","Nm-Ez" circulation groups are responsible for the precipitation change in the two time periods(1959-1980 and 1981-2014).

关键词： Altai Mountains Precipitation Atmospheric circulation

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Effects of long-term medieval agriculture on soil properties:A case study from the Kislovodsk basin,Northern Caucasus,Russia

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Journal of Mountain Science 2018年第6期15卷 1171-1185页

作者： CHERNYSHEVA Elena KHOMUTOVA tatiana FORNASIER Flavio KUZNETSOVA tatiana BORISOV Alexandr Institute of Physicochemical and Biological Problems in Soil Science Russian Academy of Sciences Institutskaya 14229o Pushchino Moscow region Russia 2 CREA - VE Consiglio per la ricerca in Agricoltura e rAnalisi della Economia Agraria Centro di Ricerea Viticoltura ed Enologia Via Trieste 23 34170 Gorizia Italy

The chemical properties and biological activities of soils were studied in the vicinity of the medieval settlement Podkumskoe-3 in the Kislovodsk basin(Northern Caucasus, Russia). Between the 5 th and 8 th centuries this area was ploughed regularly, but it was then abandoned up to the present day. It has been established that past human activity leads to soil undergoing significant transformations in terms of microbial communities and enzyme activity, and that such changes are maintained over long periods. Long-term manuring in the middle of the first millennium AD led to an increase in organic carbon content and the accumulation of nitrate nitrogen. Soils of ancient abandoned fields are associated with increases in microbial biomass, number of saprotrophic bacteria, urease activity, and fungal mycelium biomass. The observed changes in the microbiological and biochemical properties of soil were conditioned by secondary anthropogenically induced succession after the abandonment of arable lands.

关键词： Anthropogenic soils Manuring Enzymeactivity Microbial biomass North Caucasus MiddleAges

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ON AUGMENTED LAGRANGIAN METHODS FOR SADDLE-POINT LINEAR SYSTEMS WITH SINGULAR OR SEMIDEFINITE （1, 1） BLOCKS

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Journal of Computational Mathematics 2014年第3期32卷 297-305页

作者： tatiana S. Martynova Computing Center Southern Federal University Rostov-on-Don Russia

An effective algorithm for solving large saddle-point linear systems, presented by Krukier et al., is applied to the constrained optimization problems. This method is a modification of skew-Hermitian triangular splitting iteration methods. We consider the saddle-point linear systems with singular or semidefinite （1, 1） blocks. Moreover, this method is applied to precondition the GMRES. Numerical results have confirmed the effectiveness of the method and showed that the new method can produce high-quality preconditioners for the Krylov subspace methods for solving large sparse saddle-point linear systems.

关键词： Hermitian and skew-Hermitian splitting Saddle-point linear system Constrained optimization Krylov subspace method.

General techniques for constructing variational integrators

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Frontiers of Mathematics in China 2012年第2期7卷 273-303页

作者： Melvin LEOK tatiana SHINGEL Department of Mathematics University of California San Diego La Jolla CA 92093 USA

The numerical analysis of variational integrators relies on variational error analysis, which relates the order of accuracy of a variational integrator with the order of approximation of the exact discrete Lagrangian by a computable discrete Lagrangian. The exact discrete Lagrangian can either be characterized variationally, or in terms of Jacobi＇s solution of the Hamilton- Jacobi equation. These two characterizations lead to the Galerkin and shooting constructions for discrete Lagrangians, which depend on a choice of a numerical quadrature formula, together with either a finite-dimensional function space or a one-step method. We prove that the properties of the quadrature formula, finite-dimensional function space, and underlying one-step method determine the order of accuracy and momentum-conservation properties of the associated variational integrators We also illustrate these systematic methods for constructing variational integrators with numerical examples.

关键词： Geometric numerical integration geometric mechanics symplectic integrator variational integrator Lagrangian mechanics