bluuebunny/crossref_metadata_2025_split huggingface dataset:
Concepts for computer center power management
Authors: DiRienzo A. , Medeiros John A. , Whitlock M. , Wages E. , Highfield J. 
Published: December 2009

AbstractElectrical power usage contributes significantly to the operational costs of large computer systems. At the Hypersonic Missile Technology Research and Operations Center (HMT‐ROC) our system usage patterns provide a significant opportunity to reduce operating costs since there are a small number of dedicated users. The relatively predictable nature of our usage patterns allows for the scheduling of computational resource availability. We take advantage of this predictability to shut down systems during periods of low usage to reduce power consumption. With interconnected computer cluster systems, reducing the number of online nodes is more than a simple matter of throwing the power switch on a portion of the cluster. The paper discusses these issues and an approach for power reduction strategies for a computational system with a heterogeneous system mix that includes a large (1560‐node) Apple Xserve PowerPC supercluster. In practice, the average load on computer systems may be much less than the peak load although the infrastructure supporting the operation of large computer systems in a computer or data center must still be designed with the peak loads in mind. Given that a significant portion of the time, systems loads can be less than full peak, an opportunity exists for cost savings if idle systems can be dynamically throttled back, slept, or shut off entirely. The paper describes two separate strategies that meet the requirements for both power conservation and system availability at HMT‐ROC. The first approach, for legacy systems, is not much more than a brute force approach to power management which we call Time‐Driven System Management (TDSM). The second approach, which we call Dynamic‐Loading System Management (DLSM), is applicable to more current systems with ‘Wake‐on‐LAN’ capability and takes a more granular approach to the management of system resources. The paper details the rule sets that we have developed and implemented in the two approaches to system power management and discusses some results with these approaches. Copyright © 2009 John Wiley & Sons, Ltd.
A Molecular Magnet Confined in the Nanocage of a Globular Protein
Authors: Mitra Rajib K. , Verma Pramod K. , Wulferding Dirk , Menzel Dirk , Mitra Tamoghna , Todea Ana M. , Lemmens Peter , Müller Achim , Pal Samir K. 
Published: December 2009

AbstractThe effect of confinement and energy transfer on the dynamics of a molecular magnet, known as a model system to study quantum coherence, is investigated. For this purpose the well‐known polyoxovanadate [V15As6O42(H2O)]6− (V15) is incorporated into a protein (human serum albumin, HSA) cavity. Due to a huge overlap of the optical absorption spectrum of V15 with the emission spectrum of a fluorescence center of HSA (containing a single tryptophan residue), energy transfer is induced and probed by steady‐state and time‐resolved fluorescence. The geometrical coordination and the distance of the confined V15 to the tryptophan moiety of HSA are investigated at various temperatures. This effect is used as a local probe for the thermal denaturation of the protein at elevated temperatures.
Near‐stoichiometric LiNbO3:ZrO2 single crystal growth by micro pulling down method
Authors: Shur J. W. , Lee H. J. , Yoon D. H. 
Published: December 2009

AbstractCrack‐free, rod‐shaped single crystals of undoped and 0.5, 0.7 and 1.0 mol% ZrO2‐doped LiNbO3 with a near‐stoichiometric composition were grown by the micro‐pulling down (μ‐PD) method. The structural properties of the grown crystals were examined by powder X‐ray diffraction (XRD). Electron probe micro analysis (EPMA) of the near‐stoichiometric LiNbO3 single crystals revealed the homogeneous incorporation of Zr ions. The change in the refractive index and IR transmission spectra of the grown crystals were examined as a function of the Zr concentration. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Phenotypes of stem cells from diverse origin
Authors: Tárnok Attila , Ulrich Henning , Bocsi Jozsef 
Published: December 2009

AbstractStem cells have turned into promising tools for studying the mechanisms of development, regeneration, and for cell therapy of various disorders. Stem cells are found in the embryo and in most adult tissues participating in endogenous tissue regeneration. They are capable of autorenovation, often maintain their multipotency of differentiation into various tissues of their germ line and are, therefore, ideal candidates for cellular therapy taken that they can be unequivocally identified and isolated. In this review, we report stem cell marker expression used for identification of various stem cell lineages, including very small embryonic stem cells, neural, hematopoietic, mesenchymal, epithelial and limbal epithelial stem cells, endothelial progenitor cells, supra‐adventitial adipose stromal cells, adipose pericytes, and cancer stem cells. These cells usually cannot be distinguished by a single stem cell marker, because their expression partially overlaps between lineages. Recent advances in flow cytometry allowing the simultaneous detection of various markers have facilitated stem cell identification for clinical diagnosis and research. So far experimental evidence suggests the existence of cells with different properties, i.e., the capability to different in various cell types. Several studies indicate that expression of classical markers for stem cell classification, such as CD34, CD45, and CD133, may differ between the virtually same stem and progenitor cells, i.e., endothelial progenitor or mesenchymal stem cells, when they were obtained from different tissues. This finding raises questions whether phenotypic differences are due to the source or if it is only caused by different isolation and experimental conditions. © 2009 International Society for Advancement of Cytometry
Outer‐Sphere Redox Reactions Leading to the Formation of Discrete CoIII/FeII Pyrazine‐Bridged Mixed‐Valence Compounds
Authors: Bernhardt Paul V. , Martínez Manuel , Rodríguez Carlos 
Published: December 2009

AbstractThe kinetic and mechanistic study of the reaction of complexes [CoIIIXL]n+ [X = Cl, OH, H2O; L = (NH3)5, transL14, transL14S, in which L14 and L14S are pentadentate macrocyclic ligands] with [FeII(CN)5(pz)]3– (pz = 1,4‐pyrazine) has been carried out as a function of the ligands, temperature and pressure. The results indicate that the previously established redox‐triggered formal substitution process (i.e., [CoIIIXL]n+ + [FeII(CN)5(pz)]3– → {CoIIL} + [FeIII(CN)5(pz)]2– → [LCoII(pz)FeIII(CN)5] → [LCoIII(pz)FeII(CN)5]), which was found to be actuating for the reaction with [FeII(CN)6]4–, also applies. The final mixed‐valence Class II complexes [LCoIII(pz)FeII(CN)5] are formed whenever the {CoIIL} moieties occurring after the initial outer‐sphere reduction are stable enough (L being macrocyclic encapsulating ligands), whereas decomposition from the {CoIIL} + [FeIII(CN)5(pz)]2– solution occurs for the pentaamino systems. The stability of the encounter complexes involved in the initial outer‐sphere redox process seems to play a crucial role in these processes. Fuoss ion pairing does not seem to apply and no correlation between the kinetic parameters and the redox potential for the reaction was found. The final stable mixed‐valence Class II compounds have been fully characterized in solution and their electrochemistry and UV/Vis characteristics agree with the expected trends. Nevertheless, both photochemistry and FeII–N(pz) bond lability prevents their isolation as solids from the solutions purified by chromatography.
A Selective Chromogenic and Fluorescent Molecular Probe for YbIIIBased on a Bichromophoric Azadiene
Authors: Zapata Fabiola , Caballero Antonio , Espinosa Arturo , Tárraga Alberto , Molina Pedro 
Published: December 2009

AbstractA new structurally simple motif, where two anthracene moieties are linked by a 2‐aza‐1,3‐butadiene bridge has been synthesized and characterized. This new molecular probe senses Yb3+metal cations through two different channels: a colour change from yellowish to orange, which can be used for its “naked‐eye” detection, and a remarkable enhancement in the fluorescence, even in the presence of other trivalent lanthanide metal cations.
Tetra[6,7]quinoxalinoporphyrazines: The Effect of an Additional Benzene Ring on Photophysical and Photochemical Properties
Authors: Novakova Veronika , Zimcik Petr , Miletin Miroslav , Kopecky Kamil , Musil Zbynek 
Published: December 2009

AbstractSynthetic methods for a series of zinc tetra[6,7]quinoxalinoporphyrazines (6,7‐TQP) with peripheral chains connected through the S, O and N heteroatoms as well as through the C–C bond were developed. Photophysical and photochemical properties of 6,7‐TQP were compared with tetrapyrazinoporphyrazines (TPP) bearing the same peripheral substituents to disclose the effect of insertion of a benzene ring between the pyrazine and porphyrazine moieties. The influence of the peripheral heteroatom in the group of 6,7‐TQP is also discussed. Prepared 6,7‐TQP have their main absorption band (Q‐band) strongly batho‐ and hyperchromically shifted (λmax = 730–770 nm in pyridine, ϵ up to 500000 dm3 mol–1cm–1) in comparison to TPP. They showed high singlet oxygen quantum yields (ΦΔ = 0.50–0.74) and relatively lowfluorescence quantum yields (ΦF < 0.08).
Monodispersed submicron porous silica particles functionalized with CD derivatives for chiral CEC
Authors: Li Lai‐Sheng , Wang Yong , James Young David , Ng Siu‐Choon , Tan Timothy Thatt Yang 
Published: December 2009

AbstractRapid and efficient enantioseparation of halogen aryl alcohols and β‐blockers propranolol and pindolol in packed bed CEC (p‐CEC) using as‐prepared submicron porous silica chiral stationary phases (CSPs) has been achieved. Monodispersed 0.66 and 0.81 μm chiral submicron porous silica spheres were prepared using tetramethoxysilane and hexadecyltrimethylammonium bromide, followed by a hydrothermal treatment method with ammonia–ethanol to expand the pore of silica spheres without changing their spherical morphology. A proper specific surface of ca. 230 m2/g and pore sizes average of 6–8 nm were obtained by this method. The submicron porous silica spheres were modified with mono‐6‐phenylcarbamoylated β‐CD via thiol‐en radical addition. They were packed into 9 cm 50 μm id capillary columns with photopolymerized monolithic frits. These submicron CSPs showed greater column efficiency (about 476  000 plates/m for 4‐iodophenyl‐1‐ethanol) and higher resolution than the corresponding 3 μm CSP.
An electrophoretic method for the detection of chymotrypsin and trypsin activity directly in whole blood
Authors: Lefkowitz Roy B. , Marciniak Jennifer Y. , Hu Che‐Ming , Schmid‐Schönbein Geert W. , Heller Michael J. 
Published: December 2009

AbstractIn biomedical research and clinical diagnostics, it is a major challenge to measure disease‐related degradative enzyme activity directly in whole blood. Present techniques for assaying degradative enzyme activity require sample preparation, which makes the assays time‐consuming and costly. This study now describes a simple and rapid electrophoretic method that allows detection of degradative enzyme activity directly in whole blood using charge‐changing fluorescent peptide substrates. Charge‐changing substrates eliminate the need for sample preparation by producing positively charged cleavage fragments that can be readily separated from the oppositely charged fluorescent substrate and blood components by electrophoresis. Two peptide substrates have been developed for pancreatic α‐chymotrypsin and trypsin. For the first substrate, a detection limit of 3 ng for both α‐chymotrypsin and trypsin was achieved in whole rat blood using a 4% agarose gel. This substrate had minimal cross‐reactivity with the trypsin‐like proteases thrombin, plasmin, and kallikrein. For the second substrate (trypsin‐specific), a detection limit of about 10–20 pg was achieved using thinner higher resolution 20 and 25% polyacrylamide gels. Thus, the new charge changing peptide substrates enable a simple electrophoretic assay format for the measurement of degradative enzyme activity, which is an important step toward the development of novel point‐of‐care diagnostics.
Phylogenetics of Vicia (Fabaceae) based on morphological data
Authors: Leht M. 
Published: December 2009

AbstractThe phylogenetic relationships among 67 Vicia species from Eurasia were studied in relation to Trifolium montanum on the basis of 91 morphological characters. The characters were coded as multistate, 17 were treated as ordered. In subgenus Vicia, V. sepium and V. oroboides form a separate taxon, section Sepium, into which V. grandiflora should be included. Separation of V. lathyroides and V. cuspidata into a distinct section Lathyroides is supported. Placement of V. mollis into section Hypechusa is supported, however, treatment of V. hyrcanica and V. noeana in a separate taxon, series Hyrcanicae, is not supported and needs further study. Joining of V. faba to the Narbonensis group is well supported. In subgenus Cracca, sections Vicilla and Cassubicae appear monophyletic when V. amoena is moved from section Vicilla to section Cassubicae. Section Variegatae does not appear monophyletic, as V. argentea and V. canescens, although closely connected, belong to section Cracca.The present analysis supports separation of the Ervoid group (V. tetrasperma, V. tenuissima, V. pubescens, and V. caesarea) into an independent subgenus, subgenus Ervum; the position of V. hirsuta remains disputable. Therefore, division of Vicia into three subgenera is supported. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Pollen types of the Egyptian species of the genus Salvia (Lamiaceae)
Authors: Hassan N. , Osman A. K. , El Garf I. A. 
Published: December 2009

AbstractPollen morphology of seven species of genus Salvia (Lamiaceae) was investigated using light and scanning electron microscopy. Pollen was studied to show all possible characteristic features like shape, size, apertures, wall stratification, etc., with special reference to the specific characters of each pollen type. Four pollen types were recognized viz. Salvia aegyptiaca pollen type, Salvia deserti pollen type, Salvia palaestina pollen type and Salvia spinosa pollen type. Description of each type, a key to the investigated taxa as well as SEM micrographs of pollen types are provided. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Evaluation of RuxWySez Catalyst as a Cathode Electrode in a Polymer Electrolyte Membrane Fuel Cell
Authors: Suárez‐Alcántara K. , Solorza‐Feria O. 
Published: December 2009

AbstractThe oxygen reduction reaction (ORR) on RuxWySez is of great importance in the development of a novel cathode electrode in a polymer electrolyte membrane fuel cell (PEMFC) technology. The RuxWySez electrocatalyst was synthesised in an organic solvent for 3 h. The powder was characterised by transmission electron microscopy (TEM), and powder X‐ray diffraction (XRD). The electrocatalyst consisted of agglomerates of nanometric size (∼50–150 nm) particles. In the electrochemical studies, rotating disc electrode (RDE) and rotating ring‐disc electrode (RRDE) techniques were used to determine the oxygen reduction kinetics in 0.5 M H2SO4. The kinetic studies include the determination of Tafel slope (112 mV dec–1), exchange current density at 25 °C (1.48 × 10–4 mA cm–2) and the apparent activation energy of the oxygen reaction (52.1 � 0.4 kJ mol–1). Analysis of the data shows a multi‐electron charge transfer process to water formation, with 2% H2O2 production. A single PEMFC with the RuxWySez cathode catalysts generated a power density of 180 mW cm–2. Performance achieved with a loading of 1.4 mg cm–2 of a 40 wt% RuxWySez and 60 wt% carbon Vulcan (i.e. 0.56 mg cm–2 of pure RuxWySez). Single PEMFC working was obtained with hydrogen and oxygen at 80 °C with 30 psi.
The Development and Application of a Novel Optimisation Strategy for Solid Oxide Fuel Cell‐Gas Turbine Hybrid Cycles
Authors: Zhao Y. , Shah N. , Brandon N. 
Published: December 2009

AbstractA combined power system with solid oxide fuel cell (SOFC) and gas turbine (GT) is modelled and analysed thermodynamically in this paper. A novel optimisation strategy including the design of optimal parameters is proposed and applied to the hybrid system. Different sources of irreversible losses are specified, and entropy analyses are used to indicate the multi‐irreversibilities existing, and to assess the work potentials of the system. Expressions of the power output and efficiency for both the subsystems and the SOFC‐GT hybrid system are derived. The optimal performance characteristics are presented and discussed in detail through a parametric analysis. The developed model is expected to provide not only a convenient tool to determine the optimal system performance and component irreversibility, but also an appropriate basis to design similar complex hybrid power plants. This new approach can be further extended to other energy conversion settings and electrochemical systems. Decision makers should therefore find the methodology contained in this paper useful in the comparison and selection of advanced heat recovery systems.
Structural neuroplasticity in the sensorimotor network of professional female ballet dancers
Authors: Hänggi Jürgen , Koeneke Susan , Bezzola Ladina , Jäncke Lutz 
Published: December 2009

AbstractEvidence suggests that motor, sensory, and cognitive training modulates brain structures involved in a specific practice. Functional neuroimaging revealed key brain structures involved in dancing such as the putamen and the premotor cortex. Intensive ballet dance training was expected to modulate the structures of the sensorimotor network, for example, the putamen, premotor cortex, supplementary motor area (SMA), and the corticospinal tracts. We investigated gray (GM) and white matter (WM) volumes, fractional anisotropy (FA), and mean diffusivity (MD) using magnetic resonance‐based morphometry and diffusion tensor imaging in 10 professional female ballet dancers compared with 10 nondancers. In dancers compared with nondancers, decreased GM volumes were observed in the left premotor cortex, SMA, putamen, and superior frontal gyrus, and decreased WM volumes in both corticospinal tracts, both internal capsules, corpus callosum, and left anterior cingulum. FA was lower in the WM underlying the dancers' left and right premotor cortex. There were no significant differences in MD between the groups. Age of dance commencement was negatively correlated with GM and WM volume in the right premotor cortex and internal capsule, respectively, and positively correlated with WM volume in the left precentral gyrus and corpus callosum. Results were not influenced by the significantly lower body mass index of the dancers. The present findings complement the results of functional imaging studies in experts that revealed reduced neural activity in skilled compared with nonskilled subjects. Reductions in brain activity are accompanied by local decreases in GM and WM volumes and decreased FA. Hum Brain Mapp, 2010. © 2009 Wiley‐Liss, Inc.
In vitro studies on the influence of surface modification of Ni–Ti alloy on human bone cells
Authors: Chrzanowski Wojciech , Neel Ensanya A. Abou , Armitage David A. , Zhao Xin , Knowles Jonathan C. , Salih Vehid 
Published: December 2009

AbstractThe in vitro cell behavior on Nitinol™ after different surface treatments was investigated. As references samples, commercially pure titanium (cpTi) and bioactive titanium were used. The surface treatments influenced the topography, surface energy, crystallographic structure, ion release, chemistry, and ability to form apatite layer from simulated body fluids. Regardless of the surface treatment, the bioactivity study showed that the kinetics of apatite film formation was similar for all tested samples. No clear indication of the surface characteristics influence on the ability for calcium‐phosphate precipitation was evident. Cell activity studies showed that ground nickel titanium, spark oxidized and thermally oxidized (at 400°C and below) had higher cellular activity and caused increased alkaline phosphatase (ALP) and osteocalcin (OC) expression which was comparable to control tissue culture plastic and titanium reference samples. Regardless of surface modifications, preimmersion of the samples in media for 72 h resulted in cell proliferation at the same level for all samples. Therefore, it can be concluded that preconditioning of samples alters surface properties and modulates the cell response regardless of the initial surface treatment and its properties. Moreover, a detrimental effect on cell response was observed after 7 and 14 days in culture for alkali treated samples. This was attributed to a high surface nickel concentration and a high nickel ion release rate from these surfaces. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Intravaginal and in vitro temperature changes with tampons of differing composition and absorbency
Authors: Hill Donna R. , Davis Catherine C. , Osborn Thomas W. 
Published: December 2009

AbstractVaginal tampons are Class II medical devices used by women to manage menstruation. The purpose of this study was to investigate intravaginal temperature changes with simulated and actual menstrual tampon use. Tampons (with varying absorbent compositions) embedded with a thermocouple sensor were used to study temperature effects in vitro in a model of the vagina (condom placed in a hollow glass tube, jacketed in a 37°C water bath, and dosed with human menses to fluid saturation) and clinically during menstrual tampon wear under controlled conditions (up to 8 h in a stationary, supine position). Elevations in the temperature of the tampon core occurred upon menses fluid acquisition both in vitro and clinically. Temperature profile characteristics varied from a transient spike with commercial cotton‐rayon blend tampons of two different absorbencies to a small but sustained rise (≥6 h) with a carboxymethyl cellulose (CMC)‐containing prototype. On the basis of the results from this study, fluid absorption by tampons generates an exothermic event whose characteristics vary with tampon design and composition. We speculate the small, sustained increased in tampon temperature noted during this study may enhance the production of a bacterial exotoxin associated with tampons composed of CMC. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010