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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. Source

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. Source

Husson D.,Technological Institute | Husson D.,CNRS Paris Institute of Earth Sciences | Galbrun B.,CNRS Paris Institute of Earth Sciences | Gardin S.,CNRS Center for Research on Palaeobiodiversity and Palaeoenvironments | Thibault N.,Copenhagen University
Stratigraphy | Year: 2014

The complex interplay between extraterrestrial events and earth-bound processes that triggered one of the greatest biological crises of the Phanerozoic requires a high resolution timescale. Detailed magnetic susceptibility measurements at the Contessa Highway and Bottaccione sections (Italy) span the Cretaceous-Paleogene boundary and reveal clear orbital signatures in the sedimentary record. Identification of precession and 405 kyr eccentricity cycles allows an estimate of 324+/-40 kyr for the duration of the Maastrichtian part of Chron C29r. We present in the same high resolution time frame sites in Spain and the North and South Atlantic and bio-horizons, biotic changes, stable isotopic excursions and the decrease in Osmium isotopes recorded in these sections. The onset of 187Os/188Os decrease coincides with the δ13C negative excursion K-PgE1, thus suggesting a first pulse in Deccan volcanism at 66.64 Ma. The K-PgE3 δ13C negative excursion is possibly the expression of a second pulse at 66.26 Ma. Late Maastrichtian δ13C negative excursions are of low intensity and span durations of one to two eccentricity cycles, whereas early Danian excursions are brief (about 30 kyr) and acute. Biotic response to late Maastrichtian perturbations occurred with a delay of ca. 200 kyr after the beginning of K-PgE1 shortly before K-PgE3. The biotic perturbation could be thus either a delayed response to K-PgE1, or a direct response to K-PgE3, and possibly, a threshold response to the stepwise buildup of CO2 atmospheric injections. No delay is evident in response to early Danian hyperthermal events. These differences suggest that short-lived, volcanically-derived environmental perturbations were buffered within the stable late Maastrichtian oceanic realm whereas they were amplified by the more sensitive and highly disturbed early Danian oceanic ecosystem. Source

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. Source

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. Source

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