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Saenko Y.V.,Technological Institute | Rastorgueva E.V.,Ulyanovsk State University | Maslakova A.G.,Ulyanovsk State University
Bulletin of Experimental Biology and Medicine | Year: 2013

Radiation-induced accumulation of active oxygen species and the role of the mitochondria in this process were studied on cultured K562 leukemia cells. Intracellular concentrations of active oxygen species in the presence of rotenone and without it and the mitochondrial potential were analyzed 15, 30 min, 1, 4, 8, 12, 24, and 48 h after X-ray exposure in doses of 4 and 12 Gy. Radiation-induced generation of active oxygen species had two time peaks: 30 min and 24 h after the exposure. Addition of rotenone reduced the levels of active oxygen species 24 and 48 h after the exposure. Increase of active oxygen species concentrations was paralleled by an increase of the mitochondrial potential. The mitochondria were responsible for the increase in the concentrations of active oxygen species 12-48 h after irradiation. © 2013 Springer Science+Business Media New York.


News Article | December 8, 2016
Site: phys.org

Electron microscopy of a manganese dioxide nanowire in cross-section shows its tunnelled atomic structure, stabilized by potassium ions. The tunnels measure about three-quarters of a nanometer, or 7.5 ångstroms, in diameter. The inset is a model of the tunnel viewed down its axis. Credit: Reza Shahbazian-Yassar/UIC Battery researchers seeking improved electrode materials have focused on "tunneled" structures that make it easier for charge-carrying ions to move in and out of the electrode. Now a team led by a researcher at the University of Illinois at Chicago has used a special electron microscope with atomic-level resolution to show that certain large ions can hold the tunnels open so that the charge-carrying ions can enter and exit the electrode easily and quickly. The finding is reported in Nature Communications. "Significant research has been done to increase the energy density and power density of lithium ion battery systems," says Reza Shahbazian-Yassar, associate professor of mechanical and industrial engineering at UIC. The current generation, he said, is useful enough for portable devices, but the maximum energy and power that can be extracted is limiting. "So for an electric car, we need to increase the energy and power of the battery—and decrease the cost as well," he said. His team, which includes coworkers at Argonne National Laboratory, Michigan Technological Institute and the University of Bath in the U.K., has focused on developing a cathode based on manganese dioxide, a very low cost and environmentally-friendly material with high storage capacity. Manganese dioxide has a lattice structure with regularly spaced tunnels that allow charge carriers—like lithium ions—to move in and out freely. "But for the tunnels to survive for long-lasting function, they need support structures at the atomic scale," Shahbazian-Yassar said. "We call them tunnel stabilizers, and they are generally big, positive ions, like potassium or barium." But the tunnel stabilizers, being positively charged like the lithium ions, should repel each other. "If lithium goes in, will the tunnel stabilizer come out?" Shahbazian-Yassar shrugged. "The research community was in disagreement about the role of tunnel stabilizers during the transfer of lithium into tunnels. Does it help, or hurt?" The new study represents the first use of electron microscopy to visualize the atomic structure of tunnels in a one-dimensional electrode material—which the researchers say had not previously been possible due to the difficulty of preparing samples. It took them two years to establish the procedure to look for tunnels in potassium-doped nanowires of manganese dioxide down to the single-atom level. Yifei Yuan, a postdoctoral researcher working jointly at Argonne National Laboratory and UIC and the lead author on the study, was then able to use a powerful technique called aberration-corrected scanning transmission electron microscopy to image the tunnels at sub-ångstrom resolution so he could clearly see inside them—and he saw they do change in the presence of a stabilizer ion. "It's a direct way to see the tunnels," Yuan said. "And we saw that when you add a tunnel stabilizer, the tunnels expand, their electronic structures also change, and such changes allow the lithium ions to move in and out, around the stabilizer." The finding shows that tunnel stabilizers can help in the transfer of ions into tunnels and the rate of charge and discharge, Shahbazian-Yassar said. The presence of potassium ions in the tunnels improves the electronic conductivity of manganese dioxide and the ability of lithium ions to diffuse quickly in and out of the nanowires. "With potassium ions staying in the center of the tunnels, the capacity retention improves by half under high cycling current, which means the battery can hold on to its capacity for a longer time," he said. Explore further: Better than perfect: Defects in materials could be key to better batteries More information: Yifei Yuan et al, The influence of large cations on the electrochemical properties of tunnel-structured metal oxides, Nature Communications (2016). DOI: 10.1038/ncomms13374


Karanikola M.N.K.,Cyprus University of Technology | Papathanassoglou E.D.E.,Cyprus University of Technology | Mpouzika M.,Technological Institute | Lemonidou C.,National and Kapodistrian University of Athens
Dimensions of Critical Care Nursing | Year: 2012

Burnout symptoms in Greek intensive care unit (ICU) nurses have not been explored adequately. The aim of this descriptive, correlational study was to investigate the prevalence and intensity of burnout symptoms in Greek ICU nursing personnel and any potential associations with professional satisfaction, as well as with demographic, educational, and vocational characteristics. Findings showed that the overall burnout level reported by Greek ICU nursing personnel was at a moderate to high degree. The most pronounced symptom of burnout was depersonalization, whereas emotional exhaustion was found to be a strong predictor of job satisfaction. This is a factor connected with the nurses' intention to quit the job. It appears that work factors have a more powerful influence over the development of burnout in comparison to personality traits. Copyright © 2012 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.


News Article | November 23, 2016
Site: www.eurekalert.org

Margarita Romanets, RUDN 1st year graduate student (Agronomy) presented her invention - intensive block aqua plantation for strawberries at ?II International salon of inventions and new technologies. The invention is being tested at RUDN Agrarian-Technological Institute green house. Strawberry runners grow in water unlike the usual method of putting them in soil. When the runners get on the soil covered with special film, the growing roots cannot implant on the film, dry down and later get damaged and attacked by insects The water plantation allows growing plants with strong roots immune to diseases. The plants that appear on strawberry runners are ready to be planted in open soil and bring good harvest during 4-5 years. The experiment is supervised by ass.prof.Sergey Kornatsky, PhD. The project was also awarded with Diploma of the RF Fundamental sciences Foundation and Kazakh National Agrarian University Rector's Cup. II International salon of inventions and new technologies held in Sebastopol in September united more than 340 participants from 27 countries - Azerbaijan, Algeria, Armenia, Belorussia, Greece, Egypt, Israel, India, Indonesia, Iran, Kazakhstan, Canada, Malaysia, Moldova, UAE, Poland, Portugal, Russia, Romania, Serbia, USA, Taiwan, Tunisia, Turkmenistan, Uzbekistan, Ukraine and Croatia. Since 2005, the Salon has been an expert site promoting production and services of elaborators and manufacturers in the national and world market. The Salon featured elaborations contest, innovations and new technologies fair. Presentations of the participants and ?I International contest of youth innovations and elaborations "New time". The slogan of the project- "Sustainable development during the time of changes".


Zakharov I.I.,East Ukrainian National University | Zakharov I.I.,Technological Institute
Journal of Structural Chemistry | Year: 2014

The adiabatic bound state of an excess electron is calculated for a water cluster (H2O)8 - in the gas phase using the DFT-B3LYP method with the extended 6-311++G(3df,3pd) basis set. For the liquid phase the calculation is performed in the polarizable continuum model (PCM) with regard to the solvent effect (water, ε = 78.38) in the supermolecule-continuum approximation. The value calculated by DFT-B3LYP for the vertical binding energy (VBE) of an excess electron in the anionic cluster (VBE(H2O)8 - = 0.59 eV) agrees well with the experimental value of 0.44 eV obtained from photoelectron spectra in the gas phase. The VBE value of the excess electron calculated by PCM-B3LYP for the (H2O)8 - cluster in the liquid phase (VBE = 1.70 eV) corresponds well to the absorption band maximum λmax = 715 nm (VBE = 1.73 eV) in the optical spectrum of the hydrated electron ehydr -. Estimating the adiabatic binding energy (ABE) ehydr - in the (H2O)8 - cluster (ABE = 1.63 eV), we obtain good agreement with the experimental free energy of electron hydration ΔG298 0 (ehydr -) = 1.61 eV. The local model (H2O)8 2- of the hydrated dielectron is considered in the supermolecule-continuum approximation. It is shown that the hydrated electron and dielectron have the same characteristic local structure: -O-H{↑}H-O- and -O-H{↑↓}H-O- respectively. © 2014 by Pleiades Publishing, Ltd.


Corey S.J.,Northwestern University | Kimmel M.,Rice University | Leonard J.N.,Technological Institute
Advances in Experimental Medicine and Biology | Year: 2014

Hematologists have traditionally studied blood and its components by simplifying it into its components and functions. A variety of new techniques have generated large and complex datasets. Coupled to an appreciation of blood as a dynamic system, a new approach in systems hematology is needed. Systems hematology embraces the multi-scale complexity with a combination of mathematical, engineering, and computational tools for constructing and validating models of biological phenomena. The validity of mathematical modeling in hematopoiesis was established early by the pioneeringwork ofTill and McCulloch. This volume seeks to introduce to the various scientists and physicians to the multi-faceted field of hematology by highlighting recent works in systems biology. Deterministic, stochastic, statistical, and network-based models have been used to better understand a range of topics in hematopoiesis, including blood cell production, the periodicity of cyclical neutropenia, stem cell production in response to cytokine administration, and the emergence of drug resistance. Future advances require technological improvements in computing power, imaging, and proteomics as well as greater collaboration between experimentalists and modelers. Altogether, systems hematology will improve our understanding of normal and abnormal hematopoiesis, better define stem cells and their daughter cells, and potentially lead to more effective therapies. © Springer Science+Business Media NewYork 2014.


Thibault N.,University Pierre and Marie Curie | Husson D.,Copenhagen University | Husson D.,Technological Institute
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2016

New paleoecological data are presented for late Maastrichtian calcareous nannofossil assemblages of the Indian Ocean and the Boreal epicontinental Chalk Sea. These data are compiled with recent results in the tropical Atlantic, Pacific, and Tethys oceans in order to characterize environmental changes by the end of the Cretaceous era. The paleobiogeographic distribution of the warm-water species Micula murus is updated and indicates the existence of major sea-surface currents in the late Maastrichtian Atlantic Ocean similar to the present day. The end-Maastrichtian greenhouse warming is characterized at tropical and subtropical latitudes by an increase in abundance of M. murus and the temporary disappearance of the high-fertility marker Biscutum constans. In the Boreal realm, the greenhouse episode is marked by a contemporaneous acme of Watznaueria barnesiae coincident with very rare occurrences of M. murus and other tropical nannofossil species which have never been reported before at boreal latitudes. A review of cyclostratigraphic and calcareous nannofossil data in the Atlantic, Pacific, Indian, and Tethys oceans points to the following evolution of sea-surface paleotemperatures for the last ca. 350-380 kyr of the Cretaceous: the end-Maastrichtian greenhouse warming lasted on average a little more than 200 kyr and was followed by a ca. 100-120 kyr cooling. In the Tethys, a 30-40 kyr additional pulse of warming is highlighted immediately below the Cretaceous-Paleogene boundary. These findings indicate an important instability of the climate system at the end of the Maastrichtian, most likely caused by Deccan volcanism. The calcareous nannofossil species richness dropped during the end-Maastrichtian greenhouse warming, which may indicate environmental stress and/or ocean acidification. However, nannoplankton diversity returned rapidly to higher values after this climatic episode and remained high up to the Cretaceous-Paleogene boundary. No significant extinction is recorded in this biotic group prior to the boundary clay. © 2015 Elsevier B.V.


Popov A.V.,Georgia Institute of Technology | Popov A.V.,Technological Institute | Viehman D.C.,Georgia Institute of Technology | Hernandez R.,Georgia Institute of Technology
Journal of Chemical Physics | Year: 2011

The temperature-ramped irreversible Langevin equation [A. V. Popov and R. Hernandez, J. Chem. Phys. 134, 244506 (2007)] has been seen to describe the nonequilibrium atomic oscillations of a nanorod dragged across a surface. The nanorod and surface consist of hydroxylated α-Al2O3 layers as was studied earlier by Hase and co-workers [J. Chem. Phys. 122, 094713 (2005)]. The present approach corresponds to the reduced Frenkel-Kontorova- Tomlinson model in which only one element of the vibrational chain representing a surface layer is considered explicitly. The key new concept centers on a separation of the environment into two effective reduced-dimensional baths: an equilibrium bath arising from the thermostated vibrations of the crystal lattice and a nonequilibrium bath arising from driven oscillations at the contact between the nanorod and the surface. The temperature of the latter is defined by the mean energy of a representative atomic oscillator for a given layer. The temporal temperature fluctuations and the dependence of the static part of the temperature on the sliding velocity are close to those found in the MD simulations of Hase and co-workers. © 2011 American Institute of Physics.


Husson D.,Technological Institute | Husson D.,CNRS Institute of Earth Sciences | Thibault N.,Copenhagen University | Galbrun B.,CNRS Institute of Earth Sciences | And 4 more authors.
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2014

Cyclostratigraphic analysis of the Maastrichtian limestone-marl alternations of Bidart (SW France) allows the hypothesis of orbital control on lithological cycles to be evaluated. Magnetic susceptibility (MS), oxygen and carbon isotope measurements, sampled at a high resolution, are analyzed using various cyclostratigraphic tools. A statistically significant orbital signal is detected, with a remarkable record of the precession corresponding to the limestone-marl couplets. This well expressed orbital forcing allows the building of a relative cyclostratigraphic time scale for the MS and δ13C records based on the 100kyr eccentricity cycle. The total duration of the section is estimated at 1.44±0.22Myr. Correlation based on calcareous nannofossil biostratigraphy and comparison of the scaled Bidart δ13C record to the astronomically calibrated δ13C signal of ODP Hole 762C shows that the studied section extends from -71.5 to -70Ma, covering the upper part of Chron C32n.1n and 2/3 of Chron C31r. Oxygen isotope data suggest a 2°C cooling of sea-surface temperatures during the studied interval. When placed on the long-term δ18O trend of the Bidart section, this interval is here recognized as the onset of the early Maastrichtian cooling event. With its excellent record of the precessional forcing, the Bidart section, along with other sections of the Basque Country, is a useful tool for the refinement of the Maastrichtian timescale. © 2013 Elsevier B.V.


PubMed | Technological Institute
Type: Journal Article | Journal: Hellenic journal of cardiology : HJC = Hellenike kardiologike epitheorese | Year: 2015

Heart failure (HF) is a chronic disease associated with significant prevalence, mortality, and health care expenditure. The aim of the present study was to explore the factors associated with anxiety and depression experienced by patients hospitalized with HF.We evaluated 190 hospitalized HF patients in four public hospitals. The data were collected using a specific questionnaire, which, apart from demographic and clinical variables, included the Hospital Anxiety and Depression Scale (HADS).In the total sample, 24.7% and 32.6% of patients were found to have moderate or high levels of anxiety, respectively. Simple multinomial logistic regression showed that no characteristic was significantly associated with anxiety. It also appeared that 17.4% of patients had minor and 24.2% major depression. Among the factors examined, longer disease duration was associated with a higher probability of being depressed (p=0.041). Moreover, single/divorced and widowed patients were more likely to have major depression compared to married patients (35.6% vs. 19.2%, p=0.046). Simple multinomial logistic regression revealed that married patients were 59% less likely to have major depression compared to their unmarried counterparts (OR: 0.41). Moreover, patients with short (<1 year) and moderate (2-5 years) disease duration were 69% (OR: 0.31) and 61% (OR: 0.39) less likely to have major depression compared to those with a long disease duration. Multiple multinomial logistic regression showed that only the disease duration remained statistically significantly associated with depression after controlling for the rest of factors found to be significant at a univariate level.Nurses and physicians must take measures for the identification, assessment and management of anxiety and depression in this clinical population.

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