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Sample records for cde phase activity

  1. Results from the CDE phase activity on neutron dosimetry for the international fusion materials irradiation facility test cell

    CERN Document Server

    Esposito, B; Maruccia, G; Petrizzi, L; Bignon, G; Blandin, C; Chauffriat, S; Lebrun, A; Recroix, H; Trapp, J P; Kaschuck, Y

    2000-01-01

    The international fusion materials irradiation facility (IFMIF) project deals with the study of an accelerator-based, deuterium-lithium source, producing high energy neutrons at sufficient intensity and irradiation volume to test samples of candidate materials for fusion energy reactors. IFMIF would also provide calibration and validation of data from fission reactor and other accelerator based irradiation tests. This paper describes the activity on neutron/gamma dosimetry (necessary for the characterization of the specimens' irradiation) performed in the frame of the IFMIF conceptual design evaluation (CDE) neutronics tasks. During the previous phase (conceptual design activity (CDA)) the multifoil activation method was proposed for the measurement of the neutron fluence and spectrum and a set of suitable foils was defined. The cross section variances and covariances of this set of foils have now been used for tests on the sensitivity of the IFMIF neutron spectrum determination to cross section uncertainties...

  2. Identification and functional analysis of a CDE/CHR element in the POLD1 promoter

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    DNA polymerase delta is encoded by the POLD1 gene,the transcription of which is strictly cell cycle-dependent.However,the means by which POLD1 transcription is regulated by the cell cycle mechanism is currently unknown.We discovered a novel element in the POLD1 promoter known as a CDE(cell cycle-dependent element)/CHR(cell cycle gene homology region) element.A series of luciferase reporter constructs containing various POLD1 promoter mutations were used to investigate the role of the CDE/CHR element in POLD1 transcription.When the CDE/CHR element was mutated,the promoter activity was up-regulated,and the cell-cycle related factors E2F1 and p21 stopped regulating the promoter.Furthermore,cell cycle-dependent changes in the promoter activity required the integrative CDE/CHR element.Electrophoretic mobility shift assay(EMSA) revealed the presence of at least three types of DNA/protein complexes binding to the CDE/CHR element.Our findings provide strong evidence that the CDE/CHR-like sequence is an active functional element in the POLD1 promoter,which is important for the cell cycle regulation of the POLD1 gene.

  3. The p53-p21-DREAM-CDE/CHR pathway regulates G2/M cell cycle genes.

    Science.gov (United States)

    Fischer, Martin; Quaas, Marianne; Steiner, Lydia; Engeland, Kurt

    2016-01-01

    The tumor suppressor p53 functions predominantly as a transcription factor by activating and downregulating gene expression, leading to cell cycle arrest or apoptosis. p53 was shown to indirectly repress transcription of the CCNB2, KIF23 and PLK4 cell cycle genes through the recently discovered p53-p21-DREAM-CDE/CHR pathway. However, it remained unclear whether this pathway is commonly used. Here, we identify genes regulated by p53 through this pathway in a genome-wide computational approach. The bioinformatic analysis is based on genome-wide DREAM complex binding data, p53-depedent mRNA expression data and a genome-wide definition of phylogenetically conserved CHR promoter elements. We find 210 target genes that are expected to be regulated by the p53-p21-DREAM-CDE/CHR pathway. The target gene list was verified by detailed analysis of p53-dependent repression of the cell cycle genes B-MYB (MYBL2), BUB1, CCNA2, CCNB1, CHEK2, MELK, POLD1, RAD18 and RAD54L. Most of the 210 target genes are essential regulators of G2 phase and mitosis. Thus, downregulation of these genes through the p53-p21-DREAM-CDE/CHR pathway appears to be a principal mechanism for G2/M cell cycle arrest by p53.

  4. The Transcriptional Repressor, MtrR, of the mtrCDE Efflux Pump Operon of Neisseria gonorrhoeae Can Also Serve as an Activator of “off Target” Gene (glnE Expression

    Directory of Open Access Journals (Sweden)

    Paul J. T. Johnson

    2015-06-01

    Full Text Available MtrR is a well-characterized repressor of the Neisseria gonorrhoeae mtrCDE efflux pump operon. However, results from a previous transcriptional profiling study suggested that MtrR also represses or activates expression of at least sixty genes outside of the mtr locus. Evidence that MtrR can directly repress so-called “off target” genes has previously been reported; in particular, MtrR was shown to directly repress glnA, which encodes glutamine synthetase. In contrast, evidence for the ability of MtrR to directly activate expression of gonococcal genes has been lacking; herein, we provide such evidence. We now report that MtrR has the ability to directly activate expression of glnE, which encodes the dual functional adenyltransferase/deadenylase enzyme GlnE that modifies GlnA resulting in regulation of its role in glutamine biosynthesis. With its capacity to repress expression of glnA, the results presented herein emphasize the diverse and often opposing regulatory properties of MtrR that likely contributes to the overall physiology and metabolism of N. gonorrhoeae.

  5. The Transcriptional Repressor, MtrR, of the mtrCDE Efflux Pump Operon of Neisseria gonorrhoeae Can Also Serve as an Activator of "off Target" Gene (glnE) Expression.

    Science.gov (United States)

    Johnson, Paul J T; Shafer, William M

    2015-06-01

    MtrR is a well-characterized repressor of the Neisseria gonorrhoeae mtrCDE efflux pump operon. However, results from a previous transcriptional profiling study suggested that MtrR also represses or activates expression of at least sixty genes outside of the mtr locus. Evidence that MtrR can directly repress so-called "off target" genes has previously been reported; in particular, MtrR was shown to directly repress glnA, which encodes glutamine synthetase. In contrast, evidence for the ability of MtrR to directly activate expression of gonococcal genes has been lacking; herein, we provide such evidence. We now report that MtrR has the ability to directly activate expression of glnE, which encodes the dual functional adenyltransferase/deadenylase enzyme GlnE that modifies GlnA resulting in regulation of its role in glutamine biosynthesis. With its capacity to repress expression of glnA, the results presented herein emphasize the diverse and often opposing regulatory properties of MtrR that likely contributes to the overall physiology and metabolism of N. gonorrhoeae. PMID:26078871

  6. Athena: Assessment Phase Activities

    Science.gov (United States)

    Lumb, David; Ayre, Mark

    2015-09-01

    The Athena mission concept has been proposed by the community in response to science themes of the Hot and Energetic Universe. Unlike other, competitive, mission selection exercises this "Large" class observatory mission has essentially been pre-selected. Nevertheless it has to be demonstrated that Athena meets the programmatic constraints of 1Bn euro cost cap, and a readiness level appropriate for formal mission adoption by the end 2019. This should be confirmed through a Phase A study conducted with two parallel industry activities. We describe the technical and programmatic content of these and latest progress in space and ground segment definition.

  7. Membrane topology and functional importance of the periplasmic region of ABC transporter LolCDE.

    Science.gov (United States)

    Yasuda, Masaki; Iguchi-Yokoyama, Asako; Matsuyama, Shin-ichi; Tokuda, Hajime; Narita, Shin-ichiro

    2009-10-01

    The LolCDE complex is an ATP-binding cassette transporter that mediates the release of newly synthesized lipoproteins from the cytoplasmic membrane of gram-negative bacteria, which results in the initiation of outer-membrane sorting of lipoproteins through the Lol pathway. LolCDE is composed of one copy each of membrane subunits LolC and LolE, and two copies of nucleotide-binding subunit LolD. In this study, we examined the membrane topology of LolC and LolE by PhoA fusion analysis. Both LolC and LolE were found to have four transmembrane segments with a large periplasmic loop exposed to the periplasm. Despite similarities in sequence and topology, the accessibility of a sulfhydryl reagent to Cys introduced into the periplasmic loop suggested that the structure of the periplasmic region differs between LolC and LolE. Inhibition of the release of lipoproteins by the sulfhydryl reagent supported a previous proposal that LolC and LolE have distinct functions. PMID:19809197

  8. Optimal operation for 3 control parameters of Texaco coal-water slurry gasifier with MO-3LM-CDE algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Cuiwen; Zhang, Yakun; Gu, Xingsheng [Ministry of Education, East China Univ. of Science and Technology, Shanghai (China). Key Lab. of Advanced Control and Optimization for Chemical Processes

    2013-07-01

    Optimizing operation parameters for Texaco coal-water slurry gasifier with the consideration of multiple objectives is a complicated nonlinear constrained problem concerning 3 BP neural networks. In this paper, multi-objective 3-layer mixed cultural differential evolution (MO-3LM-CDE) algorithms which comprise of 4 multi-objective strategies and a 3LM-CDE algorithm are firstly presented. Then they are tested in 6 benchmark functions. Finally, the MO-3LM-CDE algorithms are applied to optimize 3 control parameters of the Texaco coal-water slurry gasifier in methanol production of a real-world chemical plant. The simulation results show that multi-objective optimal results are better than the respective single-objective optimal operations.

  9. Comparison of CDE data in phacoemulsification between an open hospital-based ambulatory surgical center and a free-standing ambulatory surgical center

    Directory of Open Access Journals (Sweden)

    Ming Chen

    2010-11-01

    Full Text Available Ming Chen1, Mindy Chen21University of Hawaii, Honolulu, HI, USA; 2University of California, Irvine, CA, USAAbstract: Mean CDE (cumulative dissipated energy values were compared for an open hospital-based surgical center and a free-standing surgical center. The same model of phacoemulsifier (Alcon Infiniti Ozil was used. Mean CDE values showed that surgeons (individual private practice at the free-standing surgical center were more efficient than surgeons (individual private practice at the open hospital-based surgical center (mean CDE at the hospital-based surgical center 18.96 seconds [SD = 12.51]; mean CDE at the free-standing surgical center 13.2 seconds [SD = 9.5]. CDE can be used to monitor the efficiency of a cataract surgeon and surgical center in phacoemulsification. The CDE value may be used by institutions as one of the indicators for quality control and audit in phacoemulsification.Keywords: CDE (cumulative dissipated energy, open hospital-based ambulatory surgical center, free-standing surgical center, phacoemulsification 

  10. DNA deformability changes of single base pair mutants within CDE binding sites in S. Cerevisiae centromere DNA correlate with measured chromosomal loss rates and CDE binding site symmetries

    Directory of Open Access Journals (Sweden)

    Marx Kenneth A

    2006-03-01

    Full Text Available Abstract Background The centromeres in yeast (S. cerevisiae are organized by short DNA sequences (125 bp on each chromosome consisting of 2 conserved elements: CDEI and CDEIII spaced by a CDEII region. CDEI and CDEIII are critical sequence specific protein binding sites necessary for correct centromere formation and following assembly with proteins, are positioned near each other on a specialized nucleosome. Hegemann et al. BioEssays 1993, 15: 451–460 reported single base DNA mutants within the critical CDEI and CDEIII binding sites on the centromere of chromosome 6 and quantitated centromere loss of function, which they measured as loss rates for the different chromosome 6 mutants during cell division. Olson et al. Proc Natl Acad Sci USA 1998, 95: 11163–11168 reported the use of protein-DNA crystallography data to produce a DNA dinucleotide protein deformability energetic scale (PD-scale that describes local DNA deformability by sequence specific binding proteins. We have used the PD-scale to investigate the DNA sequence dependence of the yeast chromosome 6 mutants' loss rate data. Each single base mutant changes 2 PD-scale values at that changed base position relative to the wild type. In this study, we have utilized these mutants to demonstrate a correlation between the change in DNA deformability of the CDEI and CDEIII core sites and the overall experimentally measured chromosome loss rates of the chromosome 6 mutants. Results In the CDE I and CDEIII core binding regions an increase in the magnitude of change in deformability of chromosome 6 single base mutants with respect to the wild type correlates to an increase in the measured chromosome loss rate. These correlations were found to be significant relative to 105 Monte Carlo randomizations of the dinucleotide PD-scale applied to the same calculation. A net loss of deformability also tends to increase the loss rate. Binding site position specific, 4 data-point correlations were also

  11. Overexpression of LolCDE Allows Deletion of the Escherichia coli Gene Encoding Apolipoprotein N-Acyltransferase ▿

    OpenAIRE

    Narita, Shin-ichiro; Tokuda, Hajime

    2011-01-01

    Bacterial lipoproteins represent a subset of membrane-associated proteins that are covalently modified with lipids at the N-terminal cysteine. The final step of lipoprotein modification, N-acylation of apolipoproteins, is mediated by apolipoprotein N-acyltransferase (Lnt). Examinations with reconstituted proteoliposomes and a conditional mutant previously indicated that N-acylation of lipoproteins is required for their efficient release from the inner membrane catalyzed by LolA and LolCDE, th...

  12. An absorbing phase transition from a structured active particle phase

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, Cristobal [Instituto Mediterraneo de Estudios Avanzados IMEDEA (CSIC-UIB), Campus de la Universidad de las Islas Baleares, E-07122 Palma de Mallorca (Spain); Ramos, Francisco [Departamento de Electromagnetismo y Fisica de la Materia and Instituto de Fisica Teorica y Computacional Carlos I, Facultad de Ciencias, Universidad de Granada, 18071 Granada (Spain); Hernandez-GarcIa, Emilio [Instituto Mediterraneo de Estudios Avanzados IMEDEA (CSIC-UIB), Campus de la Universidad de las Islas Baleares, E-07122 Palma de Mallorca (Spain)

    2007-02-14

    In this work we study the absorbing state phase transition of a recently introduced model for interacting particles with neighbourhood-dependent reproduction rates. The novelty of the transition is that as soon as the active phase is reached by increasing a control parameter a periodically arranged structure of particle clusters appears. A numerical study in one and two dimensions shows that the system falls into the directed percolation universality class.

  13. Phase Transitions in Model Active Systems

    Science.gov (United States)

    Redner, Gabriel S.

    The amazing collective behaviors of active systems such as bird flocks, schools of fish, and colonies of microorganisms have long amazed scientists and laypeople alike. Understanding the physics of such systems is challenging due to their far-from-equilibrium dynamics, as well as the extreme diversity in their ingredients, relevant time- and length-scales, and emergent phenomenology. To make progress, one can categorize active systems by the symmetries of their constituent particles, as well as how activity is expressed. In this work, we examine two categories of active systems, and explore their phase behavior in detail. First, we study systems of self-propelled spherical particles moving in two dimensions. Despite the absence of an aligning interaction, this system displays complex emergent dynamics, including phase separation into a dense active solid and dilute gas. Using simulations and analytic modeling, we quantify the phase diagram and separation kinetics. We show that this nonequilibrium phase transition is analogous to an equilibrium vapor-liquid system, with binodal and spinodal curves and a critical point. We also characterize the dense active solid phase, a unique material which exhibits the structural signatures of a crystalline solid near the crystal-hexatic transition point, as well as anomalous dynamics including superdiffusive motion on intermediate timescales. We also explore the role of interparticle attraction in this system. We demonstrate that attraction drastically changes the phase diagram, which contains two distinct phase-separated regions and is reentrant as a function of propulsion speed. We interpret this complex situation with a simple kinetic model, which builds from the observed microdynamics of individual particles to a full description of the macroscopic phase behavior. We also study active nematics, liquid crystals driven out of equilibrium by energy-dissipating active stresses. The equilibrium nematic state is unstable in these

  14. Active impedance metasurface with full 360° reflection phase tuning

    OpenAIRE

    Zhu, Bo O.; Junming Zhao; Yijun Feng

    2013-01-01

    Impedance metasurface is composed of electrical small scatters in two dimensional plane, of which the surface impedance can be designed to produce desired reflection phase. Tunable reflection phase can be achieved by incorporating active element into the scatters, but the tuning range of the reflection phase is limited. In this paper, an active impedance metasurface with full 360° reflection phase control is presented to remove the phase tuning deficiency in conventional approach. The unit ce...

  15. An Optimal Free Energy Dissipation Strategy of the MinCDE Oscillator in Regulating Symmetric Bacterial Cell Division.

    Directory of Open Access Journals (Sweden)

    Liping Xiong

    2015-08-01

    Full Text Available Sustained molecular oscillations are ubiquitous in biology. The obtained oscillatory patterns provide vital functions as timekeepers, pacemakers and spacemarkers. Models based on control theory have been introduced to explain how specific oscillatory behaviors stem from protein interaction feedbacks, whereas the energy dissipation through the oscillating processes and its role in the regulatory function remain unexplored. Here we developed a general framework to assess an oscillator's regulation performance at different dissipation levels. Using the Escherichia coli MinCDE oscillator as a model system, we showed that a sufficient amount of energy dissipation is needed to switch on the oscillation, which is tightly coupled to the system's regulatory performance. Once the dissipation level is beyond this threshold, unlike stationary regulators' monotonic performance-to-cost relation, excess dissipation at certain steps in the oscillating process damages the oscillator's regulatory performance. We further discovered that the chemical free energy from ATP hydrolysis has to be strategically assigned to the MinE-aided MinD release and the MinD immobilization steps for optimal performance, and a higher energy budget improves the robustness of the oscillator. These results unfold a novel mode by which living systems trade energy for regulatory function.

  16. Disruption of lolCDE, Encoding an ATP-Binding Cassette Transporter, Is Lethal for Escherichia coli and Prevents Release of Lipoproteins from the Inner Membrane

    OpenAIRE

    Narita, Shin-ichiro; Tanaka, Kimie; Matsuyama, Shin-ichi; Tokuda, Hajime

    2002-01-01

    ATP-binding cassette transporter LolCDE was previously identified, by using reconstituted proteoliposomes, as an apparatus catalyzing the release of outer membrane-specific lipoproteins from the inner membrane of Escherichia coli. Mutations resulting in defective LolD were previously shown to be lethal for E. coli. The amino acid sequences of LolC and LolE are similar to each other, but the necessity of both proteins for lipoprotein release has not been proved. Moreover, previous reconstituti...

  17. Molecular Events Involved in a Single Cycle of Ligand Transfer from an ATP Binding Cassette Transporter, LolCDE, to a Molecular Chaperone, LolA*

    OpenAIRE

    Taniguchi, Naohiro; Tokuda, Hajime

    2008-01-01

    An ATP binding cassette transporter LolCDE complex releases lipoproteins from the inner membrane of Escherichia coli in an ATP-dependent manner, leading to the formation of a complex between a lipoprotein and a periplasmic chaperone, LolA. LolA is proposed to undergo a conformational change upon the lipoprotein binding. The lipoprotein is then transferred from the LolA-lipoprotein complex to the outer membrane via LolB. Unlike most ATP binding cassette transporters med...

  18. Active metasurface terahertz deflector with phase discontinuities.

    Science.gov (United States)

    Su, Xiaoqiang; Ouyang, Chunmei; Xu, Ningning; Cao, Wei; Wei, Xin; Song, Guofeng; Gu, Jianqiang; Tian, Zhen; O'Hara, John F; Han, Jiaguang; Zhang, Weili

    2015-10-19

    Metasurfaces provide great flexibility in tailoring light beams and reveal unprecedented prospects on novel functional components. However, techniques to dynamically control and manipulate the properties of metasurfaces are lagging behind. Here, for the first time to our knowledge, we present an active wave deflector made from a metasurface with phase discontinuities. The active metasurface is capable of delivering efficient real-time control and amplitude manipulation of broadband anomalous diffraction in the terahertz regime. The device consists of complementary C-shape split-ring resonator elements fabricated on a doped semiconductor substrate. Due to the Schottky diode effect formed by the hybrid metal-semiconductor, the real-time conductivity of the doped semiconductor substrate is modified by applying an external voltage bias, thereby effectively manipulating the intensity of the anomalous deflected terahertz wave. A modulation depth of up to 46% was achieved, while the characteristics of broadband frequency responses and constant deflected angles were well maintained during the modulation process. The modulation speed of diffraction amplitude reaches several kilohertz, limited by the capacitance and resistance of the depletion region. The scheme proposed here opens up a novel approach to develop tunable metasurfaces. PMID:26480376

  19. Active impedance metasurface with full 360° reflection phase tuning

    Science.gov (United States)

    Zhu, Bo O.; Zhao, Junming; Feng, Yijun

    2013-01-01

    Impedance metasurface is composed of electrical small scatters in two dimensional plane, of which the surface impedance can be designed to produce desired reflection phase. Tunable reflection phase can be achieved by incorporating active element into the scatters, but the tuning range of the reflection phase is limited. In this paper, an active impedance metasurface with full 360° reflection phase control is presented to remove the phase tuning deficiency in conventional approach. The unit cell of the metasurface is a multiple resonance structure with two resonance poles and one resonance zero, capable of providing 360° reflection phase variation and active tuning within a finite frequency band. Linear reflection phase tuning can also be obtained. Theoretical analysis and simulation are presented and validated by experiment at microwave frequency. The proposed approach can be applied to many cases where fine and full phase tuning is needed, such as beam steering in reflectarray antennas. PMID:24162366

  20. Synthesis and evaluation of phase detectors for active bit synchronizers

    Science.gov (United States)

    Mcbride, A. L.

    1974-01-01

    Self-synchronizing digital data communication systems usually use active or phase-locked loop (PLL) bit synchronizers. The three main elements of PLL synchronizers are the phase detector, loop filter, and the voltage controlled oscillator. Of these three elements, phase detector synthesis is the main source of difficulty, particularly when the received signals are demodulated square-wave signals. A phase detector synthesis technique is reviewed that provides a physically realizable design for bit synchronizer phase detectors. The development is based upon nonlinear recursive estimation methods. The phase detector portion of the algorithm is isolated and analyzed.

  1. Antioxidant activity of Agaricus brasiliensis basidiocarps on different maturation phases

    OpenAIRE

    Francielly Mourão; Suzana Harue Umeo; Orlando Seiko Takemura; Giani Andrea Linde; Nelson Barros Colauto

    2011-01-01

    Different maturation phases of basidiocarp could affect the bioactivity and concentration of some active substances. A. brasiliensis Wasser et al.(A. blazei Murrill) has shown antitumor activity that could be related to the antioxidant activity. However there is no information of the best basidiocarp maturation phase for extracting antioxidant substances in order to determine the moment of harvesting in mushroom cultivation. The objective of this work was to evaluate the antioxidant activity ...

  2. Antioxidant Activity of Agaricus brasiliensis Basidiocarps on Different Maturation Phases

    OpenAIRE

    Mourão, Francielly; Harue Umeo, Suzana; Seiko Takemura, Orlando; Andrea Linde, Giani; Barros Colauto, Nelson

    2011-01-01

    Different maturation phases of basidiocarp could affect the bioactivity and concentration of some active substances. A. brasiliensis Wasser et al. (A. blazei Murrill) has shown antitumor activity that could be related to the antioxidant activity. However there is no information of the best basidiocarp maturation phase for extracting antioxidant substances in order to determine the moment of harvesting in mushroom cultivation. The objective of this work was to evaluate the antioxidant activity...

  3. Competing dynamic phases of active polymer networks

    Science.gov (United States)

    Freedman, Simon; Banerjee, Shiladitya; Dinner, Aaron R.

    Recent experiments on in-vitro reconstituted assemblies of F-actin, myosin-II motors, and cross-linking proteins show that tuning local network properties can changes the fundamental biomechanical behavior of the system. For example, by varying cross-linker density and actin bundle rigidity, one can switch between contractile networks useful for reshaping cells, polarity sorted networks ideal for directed molecular transport, and frustrated networks with robust structural properties. To efficiently investigate the dynamic phases of actomyosin networks, we developed a coarse grained non-equilibrium molecular dynamics simulation of model semiflexible filaments, molecular motors, and cross-linkers with phenomenologically defined interactions. The simulation's accuracy was verified by benchmarking the mechanical properties of its individual components and collective behavior against experimental results at the molecular and network scales. By adjusting the model's parameters, we can reproduce the qualitative phases observed in experiment and predict the protein characteristics where phase crossovers could occur in collective network dynamics. Our model provides a framework for understanding cells' multiple uses of actomyosin networks and their applicability in materials research. Supported by the Department of Defense (DoD) through the National Defense Science & Engineering Graduate Fellowship (NDSEG) Program.

  4. Consequences of abnormal CDK activity in S phase.

    Science.gov (United States)

    Anda, Silje; Rothe, Christiane; Boye, Erik; Grallert, Beáta

    2016-01-01

    Cyclin Dependent Kinases (CDKs) are important regulators of DNA replication. In this work we have investigated the consequences of increasing or decreasing the CDK activity in S phase. To this end we identified S-phase regulators of the fission yeast CDK, Cdc2, and used appropriate mutants to modulate Cdc2 activity. In fission yeast Mik1 has been thought to be the main regulator of Cdc2 activity in S phase. However, we find that Wee1 has a major function in S phase and thus we used wee1 mutants to investigate the consequences of increased Cdc2 activity. These wee1 mutants display increased replication stress and, particularly in the absence of the S-phase checkpoint, accumulate DNA damage. Notably, more cells incorporate EdU in a wee1(-) strain as compared to wildtype, suggesting altered regulation of DNA replication. In addition, a higher number of cells contain chromatin-bound Cdc45, an indicator of active replication forks. In addition, we found that Cdc25 is required to activate Cdc2 in S phase and used a cdc25 mutant to explore a situation where Cdc2 activity is reduced. Interestingly, a cdc25 mutant has a higher tolerance for replication stress than wild-type cells, suggesting that reduced CDK activity in S phase confers resistance to at least some forms of replication stress. PMID:26918805

  5. Administrative activities in the phase of preparation

    International Nuclear Information System (INIS)

    Details of the licensing procedure in the FRG: site selection, necessary documents for application, selection of a safety level for the plant in question, organization of the licensing authority, consultant and expert activities. (HP)

  6. A Novel Phase Sensitive Amplifier Based QPSK Regenerator Without Active Phase-Locking

    DEFF Research Database (Denmark)

    Kjøller, Niels-Kristian; Da Ros, Francesco; Røge, Kasper Meldgaard;

    2015-01-01

    We propose a novel QPSK regenerator scheme based on phase sensitive amplification of a pre-conditioned signal avoiding active phase-locking. Signal pre-conditioning is demonstrated experimentally with error-free (BER < 10-9) performance for a 10-Gbaud QPSK signal....

  7. Go-Lab Report on Implementation Activities Phase-B

    OpenAIRE

    Mavromanolakis, Georgios

    2015-01-01

    Implementation Phase-B covered the period from project month 25 to month 33, which corresponds to 1 Nov 2014 – 31 Jul 2015. During that 9-month period partners organized and conducted 80 implementation activities around the host countries. Of which, 35 were training workshops for teachers with 794 participants from 340 schools and 45 were activities with students with 1834 participants from 80 schools. The total summative results after Phase A and B are: 1184 teachers from 689 schools attende...

  8. Research for the energy turnaround. Phase transitions actively shape. Contributions

    International Nuclear Information System (INIS)

    The Annual Conference 2014 of the Renewable Energy Research Association was held in Berlin on 6 and 7 November 2014. This book documents the contributions of the conference on research for the energy turnaround, phase transitions actively shape. After an introduction and two contributions to the political framework, the contributions to the economic phases of the energy transition, the phase of the current turn, the phases of social energy revolution, the stages of heat turnaround (Waermewende), and the stages of the mobility turn deal with the stages of development of the energy system. Finally, the Research Association Renewable Energy is briefly presented.

  9. The micrometeoric input in the upper atmosphere. A comparison between model predictions and HPLA and meteor radars observations and AIM-CDE dust detections

    Science.gov (United States)

    Janches, Diego; Sparks, Jonathan; Johnson, Kyle; Poppe, Andrew; James, David; Fentzke, Jonathan; Palo, Scott; Horanyi, Mihaly

    It is now widely accepted that microgram extraterrestrial particles from the sporadic background are the major contributors of metals in the Mesosphere/Lower Thermosphere (MLT). It is also well established that this material gives rise to the upper atmospheric metallic and ion layers observed by radars and lidars. In addition, micrometeoroids are believed to be an important source for condensation nuclei (CN), the existence of which is a prerequisite for the formation of NLC and PMSE particles in the polar mesopause region. In order to understand how this flux gives rise to these atmospheric phenomena, accurate knowledge of the global meteoric input function (MIF) is critical. This function accounts for the annual and diurnal variations of meteor rates, global distribution, directionality, and velocity and mass distributions. Estimates of most of these parameters are still under investigation. In this talk, we present results of a detailed model of the diurnal, seasonal and geographical variability of the micrometeoric activity in the upper atmosphere. The principal goal of this effort is to construct a new and more precise sporadic MIF needed for the subsequent modeling of the atmospheric chemistry of meteoric material and the origin and formation of metal layers in the MLT. The model uses Monte Carlo simulation techniques and includes an accepted mass flux provided by six main known meteor sources (i.e. orbital families of dust) and a detailed modeling of the meteoroid atmospheric entry physics. We compare the model predictions with meteor head-echo observations using the 430 MHz Arecibo (AO) radar in Puerto Rico and the 450 MHz Advance Modular ISR in Poker Flat (PFISR), AK. The results indicate, that although the Earth's Apex centered source, thought to be composed mostly of dust from long period comets, is required to be only about ˜33% of dust in the Solar System at 1 AU, it accounts for 60 to 70% of the actual dust that ablates in the atmosphere. These

  10. Decommissioning activity of phase 2 in JRR-2

    Energy Technology Data Exchange (ETDEWEB)

    Kishimoto, Katsumi; Banba, Masao; Arigane, Kenji

    2000-10-01

    Japan Research Reactor No.2 (JRR-2), heavy water moderated and cooled tank type research reactor with maximum thermal power of 10MW, has been used over 36 years, and has permanently been shut down in Dec. 1996. Afterward, dismantling report has been submitted to the STA, and dismantling has been begun in 1997. Decommissioning of JRR-2 is planned in 11 years from 1997 to 2007, and the program is divided into 4 phases. Phase 1 had already been ended, and phase 2 is being executed in plan from Nov. 1998 to Mar. 2000. Phase 1, 2 are executed preparation of large scale dismantling in phase 3, 4. As main activity of phase 2, activities to keep reactor safely for a long period are being executed now. Isolation of cooling system as one of the activities has already been executed in first half of phase 2 ended by Mar. 1999. In this activity, cooling pipes and ducts connected to reactor have been cut off from reactor, and cutting parts of reactor side were sealed up. Additionally, it has also been achieved to lower dose equivalent rate in space just under core which had been high (max. 30mSv/h) to B.G. level by shielding {gamma} - ray from core tank. Reactor confinement as the other of the activities is being executed in second half of phase 2 executing now. In this activity, open parts of reactor will be sealed up by welding. Reactor will become condition to be able to keep safely for a long period by completing these activities. Transportation of the heavy water to Canada is being executing as another main activity of phase 2. The total heavy water (15m{sup 3}) after executing purification in second half of phase 2 is being transported on the sea in plan to arrive in Canada in Dec. 1999. Facilities control in JRR-2 will be simple by transfer of the heavy water contaminated by tritium, and safety will progress. (author)

  11. Recovery Efficiency Test Project: Phase 1, Activity report

    Energy Technology Data Exchange (ETDEWEB)

    Overbey, W.K. Jr.; Wilkins, D.W.; Keltch, B.; Saradji, B.; Salamy, S.P.

    1988-04-01

    This report is the second volume of the Recovery Efficiency Test Phase I Report of Activities. Volume 1 covered selection, well planning, drilling, coring, logging and completion operations. This volume reports on well testing activities, reclamation activities on the drilling site and access roads, and the results of physical and mechanical properties tests on the oriented core material obtained from a horizontal section of the well. 3 refs., 21 figs., 10 tabs.

  12. High Resolution Processing with an Active Phased Array SAR

    NARCIS (Netherlands)

    Nijenboer, F.J.; Otten, M.P.G.

    1999-01-01

    The Dutch PHARUS system is a polarimetric active phased array SAR capable of performing advanced SAR modes. Advanced SAR modes that are being investigated are: spotlight SAR, sliding spotlight SAR, stepped frequency SAR and interferometric SAR. The flight experiments and automatic beam steering impl

  13. Three Phase Bone Scintigraphy in Active and Inactive Osteomyelitis

    International Nuclear Information System (INIS)

    To Appreciate the value of bone scintigraphy in determination of the bony infection, we performed three phase bone scintigraphy in 34 cases of osteomyelitis of extremities prospectively. They were clinically inactive in 11 and active in 23 cases. We confirmed the active osteomyelitis by operation or aspiration within one week after scintigraphy. Perfusion, blood pool and delayed images were analyzed respectively and compared with the plain roentgenograms. All 23 active lesions showed diffusely increased perfusion in affected limbs. The areas of the increased activities on blood pool images were larger than or similar to those on delayed images in 17 cases (73.9%) with active osteomyelitis and smaller in 6 cases (26.1%). 5 of the latter 6 cases showed definite soft tissue activities on blood pool images. In inactive cases bone scintigrams were completely normal in 4 cases. Two of those were normal on plain films and remaining two showed mild focal bony sclerosis. Among 7 inactive lesions, perfusion was normal in 2 cases, diffusely increased in 4 cases and diffusely decreased in 1 case. 6 of these 7 cases showed increased activities both on blood pool and delayed images and the areas of increased activities on blood pool images didn't exceed those on delayed images. Bony sclerosis was noted on plain films in those 7 inactive lesions and the extent of the sclerosis correlated well to delayed images. Large blood pool activity was characteristics of active osteomyelitis. Normal three phase bone scintigram may indicate the time to terminate the treatment, but increased activity on perfusion and blood pool scans is not absolute indication of active lesion if the extent of the lesion on the blood pool image is smaller than that on delayed image and if no definite soft tissue activity is noted on perfusion and blood pool images in clinically inactive patient.

  14. Gamma power is phase-locked to posterior alpha activity.

    Directory of Open Access Journals (Sweden)

    Daria Osipova

    Full Text Available Neuronal oscillations in various frequency bands have been reported in numerous studies in both humans and animals. While it is obvious that these oscillations play an important role in cognitive processing, it remains unclear how oscillations in various frequency bands interact. In this study we have investigated phase to power locking in MEG activity of healthy human subjects at rest with their eyes closed. To examine cross-frequency coupling, we have computed coherence between the time course of the power in a given frequency band and the signal itself within every channel. The time-course of the power was calculated using a sliding tapered time window followed by a Fourier transform. Our findings show that high-frequency gamma power (30-70 Hz is phase-locked to alpha oscillations (8-13 Hz in the ongoing MEG signals. The topography of the coupling was similar to the topography of the alpha power and was strongest over occipital areas. Interestingly, gamma activity per se was not evident in the power spectra and only became detectable when studied in relation to the alpha phase. Intracranial data from an epileptic subject confirmed these findings albeit there was slowing in both the alpha and gamma band. A tentative explanation for this phenomenon is that the visual system is inhibited during most of the alpha cycle whereas a burst of gamma activity at a specific alpha phase (e.g. at troughs reflects a window of excitability.

  15. Phase-Transfer Activation of Transition Metal Catalysts.

    Science.gov (United States)

    Tuba, Robert; Xi, Zhenxing; Bazzi, Hassan S; Gladysz, John A

    2015-11-01

    With metal-based catalysts, it is quite common that a ligand (L) must first dissociate from a catalyst precursor (L'n M-L) to activate the catalyst. The resulting coordinatively unsaturated active species (L'n M) can either back react with the ligand in a k-1 step, or combine with the substrate in a k2 step. When dissociation is not rate determining and k-1 [L] is greater than or comparable to k2 [substrate], this slows the rate of reaction. By introducing a phase label onto the ligand L and providing a suitable orthogonal liquid or solid phase, dramatic rate accelerations can be achieved. This phenomenon is termed "phase-transfer activation". In this Concept, some historical antecedents are reviewed, followed by successful applications involving fluorous/organic and aqueous/organic liquid/liquid biphasic catalysis, and liquid/solid biphasic catalysis. Variants that include a chemical trap for the phase-labeled ligands are also described. PMID:26338471

  16. Quantitative phase imaging technologies to assess neuronal activity (Conference Presentation)

    Science.gov (United States)

    Thouvenin, Olivier; Fink, Mathias; Boccara, Claude

    2016-03-01

    Active neurons tends to have a different dynamical behavior compared to resting ones. Non-exhaustively, vesicular transport towards the synapses is increased, since axonal growth becomes slower. Previous studies also reported small phase variations occurring simultaneously with the action potential. Such changes exhibit times scales ranging from milliseconds to several seconds on spatial scales smaller than the optical diffraction limit. Therefore, QPI systems are of particular interest to measure neuronal activity without labels. Here, we report the development of two new QPI systems that should enable the detection of such activity. Both systems can acquire full field phase images with a sub nanometer sensitivity at a few hundreds of frames per second. The first setup is a synchronous combination of Full Field Optical Coherence Tomography (FF-OCT) and Fluorescence wide field imaging. The latter modality enables the measurement of neurons electrical activity using calcium indicators. In cultures, FF-OCT exhibits similar features to Digital Holographic Microscopy (DHM), except from complex computational reconstruction. However, FF-OCT is of particular interest in order to measure phase variations in tissues. The second setup is based on a Quantitative Differential Interference Contrast setup mounted in an epi-illumination configuration with a spectrally incoherent illumination. Such a common path interferometer exhibits a very good mechanical stability, and thus enables the measurement of phase images during hours. Additionally, such setup can not only measure a height change, but also an optical index change for both polarization. Hence, one can measure simultaneously a phase change and a birefringence change.

  17. Activity of Catalyst for Liquid Phase Methanol Synthesis

    Institute of Scientific and Technical Information of China (English)

    WANGYuefa; JanezLevec

    2002-01-01

    The effects of reduction procedure, reaction temperature and composition of feed gas on the activity of a CuO-ZnO-Al2O3 catalyst for liquid phase methanol synthesis were studied. An optimized procedure different from conventional ones was developed to obtain higher activity and better stability of the catalyst. Both CO and CO2 in the feed gas were found to be necessary to maintain the activity of catalyst in the synthesis process. Reaction temperature was limited up to 523K, otherwise the catalyst will be deactivated rapidly. Experimental results show that the catalyst deactivation is caused by sintering and fouling, and the effects of CO and CO2 on the catalyst activity are also investigated. The experimental results indicate that the formation of water in the methanol synthesis is negligible when the feed gas contains both CO and CO2. The mechanism for liquid-phase methanol synthesis was discussed and it differed slightly from that for gas-phase synthesis.

  18. Electrocatalytic activity of ordered intermetallic phases for fuel cell applications.

    Science.gov (United States)

    Casado-Rivera, Emerilis; Volpe, David J; Alden, Laif; Lind, Cora; Downie, Craig; Vázquez-Alvarez, Terannie; Angelo, Antonio C D; DiSalvo, Francis J; Abruña, Héctor D

    2004-03-31

    The electrocatalytic activities of a wide range of ordered intermetallic phases toward a variety of potential fuels have been studied, and results have been compared to those of a pure polycrystalline platinum (Pt(pc)) electrode. A significant number of the ordered intermetallic phases exhibited enhanced electrocatalytic activity when compared to that of Pt, in terms of both oxidation onset potential and current density. The PtBi, PtIn, and PtPb ordered intermetallic phases appeared to be the most promising electrocatalysts tested thus far for fuel cell applications. PtPb, in particular, showed an onset potential that was 100 mV less positive and a peak current density approximately 40 times higher than those observed for Pt in the case of methanol oxidation. The ability to control the geometric and electronic structures of the electrocatalytic material by using ordered intermetallic phases has been shown to be a promising direction of inquiry in the search for superior electrocatalysts for fuel cell applications. PMID:15038758

  19. Active cancellation of probing in linear dipole phased array

    CERN Document Server

    Singh, Hema; Jha, Rakesh Mohan

    2015-01-01

    In this book, a modified improved LMS algorithm is employed for weight adaptation of dipole array for the generation of beam pattern in multiple signal environments. In phased arrays, the generation of adapted pattern according to the signal scenario requires an efficient adaptive algorithm. The antenna array is expected to maintain sufficient gain towards each of the desired source while at the same time suppress the probing sources. This cancels the signal transmission towards each of the hostile probing sources leading to active cancellation. In the book, the performance of dipole phased array is demonstrated in terms of fast convergence, output noise power and output signal-to-interference-and noise ratio. The mutual coupling effect and role of edge elements are taken into account. It is established that dipole array along with an efficient algorithm is able to maintain multilobe beamforming with accurate and deep nulls towards each probing source. This work has application to the active radar cross secti...

  20. Antineoplasic activity of Agaricus brasiliensis basidiocarps on different maturation phases

    OpenAIRE

    Mourão, Francielly; Linde, Giani Andrea; Messa, Valdeci; da Cunha Júnior, Paulo Luiz; da Silva, Aristeu Vieira; da Eira, Augusto Ferreira; Colauto, Nelson Barros

    2009-01-01

    The fungus Agaricus brasiliensis is a Basidiomycete studied because of its immunomodulation and/or antitumor substances. The objective of this study was to verify the Agaricus brasiliensis antineoplasic activity in vivo on different basidiocarp maturation phases on Sarcoma 180 cells implanted in mice. Sarcoma cells were implanted in mice and after seven days mice were divided in three groups. The first group was treated with saline solution, the second group was treated with closed basidiocar...

  1. Collective versus hub activation of epidemic phases on networks

    CERN Document Server

    Ferreira, Silvio C; Pastor-Satorras, Romualdo

    2015-01-01

    We consider a general criterion to discern the nature of the threshold in epidemic models on scale-free (SF) networks. Comparing the epidemic lifespan of the nodes with largest degrees with the infection time between them, we propose a general dual scenario, in which the epidemic transition is either ruled by a hub activation process, leading to a null threshold in the thermodynamic limit, or given by a collective activation process, corresponding to a standard phase transition with a finite threshold. We validate the proposed criterion applying it different to epidemic models, with waning immunity or heterogeneous infection rates.

  2. Phase separation of biphasic mixture of active Janus colloids

    Science.gov (United States)

    Yan, Jing; Han, Ming; Luijten, Erik; Granick, Steve

    2014-03-01

    Recently there is a surge of interest in the phase behavior of active matter in which building blocks display self-propelling motion. Although much has been known from theory and simulation, experimental examples are very rare. Specifically, the epitomic problem of a binary mixture of active matter defies any experiment or theory so far. Here we present an experimental realization of binary mixture of particles, which only acquires activity when they collisionally interact with the opposite kind. We used a system in which the only difference in the two particles is the phase in their cyclic motion, precluding any artifact due to difference in interparticle potential. We observe phenomena strikingly similar to spinodal decomposition of molecular system, in addition to new features due to the nonequilibrium nature of the system. We derived a general, effective Flory-Huggins theory for spinodal decomposition of bicomponent active system, and rationalized the 1/3 power law growth of the domain size in regions where thermodynamic analogy is valid. The system also presents a plethora of nonequilibrium phenomena such as critical fluctuation, lane formation, and dynamic absorbing state in different parameter space.

  3. Two-phase flow measurement by pulsed neutron activation techniques

    International Nuclear Information System (INIS)

    The Pulsed Neutron Activation (PNA) technique for measuring the mass flow velocity and the average density of two-phase mixtures is described. PNA equipment can be easily installed at different loops, and PNA techniques are non-intrusive and independent of flow regimes. These features of the PNA technique make it suitable for in-situ measurement of two-phase flows, and for calibration of more conventional two-phase flow measurement devices. Analytic relations governing the various PNA methods are derived. The equipment and procedures used in the first air-water flow measurement by PNA techniques are discussed, and recommendations are made for improvement of future tests. In the present test, the mass flow velocity was determined with an accuracy of 2%, and average densities were measured down to 0.08 g/cm3 with an accuracy of 0.04 g/cm3. Both the accuracy of the mass flow velocity measurement and the lower limit of the density measurement are functions of the injected activity and of the total number of counts. By using a stronger neutron source and a larger number of detectors, the measurable density can be decreased by a factor of 12 to .007 g/cm3 for 12.5 cm pipes, and to even lower ranges for larger pipes

  4. Substrate integrated ferrite phase shifters and active frequency selective surfaces

    CERN Document Server

    Cahill, B M

    2002-01-01

    There are two distinct parts to this thesis; the first investigates the use of ferrite tiles in the construction of printed phase shifting transmission lines, culminating in the design of two compact electromagnetic controlled beam steered patch and slot antenna arrays. The second part investigates the use of active frequency selective surfaces (AFSS), which are later used to cover a uPVC constructed enclosure. Field intensity measurements are taken from within the enclosure to determine the dynamic screening effectiveness. Trans Tech G-350 Ferrite is investigated to determine its application in printed microstrip and stripline phase shifting transmission lines. 50-Ohm transmission lines are constructed using the ferrite tile and interfaced to Rogers RT Duroid 5870 substrate. Scattering parameter measurements are made under the application of variable magnetic fields to the ferrite. Later, two types of planar microwave beam steering antennas are constructed. The first uses the ferrites integrated into the Dur...

  5. An active interferometer-stabilization scheme with linear phase control

    DEFF Research Database (Denmark)

    Vardhan Krishnamachari, Vishnu; Andresen, Esben Ravn; Potma, Eric Olaf

    2006-01-01

    We report a simple and robust computer-based active interferometer stabilization scheme which does not require modulation of the interfering beams and relies on an error signal which is linearly related to the optical path difference. In this setup, a non-collinearly propagating reference laser...... beam stabilizes the interference output of the laser light propagating collinearly through the interferometer. This stabilization scheme enables adjustable phase control with 20 ms switching times in the range from 0.02π radians to 6π radians at 632.8 nm....

  6. Relationship between geomagnetic classes’ activity phases and their occurrence during the sunspot cycle

    Directory of Open Access Journals (Sweden)

    Frédéric Ouattara

    2009-06-01

    Full Text Available Four well known geomagnetic classes of activity such as quiet days activity, fluctuating activity, recurrent activity
    and shock activity time occurrences have been determined not only by using time profile of sunspot number
    Rz but also by using aa index values.
    We show that recurrent wind stream activity and fluctuating activity occur in opposite phase and slow solar wind
    activity during minimum phase and shock activity at the maximum phase.
    It emerges from this study that fluctuating activity precedes the sunspot cycle by π/2 and the latter also precedes
    recurrent activity by π/2. Thus in the majority the activities do not happen at random; the sunspot cycle starts
    with quiet days activity, continues with fluctuating activity and during its maximum phase arrives shock activity.
    The descending phase is characterized by the manifestation of recurrent wind stream activity.

  7. Advanced nonlinear control of three phase series active power filter

    Directory of Open Access Journals (Sweden)

    Abouelmahjoub Y.

    2014-01-01

    Full Text Available The problem of controlling three-phase series active power filter (TPSAPF is addressed in this paper in presence of the perturbations in the voltages of the electrical supply network. The control objective of the TPSAPF is twofold: (i compensation of all voltage perturbations (voltage harmonics, voltage unbalance and voltage sags, (ii regulation of the DC bus voltage of the inverter. A controller formed by two nonlinear regulators is designed, using the Backstepping technique, to provide the above compensation. The regulation of the DC bus voltage of the inverter is ensured by the use of a diode bridge rectifier which its output is in parallel with the DC bus capacitor. The Analysis of controller performances is illustrated by numerical simulation in Matlab/Simulink environment.

  8. Substrate integrated ferrite phase shifters and active frequency selective surfaces

    International Nuclear Information System (INIS)

    There are two distinct parts to this thesis; the first investigates the use of ferrite tiles in the construction of printed phase shifting transmission lines, culminating in the design of two compact electromagnetic controlled beam steered patch and slot antenna arrays. The second part investigates the use of active frequency selective surfaces (AFSS), which are later used to cover a uPVC constructed enclosure. Field intensity measurements are taken from within the enclosure to determine the dynamic screening effectiveness. Trans Tech G-350 Ferrite is investigated to determine its application in printed microstrip and stripline phase shifting transmission lines. 50-Ohm transmission lines are constructed using the ferrite tile and interfaced to Rogers RT Duroid 5870 substrate. Scattering parameter measurements are made under the application of variable magnetic fields to the ferrite. Later, two types of planar microwave beam steering antennas are constructed. The first uses the ferrites integrated into the Duroid as microstrip lines with 3 patch antennas as the radiating elements. The second uses stripline transmission lines, with slot antennas as the radiating sources etched into the ground plane of the triplate. Beam steering is achieved by the application of an external electromagnet. An AFSS is constructed by the interposition of PIN diodes into a dipole FSS array. Transmission response measurements are then made for various angles of electromagnetic wave incidence. Two states of operation exist: when a current is passed through the diodes and when the diodes are switched off. These two states form a high pass and band stop space filter respectively. An enclosure covered with the AFSS is constructed and externally illuminated in the range 2.0 - 2.8GHz. A probe antenna inside the enclosure positioned at various locations through out the volume is used to establish the effective screening action of the AFSS in 3 dimensional space. (author)

  9. Plans for the next phase of CORDEX activities

    Science.gov (United States)

    Giorgi, Filippo; Gutowski, William

    2016-04-01

    Ensembles of Regional Climate Model (RCM) projections have been completed under the protocol of the first phase of the COordinated Regional Downscaling EXperiment (CORDEX, Giorgi et al. 2009) over most CORDEX domains. As a result of these activities a number of scientific issues have emerged, which provide the basis for discussion of the next phase of the CORDEX program. Among such issues are a clearer identification and quantification of the added value of the use of RCMs, the development and use of a new generation of very high resolution (change and aerosols) and a better integration of empirical/statistical downscaling within the CORDEX framework. A large inhomogeneity was also noted across different CORDEX regional efforts, with some domains (e.g. EURO-CORDEX, AFRICA-CORDEX and MED-CORDEX) being covered by large ensembles and others by much more sparse experiment matrices. This has limited the use of CORDEX results in international programs such as the Intergovernmental Panel on Climate Change (IPCC). Two avenues are being discussed in order to address these issues. The first is to produce a homogeneous set of higher resolution projections (10-20 km) across all or most CORDEX domains using a core set of RCMs downscaling a core set of GCMs. The second is to develop and implement a set of "Flagship Pilot Studies (FPSs)" over sub-regions of interest aimed at addressing specific scientific questions (e.g. added value and convection-permitting simulations, intercomparison of different downscaling approaches, land-use and aerosol effects). In this presentation we will describe the status of the discussion and plans for these new CORDEX initiatives, which will be likely finalized at the upcoming third Pan-CORDEX conference (ICRC-CORDEX 2016) to be held in Stockholm on 17-10 May, 2016. Giorgi F, Jones C, Asrar G, 2009. Addressing climate information needs at the regional level: the CORDEX framework. WMO Bulletin, 58:175-183.

  10. Role for non-proteolytic control of M-phase-promoting factor activity at M-phase exit.

    Directory of Open Access Journals (Sweden)

    Vincenzo D'Angiolella

    Full Text Available M-phase Promoting Factor (MPF; the cyclin B-cdk 1 complex is activated at M-phase onset by removal of inhibitory phosphorylation of cdk1 at thr-14 and tyr-15. At M-phase exit, MPF is destroyed by ubiquitin-dependent cyclin proteolysis. Thus, control of MPF activity via inhibitory phosphorylation is believed to be particularly crucial in regulating transition into, rather than out of, M-phase. Using the in vitro cell cycle system derived form Xenopus eggs, here we show, however, that inhibitory phosphorylation of cdk1 contributes to control MPF activity during M-phase exit. By sampling extracts at very short intervals during both meiotic and mitotic exit, we found that cyclin B1-associated cdk1 underwent transient inhibitory phosphorylation at tyr-15 and that cyclin B1-cdk1 activity fell more rapidly than the cyclin B1 content. Inhibitory phosphorylation of MPF correlated with phosphorylation changes of cdc25C, the MPF phosphatase, and physical interaction of cdk1 with wee1, the MPF kinase, during M-phase exit. MPF down-regulation required Ca(++/calmodulin-dependent kinase II (CaMKII and cAMP-dependent protein kinase (PKA activities at meiosis and mitosis exit, respectively. Treatment of M-phase extracts with a mutant cyclin B1-cdk1AF complex, refractory to inhibition by phosphorylation, impaired binding of the Anaphase Promoting Complex/Cyclosome (APC/C to its co-activator Cdc20 and altered M-phase exit. Thus, timely M-phase exit requires a tight coupling of proteolysis-dependent and proteolysis-independent mechanisms of MPF inactivation.

  11. Final synthesis of Sarnet (Phase 1) corium activities

    International Nuclear Information System (INIS)

    Within the SARNET Severe Accident Research Network of excellence, the Corium topic covers all the behaviour of corium (mixture formed by the molten materials arising from a postulated nuclear reactor severe accident) from early phase of core degradation to in or ex-vessel corium recovery with the exception of corium interaction with water, direct containment heating and fission product release. The Corium topic regroups in three work packages the critical mass of competence to improve significantly the corium behaviour knowledge. The spirit of the SARNET networking is to share the knowledge, the facilities and the simulation tools for severe accidents, so to reach a better efficiency and to rationalize the R and D effort at European level. Extensive benchmarking has been launched in most of the areas of research. These benchmarks were mainly dedicated to the recalculation of analytical experiments, integral experiments or reactor applications. Eventually, all the knowledge will be accumulated in the ASTEC severe accident simulation code through physical model improvements and extension of validation database. This report summarizes the progress that has been achieved in the frame of the networking activities for the four and half years of the FP6 project. (authors)

  12. MATHEMATICAL OPTIMIZATION METHODS TO ESTABLISH ACTIVE PHASES ON HETEROGENEOUS CATALYSIS: CASE OF BULK TRANSITION METAL SULPHIDES

    Directory of Open Access Journals (Sweden)

    Iván Machín

    2015-03-01

    Full Text Available This paper presents a set of procedures based on mathematical optimization methods to establish optimal active sulphide phases with higher HDS activity. This paper proposes a list of active phases as a guide for orienting the experimental work in the search of new catalysts that permit optimize the HDS process. Studies in this paper establish Co-S, Cr-S, Nb-S and Ni-S systems have the greatest potential to improve HDS activity.

  13. Correlating oxygen vacancies and phase ratio/interface with efficient photocatalytic activity in mixed phase TiO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Verma, Ranjana [Solar Energy Material Laboratory, Department of Energy, Tezpur University, Tezpur, Assam (India); Samdarshi, S.K., E-mail: drsksamdarshi@rediffmail.com [Centre for Energy Engineering, Central University of Jharkhand, Ranchi, Jharkhand (India)

    2015-04-25

    Graphical abstract: The correlation of interfacial behavior and oxygen vacancies in mixed phase titania nanoparticles on their performance as photocatalyst has been investigated to explain the impact of photoactivity under UV and visible irradiation compared to pristine counterparts. The defects at the junction effectively reduce the band gap as well decrease the carrier recombination to enhance the photocatalytic activity. - Highlights: • Pristine and mixed phases (A/R ratio) TiO{sub 2} synthesized by sol gel route. • Photoactivity variation has been correlated with the changes in the phase ratio. • Enhanced UV and visible activity attributable to oxygen vacancy present at the interface. • Role of A/R ratio and oxygen vacancy in the photoactivity of mixed TiO{sub 2} depicted through a model. - Abstract: The photocatalytic activity is a result of the synergy of a succession of phenomena-photogeneration, separation, and participation of the charge carriers in redox reaction at the catalyst surface. While the extent of photogeneration is assessable in terms of absorption spectrum (band gap), the redox reaction can be correlated to specific surface area. However the respective change in the photocatalytic activity has not been rationally and consistently correlated with the above mentioned parameters. A satisfactory explanation of suppression of recombination based on separation of carriers due to differential mobility/diffusivity in the material phase(s) and/or intrinsic potential barrier exists but its correlation with common identifiable parameter/characteristics is still elusive. This paper attempts to address this issue by correlating the carrier separation with the phase ratio (phase interface) in mixed phase titania and generalizing it with the presence of oxygen vacancy at the phase interface. It essentially appears to complete the quest for identifiable parameters in the sequence of phenomena, which endow a photocatalyst with an efficient activity

  14. Polymerisation of activated RNA in eutectic ice phases

    DEFF Research Database (Denmark)

    Dörr, Mark; Maurer, Sarah Elisabeth; Monnard, Pierre-Alain

    (“cooperative sequences”) or degrading (“parasitic sequences”) the RNA population. These eutectic phases in water-ice are plausible prebiotic micro-environments that should help to overcome the dilution problem in origin of life scenarios. They might have supported the production of libraries...

  15. Four-Phase Oscillators Employing Two Active Elements

    OpenAIRE

    V. Biolkova; J. Bajer; Biolek, D.

    2011-01-01

    Two novel four-phase voltage-output oscillators are proposed. These circuits can also be utilized as quadrature oscillators with floating outputs. Each oscillator employs two DO-CIBA (Differential Output- Current Inverter Buffered Amplifier), two grounded capacitors, and four or three resistors. Independent control of the oscillation frequency (OF) and oscillation condition is practicable in both oscillators. Real measurements on the oscillator specimens confirm the ability of easy OF control...

  16. A predictive control algorithm for an active three-phase power filter

    Directory of Open Access Journals (Sweden)

    R.V. Vlasenko

    2014-09-01

    Full Text Available The paper deals with grid connection circuits for active filters, structures of active power filter control systems, and methods based on full capacity components determination. The existing structures of active power filter control and control algorithm adjustment for valve commutation loss reduction are analyzed. A predictive control algorithm for an active three-phase power filter is introduced.

  17. A predictive control algorithm for an active three-phase power filter

    OpenAIRE

    R.V. Vlasenko; Bialobrzeski, O. V.

    2014-01-01

    The paper deals with grid connection circuits for active filters, structures of active power filter control systems, and methods based on full capacity components determination. The existing structures of active power filter control and control algorithm adjustment for valve commutation loss reduction are analyzed. A predictive control algorithm for an active three-phase power filter is introduced.

  18. Four-Phase Oscillators Employing Two Active Elements

    Directory of Open Access Journals (Sweden)

    V. Biolkova

    2011-04-01

    Full Text Available Two novel four-phase voltage-output oscillators are proposed. These circuits can also be utilized as quadrature oscillators with floating outputs. Each oscillator employs two DO-CIBA (Differential Output- Current Inverter Buffered Amplifier, two grounded capacitors, and four or three resistors. Independent control of the oscillation frequency (OF and oscillation condition is practicable in both oscillators. Real measurements on the oscillator specimens confirm the ability of easy OF control and extra low THD, which is less than 0.07%.

  19. Recovery Efficiency Test Project Phase 2 activity report, Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Overbey, W.K. Jr.; Salamy, S.P.; Locke, C.D.

    1989-02-01

    The purpose of Phase II operations of the Recovery Efficiency Test Project is to enhance the natural production of the well and evaluate the relative improvement as a function of the type of stimulation conducted. Another purpose is to compare the stimulated production performance of the horizontal well with vertical wells in the field. The objectives considered for Phase II operations and plans were: (1) Develop a rationale for a systematic approach to designing stimulations for the well. (2) Conduct a series of stimulations designed to optimize the fluids, injection rates, proppant volumes and general approach to stimulating a horizontal well with similar geologic conditions. (3) Develop and test a method or methods for determining the geometry of stimulation-induced fractures. (4) Conduct tests and analyze the results to determine the efficiency of stimulation operations. The technical approach pursued in developing plans to accomplish three objectives was to: (1) Review the data needs for all objectives and obtain that data first. (2) Identify the operating geologic, geomechanical, and reservoir parameters that need additional clarification or definition. (3) Investigate existing models which could be used to plan or evaluate stimulation on the well and the reservoir. (4) Plan for analysis and verification of models and approaches.

  20. Superfluid phase transition with activated velocity fluctuations: Renormalization group approach.

    Science.gov (United States)

    Dančo, Michal; Hnatič, Michal; Komarova, Marina V; Lučivjanský, Tomáš; Nalimov, Mikhail Yu

    2016-01-01

    A quantum field model that incorporates Bose-condensed systems near their phase transition into a superfluid phase and velocity fluctuations is proposed. The stochastic Navier-Stokes equation is used for a generation of the velocity fluctuations. As such this model generalizes model F of critical dynamics. The field-theoretic action is derived using the Martin-Siggia-Rose formalism and path integral approach. The regime of equilibrium fluctuations is analyzed within the perturbative renormalization group method. The double (ε,δ)-expansion scheme is employed, where ε is a deviation from space dimension 4 and δ describes scaling of velocity fluctuations. The renormalization procedure is performed to the leading order. The main corollary gained from the analysis of the thermal equilibrium regime suggests that one-loop calculations of the presented models are not sufficient to make a definite conclusion about the stability of fixed points. We also show that critical exponents are drastically changed as a result of the turbulent background and critical fluctuations are in fact destroyed by the developed turbulence fluctuations. The scaling exponent of effective viscosity is calculated and agrees with expected value 4/3.

  1. Activity mediated phase separation: Can we understand phase behavior of the nonequilibrium problem from an equilibrium approach?

    Science.gov (United States)

    Trefz, Benjamin; Das, Subir K.; Egorov, Sergei A.; Virnau, Peter; Binder, Kurt

    2016-04-01

    We present results for structure and dynamics of mixtures of active and passive particles, from molecular dynamics (MD) simulations and integral equation theory (IET) calculations, for a physically motivated model. The perfectly passive limit of the model corresponds to the phase-separating Asakura-Oosawa model for colloid-polymer mixtures in which, for the present study, the colloids are made self-propelling by introducing activity in accordance with the well known Vicsek model. Such activity facilitates phase separation further, as confirmed by our MD simulations and IET calculations. Depending upon the composition of active and passive particles, the diffusive motion of the active species can only be realized at large time scales. Despite this, we have been able to construct an equilibrium approach to obtain the structural properties of such inherently out-of-equilibrium systems. In this method, effective inter-particle potentials were constructed via IET by taking structural inputs from the MD simulations of the active system. These potentials in turn were used in passive MD simulations, results from which are observed to be in fair agreement with the original ones.

  2. Phase Behavior of Active Swimmers in Depletants: Molecular Dynamics and Integral Equation Theory

    Science.gov (United States)

    Das, Subir K.; Egorov, Sergei A.; Trefz, Benjamin; Virnau, Peter; Binder, Kurt

    2014-05-01

    We study the structure and phase behavior of a binary mixture where one of the components is self-propelling in nature. The interparticle interactions in the system are taken from the Asakura-Oosawa model for colloid-polymer mixtures for which the phase diagram is known. In the current model version, the colloid particles are made active using the Vicsek model for self-propelling particles. The resultant active system is studied by molecular dynamics methods and integral equation theory. Both methods produce results consistent with each other and demonstrate that the Vicsek model-based activity facilitates phase separation, thus, broadening the coexistence region.

  3. Phase transition in PT symmetric active plasmonic systems

    CERN Document Server

    Mattheakis, M; Molina, M I; Tsironis, G P

    2015-01-01

    Surface plasmon polaritons (SPPs) are coherent electromagnetic surface waves trapped on an insulator-conductor interface. The SPPs decay exponentially along the propagation due to conductor losses, restricting the SPPs propagation length to few microns. Gain materials can be used to counterbalance the aforementioned losses. We provide an exact expression for the gain, in terms of the optical properties of the interface, for which the losses are eliminated. In addition, we show that systems characterized by lossless SPP propagation are related to PT symmetric systems. Furthermore, we derive an analytical critical value of the gain describing a phase transition between lossless and prohibited SPPs propagation. The regime of the aforementioned propagation can be directed by the optical properties of the system under scrutiny. Finally, we perform COMSOL simulations verifying the theoretical findings.

  4. Indirect control of a single-phase active power filter

    Directory of Open Access Journals (Sweden)

    Mihai CULEA

    2006-12-01

    Full Text Available The control of shunt active power filters using PWM inverters consists in generating a reference by separating, using different methods, the harmonics to be eliminated. The methods used are time-consuming and need dedicated control and signal processing equipments. To avoid these setbacks a new method is proposed in the paper. The active power filter is a current PWM rectifier with voltage output and with a capacitor on the DC side. The PWM rectifier is controlled so that the sum of its current and the load’s current is a sinusoid. The control block as well as simulation results are presented.

  5. A new method for calculating the activity of stable compound from binary phase diagram

    Institute of Scientific and Technical Information of China (English)

    CHEN Dengfu; DONG Lingyan; BAI Chenguang; LIU Qingcai; WANG Chuanjun

    2006-01-01

    A new method to calculate the activity of a stable compound in a binary phase diagram was presented and dis cussed. According to the formula for calculating activity from the binary phase diagram, the equilibrium constant can be calculated through the mass action principle after the activities of two pure components were computed respectively. Based on that, the activity of a stable compound can be easily obtained at last. The activity of the stable compound InSb is calculated in the In-Sb binary system by using this method. The result is well consistent with another calculation value.

  6. Spindle activity phase-locked to sleep slow oscillations.

    Science.gov (United States)

    Klinzing, Jens G; Mölle, Matthias; Weber, Frederik; Supp, Gernot; Hipp, Jörg F; Engel, Andreas K; Born, Jan

    2016-07-01

    The right hemisphere did not reveal any signs of a concurrent lateralization of spindle activity co-occurring with these SOs. Our data are consistent with the concept of the neocortical SO exerting top-down control over thalamic spindle generation. However, they call into question the notion that SOs locally coordinate spindles and thereby inform spindle-related memory processing. PMID:27103135

  7. Creating of highly active calcium-silicate phases for application in endodontics

    OpenAIRE

    Čolović B.; Jokanović V.; Jović N.

    2013-01-01

    The synthesis of active silicate phases by combined sol gel and high-temperature selfpropagating wave method, is described in this paper. They show a significant decrease of setting time and good mechanical properties, which are very important for its potential application in endodontic practice. Particularly, process of hydration of calcium silicate phases is carefully analyzed, from the aspect of phase changes during their soaking in water for 1, 3, 7 and...

  8. Regulation of phase I and phase II steroid metabolism enzymes by PPARα activators

    International Nuclear Information System (INIS)

    Peroxisome proliferators (PP) are a large class of structurally diverse chemicals that mediate their effects in the liver mainly through the peroxisome proliferator-activated receptor α (PPARα). Exposure to some PP results in alterations of steroid levels that may be mechanistically linked to adverse effects in reproductive organs. We hypothesized that changes in steroid levels after PP exposure are due to alterations in the levels of P450 enzymes that hydroxylate testosterone and estrogen. In testosterone hydroxylase assays, exposure to the PP, WY-14,643 (WY), gemfibrozil or di-n-butyl phthalate (DBP) led to compound-specific increases in 6β and 16β-testosterone and androstenedione hydroxylase activities and decreases in 16α, 2α-hydroxylase activities by all three PP. The decreases in 16α and 2α-testosterone hydroxylase activity can be attributed to a 2α and 16α- testosterone hydroxylase, CYP2C11, which we previously showed was dramatically down-regulated in these same tissues (Corton et al., 1998; Mol. Pharmacol. 54, 463-473). To explain the increases in 6β- and 16β-testosterone hydroxylase activities, we examined the expression of P450 family members known to carry out these functions. Alterations in the 6β-testosterone hydroxylases CYP3A1, CYP3A2 and the 16β-testosterone hydroxylase, CYP2B1 were observed after exposure to some PP. The male-specific estrogen sulfotransferase was down-regulated in rat liver after exposure to all PP. The mouse 6β-testosterone hydroxylase, Cyp3a11 was down-regulated by WY in wild-type but not PPARα-null mice. In contrast, DEHP increased Cyp3a11 in both wild-type and PPARα-null mice. These studies demonstrate that PP alter the expression and activity of a number of enzymes which regulate levels of sex steroids. The changes in these enzymes may help explain why exposure to some PP leads to adverse effects in endocrine tissues that produce or are the targets of sex hormones

  9. Bolivia Country Program Phase II : Rural Energy and Energy Efficiency Report on Operational Activities

    OpenAIRE

    World Bank

    2005-01-01

    The ESMAP Bolivia country program phase II (ESMAP II) consisted of two main components : rural energy (RE) and energy efficiency (EE). The activities under these components were designated to help the government consolidate the achievements of phase I and make further progress in : a) strengthen the government's capacity to ensure sustainable development of RE and EE; b) create incentives ...

  10. Common oscillatory modes in geomagnetic activity and climate variability and their phase relations

    International Nuclear Information System (INIS)

    Complete text of publication follows. Oscillatory modes with period of approximately 8 years were detected in monthly time series of geomagnetic activity aa-index, North Atlantic Oscillation index and near-surface air temperature from several mid-latitude European locations. Instantaneous phases of the modes underwent synchronization analysis and their statistically significant phase coherence, beginning from 1950's, has been observed.

  11. Detecting Intermittent Steering Activity ; Development of a Phase-detection Algorithm

    NARCIS (Netherlands)

    Silva Peixoto de Aboim Chaves, H.M. da; Pauwelussen, J.J.A.; Mulder, M.; Paassen, M.M. van; Happee, R.; Mulder, M.

    2012-01-01

    Drivers usually maintain an error-neglecting control strategy (passive phase) in keeping their vehicle on the road, only to change to an error-correcting approach (active phase) when the vehicle state becomes inadequate. We developed an algorithm that is capable of detecting whether the driver is cu

  12. General Electric ATS program technical review: Phase 2 activities

    Energy Technology Data Exchange (ETDEWEB)

    Chance, T. [GE Power Generation, Schenectady, NY (United States); Smith, D. [GE Corporate Research & Development Center, Schenectady, NY (United States)

    1995-10-01

    In response to the industrial and utility objectives specified for the ATS, the GE Power Generation ATS Phase 2 Program consisted of a dual approach. These were (1) development of an Industrial ATS (aircraft engine based) led by GE Aircraft Engines, and (2) development of a Utility ATS which was already underway at GEPG. Both programs required the identification and resolution of critical technical issues. Both systems were studied in Tasks 3-7, and both have resulted in designs that meet all ATS goals. The Industrial ATS as defined (130 MW) did not meet projected market power size requirements, and emphasis has remained on the Utility ATS development. The design and testing effort has been focused on the MS7001H combined cycle gas turbine, as the next product evolution in GE Power Generation`s product line. Common technology derived from the ATS Program is also being incorporated into the 50 Hz version of the ATS utility machine designated as the MS9001H.

  13. Increased platelet activation in the chronic phase after cerebral ischemia and intracerebral hemorrhage

    NARCIS (Netherlands)

    F. van Kooten (Fop); G. Ciabattoni; P.J. Koudstaal (Peter Jan); D.W.J. Dippel (Diederik); C. Patrono

    1999-01-01

    textabstractBACKGROUND AND PURPOSE: Enhanced thromboxane (TX) biosynthesis has previously been reported in the acute phase after ischemic stroke. We investigated whether enhanced urinary excretion of 11-dehydro-TXB2, a noninvasive index of platelet activation, was prese

  14. Stability and phase transfer of catalytically active platinum nanoparticle suspensions

    Energy Technology Data Exchange (ETDEWEB)

    Sriram, Indira; Curtin, Alexandra E.; Chiaramonti, Ann N.; Cuchiaro, J. Hunter; Weidner, Andrew R.; Tingley, Tegan M.; Greenlee, Lauren F.; Jeerage, Kavita M., E-mail: jeerage@boulder.nist.gov [National Instrument of Standards and Technology, Applied Chemicals and Materials Division (United States)

    2015-05-15

    In this work, we present a robust synthesis protocol for platinum nanoparticles that yields a monomodal dispersion of particles that are approximately 100 nm in diameter. We determine that these particles are actually agglomerates of much smaller particles, creating a “raspberry” morphology. We demonstrate that these agglomerates are stable at room temperature for at least 8 weeks by dynamic light scattering. Furthermore, we demonstrate consistent electrocatalytic activity for methanol oxidation. Finally, we quantitatively explore the relationship between dispersion solvent and particle agglomeration; specifically, particles are found to agglomerate abruptly as solvent polarity decreases.

  15. Micromechanics and constitutive models for soft active materials with phase evolution

    Science.gov (United States)

    Wang, Binglian

    Soft active materials, such as shape memory polymers, liquid crystal elastomers, soft tissues, gels etc., are materials that can deform largely in response to external stimuli. Micromechanics analysis of heterogeneous materials based on finite element method is a typically numerical way to study the thermal-mechanical behaviors of soft active materials with phase evolution. While the constitutive models that can precisely describe the stress and strain fields of materials in the process of phase evolution can not be found in the databases of some commercial finite element analysis (FEA) tools such as ANSYS or Abaqus, even the specific constitutive behavior for each individual phase either the new formed one or the original one has already been well-known. So developing a computationally efficient and general three dimensional (3D) thermal-mechanical constitutive model for soft active materials with phase evolution which can be implemented into FEA is eagerly demanded. This paper first solved this problem theoretically by recording the deformation history of each individual phase in the phase evolution process, and adopted the idea of effectiveness by regarding all the new formed phase as an effective phase with an effective deformation to make this theory computationally efficient. A user material subroutine (UMAT) code based on this theoretical constitutive model has been finished in this work which can be added into the material database in Abaqus or ANSYS and can be easily used for most soft active materials with phase evolution. Model validation also has been done through comparison between micromechanical FEA and experiments on a particular composite material, shape memory elastomeric composite (SMEC) which consisted of an elastomeric matrix and the crystallizable fibre. Results show that the micromechanics and the constitutive models developed in this paper for soft active materials with phase evolution are completely relied on.

  16. Variability in AIRS CO2 during active and break phases of Indian summer monsoon.

    Science.gov (United States)

    Revadekar, J V; Ravi Kumar, K; Tiwari, Yogesh K; Valsala, Vinu

    2016-01-15

    Due to human activities, the atmospheric concentration of Carbon Dioxide (CO2) has been rising extensively since the Industrial Revolution. Indian summer monsoon (ISM) has a dominant westerly component from ocean to land with a strong tendency to ascend and hence may have role in CO2 distribution in lower and middle troposphere over Indian sub-continent. A substantial component of ISM variability arises from the fluctuations on the intra-seasonal scale between active and break phases which correspond to strong and weak monsoon circulation. In view of the above, an attempt is made in this study to examine the AIRS/AQUA satellite retrieved CO2 distribution in response to atmospheric circulation with focus on active and break phase. Correlation analysis indicates the increase in AIRS CO2 linked with strong monsoon circulation. Study also reveals that anomalous circulation pattern during active and break phase show resemblance with high and low values of AIRS CO2. Homogeneous monsoon regions of India show substantial increase in CO2 levels during active phase. Hilly regions of India show strong contrast in CO2 and vertical velocity during active and break phases. PMID:26476061

  17. OBJECTIVE EVALUATION OF CARDIAC AUTONOMIC ACTIVITY IN DIFFERENT PHASES OF MENSTRUAL CYCLE

    Directory of Open Access Journals (Sweden)

    Srujana

    2015-01-01

    Full Text Available A wide spectrum of biological function is regulated by the cyclic changes in estrogen and progesterone levels during regular menstrual cycle. However limited literature is available concerning the relationship of these hormones and cardiac autonomic activity. In the present study, we hypothesize that there would be heart rate variability during different phases of menstrual cycle, which can be attributed to the effect of ovarian steroids on cardiovascular function in women. The aim of the study is to compare the c ardiac autonomic activity in the different phases of menstrual cycle ( M enstrual, follicular and luteal phases using heart rate variability. The objective is to establish a physiological correlation between the cardiac autonomic activity and different phas es of menstrual cycle. The study was conducted in 48 regularly menstruating young female, of age group 18 - 30yrs, in the Upgraded Department of Physiology, Osmania medical college, from December 2011 to August 2013, using LABCHART software provided by ADLAB S. The power spectral analysis of HRV was used to calculate low frequency(LF , high frequency (HF component and their ratio (LF/HF during menstrual (2±1 days, follicular(11±1 day and luteal phases (20±1day from the first day of bleeding. Results showe d a significant increase was noted in low frequency component in luteal phase compared to follicular phase (p=0.000, whereas, a tendency for increase in high frequency component was observed in follicular phase (p=0.004. Furthermore, LF/HF was significan tly higher in luteal phase than in the follicular phase (p=0.000 indicating an increased sympathetic activity. The conclusion is regulation of autonomic tone is modified during menstrual cycle. The alteration in the balance of ovarian hormones might be re sponsible for these changes.

  18. Modest induction of phase 2 enzyme activity in the F-344 rat prostate

    Directory of Open Access Journals (Sweden)

    Brooks James D

    2006-03-01

    Full Text Available Abstract Background Prostate cancer is the most commonly diagnosed malignancy in men and is thought to arise as a result of endogenous oxidative stress in the face of compromised carcinogen defenses. We tested whether carcinogen defense (phase 2 enzymes could be induced in the prostate tissues of rats after oral feeding of candidate phase 2 enzyme inducing compounds. Methods Male F344 rats were gavage fed sulforaphane, β-naphthoflavone, curcumin, dimethyl fumarate or vehicle control over five days, and on the sixth day, prostate, liver, kidney and bladder tissues were harvested. Cytosolic enzyme activities of nicotinamide quinone oxidoreductase (NQO1, total glutathione transferase (using DCNB and mu-class glutathione transferase (using CDNB were determined in the treated and control animals and compared. Results In prostatic tissues, sulforaphane produced modest but significant increases in the enzymatic activities of NQO1, total GST and GST-mu compared to control animals. β-naphthoflavone significantly increased NQO1 and GST-mu activities and curcumin increased total GST and GST-mu enzymatic activities. Dimethyl fumarate did not significantly increase prostatic phase 2 enzyme activity. Compared to control animals, sulforaphane also significantly induced NQO1 or total GST enzyme activity in the liver, kidney and, most significantly, in the bladder tissues. All compounds were well tolerated over the course of the gavage feedings. Conclusion Orally administered compounds will induce modestly phase 2 enzyme activity in the prostate although the significance of this degree of induction is unknown. The 4 different compounds also altered phase 2 enzyme activity to different degrees in different tissue types. Orally administered sulforaphane potently induces phase 2 enzymes in bladder tissues and should be investigated as a bladder cancer preventive agent.

  19. Electrochemical properties and diffusion of a redox active surfactant incorporated in bicontinuous cubic and lamellar phase

    International Nuclear Information System (INIS)

    The objective of this study was to investigate the electrochemical behaviour of the divalent redox active surfactant, N-cetyl-N'-methylviologen (CMV), in bicontinuous cubic and lamellar phases. The liquid crystalline phases were prepared from the system glycerolmonooleate (GMO)-water (and brine)-cationic surfactant. A comparison of the phase behaviour of GMO with the monovalent cetyltrimethylammonium bromide (CTAB) and the divalent CMV surfactant showed that the surfactants gave about the same effect at the same surface charge density. The electrochemical measurements were made with a mixture of CTAB and CMV as the surfactant. Cyclic voltammetry was used to study the electrochemistry of CMV incorporated in the cubic and lamellar phases that were spread on a gold electrode. The E 0-values in the cubic samples were more negative (-0.55 V versus SCE) than in the lamellar samples (-0.53 V versus SCE). This can be explained by the higher charge density in the lamellar phase. The diffusion coefficients were also measured in the cubic phase. The mass transport is slowed down about fifty times in the cubic phase compared to in the pure electrolyte. The concentration dependence on the diffusion coefficient was also investigated. No electron hopping could be observed, which suggest that diffusional movement of the redox probe is the main source of charge transport. By placing the samples on a conducting glass slide, spectroelectrochemical investigations were performed. In the lamellar phase strong dimerization was detected at high concentration of viologen, but much less in the cubic phase

  20. Phase and gain control policies for robust active vibration control of flexible structures

    OpenAIRE

    Zhang, Kai; Scorletti, Gérard; Ichchou, Mohamed; Mieyeville, F.

    2013-01-01

    The interest of this paper is to develop a general and systematic robust control methodology for active vibration control of flexible structures. For this purpose, first phase and gain control policies are proposed to impose qualitative frequency-dependent requirements on the controller to consider a complete set of control objectives. Then the proposed control methodology is developed by employing phase and gain control policies in the dynamic output feedback H∞ control: according to the set...

  1. Demonstration of a 4-Sensor Folded Sangac Sensor Array with Active Phase Biasing Scheme

    Institute of Scientific and Technical Information of China (English)

    Zhang-Qi Song; Ming-Ye Yang; Xue-Liang Zhang; Yong-Ming Hu

    2008-01-01

    A 4-sensor folded Sagnae sensor array with an active phase biasing scheme is presented. The overlapping of the signal and noise pulse is avoided through a time division multiplexing scheme and the noise pulses is eliminated almost completely. The scheme can address 16 sensors when the repeat frequency of input pulse is at 68.3 kHz. The alternative phase bias technique is demonstrated, which can provide sensors with stable phase bias. The future benefit of this technique is that the 1/f noise in the circuit can be suppressed.

  2. Dissecting eukaryotic cells by coherent phase microscopy: quantitative analysis of quiescent and activated T lymphocytes

    Science.gov (United States)

    Tychinsky, Vladimir P.; Kretushev, Alexander V.; Vyshenskaya, Tatiana V.; Shtil, Alexander A.

    2012-07-01

    We present a concept for quantitative characterization of a functional state of an individual eukaryotic cell based on interference imaging. The informative parameters of the phase images of quiescent and mitogen-activated T lymphocytes included the phase thickness, phase volume, the area, and the size of organelles. These parameters were obtained without a special hypothesis about cell structure. Combinations of these parameters generated a ``phase portrait'' of the cell. A simplified spherical multilayer optic model of a T lymphocyte was used to calculate the refractivity profile, to identify structural elements of the image with the organelles, and to interpret the parameters of the phase portrait. The values of phase image parameters underwent characteristic changes in the course of mitogenic stimulation of T cells; thereby, the functional state of individual cells can be described using these parameters. Because the values of the components of the phase portrait are measured in absolute units, it is possible to compare the parameters of images obtained with different interference microscopes. Thus, the analysis of phase portraits provides a new and perspective approach for quantitative, real-time analysis of subcellular structure and physiologic state of an individual cell.

  3. THREE-PHASE ACTIVE POWER FILTER CONTROLLER FOR BALANCED AND UNBALANCED NON-LINEAR LOAD

    Directory of Open Access Journals (Sweden)

    G.NAGESWARA RAO

    2010-09-01

    Full Text Available The active power filter produces equal but opposite harmonic currents to the point of connection with the nonlinear load. This results in a reduction of the original distortion and correction of the power factor. A threephase insulated gate bipolar transistor based current controlled voltage source inverter with a dc bus capacitor is used as an active filter. The firing pulses to the shunt active filter will be generated by using sine PWM method. The models for three-phase active power filter controller for balanced and unbalanced non-linear load is made and is simulated using Matlab/simulink software.

  4. Dramatic activity of mixed-phase TiO2 photocatalyst synthesized by hydrothermal method

    Science.gov (United States)

    Li, Huiquan; Xu, Bolian; Fan, Yining

    2013-02-01

    The mixed-phase TiO2 photocatalysts with different anatase/rutile/brookite ratios and high specific surface area (157-218 m2/g) were prepared by hydrothermal method at 100 °C and the effect of rutile content in TiO2 on the BET surface area, light absorption and separation efficiency of photogenerated charge carriers was studied and correlated to the photocatalytic activity of TiO2. Rutile content increased from 0% to 100% by increasing the amount of TiCl4 in aqueous phase and the initial pH value of reaction solution played an important role in the phase composition of TiO2. The photocatalytic mechanism of mixed-phase TiO2 was discussed.

  5. Advanced Control Strategy for Single-Phase Voltage-Source Active Rectifier with Low Harmonic Emission

    Science.gov (United States)

    Blahník, Vojtĕch; Peroutka, Zdenĕk; Talla, Jakub

    2014-03-01

    This paper introduces the advanced control of single-phase voltage-source active rectifier. This control provide direct control of trolley-wire current and active damping of low-frequency disturbances at the converter ac side. Our proposed control strategy combines PR controller with feed-forward model and low-frequency harmonic compensator based on resonant controllers. Achieved experimental results show excellent converter behavior, where converter is fed by strongly distorted supply voltage.

  6. Radioiodination of interleukin 2 to high specific activities by the vapor-phase chloramine T method

    International Nuclear Information System (INIS)

    Recombinant human interleukin 2 (IL-2) was radioiodinated utilizing the vapor phase chloramine T method of iodination. The method is rapid, reproducible, and allows the efficient radioiodination of IL-2 to specific activities higher than those previously attained with full retention of biological activity. IL-2 radioiodinated by this method binds with high affinity to receptors present on phytohemagglutinin-stimulated peripheral blood lymphocytes and should be useful for the study of receptor structure and function

  7. Phase I trial with BMS-275183, a novel oral taxane with promising antitumor activity

    NARCIS (Netherlands)

    Broker, LE; de Vos, FYFL; van Groeningen, CJ; Kuenen, BC; Gall, HE; Woo, MH; Voi, M; Gietema, JA; deVries, EGE; Giaccone, G

    2006-01-01

    Purpose: BMS-275183 is an orally administered C-4 methyl carbonate analogue of paclitaxel. We did a dose-escalating phase I study to investigate its safety, tolerability, pharmacokinetics, and possible antitumor activity. Experimental Design: A cycle consisted of four weekly doses of BMS-275183. The

  8. Highly Integrated Application Specific MMICS for Active Phased Array Radar Applications

    NARCIS (Netherlands)

    Bogaart, F.L.M. van den

    2000-01-01

    Application specific MMIC solutions for active array radar, developed at TNO-FEL. are presented. The use and application of these MMICs in their respective radar systems will be shown. These MMICs address the needs for current and future phased-array topologies as for example the concept of "smart s

  9. Purification of Active Myrosinase from Plants by Aqueous Two-Phase Counter-Current Chromatography

    Science.gov (United States)

    Wade, Kristina L.; Ito, Yoichiro; Ramarathnam, Aarthi; Holtzclaw, W. David; Fahey, Jed W.

    2014-01-01

    Introduction Myrosinase (thioglucoside glucohydrolase; E.C. 3.2.1.147), is a plant enzyme of increasing interest and importance to the biomedical community. Myrosinase catalyses the formation of isothiocyanates such as sulforaphane (frombroccoli) and 4-(α-l-rhamnopyranosyloxy)benzyl isothiocyanate (from moringa), which are potent inducers of the cytoprotective phase-2 response in humans, by hydrolysis of their abundant glucosinolate (β-thioglucoside N-hydroxysulphate) precursors. Objective To develop an aqueous two-phase counter-current chromatography (CCC) system for the rapid, three-step purification of catalytically active myrosinase. Methods A high-concentration potassium phosphate and polyethylene glycol biphasic aqueous two-phase system (ATPS) is used with a newly developed CCC configuration that utilises spiral-wound, flat-twisted tubing (with an ovoid cross-section). Results Making the initial crude plant extract directly in the ATPS and injecting only the lower phase permitted highly selective partitioning of the myrosinase complex before a short chromatography on a spiral disk CCC. Optimum phase retention and separation of myrosinase from other plant proteins afforded a 60-fold purification. Conclusion Catalytically active myrosinase is purified from 3-day broccoli sprouts, 7-day daikon sprouts, mustard seeds and the leaves of field-grown moringa trees, in a CCC system that is predictably scalable. PMID:25130502

  10. Dead layer and active volume determination for GERDA Phase II detectors

    Energy Technology Data Exchange (ETDEWEB)

    Lehnert, Bjoern [TU Dresden (Germany); Collaboration: GERDA-Collaboration

    2013-07-01

    The GERDA experiment investigates the neutrinoless double beta decay of {sup 76}Ge and is currently running Phase I of its physics program. Using the same isotope as the Heidelberg Moscow (HDM) experiment, GERDA aims to directly test the claim of observation by a subset of the HDM collaboration. For the update to Phase II of the experiment in 2013, the collaboration organized the production of 30 new Broad Energy Germanium (BEGe) type detectors from original 35 kg enriched material and tested their performance in the low background laboratory HADES in SCK.CEN, Belgium. With additional 20 kg of detectors, GERDA aims to probe the degenerated hierarchy scenario. One of the crucial detector parameters is the active volume (AV) fraction which directly enters into all physics analysis. This talk presents the methodology of dead layer and AV determination with different calibration sources such as {sup 241}Am, {sup 133}Ba, {sup 60}Co and {sup 228}Th and the results obtained for the new Phase II detectors. Furthermore, the AV fraction turned out to be the largest systematic uncertainty in the analysis of Phase I data which makes it imperative to reduce its uncertainty for Phase II. This talk addresses the major contributions to the AV uncertainty and gives an outlook for improvements in Phase II analysis.

  11. Dead layer and active volume determination for GERDA Phase II detectors

    International Nuclear Information System (INIS)

    The GERDA experiment investigates the neutrinoless double beta decay of 76Ge and is currently running Phase I of its physics program. Using the same isotope as the Heidelberg Moscow (HDM) experiment, GERDA aims to directly test the claim of observation by a subset of the HDM collaboration. For the update to Phase II of the experiment in 2013, the collaboration organized the production of 30 new Broad Energy Germanium (BEGe) type detectors from original 35 kg enriched material and tested their performance in the low background laboratory HADES in SCK.CEN, Belgium. With additional 20 kg of detectors, GERDA aims to probe the degenerated hierarchy scenario. One of the crucial detector parameters is the active volume (AV) fraction which directly enters into all physics analysis. This talk presents the methodology of dead layer and AV determination with different calibration sources such as 241Am, 133Ba, 60Co and 228Th and the results obtained for the new Phase II detectors. Furthermore, the AV fraction turned out to be the largest systematic uncertainty in the analysis of Phase I data which makes it imperative to reduce its uncertainty for Phase II. This talk addresses the major contributions to the AV uncertainty and gives an outlook for improvements in Phase II analysis.

  12. Liver protein kinase A activity is decreased during the late hypoglycemic phase of sepsis.

    Science.gov (United States)

    Hsu, C; Hsu, H K; Yang, S L; Jao, H C; Liu, M S

    1999-10-01

    Changes in protein kinase A (PKA, or cAMP-dependent protein kinase) activity in the rat liver during different metabolic phases of sepsis were investigated. Sepsis was induced by cecal ligation and puncture (CLP). Experiments were divided into 3 groups: control, early sepsis, and late sepsis. Early and late sepsis refer to those animals killed at 9 and 18 h, respectively, after CLP. Hepatic PKA was extracted and partially purified by acid precipitation, ammonium sulfate fractionation, and diethylaminoethyl (DEAE)-cellulose chromatography. PKA was eluted from DEAE-cellulose column with a linear NaCl gradient. Two peaks of PKA, type I (eluted at low ionic strength) and type II (eluted at high ionic strength), were collected and their activities were determined on the basis of the rate of incorporation of [gamma-32-P]ATP into histone. The results show that during early sepsis, both type I and type II PKA activities remained unchanged. During late sepsis, type I PKA activity was decreased by 40.7-53.6%, whereas type II PKA activity was unaffected. Kinetic analysis of the data on type I PKA during the late phase of sepsis reveals that the Vmax (maximal velocity) values for ATP, cAMP, and histone were decreased by 40.7, 53.6, and 47.3%, respectively whereas the Km (substrate concentration required for half-maximal enzymatic activity) values for ATP, cAMP, and histone were unaltered. These data indicate that type I PKA was inactivated during the late hypoglycemic phase of sepsis in the rat liver. Because PKA-mediated phosphorylation plays an important role in the regulation of hepatic glucose metabolism, an inactivation of PKA may contribute to the development of hypoglycemia during the late phase of sepsis. PMID:10509629

  13. Phase topology of a NR/BR elastomer blend with active filler

    OpenAIRE

    Plavšić Milenko B.; Pajić-Lijaković Ivana; Čubrić Branislav; Popović Radivoj S.; Bugarski Branko M.; Popović Ružica G.; Lazić Nada L.

    2003-01-01

    The relations between the structure and mechanical properties of a polymer blend of natural (NR) and polybutadiene (BR) rubber (i.e. a NR/BR blend with the weight ratio of the components 70/30) filled with active carbon black were analysed. The properties of the individual phases in the blend were resolved by modeling the stress-strain relationship according to the Bauer procedure for high extensions. The obtained results indicated that BR is the dispersed phase, having a higher modulus, whic...

  14. X-ray activity phased with planet motion in HD 189733?

    OpenAIRE

    Pillitteri, I.; Guenther, H. M.; Wolk, S. J.; Kashyap, V.; Cohen, O.

    2011-01-01

    We report on the follow-up XMM-Newton observation of the planet-hosting star HD 189733 we obtained in April 2011. We observe a flare just after the secondary transit of the hot Jupiter. This event shares the same phase and many of the characteristics of the flare we observed in 2009. We suggest that a systematic interaction between planet and stellar magnetic fields when the planet passes close to active regions on the star can lead to periodic variability phased with planetary motion. By mea...

  15. Effects of 5-Aza-Cde on DNA Methylation and Expression of hMLHl and MGMT Gene in Lung Cancer Cell Line A549/DDP%5-氮杂-2′脱氧胞苷对肺癌 A549/DDP 细胞hMLHl,MGMT 基因甲基化及其表达的影响

    Institute of Scientific and Technical Information of China (English)

    王虹; 李丽丽; 张吉才; 高波; 骆海军

    2015-01-01

    Objective To investigate the effects of 5-Aza-2′-deoxycytidine (5-Aza-Cde)on DNA methylation and expression of hMLH1 and MGMT gene in the human lung cancer cell line A549/DDP.Methods A549/DDP cells were cultured with RPMI 1 640 medium and were treated with 5 μmol/L DNA methyhransferase inhibitor 5-Aza-Cde.Methylation-specific pol-ymerase chain reaetioll (MSP)was used to detect the promoter methylation state of the hMLH1 and MGMT gene.RT-PCR was used to detect the mRNA expression of hMLH1 and MGMT before and after treatment with 5-Aza-Cde,respectively. Results Before treatment with 5-Aza-Cde,hMLH1 and MGMT expressions were absent,and promoter hypermethylation of the hMLH1 and MGMT gene were detected in A549 cells.After treatment with 5-Aza-Cde,the promoter region of the hM-LH1 and MGMT gene exhibited a demethylation state,and their mRNA expressions were increased.Conclusion Promoter hypermethyhtion is amajor mechanism of hMLH1 and MGMT gene silencing in human lung cancer cells,and can be reversed by the demethylating agent 5-Aza-Cde,which can regulate the expressions of the hMLH1 and MGMT gene.%目的:观察5-氮杂-2′脱氧胞苷(5-Aza-Cde)对体外培养的顺铂(DDP)耐药株肺癌 A549/DDP 细胞 hMLH1,MG-MT 基因启动子区 DNA 甲基化状态及其表达的影响,探讨肺癌细胞 hMLH1和 MGMT 基因失活的机制及去甲基化制剂对 hMLH1和 MGMT 基因表达的调控。方法5-Aza-Cde 处理体外1640培养的肺癌 A549/DDP 细胞,甲基化特异性PCR(MSP)法检测用药前后细胞 hMLH1和 MGMT 基因的甲基化状态,RT-PCR 法检测用药前后细胞 hMLH1和 MG-MT mRNA 的表达。结果在对照组 A549细胞当中 hMLH1基因是非甲基化状态和高表达,而 MGMT 显示为低甲基化(部分甲基化)状态和高表达;而在顺铂耐药株 A549-DDP 中,hMLH1和 MGMT 基因均显示高甲基化状态,mRNA 表达下调。结论hMLH1和 MGMT 基因甲基化修饰程度与 mRNA 的表

  16. Waste activated sludge treatment based on temperature staged and biologically phased anaerobic digestion system.

    Science.gov (United States)

    Yu, Jingwen; Zheng, Mingxia; Tao, Tao; Zuo, Jiane; Wang, Kaijun

    2013-10-01

    The concept of temperature staged and biological phased (TSBP) was proposed to enhance the performance of waste-activated sludge anaerobic digestion. Semi-continuous experiments were used to investigate the effect of temperature (35 to 70 degrees C) as well as the hydraulic retention time (HRT) (2, 4 and 6 days) on the acidogenic phase. The results showed that the solubilization degree of waste-activated sludge increased from 14.7% to 30.1% with temperature increasing from 35 to 70 degrees C, while the acidification degree was highest at 45 degrees C (17.6%), and this was quite different from the temperature impact on hydrolysis. Compared with HRT of 2 and 6 days, 4 days was chosen as the appropriate HRT because of its relatively high solubilization degree (24.6%) and acidification degree (20.1%) at 45 degrees C. The TSBP system combined the acidogenic reactor (45 degrees C, 4 days) with the methanogenic reactor (35 degrees C, 16 days) and the results showed 84.8% and 11.4% higher methane yield and volatile solid reduction, respectively, compared with that of the single-stage anaerobic digestion system with HRT of 20 days at 35 degrees C. Moreover, different microbial morphologies were observed in the acidogenic- and methanogenic-phase reactors, which resulted from the temperature control and HRT adjustment. All the above results indicated that 45 degrees C was the optimum temperature to inhibit the activity of methanogenic bacteria in the acidogenic phase, and temperature staging and phase separation was thus accomplished. The advantages of the TSBP process were also confirmed by a full-scale waste-activated sludge anaerobic digestion project which was an energy self-sufficient system.

  17. Hemispheric activation during planning and execution phases in reaching post stroke: a consort study.

    Science.gov (United States)

    Fang, Yin; Daly, Janis J; Hansley, Jeff; Yao, Wan X; Yang, Qi; Sun, Jiayang; Hvorat, Ken; Pundik, Svetlana; Yue, Guang H

    2015-01-01

    Enhanced activation in the non-lesion hemisphere in stroke patients was widely observed during movement of the affected upper limb, but its functional role related to motor planning and execution is still unknown.This study was to characterize the activation in the non-lesion hemisphere during movement planning and execution by localizing sources of high-density electroencephalography (EEG) signal and estimating the source strength (current density [A/m]).Ten individuals with chronic stroke and shoulder/elbow coordination deficits and 5 healthy controls participated in the study.EEG (64 channels) was recorded from scalp electrodes while the subjects performed a reach task involving shoulder flexion and elbow extension of the affected (patients) or dominant (controls) upper extremity. Sources of the EEG were obtained and analyzed at 17 time points across movement preparation and execution phases. A 3-layer boundary element model was overlaid and used to identify the brain activation sources. A distributed current density model, low-resolution electromagnetic tomography (LORETA) L1 norm method, was applied to the data pre-processed by independent component analysis.Subjects with stroke had stronger source strength in the sensorimotor cortices during the movement compared with the controls. Their contralesional/lesional activation ratio (CTLR) for the primary motor cortices was significantly higher than that of the controls during the movement-planning phase, but not during the execution phase. The CTLR was higher in planning than in the execution phase in the stroke group.Excessive contralesional motor cortical activation appears to be more related to movement preparation rather than execution in chronic stroke.

  18. Protein kinase a activity is increased in rat heart during late hypodynamic phase of sepsis.

    Science.gov (United States)

    Yang, S L; Hsu, C; Lue, S I; Hsu, H K; Liu, M S

    1997-07-01

    Changes in the activities of protein kinase A (PKA, or cAMP-dependent protein kinase) in rat heart during different cardiodynamic phases of sepsis were investigated. Sepsis was induced by cecal ligation and puncture. Experiments were divided into three groups: control, early sepsis, and late sepsis. Early and late sepsis refers to those animals killed at 9 and 18 h, respectively, after cecal ligation and puncture. Cardiac PKA was extracted and partially purified by acid precipitation, ammonium sulfate fractionation, and DEAE-cellulose chromatography. PKA was eluted from DEAE-cellulose column with a linear NaCl gradient. Two peaks of PKA, type I (eluted at low ionic strength) and type II (eluted at high ionic strength), were collected and their activities were determined based on the rate of incorporation of [gamma-32P]ATP into histone. Results obtained show that during early sepsis, both type I and type II PKA activities were unaffected. During late sepsis, type I PKA activities were stimulated by 66.7-97.7%, while type II PKA activities remained constant. Kinetic analysis of the data on type I PKA during late sepsis reveals that the Vmax values for ATP, cAMP, and histone were increased by 84.7, 66.7, and 97.7%, respectively; while the Km values for ATP, cAMP, and histone were unaltered. These data indicate that type I PKA is activated in rat heart during late hypodynamic phase of sepsis. Since kinase-mediated phosphorylation plays an important role in regulating myocardial function and metabolism, an activation of type I PKA during late sepsis may contribute to the development of altered myocardial function during hypodynamic phase of sepsis. PMID:9249915

  19. Liquid-phase adsorption of phenol onto activated carbons prepared with different activation levels

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, C.T.; Teng, H.S.

    2000-07-01

    The paper investigates the influence of the pore size distribution of activated carbon on the adsorption of phenol from aqueous solutions. Activated carbons with different porous structures were prepared by gasifying a bituminous coal char to different extents of burn-off. The results of adsorption experiments show that the phenol capacity of these carbons does not proportionally increase with their BET surface area. This reflects the heterogeneity of the carbon surface for adsorption. The pore size distributions of these carbons were found to vary with the burn-off level. The paper demonstrates that the heterogeneity of carbon surface for the phenol adsorption can be attributed to the different energies required for adsorption in different-size micropores.

  20. Fe-rich border and activation energy of phase decomposition in a Fe–Cr alloy

    Energy Technology Data Exchange (ETDEWEB)

    Dubiel, S.M., E-mail: Stanislaw.Dubiel@fis.agh.edu.pl; Żukrowski, J.

    2013-08-15

    Concentration of Cr in the Fe-rich α-phase, x, resulted from a phase decomposition caused by an isothermal annealing at T = 415 and 450 °C of a non-irradiated (NR) Fe–Cr14 EFDA sample and that of a He-ions irradiated one (IR) annealed at 415 °C was determined with Mossbauer spectroscopy. The x-value in the latter was by ∼3 at% higher than the one in the NR-counterpart. The activation energy for the phase decomposition in the NR-sample was 122 kJ mol{sup −1}. In the IR-sample its value was by 12 kJ mol{sup −1} lower. Avrami exponents for the NR-samples were close to 0.5, and that the IR-sample had a value of about 1. - Highlights: • Fe-rich border of miscibility gap in Fe–Cr alloys at 415 and 450 °C was determined. • In the He-ion irradiated alloy the miscibility gap at 415 °C was narrower by 3 at%. • Activation energy for the phase separation in non-irradiated samples was 122 kJ mol{sup −1}. • Avrami exponent was 0.5 and 1.0 for non-irradiated and irradiated samples, respectively.

  1. Coronal Dynamic Activities in the Declining Phase of a Solar Cycle

    CERN Document Server

    Jang, Minhwan; Hong, Sunhak; Choe, G S

    2016-01-01

    It has been known that some solar activity indicators show a double-peak feature in their evolution through a solar cycle, which is not conspicuous in sunspot number. In this letter, we investigate the high solar dynamic activity in the declining phase of the sunspot cycle by examining the evolution of polar and low latitude coronal hole areas and the statistics of splitting and merging events of coronal holes and coronal mass ejections detected by SOHO/LASCO C3 in solar cycle 23. Although the total coronal hole area is at its maximum near the sunspot minimum, in which polar coronal holes prevail, it shows a comparable second maximum in the declining phase of the cycle, in which low latitude coronal holes are dominant. The events of coronal hole splitting or merging, which are attributed to surface motions of magnetic fluxes, are also mostly populated in the declining phase of the cycle. The far-reaching C3 coronal mass ejections are also over-populated in the declining phase of the cycle. From these results ...

  2. Genetic Algorithm-Based Design of the Active Damping for an LCL-Filter Three-Phase Active Rectifier

    DEFF Research Database (Denmark)

    Liserre, Marco; Aquila, Antonio Dell; Blaabjerg, Frede

    2004-01-01

    by a three-phase active rectifier. However, stability problems can arise in the current control loop. In order to overcome them, a damping resistor can be inserted, at the price of a reduction of efficiency. The use of active damping by means of control may seem attractive, but it is often limited by the use......Active rectifiers/inverters are becoming used more and more often in regenerative systems and distributed power systems. Typically, the interface between the grid and rectifier is either an inductor or an LCL-filter. The use of an LCL-filter mitigates the switching ripple injected in the grid...... or complex calculations. Moreover, in the paper particular attention is devoted to the susceptibility of the systems in a high polluting environment....

  3. High photocatalytic activity of mixed anatase-rutile phases on commercial TiO2 nanoparticles

    Science.gov (United States)

    Ruu Siah, Wai; Lintang, Hendrik O.; Shamsuddin, Mustaffa; Yuliati, Leny

    2016-02-01

    Titanium dioxide (TiO2) is well-known as an active photocatalyst for degradation of various organic pollutants. Over the years, a wide range of TiO2 nanoparticles with different phase compositions, crystallinities, and surface areas have been developed. Due to the different methods and conditions used to synthesize these commercial TiO2 nanoparticles, the properties and photocatalytic performance would also be different from each other. In this study, the photocatalytic removal of 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4,5- trichlorophenoxyacetic acid (2,4,5-T) was investigated on commercial Evonik P25, Evonik P90, Hombikat UV100 and Hombikat N100 TiO2 nanoparticles. Upon photocatalytic tests, it was found that overall, the photocatalytic activities of the P25 and the P90 were higher than the N100 and the UV100 for the removal of both 2,4-D and 2,4,5-T. The high activities of the P25 and the P90 could be attributed to their phase compositions, which are made up of a mixture of anatase and rutile phases of TiO2. Whereas, the UV100 and the N100 are made up of 100% anatase phase of TiO2. The synergistic effect of the anatase/rutile mixture was reported to slow down the recombination rate of photogenerated electron-hole pairs. Consequently, the photocatalytic activity was increased on these TiO2 nanoparticles.

  4. Carrier phase shifted SPWM based on current sourced multi-modular converter for active power filter

    Institute of Scientific and Technical Information of China (English)

    王立乔; 李建林; 张仲超

    2004-01-01

    A novel current-source active power filter(APF)based on multi-modular converter with carrier phase-shifted SPWM(CPS-SPWM)technique is proposed.With this technique,the effect of equivalent high switching frequency converter is obtained with low switching frequency converter.It is very promising in current-source APF that adopt superconducting magnetic energy storage component.

  5. PI, FUZZY and ANFIS Control of 3-Phase Shunt Active Power Filter

    Directory of Open Access Journals (Sweden)

    Brahmaiah.routhu

    2013-06-01

    Full Text Available this paper describes control of 3-phase shunt active filter by using PI, fuzzy and ANFIS controls to improve the power quality and reactive power compensation and harmonic current compensation due to nonlinear loads. The controller is capable of controlling the DC capacitor voltage capable of reference source current. Hysteresis control is used to control the current in PWM inverter. The simulation results reveals that comparative study of all this results shows the advantage anddisadvantages of 3 control strategies.

  6. Phase Locking Phenomena and Electroencephalogram-Like Activities in Dynamic Neuronal Systems

    Institute of Scientific and Technical Information of China (English)

    XU Xin-Jian; WANG Sheng-Jun; TANG Wei; WANG Ying-Hai

    2005-01-01

    @@ We study signal detection and transduction of dynamic neuronal systems under the influence of external noise,white and coloured. Based on simulations, we show explicitly phase locking phenomena between the output and the input of a single neuron and Electroencephalogram-like activities on neural networks with small-world connectivity. The numerical results prove that the dynamic neuronal system can be adjusted to an optimal sensitive state for signal processing in the presence of additive noise.

  7. Oscillatory phase modulates the timing of neuronal activations and resulting behavior.

    Science.gov (United States)

    Coon, W G; Gunduz, A; Brunner, P; Ritaccio, A L; Pesaran, B; Schalk, G

    2016-06-01

    Human behavioral response timing is highly variable from trial to trial. While it is generally understood that behavioral variability must be due to trial-by-trial variations in brain function, it is still largely unknown which physiological mechanisms govern the timing of neural activity as it travels through networks of neuronal populations, and how variations in the timing of neural activity relate to variations in the timing of behavior. In our study, we submitted recordings from the cortical surface to novel analytic techniques to chart the trajectory of neuronal population activity across the human cortex in single trials, and found joint modulation of the timing of this activity and of consequent behavior by neuronal oscillations in the alpha band (8-12Hz). Specifically, we established that the onset of population activity tends to occur during the trough of oscillatory activity, and that deviations from this preferred relationship are related to changes in the timing of population activity and the speed of the resulting behavioral response. These results indicate that neuronal activity incurs variable delays as it propagates across neuronal populations, and that the duration of each delay is a function of the instantaneous phase of oscillatory activity. We conclude that the results presented in this paper are supportive of a general model for variability in the effective speed of information transmission in the human brain and for variability in the timing of human behavior. PMID:26975551

  8. CO oxidation over ruthenium: identification of the catalytically active phases at near-atmospheric pressures

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Feng; Goodman, Wayne D.

    2012-05-21

    CO oxidation was carried out over Ru(0001) and RuO2(110) thin film grown on Ru(0001) at various O2/CO ratios near atmospheric pressures. Reaction kinetics, coupled with in situ polarization modulation infrared reflection absorption spectroscopy (PM-IRAS) and post-reaction Auger electron spectroscopy (AES) measurements were used to identify the catalytically relevant phases at different reaction conditions. Under stoichiometric and reducing conditions at all reaction temperatures, as well as net-oxidizing reaction conditions below {approx}475 K, a reduced metallic phase with chemisorbed oxygen is the thermodynamically stable and catalytically active phase. On this surface CO oxidation occurs at surface defect sites, for example step edges. Only at net-oxidizing reaction conditions and above {approx}475 K is the RuO2 thin film grown on metallic Ru stable and active. However, RuO2 is not active itself without the existence of the metal substrate, suggesting the importance of a strong metal-substrate interaction (SMSI).

  9. Active phases and flickering of a symbiotic recurrent nova T CrB

    CERN Document Server

    Ilkiewicz, Krystian; Stoyanov, Kiril; Manousakis, Antonios; Miszalski, Brent

    2016-01-01

    T CrB is a symbiotic recurrent nova known to exhibit active phases, characterised by apparent increases in the hot component temperature and the appearance of flickering, i.e. changes in the observed flux on the time-scale of minutes. Historical UV observations have ruled out orbital variability as an explanation for flickering and instead suggest flickering is caused by variable mass transfer. We have analysed optical and X-ray observations to investigate the nature of the flickering as well as the active phases in T CrB. The spectroscopic and photometric observations confirm that the active phases follow two periods of ~1000d and ~5000d. Flickering in the X-rays is detected and follows an amplitude-flux relationship similar to that observed in the optical. The flickering is most prominent at harder X-ray energies, suggesting that it originates in the boundary layer between the accretion disc and the white dwarf. The X-ray radiation from the boundary layer is then reprocessed by a thick accretion disc or a n...

  10. Waves of Cdk1 Activity in S Phase Synchronize the Cell Cycle in Drosophila Embryos.

    Science.gov (United States)

    Deneke, Victoria E; Melbinger, Anna; Vergassola, Massimo; Di Talia, Stefano

    2016-08-22

    Embryos of most metazoans undergo rapid and synchronous cell cycles following fertilization. While diffusion is too slow for synchronization of mitosis across large spatial scales, waves of Cdk1 activity represent a possible process of synchronization. However, the mechanisms regulating Cdk1 waves during embryonic development remain poorly understood. Using biosensors of Cdk1 and Chk1 activities, we dissect the regulation of Cdk1 waves in the Drosophila syncytial blastoderm. We show that Cdk1 waves are not controlled by the mitotic switch but by a double-negative feedback between Cdk1 and Chk1. Using mathematical modeling and surgical ligations, we demonstrate a fundamental distinction between S phase Cdk1 waves, which propagate as active trigger waves in an excitable medium, and mitotic Cdk1 waves, which propagate as passive phase waves. Our findings show that in Drosophila embryos, Cdk1 positive feedback serves primarily to ensure the rapid onset of mitosis, while wave propagation is regulated by S phase events. PMID:27554859

  11. Activation energies for gas-phase dissociations of multiply charged ions from electrospay ionization mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Busman, M.; Rockwood, A.L.; Smith, R.D. [Pacific Northwest Lab., Richland, WA (United States)

    1992-03-19

    The reactions of multiply protonated melittin molecular ions of various charge states produced from an electrospray ionization source have been studied. The flow of ions entrained in gas through a heated metal capillary inlet serves as a reaction vessel for gas-phase measurements of molecular ion reaction rates using mass spectrometry. Activation energies for the unimolecular dissociation reactions are calculated from the temperature dependence of the reaction kinetics. The differences in activation energies for the reactions of the different charge states are attributed to the destabilizing effect of Coulombic repulsion for high charged ions. 18 refs., 3 figs., 1 tab.

  12. DC-bias Cancellation for Phase Shift Controlled Dual Active Bridge

    DEFF Research Database (Denmark)

    Alzola, Rafael Pena; Mathe, Laszlo; Liserre, Marco;

    2013-01-01

    The dual active bridge topology allows bidirectional power flow and galvanic isolation for DC/DC energy conversion. These features have made it the possible backbone of the future smart transformer for distribution. The different voltage drops and commutation dead-times of the semiconductor...... can damage the converter. A typical approach to avoid the DC-bias is placing a capacitor in series with the transformer. This capacitor suffers large current variations, reducing its reliability, and complicates the control. The dual active bridge usually handles the power flow by modifying the phase...

  13. Single-phase shunt active filter interfacing renewable energy sources with the power grid

    OpenAIRE

    Neves, Pedro; Gonçalves, Domingos; Pinto, J. G.; Alves, Renato; Afonso, João L.

    2009-01-01

    This paper presents a single-phase Shunt Active Filter combined with a Maximum Power Point Tracker (MPPT) connected to a solar panel array. The Shunt Active Filter’s power stage consists of a two-leg IGBT inverter commanded by a Digital Signal Processor (DSP) with control based on the Theory of Instantaneous Reactive Power (p-q Theory). The MPPT is based on a step-up circuit commanded by a DSP with MPPT Algorithm implemented. The output of the MPPT circuit is connected...

  14. VARIETAL DEPENDENCE OF ANTIOXIDANT ACTIVITY IN DIFFERENT ANATOMICAL PARTS OF COMMON BUCKWHEAT (FAGOPYRUM ESCULENTUM MOENCH IN DIFFERENT GROWTH PHASES

    Directory of Open Access Journals (Sweden)

    Iveta Čičová

    2012-02-01

    Full Text Available The pseudocereals such as buckwheat, quinoa, amaranth have attracted interest in recent years. One of the reasons for this renewed interest is their excellent nutrient profile. In addition to being one of the important energy sources due to their starch content, these pseudocereals provide good quality protein, dietary fibre and lipids rich in unsaturated fats. The aim of our work was to study antioxidant activity in 4 chosen cultivars of common buckwheat during vegetation period. Four cultivars were analysed: Špačinska, Bambi, Jana C1, Aiva. Samples of plant material were obtained from Plant Producion Research Centre in Piešťany. Antioxidant activity (AOA of stem, leaves, flowers and seeds of buckwheat was assessed with using of DPPH radical (2.2 – diphenyl-1-picrylhydrazyl at wavelength 515.6 nm. The antioxidant activity of buckwheat was evaluated in growth phases I. (formations of buds, in phase II. (at the beginning of flowering, in phase III. (full flowering, in phase IV. (full ripeness. The antioxidant activity in stems of all tested cultivars of common buckwheat was in range from 49.109 % (Špačinska, phase I. to 73.705 % (Špačinska, phase IV.. The antioxidant activity in leaves of all tested varieties of common buckwheat was in range from 77.937 % (Bambi, phase IV. to 99.655 % (Bambi, phase II.. The antioxidant activity in flowers of all tested varieties of common buckwheat was in range from 88.75 % (Bambi, phase III. to 92.665 % (Špačinska, phase I.. The antioxidant activity in seeds of all tested cultivars of common buckwheat was in range from 39.787 % (Špačinska, phase III. to 88.241 % (Bambi, phase III.. From the standpoint of antioxidant activity in individual plant parts the cultivars Špačinska, Bambi were the most suitable ones for food productions.

  15. Aqueous phase adsorption of different sized molecules on activated carbon fibers: Effect of textural properties.

    Science.gov (United States)

    Prajapati, Yogendra N; Bhaduri, Bhaskar; Joshi, Harish C; Srivastava, Anurag; Verma, Nishith

    2016-07-01

    The effect that the textural properties of rayon-based activated carbon fibers (ACFs), such as the BET surface area and pore size distribution (PSD), have on the adsorption of differently sized molecules, namely, brilliant yellow (BY), methyl orange (MO) and phenol (PH), was investigated in the aqueous phase. ACF samples with different BET areas and PSDs were produced by steam-activating carbonized fibers for different activation times (0.25, 0.5, and 1 h). The samples activated for 0.25 h were predominantly microporous, whereas those activated for relatively longer times contained hierarchical micro-mesopores. The adsorption capacities of the ACFs for the adsorbate increased with increasing BET surface area and pore volume, and ranged from 51 to 1306 mg/g depending on the textural properties of the ACFs and adsorbate size. The adsorption capacities of the hierarchical ACF samples followed the order BY > MO > PH. Interestingly, the number of molecules adsorbed by the ACFs followed the reverse order: PH > MO > BY. This anomaly was attributed to the increasing molecular weight of the PH, MO and BY molecules. The equilibrium adsorption data were described using the Langmuir isotherm. This study shows that suitable textural modifications to ACFs are required for the efficient aqueous phase removal of an adsorbate. PMID:27107386

  16. The effect of phase partitioning of semivolatile compounds on the measured CCN activity of aerosol particles

    Directory of Open Access Journals (Sweden)

    S. Romakkaniemi

    2013-09-01

    Full Text Available The effect of inorganic semivolatile aerosol compounds on the CCN activity of aerosol particles was studied by using a computational model for a DMT-CCN counter, a cloud parcel model for condensation kinetics and experiments to quantify the modelled results. Concentrations of water vapour and semivolatiles as well as aerosol trajectories in the CCN column were calculated by a computational fluid dynamics model. These trajectories and vapour concentrations were then used as an input for the cloud parcel model to simulate mass transfer kinetics of water and semivolatiles between aerosol particles and the gas phase. Two different questions were studied: (1 how big fraction of semivolatiles is evaporated from particles before activation in the CCN counter? (2 How much the CCN activity can be increased due to condensation of semivolatiles prior to the maximum water supersaturation in the case of high semivolatile concentration in the gas phase? The results show that, to increase the CCN activity of aerosol particles, a very high gas phase concentration (as compared to typical ambient conditions is needed. We used nitric acid as a test compound. A concentration of several ppb or higher is needed for measurable effect. In the case of particle evaporation, we used ammonium nitrate as a test compound and found that it partially evaporates before maximum supersaturation is reached in the CCN counter, thus causing an underestimation of CCN activity. The effect of evaporation is clearly visible in all supersaturations, leading to an underestimation of the critical dry diameter by 10 to 15 nanometres in the case of ammonium nitrate particles in different supersaturations. This result was also confirmed by measurements in supersaturations between 0.1 and 0.7%.

  17. The effect of phase partitioning of semivolatile compounds on the measured CCN activity of aerosol particles

    Science.gov (United States)

    Romakkaniemi, S.; Jaatinen, A.; Laaksonen, A.; Nenes, A.; Raatikainen, T.

    2013-09-01

    The effect of inorganic semivolatile aerosol compounds on the CCN activity of aerosol particles was studied by using a computational model for a DMT-CCN counter, a cloud parcel model for condensation kinetics and experiments to quantify the modelled results. Concentrations of water vapour and semivolatiles as well as aerosol trajectories in the CCN column were calculated by a computational fluid dynamics model. These trajectories and vapour concentrations were then used as an input for the cloud parcel model to simulate mass transfer kinetics of water and semivolatiles between aerosol particles and the gas phase. Two different questions were studied: (1) how big fraction of semivolatiles is evaporated from particles before activation in the CCN counter? (2) How much the CCN activity can be increased due to condensation of semivolatiles prior to the maximum water supersaturation in the case of high semivolatile concentration in the gas phase? The results show that, to increase the CCN activity of aerosol particles, a very high gas phase concentration (as compared to typical ambient conditions) is needed. We used nitric acid as a test compound. A concentration of several ppb or higher is needed for measurable effect. In the case of particle evaporation, we used ammonium nitrate as a test compound and found that it partially evaporates before maximum supersaturation is reached in the CCN counter, thus causing an underestimation of CCN activity. The effect of evaporation is clearly visible in all supersaturations, leading to an underestimation of the critical dry diameter by 10 to 15 nanometres in the case of ammonium nitrate particles in different supersaturations. This result was also confirmed by measurements in supersaturations between 0.1 and 0.7%.

  18. In vitro activity of Aloe vera inner gel against microorganisms grown in planktonic and sessile phases.

    Science.gov (United States)

    Cataldi, V; Di Bartolomeo, S; Di Campli, E; Nostro, A; Cellini, L; Di Giulio, M

    2015-12-01

    The failure of traditional antimicrobial treatments is becoming a worldwide problem. The use of Aloe vera is of particular interest for its role as curative agent and its efficacy in complementary therapies for a variety of illnesses. This study evaluated the antimicrobial activity of A. vera inner gel against a panel of microorganisms, Gram-positive and -negative bacteria, and Candida albicans. In addition to A. vera inner gel being used in the treatment of peptic ulcers, in dermatological treatments, and wound healing, it was also tested on the sessile phase of clinical Helicobacter pylori strains (including multi-drug-resistant strains) and on planktonic and sessile phase of Staphylococcus aureus/Pseudomonas aeruginosa clinical isolates from venous leg ulcers.A. vera inner gel expresses its prevalent activity against Gram-negative bacteria and C. albicans in respect to Gram-positive bacteria. The results of the A. vera antibiofilm activity showed a decrease of the produced biomass in a concentration-dependent-way, in each analyzed microorganism. The data obtained show that A. vera inner gel has both an antimicrobial and antibiofilm activity suggesting its potential use for the treatment of microbial infections, in particular for H. pylori gastric infection, especially in case of multi-drug-resistance, as well as for an effective wound dressing.

  19. In vitro activity of Aloe vera inner gel against microorganisms grown in planktonic and sessile phases.

    Science.gov (United States)

    Cataldi, V; Di Bartolomeo, S; Di Campli, E; Nostro, A; Cellini, L; Di Giulio, M

    2015-12-01

    The failure of traditional antimicrobial treatments is becoming a worldwide problem. The use of Aloe vera is of particular interest for its role as curative agent and its efficacy in complementary therapies for a variety of illnesses. This study evaluated the antimicrobial activity of A. vera inner gel against a panel of microorganisms, Gram-positive and -negative bacteria, and Candida albicans. In addition to A. vera inner gel being used in the treatment of peptic ulcers, in dermatological treatments, and wound healing, it was also tested on the sessile phase of clinical Helicobacter pylori strains (including multi-drug-resistant strains) and on planktonic and sessile phase of Staphylococcus aureus/Pseudomonas aeruginosa clinical isolates from venous leg ulcers.A. vera inner gel expresses its prevalent activity against Gram-negative bacteria and C. albicans in respect to Gram-positive bacteria. The results of the A. vera antibiofilm activity showed a decrease of the produced biomass in a concentration-dependent-way, in each analyzed microorganism. The data obtained show that A. vera inner gel has both an antimicrobial and antibiofilm activity suggesting its potential use for the treatment of microbial infections, in particular for H. pylori gastric infection, especially in case of multi-drug-resistance, as well as for an effective wound dressing. PMID:26526205

  20. Switchable Ultrathin Quarter-wave Plate in Terahertz Using Active Phase-change Metasurface.

    Science.gov (United States)

    Wang, Dacheng; Zhang, Lingchao; Gu, Yinghong; Mehmood, M Q; Gong, Yandong; Srivastava, Amar; Jian, Linke; Venkatesan, T; Qiu, Cheng-Wei; Hong, Minghui

    2015-01-01

    Metamaterials open up various exotic means to control electromagnetic waves and among them polarization manipulations with metamaterials have attracted intense attention. As of today, static responses of resonators in metamaterials lead to a narrow-band and single-function operation. Extension of the working frequency relies on multilayer metamaterials or different unit cells, which hinder the development of ultra-compact optical systems. In this work, we demonstrate a switchable ultrathin terahertz quarter-wave plate by hybridizing a phase change material, vanadium dioxide (VO2), with a metasurface. Before the phase transition, VO2 behaves as a semiconductor and the metasurface operates as a quarter-wave plate at 0.468 THz. After the transition to metal phase, the quarter-wave plate operates at 0.502 THz. At the corresponding operating frequencies, the metasurface converts a linearly polarized light into a circularly polarized light. This work reveals the feasibility to realize tunable/active and extremely low-profile polarization manipulation devices in the terahertz regime through the incorporation of such phase-change metasurfaces, enabling novel applications of ultrathin terahertz meta-devices. PMID:26442614

  1. PDF neuron firing phase-shifts key circadian activity neurons in Drosophila.

    Science.gov (United States)

    Guo, Fang; Cerullo, Isadora; Chen, Xiao; Rosbash, Michael

    2014-06-17

    Our experiments address two long-standing models for the function of the Drosophila brain circadian network: a dual oscillator model, which emphasizes the primacy of PDF-containing neurons, and a cell-autonomous model for circadian phase adjustment. We identify five different circadian (E) neurons that are a major source of rhythmicity and locomotor activity. Brief firing of PDF cells at different times of day generates a phase response curve (PRC), which mimics a light-mediated PRC and requires PDF receptor expression in the five E neurons. Firing also resembles light by causing TIM degradation in downstream neurons. Unlike light however, firing-mediated phase-shifting is CRY-independent and exploits the E3 ligase component CUL-3 in the early night to degrade TIM. Our results suggest that PDF neurons integrate light information and then modulate the phase of E cell oscillations and behavioral rhythms. The results also explain how fly brain rhythms persist in constant darkness and without CRY.

  2. Differential activation of intra-S-phase checkpoint in response to tripchlorolide and its effects on DNA replication

    Institute of Scientific and Technical Information of China (English)

    Yan REN; Jia Rui WU

    2004-01-01

    DNA replication is tightly regulated during the S phase of the cell cycle, and the activation of the intra-S-phase checkpoint due to DNA damage usually results in arrest of DNA synthesis. However, the molecular details about the correlation between the checkpoint and regulation of DNA replication are still unclear. To investigate the connections between DNA replication and DNA damage checkpoint, a DNA-damage reagent, tripchlorolide, was applied to CHO (Chinese ovary hamster) cells at early- or middle-stages of the S phase. The early-S-phase treatment with TC significantly delayed the progression of the S phase and caused the phosphorylation of the Chk1 checkpoint protein, whereas the middle-S-phase treatment only slightly slowed down the progression of the S phase. Furthermore, the analysis of DNA replication patterns revealed that replication pattern Ⅱ was greatly prolonged in the cells treated with the drug during the early-S phase, whereas the late-replication patterns of these cells were hardly detected, suggesting that the activation of the intra-S-phase checkpoint inhibits the late-origin firing of DNA replication. We conclude that cells at different stages of the S phase are differentially sensitive to the DNA-damage reagent, and the activation of the intra-Sphase checkpoint blocks the DNA replication progression in the late stage of S phase.

  3. Wireless Power Transfer to a Microaerial Vehicle with a Microwave Active Phased Array

    Directory of Open Access Journals (Sweden)

    Shotaro Nako

    2014-01-01

    Full Text Available A wireless power transfer system using a microwave active phased array was developed. In the system, power is transferred to a circling microaerial vehicle (MAV by a microwave beam of 5.8 GHz, which is formed and directed to the MAV using an active phased array antenna. The MAV is expected to support observation of areas that humans cannot reach. The power beam is formed by the phased array with eight antenna elements. Input power is about 5.6 W. The peak power density at 1,500 mm altitude was 2.63 mW/cm2. The power is sent to a circling MAV. Therefore, the transfer beam should be polarized circularly to achieve a constant power supply independent of its yaw angle. To minimize the polarization loss, a sequentially routed antenna (SRA was applied to the transmitter antenna. Results show that the axial ratio of 0.440 dB was accomplished and that power fluctuation was kept below 1%.

  4. Efficient Photocatalytic Activities of TiO2 Hollow Fibers with Mixed Phases and Mesoporous Walls

    Science.gov (United States)

    Hou, Huilin; Shang, Minghui; Wang, Lin; Li, Wenge; Tang, Bin; Yang, Weiyou

    2015-10-01

    Currently, Degussa P25, with the typical mixed phases of anatase and rutile TiO2, is widely applied as the commercial photocatalysts. However, there are still some of obstacles for the P25 nanoparticles with totally high photocatalytic activities, especially for the catalytic stability due to their inevitable aggregation of the nanoparticles when used as the photocatalysts. In the present work, we reported the exploration of a novel TiO2 photocatalyst, which could offer an ideal platform for synergetic combination of the mixed-phase composition, hollow architecture and mesoporous walls for the desired excellent photocatalytic efficiency and robust stability. The mesoporous TiO2 hollow nanofibers were fabricated via a facile single capillary electrospinning technique, in which the foaming agents were used for creating mesopores throughout the walls of the hollow fibers. The obtained hollow fibers exhibit a high purity and possess the mixed phases of 94.6% anatase and 5.4% rutile TiO2. As compared to P25, the as-fabricated mesoporous TiO2 hollow fibers exhibited much higher efficient photocatalytic activities and stabilities toward the hydrogen evolution with a rate of ~499.1 μmol g-1·h-1 and ~99.5% degradation Rhodamine B (RhB) in 60 min, suggesting their promising application in efficient photocatalysts.

  5. Solar activity phase diagram and forecast of the coming 23rd cycle.

    Science.gov (United States)

    Pankratov, A. K.; Narmanskij, V. Ya.; Vladimirskij, B. M.

    1998-10-01

    The phase diagram method is used for investigation of relations between planetary dynamics and solar activity variations. It was found that the calculated moments of solar activity maxima/minima are disposed regularly in the coordinates of the difference of heliocentric longitudes of Uranus-Neptune versus the difference of heliocentric longitudes of Saturn-Neptune. There are separate zones containing maxima (minima) of only the northern (or southern) polarity of solar mean magnetic field. There is also a region where only maxima of small amplitudes are concentrated (Rz cycle. The minimum of activity must be observed in 1999±2. The maximum is forecast in 2006±2. The amplitude Rz can be as small as 60±20. Probably there will be no change of the polarity of the mean solar magnetic field.

  6. Active illumination using a digital micromirror device for quantitative phase imaging

    CERN Document Server

    Shin, Seungwoo; Yoon, Jonghee; Park, YongKeun

    2015-01-01

    We present a powerful and cost-effective method for active illumination using a digital micromirror device (DMD) for quantitative phase imaging techniques. Displaying binary illumination patterns on a DMD with appropriate spatial filtering, plane waves with various illumination angles are generated and impinged onto a sample. Complex optical fields of the sample obtained with various incident angles are then measured via Mach-Zehnder interferometry, from which a high-resolution two-dimensional synthetic aperture phase image and a three-dimensional refractive index tomogram of the sample are reconstructed. We demonstrate the fast and stable illumination control capability of the proposed method by imaging colloidal spheres and biological cells, including a human red blood cell and a HeLa cell.

  7. Density-matrix renormalization-group study of current and activity fluctuations near nonequilibrium phase transitions.

    Science.gov (United States)

    Gorissen, Mieke; Hooyberghs, Jef; Vanderzande, Carlo

    2009-02-01

    Cumulants of a fluctuating current can be obtained from a free-energy-like generating function, which for Markov processes equals the largest eigenvalue of a generalized generator. We determine this eigenvalue with the density-matrix renormalization group for stochastic systems. We calculate the variance of the current in the different phases, and at the phase transitions, of the totally asymmetric exclusion process. Our results can be described in the terms of a scaling ansatz that involves the dynamical exponent z . We also calculate the generating function of the dynamical activity (total number of configuration changes) near the absorbing-state transition of the contact process. Its scaling properties can be expressed in terms of known critical exponents. PMID:19391693

  8. Hybrid Modulation of Bidirectional Three-Phase Dual-Active-Bridge DC Converters for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Yen-Ching Wang

    2016-06-01

    Full Text Available Bidirectional power converters for electric vehicles (EVs have received much attention recently, due to either grid-supporting requirements or emergent power supplies. This paper proposes a hybrid modulation of the three-phase dual-active bridge (3ΦDAB converter for EV charging systems. The designed hybrid modulation allows the converter to switch its modulation between phase-shifted and trapezoidal modes to increase the conversion efficiency, even under light-load conditions. The mode transition is realized in a real-time manner according to the charging or discharging current. The operation principle of the converter is analyzed in different modes and thus design considerations of the modulation are derived. A lab-scaled prototype circuit with a 48V/20Ah LiFePO4 battery is established to validate the feasibility and effectiveness.

  9. Activated scaling in disorder-rounded first-order quantum phase transitions

    Science.gov (United States)

    Bellafard, Arash; Chakravarty, Sudip

    2016-09-01

    First-order phase transitions, classical or quantum, subject to randomness coupled to energylike variables (bond randomness) can be rounded, resulting in continuous transitions (emergent criticality). We study perhaps the simplest such model, the quantum three-color Ashkin-Teller model, and show that the quantum critical point in (1 +1 ) dimension is an unusual one, with activated scaling at the critical point and Griffiths-McCoy phase away from it. The behavior is similar to the transverse random field Ising model, even though the pure system has a first-order transition in this case. We believe that this fact must be attended to when discussing quantum critical points in numerous physical systems.

  10. The inactive-active phase transition in the noisy additive (exclusive-or) probabilistic cellular automaton

    Science.gov (United States)

    Mendonça, J. Ricardo G.

    2016-07-01

    We investigate the inactive-active phase transition in an array of additive (exclusive-or) cellular automata (CA) under noise. The model is closely related with the Domany-Kinzel (DK) probabilistic cellular automaton (PCA), for which there are rigorous as well as numerical estimates on the transition probabilities. Here, we characterize the critical behavior of the noisy additive cellular automaton by mean field analysis and finite-size scaling and show that its phase transition belongs to the directed percolation universality class of critical behavior. As a by-product of our analysis, we argue that the critical behavior of the noisy elementary CA 90 and 102 (in Wolfram’s enumeration scheme) must be the same. We also perform an empirical investigation of the mean field equations to assess their quality and find that away from the critical point (but not necessarily very far away) the mean field approximations provide a reasonably good description of the dynamics of the PCA.

  11. Development of Radar Control system for Multi-mode Active Phased Array Radar for atmospheric probing

    Science.gov (United States)

    Yasodha, Polisetti; Jayaraman, Achuthan; Thriveni, A.

    2016-07-01

    Modern multi-mode active phased array radars require highly efficient radar control system for hassle free real time radar operation. The requirement comes due to the distributed architecture of the active phased array radar, where each antenna element in the array is connected to a dedicated Transmit-Receive (TR) module. Controlling the TR modules, which are generally few hundreds in number, and functioning them in synchronisation, is a huge task during real time radar operation and should be handled with utmost care. Indian MST Radar, located at NARL, Gadanki, which is established during early 90's, as an outcome of the middle atmospheric program, is a remote sensing instrument for probing the atmosphere. This radar has a semi-active array, consisting of 1024 antenna elements, with limited beam steering, possible only along the principle planes. To overcome the limitations and difficulties, the radar is being augmented into fully active phased array, to accomplish beam agility and multi-mode operations. Each antenna element is excited with a dedicated 1 kW TR module, located in the field and enables to position the radar beam within 20° conical volume. A multi-channel receiver makes the radar to operate in various modes like Doppler Beam Swinging (DBS), Spaced Antenna (SA), Frequency Domain Interferometry (FDI) etc. Present work describes the real-time radar control (RC) system for the above described active phased array radar. The radar control system consists of a Spartan 6 FPGA based Timing and Control Signal Generator (TCSG), and a computer containing the software for controlling all the subsystems of the radar during real-time radar operation and also for calibrating the radar. The main function of the TCSG is to generate the control and timing waveforms required for various subsystems of the radar. Important components of the RC system software are (i) TR module configuring software which does programming, controlling and health parameter monitoring of the

  12. Development of Radar Control system for Multi-mode Active Phased Array Radar for atmospheric probing

    Science.gov (United States)

    Yasodha, Polisetti; Jayaraman, Achuthan; Thriveni, A.

    2016-07-01

    Modern multi-mode active phased array radars require highly efficient radar control system for hassle free real time radar operation. The requirement comes due to the distributed architecture of the active phased array radar, where each antenna element in the array is connected to a dedicated Transmit-Receive (TR) module. Controlling the TR modules, which are generally few hundreds in number, and functioning them in synchronisation, is a huge task during real time radar operation and should be handled with utmost care. Indian MST Radar, located at NARL, Gadanki, which is established during early 90's, as an outcome of the middle atmospheric program, is a remote sensing instrument for probing the atmosphere. This radar has a semi-active array, consisting of 1024 antenna elements, with limited beam steering, possible only along the principle planes. To overcome the limitations and difficulties, the radar is being augmented into fully active phased array, to accomplish beam agility and multi-mode operations. Each antenna element is excited with a dedicated 1 kW TR module, located in the field and enables to position the radar beam within 20° conical volume. A multi-channel receiver makes the radar to operate in various modes like Doppler Beam Swinging (DBS), Spaced Antenna (SA), Frequency Domain Interferometry (FDI) etc. Present work describes the real-time radar control (RC) system for the above described active phased array radar. The radar control system consists of a Spartan 6 FPGA based Timing and Control Signal Generator (TCSG), and a computer containing the software for controlling all the subsystems of the radar during real-time radar operation and also for calibrating the radar. The main function of the TCSG is to generate the control and timing waveforms required for various subsystems of the radar. Important components of the RC system software are (i) TR module configuring software which does programming, controlling and health parameter monitoring of the

  13. Role of Activation Energy in Resistance Drift of Amorphous Phase Change Materials

    Directory of Open Access Journals (Sweden)

    Martin eWimmer

    2014-12-01

    Full Text Available The time evolution of the resistance of amorphous thin films of the phase change materials Ge2Sb2Te5, GeTe and AgIn-Sb2Te is measured during annealing at T=80°C. The annealing process is interrupted by several fast temperature dips to determine the changing temperature dependence of the resistance. This procedure enables us to identify to what extent the resistance increase over time can be traced back to an increase in activation energy EA or to a rise of the prefactor R*. We observe that, depending on the material, the dominating contribution to the increase in resistance during annealing can be either a change in activation energy (Ge2Sb2Te5 or a change in prefactor (AgIn-Sb2Te. In the case of GeTe, both contribute about equally. We conclude that any phenomenological model for the resistance drift in amorphous phase change materials that is based on the increase of one parameter alone (e.g. the activation energy cannot claim general validity.

  14. Water at Biological Phase Boundaries: Its Role in Interfacial Activation of Enzymes and Metabolic Pathways.

    Science.gov (United States)

    Damodaran, Srinivasan

    2015-01-01

    Many life-sustaining activities in living cells occur at the membrane-water interface. The pertinent questions that we need to ask are, what are the evolutionary reasons in biology for choosing the membrane-water interface as the site for performing and/or controlling crucial biological reactions, and what is the key physical principle that is very singular to the membrane-water interface that biology exploits for regulating metabolic processes in cells? In this chapter, a hypothesis is developed, which espouses that cells control activities of membrane-bound enzymes through manipulation of the thermodynamic activity of water in the lipid-water interfacial region. The hypothesis is based on the fact that the surface pressure of a lipid monolayer is a direct measure of the thermodynamic activity of water at the lipid-water interface. Accordingly, the surface pressure-dependent activation or inactivation of interfacial enzymes is directly related to changes in the thermodynamic activity of interfacial water. Extension of this argument suggests that cells may manipulate conformations (and activities) of membrane-bound enzymes by manipulating the (re)activity of interfacial water at various locations in the membrane by localized compression or expansion of the interface. In this respect, cells may use the membrane-bound hormone receptors, lipid phase transition, and local variations in membrane lipid composition as effectors of local compression and/or expansion of membrane, and thereby local water activity. Several experimental data in the literature will be reexamined in the light of this hypothesis. PMID:26438268

  15. A New Synchronous Reference Frame-Based Method for Single-Phase Shunt Active Power Filters

    DEFF Research Database (Denmark)

    Monfared, Mohammad; Golestan, Saeed; Guerrero, Josep M.

    2013-01-01

    This paper deals with the design of a novel method in the synchronous reference frame (SRF) to extract the reference compensating current for single-phase shunt active power filters (APFs). Unlike previous works in the SRF, the proposed method has an innovative feature that it does not need...... the fictitious current signal. Frequency-independent operation, accurate reference current extraction and relatively fast transient response are other key features of the presented strategy. The effectiveness of the proposed method is investigated by means of detailed mathematical analysis. The results confirm...

  16. Brain microsomal fatty acid elongation is increased in abcd1-deficient mouse during active myelination phase.

    Science.gov (United States)

    Morita, Masashi; Kawamichi, Misato; Shimura, Yusuke; Kawaguchi, Kosuke; Watanabe, Shiro; Imanaka, Tsuneo

    2015-12-01

    The dysfunction of ABCD1, a peroxisomal ABC protein, leads to the perturbation of very long chain fatty acid (VLCFA) metabolism and is the cause of X-linked adrenoleukodystrophy. Abcd1-deficient mice exhibit an accumulation of saturated VLCFAs, such as C26:0, in all tissues, especially the brain. The present study sought to measure microsomal fatty acid elongation activity in the brain of wild-type (WT) and abcd1-deficient mice during the course of development. The fatty acid elongation activity in the microsomal fraction was measured by the incorporation of [2-(14)C]malonyl-CoA into fatty acids in the presence of C16:0-CoA or C20:0-CoA. Cytosolic fatty acid synthesis activity was completely inhibited by the addition of N-ethylmaleimide (NEM). The microsomal fatty acid elongation activity in the brain was significantly high at 3 weeks after birth and decreased substantially at 3 months after birth. Furthermore, we detected two different types of microsomal fatty acid elongation activity by using C16:0-CoA or C20:0-CoA as the substrate and found the activity toward C20:0-CoA in abcd1-deficient mice was higher than the WT 3-week-old animals. These results suggest that during the active myelination phase the microsomal fatty acid elongation activity is stimulated in abcd1-deficient mice, which in turn perturbs the lipid composition in myelin. PMID:26108493

  17. Inhibition of protein kinase B activity induces cell cycle arrest and apoptosis during early G₁ phase in CHO cells.

    Science.gov (United States)

    van Opstal, Angélique; Bijvelt, José; van Donselaar, Elly; Humbel, Bruno M; Boonstra, Johannes

    2012-04-01

    Inhibition of PKB (protein kinase B) activity using a highly selective PKB inhibitor resulted in inhibition of cell cycle progression only if cells were in early G1 phase at the time of addition of the inhibitor, as demonstrated by time-lapse cinematography. Addition of the inhibitor during mitosis up to 2 h after mitosis resulted in arrest of the cells in early G1 phase, as deduced from the expression of cyclins D and A and incorporation of thymidine. After 24 h of cell cycle arrest, cells expressed the cleaved caspase-3, a central mediator of apoptosis. These results demonstrate that PKB activity in early G1 phase is required to prevent the induction of apoptosis. Using antibodies, it was demonstrated that active PKB translocates to the nucleus during early G1 phase, while an even distribution of PKB was observed through cytoplasm and nucleus during the end of G1 phase. PMID:22251027

  18. Low-activity waste envelope definitions for the TWRS Privatization Phase I Request For Proposal

    Energy Technology Data Exchange (ETDEWEB)

    Patello, G.K.; Lauerhass, L.; Myers, R.L.; Wiemers, K.D.

    1996-11-01

    Radioactive waste has been stored in large underground storage tanks at the Hanford Site since 1944. Approximately 212 million liters of waste containing approximately 240,000 metric tons of processed chemicals and 177 mega-curies of radionuclides are now stored in 177 tanks. These caustic wastes are in the form of liquids, slurries, saltcakes, and sludge. In 1991, the Tank Waste Remediation System (TWRS) Program was established to manage, retrieve, treat, immobilize, and dispose of these wastes in a safe, environmentally sound, and cost-effective manner. The Department of Energy (DOE) has believes that it is feasible to privatize portions of the TWRS Program. Under the privatization strategy embodied in the Request for Proposal (RFP), DOE will purchase services from a contractor-owned, contractor-operated facility under a fixed-price contract. Phase I of the TWRS privatization strategy is a proof-of-concept/commercial demonstration-scale effort. The objectives of Phase I are to demonstrate the technical and business viability of using privatized facilities to treat Hanford tank waste; define and maintain required levels of radiological, nuclear, process, and occupational safety; maintain environmental protection and compliance; and substantially reduce life-cycle costs and time required to treat Hanford tank waste. Three low-activity waste (LAW) envelopes are identified for Phase I of the privatization contract and are representative of the range of Hanford double-shelled tank (DST) waste.

  19. Treatability study using prompt gamma neutron activation analysis (PGNAA) technology, Phase I. Topical report

    Energy Technology Data Exchange (ETDEWEB)

    Congedo, T.V.; Dulloo, A.R.; Ruddy, F.H. [and others

    1995-06-01

    This report reviews the progress accomplished during Phase I of a two-phase project intended to demonstrate the use of Prompt Gamma Neutron Activation Analysis (PGNAA) as a technology for the characterization of hazardous and radioactive contaminants in concrete floors. A comprehensive experimental program was undertaken using the N-SCAN{trademark} PGNAA system, which was initially developed by Westinghouse for soil characterization, to determine the sensitivity of PGNAA for several contaminants in concrete. The experiments were performed in a test facility specially designed and constructed for this project. The lower limits of detection derived from the experimental data were encouraging for mercury, cadmium, uranium-238, thorium-232, technetium-99, chlorine, uranium-235 and chromium. These limits were achieved after modifications made to the original N-SCAN system significantly improved its sensitivity for elements located at or near the surface of concrete. With the implementation of additional performance-enhancing modifications scheduled in Phase II, the detection sensitivity of N-SCAN at the end of this project is expected to be at least one order of magnitude higher, allowing N-SCAN to become an effective characterization tool. N-SCAN has several important advantages over current characterization methods and technologies.

  20. Modulation of phase-II enzyme activities in benzene treated ovariectomized rats.

    Science.gov (United States)

    Verma, Yeshvandra; Rana, S V S

    2011-05-01

    The aim of the study was to determine the influence of ovariectomy on phase II enzymes viz. glutathione-S-transferase (GST), glutathione peroxidase (GPX) and catalase (CAT) in liver and kidney of female rats treated with benzene. The results showed the significant decrease of the GST and GPX activity in benzene treated rats after ovariectomy. However progesterone supplementation stimulated the activity of GST and GPX in liver and kidney of benzene treated non ovariectomized and ovariectomized rats. Progesterone supplementation to benzene treated ovariectomized rats helps to gain in CAT activity. Our results on DNA damage using single cell gel electrophoresis also confirmed our findings on antioxidant enzymes. The results showed that lack of protective progesterone against benzene toxicity is reflected in alterations in antioxidant enzyme activities. However progesterone therapy to benzene treated ovariectomized rats results in activating the antioxidant defence system. Since female workers are engaged in industrial sector, these results are important from occupational health point of view. Benzene exposure affects their reproductive health. Nevertheless, it could be modulated by suitable hormonal therapy. PMID:21787707

  1. Solution phase synthesis of halogenated graphene and the electrocatalytic activity for oxygen reduction reaction

    Institute of Scientific and Technical Information of China (English)

    Kuang-Hsu Wu; Da-Wei Wang; Qingcong Zeng; Yang Li; Ian R. Gentle

    2014-01-01

    Metal-free carbon electrocatalyts for the oxygen reduction reaction (ORR) are attractive for their high activity and economic advantages. However, the origin of the activity has never been clearly elucidated in a systematic manner. Halogen group elements are good candidates for elucidating the effect, although it has been a difficult task due to safety issues. In this report, we demonstrate the synthesis of Cl-, Br-and I-doped reduced graphene oxide through two solution phase syntheses. We have evaluated the effectiveness of doping and performed electrochemical measurements of the ORR activity on these halogenated graphene materials. Our results suggest that the high electroneg-ativity of the dopant is not the key factor for high ORR activity;both Br-and I-doped graphene pro-moted ORR more efficiently than Cl-doped graphene. Furthermore, an unexpected sulfur-doping in acidic conditions suggests that a high level of sulfide can degrade the ORR activity of the graphene material.

  2. Afferent-mediated modulation of the soleus muscle activity during the stance phase of human walking

    DEFF Research Database (Denmark)

    Nazarena, Mazzaro; Grey, Michael James; do Nascimento, Omar Feix;

    2006-01-01

    The aim of this study was to investigate the contribution of proprioceptive feedback to the amplitude modulation of the soleus muscle activity during human walking. We have previously shown that slow-velocity, small-amplitude ankle dorsiflexion enhancements and reductions applied during the stance......-mediated contribution from muscle group II afferents, cutaneous and proprioceptive afferents from the foot, and load-sensitive afferents to the soleus EMG. Slow-velocity, small-amplitude ankle trajectory modifications were combined with the pharmaceutical depression of group II polysynaptic pathways with tizanidine...... that the feedback from group II afferents, and possibly from load-sensitive afferents, contribute to the amplitude modulation of the soleus muscle activity during the stance phase of the step cycle. However, feedback from cutaneous afferents and instrinsic proprioceptive afferents from the foot does not seem...

  3. Design and control of an LCL-filter-based three-phase active rectifier

    DEFF Research Database (Denmark)

    Liserre, Marco; Blaabjerg, Frede; Hansen, Steffan

    2005-01-01

    This paper proposes a step-by-step procedure for designing the LCL filter of a front-end three-phase active rectifier. The primary goal is to reduce the switching frequency ripple at a reasonable cost, while at the same time achieving a high-performance front-end rectifier (as characterized...... by a rapid dynamic response and good stability margin). An example LCL filter design is reported and a filter has been built and tested using the values obtained from this design. The experimental results demonstrate the performance of the design procedure both for the LCL filter and for the rectifier...... a powerful tool to design an LCL-filter-based active rectifier while avoiding trial-and-error procedures that can result in having to build several filter prototypes....

  4. Interferometric Monitoring of Gamma-ray Bright Active Galactic Nuclei II: Frequency Phase Transfer

    CERN Document Server

    Algaba, Juan-Carlos; Lee, Sang-Sung; Byun, Do-Young; Kang, Sin-Cheol; Kim, Dae-Won; Kim, Jae-Young; Kim, Jeong-Sook; Kim, Soon-Wook; Kino, Motoki; Miyazaki, Atsushi; Park, Jong-Ho; Trippe, Sascha; Wajima, Kiyoaki

    2015-01-01

    The Interferometric Monitoring of Gamma-ray Bright Active galactic nuclei (iMOGABA) program provides not only simultaneous multifrequency observations of bright gamma-ray detected active galactic nuclei (AGN), but also covers the highest Very Large Baseline Interferometry (VLBI) frequencies ever being systematically monitored, up to 129 GHz. However, observation and imaging of weak sources at the highest observed frequencies is very challenging. In the second paper in this series, we evaluate the viability of the frequency phase transfer technique to iMOGABA in order to obtain larger coherence time at the higher frequencies of this program (86 and 129 GHz) and image additional sources that were not detected using standard techniques. We find that this method is applicable to the iMOGABA program even under non-optimal weather conditions.

  5. Transcriptome analysis of spermatogenically regressed, recrudescent and active phase testis of seasonally breeding wall lizards Hemidactylus flaviviridis.

    Directory of Open Access Journals (Sweden)

    Mukesh Gautam

    Full Text Available BACKGROUND: Reptiles are phylogenically important group of organisms as mammals have evolved from them. Wall lizard testis exhibits clearly distinct morphology during various phases of a reproductive cycle making them an interesting model to study regulation of spermatogenesis. Studies on reptile spermatogenesis are negligible hence this study will prove to be an important resource. METHODOLOGY/PRINCIPAL FINDINGS: Histological analyses show complete regression of seminiferous tubules during regressed phase with retracted Sertoli cells and spermatognia. In the recrudescent phase, regressed testis regain cellular activity showing presence of normal Sertoli cells and developing germ cells. In the active phase, testis reaches up to its maximum size with enlarged seminiferous tubules and presence of sperm in seminiferous lumen. Total RNA extracted from whole testis of regressed, recrudescent and active phase of wall lizard was hybridized on Mouse Whole Genome 8×60 K format gene chip. Microarray data from regressed phase was deemed as control group. Microarray data were validated by assessing the expression of some selected genes using Quantitative Real-Time PCR. The genes prominently expressed in recrudescent and active phase testis are cytoskeleton organization GO 0005856, cell growth GO 0045927, GTpase regulator activity GO: 0030695, transcription GO: 0006352, apoptosis GO: 0006915 and many other biological processes. The genes showing higher expression in regressed phase belonged to functional categories such as negative regulation of macromolecule metabolic process GO: 0010605, negative regulation of gene expression GO: 0010629 and maintenance of stem cell niche GO: 0045165. CONCLUSION/SIGNIFICANCE: This is the first exploratory study profiling transcriptome of three drastically different conditions of any reptilian testis. The genes expressed in the testis during regressed, recrudescent and active phase of reproductive cycle are in concordance

  6. Phase II activity of belinostat (PXD-101), carboplatin, and paclitaxel in women with previously treated ovarian cancer

    DEFF Research Database (Denmark)

    Dizon, Don S; Damstrup, Lars; Finkler, Neil J;

    2012-01-01

    Preclinical data show that belinostat (Bel) is synergistic with carboplatin and paclitaxel in ovarian cancer. To further evaluate the clinical activity of belinostat, carboplatin, and paclitaxel (BelCaP), a phase 1b/2 study was performed, with an exploratory phase 2 expansion planned specifically...

  7. Singularity of influence of stochastic and order phase structures on optical quality of gas-dynamic laser active medium flow

    Science.gov (United States)

    Kovalevsky, Valery O.; Lobachev, Vitaly V.

    2002-02-01

    Detail analysis of active medium flow structure is presented. Schlieren method photography of flow is processed to reconstruct parameters both stochastic and order phase components. Properties of random part including correlation function, spectrum of spatial frequency, scale of turbulence, are determined by digital filtering. It was possible to compare influence of random and regular phase distortions on radiation divergence structure.

  8. Phase of shear vibrations within cochlear partition leads to activation of the cochlear amplifier.

    Directory of Open Access Journals (Sweden)

    Jessica S Lamb

    Full Text Available Since Georg von Bekesy laid out the place theory of the hearing, researchers have been working to understand the remarkable properties of mammalian hearing. Because access to the cochlea is restricted in live animals, and important aspects of hearing are destroyed in dead ones, models play a key role in interpreting local measurements. Wentzel-Kramers-Brillouin (WKB models are attractive because they are analytically tractable, appropriate to the oblong geometry of the cochlea, and can predict wave behavior over a large span of the cochlea. Interest in the role the tectorial membrane (TM plays in cochlear tuning led us to develop models that directly interface the TM with the cochlear fluid. In this work we add an angled shear between the TM and reticular lamina (RL, which serves as an input to a nonlinear active force. This feature plus a novel combination of previous work gives us a model with TM-fluid interaction, TM-RL shear, a nonlinear active force and a second wave mode. The behavior we get leads to the conclusion the phase between the shear and basilar membrane (BM vibration is critical for amplification. We show there is a transition in this phase that occurs at a frequency below the cutoff, which is strongly influenced by TM stiffness. We describe this mechanism of sharpened BM velocity profile, which demonstrates the importance of the TM in overall cochlear tuning and offers an explanation for the response characteristics of the Tectb mutant mouse.

  9. Analysis of a phase synchronized functional network based on the rhythm of brain activities

    Institute of Scientific and Technical Information of China (English)

    Li Ling; Jin Zhen-Lan; Li Bin

    2011-01-01

    Rhythm of brain activities represents oscillations of postsynaptic potentials in neocortex, therefore it can serve as an indicator of the brain activity state. In order to check the connectivity of brain rhythm, this paper develops a new method of constructing functional network based on phase synchronization. Electroencephalogram (EEG) data were collected while subjects looking at a green cross in two states, performing an attention task and relaxing with eyes-open. The EEG from these two states was filtered by three band-pass filters to obtain signals of theta (4-7 Hz),alpha (8-13 Hz) and beta (14-30 Hz) bands. Mean resultant length was used to estimate strength of phase synchronization in three bands to construct networks of both states, and mean degree K and cluster coefficient C of networks were calculated as a function of threshold. The result shows higher cluster coefficient in the attention state than in the eyes-open state in all three bands, suggesting that cluster coefficient reflects brain state. In addition, an obvious fronto-parietal network is found in the attention state, which is a well-known attention network. These results indicate that attention modulates the fronto-parietal connectivity in different modes as compared with the eyes-open state. Taken together this method is an objective and important tool to study the properties of neural networks of brain rhythm.

  10. Vapour and Liquid-Phase Artemisia annua Essential Oil Activities against Several Clinical Strains of Candida.

    Science.gov (United States)

    Santomauro, Francesca; Donato, Rosa; Sacco, Cristiana; Pini, Gabriella; Flamini, Guido; Bilia, Anna Rita

    2016-07-01

    Candida spp. are often the cause of infection in immune-compromised individuals. They are characterized by a strong resistance to antimicrobial drugs and disinfectants. The activity of Artemisia annua essential oil against Candida spp. was determined by vapour contact and microdilution assay. The oil was characterized by the presence of oxygenated monoterpenes (more than 75 % of the constituents), mainly represented by the irregular monoterpene artemisia ketone (ca. 22 %), and the widespread monoterpenes 1,8 cineole (ca. 19 %) and camphor (ca. 17 %). Other representative constituents were artemisia alcohol (5.9 %), α-pinene (5.7 %), and pinocarvone (3.0 %). Thujone, a typical toxic constituent of the Artemisia species, was not detected. The results are reported as minimum inhibitory concentration, minimum fungicidal concentration, and diameter of inhibition zone obtained by the vapour diffusion assay. We tested 10 clinical Candida strains, coming from both clinical samples and international collections. The results show that the antifungal activity of A. annua is influenced by the type of method adopted. The inhibitory action of the essential oil was, in fact, higher in the vapour than in the liquid phase. Our results show an average minimum inhibitory concentration in the liquid phase of 11.88 µL/mL, while in the vapour phase, the growth of all Candida strains tested at a concentration of 2.13 µL/cm(3) was inhibited. A strain of Candida glabrata was found to be less susceptible to the liquid medium than the vapour assay (50 µL/mL vs. 0.64 µL/cm(3), respectively). Candida albicans and Candida dubliniensis were the most susceptible to the vapour test, while Candida parapsilosis was the most resistant. PMID:27286334

  11. Regional Heat Sources and the Active and Break Phases of Boreal Summer Intraseasonal Variability

    Energy Technology Data Exchange (ETDEWEB)

    Annamalai, H; Sperber, K R

    2003-12-15

    The boreal summer intraseasonal variability (BSISV) associated with the 30-50 day mode is represented by the co-existence of three components, poleward propagation of convection over the Indian and tropical west Pacific longitudes and eastward propagation along the equator. The hypothesis that the three components influence each other has been investigated using observed OLR, NCEP-NCAR reanalysis, and solutions from an idealized linear model. The null hypothesis is that the three components are mutually independent. Cyclostationary EOF (CsEOF) analysis is applied on filtered OLR to extract the life-cycle of the BSISV. The dominant mode of CsEOF is significantly tied to observed rainfall over the Indian subcontinent. The components of the heating patterns from CsEOF analysis serve as prescribed forcings for the linear model. This allows us to ascertain which heat sources and sinks are instrumental in driving the large-scale monsoon circulation during the BSISV life-cycle. We identify three new findings: (1) the circulation anomalies that develop as a Rossby wave response to suppressed convection over the equatorial Indian Ocean associated with the previous break phase of the BSISV precondition the ocean-atmosphere system in the western Indian Ocean and trigger the next active phase of the BSISV, (2) the development of convection over the tropical west Pacific forces descent anomalies to the west. This, in conjunction with the weakened cross-equatorial flow due to suppressed convective anomalies over the equatorial Indian Ocean reduce the tropospheric moisture over the Arabian Sea, and promote westerly wind anomalies that do not recurve over India. As a result the low-level cyclonic vorticity shifts from India to southeast Asia and break conditions are initiated over India, and (3) the circulation anomalies forced by equatorial Indian Ocean convective anomalies significantly influence the active/break phases over the tropical west Pacific. Our model solutions support

  12. Neotectonic activity at the Giant Gjallar Vent (Norwegian Sea) indicates a future phase of active fluid venting

    Science.gov (United States)

    Dumke, Ines; Berndt, Christian; Crutchley, Gareth; Couillard, Mélanie; Gay, Aurélien

    2013-04-01

    The Giant Gjallar Vent (GGV) is a hydrothermal vent complex that formed during the opening of the North Atlantic at about 55 Ma. Sill intrusions into Cretaceous organic-rich sediments led to the production and subsequent vigorous seafloor venting of methane. A later phase of fluid escape occurred in mid-Oligocene times. The GGV is characterised by two pipes of 440 m and 480 m in diameter that reach up to the Base Late Pliocene Unconformity (BLPU) between the Kai and Naust formations. The unconformity is strongly deformed over an area of c. 18,000 km² across the vent, with a positive relief of up to 38 m above the surrounding paleo-seafloor. The overlying sediments of the Naust Formation conformally drape this deformation, smoothing its relief to a maximum of 15 m at the modern seafloor. The sediment drape indicates present inactivity of the vent system, as does the absence of indicators of active fluid escape in the water column during RV METEOR cruise M87-2 in 2012. However, high-resolution 2D seismic and Parasound data from the same cruise, and exploration-type 3D seismic data acquired by Norsk Hydro, show several indications for recent to ongoing activity at the GGV. Beneath the BLPU, strong frequency attenuation and chaotic reflections indicate the presence of free gas. At the edges of the extent of chaotic reflections, subvertical faults cut the unconformity as well as horizons of the lower and middle Naust Formation, suggesting tectonic activity after deposition of these horizons. Neotectonic activity is further indicated by the extensive occurrence of shallow faults apparent in Parasound records in the immediate vicinity of the vent and up to 16 km away. Some of these faults reach the seafloor. The observed deformation and faults may be the result of fluids accumulating beneath the BLPU due to increased loading of the oozy Kai Formation by denser glacigenic Naust sediments. Because of the lower permeability of the Naust Formation, the unconformity acts as a

  13. Metal Nanoparticles Catalyzed Selective Carbon-Carbon Bond Activation in the Liquid Phase.

    Science.gov (United States)

    Ye, Rong; Yuan, Bing; Zhao, Jie; Ralston, Walter T; Wu, Chung-Yeh; Unel Barin, Ebru; Toste, F Dean; Somorjai, Gabor A

    2016-07-13

    Understanding the C-C bond activation mechanism is essential for developing the selective production of hydrocarbons in the petroleum industry and for selective polymer decomposition. In this work, ring-opening reactions of cyclopropane derivatives under hydrogen catalyzed by metal nanoparticles (NPs) in the liquid phase were studied. 40-atom rhodium (Rh) NPs, encapsulated by dendrimer molecules and supported in mesoporous silica, catalyzed the ring opening of cyclopropylbenzene at room temperature under hydrogen in benzene, and the turnover frequency (TOF) was higher than other metals or the Rh homogeneous catalyst counterparts. Comparison of reactants with various substitution groups showed that electron donation on the three-membered ring boosted the TOF of ring opening. The linear products formed with 100% selectivity for ring opening of all reactants catalyzed by the Rh NP. Surface Rh(0) acted as the active site in the NP. The capping agent played an important role in the ring-opening reaction kinetics. Larger particle size tended to show higher TOF and smaller reaction activation energy for Rh NPs encapsulated in either dendrimer or poly(vinylpyrrolidone). The generation/size of dendrimer and surface group also affected the reaction rate and activation energy. PMID:27322570

  14. High Performance Harmonic Isolation By Means of The Single-phase Series Active Filter Employing The Waveform Reconstruction Method

    DEFF Research Database (Denmark)

    Senturk, Osman Selcuk; Hava, Ahmet M.

    2009-01-01

    This paper proposes the Waveform Reconstruction Method (WRM), which is utilized in the single-phase Series Active Filter's (SAF's) control algorithm, in order to extract the load harmonic voltage component of voltage harmonic type single-phase diode rectifier loads. Employing WRM and the line...... current sampling delay reduction method (SDRM), a single-phase SAF compensated system provides higher harmonic isolation performance and higher stability margins compared to the system using conventional synchronous reference frame based methods. The analytical, simulation, and experimental studies of a 2.......5 kW single-phase SAF compensated system prove the theory....

  15. Fully characterization of an active optical filter based on an equivalent-phase-shifted DFB-SOA

    Science.gov (United States)

    Deng, Ye; Li, Ming; Shi, Nuannuan; Tang, Jian; Sun, Shuqian; Zhang, Lihong; Li, Wei; Zhu, Ninghua

    2016-10-01

    A fully characterization of an active optical filter based on an equivalent-phase-shifted DFB-SOA has been theoretically analyzed and experimentally demonstrated in this paper. By employing an optical vector network analyzer (OVNA), transmission characteristics of the equivalent-phase-shifted DFB-SOA are obtained. The influences of driven current on transmission characteristics of the equivalent-phase-shifted DFB-SOA are also investigated. In addition to the advantage of integration, the proposed equivalent-phase-shifted DFB-SOA also shows significant application in design of photonic devices for all-optical signal processing and computing.

  16. Enhancing physical activity in older adults receiving hospital based rehabilitation: a phase II feasibility study

    Directory of Open Access Journals (Sweden)

    Said Catherine M

    2012-06-01

    Full Text Available Abstract Background Older adults receiving inpatient rehabilitation have low activity levels and poor mobility outcomes. Increased physical activity may improve mobility. The objective of this Phase II study was to evaluate the feasibility of a randomized controlled trial (RCT of enhanced physical activity in older adults receiving rehabilitation. Methods Patients admitted to aged care rehabilitation with reduced mobility were randomized to receive usual care or usual care plus additional physical activity, which was delivered by a physiotherapist or physiotherapy assistant. The feasibility and safety of the proposed RCT protocol was evaluated. The primary clinical outcome was mobility, which was assessed on hospital admission and discharge by an assessor blinded to group assignment. To determine the most appropriate measure of mobility, three measures were trialled; the Timed Up and Go, the Elderly Mobility Scale and the de Morton Mobility Index. Results The protocol was feasible. Thirty-four percent of people admitted to the ward were recruited, with 47 participants randomised to a control (n = 25 or intervention group (n = 22. The rates of adverse events (death, falls and readmission to an acute service did not differ between the groups. Usual care therapists remained blind to group allocation, with no change in usual practice. Physical activity targets were met on weekdays but not weekends and the intervention was acceptable to participants. The de Morton Mobility Index was the most appropriate measure of mobility. Conclusions The proposed RCT of enhanced physical activity in older adults receiving rehabilitation was feasible. A larger multi-centre RCT to establish whether this intervention is cost effective and improves mobility is warranted. Trial registration The trial was registered with the ANZTCR (ACTRN12608000427370.

  17. High active gas (O2 or N2) pressure crystal growth and phase diagram of YBaCuO phase and GaN

    International Nuclear Information System (INIS)

    In this paper a review of the phase diagram studies of the YBaCuO and GaN systems under high active gas (O2 or N2) pressure is given. The P,T equilibrium conditions for three superconducting phases existing in YBaCuO system vary as a function of Cu content. Application of high O2 pressure allows crystal growth of the 124 and 247 compounds and high N2 pressure allows crystal growth of GaN. The authors discuss also indications that other YBaCuO compounds may exist

  18. Antifungal activity of clotrimazole against Candida albicans depends on carbon sources, growth phase and morphology.

    Science.gov (United States)

    Kasper, Lydia; Miramón, Pedro; Jablonowski, Nadja; Wisgott, Stephanie; Wilson, Duncan; Brunke, Sascha; Hube, Bernhard

    2015-07-01

    Vulvovaginal candidiasis, a superficial infection caused predominantly by the pathogenic fungus Candida albicans, is frequently treated with clotrimazole. Some drug formulations contain lactate for improved solubility. Lactate may modify C. albicans physiology and drug sensitivity by serving as a carbon source for the fungus and/or affecting local pH. Here, we explored the effects of lactate, in combination with pH changes, on C. albicans proliferation, morphology and clotrimazole sensitivity. Moreover, we determined the influence of growth phase and morphology per se on drug sensitivity. We showed that utilization of lactate as a carbon source did not promote fast fungal proliferation or filamentation. Lactate had no influence on clotrimazole-mediated killing of C. albicans in standard fungal cultivation medium but had an additive effect on the fungicidal clotrimazole action under in vitro vagina-simulative conditions. Moreover, clotrimazole-mediated killing was growth-phase and morphology dependent. Post-exponential cells were resistant to the fungicidal action of clotrimazole, whilst logarithmic cells were sensitive, and hyphae showed the highest susceptibility. Finally, we showed that treatment of pre-formed C. albicans hyphae with sublethal concentrations of clotrimazole induced a reversion to yeast-phase growth. As C. albicans hyphae are considered the pathogenic morphology during mucosal infections, these data suggest that elevated fungicidal activity of clotrimazole against hyphae plus clotrimazole-induced hyphae-to-yeast reversion may help to dampen acute vaginal infections by reducing the relative proportion of hyphae and thus shifting to a non-invasive commensal-like population. In addition, lactate as an ingredient of clotrimazole formulations may potentiate clotrimazole killing of C. albicans in the vaginal microenvironment. PMID:25976001

  19. A multi-harmonic amplitude and relative-phase controller for active sound quality control

    Science.gov (United States)

    Mosquera-Sánchez, Jaime A.; de Oliveira, Leopoldo P. R.

    2014-04-01

    Current active sound quality control systems aim at dealing with the amplitude level of the primary disturbance, e.g. sound pressure, forces, velocities and/or accelerations, which implicitly leads to Loudness control, regardless of the spectral structure of the disturbance. As far as multi-harmonic disturbances are concerned, auditory Roughness, arguably the most related psychoacoustic metric with rumbling perception in passenger cars, can be tackled not merely by dealing with magnitudes but also with the relative-phase of the narrowband components. This paper presents an adaptive control scheme conceived for dealing with multi-harmonic disturbances, which features the independent amplitude and/or relative-phase control of the input periodic components and an improved robustness to impulsive events. The adaptive control scheme is based on a frequency-domain delayless implementation of the complex-domain, least mean squares algorithm, whereof its convergence process is improved by using a forgetting factor. The control capabilities are evaluated numerically for single- and multiple-harmonic disturbances, including realistic internal combustion engine sound contaminated with noise and by impulsive events. By using long transfer paths obtained from a real vehicle mock-up, sound pressure level reductions of 39 dBSPL and the ability to displacing the relative-phase of a number of narrowband components between [-π,π] are accomplished by the proposed control scheme. The assessment of the results by using Zwicker-Loudness and auditory Roughness models shows that the proposed adaptive algorithm is able to accomplish and stably preserve various sound quality targets, after completion of the robust convergence procedure, regardless of impulsive events that can occur during the system operation.

  20. Preparation of Pt-Ru hydrophobic catalysts and catalytic activities for liquid phase catalytic exchange reaction

    International Nuclear Information System (INIS)

    Pt/C and Pt-Ru/C catalysts with different ratios of Pt to Ru were synthesized, using ethylene glycol as both the dispersant and reducing agent at 1-2 MPa by microwave-assisted method. The catalysts were characterized by XRD, TEM and XPS. The mean particle sizes of the Pt/C and Pt-Ru/C catalysts were 1.9-2.0 nm. Pt and Ru existed as Pt(0), Pt(II), Pt(IV), Ru(0) and Ru(IV) for Pt-Ru/C catalysts, respectively. The face-centered cubic structure of the active mental particles would be changed upon the addition of Ru gradually. Then polytetrafluoroethylene and carbon-supported Pt and Pt-Ru catalysts were supported on foamed nickel to obtain hydrophobic catalysts. The catalytic activity was increased for liquid phase catalytic exchange (LPCE) when uniform Pt based hydrophobic catalysts was mixed into appropriate Ru. Hydrogen isotope exchange reaction occurs between hydration layer(H2O)nH+(ads)(n≥2) and D atoms due to intact water molecules being on Pt surface for LPCE. Water molecules have a tendency to dissociate to OH(ads) and H(ads) on metal Ru surface, and there is the other reaction path for Pt-Ru binary catalysts, which is probably the main reason of the increase of the catalytic activity of the hydrophobic Pt-Ru catalyst. (authors)

  1. Liquid phase adsorption behavior of inulin-type fructan onto activated charcoal.

    Science.gov (United States)

    Li, Kecheng; Liu, Song; Xing, Ronge; Yu, Huahua; Qin, Yukun; Li, Pengcheng

    2015-05-20

    This study describes liquid phase adsorption characteristics of inulin-type fructan onto activated charcoal. Batch mode experiments were conducted to study the effects of pH, contact time, temperature and initial concentration of inulin. Nearly neutral solution (pH 6-8) was favorable to the adsorption and the equilibrium was attained after 40 min with the maximum adsorption Qmax 0.182 g/g (adsorbate/adsorbent) at 298 K. The experimental data analysis indicated that the adsorption process fitted well with the pseudo-second-order kinetic model (R(2) = 1) and Langmuir isotherms model (R(2) > 0.99). Thermodynamic parameters revealed that the adsorption process was spontaneous and exothermic with a physical nature. Inulin desorption could reach 95.9% using 50% ethanol solution and activated charcoal could be reused without significant losses in adsorption capacity. These results are of practical significance for the application of activated charcoal in the production and purification of inulin-type fructan.

  2. Single Phase Passive Rectification Versus Active Rectification Applied to High Power Stirling Engines

    Science.gov (United States)

    Santiago, Walter; Birchenough, Arthur G.

    2006-01-01

    Stirling engine converters are being considered as potential candidates for high power energy conversion systems required by future NASA explorations missions. These types of engines typically contain two major moving parts, the displacer and the piston, in which a linear alternator is attached to the piston to produce a single phase sinusoidal waveform at a specific electric frequency. Since all Stirling engines perform at low electrical frequencies (less or equal to 100 Hz), space explorations missions that will employ these engines will be required to use DC power management and distribution (PMAD) system instead of an AC PMAD system to save on space and weight. Therefore, to supply such DC power an AC to DC converter is connected to the Stirling engine. There are two types of AC to DC converters that can be employed, a passive full bridge diode rectifier and an active switching full bridge rectifier. Due to the inherent line inductance of the Stirling Engine-Linear Alternator (SE-LA), their sinusoidal voltage and current will be phase shifted producing a power factor below 1. In order to keep power the factor close to unity, both AC to DC converters topologies will implement power factor correction. This paper discusses these power factor correction methods as well as their impact on overall mass for exploration applications. Simulation results on both AC to DC converters topologies with power factor correction as a function of output power and SE-LA line inductance impedance are presented and compared.

  3. Synthesis and catalytic activity of the metastable phase of gold phosphide

    Science.gov (United States)

    Fernando, Deshani; Nigro, Toni A. E.; Dyer, I. D.; Alia, Shaun M.; Pivovar, Bryan S.; Vasquez, Yolanda

    2016-10-01

    Recently, transition metal phosphides have found new applications as catalysts for the hydrogen evolution reaction that has generated an impetus to synthesize these materials at the nanoscale. In this work, Au2P3 was synthesized utilizing the high temperature decomposition of tri-n-octylphosphine as a source of elemental phosphorous. Gold nanorods were used as morphological templates with the aim of controlling the shape and size of the resulting gold phosphide particles. We demonstrate that the surface capping ligand of the gold nanoparticle precursors can influence the purity and extent to which the gold phosphide phase will form. Gold nanorods functionalized with 1-dodecanethiol undergo digestive ripening to produce discrete spherical particles that exhibit reduced reactivity towards phosphorous, resulting in low yields of the gold phosphide. In contrast, gold phosphide was obtained as a phase pure product when cetyltrimethylammonium bromide functionalized gold nanorods are used instead. The Au2P3 nanoparticles exhibited higher activity than polycrystalline gold towards the hydrogen evolution reaction.

  4. The Chernobyl active phase: why the ''official view'' is wrong [Chernobyl accident

    International Nuclear Information System (INIS)

    The results of a new investigation into the active phase of the Chernobyl accident are summarised. This phase is defined as the period from the initial destruction of the core to the puzzling and very sharp drop in environmental radionuclide release about nine days later. The research was carried out at Chernobyl over 18 months in cooperation with scientists living there. Its objective was to examine the reliability of the official Soviet presentation at the IAEA post-accident review conference in August 1986. In order to reconstruct the events, four new spheres of information were brought together: a reappraisal of the effectiveness of the accident management actions taken to limit the consequences of the accident; a description of the remains of the reactor building and the solidified corium; results of radiochemical analyses of the melted fuel; and an analysis of radioisotope release dynamics. An alternative explanation for the bathtub shaped release curve has been arrived at and a rough release estimate made which confirms suspicions that the amount of radioactivity released into the environment was greater than that officially reported. (UK)

  5. First evidence of phase-contrast imaging with laboratory sources and active pixel sensors

    International Nuclear Information System (INIS)

    The aim of the present work is to achieve a first step towards combining the advantages of an innovative X-ray imaging technique-phase-contrast imaging (XPCi)-with those of a new class of sensors, i.e. CMOS-based active pixel sensors (APSs). The advantages of XPCi are well known and include increased image quality and detection of details invisible to conventional techniques, with potential application fields encompassing the medical, biological, industrial and security areas. Vanilla, one of the APSs developed by the MI-3 collaboration (see (http://mi3.shef.ac.uk)), was thoroughly characterised and an appropriate scintillator was selected to provide X-ray sensitivity. During this process, a set of phase-contrast images of different biological samples was acquired by means of the well-established free-space propagation XPCi technique. The obtained results are very encouraging and are in optimum agreement with the predictions of a simulation recently developed by some of the authors thus further supporting its reliability. This paper presents these preliminary results in detail and discusses in brief both the background to this work and its future developments

  6. Phase Retrieval Problem. Application to VLBI Mapping of Active Galactic Nuclei

    CERN Document Server

    Bajkova, A T

    2012-01-01

    The well-known phase problem which means image reconstruction from only spectrum magnitude without using any spectrum phase information is considered basically in application to VLBI mapping of compact extragalactic radio sources (active galactic nuclei). The method proposed for phaseless mapping is based on the reconstruction of the spectrum magnitude on the entire UV plane from the measured visibility magnitude on a limited set of points and the reconstruction of the sought-for image of the source by Fienup's error-reduction iterative algorithm from the spectrum magnitude reconstructed at the first stage. It is shown that the technique used ensures unique solution (within a class of equivalent functions) for AGNs with typical structure morphology "bright core + week jet". The method proposed can be used, for example, for imaging with ultra-high resolution using a space{ground radio interferometer with a space antenna in a very high orbit ("RadioAstron"). In this case, a multi-element interferometer essentia...

  7. Synthesis and Catalytic Activity of the Metastable Phase of Gold Phosphide

    Energy Technology Data Exchange (ETDEWEB)

    Fernando, Deshani; Nigro, Toni A. E.; Dyer, I. D.; Alia, Shaun M.; Pivovar, Bryan S.; Vasquez, Yolanda

    2016-10-01

    Recently, transition metal phosphides have found new applications as catalysts for the hydrogen evolution reaction that has generated an impetus to synthesize these materials at the nanoscale. In this work, Au2P3 was synthesized utilizing the high temperature decomposition of tri-n-octylphosphine as a source of elemental phosphorous. Gold nanorods were used as morphological templates with the aim of controlling the shape and size of the resulting gold phosphide particles. We demonstrate that the surface capping ligand of the gold nanoparticle precursors can influence the purity and extent to which the gold phosphide phase will form. Gold nanorods functionalized with 1-dodecanethiol undergo digestive ripening to produce discrete spherical particles that exhibit reduced reactivity towards phosphorous, resulting in low yields of the gold phosphide. In contrast, gold phosphide was obtained as a phase pure product when cetyltrimethylammonium bromide functionalized gold nanorods are used instead. The Au2P3 nanoparticles exhibited higher activity than polycrystalline gold towards the hydrogen evolution reaction.

  8. Continuation versus discontinuation of oxytocin in the active phase of labour

    DEFF Research Database (Denmark)

    Bor, Isil Pinar; Ledertoug, Susanne; Boie, Sidsel;

    2016-01-01

    OBJECTIVE: To investigate whether discontinuation of oxytocin infusion increases the duration of the active phase of labour and reduces maternal and neonatal complications. DESIGN: Randomised controlled trial. SETTING: Department of Obstetrics and Gynaecology, Regional Hospital of Randers, Denmark....... POPULATION: Women with singleton pregnancy in the vertex position undergoing labour induction or augmentation. METHODS: Two hundred women were randomised when cervical dilation was ≤4 cm to either continue or discontinue oxytocin infusion when cervical dilation reached 5 cm. MAIN OUTCOME MEASURES......). The incidence of fetal heart rate abnormalities (51 versus 20%) and uterine hyperstimulation (12 versus 2%) was significantly greater in the continued than the discontinued oxytocin group. The incidence of tachysystole, caesarean deliveries, postpartum haemorrhage, third degree perineal tears and adverse...

  9. Bio-optofluidics and Bio-photonics: Programmable Phase Optics activities at DTU Fotonik

    DEFF Research Database (Denmark)

    Bañas, Andrew Rafael; Palima, Darwin; Pedersen, Finn;

    We present ongoing research and development activities for constructing a compact next generation BioPhotonics Workstation and a Bio-optofluidic Cell Sorter (cell-BOCS) for all-optical micromanipulation platforms utilizing low numerical aperture beam geometries. Unlike conventional high NA optical...... tweezers, the BioPhotonics workstation is e.g. capable of long range 3D manipulation. This enables a variety of biological studies such as manipulation of intricate microfabricated assemblies or for automated and parallel optofluidic cell sorting. To further reduce its overhead, we propose ways of making...... the BioPhotonics Workstation platform more photon efficient by studying the 3D distribution of the counter propagating beams and utilizing the Generalized Phase Contrast (GPC) method for illuminating the applied spatial light modulators....

  10. Enhancement of Alkene Epoxidation Activity of Titanosilicates by Gas-Phase Ammonia Modification

    Institute of Scientific and Technical Information of China (English)

    张里艳; 徐乐; 孙晶晶; 蒋金刚; 刘月明; 吴海虹; 吴鹏

    2012-01-01

    Novel ammonia-treated titanosilicates have been prepared by heating the samples of Ti-MWW, TS-l and Ti-Beta under pure ammonia gas flow at 673 K for a period of time. The ammonia modification improved their catalytic performance in liquid-phase oxidations. Especially, the catalytic activities of ammonified Ti-MWW, N-Ti-MWW, were enhanced greatly in the epoxidation of 1-hexene with H2O2. The reason that the ammonia treat- ment played such an important role in post-modification of titanosilicate was investigated in details. In comparison to the parent Ti-MWW catalyst, N-Ti-MMW was more robust and produced less coke in oxidation reactions.

  11. Creation of reversed phase high-performance liquid chromatographic technique to assay platelet-activating factor

    Institute of Scientific and Technical Information of China (English)

    杨云梅; 曹红翠; 徐哲荣; 陈晓明

    2004-01-01

    Objective: To establish a new assay for platelet-activating factor (PAF), to compare it with bio-assay; and to discuss its significance in some elderly people diseases such as cerebral infarction and coronary heart disease. Methods: To measure PAF levels in 100 controls, 23 elderly patients with cerebral infarction and 65 cases with coronary heart disease by reversed phase high-performance liquid chromatographic technique (rHPLC). Results:rHPLC is more convenient, sensitive,specific, and less confusing, compared with bio-assay. The level of plasma PAF in patients with cerebral infarction was higher than that in the controls (P<0.01), and in patients with coronary heart disease. Conclusion: Detection of PAF with rHPLC is more reliable and more accurate. The new assay has important significance in PAF research.

  12. Creation of reversed phase high-performance liquid chromatographic technique to assay platelet-activating factor

    Institute of Scientific and Technical Information of China (English)

    杨云梅; 曹红翠; 徐哲荣; 陈晓明

    2004-01-01

    Objective: To establish a new assay for platelet-activating factor (PAF), to compare it with bio-assay; and to discuss its significance in some elderly people diseases such as cerebral infarction and coronary heart disease. Methods: To measure PAF levels in 100 controls, 23 elderly patients with cerebral infarction and 65 cases with coronary heart disease by reversed phase high-performance liquid chromatographic technique (rHPLC). Results: rHPLC is more convenient, sensitive, specific, and less confusing, compared with bio-assay. The level of plasma PAF in patients with cerebral infarction was higher than that in the controls (P<0.01), and in patients with coronary heart disease. Conclusion: Detection of PAF with rHPLC is more reliable and more accurate. The new assay has important significance in PAF research.

  13. Monte Carlo Analysis of the Commissioning Phase Maneuvers of the Soil Moisture Active Passive (SMAP) Mission

    Science.gov (United States)

    Williams, Jessica L.; Bhat, Ramachandra S.; You, Tung-Han

    2012-01-01

    The Soil Moisture Active Passive (SMAP) mission will perform soil moisture content and freeze/thaw state observations from a low-Earth orbit. The observatory is scheduled to launch in October 2014 and will perform observations from a near-polar, frozen, and sun-synchronous Science Orbit for a 3-year data collection mission. At launch, the observatory is delivered to an Injection Orbit that is biased below the Science Orbit; the spacecraft will maneuver to the Science Orbit during the mission Commissioning Phase. The delta V needed to maneuver from the Injection Orbit to the Science Orbit is computed statistically via a Monte Carlo simulation; the 99th percentile delta V (delta V99) is carried as a line item in the mission delta V budget. This paper details the simulation and analysis performed to compute this figure and the delta V99 computed per current mission parameters.

  14. Summary of the Advanced Reactor Design Criteria (ARDC) Phase 2 Activities

    Energy Technology Data Exchange (ETDEWEB)

    Holbrook, Mark Raymond [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-09-01

    This report provides an end-of-year summary reflecting the progress and status of proposed regulatory design criteria for advanced non-LWR designs in accordance with the Level 3 milestone in M3AT-15IN2001017 in work package AT-15IN200101. These criteria have been designated as ARDC, and they provide guidance to future applicants for addressing the GDC that are currently applied specifically to LWR designs. The report provides a summary of Phase 2 activities related to the various tasks associated with ARDC development and the subsequent development of example adaptations of ARDC for Sodium Fast Reactor (SFR) and modular High Temperature Gas-cooled Reactor (HTGR) designs.

  15. Coherent combining of fiber-laser-pumped frequency converters using all fiber electro-optic modulator for active phase control

    Science.gov (United States)

    Bourdon, P.; Durécu, A.; Canat, G.; Le Gouët, J.; Goular, D.; Lombard, L.

    2015-03-01

    Coherent beam combining (CBC) by active phase control could be useful for power scaling fiber-laser-pumped optical frequency converters like OPOs. However, a phase modulator operating at the frequency-converted wavelength is needed, which is non standard component. Fortunately, nonlinear conversion processes rely on a phase-matching condition correlating, not only the wave vectors of the coupled waves, but also their phases. This paper demonstrates that, using this phase correlation for indirect control of the phase, coherent combining of optical frequency converters is feasible using standard all-fibered electro-optic modulators. For the sake of demonstration, this new technique is experimentally applied twice for continuous wave second-harmonic-generator (SHG) combination: i) combining 2 SHG of 1.55-μm erbium-doped fiber amplifiers in PPLN crystals generating 775-nm beams; ii) combining 2 SHG of 1.064-μm ytterbium-doped fiber amplifiers in LBO crystals generating 532-nm beams. Excellent CBC efficiency is achieved on the harmonic waves in both these experiments, with λ/20 and λ/30 residual phase error respectively. In the second experiment, I/Q phase detection is added on fundamental and harmonic waves to measure their phase variations simultaneously. These measurements confirm the theoretical expectations and formulae of correlation between the phases of the fundamental and harmonic waves. Unexpectedly, in both experiments, when harmonic waves are phase-locked, a residual phase difference remains between the fundamen tal waves. Measurements of the spectrum of these residual phase differences locate them above 50 Hz, revealing that they most probably originate in fast-varying optical path differences induced by turbulence and acoustic-waves on the experimental breadboard.

  16. A Hybrid Estimator for Active/Reactive Power Control of Single-Phase Distributed Generation Systems with Energy Storage

    DEFF Research Database (Denmark)

    Pahlevani, Majid; Eren, Suzan; Guerrero, Josep M.;

    2016-01-01

    This paper presents a new active/reactive power closed-loop control system for a hybrid renewable energy generation system used for single-phase residential/commercial applications. The proposed active/reactive control method includes a hybrid estimator, which is able to quickly and accurately...

  17. The Cell Cycle: An Activity Using Paper Plates to Represent Time Spent in Phases of the Cell Cycle

    Science.gov (United States)

    Scherer, Yvette D.

    2014-01-01

    In this activity, students are given the opportunity to combine skills in math and geometry for a biology lesson in the cell cycle. Students utilize the data they collect and analyze from an online onion-root-tip activity to create a paper-plate time clock representing a 24-hour cell cycle. By dividing the paper plate into appropriate phases of…

  18. Stability and activity of carbon nanofiber-supported catalysts in the aqueous phase reforming of ethylene glycol

    NARCIS (Netherlands)

    Haasterecht, van T.; Ludding, C.C.I.; Jong, de K.P.; Bitter, J.H.

    2013-01-01

    Nickel, cobalt, copper and platinum nanoparticles supported on carbon nano-fibers were evaluated with respect to their stability, catalytic activity and selectivity in the aqueous phase reforming of ethylene glycol (230 ¿, autogenous pressure, batch reactor). The initial surface-specific activities

  19. Stability and activity of carbon nanofiber-supported catalysts in the aqueous phase reforming of ethylene glycol

    NARCIS (Netherlands)

    van Haasterecht, T.; Ludding, C.C.I.; de Jong, K.P.; Bitter, J.H.

    2013-01-01

    Nickel, cobalt, copper and platinum nanoparticles supported on carbon nano-fibers were evaluated with respect to their stability, catalytic activity and selectivity in the aqueous phase reforming of ethylene glycol (230 ◦C, autogenous pressure, batch reactor). The initial surface-specific activities

  20. A Path towards uncertainty assignment in an operational cloud phase algorithm from ARM vertically pointing active sensors

    Energy Technology Data Exchange (ETDEWEB)

    Riihimaki, Laura D.; Comstock, Jennifer M.; Anderson, K. K.; Holmes, Aimee E.; Luke, Edward

    2016-06-10

    Knowledge of cloud phase (liquid, ice, mixed, etc) is necessary to describe the radiative impact of clouds and their lifetimes, but is a property that is difficult to simulate correctly in climate models. One step towards improving those simulations is to make observations of cloud phase with sufficient accuracy to help constrain model representations of cloud processes. A variety of methods, based primarily on decision tree approaches, have been used to identify cloud phase from active remote sensors. These algorithms do not include uncertainty estimates, which contributes an unknown amount of uncertainty to the retrieval of cloud microphysical properties and to model parameterization development and evaluation. In this study, we outline a methodology using a Bayesian classifier to estimate the probabilities of cloud phase class from Atmospheric Radiation Measurement (ARM) vertically pointing active remote sensors. We also test the value of including higher moments of the cloud radar Doppler spectrum than are traditionally used operationally. Using training data of known phase from the Mixed-Phase Arctic Cloud Experiment (M-PACE) field campaign, we demonstrate a proof of concept for how the algorithm can be trained and run as an operational cloud phase retrieval. Over 95% of data is identified correctly for pure ice and liquid cases used in this study. Mixed-phase and snow cases are more problematic to identify correctly. When lidar data are not available, including additional information from the Doppler spectrum provides substantial improvement to the algorithm.

  1. p21 as a transcriptional co-repressor of S-phase and mitotic control genes.

    Directory of Open Access Journals (Sweden)

    Nuria Ferrándiz

    Full Text Available It has been previously described that p21 functions not only as a CDK inhibitor but also as a transcriptional co-repressor in some systems. To investigate the roles of p21 in transcriptional control, we studied the gene expression changes in two human cell systems. Using a human leukemia cell line (K562 with inducible p21 expression and human primary keratinocytes with adenoviral-mediated p21 expression, we carried out microarray-based gene expression profiling. We found that p21 rapidly and strongly repressed the mRNA levels of a number of genes involved in cell cycle and mitosis. One of the most strongly down-regulated genes was CCNE2 (cyclin E2 gene. Mutational analysis in K562 cells showed that the N-terminal region of p21 is required for repression of gene expression of CCNE2 and other genes. Chromatin immunoprecipitation assays indicated that p21 was bound to human CCNE2 and other p21-repressed genes gene in the vicinity of the transcription start site. Moreover, p21 repressed human CCNE2 promoter-luciferase constructs in K562 cells. Bioinformatic analysis revealed that the CDE motif is present in most of the promoters of the p21-regulated genes. Altogether, the results suggest that p21 exerts a repressive effect on a relevant number of genes controlling S phase and mitosis. Thus, p21 activity as inhibitor of cell cycle progression would be mediated not only by the inhibition of CDKs but also by the transcriptional down-regulation of key genes.

  2. Facile phase control for hydrothermal synthesis of anatase-rutile TiO{sub 2} with enhanced photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hong [Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237 (China); Shen, Xiaojun [Faculty of Chemistry & Material Engineering, Wenzhou University, 276 Xueyuan Road, Zhejiang Province, Wenzhou 325027 (China); Liu, Yongdi [State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resources and Environmental Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237 (China); Wang, Lingzhi [Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237 (China); Lei, Juying, E-mail: leijuying@ecust.edu.cn [State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resources and Environmental Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237 (China); Zhang, Jinlong, E-mail: jlzhang@ecust.edu.cn [Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237 (China)

    2015-10-15

    Mixed-phase TiO{sub 2} photocatalysts with different proportions of anatase and rutile have been successfully synthesized in an acidic hydrothermal system, using tartaric acid (C{sub 4}H{sub 6}O{sub 6}) as a phase content regulator and titanium trichloride (TiCl{sub 3}) as the titanium source. The obtained samples were characterized by X-ray diffraction spectroscopy (XRD), infrared spectroscopy (IR), scanning electron microscopy (SEM) and so on. The phase contents of anatase and rutile in the TiO{sub 2} particles were successfully controlled by simply adjusting the molar ratio of C{sub 4}H{sub 6}O{sub 6} to TiCl{sub 3}. And the regulation degree could be further controlled by the concentration of sodium chloride (NaCl) in the reaction system. In addition, the effect of the reaction time, hydrothermal temperature and acidity on the phase structure of as-prepared products have also been investigated. A mechanism was proposed to interpret the evolution of the phases based on the experimental results. Finally, the photocatalytic activity of the prepared TiO{sub 2} were evaluated by the degradation of Rhodamine B (RhB) and methyl orange (MO) in aqueous solutions. The mixed-phase TiO{sub 2} exhibited higher activity than pure phase TiO{sub 2}, and the catalyst containing 77% anatase and 23% rutile had the highest photocatalytic activity. The enhanced photocatalytic activity could be explained by the mixed-phase effect between anatase and rutile. - Highlights: • Mixed-phase TiO{sub 2} with tunable proportions of anatase and rutile were obtained. • C{sub 4}H{sub 6}O{sub 4} as phase content regulator and TiCl{sub 3} as the titanium source. • The ratio of anatase and rutile were controlled by tuning ratio of C{sub 4}H{sub 6}O{sub 6} to TiCl{sub 3}. • The regulation degree could be further controlled by the concentration of NaCl. • The mixed-phase TiO{sub 2} exhibited higher activity than pure phase TiO{sub 2}.

  3. A new two-phase media method for 226Ra activity measurement in water

    International Nuclear Information System (INIS)

    A new two-phase media method was developed for determination of 226Ra activity in water. The method was calibrated by applying 7 standard 226Ra waters with known activities. The method detects alphas in two media; 80 ml of water in a glass bottle with air or a non-polar liquid such as olive oil on top of the water. Alpha particles from 226Ra, 222Rn and progeny were detected by two polycarbonate track detectors (PCTDs) which were mounted on a holder inserted in the bottle so that one PCTD is placed in water and the other in air or in the non-polar liquid. The bottles were hermetically sealed and kept for 40 or 48 d. The PCTDs in the bottles shaken every other day enhanced the sensitivity of the measurements. The Calibration Factors for the standard 226Ra waters, air and olive oil above water are, respectively, (7.85 ± 0.25) x 10-3, (7.94 ± 0.13) x 10-3 and 3.02 x 10-2 tracks.cm-2 kBq-1 h-1 m3. (authors)

  4. Evolution of the Level of Sunspot Activity in Solar CyclesⅠ. Evolution in the Descending Phase

    Institute of Scientific and Technical Information of China (English)

    Jia-Long Wang

    2006-01-01

    Taking the 13-point smoothed monthly sunspot number, Ri, and the deviation of the 13 associated monthly sunspot numbers from the smoothed one, Di, as a number-pair describing the global level of sunspot activity, the evolution of the level is statistically studied for the period from the month which is just 48 months before the minimum to the minimum in the descending phase, using the observed data of Solar Cycles 10 to 22. Our results show (1) for 46 months (94%) of the studied 49 months it is found that for a given month, the distribution of the 13 pairs which come from the 13 solar cycles on a log Ri~Di plane may be fitted by a straight line with a correlation coefficient larger than the critical one at confidence levelα=5%, and for 36 months (73%) the fitting is even better, forα=1%;(2) time variations of these two parameters and their correlations in the studied period can be described respectively by functions of time, whose main trends may be expressed by a linear or simple curvilinear function; (3) the evolutionary path of the level of sunspot activity may be represented by a logarithmic function as log Ri=0.704 ln Di-0.291.

  5. Liquid phase conversion of Glycerol to Propanediol over highly active Copper/Magnesia catalysts

    Indian Academy of Sciences (India)

    Satyanarayana Murty Pudi; Abdul Zoeb; Prakash Biswas; Shashi Kumar

    2015-05-01

    In this work, a series of Cu/MgO catalysts with different copper metal loading were prepared by the precipitation-deposition method. Their catalytic behaviour was investigated for glycerol hydrogenolysis to 1,2-propanediol (1,2-PDO). The physico-chemical properties of the catalysts were characterized by various techniques such as BET surface area, X-ray diffraction (XRD), temperature programmed reduction (TPR), NH3-temperature programmed desorption (NH3-TPD) and scanning electron microscopy (SEM) methods. The characterization results showed that the copper metal was well-dispersed over MgO support and a new phase Cu-MgO was also identified from XRD results after calcination. The 25Cu/MgO (Cu:25 wt%) catalyst exhibited the highest glycerol conversion of 88.7% and 1,2-PDO selectivity of 91.7% at 210°C, 4.5MPa of hydrogen pressure after 12 h. The high glycerol conversion was mainly due to the Cu dispersion on MgO support and high acidic strength. Further, the effects of temperature, hydrogen pressure, catalyst loading and glycerol concentration were studied over 25Cu/MgO catalyst for optimization of reaction parameters. Kinetic study over highly active 25Cu/MgO catalyst showed that the reaction followed the pseudo second order rate with respect to glycerol and the apparent activation energy was found to be 28.7 ± 0.8 kcal/mol.

  6. Radio Afterglow Rebrightening: Evidence for Multiple Active Phases in Gamma-Ray Burst Central Engines

    CERN Document Server

    Li, L B; Rice, J

    2015-01-01

    The rebrightening phenomenon is an interesting feature in some X-ray, optical, and radio afterglows of gamma-ray bursts (GRBs). Here, we propose a possible energy-supply assumption to explain the rebrightenings of radio afterglows, in which the central engine with multiple active phases can supply at least two GRB pulses in a typical GRB duration time. Considering the case of double pulses supplied by the central engine, the double pulses have separate physical parameters, except for the number density of the surrounding interstellar medium (ISM). Their independent radio afterglows are integrated by the ground detectors to form the rebrightening phenomenon. In this work, we firstly simulate diverse rebrightening light curves under consideration of different and independent physical parameters. Using this assumption, we also give our best fit to the radio afterglow of GRB 970508 at three frequencies of 1.43, 4.86, and 8.46 GHz. We suggest that the central engine may be active continuously at a timescale longer...

  7. The effect of systemic antibiotics administered during the active phase of non-surgical periodontal therapy or after the healing phase: a systematic review

    Directory of Open Access Journals (Sweden)

    Aretuza FRITOLI

    2015-06-01

    Full Text Available Objective The aim of this systematic review was to compare the clinical effectiveness of systemic antibiotics administered in the active stage of periodontal treatment or after the healing phase. Material and Methods An electronic search was performed in the databases EMBASE, MEDLINE and Cochrane Central Register of Controlled Trials (CENTRAL, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA statement. A manual search of the reference list of selected studies and of review articles was also performed up to November 2013. Randomized Clinical Trials (RCT that evaluated the systemic administration of antibiotics as adjuvants to scaling and root planning (SRP at different phases of periodontal treatment were included. Systematic reviews and studies that evaluated subjects with systemic diseases and those that used subantimicrobial doses of antibiotics were excluded. Results The initial search identified 1,039 articles, of which seven were selected, and only one met the inclusion criteria. This study showed that subjects taking metronidazole and amoxicillin at the initial phase of treatment exhibited statistically significantly greater reduction in pocket depth and gain in clinical attachment level in initially deep sites (PD≥7 mm than subjects taking antibiotics after healing (p<0.05. This comparison was conducted 2 months after antibiotic intake, at the healing phase. Conclusion To date, only one short-term RCT has directly compared different moments of systemic antibiotics administration, as adjuncts to SRP, in the treatment of periodontitis. Although the results of this study suggested some benefits for antibiotics intake during the active phase of therapy, these findings need to be confirmed by larger placebo-controlled randomized clinical trials with longer follow-up periods.

  8. Preparation and photocatalytic activity of bicrystal phase TiO2 nanotubes containing TiO2-B and anatase

    Science.gov (United States)

    Huang, Chuanxi; Zhu, Kerong; Qi, Mengyao; Zhuang, Yonglong; Cheng, Chao

    2012-06-01

    Bicrystal phase TiO2 nanotubes (NTS) containing monoclinic TiO2-B and anatase were prepared by the hydrothermal reaction of anatase nanoparticles with NaOH aqueous solution and a heat treatment. Their structure was characterized by XRD, TEM and Raman spectra. The results showed that the bicrystal phase TiO2 NTS were formed after calcining H2Ti4O9·H2O NTS at 573 K. The bicrystal phase TiO2 NTS exhibit significantly higher photocatalytic activity than the single phase anatase NTS and Dessuga P-25 nanoparticles in the degradation of Methyl Orange aqueous solution under ultraviolet light irradiation, which is attributed to the large surface and interface areas of the bicrystal phase TiO2 NTS.

  9. Nondestructive Image Detection of Cracks for a Nuclear Fuel Plate by Using Active Thermal Phase

    Energy Technology Data Exchange (ETDEWEB)

    Park, Nak Kyu; Park, Seung Kyu; Baik, Sung Hoon; Lee, Yoon Sang; Cha, Byung Heon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kang, Young June [Chonbuk National University, Jeonju (Korea, Republic of)

    2012-05-15

    by using a flash lamp in pulsed thermography, and then the surface heat penetrates into the material. If there are internal cracks, heat-flow is obstructed. The pulsed thermography detects the flaws by using this heat-flow variation. By contrast, active lock-in thermography technique periodically heats a specimen by modulating the lamp power. An intensity crack image and a phase crack image are acquired by extracting the intensity information and phase information at the periodic frequency, respectively. The lock-in thermo-graphic technique usually provides an improved crack image compared to the pulsed thermography though it is time-consuming. A phase crack image is more widely used than the intensity because phase data is not depended on the thermal disequilibrium of the surface. In this paper, active lock-in infrared thermo-graphic technique is adopted to try to detect an internal crack image of a nuclear fuel plate specimen. The experimental result of this new inspection approach is described in this paper

  10. Identification of a novel downstream binding protein implicated in late-phase-specific activation of the adenovirus major late promotor.

    OpenAIRE

    Mondesert, G; Tribouley, C; Kedinger, C

    1992-01-01

    The adenovirus major late promotor (MLP) is induced to very high levels after the onset of the viral DNA replication. Previous studies have identified sequence elements located downstream of the MLP startsite (DE1, between +85 and +98; DE2, between +100 and +120) implicated, together with the upstream promoter element, in this late-phase-specific transcriptional activation. One protein (DEF, now renamed DEF-A), induced during the late phase of viral infection, has been identified and shown to...

  11. A Systematic Investigation of Quaternary Ammonium Ions as Asymmetric Phase Transfer Catalysts. Application of Quantitative Structure Activity/Selectivity Relationships

    OpenAIRE

    Denmark, Scott E.; Gould, Nathan D.; Wolf, Larry M

    2011-01-01

    While the synthetic utility of asymmetric phase transfer catalysis continues to expand, the number of proven catalyst types and design criteria remains limited. At the origin of this scarcity is a lack in understanding of how catalyst structural features affect the rate and enantioselectivity of phase transfer catalyzed reactions. Described in this paper is the development of quantitative structure-activity relationships (QSAR) and -selectivity relationships (QSSR) for the alkylation of a pro...

  12. Managing Innovative Projects - Dynamics of Managerial Activities in the Front-End and Development Phases of Innovation Process

    OpenAIRE

    Rekonen, Satu

    2013-01-01

    Although there is a widespread agreement on the significant inherent disparities between different phases of innovation process, current management research largely ignores the differences of innovative project phases in the prescriptions of appropriate managerial activities. Further, not much emphasis has been put on the actual practices and actions of project managers, i.e., what is it that project managers actually do to manage innovative projects on a daily basis? This study addresses thi...

  13. Abnormalities in the cellular phase of blood fibrinolytic activity in systemic lupus erythematosus and in venous thromboembolism

    International Nuclear Information System (INIS)

    Fibrinolytic activities of whole blood and plasma were determined by 125I-fibrin radiometric assay in 16 normal subjects, and in 11 patients with systemic lupus erythematosus (SLE), 14 with progressive systemic sclerosis (PSS), 23 with venous thromboembolic disease, and 20 patients awaiting elective surgery. Mean whole blood and plasma activities for patients with PSS, and for those awaiting elective surgery, were similar to normal values, as was the mean plasma activity in patients with SLE. However, mean whole blood activity in SLE was significantly decreased compared with normals (p less than 0.05), with mean plasma activity accounting for 44% of mean whole blood activity (compared with 17% in normal subjects), representing a 67% decrease in mean calculated cellular phase activity in SLE, when compared with normals. Since the numbers of cells (neutrophils, monocytes) possibly involved in cellular activity were not decreased, the findings suggest a functional defect in fibrinolytic activity of one or more blood cell types in SLE. An additional finding was the participation of the cellular phase as well as the well-known plasma phase of blood in the fibrinolytic response to thromboembolism

  14. Unpredictable chronic stress decreases inhibitory avoidance learning in Tuebingen long-fin zebrafish: stronger effects in the resting phase than in the active phase.

    Science.gov (United States)

    Manuel, Remy; Gorissen, Marnix; Zethof, Jan; Ebbesson, Lars O E; van de Vis, Hans; Flik, Gert; van den Bos, Ruud

    2014-11-01

    Zebrafish (Danio rerio Hamilton) are increasingly used as a model to study the effects of chronic stress on brain and behaviour. In rodents, unpredictable chronic stress (UCS) has a stronger effect on physiology and behaviour during the active phase than during the resting phase. Here, we applied UCS during the daytime (active phase) for 7 and 14 days or during the night-time (resting phase) for 7 nights in an in-house-reared Tuebingen long-fin (TLF) zebrafish strain. Following UCS, inhibitory avoidance learning was assessed using a 3 day protocol where fish learn to avoid swimming from a white to a black compartment where they will receive a 3 V shock. Latencies of entering the black compartment were recorded before training (day 1; first shock) and after training on day 2 (second shock) and day 3 (no shock, tissue sampling). Fish whole-body cortisol content and expression levels of genes related to stress, fear and anxiety in the telencephalon were quantified. Following 14 days of UCS during the day, inhibitory avoidance learning decreased (lower latencies on days 2 and 3); minor effects were found following 7 days of UCS. Following 7 nights of UCS, inhibitory avoidance learning decreased (lower latency on day 3). Whole-body cortisol levels showed a steady increase compared with controls (100%) from 7 days of UCS (139%), to 14 days of UCS (174%) to 7 nights of UCS (231%), suggestive of an increasing stress load. Only in the 7 nights of UCS group did expression levels of corticoid receptor genes (mr, grα, grβ) and of bdnf increase. These changes are discussed as adaptive mechanisms to maintain neuronal integrity and prevent overload, and as being indicative of a state of high stress load. Overall, our data suggest that stressors during the resting phase have a stronger impact than during the active phase. Our data warrant further studies on the effect of UCS on stress axis-related genes, especially grβ; in mammals this receptor has been implicated in

  15. An Overview of Mode of Action and Analytical Methods for Evaluation of Gas Phase Activities of Flame Retardants

    Directory of Open Access Journals (Sweden)

    Khalifah A. Salmeia

    2015-03-01

    Full Text Available The latest techniques used to prove, describe and analyze the gas phase activity of a fire retardant used in polymeric materials are briefly reviewed. Classical techniques, such as thermogravimetric analysis or microscale combustion calorimetry, as well as complex and advanced analytical techniques, such as modified microscale combustion calorimeter (MCC, molecular beam mass spectroscopy and vacuum ultra violet (VUV photoionization spectroscopy coupled with time of flight MS (TOF-MS, are described in this review. The recent advances in analytical techniques help not only in determining the gas phase activity of the flame-retardants but also identify possible reactive species responsible for gas phase flame inhibition. The complete understanding of the decomposition pathways and the flame retardant activity of a flame retardant system is essential for the development of new eco-friendly-tailored flame retardant molecules with high flame retardant efficiency.

  16. Absolute frequency synthesis of pulsed coherent light waves through phase-modulation active optical feedback.

    Science.gov (United States)

    Shimizu, K; Horiguchi, T; Koyamada, Y

    1996-11-15

    A novel method for the broadband absolute frequency synthesis of pulsed coherent lightwaves is demonstrated. It is based on pulse recirculation around an active optical feedback ring containing a delay-line fiber, an external phase modulator, an acousto-optic frequency shifter (AOFS), and a high-finesse Fabry-Perot étalon. The modulation frequency F(M) and the frequency shift F(AO) that are due to AOFS are designed so that their sum or difference equals the free-spectral range of the étalon and F(AO) is set at larger than the half-width at full maximum of its resonant peaks. If one of the peak frequencies is tuned to the frequency of the initial pulse, the frequency of the recirculating pulse jumps to the next peak for each round trip. In the experiment the absolute frequency is synthesized over a frequency span of 700 GHz around the initial stabilized frequency of the master laser.

  17. Solid-phase extraction of antioxidant compounds from commercial cranberry extract and its antiradical activity

    Directory of Open Access Journals (Sweden)

    Tumbas Vesna T.

    2007-01-01

    Full Text Available This study is concerned with the fractionation and determination of major antioxidant compounds (phenols, flavonoids, anthocyanins and vitamin C in commercial cranberry extract. The total content of phenolics, flavonoids and total and monomers of anthocyanins, determined spectrophotometrically, was 1.67 mg/g, 0.41 mg/g, 5.12 mg/g and 3.32 mg/g. The content of vitamin C, determined volumetrically, was 121.74 mg/g. Commercial cranberry extract was dissolved in 80 % acetone and the solution was fractionated using solid phase extraction (SPE in order to abstract vitamin C, neutral and acidic phenols. The free radical scavenging activity of the cranberry extract and its fractions was investigated on stable 2,2-diphenyl-1-picrylhydrazyl (DPPH and reactive hydroxyl radicals employing electron spin resonance (ESR spectroscopy. The most effective fractions were those containing vitamin C (AADPPH= AAOH=100%, neutral (AADPPH=89.50% and AAOH=43.11% and acidic (AADPPH=83.98% and AAOH=38.58% phenols. The presence of vitamin C, abstracted from cranberry extract, was determined by Fe(III-mediated ascorbate oxidation which yields characteristic ESR doublet spectrum of ascorbyl radical.

  18. Degradation of dyes by active species injected from a gas phase surface discharge

    International Nuclear Information System (INIS)

    A reactor, based on the traditional gas phase surface discharge (GPSD), is designed for degradation of dye wastewater in this study. The reactor is characterized by using the dye wastewater as a ground electrode. A spiral discharge electrode of stainless steel wire attached on the inside wall of a cylindrical insulating medium and the wastewater surrounding the insulating medium for simultaneous cooling of the discharge electrode constitute the reactor. The active chemical radicals generated by the discharge of the spiral electrode are injected into the water with the carrier gas. The removal of three organic dyes (including methyl red (MR), reactive brilliant blue (RBB) and cationic red (CR)) in aqueous solution is investigated. The effects of electrode configuration, discharge voltage and solution pH value on the decoloration efficiency of MR are discussed. The experimental results show that over 95% of decoloration efficiencies for all the dyes are obtained after several minutes of plasma treatment. 40% of chemical oxygen demand removal of MR is obtained after 8 min of discharge treatment. Furthermore, it is found that ozone mainly affects the removal of dyes and several aliphatic compounds are identified as the oxidation products of MR. The possible degradation pathways of MR by GPSD are proposed.

  19. Hard X-ray Spectrum of Mkn 421 during the Active Phase

    Indian Academy of Sciences (India)

    R. K. Manchanda

    2001-06-01

    Spectral measurement of Mkn 421 were made in the hard X-ray energy band of 20–200 keV using a high sensitivity, large area scintillation counter telescope on November 21, 2000 and these coincided with the onset of an active X-ray phase as seen in the ASM counting rates on board RXTE. The observed spectrum can not be fitted to a single power law similar to the PDS data of BeppoSAX. The data can be fitted both by a two component power-law function or a combination of an exponential function with a power law component at the high energies above 80 keV. We identify these components with those arising from the synchrotron self compton and the high energy power-law tail arising from the upgrading of the thermal photons due to multiple Compton scattering a la Cyg X-1. A comparison with the earlier data clearly suggests a spectral variability in the hard X-ray spectrum of the source. We propose a continuously flaring geometry for the source as the underlying mechanism for energy release.

  20. Solid-Phase Extraction of Sulfur Mustard Metabolites Using an Activated Carbon Fiber Sorbent.

    Science.gov (United States)

    Lee, Jin Young; Lee, Yong Han

    2016-01-01

    A novel solid-phase extraction method using activated carbon fiber (ACF) was developed and validated. ACF has a vast network of pores of varying sizes and microporous structures that result in rapid adsorption and selective extraction of sulfur mustard metabolites according to the pH of eluting solvents. ACF could not only selectively extract thiodiglycol and 1-methylsulfinyl-2-[2-(methylthio)-ethylsulfonyl]ethane eluting a 9:1 ratio of dichloromethane to acetone, and 1,1'-sulfonylbis[2-(methylsulfinyl)ethane] and 1,1'-sulfonylbis- [2-S-(N-acetylcysteinyl)ethane] eluting 3% hydrogen chloride in methanol, but could also eliminate most interference without loss of analytes during the loading and washing steps. A sample preparation method has been optimized for the extraction of sulfur mustard metabolites from human urine using an ACF sorbent. The newly developed extraction method was applied to the trace analysis of metabolites of sulfur mustard in human urine matrices in a confidence-building exercise for the analysis of biomedical samples provided by the Organisation for the Prohibition of Chemical Weapons. PMID:26364317

  1. Degradation of dyes by active species injected from a gas phase surface discharge

    Science.gov (United States)

    Li, Jie; Wang, Tiecheng; Lu, Na; Zhang, Dandan; Wu, Yan; Wang, Tianwei; Sato, Masayuki

    2011-06-01

    A reactor, based on the traditional gas phase surface discharge (GPSD), is designed for degradation of dye wastewater in this study. The reactor is characterized by using the dye wastewater as a ground electrode. A spiral discharge electrode of stainless steel wire attached on the inside wall of a cylindrical insulating medium and the wastewater surrounding the insulating medium for simultaneous cooling of the discharge electrode constitute the reactor. The active chemical radicals generated by the discharge of the spiral electrode are injected into the water with the carrier gas. The removal of three organic dyes (including methyl red (MR), reactive brilliant blue (RBB) and cationic red (CR)) in aqueous solution is investigated. The effects of electrode configuration, discharge voltage and solution pH value on the decoloration efficiency of MR are discussed. The experimental results show that over 95% of decoloration efficiencies for all the dyes are obtained after several minutes of plasma treatment. 40% of chemical oxygen demand removal of MR is obtained after 8 min of discharge treatment. Furthermore, it is found that ozone mainly affects the removal of dyes and several aliphatic compounds are identified as the oxidation products of MR. The possible degradation pathways of MR by GPSD are proposed.

  2. Working memory activation of neural networks in the elderly as a function of information processing phase and task complexity.

    Science.gov (United States)

    Charroud, Céline; Steffener, Jason; Le Bars, Emmanuelle; Deverdun, Jérémy; Bonafe, Alain; Abdennour, Meriem; Portet, Florence; Molino, François; Stern, Yaakov; Ritchie, Karen; Menjot de Champfleur, Nicolas; Akbaraly, Tasnime N

    2015-11-01

    Changes in working memory are sensitive indicators of both normal and pathological brain aging and associated disability. The present study aims to further understanding of working memory in normal aging using a large cohort of healthy elderly in order to examine three separate phases of information processing in relation to changes in task load activation. Using covariance analysis, increasing and decreasing neural activation was observed on fMRI in response to a delayed item recognition task in 337 cognitively healthy elderly persons as part of the CRESCENDO (Cognitive REServe and Clinical ENDOphenotypes) study. During three phases of the task (stimulation, retention, probe), increased activation was observed with increasing task load in bilateral regions of the prefrontal cortex, parietal lobule, cingulate gyrus, insula and in deep gray matter nuclei, suggesting an involvement of central executive and salience networks. Decreased activation associated with increasing task load was observed during the stimulation phase, in bilateral temporal cortex, parietal lobule, cingulate gyrus and prefrontal cortex. This spatial distribution of decreased activation is suggestive of the default mode network. These findings support the hypothesis of an increased activation in salience and central executive networks and a decreased activation in default mode network concomitant to increasing task load.

  3. Three-Dimensional Multiscale Modeling of Stable Intermediate State Formation Mechanism in a Single Active Layer- Phase Change Memory Cell

    Science.gov (United States)

    Dincer, Onur; Cinar, Ibrahim; Karakas, Vedat; Aslan, Ozgur Burak; Gokce, Aisha; Stipe, Barry; Katine, Jordan A.; Aktas, Gulen; Ozatay, Ozhan

    2014-03-01

    Phase change memory (PCM) appears as a potential memory technology with its superior scalability which could be enhanced by a boost in storage density via multiple-bit per cell functionality. Given the large contrast between set and reset states of a PCM cell it is yet unclear whether it is possible to create intermediate logic states reproducibly and controllably in a device with a single active phase change layer. Here we report the results of a 3D finite element model that pinpoints the direct effect of current distribution and the indirect effect of device top contact fabrication induced defects through modification of phase change kinetics (crystallite nucleation and growth rates) on stabilization of intermediate states. A comprehensive picture of the electrical, thermal and phase change dynamics is obtained using a multiphysics approach. Our study shows that homogeneous and heterogeneous phase transition can be induced in the active region such that nonuniform temperature distribution and modification of switching dynamics with various contact shapes and sizes play a major role in the stabilization of a mixed phase state. This work has been supported by the European Commission FP7 Marie Curie IRG grant: PCM-256281 and TUBITAK grant: 113F385.

  4. PSYCHOPHYSIOLOGICAL CHARACTERISTICS OF WOMEN IN DEPENDENCE ON THE OVARIOHORMONAL CYCLE PHASE AND PROGESTERONE ACTIVITY (PART 1)

    OpenAIRE

    K. B. Muravlyova; O. I. Kuzminova; S. E. Petrova; M. V. Skoraya; O. M. Bazanova

    2013-01-01

    With the aim to identify the effects of menstrual cycle phase on the cognitive and psycho-emotional characteristics in 78 women aged 18–27 years were studied in a within-subject design Half the subjects began during their follicular phase and half began during their luteal phase (LP). The level of psycho-emotional tension was lowest, but cognitive performance efficiency is a highest in LP that is associated with the highest saliva progesterone level.

  5. Controlling gradient phase distributions in a model of active antenna array with locally coupled elements

    Science.gov (United States)

    Mishagin, K. G.; Shalfeev, V. D.

    2006-12-01

    The regime of synchronization with a certain gradient phase distribution and the possibility of controlling such distribution in a linear array of oscillators coupled by phase-locked loops (PLLs) have been theoretically studied. It is shown that a constant phase progression can be controlled by manipulating collective dynamics, with oscillator eigenfrequencies and coupling coefficients being the control parameters. The proposed principle of control, based on the nonlinear dynamics of PLL-coupled oscillators, can be used in solving the problems of phasing and controlled beam scanning in antenna arrays operating in different frequency bands.

  6. Detection of neural correlates of self-paced motor activity using empirical mode decomposition phase locking analysis.

    Science.gov (United States)

    Sweeney-Reed, Catherine Marie; Nasuto, Slawomir Jaroslaw

    2009-10-30

    Transient episodes of synchronisation of neuronal activity in particular frequency ranges are thought to underlie cognition. Empirical mode decomposition phase locking (EMDPL) analysis is a method for determining the frequency and timing of phase synchrony that is adaptive to intrinsic oscillations within data, alleviating the need for arbitrary bandpass filter cut-off selection. It is extended here to address the choice of reference electrode and removal of spurious synchrony resulting from volume conduction. Spline Laplacian transformation and independent component analysis (ICA) are performed as pre-processing steps, and preservation of phase synchrony between synthetic signals, combined using a simple forward model, is demonstrated. The method is contrasted with use of bandpass filtering following the same pre-processing steps, and filter cut-offs are shown to influence synchrony detection markedly. Furthermore, an approach to the assessment of multiple EEG trials using the method is introduced, and the assessment of statistical significance of phase locking episodes is extended to render it adaptive to local phase synchrony levels. EMDPL is validated in the analysis of real EEG data, during finger tapping. The time course of event-related (de)synchronisation (ERD/ERS) is shown to differ from that of longer range phase locking episodes, implying different roles for these different types of synchronisation. It is suggested that the increase in phase locking which occurs just prior to movement, coinciding with a reduction in power (or ERD) may result from selection of the neural assembly relevant to the particular movement. PMID:19643135

  7. An assessment of cloud top thermodynamic phase products obtained from A-Train passive and active sensors

    Directory of Open Access Journals (Sweden)

    S. Zeng

    2013-09-01

    Full Text Available The A-Train observations provide an unprecedented opportunity for the production of high quality dataset describing cloud properties. We illustrate in this study the use of one year of coincident POLDER (Polarization and Directionality of the Earth Reflectance, MODIS (MODerate Resolution Imaging Spectroradiometer and CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization observations to establish a reference dataset for the description of cloud top thermodynamic phase at global scale. We present the results of an extensive comparison between POLDER and MODIS cloud top phase products and discuss those in view of cloud vertical structure and optical properties derived simultaneously from collocated CALIOP active measurements. These results allow to identify and quantify potential biases present in the 3 considered dataset. Among those, we discuss the impacts of observation geometry, thin cirrus in multilayered and single layered cloud systems, supercooled liquid droplets, aerosols, fractional cloud cover and snow/ice or bright surfaces on global statistics of cloud phase derived from POLDER and MODIS passive measurements. Based on these analysis we define criteria for the selection of high confidence cloud phase retrievals which in turn can serve for the establishment of a reference cloud phase product. This high confidence joint product derived from POLDER/PARASOL and MODIS/Aqua can be used in the future as a benchmark for the evaluation of other cloud climatologies, for the assessment of cloud phase representation in models and the development of better cloud phase parametrization in the general circulation models (GCMs.

  8. Electron-irradiation induced changes in the phases and photocatalytic activity of TiO2 nanoparticles

    Science.gov (United States)

    Sapnar, K. B.; Dhole, S. D.; Bhoraskar, V. N.

    2012-04-01

    Samples of TiO2 nanoparticles, with mixed anatase and rutile phases, were irradiated with 6.5 MeV electrons at fluences, 1.5, 2.0, 2.5, 3.0, and 3.5 × 1015 e cm-2 and characterized by several methods. With increasing electron fluence, a continuous decrease in the average particle size from ˜80 nm to around 30 nm were observed along with a decrease in the rutile and the anatase phases of TiO2, but at different rates, and growth of the TiO2 brookite phase at slow rate. The photocatalytic activities of different electron irradiated TiO2 samples, in the photodegradation of methylene blue, were studied by recording UV-Vis absorption spectra of the respective solutions. On electron irradiation, even though the rutile phase in the TiO2 was decreasing, the photocatalytic activity of the nanoparticles increased continuously with fluence up to ˜3.0 × 1015 e cm-2, but decreased at 3.5 × 1015 e cm-2. The energy levels introduced by the brookite phase and the electron induced defects in TiO2 could have effectively reduced the electron-hole recombination rate in the absence of the rutile phase. The observed enhancement in the photocatalytic activity of the irradiated TiO2 is attributed to the formation of small size particles, the introduction of the oxygen related vacancies and other defects, the growth of the brookite phase, and increased absorption of radiation over the ultraviolet and visible range.

  9. Actively phase-controlled coupling between plasmonic waveguides via in-between gain-assisted nanoresonator: nanoscale optical logic gates.

    Science.gov (United States)

    Ho, Kum-Song; Han, Yong-Ha; Ri, Chol-Song; Im, Song-Jin

    2016-08-15

    The development of nanoscale optical logic gates has attracted immense attention due to increasing demand for ultrahigh-speed and energy-efficient optical computing and data processing, however, suffers from the difficulty in precise control of phase difference of the two optical signals. We propose a novel conception of nanoscale optical logic gates based on actively phase-controlled coupling between two plasmonic waveguides via an in-between gain-assisted nanoresonator. Precise control of phase difference between the two plasmonic signals can be performed by manipulating pumping rate at an appropriate frequency detuning, enabling a high contrast between the output logic states "1" and "0." Without modification of the structural parameters, different logic functions can be provided. This active nanoscale optical logic device is expected to be quite energy-efficient with ideally low energy consumption on the order of 0.1 fJ/bit. Analytical calculations and numerical experiments demonstrate the validity of the proposed concept.

  10. Phase Resetting Light Pulses Induce Per1 and Persistent Spike Activity in a Subpopulation of Biological Clock Neurons

    OpenAIRE

    Kuhlman, Sandra J.; Silver, Rae; Le Sauter, Joseph; Bult-Ito, Abel; McMahon, Douglas G.

    2003-01-01

    The endogenous circadian clock of the mammalian suprachiasmatic nucleus (SCN) can be reset by light to synchronize the biological clock of the brain with the external environment. This process involves induction of immediate-early genes such as the circadian clock gene Period1 (Per1) and results in a stable shift in the timing of behavioral and physiological rhythms on subsequent days. The mechanisms by which gene activation permanently alters the phase of clock neuron activity are unknown. T...

  11. Temporal phasing of locomotor activity, heart rate rhythmicity, and core body temperature is disrupted in VIP receptor 2-deficient mice

    DEFF Research Database (Denmark)

    Hannibal, Jens; Hsiung, Hansen M; Fahrenkrug, Jan

    2011-01-01

    Neurons of the brain's biological clock located in the hypothalamic suprachiasmatic nucleus (SCN) generate circadian rhythms of physiology (core body temperature, hormone secretion, locomotor activity, sleep/wake, and heart rate) with distinct temporal phasing when entrained by the light/dark (LD...

  12. VALIDATION REPORT (PHASE 2) FOR THE FISH SEXUAL DEVELOPMENT TEST FOR THE DETECTION OF ENDOCRINE ACTIVE SUBSTANCES

    DEFF Research Database (Denmark)

    Holbech, Henrik; Kinnberg, Karin Lund; Petersen, Gitte

    This document presents the validation report (phase 2) of the Fish Sexual Development Test (FSDT). The Fish Sexual Development Test (FSDT) covers a life-stage where sexual development is particularly sensitive to perturbation caused by endocrine active chemicals. The chemical exposure lasts...

  13. Phase I Final Report: Ultra-Low Background Alpha Activity Counter

    International Nuclear Information System (INIS)

    easily distinguish between these two risetimes and thereby count only alpha particles emitted by the sample. Alpha particles emitted from the sample tray are absorbed in the rear of the sample, so the tray's emissivity does not contribute to the background either. Extensions of the method to the counter's sidewalls similarly allow us to reject alpha particles emitted from the sidewalls. We can thus able obtain background rates over a factor of 1000 lower than in conventional instruments without active background rejection. Extending this principle to count at the 0.00001 alpha/cm2/hour, level encounters difficulties because there will typically be only 2.4 alpha particles per square meter per day. Since about 6 counts are required to measure activity at the 95% confidence level, large sample areas are required to make measurements in reasonable times. Unfortunately, increasing the counter's anode area to a square meter raises its capacitance so much that the preamplifier noise levels swamp the alpha particle signals and make counting impossible. In this SBIR we worked to solve this dilemma by segmenting the single large area electrode into several smaller, lower capacitance electrodes that could still detect the alpha particles reliably. Each electrode would have its own electronic and we would capture signals from all of them in coincidence (since an alpha track might well deposit charge on more than one electrode), a technique in which XIA is experienced. Therefore, in Phase I we worked to show proof of principle by subdividing our original 1,800 cm2 electrode into 4 square segments, each 625 cm2 and demonstrating that signal noise on individual channels reduced as expected. Because the Phase II counter with a 1 m2 segmented anode would require 16 segments plus a segmented guard as well, we also designed low cost signal processing electronics to instrument it in Phase II. Our Phase I effort met our major proof of principle goals. In particular, reducing the anode size

  14. Electron-irradiation induced changes in the phases and photocatalytic activity of TiO{sub 2} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Sapnar, K.B.; Dhole, S.D. [Department of Physics, University of Pune, Pune 411007 (India); Bhoraskar, V.N., E-mail: vnb@physics.unipune.ac.in [Department of Physics, University of Pune, Pune 411007 (India)

    2012-04-01

    Highlights: Black-Right-Pointing-Pointer The phases of TiO{sub 2} nanoparticles have been changed by electron irradiation. Black-Right-Pointing-Pointer The photocatalytic activity of TiO{sub 2} gets enhanced after electron irradiation. Black-Right-Pointing-Pointer The brookite phase has appeared in TiO{sub 2} after electron irradiation. - Abstract: Samples of TiO{sub 2} nanoparticles, with mixed anatase and rutile phases, were irradiated with 6.5 MeV electrons at fluences, 1.5, 2.0, 2.5, 3.0, and 3.5 Multiplication-Sign 10{sup 15} e cm{sup -2} and characterized by several methods. With increasing electron fluence, a continuous decrease in the average particle size from {approx}80 nm to around 30 nm were observed along with a decrease in the rutile and the anatase phases of TiO{sub 2}, but at different rates, and growth of the TiO{sub 2} brookite phase at slow rate. The photocatalytic activities of different electron irradiated TiO{sub 2} samples, in the photodegradation of methylene blue, were studied by recording UV-Vis absorption spectra of the respective solutions. On electron irradiation, even though the rutile phase in the TiO{sub 2} was decreasing, the photocatalytic activity of the nanoparticles increased continuously with fluence up to {approx}3.0 Multiplication-Sign 10{sup 15} e cm{sup -2}, but decreased at 3.5 Multiplication-Sign 10{sup 15} e cm{sup -2}. The energy levels introduced by the brookite phase and the electron induced defects in TiO{sub 2} could have effectively reduced the electron-hole recombination rate in the absence of the rutile phase. The observed enhancement in the photocatalytic activity of the irradiated TiO{sub 2} is attributed to the formation of small size particles, the introduction of the oxygen related vacancies and other defects, the growth of the brookite phase, and increased absorption of radiation over the ultraviolet and visible range.

  15. Activation of Metal-Organic Precursors by Electron Bombardment in the Gas Phase for Enhanced Deposition of Solid Films.

    Science.gov (United States)

    Sun, Huaxing; Qin, Xiangdong; Zaera, Francisco

    2012-09-01

    The incorporation of gas-phase electron-impact ionization and activation of metal-organic compounds into atomic layer deposition (ALD) processes is reported as a way to enhance film growth with stable precursors. Specifically, it is shown here that gas-phase activation of methylcyclopentadienylmanganese tricarbonyl, MeCpMn(CO)3, which was accomplished by using a typical nude ion gauge employed in many ultrahigh-vacuum (UHV) studies, enhances its dissociative adsorption on silicon surfaces, affording the design of ALD cycles with more extensive Mn deposition and at lower temperatures. Significantly higher Mn uptakes were demonstrated by X-ray photoelectron spectroscopy (XPS) on both silicon dioxide films and on Si(100) wafers Ar(+)-sputtered to remove their native oxide layer. The effectiveness of this electron-impact activation approach in ALD is explained in terms of the cracking patterns seen in mass spectrometry for the metal-organic precursor used.

  16. Enhancing the adsorption of vapor-phase mercury chloride with an innovative composite sulfur-impregnated activated carbon.

    Science.gov (United States)

    Ie, Iau-Ren; Chen, Wei-Chin; Yuan, Chung-Shin; Hung, Chung-Hsuang; Lin, Yuan-Chung; Tsai, Hsieh-Hung; Jen, Yi-Shiu

    2012-05-30

    Mercury chloride (HgCl(2)) is the major mercury derivate emitted from municipal solid waste incinerators, which has high risk to the environment and human health. This study investigated the adsorption of vapor-phase HgCl(2) with an innovative composite sulfurized activated carbon (AC), which was derived from the pyrolysis, activation, and sulfurization of waste tires. The composite sulfur-impregnation process impregnated activated carbon with aqueous-phase sodium sulfide (Na(2)S) and followed with vapor-phase elemental sulfur (S(0)). Thermogravimetric analysis (TGA) was applied to investigate the adsorptive capacity of vapor-phase HgCl(2) using the composite sulfurized AC. The operating parameters included the types of composite sulfurized AC, the adsorption temperature, and the influent HgCl(2) concentration. Experimental results indicated that the sulfur-impregnation process could increase the sulfur content of the sulfurized AC, but decreased its specific surface area. This study further revealed that the composite sulfurized AC impregnated with aqueous-phase Na(2)S and followed with vapor-phase S(0) (Na(2)S+S(0) AC) had much higher saturated adsorptive capacity of HgCl(2) than AC impregnated in the reverse sequence (S(0)+Na(2)S AC). A maximum saturated adsorptive capacity of HgCl(2) up to 5236 μg-HgCl(2)/g-C was observed for the composite Na(2)S+S(0) AC, which was approximately 2.00 and 3.17 times higher than those for the single Na(2)S and S(0) ACs, respectively.

  17. Effect of supercritical water treatment on porous structure, liquid-phase adsorption and regeneration characteristics of activated anthracite

    Energy Technology Data Exchange (ETDEWEB)

    Tanthapanichakoon, W.; Sittipraneed, S.; Japthong, P.; Charinpanitkul, T.; Boon-Amnuayvitaya, V.; Nakagawa, K.; Tamon, H. [National Nanotechnological Centre, Pathumthani (Thailand)

    2006-06-15

    Microporous activated anthracite was produced from waste anthracite powders by the conventional steam activation. The activated anthracite was also treated by supercritical water reaction (SWR) by using distilled water and hydrogen peroxide solution as a liquid medium for SWR treatment. It was found that SWR treatment can improve the mesoporosity of the activated anthracite though the micropore volume was reduced by the treatment. In liquid-phase adsorption and supercritical water regeneration studies, phenol and organic dye RED 31 were selected as the representative adsorbates. The adsorption and regeneration characteristics of activated anthracite were compared with those of a commercial activated carbon. The results indicate that the activated anthracite prepared showed comparable phenol adsorption capacity but significantly lower dye adsorption capacity than the commercial one. However, supercritical water regeneration efficiency was remarkably high. The first/second regeneration efficiencies of commercial activated carbon and activated anthracite exhausted with phenol were 55/55 and 65/65%, respectively, and in the case of RED 31, 78/79 and 338/317%, respectively, with losses of activated carbon less than 4% per regeneration. Because of little loss of activated carbon during successive regenerations, this SWR regeneration method was suitable for regenerating spent activated carbon or anthracite.

  18. Increasing the operating distance of a phase-shift laser range-finding system by using an active reflector

    Science.gov (United States)

    Hu, Pengcheng; Yu, Liang; Mei, Jianting; Tan, Jiubin

    2015-12-01

    A new phase-shift laser ranging method is developed by combining the conventional phase-shift ranging and the concept of transponder, in which the passive mirror in a phase-shift laser range-finding system is replaced with an active reflector whose light source power is the same as that at the measurement terminal. As a result, the power of the returned light is inversely proportional to the 2nd instead of the 4th power of the distance being measured. Section 3 indicate that by using the active reflector, the operating distance is dramatically increased without increasing the laser power or lens aperture. With a transmitted power of 20 mW and an aperture of 100 mm, the operating distance increased from 1.5 km to 9.4 km, and a 15-fold range gain can be forecasted for a transmitted power of 1 W. This strongly confirms the suitability of the developed phase-shift method with an active reflector for measuring longer distances.

  19. A repetitive control scheme aiming to compensate the 6k+1 harmonics for three-phase hybrid active filter

    DEFF Research Database (Denmark)

    Luo, Zhaoxu; Su, Mei; Yang, Jian;

    2016-01-01

    in stationary reference frame, which only compensates the 6k+1 harmonics (e.g. -5, +7, -11, +13) in three-phase systems and reduces the time delay to T0/6 . So compared with the earlier reduced delay time repetitive controllers, the robustness and transient performance is further improved, the waste of control...... effort is reduced, and the possibility of amplifying and even injecting any harmonic noises into system is avoided to the greatest extent. Moreover, the proposed repetitive scheme is used in the control of a three-phase hybrid active power filter. The experimental results validate the effectiveness...

  20. Accelerating Energy Efficiency in Indian Data Centers. Final Report for Phase I Activities

    Energy Technology Data Exchange (ETDEWEB)

    Ganguly, Suprotim [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Raje, Sanyukta [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kumar, Satish [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sartor, Dale [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Greenberg, Steve [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-01-01

    This report documents Phase 1 of the “Accelerating Energy Efficiency in Indian Data Centers” initiative to support the development of an energy efficiency policy framework for Indian data centers. The initiative is being led by the Confederation of Indian Industry (CII), in collaboration with Lawrence Berkeley National Laboratory (LBNL)-U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy, and under the guidance of Bureau of Energy Efficiency (BEE). It is also part of the larger Power and Energy Efficiency Working Group of the US-India Bilateral Energy Dialogue. The initiative consists of two phases: Phase 1 (November 2014 – September 2015) and Phase 2 (October 2015 – September 2016).

  1. Motility-induced phase separation of active particles in the presence of velocity alignment

    CERN Document Server

    Barre, Julien; Muratori, Massimiliano; Peruani, Fernando

    2014-01-01

    Self-propelled particle (SPP) systems are intrinsically out of equilibrium systems, where each individual particle converts energy into work to move in a dissipative medium. When interacting through a velocity alignment mechanism, and the medium acts as a momentum sink, even momentum is not conserved. In this scenario, a mapping into an equilibrium system seems unlikely. Here, we show that an entropy functional can be derived for SPPs with velocity alignment and density-dependent speed, at least in the (orientationally) disordered phase. This non-trivial result has important physical consequences. The study of the entropy functional reveals that the system undergoes phase separation above the orientational-order phase transition known to occur in SPP system with velocity alignment. Moreover, we indicate that the spinodal line is a function of the alignment sensitivity, diverging at the point where the orientational-order phase transition occurs. We show that density fluctuations also diverge as the orientatio...

  2. Phase transformation of Mg-calcite to aragonite in active-forming hot spring travertines

    Science.gov (United States)

    Greer, Heather F.; Zhou, Wuzong; Guo, Li

    2015-08-01

    A travertine specimen collected from the western part of Yunnan Province of China was subjected to microstructural analysis by powder X-ray diffraction, scanning electron microscopy, high resolution transmission electron microscopy and energy dispersive X-ray spectroscopy. A new formation mechanism was proposed whereby polycrystalline rhombohedral particles of magnesium-containing calcite underwent a phase transformation into sheaf-like clusters of aragonite microrods. It is proposed that a high concentration of magnesium ions and embedded biological matter poisoned the growth of calcite and therefore instigated the phase transformation of the core of the rhombohedral calcite particles to an aragonite phase with a higher crystallinity. The single crystalline aragonite microrods with a higher density than the Mg-calcite nanocrystallites grew at the expense of the latter to generate sheaf-like clusters. This newly discovered formation mechanism is expected to enhance previous knowledge on this geologically important phase transformation from a morphology point of view.

  3. Analysis of electrical performances of planar active phased array antennas with distorted array plane

    Institute of Scientific and Technical Information of China (English)

    Wang Congsi; Bao Hong; Zhang Fushun; Feng Xingang

    2009-01-01

    a planar phased array antenna with different distortions grades prove the validity of the model.Therefore,by the method,the antenna designers may set the reasonable requirement on the structural tolerance in manufacturing antenna.

  4. Lunar Phase Function at 1064 Nm from Lunar Orbiter Laser Altimeter Passive and Active Radiometry

    Science.gov (United States)

    Barker, M. K.; Sun, X.; Mazarico, E.; Neumann, G. A.; Zuber, M. T.; Smith, D. E.

    2016-01-01

    We present initial calibration and results of passive radiometry collected by the Lunar Orbiter Laser Altimeter onboard the Lunar Reconnaissance Orbiter over the course of 12 months. After correcting for time- and temperature-dependent dark noise and detector responsivity variations, the LOLA passive radiometry measurements are brought onto the absolute radiance scale of the SELENE Spectral Profiler. The resulting photometric precision is estimated to be 5%. We leverage the unique ability of LOLA to measure normal albedo to explore the 1064 nm phase function's dependence on various geologic parameters. On a global scale, we find that iron abundance and optical maturity (quantified by FeO and OMAT) are the dominant controlling parameters. Titanium abundance (TiO2), surface roughness on decimeter to decameter scales, and soil thermo- physical properties have a smaller effect, but the latter two are correlated with OMAT, indicating that exposure age is the driving force behind their effects in a globally-averaged sense. The phase function also exhibits a dependence on surface slope at approximately 300 m baselines, possibly the result of mass wasting exposing immature material and/or less space weathering due to reduced sky visibility. Modeling the photometric function in the Hapke framework, we find that, relative to the highlands, the maria exhibit decreased backscattering, a smaller opposition effect (OE) width, and a smaller OE amplitude. Immature highlands regolith has a higher backscattering fraction and a larger OE width compared to mature highlands regolith. Within the maria, the backscattering fraction and OE width show little dependence on TiO2 and OMAT. Variations in the phase function shape at large phase angles are observed in and around the Copernican-aged Jackson crater, including its dark halo, a putative impact melt deposit. Finally, the phase function of the Reiner Gamma Formation behaves more optically immature than is typical for its composition

  5. NASA's UAS Integration into the NAS: A Report on the Human Systems Integration Phase 1 Simulation Activities

    Science.gov (United States)

    Fern, Lisa; Rorie, R. Conrad; Shively, R. Jay

    2014-01-01

    In 2011 the National Aeronautics and Space Administration (NASA) began a five-year Project to address the technical barriers related to routine access of Unmanned Aerial Systems (UAS) in the National Airspace System (NAS). Planned in two phases, the goal of the first phase was to lay the foundations for the Project by identifying those barriers and key issues to be addressed to achieve integration. Phase 1 activities were completed two years into the five-year Project. The purpose of this paper is to review activities within the Human Systems Integration (HSI) subproject in Phase 1 toward its two objectives: 1) develop GCS guidelines for routine UAS access to the NAS, and 2) develop a prototype display suite within an existing Ground Control Station (GCS). The first objective directly addresses a critical barrier for UAS integration into the NAS - a lack of GCS design standards or requirements. First, the paper describes the initial development of a prototype GCS display suite and supporting simulation software capabilities. Then, three simulation experiments utilizing this simulation architecture are summarized. The first experiment sought to determine a baseline performance of UAS pilots operating in civil airspace under current instrument flight rules for manned aircraft. The second experiment examined the effect of currently employed UAS contingency procedures on Air Traffic Control (ATC) participants. The third experiment compared three GCS command and control interfaces on UAS pilot response times in compliance with ATC clearances. The authors discuss how the results of these and future simulation and flight-testing activities contribute to the development of GCS guidelines to support the safe integration of UAS into the NAS. Finally, the planned activities for Phase 2, including an integrated human-in-the-loop simulation and two flight tests are briefly described.

  6. Involvement of activated leukocytes in the regulation of plasma levels of acute phase proteins in microgravity simulation experiments

    Science.gov (United States)

    Larina, Olga; Bekker, Anna; Turin-Kuzmin, Alexey

    2016-07-01

    Earth-based studies of microgravity effects showed the induction of the mechanisms of acute phase reaction (APR). APR comprises the transition of stress-sensitive protein kinases of macrophages and other responsive cells into the active state and the phosphorylation of transcription factors which in turn stimulate the production of acute-phase reaction cytokines. Leukocyte activation is accompanied by the acceleration of the formation of oxygen radicals which can serve a functional indice of leukocyte cell state. The series of events at acute phase response result in selective changes in the synthesis of a number of secretory blood proteins (acute phase proteins, APPs) in liver cells thus contributing the recovery of homeostasis state in the organism. Earlier experiment with head-down tilt showed the increase in plasma concentrations of two cytokine mediators of acute phase response, tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) being the outcome of the activation of producer cells, foremost, leukocytes. In experiment with 4-day dry immersion chemiluminescent (ChL) reply of the whole blood samples to a test stimulus were studied along with the measurements of plasma levels of APPs, namely, alpha1-antitrypsin (alpha1-AT), alpha1-acid glycoprotein (alpha1-AGP), alpha2-macroglobulin (alpha2-M), ceruloplasmin (Cer), haptoglobin (Hp), C3-complement component (C3), C-reactive protein (CRP). Eight individuals aged 21.2 ± 3.2 years were the test subjects in the investigation. Protein studies showed a noticeable increase in the mean plasma levels of all APPs measured in experiment thus producing the evidence of the activation of acute phase response mechanisms while individual patterns revealed variability during the immersion period. The overall trends were similar to these in the previous immersion series. The augment in the strength of signal in stimulated light emission tests was higher after 1- and 2-day of immersion exposure than before the

  7. Catalytically active telomerase holoenzyme is assembled in the dense fibrillar component of the nucleolus during S phase.

    Science.gov (United States)

    Lee, Ji Hoon; Lee, Yang Sin; Jeong, Sun Ah; Khadka, Prabhat; Roth, Jürgen; Chung, In Kwon

    2014-02-01

    The maintenance of human telomeres requires the ribonucleoprotein enzyme telomerase, which is composed of telomerase reverse transcriptase (TERT), telomerase RNA component, and several additional proteins for assembly and activity. Telomere elongation by telomerase in human cancer cells involves multiple steps including telomerase RNA biogenesis, holoenzyme assembly, intranuclear trafficking, and telomerase recruitment to telomeres. Although telomerase has been shown to accumulate in Cajal bodies for association with telomeric chromatin, it is unclear where and how the assembly and trafficking of catalytically active telomerase is regulated in the context of nuclear architecture. Here, we show that the catalytically active holoenzyme is initially assembled in the dense fibrillar component of the nucleolus during S phase. The telomerase RNP is retained in nucleoli through the interaction of hTERT with nucleolin, a major nucleolar phosphoprotein. Upon association with TCAB1 in S phase, the telomerase RNP is transported from nucleoli to Cajal bodies, suggesting that TCAB1 acts as an S-phase-specific holoenzyme component. Furthermore, depletion of TCAB1 caused an increase in the amount of telomerase RNP associated with nucleolin. These results suggest that the TCAB1-dependent trafficking of telomerase to Cajal bodies occurs in a step separate from the holoenzyme assembly in nucleoli. Thus, we propose that the dense fibrillar component is the provider of active telomerase RNP for supporting the continued proliferation of cancer and stem cells.

  8. Orofacial muscular activity and related skin movement during the preparatory and sustained phases of tone production on the French horn.

    Science.gov (United States)

    Hirano, Takeshi; Kudo, Kazutoshi; Ohtsuki, Tatsuyuki; Kinoshita, Hiroshi

    2013-07-01

    This study investigated activity of the embouchure-related orofacial muscles during pre- and postattack phases of sound production by 10 trained French-horn players. Surface electromyogram (EMG) from five selected facial muscles, and related facial skin kinematics were examined in relation to pitch and intensity of a tone produced. No difference in EMGs and facial kinematics between the two phases was found, indicating importance of appropriate formation of preattack embouchure. EMGs in all muscles during the postattack phase increased linearly with an increase in pitch, and they also increased with tone intensity without interacting with the pitch effect. Orofacial skin movement remained constant across all pitches and intensities except for lateral retraction of the lips during high-pitch tone production. Contraction of the orofacial muscles is fundamentally isometric by which tension on the lips and the cheeks is regulated for flexible sound parameter control.

  9. Hydrophobic catalysts for liquid phase catalytic exchange: a review of preparation methods and influencing factors of catalytic activities

    International Nuclear Information System (INIS)

    Liquid phase catalytic exchange (LPCE) between liquid water and gaseous hydro- gen has been developed for various applications, such as tritium recovery, water upgrade and heavy-water production. Good wetproofing properties of the hydrophobic catalysts can make the reaction to proceed smoothly. In this article, the preparation methods of the hydrophobic catalysts and the factors affecting the catalytic activities are reviewed. In particular, progress on the hydrophobic Pt/C/inert carrier catalysts is introduced, including the selection of inert carrier and active metal carrier, and the preparation methods of carbon- supported Pt based catalysts. Basic research activities on controllable fabrication of hydro- phobic catalysts are discussed, including the LPCE reaction mechanism, and the relation between the microstructure of active metal and the catalytic activity, etc. Finally, questions remaining to be answered and future directions in the field of hydrophobic catalysts are discussed. (authors)

  10. Phase Preference by Active, Acetate-Utilizing Bacteria at the Rifle, CO Integrated Field Research Challenge Site

    Energy Technology Data Exchange (ETDEWEB)

    Kerkhof, L.; Williams, K.H.; Long, P.E.; McGuinness, L.

    2011-02-21

    Previous experiments at the Rifle, Colorado Integrated Field Research Challenge (IFRC) site demonstrated that field-scale addition of acetate to groundwater reduced the ambient soluble uranium concentration. In this report, sediment samples collected before and after acetate field addition were used to assess the active microbes via {sup 13}C acetate stable isotope probing on 3 phases [coarse sand, fines (8-approximately 150 {micro}m), groundwater (0.2-8 {micro}m)] over a 24-day time frame. TRFLP results generally indicated a stronger signal in {sup 13}C-DNA in the 'fines' fraction compared to the sand and groundwater. Before the field-scale acetate addition, a Geobacter-like group primarily synthesized {sup 13}C-DNA in the groundwater phase, an alpha Proteobacterium primarily grew on the fines/sands, and an Acinetobacter sp. and Decholoromonas-like OTU utilized much of the {sup 13}C acetate in both groundwater and particle-associated phases. At the termination of the field-scale acetate addition, the Geobacter-like species was active on the solid phases rather than the groundwater, while the other bacterial groups had very reduced newly synthesized DNA signal. These findings will help to delineate the acetate utilization patterns of bacteria in the field and can lead to improved methods for stimulating distinct microbial populations in situ.

  11. Help guides for post-accident consequence management: farm activities and exiting the emergency phase

    International Nuclear Information System (INIS)

    After having recalled the main actions foreseen in the PPIs (plans particuliers d'intervention, intervention specific plans) in case of radionuclide release in the environment after a nuclear accident, i.e. sheltering and ingestion of steady iodine, and also indicated the different phases of consequence management (preparation, emergency and post-accident phases), this report describes and comments the contents of two guides published by the IRSN (the French Radioprotection and Nuclear Safety Institute) and dealing with the management of post-accident consequences. The first one is a guide to aid to decision-making for the management of the agricultural sector in case of nuclear accident, and the second one is a guide for the preparation of the end of the emergency phase in which actions to be performed during the first week after the end of accidental releases are described

  12. Protein C activation during the initial phase of experimental acute pancreatitis in the rabbit

    DEFF Research Database (Denmark)

    Ottesen, L H; Bladbjerg, E-M; Osman, M;

    2000-01-01

    activity), anticoagulant proteins (protein C, antithrombin) and fibrinolytic factors (tissue plasminogen activator, plasminogen activator inhibitor-1) were performed for 5 h. RESULTS: ANP was confirmed by elevated serum amylase, development of ascites, and histological changes of the pancreas. A moderate...... of the lungs or kidneys was found in 2 rabbits with ANP. CONCLUSION: An immediate activation of protein C is a specific characteristic of the haemostatic activation in ANP in rabbits. This activation has not been described previously and the possible therapeutic implications ought to be studied....

  13. Mechanical stress induced activity and phase composition changes in sulfated zirconia catalysts

    OpenAIRE

    Klose, B; Jentoft, R.; Hahn, A.; T. Ressler; Kröhnert, J.; Wrabetz, S.; X. Yang; Jentoft, F.

    2003-01-01

    Sulfated zirconia and Mn-promoted sulfated zirconia (0.5 and 2.0 wt% Mn) catalysts were subjected to mechanical stress. Pressing (10 min 540 MPa), milling (10 min vibrating mill), and grinding (manually, 10 min agate mortar) effected a partial phase transformation from the tetragonal to the monoclinic phase of ZrO2. The mechanical stress also reduced the n-butane isomerization rate (1 kPa n-butane, 323-378K, atmospheric pressure) to 30% and less of that measured for untreated catalyst. Standa...

  14. Phase dynamics of nearly stationary patterns in activator-inhibitor systems

    Energy Technology Data Exchange (ETDEWEB)

    Hagberg, Aric [Center for Nonlinear Studies and T-7, Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Meron, Ehud [The Jacob Blaustein Institute for Desert Research and the Physics Department, Ben-Gurion University, Sede Boker Campus 84990, (Israel); Passot, Thierry [Observatoire de la Cote d' Azur, Boite Postale 4229, 06304 Nice Cedex 4, (France); Department of Mathematics, University of Arizona, Tucson, Arizona 85721 (United States)

    2000-06-01

    The slow dynamics of nearly stationary patterns in a FitzHugh-Nagumo model are studied using a phase dynamics approach. A Cross-Newell phase equation describing slow and weak modulations of periodic stationary solutions is derived. The derivation applies to the bistable, excitable, and Turing unstable regimes. In the bistable case stability thresholds are obtained for the Eckhaus and zigzag instabilities and for the transition to traveling waves. Neutral stability curves demonstrate the destabilization of stationary planar patterns at low wave numbers to zigzag and traveling modes. Numerical solutions of the model system support the theoretical findings. (c) 2000 The American Physical Society.

  15. Sensitivity analysis of an LCL-filter-based three-phase active rectifier via a virtual circuit approach

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Chiarantoni, Ernesto; Aquila, Antonio Dell’;

    2004-01-01

    , to the grid side stiffness and to the parameters of the controller has never been detailed considered. In this paper the experimental results of an LCL-filter-based three-phase active rectifier are analysed with the circuit theory approach. A ?virtual circuit? is synthesized in role of the digital controller...... and of the feedback filters to have an homogenous model that allows a sensitivity analysis which is rigorous and straightforward for the industry....

  16. An Overview of Mode of Action and Analytical Methods for Evaluation of Gas Phase Activities of Flame Retardants

    OpenAIRE

    Khalifah A. Salmeia; Julien Fage; Shuyu Liang; Sabyasachi Gaan

    2015-01-01

    The latest techniques used to prove, describe and analyze the gas phase activity of a fire retardant used in polymeric materials are briefly reviewed. Classical techniques, such as thermogravimetric analysis or microscale combustion calorimetry, as well as complex and advanced analytical techniques, such as modified microscale combustion calorimeter (MCC), molecular beam mass spectroscopy and vacuum ultra violet (VUV) photoionization spectroscopy coupled with time of flight MS (TOF-MS), are d...

  17. The value of telerehabilitation in encouraging coronary artery disease patients to stay active after the acute rehabilitation phase

    OpenAIRE

    Frederix, Ines; Hansen, Dominique; Bonne, K.; Alders, Toon; Van Driessche, Niels; Berger, Jan; DENDALE, PAUL

    2012-01-01

    Purpose. The aim of this study was to evaluate whether the addition of a motion sensor with automated feed-back by SMS to the conventional rehabilitation program could result in an increase in daily activity among coronary artery disease patients. Methods. 20 coronary artery disease patients were included in this randomised, controlled trial after admission for PCI or CABG (target population of the study n = 80). All patients were included during phase II of the cardiac rehabilitation pro...

  18. Increased Serum Phospholipase A2 Activity in Advanced Chronic Liver Disease as an Expression of the Acute Phase Response

    OpenAIRE

    Mario Pirisi; Carlo Fabris; Maria Piera Panozzo; Giorgio Soardo; Pierluigi Toniutto; Ettore Bartou

    1993-01-01

    Phospholipase A2 (PLA2) modifications were investigated in patients with acute and chronic liver diseases, PLA2 variations were related to indices of liver function as well as to parameters of the acute phase response. Serum PLA2 activity modifications were f1uorimetrically measured in 105 patients affected by acute and chronic liver diseases or extra-hepatic diseases. One-way ANOV A demonstrated a significant difference among groups (F= 4.53, P

  19. Phase Resetting Light Pulses Induce Per1 and Persistent Spike Activity in a Subpopulation of Biological Clock Neurons

    Science.gov (United States)

    Kuhlman, Sandra J.; Silver, Rae; Le Sauter, Joseph; Bult-Ito, Abel; McMahon, Douglas G.

    2012-01-01

    The endogenous circadian clock of the mammalian suprachiasmatic nucleus (SCN) can be reset by light to synchronize the biological clock of the brain with the external environment. This process involves induction of immediate-early genes such as the circadian clock gene Period1 (Per1) and results in a stable shift in the timing of behavioral and physiological rhythms on subsequent days. The mechanisms by which gene activation permanently alters the phase of clock neuron activity are unknown. To study the relationship between acute gene activation and persistent changes in the neurophysiology of SCN neurons, we recorded from SCN neurons marked with a dynamic green fluorescent protein (GFP) reporter of Per1 gene activity. Phase-resetting light pulses resulted in Per1 induction in a distinct subset of SCN neurons that also exhibited a persistent increase in action potential frequency 3–5 hr after a light pulse. By simultaneously quantifying Per1 gene activation and spike frequency in individual neurons, we found that the degree of Per1 induction was highly correlated with neuronal spike frequency on a cell-by-cell basis. Increased neuronal activity was mediated by membrane potential depolarization as a result of a reduction in outward potassium current. Double-label immunocytochemistry revealed that vasoactive intestinal peptide (VIP)-expressing cells, but not arginine vasopressin (AVP)-expressing cells, exhibited significant Per1 induction by light pulses. Rhythmic GFP expression occurred in both VIP and AVP neurons. Our results indicate that the steps that link acute molecular events to permanent changes in clock phase involve persistent suppression of potassium current, downstream of Per1 gene induction, in a specific subset of Per1-expressing neurons enriched for VIP. PMID:12598633

  20. The Influence of Weather and Lunar Phases on the Flight Activity of Paederus Rove Beetles (Coleoptera: Staphylinidae).

    Science.gov (United States)

    Silva, F S; Lobo, S E P D; Lima, D C B; Brito, J M; Costa-Neta, B M

    2015-06-01

    Despite the medical importance of Paederus beetles, no studies have studied the influence of the abiotic factors on the flight activity and nighttime dispersal of these insects in Brazil. Therefore, the influence of both climatic factors and moon phase on black-light catches of Paederus rove beetles was investigated. Paederus beetles were attracted to a black light source hourly from 1800 to 0600 hours, and data on weather conditions as well as moon phase data were taken for every sampling date. Overall, 543 individuals of Paederus beetles belonging to four species were captured: P. protensus, P. columbinus, P. brasiliensis, and P. mutans. Paederus beetles were mostly active in the warmest parts of the studied nights. Variations in nighttime temperature, relative humidity, wind speed, cloud cover, and moon phases appear not to affect Paederus flight. The diurnal temperature was observed to affect the night hourly dispersal of Paederus rove beetles as well as their distribution pattern during the entire period of study. The true environmental condition responsible for Paederus beetles seasonal pattern and daily night dispersal in northeastern Brazil were the annual moisture and drought cycles and the diurnal maximum temperatures, respectively. Significant trap catches were observed in the earliest hours after sunset (1800-2100), and people must be aware of this fact, as it can notably increase the risk of acquiring linearis dermatitis from the contact with large numbers of active Paederus.

  1. Gp130-dependent release of acute phase proteins is linked to the activation of innate immune signaling pathways.

    Directory of Open Access Journals (Sweden)

    Maren Luchtefeld

    Full Text Available BACKGROUND: Elevated levels of acute phase proteins (APP are often found in patients with cardiovascular diseases. In a previous study, we demonstrated the importance of the IL-6-gp130 axis -as a key regulator of inflammatory acute phase signaling in hepatocytes-for the development of atherosclerosis. BACKGROUND/PRINCIPAL FINDINGS: Gp130-dependent gene expression was analyzed in a previously established hepatocyte-specific gp130 knockout mouse model. We performed whole transcriptome analysis in isolated hepatocytes to measure tissue specific responses after proinflammatory stimulus with IL-6 across different time points. Our analyses revealed an unexpected small gene cluster that requires IL-6 stimulus for early activation. Several of the genes in this cluster are involved in different cell defense mechanisms. Thus, stressors that trigger both general stress and inflammatory responses lead to activation of a stereotypic innate cellular defense response. Furthermore, we identified a potential biomarker Lipocalin (LCN 2 for the gp130 dependent early inflammatory response. CONCLUSIONS/SIGNIFICANCE: Our findings suggest a complex network of tightly linked genes involved in the early activation of different parts of the innate immune response including acute phase proteins, complement and coagulation cascade.

  2. Systematic Design of the Lead-Lag Network Method for Active Damping in LCL-Filter Based Three Phase Converters

    DEFF Research Database (Denmark)

    Alzola, Rafael Pena; Liserre, Marco; Blaabjerg, Frede;

    2014-01-01

    Three-phase active rectifiers guarantee sinusoidal input currents and unity power factor at the price of a high switching frequency ripple. To adopt an LCL-filter, instead of an L-filter, allows using reduced values for the inductances and so preserving dynamics. However, stability problems can...... arise in the current control loop if the present resonance is not properly damped. Passive damping simply adds resistors in series with the LCL-filter capacitors. This simplicity is at the expense of increased losses and encumbrances. Active damping modifies the control algorithm to attain stability...

  3. Benchmark of AC and DC Active Power Decoupling Circuits for Second-Order Harmonic Mitigation in Kilowatt-Scale Single-Phase Inverters

    DEFF Research Database (Denmark)

    Qin, Zian; Tang, Yi; Loh, Poh Chiang;

    2016-01-01

    This paper presents the benchmark study of ac and dc active power decoupling circuits for second order harmonic mitigation in kW scale single-phase inverters. First of all, a brief comparison of recently reported active power decoupling circuits is given, and the best solution that can achieve high...... results obtained on a 2 kW single-phase inverter....

  4. New origin firing is inhibited by APC/CCdh1 activation in S-phase after severe replication stress.

    Science.gov (United States)

    Ercilla, Amaia; Llopis, Alba; Feu, Sonia; Aranda, Sergi; Ernfors, Patrik; Freire, Raimundo; Agell, Neus

    2016-06-01

    Defects in DNA replication and repair are known to promote genomic instability, a hallmark of cancer cells. Thus, eukaryotic cells have developed complex mechanisms to ensure accurate duplication of their genomes. While DNA damage response has been extensively studied in tumour cells, the pathways implicated in the response to replication stress are less well understood especially in non-transformed cells. Here we show that in non-transformed cells, APC/C(Cdh1) is activated upon severe replication stress. Activation of APC/C(Cdh1) prevents new origin firing and induces permanent arrest in S-phase. Moreover, Rad51-mediated homologous recombination is also impaired under these conditions. APC/C(Cdh1) activation in S-phase occurs after replication forks have been processed into double strand breaks. Remarkably, this activation, which correlates with decreased Emi1 levels, is not prevented by ATR/ATM inhibition, but it is abrogated in cells depleted of p53 or p21. Importantly, we found that the lack of APC/C(Cdh1) activity correlated with an increase in genomic instability. Taken together, our results define a new APC/C(Cdh1) function that prevents cell cycle resumption after prolonged replication stress by inhibiting origin firing, which may act as an additional mechanism in safeguarding genome integrity.

  5. Identification of Active Phase for Selective Oxidation of Benzyl Alcohol with Molecular Oxygen Catalyzed by Copper-Manganese Oxide Nanoparticles

    Directory of Open Access Journals (Sweden)

    Roushown Ali

    2013-01-01

    Full Text Available Catalytic activity of copper-manganese mixed oxide nanoparticles (Cu/Mn = 1 : 2 prepared by coprecipitation method has been studied for selective oxidation of benzyl alcohol using molecular oxygen as an oxidizing agent. The copper-manganese (CuMn2 oxide catalyst exhibited high specific activity of 15.04 mmolg−1 h−1 in oxidation of benzyl alcohol in toluene as solvent. A 100% conversion of the benzyl alcohol was achieved with >99% selectivity to benzaldehyde within a short reaction period at 102°C. It was found that the catalytic performance is dependent on calcination temperature, and best activity was obtained for the catalyst calcined at 300°C. The high catalytic performance of the catalyst can be attributed to the formation of active MnO2 phase or absence of less active Mn2O3 phase in the mixed CuMn2 oxide. The catalyst has been characterized by powder X-ray diffraction (XRD, thermogravimetric analysis (TGA, scanning electron microscopy (SEM, transmission electron microscopy (TEM, Brunauer Emmett-Teller (BET surface area measurement, and Fourier transform infrared (FT-IR spectroscopies.

  6. Lunar phase function at 1064 nm from Lunar Orbiter Laser Altimeter passive and active radiometry

    Science.gov (United States)

    Barker, M. K.; Sun, X.; Mazarico, E.; Neumann, G. A.; Zuber, M. T.; Smith, D. E.

    2016-07-01

    We present initial calibration and results of passive radiometry collected by the Lunar Orbiter Laser Altimeter onboard the Lunar Reconnaissance Orbiter over the course of 12 months. After correcting for time- and temperature-dependent dark noise and detector responsivity variations, the LOLA passive radiometry measurements are brought onto the absolute radiance scale of the SELENE Spectral Profiler. The resulting photometric precision is estimated to be ∼5%. We leverage the unique ability of LOLA to measure normal albedo to explore the 1064 nm phase function's dependence on various geologic parameters. On a global scale, we find that iron abundance and optical maturity (quantified by FeO and OMAT) are the dominant controlling parameters. Titanium abundance (TiO2), surface roughness on decimeter to decameter scales, and soil thermophysical properties have a smaller effect, but the latter two are correlated with OMAT, indicating that exposure age is the driving force behind their effects in a globally-averaged sense. The phase function also exhibits a dependence on surface slope at ∼300 m baselines, possibly the result of mass wasting exposing immature material and/or less space weathering due to reduced sky visibility. Modeling the photometric function in the Hapke framework, we find that, relative to the highlands, the maria exhibit decreased backscattering, a smaller opposition effect (OE) width, and a smaller OE amplitude. Immature highlands regolith has a higher backscattering fraction and a larger OE width compared to mature highlands regolith. Within the maria, the backscattering fraction and OE width show little dependence on TiO2 and OMAT. Variations in the phase function shape at large phase angles are observed in and around the Copernican-aged Jackson crater, including its dark halo, a putative impact melt deposit. Finally, the phase function of the Reiner Gamma Formation behaves more optically immature than is typical for its composition and OMAT

  7. Activated carbon derived from peat soil as a framework for the preparation of shape-stabilized phase change material

    International Nuclear Information System (INIS)

    This work focuses on the preparation of AC (activated carbon) through a physical activation method using peat soil as a precursor, followed by the use of the AC as an inorganic framework for the preparation of SPCM (shape-stabilized phase change material). The SPCM, composed of n-octadecane as the core and AC pores as a framework, was fabricated by a simple impregnation method, with the mass fraction of n-octadecane varying from 10 to 90 wt.%. The AC has a specific surface area of 893 m2 g−1 and an average pore size of 22 Å. The field emission scanning electron microscope images and nitrogen gas adsorption-desorption isotherms shows that the n-octadecane was actually encapsulated into the AC pores. The melting and freezing temperatures of the composite PCM (phase change material) were 30.9 °C and 24.1 °C, respectively, and its corresponding latent heat values were 95.4 Jg−1 and 99.6 Jg−1, respectively. The composite shows a good thermal reliability, even after 1000 melting/freezing cycles. The present research provided a new SPCM material for thermal energy storage as well as some new insights into the design of composite PCM by tailoring the pore structure of AC derived from peat soil, a natural resource. - Highlights: • Activated carbon from peat soil was used as framework. • n-Octadecane/activated carbon composite was fabricated by impregnation method. • The thermal property could be tailor by adjusting pore size of activated carbon. • The shape-stabilized PCM (phase change material) have the potential to be used for thermal energy storage

  8. Chemical Stockpile Disposal Program: Review and comment on the Phase 1 environmental report for the Pueblo Depot Activity, Pueblo, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Olshansky, S.J.; Krummel, J.R.; Policastro, A.J.; McGinnis, L.D.

    1994-03-01

    As part of the Chemical Stockpile Disposal Program, an independent review is presented of the US Army Phase I environmental report for the disposal of chemical agents and munitions stored at the Pueblo Depot Activity (PUDA) in Pueblo, Colorado. The Phase I report addresses new and additional concerns not incorporated in the final programmatic environmental impact statement (FPEIS). These concerns are addressed by examining site-specific data for the PUDA. On the basis of our review of the Phase I report, we concluded that on-site meteorological data from December 1988 to June 1992 appear to be of insufficient quality to have been used instead of the off-site Pueblo airport data. No additional meteorological data have been collected since June 1992. The Phase I report briefly mentions problems with the air pollution control system. These problems will likely require the systems to be upgraded at the Johnston Atoll site and at each of the other depots in the continental United States. Without such improvements, the probability of accidents during start-up and shutdown would likely increase. The Army has a lessons-learned program to incorporate improvements into the design of future facilities. The Phase I report does not make any design change commitments. These issues need to be fully evaluated and resolved before any final conclusion concerning the adequacy of the decision in the FPEIS can be made with respect to the PUDA. With the exception of this issue, the inclusion of other more detailed site-specific data in the Phase I report does not change the decision reached in the FPEIS (which favored on-site disposal at the PUDA). We recommend that site-specific data on water, ecological, socioeconomic, and cultural resources and emergency planning and preparedness be considered explicitly in the site-specific EIS decision-making process.

  9. Chemical Stockpile Disposal Program: Review and comment on the Phase 1 environmental report for the Pueblo Depot Activity, Pueblo, Colorado

    International Nuclear Information System (INIS)

    As part of the Chemical Stockpile Disposal Program, an independent review is presented of the US Army Phase I environmental report for the disposal of chemical agents and munitions stored at the Pueblo Depot Activity (PUDA) in Pueblo, Colorado. The Phase I report addresses new and additional concerns not incorporated in the final programmatic environmental impact statement (FPEIS). These concerns are addressed by examining site-specific data for the PUDA. On the basis of our review of the Phase I report, we concluded that on-site meteorological data from December 1988 to June 1992 appear to be of insufficient quality to have been used instead of the off-site Pueblo airport data. No additional meteorological data have been collected since June 1992. The Phase I report briefly mentions problems with the air pollution control system. These problems will likely require the systems to be upgraded at the Johnston Atoll site and at each of the other depots in the continental United States. Without such improvements, the probability of accidents during start-up and shutdown would likely increase. The Army has a lessons-learned program to incorporate improvements into the design of future facilities. The Phase I report does not make any design change commitments. These issues need to be fully evaluated and resolved before any final conclusion concerning the adequacy of the decision in the FPEIS can be made with respect to the PUDA. With the exception of this issue, the inclusion of other more detailed site-specific data in the Phase I report does not change the decision reached in the FPEIS (which favored on-site disposal at the PUDA). We recommend that site-specific data on water, ecological, socioeconomic, and cultural resources and emergency planning and preparedness be considered explicitly in the site-specific EIS decision-making process

  10. DQ reference frame modeling and control of single-phase active power decoupling circuits

    DEFF Research Database (Denmark)

    Tang, Yi; Qin, Zian; Blaabjerg, Frede;

    2015-01-01

    Power decoupling circuits can compensate the inherent double line frequency ripple power in single-phase systems and greatly facilitate their dc-link capacitor design. Example applications of power decoupling circuit include photovoltaic, light-emitting diode, fuel cell, and motor drive systems....... This paper presents the dq synchronous reference frame modeling of single-phase power decoupling circuits and a complete model describing the dynamics of dc-link ripple voltage is presented. The proposed model is universal and valid for both inductive and capacitive decoupling circuits, and the input...... of decoupling circuits can be either dependent or independent of its front-end converters. Based on this model, a dq synchronous reference frame controller is designed which allows the decoupling circuit to operate in two different modes because of the circuit symmetry. Simulation and experimental results...

  11. Secretory activity and cell cycle alteration of alveolar type II cells in the early and late phase after irradiation

    International Nuclear Information System (INIS)

    Purpose: Type II cells and the surfactant system have been proposed to play a central role in pathogenesis of radiation pneumonitis. We analyzed the secretory function and proliferation parameters of alveolar type II cells in the early (until 24 h) and late phase (1-5 weeks) after irradiation (RT) in vitro and in vivo. Methods and Materials: Type II cells were isolated from rats according to the method of Dobbs. Stimulation of secretion was induced with terbutaline, adenosine triphosphate (ATP), and 12-O-tetradecanoylphorbol-13-acetate (TPA) for a 2-h period. Determination of secretion was performed using 3H-labeled phosphatidylcholine. For the early-phase analysis, freshly isolated and adherent type II cells were irradiated in vitro with 9-21 Gy (stepwise increase of 3 Gy). Secretion stimulation was initiated 1, 6, 24, and 48 h after RT. For late-phase analysis, type II cells were isolated 1-5 weeks after 18 Gy whole lung or sham RT. Each experiment was repeated at least fivefold. Flow cytometry was used to determine cell cycle distribution and proliferating cell nuclear antigen index. Results: During the early-phase (in vitro) analysis, we found a normal stimulation of surfactant secretion in irradiated, as well as unirradiated, cells. No change in basal secretion and no dose effect were seen. During the late phase, 1-5 weeks after whole lung RT, we observed enhanced secretory activity for all secretagogues and a small increase in basal secretion in Weeks 3 and 4 (pneumonitis phase) compared with controls. The total number of isolated type II cells, as well as the rate of viable cells, decreased after the second post-RT week. Cell cycle alterations suggesting an irreversible G2/M block occurred in the second post-RT week and did not resolve during the observation period. The proliferating cell nuclear antigen index of type II cells from irradiated rats did not differ from that of controls. Conclusion: In contrast to literature data, we observed no direct effect

  12. STAT3 activation in skeletal muscle links muscle wasting and the acute phase response in cancer cachexia.

    Directory of Open Access Journals (Sweden)

    Andrea Bonetto

    Full Text Available BACKGROUND: Cachexia, or weight loss despite adequate nutrition, significantly impairs quality of life and response to therapy in cancer patients. In cancer patients, skeletal muscle wasting, weight loss and mortality are all positively associated with increased serum cytokines, particularly Interleukin-6 (IL-6, and the presence of the acute phase response. Acute phase proteins, including fibrinogen and serum amyloid A (SAA are synthesized by hepatocytes in response to IL-6 as part of the innate immune response. To gain insight into the relationships among these observations, we studied mice with moderate and severe Colon-26 (C26-carcinoma cachexia. METHODOLOGY/PRINCIPAL FINDINGS: Moderate and severe C26 cachexia was associated with high serum IL-6 and IL-6 family cytokines and highly similar patterns of skeletal muscle gene expression. The top canonical pathways up-regulated in both were the complement/coagulation cascade, proteasome, MAPK signaling, and the IL-6 and STAT3 pathways. Cachexia was associated with increased muscle pY705-STAT3 and increased STAT3 localization in myonuclei. STAT3 target genes, including SOCS3 mRNA and acute phase response proteins, were highly induced in cachectic muscle. IL-6 treatment and STAT3 activation both also induced fibrinogen in cultured C2C12 myotubes. Quantitation of muscle versus liver fibrinogen and SAA protein levels indicates that muscle contributes a large fraction of serum acute phase proteins in cancer. CONCLUSIONS/SIGNIFICANCE: These results suggest that the STAT3 transcriptome is a major mechanism for wasting in cancer. Through IL-6/STAT3 activation, skeletal muscle is induced to synthesize acute phase proteins, thus establishing a molecular link between the observations of high IL-6, increased acute phase response proteins and muscle wasting in cancer. These results suggest a mechanism by which STAT3 might causally influence muscle wasting by altering the profile of genes expressed and

  13. Overcoming Junior High School Students' Misconceptions About Microscopic Views of Phase Change: A Study of an Analogy Activity

    Science.gov (United States)

    Tsai, Chin-Chung

    1999-03-01

    This study was conducted to examine the effectiveness of an analogy activity, which was designed to overcome junior high students' misconceptions about the microscopic views of phase change. Eighty Taiwanese 8 th graders were randomly assigned to either a control group or an experimental group. For the control group, the subjects were instructed through traditional teaching whereas for the experimental group, an analogy activity was conducted on students. This specific analogy activity was presented in the form of role-playing in which students acted as particles and worked together to perform the conditions of phase changes. Through analyzing these students' drawings of the atom arrangements for the three states of some substances, it was found that the students of experimental group, though in many cases, did not perform statistically better than did those of control group in an immediate posttest. The comparisons of a delay test between these two groups indicated that the analogy activity had clearly positive impacts on students' conceptual change on these scientific concepts in terms of long-term observations.

  14. Adoption of community-based cardiac rehabilitation programs and physical activity following phase III cardiac rehabilitation in Scotland: a prospective and predictive study.

    Science.gov (United States)

    Sniehotta, Falko F; Gorski, Charlotta; Araujo-Soares, Vera

    2010-09-01

    Little is known about levels of physical activity and attendance at phase IV community-based Cardiac Rehabilitation (CR) programs following completion of exercise-focussed, hospital-based phase III CR. This study aims to test, compare and combine the predictive utility of the Common-Sense Self-Regulation Model (CS-SRM) and the extended Theory of Planned Behaviour (TPB) with action planning for two rehabilitation behaviours: physical activity and phase IV CR attendance. Individuals diagnosed with coronary heart disease (n = 103) completed baseline measures of illness perceptions, intentions, perceived behavioural control (PBC), action planning and past physical activity in the last week of a phase III CR program, and 95 participants completed follow-up measures of physical activity and attended phase IV CR (objectively confirmed) 2 months later. Only one predictor (PBC/cyclical timeline) significantly predicted levels and change of physical activity. While illness perceptions were not predictive of phase IV CR attendance, the extended TPB model showed good predictive power with action planning and intention as the most powerful predictors. Amongst participants who planned when and where to attend phase IV CR at the end of phase III rehabilitation, 65.9% subsequently attended a phase IV CR program compared to only 18.5% of those who had not made a plan. This study adds to our understanding of cardiac rehabilitation behaviour after completion of health service delivered programs. Comparing theoretical models and rehabilitation behaviours contributes to the development of behaviour theory.

  15. Linear free energy relationships between aqueous phase hydroxyl radical reaction rate constants and free energy of activation.

    Science.gov (United States)

    Minakata, Daisuke; Crittenden, John

    2011-04-15

    The hydroxyl radical (HO(•)) is a strong oxidant that reacts with electron-rich sites on organic compounds and initiates complex radical chain reactions in aqueous phase advanced oxidation processes (AOPs). Computer based kinetic modeling requires a reaction pathway generator and predictions of associated reaction rate constants. Previously, we reported a reaction pathway generator that can enumerate the most important elementary reactions for aliphatic compounds. For the reaction rate constant predictor, we develop linear free energy relationships (LFERs) between aqueous phase literature-reported HO(•) reaction rate constants and theoretically calculated free energies of activation for H-atom abstraction from a C-H bond and HO(•) addition to alkenes. The theoretical method uses ab initio quantum mechanical calculations, Gaussian 1-3, for gas phase reactions and a solvation method, COSMO-RS theory, to estimate the impact of water. Theoretically calculated free energies of activation are found to be within approximately ±3 kcal/mol of experimental values. Considering errors that arise from quantum mechanical calculations and experiments, this should be within the acceptable errors. The established LFERs are used to predict the HO(•) reaction rate constants within a factor of 5 from the experimental values. This approach may be applied to other reaction mechanisms to establish a library of rate constant predictions for kinetic modeling of AOPs. PMID:21410278

  16. Cyclin E-induced S phase without activation of the pRb/E2F pathway

    DEFF Research Database (Denmark)

    Lukas, J; Herzinger, T; Hansen, Klaus;

    1997-01-01

    In cells of higher eukaryotes, cyclin D-dependent kinases Cdk4 and Cdk6 and, possibly, cyclin E-dependent Cdk2 positively regulate the G1- to S-phase transition, by phosphorylating the retinoblastoma protein (pRb), thereby releasing E2F transcription factors that control S-phase genes. Here we...... of cyclin E, but not cyclin D1, can override G1 arrest imposed by either the p16INK4a Cdk inhibitor specific for Cdk4 and Cdk6 or a novel phosphorylation-deficient mutant pRb. Several complementary approaches to assess E2F activation, including quantitative reporter assays in live cells, showed...... for a cyclin E-controlled S phase-promoting event in somatic cells downstream of or parallel to phosphorylation of pRb and independent of E2F activation. They furthermore indicate that a lack of E2F-mediated transactivation can be compensated by hyperactivation of this cyclin E-controlled event....

  17. A Fast Series Active Filter using Sliding Mode Control to Correct and Regulate Unbalance Voltage in Three-Phase System

    Directory of Open Access Journals (Sweden)

    Theerayuth Chatchanayuenyong

    2009-01-01

    Full Text Available Problem statement: A Sliding Mode Controller (SMC with fast reference voltage generation to correct and regulate unbalance voltage in three-phase system was proposed. Approach: The compensation algorithm was not based on three-symmetrical component decomposition so the controller can yield a fast response that was essential in such a critical real time control work. The reference voltages were fed to the SMC, which was a robust closed loop controller. Results: The proposed algorithm and control scheme of series active filter could correct and regulate unbalance voltage in three-phase system under arbitrary fault conditions of the utility supply. Conclusion: A design example and its simulation results proved the concept and validated the proposed algorithm.

  18. Active galactic nuclei flicker: an observational estimate of the duration of black hole growth phases of ~1e5 years

    CERN Document Server

    Schawinski, Kevin; Berney, Simon; Sartori, Lia

    2015-01-01

    We present an observational constraint for the typical active galactic nucleus (AGN) phase lifetime. The argument is based on the time lag between an AGN central engine switching on and becoming visible in X-rays, and the time the AGN then requires to photoionize a large fraction of the host galaxy. Based on the typical light travel time across massive galaxies, and the observed fraction of X-ray selected AGN without AGN-photoionized narrow lines, we estimate that the AGN phase typically lasts $\\sim10^{5}$ years. This lifetime is short compared to the total growth time of $10^{7}-10^{9}$ years estimated from e.g. the Soltan argument and implies that black holes grow via many such short bursts and that AGN therefore "flicker" on and off. We discuss some consequences of this flickering behavior for AGN feedback and the analogy of X-ray binaries and AGN lifecycles.

  19. Active phase double crystal monochromator for JET (diagnostic system KS1)

    International Nuclear Information System (INIS)

    The determination of the impurity concentrations in JET plasmas by absolute radiation measurements in a wide spectral range can be done with a double crystal monochromator device in parallel mode, which is able to operate during all experimental phases of JET. The report describes the engineering design and tests for a double crystal monochromator that fulfills the conditions of parallel orientation of the two crystals during fast wavelength scan, of shielding against neutrons and gamma rays by its folded optical pathway and of sufficient spectral resolution for line profile measurements. (orig.)

  20. Invasion-wave induced first-order phase transition in systems of active particles

    CERN Document Server

    Ihle, Thomas

    2013-01-01

    An Enskog-like kinetic equation for self-propelled particles is solved numerically. I study a density instability near the transition to collective motion and find that while hydrodynamics breaks down, the kinetic approach leads to soliton-like supersonic waves with steep leading kinks and Knudsen numbers of order one. These waves show hysteresis, modify the transition threshold and lead to an abrupt jump of the global order parameter if the noise level is changed. Thus they provide a mechanism to change the second-order character of the phase transition to first order.

  1. Detecting stable phase structures in EEG signals to classify brain activity amplitude patterns

    Institute of Scientific and Technical Information of China (English)

    Yusely RUIZ; Guang LI; Walter J. FREEMAN; Eduardo GONZALEZ

    2009-01-01

    Obtaining an electrocorticograms (ECoG) signal requires an invasive procedure in which brain activity is recorded from the cortical surface. In contrast, obtaining electroencephalograms (EEG) recordings requires the non-invasive procedure of recording the brain activity from the scalp surface, which allows EEG recordings to be performed more easily on healthy humans. In this work, a technique previously used to study spatial-temporal patterns of brain activity on animal ECoG was adapted for use on EEG. The main issues are centered on solving the problems introduced by the increment on the interelectrode distance and the procedure to detect stable frames. The results showed that spatial patterns of beta and gamma activity can also be extracted from the EEG signal by using stable frames as time markers for feature extraction. This adapted technique makes it possible to take advantage of the cognitive and phenomenological awareness of a normal healthy subject.

  2. Power quality improvement using DPC controlled three-phase shunt active filter

    Energy Technology Data Exchange (ETDEWEB)

    Chaoui, Abdelmadjid [Laboratoire d' Automatique et d' Informatique Industrielle (LAII-ESIP), Universite de Poitiers (France); Gaubert, Jean-Paul; Krim, Fateh [Laboratoire d' Electronique de Puissance et Commande Industrielle (LEPCI), Universite de Setif (Algeria)

    2010-06-15

    This paper presents a new control method entitled direct power control (DPC) for shunt active power filter (APF), which is applied to eliminate line current harmonics and compensate reactive power. Its main goal is to rebuild active and reactive source powers to be compared to references values using hysteresis control. The active power reference is issue of DC-side of inverter and reactive power reference is set to zero for unity power factor. The outputs of hysteresis controllers associated with a switching table, control the instantaneous active and reactive power by selecting the optimum switching state of the voltage source inverter (VSI). A theoretical analysis with a complete simulation of the system and experimental results are presented to prove the excellent performance of the proposed technique. (author)

  3. Superior decoupled control of active and reactive power for three-phase voltage source converters

    OpenAIRE

    RAHBARIMAGHAM, HESAM; AMIRI, ERFAN MAALI; VAHIDI, Behrooz; GHAREHPETIAN, GEVORG BABAMALEK; Abedi, Mehrdad

    2015-01-01

    This paper presents an active-reactive power control strategy for voltage source converters (VSCs) based on derivation of the direct and quadrature components of the VSC output current. The proposed method utilizes a multivariable proportional-integral controller and provides almost completely decoupled control capability of the active and reactive power with almost full disturbance rejection due to step changes in the power exchanged between the VSC and the grid. It also imposes fast transie...

  4. Recovery Efficiency Test Project Phase 2 activity report, Volume 1. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Overbey, W.K. Jr.; Salamy, S.P.; Locke, C.D.

    1989-02-01

    The purpose of Phase II operations of the Recovery Efficiency Test Project is to enhance the natural production of the well and evaluate the relative improvement as a function of the type of stimulation conducted. Another purpose is to compare the stimulated production performance of the horizontal well with vertical wells in the field. The objectives considered for Phase II operations and plans were: (1) Develop a rationale for a systematic approach to designing stimulations for the well. (2) Conduct a series of stimulations designed to optimize the fluids, injection rates, proppant volumes and general approach to stimulating a horizontal well with similar geologic conditions. (3) Develop and test a method or methods for determining the geometry of stimulation-induced fractures. (4) Conduct tests and analyze the results to determine the efficiency of stimulation operations. The technical approach pursued in developing plans to accomplish three objectives was to: (1) Review the data needs for all objectives and obtain that data first. (2) Identify the operating geologic, geomechanical, and reservoir parameters that need additional clarification or definition. (3) Investigate existing models which could be used to plan or evaluate stimulation on the well and the reservoir. (4) Plan for analysis and verification of models and approaches.

  5. Self-organization via active exploration in robotic applications. Phase 2: Hybrid hardware prototype

    Science.gov (United States)

    Oegmen, Haluk

    1993-01-01

    In many environments human-like intelligent behavior is required from robots to assist and/or replace human operators. The purpose of these robots is to reduce human time and effort in various tasks. Thus the robot should be robust and as autonomous as possible in order to eliminate or to keep to a strict minimum its maintenance and external control. Such requirements lead to the following properties: fault tolerance, self organization, and intelligence. A good insight into implementing these properties in a robot can be gained by considering human behavior. In the first phase of this project, a neural network architecture was developed that captures some fundamental aspects of human categorization, habit, novelty, and reinforcement behavior. The model, called FRONTAL, is a 'cognitive unit' regulating the exploratory behavior of the robot. In the second phase of the project, FRONTAL was interfaced with an off-the-shelf robotic arm and a real-time vision system. The components of this robotic system, a review of FRONTAL, and simulation studies are presented in this report.

  6. Liquid phase deposition of WO3/TiO2 heterojunction films with high photoelectrocatalytic activity under visible light irradiation

    International Nuclear Information System (INIS)

    Highlights: • Liquid phase deposition is developed for preparing WO3/TiO2 heterojunction films. • TiO2 film provides an excellent platform for WO3 deposition. • WO3 expands the absorption band edge of TiO2 film to visible light region. • WO3/TiO2 heterojunction film shows high photoelectrocatalytic activity. - ABSTRACT: The heterojunction films of WO3/TiO2 were prepared by liquid phase deposition (LPD) method via two-step processes. The scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopic analysis indicated that flower-like WO3 film was successfully deposited on TiO2 film with the LPD processes. The TiO2 film provided an excellent platform for WO3 deposition while WO3 obviously expanded the absorption of TiO2 film to visible light. As the result, the heterojunction film of WO3/TiO2 exhibited higher photocurrent response to visible light illumination than pure TiO2 or WO3 film. The photoelectrocatalytic (PEC) activity of WO3/TiO2 film was evaluated by degrading Rhodamin B (RhB) and 4-chlorophenol (4-CP) under visible light irradiation. The results showed that the LPD WO3/TiO2 film possessed high PEC activity for efficient removal of various refractory organic pollutants

  7. CDK1-Cyclin B1 Activates RNMT, Coordinating mRNA Cap Methylation with G1 Phase Transcription.

    Science.gov (United States)

    Aregger, Michael; Kaskar, Aneesa; Varshney, Dhaval; Fernandez-Sanchez, Maria Elena; Inesta-Vaquera, Francisco A; Weidlich, Simone; Cowling, Victoria H

    2016-03-01

    The creation of translation-competent mRNA is dependent on RNA polymerase II transcripts being modified by addition of the 7-methylguanosine (m7G) cap. The factors that mediate splicing, nuclear export, and translation initiation are recruited to the transcript via the cap. The cap structure is formed by several activities and completed by RNMT (RNA guanine-7 methyltransferase), which catalyzes N7 methylation of the cap guanosine. We report that CDK1-cyclin B1 phosphorylates the RNMT regulatory domain on T77 during G2/M phase of the cell cycle. RNMT T77 phosphorylation activates the enzyme both directly and indirectly by inhibiting interaction with KPNA2, an RNMT inhibitor. RNMT T77 phosphorylation results in elevated m7G cap methyltransferase activity at the beginning of G1 phase, coordinating mRNA capping with the burst of transcription that occurs following nuclear envelope reformation. RNMT T77 phosphorylation is required for the production of cohort of proteins, and inhibiting T77 phosphorylation reduces the cell proliferation rate. PMID:26942677

  8. Increased Serum Phospholipase A2 Activity in Advanced Chronic Liver Disease as an Expression of the Acute Phase Response

    Directory of Open Access Journals (Sweden)

    Mario Pirisi

    1993-01-01

    Full Text Available Phospholipase A2 (PLA2 modifications were investigated in patients with acute and chronic liver diseases, PLA2 variations were related to indices of liver function as well as to parameters of the acute phase response. Serum PLA2 activity modifications were f1uorimetrically measured in 105 patients affected by acute and chronic liver diseases or extra-hepatic diseases. One-way ANOV A demonstrated a significant difference among groups (F= 4.53, P<0.001; Bonferroni’s test for pairwise comparisons showed that patients with hepatocellular carcinoma had higher mean values than subjects with benign extra-hepatic diseases (p<0.0 I and mild chronic liver disease (p<0.0S J. Multiple regression analysis, performed choosing PLA2 as the dependent variable and blood urea nitrogen, C-reacti ve protein, alkaline phosphatase and al-fetoprotein as predictor variables was significant (multiple R= 0.7056, multiple R2= 0.4978, F= 15.36, P= <0.0001. The standardized regression coefficients found to be significant were those of Creactive protein, blood urea nitrogen and al-fetoprotein. In conclusion, in patients with chronic liver disease, serum PLA2 activity increases parallel to disease severity and accompanies the expression of proteins of the acute phase response that. like PLA2 activity, increase in serum while liver synthesis declines.

  9. The role of hydration in enzyme activity and stability: 2. Alcohol dehydrogenase activity and stability in a continuous gas phase reactor.

    Science.gov (United States)

    Yang, F; Russell, A J

    1996-03-20

    The degree of enzyme hydration is the one of the most important factors which can affect enzyme activity and stability in water-limited environments. Alcohol dehydrogenase from baker's yeast (YADH) has been used as a model enzyme to study the effects of hydration on activity, stability, and cofactor stability with gas phase substrates. In all cases, the enzyme is essentially inactive until a temperature-independent degree of surface coverage by water molecules has been reached. The critical water content corresponds to 40-50% of a single monolayer. Careful control of the degree of hydration, by adjustments to gas humidity and temperature, enables the enzyme to be stabilized for periods exceeding 1 month, whereas in water the half-life of the enzyme is 30 min. The reaction with gas phase substrates follows a pseudo-first-order mechanism with an activation energy of 7.5 +/- kcal/mol, which is almost half of that in aqueous solution. (c) 1996 John Wiley & Sons, Inc.

  10. CCN activation experiments with adipic acid: effect of particle phase and adipic acid coatings on soluble and insoluble particles

    Directory of Open Access Journals (Sweden)

    S. S. Hings

    2008-07-01

    Full Text Available Slightly soluble atmospherically relevant organic compounds may influence particle CCN activity and therefore cloud formation. Adipic acid is a frequently employed surrogate for such slightly soluble organic materials. The 11 published experimental studies on the CCN activity of adipic acid particles are not consistent with each other nor do they, in most cases, agree with the Köhler theory. The CCN activity of adipic acid aerosol particles was studied over a significantly wider range of conditions than in any previous single study. The work spans the conditions of the previous studies and also provides alternate methods for producing "wet" (deliquesced solution droplets and dry adipic acid particles without the need to produce them by atomization of aqueous solutions. The experiments suggest that the scatter in the previously published CCN measurements is most likely due to the difficulty of producing uncontaminated adipic acid particles by atomization of solutions and possibly also due to uncertainties in the calibration of the instruments. The CCN activation of the small (dm<150 nm initially dry particles is subject to a deliquescence barrier, while for the larger particles the activation follows the Köhler curve. Wet adipic acid particles follow the Köhler curve over the full range of particle diameters studied. In addition, the effect of adipic acid coatings on the CCN activity of both soluble and insoluble particles has also been studied. When a water-soluble core is coated by adipic acid, the CCN-hindering effect of particle phase is eliminated. An adipic acid coating on hydrophobic soot yields a CCN active particle. If the soot particle is relatively small (dcore≤102 nm, the CCN activity of the coated particles approaches the deliquescence line of adipic acid, suggesting that the total size of the particle determines CCN activation and the soot core acts as a scaffold.

  11. Complement lysis activity in autologous plasma is associated with lower viral loads during the acute phase of HIV-1 infection.

    Directory of Open Access Journals (Sweden)

    Michael Huber

    2006-11-01

    Full Text Available BACKGROUND: To explore the possibility that antibody-mediated complement lysis contributes to viremia control in HIV-1 infection, we measured the activity of patient plasma in mediating complement lysis of autologous primary virus. METHODS AND FINDINGS: Sera from two groups of patients-25 with acute HIV-1 infection and 31 with chronic infection-were used in this study. We developed a novel real-time PCR-based assay strategy that allows reliable and sensitive quantification of virus lysis by complement. Plasma derived at the time of virus isolation induced complement lysis of the autologous virus isolate in the majority of patients. Overall lysis activity against the autologous virus and the heterologous primary virus strain JR-FL was higher at chronic disease stages than during the acute phase. Most strikingly, we found that plasma virus load levels during the acute but not the chronic infection phase correlated inversely with the autologous complement lysis activity. Antibody reactivity to the envelope (Env proteins gp120 and gp41 were positively correlated with the lysis activity against JR-FL, indicating that anti-Env responses mediated complement lysis. Neutralization and complement lysis activity against autologous viruses were not associated, suggesting that complement lysis is predominantly caused by non-neutralizing antibodies. CONCLUSIONS: Collectively our data provide evidence that antibody-mediated complement virion lysis develops rapidly and is effective early in the course of infection; thus it should be considered a parameter that, in concert with other immune functions, steers viremia control in vivo.

  12. Gene expression profiling of porcine skeletal muscle in the early recovery phase following acute physical activity

    DEFF Research Database (Denmark)

    Hansen, Jeanette; Conley, Lene; Hedegaard, Jakob;

    2012-01-01

    Acute physical activity elicits changes in gene expression in skeletal muscles to promote metabolic changes and to repair exercise-induced muscle injuries. In the present time-course study, pigs were submitted to an acute bout of treadmill running until near exhaustion to determine the impact...... detected an upregulation of genes that are associated with muscle cell proliferation and differentiation, including MUSTN1, ASB5 and CSRP3, possibly reflecting activation, differentiation and fusion of satellite cells to facilitate repair of muscle damage. In addition, exercise increased expression...... of adenosine-to-inosine edited mRNAs in the ribonucleoprotein bodies called paraspeckles. These findings expand the complexity of pathways affected by acute contractile activity of skeletal muscle, contributing to a better understanding of the molecular processes that occur in muscle tissue in the recovery...

  13. Magnetic force driven six degree-of-freedom active vibration isolation system using a phase compensated velocity sensor

    International Nuclear Information System (INIS)

    A six-axis active vibration isolation system (AVIS) is developed using voice coil actuators. Point contact configuration is employed to have an easy assembly of eight voice coil actuators to an upper and a base plates. The velocity sensor, using an electromagnetic principle that is commonly used in the vibration control, is investigated since its phase lead characteristic causes an instability problem for a low frequency vibration. The performances of the AVIS are investigated in the frequency domain and finally validated by comparing with the passive isolation system using the atomic force microscope images.

  14. Controller design and implementation of a three-phase Active Front End using SiC based MOSFETs

    DEFF Research Database (Denmark)

    Haase, Frerk; Kouchaki, Alireza; Nymand, Morten

    2015-01-01

    The design and implementation of a three phase Active Front End for power factor correction purposes using fast switching SiC based MOSFETs is presented. Possible applications are within the drives- and renewable energy sector. The controller is designed and implemented in the synchronous rotating...... reference frame. Besides the theoretical modelling the controller is optimized through simulations and implemented on a low cost DSP processor using a visual programming language - here MATLAB/SIMULINK - with automatic code generation for embedded targets. The paper illustrates the advantages of power...

  15. Reduction of dc-link capacitance for three-phase three-wire shunt active power filters

    DEFF Research Database (Denmark)

    Jin, Chi; Tang, Yi; Wang, Peng;

    2013-01-01

    Three-phase three-wire shunt active power filters (APFs) usually employ very large electrolytic capacitors in the dc-link to mitigate utility side harmonics. These capacitors are however known to be bulky and of short operating lifetime, particularly for systems where high ripple currents exist....... This paper presents the concept of dc-link compensator (DLC) that aims to decouple the harmonic power from the dc-link of APF. With proper system sizing and design, most of the harmonic power can be eliminated by this DLC circuit and very small electrolytic capacitors or even film type capacitors can be used...

  16. Propeller-Like Nanorod-Upconversion Nanoparticle Assemblies with Intense Chiroptical Activity and Luminescence Enhancement in Aqueous Phase.

    Science.gov (United States)

    Wu, Xiaoling; Xu, Liguang; Ma, Wei; Liu, Liqiang; Kuang, Hua; Kotov, Nicholas A; Xu, Chuanlai

    2016-07-01

    Propeller-like nanoscale assemblies with exceptionally intense chiroptical activity and strong luminescence are prepared using gold nanorods and upconversion nanoparticles. The circular dichroism intensity of the tetramer reached 80.9 mdeg, with g-factor value of 2.1 × 10(-2) . The enhancement factor of upconversion luminescence is as high as 21.3 in aqueous phase. Attomolar bioanalysis of a cancer biomarker with two model is also achieved, showing potential for early disease diagnosis and environmental monitoring. PMID:27158947

  17. Sintering activation of 316L powder using a liquid phase forming powder

    Directory of Open Access Journals (Sweden)

    Nattaya Tosangthum

    2010-03-01

    Full Text Available It was found that the addition of a liquid forming powder (up to 6 wt.% of a gas-atomized tin powder to 316L powdercould activate the sintering process. Sintering activation could be observed by an increase of the sintered density and selected mechanical properties. When optimized tin powder content was used, shorter sintering time and lower sintering temperaturecould produce sintered 316L+tin materials with excellent mechanical properties. Electron dispersive spectroscopy analyses across 316L-tin-316L grains indicated that Ni transportation during the sintering process was enhanced by the presence of liquid tin.

  18. Phase coupling of a circadian neuropeptide with rest/activity rhythms detected using a membrane-tethered spider toxin.

    Directory of Open Access Journals (Sweden)

    Ying Wu

    2008-11-01

    induces rhythmic action potential bursts and depolarized plateau potentials. These in vitro and in vivo electrophysiological effects of membrane-tethered delta-ACTX-Hv1a are consistent with the effects of soluble delta-ACTX-Hv1a purified from venom on Na(+ channel physiological and biophysical properties in cockroach neurons. Membrane-tethered delta-ACTX-Hv1a expression in the PDF-secreting subset of clock neurons induces an approximately 4-h phase advance of the rhythm of PDF accumulation in their terminals relative to both the phase of the day:night cycle and the phase of the circadian transcriptional feedback loops. As a consequence, the morning anticipatory peak of locomotor activity preceding dawn, which has been shown to be driven by the clocks of the PDF-secreting subset of clock neurons, phase advances coordinately with the phase of the PDF rhythm of the PDF-secreting clock neurons, rather than maintaining its phase relationship with the day:night cycle and circadian transcriptional feedback loops. These results (1 validate the tethered-toxin technology for cell-autonomous modulation of ion channel biophysical properties in vivo in transgenic Drosophila, (2 demonstrate that the kinetics of para Na(+ channel inactivation is a key parameter for determining the phase relationship between circadian transcriptional feedback oscillation and PDF secretion, and (3 provide experimental support for the hypothesis that PDF-secreting clock neurons entrain the phase of organismal rhythms via the temporal patterning of secreted PDF signals.

  19. Complement activation patterns in atypical haemolytic uraemic syndrome during acute phase and in remission

    NARCIS (Netherlands)

    Volokhina, E.B.; Westra, D.; Velden, T.J.A.M. van der; Kar, N.C.A.J. van de; Mollnes, T.E.; Heuvel, B. van den

    2015-01-01

    Atypical haemolytic uraemic syndrome (aHUS) is associated with (genetic) alterations in alternative complement pathway. Nevertheless, comprehensive evidence that the complement system in aHUS patients is more prone to activation is still lacking. Therefore, we performed a thorough analysis of comple

  20. Solid-phase synthesis of new saphenamycin analogues with antimicrobial activity

    DEFF Research Database (Denmark)

    Laursen, Jane B.; De Visser, Peter C.; Nielsen, Henrik K.;

    2002-01-01

    in parallel with a series of differently substituted benzoic acid derivatives. Treatment with TFA-CH2Cl2 (5:995) released the expected saphenamycin analogues into solution. These new analogues were purified, characterized and screened for antimicrobial activity against Bacillus subtilis and Proteus mirabilis...

  1. The Science of Chocolate: Interactive Activities on Phase Transitions, Emulsification, and Nucleation

    Science.gov (United States)

    Rowat, Amy C.; Hollar, Kathryn A.; Stone, Howard A.; Rosenberg, Daniel

    2011-01-01

    Nearly everyone loves chocolate, which makes this an excellent topic for communicating scientific concepts to the general public and to students in the classroom. Here we present the outline and activities for an interactive presentation on the science of chocolate for nonspecialists and their children ages 6 and up. We design the presentation…

  2. Active-Set Reduced-Space Methods with Nonlinear Elimination for Two-Phase Flow Problems in Porous Media

    KAUST Repository

    Yang, Haijian

    2016-07-26

    Fully implicit methods are drawing more attention in scientific and engineering applications due to the allowance of large time steps in extreme-scale simulations. When using a fully implicit method to solve two-phase flow problems in porous media, one major challenge is the solution of the resultant nonlinear system at each time step. To solve such nonlinear systems, traditional nonlinear iterative methods, such as the class of the Newton methods, often fail to achieve the desired convergent rate due to the high nonlinearity of the system and/or the violation of the boundedness requirement of the saturation. In the paper, we reformulate the two-phase model as a variational inequality that naturally ensures the physical feasibility of the saturation variable. The variational inequality is then solved by an active-set reduced-space method with a nonlinear elimination preconditioner to remove the high nonlinear components that often causes the failure of the nonlinear iteration for convergence. To validate the effectiveness of the proposed method, we compare it with the classical implicit pressure-explicit saturation method for two-phase flow problems with strong heterogeneity. The numerical results show that our nonlinear solver overcomes the often severe limits on the time step associated with existing methods, results in superior convergence performance, and achieves reduction in the total computing time by more than one order of magnitude.

  3. Lysine-Based Small Molecules That Disrupt Biofilms and Kill both Actively Growing Planktonic and Nondividing Stationary Phase Bacteria.

    Science.gov (United States)

    Konai, Mohini M; Haldar, Jayanta

    2015-10-01

    The emergence of bacterial resistance is a major threat to global health. Alongside this issue, formation of bacterial biofilms is another cause of concern because most antibiotics are ineffective against these recalcitrant microbial communities. Ideal future antibacterial therapeutics should possess both antibacterial and anti-biofilm activities. In this study we engineered lysine-based small molecules, which showed not only commendable broad-spectrum antibacterial activity but also potent biofilm-disrupting properties. Synthesis of these lipophilic lysine-norspermidine conjugates was achieved in three simple reaction steps, and the resultant molecules displayed potent antibacterial activity against various Gram-positive (Staphylococcus aureus, Enterococcus faecium) and Gram-negative bacteria (Escherichia coli) including drug-resistant superbugs MRSA (methicillin-resistant S. aureus), VRE (vancomycin-resistant E. faecium), and β-lactam-resistant Klebsiella pneumoniae. An optimized compound in the series showed activity against planktonic bacteria in the concentration range of 3-10 μg/mL, and bactericidal activity against stationary phase S. aureus was observed within an hour. The compound also displayed about 120-fold selectivity toward both classes of bacteria (S. aureus and E. coli) over human erythrocytes. This rapidly bactericidal compound primarily acts on bacteria by causing significant membrane depolarization and K(+) leakage. Most importantly, the compound disrupted preformed biofilms of S. aureus and did not trigger bacterial resistance. Therefore, this class of compounds has high potential to be developed as future antibacterial drugs for treating infections caused by planktonic bacteria as well as bacterial biofilms. PMID:27623313

  4. High rate mesophilic, thermophilic, and temperature phased anaerobic digestion of waste activated sludge: A pilot scale study

    International Nuclear Information System (INIS)

    Highlights: ► High temperatures were tested in single and two-stage anaerobic digestion of waste activated sludge. ► The increased temperature demonstrated the possibility of improving typical yields of the conventional mesophilic process. ► The temperature phased anaerobic digestion process (65 + 55 °C) showed the best performances with yields of 0.49 m3/kgVSfed. ► Ammonia and phosphate released from solids destruction determined the precipitation of struvite in the reactor. - Abstract: The paper reports the findings of a two-year pilot scale experimental trial for the mesophilic (35 °C), thermophilic (55 °C) and temperature phased (65 + 55 °C) anaerobic digestion of waste activated sludge. During the mesophilic and thermophilic runs, the reactor operated at an organic loading rate of 2.2 kgVS/m3d and a hydraulic retention time of 20 days. In the temperature phased run, the first reactor operated at an organic loading rate of 15 kgVS/m3d and a hydraulic retention time of 2 days while the second reactor operated at an organic loading rate of 2.2 kgVS/m3d and a hydraulic retention time of 18 days (20 days for the whole temperature phased system). The performance of the reactor improved with increases in temperature. The COD removal increased from 35% in mesophilic conditions, to 45% in thermophilic conditions, and 55% in the two stage temperature phased system. As a consequence, the specific biogas production increased from 0.33 to 0.45 and to 0.49 m3/kgVSfed at 35, 55, and 65 + 55 °C, respectively. The extreme thermophilic reactor working at 65 °C showed a high hydrolytic capability and a specific yield of 0.33 gCOD (soluble) per gVSfed. The effluent of the extreme thermophilic reactor showed an average concentration of soluble COD and volatile fatty acids of 20 and 9 g/l, respectively. Acetic and propionic acids were the main compounds found in the acids mixture. Because of the improved digestion efficiency, organic nitrogen and phosphorus were

  5. Pre-Launch Phase 1 Calibration and Validation Rehearsal of Geophysical Data Products of Soil Moisture Active Passive (SMAP) Mission

    Science.gov (United States)

    Colliander, A.; Jackson, T. J.; Chan, S.; Dunbar, R.; Das, N. N.; Kim, S.; Reichle, R. H.; De Lannoy, G. J.; Liu, Q.; Kimball, J. S.; Yi, Y.; Cosh, M. H.; Bindlish, R.; Crow, W. T.; Dang, L.; Yueh, S. H.; Njoku, E. G.

    2013-12-01

    NASA's Soil Moisture Active Passive (SMAP) Mission is scheduled for launch in October 2014. The objective of the mission is global mapping of soil moisture and freeze/thaw state. SMAP utilizes an L-band radar and radiometer sharing a rotating 6-meter mesh reflector antenna. The instruments will operate onboard the SMAP spacecraft in a 685-km Sun-synchronous near-polar orbit, viewing the surface at a constant 40-degree incidence angle with a 1000-km swath width. Merging of active and passive L-band observations of the mission will enable an unprecedented combination of accuracy, resolution, coverage and revisit-time for soil moisture and freeze/thaw state retrieval. SMAP measurements will enable significantly improved estimates of water, energy and carbon transfers between the land and atmosphere. The SMAP science data product suite of geophysical parameters will include estimates of surface (top 5 cm) and root-zone (down to 1-m depth) soil moisture, net ecosystem exchange, and classification of the frozen/non-frozen state of the landscape. The primary validation reference of the data products will be ground-based measurements. Other remote sensing and model-based products will be used as additional resources. The post-launch timeline of the mission requires that the geophysical data products are validated (with respect to the mission requirements) within 12 months after a 3-month in-orbit check-out phase. SMAP is taking several preparatory steps in order to meet this schedule. One of the main steps consists of running a rehearsal to exercise calibration and validation procedures planned for the Cal/Val Phase. The rehearsal is divided into two stages. Phase 1, which was conducted in June-August 2013, focused on validation methodologies for the geophysical data products. Phase 2, which will be conducted in May-June 2014, includes operational aspects including a fully functioning SMAP Science Data System. (Note that the rehearsals do not include an airborne field

  6. [THERAPEUTIC ACTIVITY OF MICRONIZED MEBENDAZOLE IN THE MUSCULAR PHASE OF EXPERIMENTAL TRICHINELLA SPIRALIS INVASION IN ALBINO MICE].

    Science.gov (United States)

    Kukhaleva, I V; Kovalenko, F P; Shkolyar, N A; Legonkov, Yu A; Musaev, A Kh; Bulanova, T E; Samochatova, E I

    2015-01-01

    The incidence of trichinosis in Russia was 0.07 per 100,000 population in 2014, which was 2.9-fold higher than that in 2013. Two WHO recommended medications mebendazole and albendazole are now used to treat humari trichinosis. The drugs are active against only mature helminths and non-encysted muscle larvae. The original oil suspension of micronized mebendazole was.found to have 100% efficacy against trichinosis in albino mice in the late muscular phase (encysted larvae) of hyperinvasion after intensive therapy under lifetime diagnostic guidance during and after a treatment cycle. The lifetime diagnostic method used to evaluate the larvicidal activity of anti-trichinosis agents in animals with experimental trichinosis revealed the signs of viaility, established a trend for deatih of Trichinella larvae, and determined their destructive changes. PMID:26827586

  7. Optically Controlled 30 GHz High Power Active RF Phase Switch for the CTF3 RF Pulse Compressor

    CERN Document Server

    Syratchev, Igor V; Kocharovsky, Vl; Kuzukov, S; Stepanov, A

    2005-01-01

    To achieve the high peak power level of 150 MW, necessary to demonstrate the full performance of the new CLIC accelerating structure, a 70 ns RF pulse compressor with resonant delay lines has been built and installed in the CTF3 test area. An active high power RF phase switch would make the operation of the whole 30 GHz power production complex more reliable and robust, with the potential to increase the compression efficiency. By itself, such a device can be used for many other applications. In this paper we propose a possible solution based on an over-moded RF circuit with active element made from a semiconductor controlled by a laser beam.

  8. SiC MOSFET Based Single Phase Active Boost Rectifier with Power Factor Correction for Wireless Power Transfer Applications

    Energy Technology Data Exchange (ETDEWEB)

    Onar, Omer C [ORNL; Tang, Lixin [ORNL; Chinthavali, Madhu Sudhan [ORNL; Campbell, Steven L [ORNL; Miller (JNJ), John M. [JNJ-Miller PLC

    2014-01-01

    Wireless Power Transfer (WPT) technology is a novel research area in the charging technology that bridges the utility and the automotive industries. There are various solutions that are currently being evaluated by several research teams to find the most efficient way to manage the power flow from the grid to the vehicle energy storage system. There are different control parameters that can be utilized to compensate for the change in the impedance due to variable parameters such as battery state-of-charge, coupling factor, and coil misalignment. This paper presents the implementation of an active front-end rectifier on the grid side for power factor control and voltage boost capability for load power regulation. The proposed SiC MOSFET based single phase active front end rectifier with PFC resulted in >97% efficiency at 137mm air-gap and >95% efficiency at 160mm air-gap.

  9. Recent tectonic activity on Pluto driven by phase changes in the ice shell

    Science.gov (United States)

    Hammond, Noah P.; Barr, Amy C.; Parmentier, Edgar M.

    2016-07-01

    The New Horizons spacecraft has found evidence for geologic activity on the surface of Pluto, including extensional tectonic deformation of its water ice bedrock see Moore et al. (2016). One mechanism that could drive extensional tectonic activity is global surface expansion due to the partial freezing of an ocean. We use updated physical properties for Pluto and simulate its thermal evolution to understand the survival of a possible subsurface ocean. For thermal conductivities of rock less than 3 W m-1 K-1, an ocean forms and at least partially freezes, leading to recent extensional stresses in the ice shell. In scenarios where the ocean freezes and the ice shell is thicker than 260 km, ice II forms and causes global volume contraction. Since there is no evidence for recent compressional tectonic features, we argue that ice II has not formed and that Pluto's ocean has likely survived to present day.

  10. Recent Tectonic Activity on Pluto Driven by Phase Changes in the Ice Shell

    CERN Document Server

    Hammond, Noah P; Parmentier, Edgar M

    2016-01-01

    The New Horizons spacecraft has found evidence for geologic activity on the surface of Pluto, including extensional tectonic deformation of its water ice bedrock (see Moore et al., 2016). One mechanism that could drive extensional tectonic activity is global surface expansion due to the partial freezing of an ocean. We use updated physical properties for Pluto and simulate its thermal evolution to understand the survival of a possible subsurface ocean. For thermal conductivities of rock less than 3 W m$^{-1}$ K$^{-1}$, an ocean forms and at least partially freezes, leading to recent extensional stresses in the ice shell. In scenarios where the ocean freezes and the ice shell is thicker than $260$ km, ice II forms and causes global volume contraction. Since there is no evidence for recent compressional tectonic features, we argue that ice II has not formed and that Pluto's ocean has likely survived to present day.

  11. Acute coagulopathy of trauma: balancing progressive catecholamine induced endothelial activation and damage by fluid phase anticoagulation

    DEFF Research Database (Denmark)

    Johansson, P I; Ostrowski, S R

    2010-01-01

    Acute coagulopathy of trauma predicts a poor clinical outcome. Tissue trauma activates the sympathoadrenal system resulting in high circulating levels of catecholamines that influence hemostasis dose-dependently through immediate effects on the two major compartments of hemostasis, i.e., the...... circulating blood and the vascular endothelium. There appears to be a dose-dependency with regards to injury severity and the hemostatic response to trauma evaluated in whole blood by viscoelastic assays like thrombelastography (TEG), changing from normal to hypercoagulable, to hypocoagulable and finally...... evolutionary developed response that counterbalances the injury and catecholamine induced endothelial activation and damage. Given this, the rise in circulating catecholamines in trauma patients may favor a switch from hyper- to hypocoagulability in the blood to keep the progressively more procoagulant...

  12. The effect of doping titanium dioxide nanoparticles on phase transformation, photocatalytic activity and anti-bacterial properties

    Science.gov (United States)

    Buzby, Scott Edward

    Nanosized titanium dioxide has a variety of important applications in everyday life including a photocatalyst for pollution remediation, photovoltaic devices, sunscreen, etc. This study focuses on the various properties of titanium dioxide nanoparticles doped with various cation and anion species. Samples were produced by various methods including metalorganic chemical vapor deposition (MOCVD), plasma assisted metalorganic chemical vapor deposition (PA-MOCVD) and sol-gel. Numerous techniques such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electron microscopy both scanning (SEM) and transmission (TEM) were used for physical characterization. Photocatalytic properties were determined by the oxidation of methylene blue dye and 2-chlorophenol in water as well as gaseous formic acid with results analyzed by high performance liquid chromatography (HPLC), Fourier transform infrared spectroscopy (FTIR) and ultra violet - visible spectroscopy (UV-VIS). For the purpose of enhancement of the photocatalytic activity of titanium dioxide nanoparticles, the effect of anion doping and the anatase-rutile phase ratio were studied. Although anatase, rutile and mixed crystallite phases all show some degree of activity in photocatalytic reactions, these results show that anatase is better suited for the degradation of organic compounds in an aqueous medium any advantage in photocatalytic activity gained through the enhancement in optical response from the smaller band gap by addition of rutile was overcome by the negatives associated with the rutile phase. Furthermore substitutional nitrogen doping showed significant improvement in UV photocatalysis as well as allowing for visible light activation of the catalyst. Further studies on the phase transitions in titanium dioxide nanoparticles were carried out by synthesizing various cation doped samples by sol-gel. Analysis of the phases by XRD showed an inverse relationship between dopant size and rutile percentage

  13. Effect of graded Nrf2 activation on phase-I and -II drug metabolizing enzymes and transporters in mouse liver.

    Directory of Open Access Journals (Sweden)

    Kai Connie Wu

    Full Text Available Nuclear factor erythroid 2-related factor 2 (Nrf2 is a transcription factor that induces a battery of cytoprotective genes in response to oxidative/electrophilic stress. Kelch-like ECH associating protein 1 (Keap1 sequesters Nrf2 in the cytosol. The purpose of this study was to investigate the role of Nrf2 in regulating the mRNA of genes encoding drug metabolizing enzymes and xenobiotic transporters. Microarray analysis was performed in livers of Nrf2-null, wild-type, Keap1-knockdown mice with increased Nrf2 activation, and Keap1-hepatocyte knockout mice with maximum Nrf2 activation. In general, Nrf2 did not have a marked effect on uptake transporters, but the mRNAs of organic anion transporting polypeptide 1a1, sodium taurocholate cotransporting polypeptide, and organic anion transporter 2 were decreased with Nrf2 activation. The effect of Nrf2 on cytochrome P450 (Cyp genes was minimal, with only Cyp2a5, Cyp2c50, Cyp2c54, and Cyp2g1 increased, and Cyp2u1 decreased with enhanced Nrf2 activation. However, Nrf2 increased mRNA of many other phase-I enzymes, such as aldo-keto reductases, carbonyl reductases, and aldehyde dehydrogenase 1. Many genes involved in phase-II drug metabolism were induced by Nrf2, including glutathione S-transferases, UDP- glucuronosyltransferases, and UDP-glucuronic acid synthesis enzymes. Efflux transporters, such as multidrug resistance-associated proteins, breast cancer resistant protein, as well as ATP-binding cassette g5 and g8 were induced by Nrf2. In conclusion, Nrf2 markedly alters hepatic mRNA of a large number of drug metabolizing enzymes and xenobiotic transporters, and thus Nrf2 plays a central role in xenobiotic metabolism and detoxification.

  14. A Precursory Phase to a Sudden Enhanced Activity at Yasur volcano (Vanuatu) : Insights from Simultaneous Infrasonic and Seismic Records

    Science.gov (United States)

    Vergniolle, S.; Zielinski, C.; Battaglia, J.; Metaxian, J. P.; Bani, P.; LE Pichon, A.; Lardy, M.; Millier, P.; Frogneux, M.; Gallois, F.; Herry, P.; Todman, S.; Garaebiti, E.

    2015-12-01

    The permanent activity at Yasur (Vanuatu), characterised by a close series of Strombolian explosions, is analysed using simultaneous infrasonic and seismic recordings (6-25 Nov 2008) close to the vents. The RMS amplitudes per hour, the number of explosions and the peak-to-peak amplitudes of each signal show that the initial quiet phase (11 days) is followed by a precursory phase (7 days) prior to an enhanced activity (17 hours). Three periods exist during the strong activity: (1) a rapid increase leading to the paroxysm (3 hours), (2) a first (5 hours) and (3) a second decrease (9 hours), each having an excellent correlation between seismic and infrasonic RMS amplitudes per hour (correlation coefficient > 0.96) when using the band associated to explosions (1-5 Hz and 1.8-4 Hz for seismic and infrsonic recordings, respectively). The ratio between infrasonic and seismic RMS amplitudes, assumed to be a proxy for the magma level, increases strongly during the week before the paroxysm. This is explained by the arrival of an additional gas flux at the top of the reservoir. The foam accumulated there, whose partial coalescence and spreading towards the conduit are responsible for the permanent Strombolian activity, thickens. This enhances both the viscous massive foam coalescence and the foam spreading. This leads to an increase in the gas flux in the conduit, ultimately responsible for the formation of a shallow foam at the surface. This foam acts as a viscous cap overlying the magma column, thereby increasing the radiated infrasonic pressure and the strength of the explosions. The first decrease in the relationship between infrasonic and seismic RMS amplitudes is associated with the stopping of the additionnal gas flux in the magma reservoir and the rapid decrease of the top of the magma column due to the previous intense degassing. The second decrease corresponds to the time neccessary to restore the convective motions in the conduit at their normal velocities.

  15. Activity Increase Despite Arthritis (AÏDA: design of a Phase II randomised controlled trial evaluating an active management booklet for hip and knee osteoarthritis [ISRCTN24554946

    Directory of Open Access Journals (Sweden)

    Edwards Rhiannon T

    2009-09-01

    Full Text Available Abstract Background Hip and knee osteoarthritis is a common cause of pain and disability, which can be improved by exercise interventions. However, regular exercise is uncommon in this group because the low physical activity level in the general population is probably reduced even further by pain related fear of movement. The best method of encouraging increased activity in this patient group is not known. A booklet has been developed for patients with hip or knee osteoarthritis. It focuses on changing disadvantageous beliefs and encouraging increased physical activity. Methods/Design This paper describes the design of a Phase II randomised controlled trial (RCT to test the effectiveness of this new booklet for patients with hip and knee osteoarthritis in influencing illness and treatment beliefs, and to assess the feasibility of conducting a larger definitive RCT in terms of health status and exercise behaviour. A computerised search of four general medical practice patients' record databases will identify patients older than 50 years of age who have consulted with hip or knee pain in the previous twelve months. A random sample of 120 will be invited to participate in the RCT comparing the new booklet with a control booklet, and we expect 100 to return final questionnaires. This trial will assess the feasibility of recruitment and randomisation, the suitability of the control intervention and outcome measurement tools, and will provide an estimate of effect size. Outcomes will include beliefs about hip and knee pain, beliefs about exercise, fear avoidance, level of physical activity, health status and health service costs. They will be measured at baseline, one month and three months. Discussion We discuss the merits of testing effectiveness in a phase II trial, in terms of intermediate outcome measures, whilst testing the processes for a larger definitive trial. We also discuss the advantages and disadvantages of testing the psychometric

  16. Immobilized enzyme reactor chromatography: Optimization of protein retention and enzyme activity in monolithic silica stationary phases

    Energy Technology Data Exchange (ETDEWEB)

    Besanger, Travis R. [Department of Chemistry, McMaster University, 1280 Main St. West, Hamilton, Ont. L8S 4M1 (Canada); Hodgson, Richard J. [Department of Chemistry, McMaster University, 1280 Main St. West, Hamilton, Ont. L8S 4M1 (Canada); Green, James R.A. [Department of Chemistry, McMaster University, 1280 Main St. West, Hamilton, Ont. L8S 4M1 (Canada); Brennan, John D. [Department of Chemistry, McMaster University, 1280 Main St. West, Hamilton, Ont. L8S 4M1 (Canada)]. E-mail: brennanj@mcmaster.ca

    2006-03-30

    Our group recently reported on the application of protein-doped monolithic silica columns for immobilized enzyme reactor chromatography, which allowed screening of enzyme inhibitors present in mixtures using mass spectrometry for detection. The enzyme was immobilized by entrapment within a bimodal meso/macroporous silica material prepared by a biocompatible sol-gel processing route. While such columns proved to be useful for applications such as screening of protein-ligand interactions, significant amounts of entrapped proteins leached from the columns owing to the high proportion of macropores within the materials. Herein, we describe a detailed study of factors affecting the morphology of protein-doped bioaffinity columns and demonstrate that specific pH values and concentrations of poly(ethylene glycol) can be used to prepare essentially mesoporous columns that retain over 80% of initially loaded enzyme in an active and accessible form and yet still retain sufficient porosity to allow pressure-driven flow in the low {mu}L/min range. Using the enzyme {gamma}-glutamyl transpeptidase ({gamma}-GT), we further evaluated the catalytic constants of the enzyme entrapped in capillary columns with different silica morphologies as a function of flowrate and backpressure using the enzyme reactor assay mode. It was found that the apparent activity of the enzyme was highest in mesoporous columns that retained high levels of enzyme. In such columns, enzyme activity increased by {approx}2-fold with increases in both flowrate (from 250 to 1000 nL/min) and backpressure generated (from 500 to 2100 psi) during the chromatographic activity assay owing to increases in k {sub cat} and decreases in K {sub M}, switching from diffusion controlled to reaction controlled conditions at ca. 2000 psi. These results suggest that columns with minimal macropore volumes (<5%) are advantageous for the entrapment of soluble proteins for bioaffinity and bioreactor chromatography.

  17. Mechanistic Variants in Gas-Phase Metal-Oxide Mediated Activation of Methane at Ambient Conditions.

    Science.gov (United States)

    Li, Jilai; Zhou, Shaodong; Zhang, Jun; Schlangen, Maria; Usharani, Dandamudi; Shaik, Sason; Schwarz, Helmut

    2016-09-01

    The C-H bond activation of methane mediated by a prototypical heteronuclear metal-oxide cluster, [Al2Mg2O5](•+), was investigated by using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) in conjunction with high-level quantum mechanical calculations. Experimentally, hydrogen-atom abstraction from methane by the cluster ion [Al2Mg2O5](•+) takes place at ambient conditions. As to the mechanism, according to our computational findings, both the proton-coupled electron transfer (PCET) and the conventional hydrogen-atom transfer (HAT) are feasible and compete with each other. This is in distinct contrast to the [XYO2](+) (X, Y = Mg, Al, Si) cluster oxide ions which activate methane exclusively via the PCET route (Li, J.; Zhou, S.; Zhang, J.; Schlangen, M.; Weiske, T.; Usharani, D.; Shaik, S.; Schwarz, H. J. Am. Chem. Soc. 2016, 138, 7973-7981). The electronic origins of the mechanistically rather complex reactivity scenarios of the [Al2Mg2O5](•+)/CH4 couple were elucidated. For the PCET mechanism, in which the Lewis acid-base pair [Al(+)-O(-)] of the cluster acts as the active site, a clear correlation has been established between the nature of the transition state, the corresponding barrier height, the Lewis acidity-basicity of the [M(+)-O(-)] unit, as well as the bond order of the M(+)-O(-) bond. Also addressed is the role of the spin and charge distributions of a terminal oxygen radical site in the direct HAT route. The knowledge of the factors that control the reactivity of PCET and HAT pathways not only deepens our mechanistic understanding of metal-oxide mediated C-H bond activation but may also provide guidance for the rational design of catalysts. PMID:27518766

  18. Nongenotoxic p53 activation protects cells against S-phase-specific chemotherapy

    DEFF Research Database (Denmark)

    Kranz, Dominique; Dobbelstein, Matthias

    2006-01-01

    Mutations in the tumor suppressor gene TP53 represent the most frequent genetic difference between tumor cells and normal cells. Here, we have attempted to turn this difference into an advantage for normal cells during therapy. Using the Mdm2 antagonist nutlin-3, we first activated p53 in U2OS an...... a killer to a protector of cells, with the potential to reduce unwanted side effects of chemotherapy....

  19. Regional inventory of karst activity in the Valley and Ridge Province, eastern Tennessee: Phase 1

    International Nuclear Information System (INIS)

    A data collection form was developed for use in compiling information in the inventory. Information sources included files on subsidence, state and county highway departments, county agents and executives, soil conservation service representative, etc. Data obtained included location, date of occurrence, number of subsidence features at the reported site, size, topographic setting, geologic setting, and probable causative factors. The regional inventory obtained information on over 300 historic subsidence events at more than 200 sites in East Tennessee. Areas having the greatest areal density of active subsidence include Hamblen, Jefferson, and Loudon Counties. Reported subsidence events occurred between 1945 and 1986. The Knox Group dolomites account for about two-thirds of all reported sinkholes in the inventory. Most of the karst activity occurs in valleys or flat areas. In cases where causative factors could be established, the combination of surface water drainage alteration or impoundment combined with soil disturbance associated with construction activity were most often precursors to subsidence. 54 refs., 10 figs., 4 tabs

  20. An experimental and numerical simulation study of an active solar wall enhanced with phase change materials

    Directory of Open Access Journals (Sweden)

    Dionysios I. Kolaitis

    2015-06-01

    Full Text Available Solar walls can be used to increase the overall energy efficiency of a building. Phase Change Materials (PCM are capable of increasing the effective thermal mass of building elements, thus decreasing the overall energy consumption. Recently, the incorporation of PCM in a solar wall has been proposed, aiming to increase the total energy efficiency of the system. The main scope of this work is to investigate the thermal behaviour of a PCM-enhanced solar wall (PCMESW, using experimental and numerical simulation techniques. A prototype PCMESW is installed in a large-scale test facility and is exposed to dynamically changing climate conditions. A broad range of sensors, used to monitor the time-evolution of several important physical parameters, is employed to assess the dynamic response of the PCMESW. In addition, a Computational Fluid Dynamics tool is used to numerically investigate the thermal behaviour of the PCMESW prototype. Predictions of the developing flow- and thermal-field in the PCMESW’s air cavity are validated by means of comparison with the obtained measurements; in general, good levels of agreement are observed. Results of the numerical simulations may support the design optimization process of innovative PCMESW systems.  

  1. Catalyst activity maintenance study for the liquid phase dimethyl ether process

    Energy Technology Data Exchange (ETDEWEB)

    Peng, X.D.; Toseland, B.A.; Underwood, R.P. [Air Products and Chemicals, Inc., Allentown, PA (United States)

    1995-12-31

    The co-production of dimethyl ether (DME) and methanol from syngas is a process of considerable commercial attractiveness. DME coproduction can double the productivity of a LPMEOH process when using coal-derived syngas. This in itself may offer chemical producers and power companies increased flexibility and more profitable operation. DME is also known as a clean burning liquid fuel; Amoco and Haldor-Topsoe have recently announced the use of DME as an alternative diesel fuel. Moreover, DME can be an interesting intermediate in the production of chemicals such as olefins and vinyl acetate. The current APCl liquid phase dimethyl ether (LPDME) process utilizes a physical mixture of a commercial methanol synthesis catalyst and a dehydration catalyst (e.g., {gamma}-alumina). While this arrangement provides a synergy that results in much higher syngas conversion per pass compared to the methanol-only process, the stability of the catalyst system suffers. The present project is aimed at reducing catalyst deactivation both by understanding the cause(s) of catalyst deactivation and by developing modified catalyst systems. This paper describes the current understanding of the deactivation mechanism.

  2. A convenient solution-phase method for the preparation of meta-iodobenzylguanidine in high effective specific activity

    Energy Technology Data Exchange (ETDEWEB)

    Donovan, Amanda C. [Departments of Chemistry and Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, ON, Canada, L8S 4M1 (Canada); Valliant, John F. [Departments of Chemistry and Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, ON, L8S 4M1 (Canada)], E-mail: valliant@mcmaster.ca

    2008-10-15

    Introduction: There is a need for new methods of producing receptor-targeted molecular radioimaging and radiotherapy agents in high effective specific activity. This is particularly true for targets that are expressed in relatively low concentrations. Methods: A highly fluorinated (fluorous) tin precursor of meta-iodobenzylguanidine (MIBG) was prepared, such that upon labeling, the desired product was formed with concomitant release of the fluorous group. The desired product was then readily separated from the starting material and fluorous by-products by chemoselective filtration using a fluorous solid-phase extraction cartridge. Results: High purity [{sup 125}I]- and [{sup 123}I]MIBG were produced in 81{+-}3% and 80% radiochemical yield respectively in less than 20 min without high-performance liquid chromatography (HPLC) purification. The purified product contained less than 1 ppm tin as determined by inductively coupled plasma-mass spectrometry (ICP-MS). Conclusions: A convenient, solution-phase method to produce radioiodinated MIBG in high effective specific activity without employing preparative HPLC was developed. Using the reported approach, a kit for the production of {sup 123}I- and {sup 125}I-MIBG is feasible and is currently being developed.

  3. A Chernobyl lesson for aerial monitoring: integration of passive measurements with active sampling in the emergency early phase

    International Nuclear Information System (INIS)

    In our experience, the first quantitative measurement of a contamination parameter has been only possible after many days from the beginning of the accident. Indeed with aerial monitoring systems in use, the quantification of the source activity, or the ground contamination, through the analysis of the gamma ray spectra measured, is only possible with the assumption of a source pattern (localized for a point-like source, diffused for ground surface contamination). In case of a more complex situation, there is not a suitable knowledge to model the radiation source; therefore the measurements can only supply qualitative information. This is the case, both in near and far field, when the radioactive plume released by an accident is passing over the country. The lack of quantitative measurements and the derived uncertainty in forecasting the propagation of the radioactive contamination, does not help the emergency management in the most critical phase, i.e. when countermeasures have to be decided in a preventive way and some risk of negative effects is inevitably linked to their enforcement. A different tool for the emergency management should be provided. An aerial platform instrumented for in-plume measurements, aiming to characterize the extension, composition and concentration of the radioactive mixture in the plume, as well as to measure in situ meteorological parameters could be of invaluable help in the emergency early phase. During last years research and manufacturing activities have been developed to reach these goals. (authors)

  4. Temporal phasing of locomotor activity, heart rate rhythmicity, and core body temperature is disrupted in VIP receptor 2-deficient mice.

    Science.gov (United States)

    Hannibal, Jens; Hsiung, Hansen M; Fahrenkrug, Jan

    2011-03-01

    Neurons of the brain's biological clock located in the hypothalamic suprachiasmatic nucleus (SCN) generate circadian rhythms of physiology (core body temperature, hormone secretion, locomotor activity, sleep/wake, and heart rate) with distinct temporal phasing when entrained by the light/dark (LD) cycle. The neuropeptide vasoactive intestinal polypetide (VIP) and its receptor (VPAC2) are highly expressed in the SCN. Recent studies indicate that VIPergic signaling plays an essential role in the maintenance of ongoing circadian rhythmicity by synchronizing SCN cells and by maintaining rhythmicity within individual neurons. To further increase the understanding of the role of VPAC2 signaling in circadian regulation, we implanted telemetric devices and simultaneously measured core body temperature, spontaneous activity, and heart rate in a strain of VPAC2-deficient mice and compared these observations with observations made from mice examined by wheel-running activity. The study demonstrates that VPAC2 signaling is necessary for a functional circadian clock driving locomotor activity, core body temperature, and heart rate rhythmicity, since VPAC2-deficient mice lose the rhythms in all three parameters when placed under constant conditions (of either light or darkness). Furthermore, although 24-h rhythms for three parameters are retained in VPAC2-deficient mice during the LD cycle, the temperature rhythm displays markedly altered time course and profile, rising earlier and peaking ∼4-6 h prior to that of wild-type mice. The use of telemetric devices to measure circadian locomotor activity, temperature, and heart rate, together with the classical determination of circadian rhythms of wheel-running activity, raises questions about how representative wheel-running activity may be of other behavioral parameters, especially when animals have altered circadian phenotype.

  5. Venus Phasing.

    Science.gov (United States)

    Riddle, Bob

    1997-01-01

    Presents a science activity designed to introduce students to the geocentric and heliocentric models of the universe. Helps students discover why phase changes on Venus knocked Earth out of the center of the universe. (DKM)

  6. Linking Soil Microbial Activity to Water- and Air-Phase Contents and Diffusivities

    OpenAIRE

    Schjønning, P.; I. K. Thomsen; P. Moldrup; B. T. Christensen

    2003-01-01

    Quantification of in situ soil microbial activity is indispensable in order to improve manipulation of nutrient turnover in soil and optimize crop nutrient supply. We sampled 100 cm3 cores of undisturbed arable soil at three locations along a naturally occurring clay gradient (L1: 11% clay; L3: 22% clay; L5: 34 % clay). The cores were drained to seven different matric potentials in the range –15 to –1500 hPa and gas diffusion determined prior to a 4 week incubation at 20oC in the dark. For al...

  7. Stability Improvements of an LCL-filter based Three-phase Active Rectifier

    DEFF Research Database (Denmark)

    Liserre, Marco; Dell'Aquila, Antonio; Blaabjerg, Frede

    2002-01-01

    for the ac inductors making them expensive and bulky. Moreover the dynamic of the system becomes poor with so high value of inductance. On the contrary to adopt an LCL-filter configuration allows to use reduced values of the inductances (preserving dynamic) and to reduce the switching frequency pollution......, both passive (based on the use of resistors) and active (based on the modification of the control algorithm), is studied using the z-plane root locus approach and looking to dynamic performances and losses. In fact it is necessary to verify the dynamic effects by the introduction of damping resistors...

  8. A unified active damping control for single-phase differential buck inverter with LCL-filter

    DEFF Research Database (Denmark)

    Yao, Wenli; Wang, Xiongfei; Zhang, Xiaobin;

    2015-01-01

    control of a grid-connected differential mode buck inverter with an LCL filter. A generalized small-signal model of the inverter is built first with the averaged switching model. It is shown that the LCL filter resonance merely occurs in the differential mode, while an LC filter resonance exists in the...... common mode, provided that the filter parameters of the two bridges are kept the same. A unified active damping control approach is then proposed for stabilizing the inverter and improving the transient performance under a wide range of grid impedance. Lastly, experimental tests are carried out and the...

  9. Thermal activation analysis of the structural and phase transformations in the Zr-Cu-Nb amorphous alloy

    Directory of Open Access Journals (Sweden)

    Fedotova N.L.

    2011-05-01

    Full Text Available In the present work, the procedure of the estimation of the thermal activation parameters from the data of dilatometric measurements and the results of its application to the Zr-Cu-Nb amorphous alloy discussed. The determination of the thermal activation parameters of the processes occurring in materials under known temperature-force conditions can be useful for the identification of the structural mechanisms of phase transformations and the evolution of defect structure. We used the data of dilatometric measurements for evaluating the effective activation energy. This method exhibits some advantages over the conventional one due to the design features of dilatometers. First, it ensures the precise measurement of strains; second, the assigned temperature regime is very precisely maintained both at the stage of heating and upon isothermal holding; third, it ensures a high-speed continuous record of the experimental data. The developed method of evaluating the effective activation energy from the results of dilatometric experiments provides statistically reliable results. The data of the photometric analysis of structure images are in accordance with the results of dilatometric experiments

  10. Liquid phase adsorption of Crystal violet onto activated carbons derived from male flowers of coconut tree.

    Science.gov (United States)

    Senthilkumaar, S; Kalaamani, P; Subburaam, C V

    2006-08-25

    Adsorption of Crystal violet, a basic dye onto phosphoric and sulphuric acid activated carbons (PAAC and SAAC), prepared from male flowers coconut tree has been investigated. Equilibrium data were successfully applied to study the kinetics and mechanism of adsorption of dye onto both the carbons. The kinetics of adsorption was found to be pseudo second order with regard to intraparticle diffusion. The pseudo second order is further supported by the Elovich model, which in turn intensifies the fact of chemisorption of dye onto both the carbons. Quantitative removal of dye at higher initial pH of dye solution reveals the basic nature of the Crystal violet and acidic nature of the activated carbons. Influence of temperature on the removal of dye from aqueous solution shows the feasibility of adsorption and its endothermic nature. Mass transfer studies were also carried out. The adsorption capacities of both the carbons were found to be 60.42 and 85.84 mg/g for PAAC and SAAC, respectively. Langmuir's isotherm data were used to design single-stage batch adsorption model.

  11. Activity-dependent synaptic plasticity modulates the critical phase of brain development.

    Science.gov (United States)

    Chaudhury, Sraboni; Sharma, Vikram; Kumar, Vivek; Nag, Tapas C; Wadhwa, Shashi

    2016-04-01

    Plasticity or neuronal plasticity is a unique and adaptive feature of nervous system which allows neurons to reorganize their interactions in response to an intrinsic or extrinsic stimulation and shapes the formation and maintenance of a functional neuronal circuit. Synaptic plasticity is the most important form of neural plasticity and plays critical role during the development allowing the formation of precise neural connectivity via the process of pruning. In the sensory systems-auditory and visual, this process is heavily dependent on the external cues perceived during the development. Environmental enrichment paradigms in an activity-dependent manner result in early maturation of the synapses and more efficient trans-synaptic signaling or communication flow. This has been extensively observed in the avian auditory system. On the other hand, stimuli results in negative effect can cause alterations in the synaptic connectivity and strength resulting in various developmental brain disorders including autism, fragile X syndrome and rett syndrome. In this review we discuss the role of different forms of activity (spontaneous or environmental) during the development of the nervous system in modifying synaptic plasticity necessary for shaping the adult brain. Also, we try to explore various factors (molecular, genetic and epigenetic) involved in altering the synaptic plasticity in positive and negative way. PMID:26515724

  12. Performance enhancement of the single-phase series active filter by employing the load voltage waveform reconstruction and line current sampling delay reduction methods

    DEFF Research Database (Denmark)

    Senturk, O.S.; Hava, A.M.

    2011-01-01

    This paper proposes the waveform reconstruction method (WRM), which is utilized in the single-phase series active filter's (SAF's) control algorithm, in order to extract the load harmonic voltage component of voltage harmonic type single-phase diode rectifier loads. Employing WRM and the line...... current sampling delay reduction method, a single-phase SAF compensated system provides higher harmonic isolation performance and higher stability margins compared to the system using conventional synchronous-reference-frame-based methods. The analytical, simulation, and experimental studies of a 2.5 k......W single-phase SAF compensated system prove the theory....

  13. [Synergetic Inhibitory Effect of Free Ammonia and Aeration Phase Length Control on the Activity of Nitrifying Bacteria].

    Science.gov (United States)

    Sun, Hong-wei; Lü, Xin-tao; Wei, Xue-fen; Zhao, Hua-nan; Ma, Juan; Fang, Xiao-hang

    2016-03-15

    Three sequencing batch reactors (SBRs) labeled with R(Ahead), R(Exact) and R(Exceed) were employed to investigate the synergetic inhibition effect of free ammonia (FA) and length of aeration phase on the activity of ammonia-oxidizing bacteria ( AOB) and nitrite- oxidizing bacteria (NOB) after shortcut nitritation was achieved in the systems. The experiments were conducted under the conditions of three FA concentrations (0.5, 5. 1, 10.1 mg · L⁻¹) combined with three kinds of aeration time (t(Exact): the time when ammonia oxidation was completed; t(Ahead): 30 min ahead of the time when ammonia oxidation was completed; t(Exceed): 30 min exceeded when the time ammonia oxidation was completed). It was found that short-cut nitrification could be successfully established in three reactors with a FA level of 10.1 mg · L⁻¹. Meanwhile, the speed of achieving nitritation was in the sequence of R(Ahead) > R(Exact) > R(Exceed) with operational cycles of 56, 62 and 72, respectively. Compared to AOB, NOB in the three reactors was observed to be more sensitive to FA, resulting in AOB activity higher than NOB activity throughout the whole experimental period. Moreover, there was great difference in the activity coefficient ( η) between AOB and NOB. The activity coefficients of AOB were in the order of η(RExact) > η(RExceed) > η(RAhead) with the values of 104.4%, 100% and 85.8%, respectively. Nevertheless, the activity coefficients of NOB were in the order of η(RExceed) > η(RExact) > η(RAhead) with the values of 71.2%, 64.9% and 50.2%, respectively.

  14. [Synergetic Inhibitory Effect of Free Ammonia and Aeration Phase Length Control on the Activity of Nitrifying Bacteria].

    Science.gov (United States)

    Sun, Hong-wei; Lü, Xin-tao; Wei, Xue-fen; Zhao, Hua-nan; Ma, Juan; Fang, Xiao-hang

    2016-03-15

    Three sequencing batch reactors (SBRs) labeled with R(Ahead), R(Exact) and R(Exceed) were employed to investigate the synergetic inhibition effect of free ammonia (FA) and length of aeration phase on the activity of ammonia-oxidizing bacteria ( AOB) and nitrite- oxidizing bacteria (NOB) after shortcut nitritation was achieved in the systems. The experiments were conducted under the conditions of three FA concentrations (0.5, 5. 1, 10.1 mg · L⁻¹) combined with three kinds of aeration time (t(Exact): the time when ammonia oxidation was completed; t(Ahead): 30 min ahead of the time when ammonia oxidation was completed; t(Exceed): 30 min exceeded when the time ammonia oxidation was completed). It was found that short-cut nitrification could be successfully established in three reactors with a FA level of 10.1 mg · L⁻¹. Meanwhile, the speed of achieving nitritation was in the sequence of R(Ahead) > R(Exact) > R(Exceed) with operational cycles of 56, 62 and 72, respectively. Compared to AOB, NOB in the three reactors was observed to be more sensitive to FA, resulting in AOB activity higher than NOB activity throughout the whole experimental period. Moreover, there was great difference in the activity coefficient ( η) between AOB and NOB. The activity coefficients of AOB were in the order of η(RExact) > η(RExceed) > η(RAhead) with the values of 104.4%, 100% and 85.8%, respectively. Nevertheless, the activity coefficients of NOB were in the order of η(RExceed) > η(RExact) > η(RAhead) with the values of 71.2%, 64.9% and 50.2%, respectively. PMID:27337903

  15. Active ultrasonic cross-correlation flowmeters for mixed-phase pipe flows

    Science.gov (United States)

    Sheen, S. H.; Raptis, A. C.

    Two ultrasonic flowmeters which employ the active cross-correlation technique and use a simple clamp-on transducer arrangement are discussed. The flowmeter for solid/liquid flows was tested over a wide range of coal concentration in water and oil. The measured velocity based on the peak position of the cross-correlation function is consistently higher by about 15% than the average velocity measured by flow diversion. The origin of the difference results mainly from the flow velocity profiles and the transit-time probability distribution. The flowmeter that can measure particle velocity in a solid/gas flow requires acoustic decoupling arrangement between two sensing stations. The measured velocity is mainly associated with the particles near the wall. Performance of both flowmeters is presented.

  16. Effects of Curcuma xanthorrhiza extracts and their constituents on phase ii drug-metabolizing enzymes activity

    Directory of Open Access Journals (Sweden)

    Nurul Afifah Mohd Salleh

    2016-01-01

    Full Text Available Background: Curcuma xanthorrhiza is a native Indonesian plant and traditionally utilized for a range of illness including liver damage, hypertension, diabetes, and cancer. Objective: The study determined the effects of C. xanthorrhiza extracts (ethanol and aqueous and their constituents (curcumene and xanthorrhizol on UDP-glucuronosyltransferase (UGT and glutathione transferase (GST activities. Materials and Methods: The inhibition studies were evaluated both in rat liver microsomes and in human recombinant UGT1A1 and UGT2B7 enzymes. p-nitrophenol and beetle luciferin were used as the probe substrates for UGT assay while 1-chloro-2,4-dinitrobenzene as the probe for GST assay. The concentrations of extracts studied ranged from 0.1 to 1000 μg/mL while for constituents ranged from 0.01 to 500 μM. Results: In rat liver microsomes, UGT activity was inhibited by the ethanol extract (IC50 =279.74 ± 16.33 μg/mL. Both UGT1A1 and UGT2B7 were inhibited by the ethanol and aqueous extracts with IC50values ranging between 9.59–22.76 μg/mL and 110.71–526.65 μg/Ml, respectively. Rat liver GST and human GST Pi-1 were inhibited by ethanol and aqueous extracts, respectively (IC50 =255.00 ± 13.06 μg/mL and 580.80 ± 18.56 μg/mL. Xanthorrhizol was the better inhibitor of UGT1A1 (IC50 11.30 ± 0.27 μM as compared to UGT2B7 while curcumene did not show any inhibition. For GST, both constituents did not show any inhibition. Conclusion: These findings suggest that C. xanthorrhiza have the potential to cause herb-drug interaction with drugs that are primarily metabolized by UGT and GST enzymes.

  17. Generation of Multiple Fluid-Phase C3b:Plasma Protein Complexes During Complement Activation. Possible Implications in C3 Glomerulopathies

    OpenAIRE

    Ramadass, Mahalakshmi; Ghebrehiwet, Berhane; Richard J. Smith; Kew, Richard R.

    2013-01-01

    The complement system is tightly regulated to safeguard against tissue damage that results from unwanted activation. The key step of C3 cleavage to C3b is regulated by multiple mechanisms that control the initiation and extent of activation. This study demonstrated that C3b:plasma protein complexes form in the fluid-phase during complement activation. Several different plasma proteins displayed a discrete high molecular SDS-resistant band when any of the three complement activating pathways w...

  18. Phase transformation of ZrO{sub 2}:Tb{sup 3+} nanophosphor: Color tunable photoluminescence and photocatalytic activities

    Energy Technology Data Exchange (ETDEWEB)

    Vidya, Y.S., E-mail: vidyays.phy@gmail.com [Department of Physics, Lal Bahadur Shastri Government First Grade College, Bangalore 560 032 (India); Gurushantha, K. [Research Centre, Department of Science, East West Institute of Technology, Bangalore 560 091 (India); Nagabhushana, H. [Prof. C.N.R. Rao Centre for Advanced Materials, Tumkur University, Tumkur 572 103 (India); Sharma, S.C. [Vice Chancellor, Chhattisgarh Swami Vivekananda Technical University, North Park Avenue, Sector-8, Bhilai, Chhattisgarh 490 009 (India); Anantharaju, K.S., E-mail: ananth.che@gmail.com [Research Centre, Department of Science, East West Institute of Technology, Bangalore 560 091 (India); Shivakumara, C. [Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012 (India); Suresh, D. [Prof. C.N.R. Rao Centre for Advanced Materials, Tumkur University, Tumkur 572 103 (India); Nagaswarupa, H.P.; Prashantha, S.C.; Anilkumar, M.R. [Research Centre, Department of Science, East West Institute of Technology, Bangalore 560 091 (India)

    2015-02-15

    Highlights: • ZrO{sub 2}:Tb{sup 3+} nanophosphors were synthesized by low temperature combustion method. • The crystal structure changes from tetragonal to cubic symmetry. • CIE chromaticity coordinates gets tuned from pale green to warm white. • It may find potential applications in luminescence devices especially in WLED’s. • Superior photocatalytic activity was observed for ZrO{sub 2}:Tb{sup 3+} (7 mol%) photocatalyst. - Abstract: The current study involves synthesis of a series of Tb{sup 3+} doped ZrO{sub 2} nanophosphors by solution combustion method using oxalyl dihydrazide as fuel. The as-formed ZrO{sub 2}:Tb{sup 3+} nanophosphors having different concentrations of Tb{sup 3+} (1-11 mol%) were characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV-Visible spectroscopic techniques and the materials were subjected to photoluminescence and photocatalytic dye decolorization studies. The PXRD analysis indicates the formation of tetragonal symmetry up to 5 mol% concentration of Tb{sup 3+}. Further increase in Tb{sup 3+} concentration has lead to cubic phase formation and the same was confirmed by Rietveld refinement analysis. SEM images revealed that material was highly porous in nature comprising of large voids and cracks with irregular morphology. TEM and SAED images clearly confirm the formation of high quality tetragonal nanocrystals. The emissive properties of nanophosphors were found to be dependent on Tb{sup 3+} dopant concentration. The green emission of the material was turned to white emission with the increase of Tb{sup 3+} ion concentration. The photocatalytic activities of these nanophosphors were probed for the decolorization of Congo red under UV and Sunlight irradiation. All the photocatalysts showed enhanced activity under UV light compared to Sunlight. The photocatalyst with 7 mol% Tb{sup 3+} showed enhanced activity attributed to effective separation of

  19. The value of Tc-99m MIBI scintigraphy in active disease and remission phase of multiple myeloma

    International Nuclear Information System (INIS)

    Background: 99m Tc methoxy isobutyl isonitrile (99m Tc -MIBI)has been proposed as a tumor seeking agent in malignant disease. The goal of this study is to evaluate the frequency distribution of the different patterns, intensity and extension of abnormal uptake identified in MIBI scan in relation with various clinical status of the patients diagnosed as a multiple myeloma. Methods: forty-three patients entered the study, including six patients with no prior treatment , 22 patients who received autologous bone morrow graft, and 15 patients with history of chemotherapy and radiotherapy. Plasma protein electrophoresis for monoclonal antibody, bone morrow biopsy and urine analysis for Bence-Jones protein has been carried out and standard criteria were used for diagnosis of active disease and remission phase for each patients. The extension of each lesion(E-score) on scintigraphy were categorized into E0-E3 by three nuclear physicians who were blinded to the patient's clinical condition. I-score was also obtained with comparing the intensity of the lesions with intensity of myocardial uptake and classified as I0-I3. Results: the sensitivity, specificity, positive predictive value and negative predictive value of 99m Tc -MIBI scan for determining active lesions and released cases were 69%, 100%, 100% and 60%, respectively. Nineteen patients were initially thought to be in remission phase, but scintigraphy was abnormal in 5 cases who were diagnosed as active myeloma later in the course of the study. There was a significant correlation between clinical status and pattern, intensity and extension of the abnormal uptake of 99m Tc -MIBI. Also a significant correlation between intensity and extension of the abnormal tracer uptake with serum monoclonal component and urine Bence-Jones protein was noted, however no correlation between blood hemo globulin and degree of extension in scintigraphy was seen. Conclusion: Our study suggests the pattern, extension and intensity of 99m Tc

  20. Pseudomonas corrugata crpCDE is part of the cyclic lipopeptide corpeptin biosynthetic gene cluster and is involved in bacterial virulence in tomato and in hypersensitive response in Nicotiana benthamiana

    NARCIS (Netherlands)

    Strano, C.P.; Bella, P.; Licciardello, G.; Fiore, A.; Piero, Lo A.R.; Fogliano, V.; Fogliano, V.; Catara, V.

    2015-01-01

    Pseudomonas corrugata CFBP 5454 produces two kinds of cyclic lipopeptides (CLPs), cormycin A and corpeptins, both of which possess surfactant, antimicrobial and phytotoxic activities. In this study, we identified genes coding for a putative non-ribosomal peptide synthetase and an ABC-type transport

  1. Bactericidal and Fungicidal Activity in the Gas Phase of Sodium Dichloroisocyanurate (NaDCC).

    Science.gov (United States)

    Proto, Antonio; Zarrella, Ilaria; Cucciniello, Raffaele; Pironti, Concetta; De Caro, Francesco; Motta, Oriana

    2016-08-01

    Sodium dichloroisocyanurate (NaDCC) is usually employed as a disinfectant for the treatment of water, environmental surfaces and medical equipment principally for its effectiveness as a microbicide agent. In this study, we explore the possibility of a new use for NaDCC by investigating the microbicidal activity of chlorine, which derives from the hydrolysis of NaDCC mediated by air humidity, and by testing its effect on the neutralization of microbes present in domestic waste. NaDCC was inserted in a plastic garbage can where LB agar plates, with different dilutions of a known title of four different microorganisms (Escherichia coli, Staphylococcus aureus, Debaryomyces hansenii and Aspergillus brasiliensis), were weakly inserted. The molecular chlorine (Cl2) levels present in the garbage can were quantified using an iodometric titration. The gas emitted in the garbage can presented a strong microbicide effect, inhibiting the proliferation of all four microorganisms and for four consecutive weeks, thus showing that NaDCC hydrolysis, mediated by air humidity, is able to ensure the decontamination of restricted environments, avoiding the proliferation of both Gram-positive and Gram-negative bacteria as well as fungi. PMID:27086304

  2. The Contribution of the Activation Entropy to the Gas-Phase Stability of Modified Nucleic Acid Duplexes

    Science.gov (United States)

    Hari, Yvonne; Dugovič, Branislav; Istrate, Alena; Fignolé, Annabel; Leumann, Christian J.; Schürch, Stefan

    2016-07-01

    Tricyclo-DNA (tcDNA) is a sugar-modified analogue of DNA currently tested for the treatment of Duchenne muscular dystrophy in an antisense approach. Tandem mass spectrometry plays a key role in modern medical diagnostics and has become a widespread technique for the structure elucidation and quantification of antisense oligonucleotides. Herein, mechanistic aspects of the fragmentation of tcDNA are discussed, which lay the basis for reliable sequencing and quantification of the antisense oligonucleotide. Excellent selectivity of tcDNA for complementary RNA is demonstrated in direct competition experiments. Moreover, the kinetic stability and fragmentation pattern of matched and mismatched tcDNA heteroduplexes were investigated and compared with non-modified DNA and RNA duplexes. Although the separation of the constituting strands is the entropy-favored fragmentation pathway of all nucleic acid duplexes, it was found to be only a minor pathway of tcDNA duplexes. The modified hybrid duplexes preferentially undergo neutral base loss and backbone cleavage. This difference is due to the low activation entropy for the strand dissociation of modified duplexes that arises from the conformational constraint of the tc-sugar-moiety. The low activation entropy results in a relatively high free activation enthalpy for the dissociation comparable to the free activation enthalpy of the alternative reaction pathway, the release of a nucleobase. The gas-phase behavior of tcDNA duplexes illustrates the impact of the activation entropy on the fragmentation kinetics and suggests that tandem mass spectrometric experiments are not suited to determine the relative stability of different types of nucleic acid duplexes.

  3. Preparation and antibacterial activity of Ag–TiO2 composite film by liquid phase deposition (LPD) method

    Indian Academy of Sciences (India)

    S-Q Sun; B Sun; Wenqin Zhang; D Wang

    2008-02-01

    A liquid phase deposition (LPD) method has been devised for the deposition of Ag–TiO2 thin films on ceramic tiles with glazed surface at a low temperature. The Ag–TiO2 thin films obtained were welladhered, homogenous and coloured by interference of reflected light. The films were characterized by X-ray diffraction and scanning electron microscopy. From these analyses, it was found that silver ions were trapped in TiO2 matrix and their reduction could be achieved at 600°C annealing temperature. The antibacterial activity against S. aureus and . coli has been studied applying the so called antibacterial-drop test. The Ag–TiO2 thin films exhibited a high antibacterial activity. AAS was used for the quantitave determination of silver ion concentration releasing from the Ag–TiO2 thin film. The releasing rate of silver ions from the Ag–TiO2 film was 0.118 g/ml during 192 h. The antibacterial effect of Ag–TiO2 thin film before and after aging in a weathering chamber for 48 h was compared and the results show that the antibacterial activity is not compromised after weathering.

  4. Design and Analysis of Sliding Mode Controller and Simplified Space Vector Modulation for Three Phase Shunt Active Power Filter

    Directory of Open Access Journals (Sweden)

    S. Elangovan

    2014-07-01

    Full Text Available The main aim of this study is to control a multivariable coupled system by choosing sliding mode switching function. A Sliding mode control approach is developed to control a three phase three wire voltage source inverter operating as a shunt active power filter. Hence, no need to divide the system model developed in the synchronous ‘dq’ reference frame into two separate loops. Furthermore, the proposed control strategy allows a better stability and robustness over a wide range of operation. When sine PWM is used for generation of pulses for the switches, a variable switching nature is exhibited. The pulses for the active filter are fed by a Space Vector Modulation in order to have a constant switching of converter switches. But, the conventional space vector modulation, if implemented practically, needs a complicated algorithm which uses the trigonometric functions such as arctan, Sine and Cosine functions which in turn needs look up tables to store the pre-calculated trigonometric values. In this study, a very simplified algorithm is proposed for generating Space vector modulated pulse for all six switches without the use of look up tables and only by sensing the voltages and currents of the voltage source inverter acting as shunt active filter. The simulation using PSIM and MATLAB software verifies the results very well.

  5. Development of in vivo biotransformation enzyme assays for ecotoxicity screening: In vivo measurement of phases I and II enzyme activities in freshwater planarians.

    Science.gov (United States)

    Li, Mei-Hui

    2016-08-01

    The development of a high-throughput tool is required for screening of environmental pollutants and assessing their impacts on aquatic animals. Freshwater planarians can be used in rapid and sensitive toxicity bioassays. Planarians are known for their remarkable regeneration ability but much less known for their metabolic and xenobiotic biotransformation abilities. In this study, the activities of different phase I and II enzymes were determined in vivo by directly measuring fluorescent enzyme substrate disappearance or fluorescent enzyme metabolite production in planarian culture media. For phase I enzyme activity, O-deethylation activities with alkoxyresorufin could not be detected in planarian culture media. By contrast, O-deethylation activities with alkoxycoumarin were detected in planarian culture media. Increases in 7-ethoxycoumarin O-deethylase (ECOD) activities was only observed in planarians exposed to 1μM, but not 10μM, β-naphthoflavone for 24h. ECOD activity was inhibited in planarians exposed to 10 and 100μM rifampicin or carbamazepine for 24h. For phase II enzyme activity, DT-diaphorase, arylsulfatases, uridine 5'-diphospho (UDP)-glucuronosyltransferase or catechol-O-methyltransferase activity was determined in culture media containing planarians. The results of this study indicate that freshwater planarians are a promising model organism to monitor exposure to environmental pollutants or assess their impacts through the in vivo measurement of phase I and II enzyme activities. PMID:27062342

  6. Effects of Curcuma xanthorrhiza Extracts and Their Constituents on Phase II Drug-metabolizing Enzymes Activity

    Science.gov (United States)

    Salleh, Nurul Afifah Mohd; Ismail, Sabariah; Ab Halim, Mohd Rohaimi

    2016-01-01

    Background: Curcuma xanthorrhiza is a native Indonesian plant and traditionally utilized for a range of illness including liver damage, hypertension, diabetes, and cancer. Objective: The study determined the effects of C. xanthorrhiza extracts (ethanol and aqueous) and their constituents (curcumene and xanthorrhizol) on UDP-glucuronosyltransferase (UGT) and glutathione transferase (GST) activities. Materials and Methods: The inhibition studies were evaluated both in rat liver microsomes and in human recombinant UGT1A1 and UGT2B7 enzymes. p-nitrophenol and beetle luciferin were used as the probe substrates for UGT assay while 1-chloro-2,4-dinitrobenzene as the probe for GST assay. The concentrations of extracts studied ranged from 0.1 to 1000 μg/mL while for constituents ranged from 0.01 to 500 μM. Results: In rat liver microsomes, UGT activity was inhibited by the ethanol extract (IC50 =279.74 ± 16.33 μg/mL). Both UGT1A1 and UGT2B7 were inhibited by the ethanol and aqueous extracts with IC50 values ranging between 9.59–22.76 μg/mL and 110.71–526.65 μg/Ml, respectively. Rat liver GST and human GST Pi-1 were inhibited by ethanol and aqueous extracts, respectively (IC50 =255.00 ± 13.06 μg/mL and 580.80 ± 18.56 μg/mL). Xanthorrhizol was the better inhibitor of UGT1A1 (IC50 11.30 ± 0.27 μM) as compared to UGT2B7 while curcumene did not show any inhibition. For GST, both constituents did not show any inhibition. Conclusion: These findings suggest that C. xanthorrhiza have the potential to cause herb-drug interaction with drugs that are primarily metabolized by UGT and GST enzymes. SUMMARY Findings from this study would suggest which of Curcuma xanthorrhiza extracts and constituents that would have potential interactions with drugs which are highly metabolized by UGT and GST enzymes. Further clinical studies can then be designed if needed to evaluate the in vivo pharmacokinetic relevance of these interactions Abbreviations Used: BSA: Bovine serum albumin

  7. Role of active galactic nuclei in the luminous infrared galaxy phase at z ≤ 3

    Science.gov (United States)

    Lin, Ming-Yi; Hashimoto, Yasuhiro; Foucaud, Sébastien

    2016-03-01

    To understand the interactions between active galactic nuclei (AGNs) and star formation during the evolution of galaxies, we investigate 142 galaxies detected in both X-ray and 70 μm observations in the COSMOS (Cosmic Evolution Survey) field. All of our data are obtained from the archive X-ray point-source catalogues from Chandra and XMM-Newton observations, and the far-infrared 70 μm point-source catalogue from Spitzer-MIPS observations. Although the IRAC [3.6 μm]-[4.5 μm] versus [5.8 μm]-[8.0 μm] colours of our sample indicate that only ˜63 per cent of our sources would be classified as AGNs, the ratio of the rest-frame 2-10 keV luminosity to the total infrared luminosity (8-1000 μm) shows that the entire sample has comparatively higher X-ray luminosity than that expected from pure star-forming galaxies, suggesting the presence of an AGN in all of our sources. From an analysis of the X-ray hardness ratio, we find that sources with both 70 μm and X-ray detection tend to have a higher hardness ratio relative to the whole X-ray-selected source population, suggesting the presence of more X-ray absorption in the 70 μm detected sources. In addition, we find that the observed far-infrared colours of 70 μm detected sources with and without X-ray emission are similar, suggesting the far-infrared emission could be mainly powered by star formation.

  8. Study of multi-layer active magnetic regenerators using magnetocaloric materials with first and second order phase transition

    Science.gov (United States)

    Lei, T.; Engelbrecht, K.; Nielsen, K. K.; Neves Bez, H.; Bahl, C. R. H.

    2016-09-01

    Magnetocaloric materials (MCM) with a first order phase transition (FOPT) usually exhibit a large, although sharp, isothermal entropy change near their Curie temperature, compared to materials with a second order phase transition (SOPT). Experimental results of applying FOPT materials in recent magnetocaloric refrigerators (MCR) demonstrated the great potential for these materials, but a thorough study on the impact of the moderate adiabatic temperature change and strong temperature dependence of the magnetocaloric effect (MCE) is lacking. Besides, comparing active magnetic regenerators (AMR) using FOPT and SOPT materials is also of fundamental interest. We present modeling results of multi-layer AMRs using FOPT and SOPT materials based on a 1D numerical model. First the impact of isothermal entropy change, adiabatic temperature change and shape factor describing the temperature dependence of the MCE are quantified and analyzed by using artificially built magnetocaloric properties. Then, based on measured magnetocaloric properties of La(Fe,Mn,Si)13H y and Gd, an investigation on how to layer typical FOPT and SOPT materials with different temperature spans is carried out. Moreover, the sensitivity of variation in Curie temperature distribution for both groups of AMRs is investigated. Finally, a concept of mixing FOPT and SOPT materials is studied for improving the stability of layered AMRs with existing materials.

  9. Characterization and photocatalytic activity of boron-doped TiO2 thin films prepared by liquid phase deposition technique

    Indian Academy of Sciences (India)

    Noor Shahina Begum; H M Farveez Ahmed; O M Hussain

    2008-10-01

    Boron doped TiO2 thin films have been successfully deposited on glass substrate and silicon wafer at 30°C from an aqueous solution of ammonium hexa-fluoro titanate and boron trifluoride by liquid phase deposition technique. The boric acid was used as an – scavenger. The resultant films were characterized by XRD, EDAX, UV and microstructures by SEM. The result shows the deposited film to be amorphous which becomes crystalline between 400 and 500°C. The EDAX and XRD data confirm the existence of boron atom in TiO2 matrix and a small peak corresponding to rutile phase was also found. Boron doped TiO2 thin films can be used as photocatalyst for the photodegradation of chlorobenzene which is a great environmental hazard. It was found that chlorobenzene undergoes degradation efficiently in presence of boron doped TiO2 thin films by exposing its aqueous solution to visible light. The photocatalytic activity increases with increase in the concentration of boron.

  10. Muscle activity during stance phase of walking: Comparison of males with transfemoral amputation with osseointegrated fixations to nondisabled male volunteers

    Directory of Open Access Journals (Sweden)

    Annette Pantall, DO(UK, PhD

    2013-07-01

    Full Text Available A recent development in prosthetics is the osseointegrated fixation (OF, with improvements in comfort, fatigue, hip movement, and ease of prosthetic attachment reported. However, little information is available regarding muscle function. This study reports on selected gait parameters of the residual limb during the stance phase of level overground walking, focusing on muscle activity. Five males with transfemoral amputation (TFA with OFs were recruited. Ground reaction force (GRF, lower-limb kinematics, and surface electromyography (sEMG from residual-limb muscles were recorded. sEMG data were also collected from a group of 10 nondisabled male subjects. Interstance variability of gait parameters was assessed by coefficient of multiple correlations. Repeatability of GRF and hip kinematics was high, whereas repeatability of the sEMG was low for four of the five individuals with TFA. Interstance variability of the sEMG for gluteus medius (GMED was significantly greater in the group with TFA. The main difference in sEMG between the groups was the phase, with GMED and adductor magnus displaying greater differences than their counterparts in the nondisabled group. Results demonstrate that muscles in the residual limb retain aspects of their previous functional pattern.

  11. Muscle activity during stance phase of walking: comparison of males with transfemoral amputation with osseointegrated fixations to nondisabled male volunteers.

    Science.gov (United States)

    Pantall, Annette; Ewins, David

    2013-01-01

    A recent development in prosthetics is the osseointegrated fixation (OF), with improvements in comfort, fatigue, hip movement, and ease of prosthetic attachment reported. However, little information is available regarding muscle function. This study reports on selected gait parameters of the residual limb during the stance phase of level overground walking, focusing on muscle activity. Five males with transfemoral amputation (TFA) with OFs were recruited. Ground reaction force (GRF), lower-limb kinematics, and surface electromyography (sEMG) from residual-limb muscles were recorded. sEMG data were also collected from a group of 10 nondisabled male subjects. Interstance variability of gait parameters was assessed by coefficient of multiple correlations. Repeatability of GRF and hip kinematics was high, whereas repeatability of the sEMG was low for four of the five individuals with TFA. Interstance variability of the sEMG for gluteus medius (GMED) was significantly greater in the group with TFA. The main difference in sEMG between the groups was the phase, with GMED and adductor magnus displaying greater differences than their counterparts in the nondisabled group. Results demonstrate that muscles in the residual limb retain aspects of their previous functional pattern.

  12. Phase transitions and steady-state microstructures in a two-temperature lattice-gas model with mobile active impurities

    DEFF Research Database (Denmark)

    Henriksen, Jonas Rosager; Sabra, Mads Christian; Mouritsen, Ole G.

    2000-01-01

    . The properties of the model are calculated by Monte Carlo computer-simulation techniques. The two temperatures and the external drive on the system lead to a rich phase diagram including regions of microstructured phases in addition to macroscopically ordered (phase-separated) and disordered phases...

  13. A Repetitive Control Scheme Aimed at Compensating the 6k + 1 Harmonics for a Three-Phase Hybrid Active Filter

    DEFF Research Database (Denmark)

    Luo, Zhaoxu; Su, Mei; Yang, Jian;

    2016-01-01

    is reduced, and the possibility of amplifying and even injecting any harmonic noises into the system is avoided to a great extent. Moreover, the proposed repetitive scheme is used in the control of a three-phase hybrid active power filter. The experimental results validate the effectiveness of the proposed......The traditional repetitive controller has relatively worse stability and poor transient performance because it generates infinite gain at all the integer multiples of the fundamental frequency, and its control action is postponed by one fundamental period (T0). To improve these disadvantages, many...... repetitive controllers with reduced delay time have been proposed, which can selectively compensate the odd harmonics or 6k ± 1 harmonics with delay time reduced to T0/2 and T0/3, respectively. To further study in this area, this paper proposes an improved repetitive scheme implemented in a stationary...

  14. Development of a Novel, Oxidatively Activated, Safety-Catch Linker for Solid-Phase Asymmetric Organic Synthesis (SPOS)

    Institute of Scientific and Technical Information of China (English)

    LIN,Jun; Hjalmar Skarphedinsson; Stepehen G.Davies

    2004-01-01

    @@ Solid-phase asymmetric organic synthesis has become a very important synthetic strategy within the organic chemistry community.[1] Critical to success in SPOS is a linking strategy which allows both the substrate to be loaded and the product released efficiently from the polymeric support. A safety catch linker[2] (SCL) is in principle a linking molecule orthogonal to the reaction conditions of the library synthesis, which can be easily activated by a simple chemical transformation to allow efficient cleavage of the products from the polymer under mild conditions. In order to introduce the SuperQuat chiral auxiliaries[3] for SOPS, we report herein design and synthesis of a novel safety catch linker for asymmetric conjugate addition reactions.

  15. Minimizing the Levelized Cost of Energy in Single-Phase Photovoltaic Systems with an Absolute Active Power Control

    DEFF Research Database (Denmark)

    Yang, Yongheng; Koutroulis, Eftichios; Sangwongwanich, Ariya;

    2015-01-01

    Several countries with considerable PhotoVoltaic (PV) installations are facing a challenge of overloading the power infrastructure during peak-power production hours. Regulations have been imposed on the PV systems, where more active power control should be flexibly performed. As an advanced...... method is demonstrated on a 3-kW single-phase PV system considering a real-field mission profile (i.e., solar irradiance and ambient temperature). The optimization results have revealed that superior performance in terms of LCOE and energy production can be obtained by enabling the AAPC strategy......, compared to the conventional PV inverter operating only in the maximum power point tracking mode. In the presented case study, the minimum of LCOE is achieved for the system when the power limit is optimized to a certain level of the designed maximum feed-in power (i.e., 3 kW). In addition, the proposed...

  16. Minimizing the Levelized Cost of Energy in Single-Phase Photovoltaic Systems with an Absolute Active Power Control

    DEFF Research Database (Denmark)

    Yang, Yongheng; Koutroulis, Eftichios; Sangwongwanich, Ariya;

    2017-01-01

    Countries with considerable PhotoVoltaic (PV) installations are facing a challenge of overloading their power grid during peak-power production hours if the power infrastructure remains the same. To address this, regulations have been imposed on PV systems, where more active power control should...... Of Energy (LCOE), the power limit is optimized for the AAPC strategy in this paper. The optimization method is demonstrated on a 3-kW single-phase PV system considering a real-field mission profile (i.e., solar irradiance and ambient temperature). The optimization results have revealed that superior...... performance in terms of LCOE and energy production can be obtained by enabling the AAPC strategy, compared to the conventional PV inverter operating only in the maximum power point tracking mode. In the presented case study, the minimum of the LCOE is achieved for the PV system when the power limit...

  17. Determination of platelet-activating factor by reverse phase high-performance liquid chromatography and its application in viral hepatitis

    Institute of Scientific and Technical Information of China (English)

    Hong-Cui Cao; Xiao-Ming Chen; Wei Xu

    2005-01-01

    AIM: To detect the platelet-activating factor (PAF) and the plasma or serum levels of tumor necrosis factor-α (TNF-α) malondialdehyde (MDA), endotoxin (ET) and to discuss their significance in various types of viral hepatitis.METHODS: PAF, TNF-α, MDA, and ET levels in 60 controls, 16 cases of acute viral hepatitis, 71 cases of chronic viral hepatitis, 19 cases of severe viral hepatitis were detected by reverse phase high-performance liquid chromatography (rHPLC), bio-assay, ELISA, thiobarbituric acid (TBA), and limulus lysate test (LLT), respectively.RESULTS: The rHPLC was more sensitive and specific than bio-assay (r = 0.912, P<0.01). The plasma levels of PAF, TNF-α, MDA, and ET in patients with viral hepatitis were higher than those in controls (P<0.01).CONCLUSION: rHPLC is more reliable and accurate for the detection of PAF.

  18. Catalytic activity of bimetallic catalysts highly sensitive to the atomic composition and phase structure at the nanoscale

    Science.gov (United States)

    Shan, Shiyao; Petkov, Valeri; Prasai, Binay; Wu, Jinfang; Joseph, Pharrah; Skeete, Zakiya; Kim, Eunjoo; Mott, Derrick; Malis, Oana; Luo, Jin; Zhong, Chuan-Jian

    2015-11-01

    The ability to determine the atomic arrangement in nanoalloy catalysts and reveal the detailed structural features responsible for the catalytically active sites is essential for understanding the correlation between the atomic structure and catalytic properties, enabling the preparation of efficient nanoalloy catalysts by design. Herein we describe a study of CO oxidation over PdCu nanoalloy catalysts focusing on gaining insights into the correlation between the atomic structures and catalytic activity of nanoalloys. PdCu nanoalloys of different bimetallic compositions are synthesized as a model system and are activated by a controlled thermochemical treatment for assessing their catalytic activity. The results show that the catalytic synergy of Pd and Cu species evolves with both the bimetallic nanoalloy composition and temperature of the thermochemical treatment reaching a maximum at a Pd : Cu ratio close to 50 : 50. The nanoalloys are characterized structurally by ex situ and in situ synchrotron X-ray diffraction, including atomic pair distribution function analysis. The structural data show that, depending on the bimetallic composition and treatment temperature, PdCu nanoalloys adopt two different structure types. One features a chemically ordered, body centered cubic (B2) type alloy consisting of two interpenetrating simple cubic lattices, each occupied with Pd or Cu species alone, and the other structure type features a chemically disordered, face-centered cubic (fcc) type of alloy wherein Pd and Cu species are intermixed at random. The catalytic activity for CO oxidation is strongly influenced by the structural features. In particular, it is revealed that the prevalence of chemical disorder in nanoalloys with a Pd : Cu ratio close to 50 : 50 makes them superior catalysts for CO oxidation in comparison with the same nanoalloys of other bimetallic compositions. However, the catalytic synergy can be diminished if the Pd50Cu50 nanoalloys undergo phase

  19. Solid Phase Chemical Synthesis and Structure - Activity Study of Brevinin - 2R and Analogues as Antimicrobial Peptides

    Directory of Open Access Journals (Sweden)

    Hashem Yaghoubi

    2015-10-01

    Full Text Available Background: Brevinin-2R, as 25 amino acids peptide of the skin of Rana ridibunda frog, possesses potent antimicrobial and low hemolytic activity. It has an N-terminal hydrophilic region and a C-terminal loop that is delineated by an intra-disulfide bridge. In our study, Brevinin-2R and its diastereomer as well  as its  cyclic  analogue  were  synthesized  and  characterized  in  order  to investigate its structural features and biological implications.Methods: MIC determination is based on the recommended classical method of national comittee for labratory safety standard (NCLSS and standard by Hancock With some change on cationic peptides. In this study All bacterial strains were obtained from Industrial-Scientific Research center.Results: Both analogues showed lower antimicrobial activities compared to Brevinin-2R. In spite of Brevinin-2R peptide which shows low hemolytic activity, these analogues failed to show any hemolytic activity even at higherconcentrations (up to 400 µ g/ml. Based on proteolytic stability measurements,diastereomer and cyclic analogues displayed 90% and 60% residual antimicrobial activity, respectively, while antimicrobial activity of Brevinin-2R was 20%. The CD analysis revealed that amphipathic α-helical conformation of the synthesized peptides is involved in antimicrobial effects.Conclusion: CD studies and HPLC based measurement of retention time using a reverse phase column indicated that the Brevinin-2R can form an amphipathic loop  resulting  in  an  enhanced  hydrophobicity.  The  hemolytic  activity  ofBrevinin-2R and its analogues appeared to correlate with the retention time aswell as the α-helicity. Accordingly, it seems that the combination of incorporating of D-amino acids into lytic peptides and their cyclization may result in developing new antimicrobial peptides with improved properties for treating infectious diseases.

  20. Short-latency stretch reflexes do not contribute to premature calf muscle activity during the stance phase of gait in spastic patients

    NARCIS (Netherlands)

    Niet, M. de; Latour, H.; Hendricks, H.T.; Geurts, A.C.H.; Weerdesteijn, V.G.M.

    2011-01-01

    de Niet M, Latour H, Hendricks H, Geurts AC, Weerdesteyn V. Short-latency stretch reflexes do not contribute to premature calf muscle activity during the stance phase of gait in spastic patients. OBJECTIVE: To identify whether a relationship exists between stretch and activity of the calf muscles du

  1. Accurate and efficient calculation of excitation energies with the active-space particle-particle random phase approximation

    Science.gov (United States)

    Zhang, Du; Yang, Weitao

    2016-10-01

    An efficient method for calculating excitation energies based on the particle-particle random phase approximation (ppRPA) is presented. Neglecting the contributions from the high-lying virtual states and the low-lying core states leads to the significantly smaller active-space ppRPA matrix while keeping the error to within 0.05 eV from the corresponding full ppRPA excitation energies. The resulting computational cost is significantly reduced and becomes less than the construction of the non-local Fock exchange potential matrix in the self-consistent-field (SCF) procedure. With only a modest number of active orbitals, the original ppRPA singlet-triplet (ST) gaps as well as the low-lying single and double excitation energies can be accurately reproduced at much reduced computational costs, up to 100 times faster than the iterative Davidson diagonalization of the original full ppRPA matrix. For high-lying Rydberg excitations where the Davidson algorithm fails, the computational savings of active-space ppRPA with respect to the direct diagonalization is even more dramatic. The virtues of the underlying full ppRPA combined with the significantly lower computational cost of the active-space approach will significantly expand the applicability of the ppRPA method to calculate excitation energies at a cost of O(K4), with a prefactor much smaller than a single SCF Hartree-Fock (HF)/hybrid functional calculation, thus opening up new possibilities for the quantum mechanical study of excited state electronic structure of large systems.

  2. Benchmark of AC and DC active power decoupling circuits for second-order harmonic mitigation in kW-scale single-phase inverters

    DEFF Research Database (Denmark)

    Qin, Zian; Tang, Yi; Loh, Poh Chiang;

    2015-01-01

    This paper presents the benchmark study of ac and dc active power decoupling circuits for second-order harmonic mitigation in kW-scale single-phase inverters. First of all, the best solutions of active power decoupling to achieve high efficiency and power density are identified and comprehensively...... and reliability. The feasibility and superiority of the identified solution for active power decoupling together with the proposed adaptive decoupling voltage control method are finally verified by both the experimental results obtained on a 2 kW single-phase inverter....

  3. A novel, donor-active solvent-assisted liquid-phase microextraction procedure for spectrometric determination of zinc

    Energy Technology Data Exchange (ETDEWEB)

    Kocurova, Livia; Fatlova, Martina; Bazel, Yaroslav; Serbin, Rastislav; Andruch, Vasil, E-mail: liviamonika.kocurova@gmail.com [Department of Analytical Chemistry, University of P. J. Safarik, Kosice (Slovakia); Balogh, Ioseph S. [Department of Chemistry, College of Nyiregyhaza (Hungary); Simon, Andras [Department of General and Analytical Chemistry, Budapest University of Technology and Economics, Budapest (Hungary); Badida, Miroslav; Rusnak, Radoslav [Department of Environmentalistics, Faculty of Mechanical Engineering, Technical University of Kosice (Slovakia)

    2014-02-15

    Based on the reaction of Zn(II), thiocyanate and 2-[2-(5-dimethylamino-thiophen-2-yl)-vinyl]- 1,3,3-trimethyl-3H-indolium bromide (DTVTI), a donor-active solvent-assisted liquid-phase microextraction procedure followed by spectrophotometric determination of zinc at 570 nm was developed. The optimum experimental conditions were investigated and found to be as follows: concentration of NH{sub 4}SCN 0.02 mol L{sup -1} concentration of DTVTI 4 x 10{sup -5} mol L{sup -1}. Various extraction solvents were studied alone as well as in mixtures with different improvers, and a mixture of toluene as the extraction solvent and tributylphosphate as the donor-active solvent in a 4:1 v/v ratio was selected. The calibration plot was linear up to 2.62 mg L{sup 1} of zinc with limit of detection 0.09 mg L{sup -1}. The developed procedure was applied for zinc determination in dietary supplements. (author)

  4. A novel, donor-active solvent-assisted liquid-phase microextraction procedure for spectrometric determination of zinc

    International Nuclear Information System (INIS)

    Based on the reaction of Zn(II), thiocyanate and 2-[2-(5-dimethylamino-thiophen-2-yl)-vinyl]- 1,3,3-trimethyl-3H-indolium bromide (DTVTI), a donor-active solvent-assisted liquid-phase microextraction procedure followed by spectrophotometric determination of zinc at 570 nm was developed. The optimum experimental conditions were investigated and found to be as follows: concentration of NH4SCN 0.02 mol L-1 concentration of DTVTI 4 x 10-5 mol L-1. Various extraction solvents were studied alone as well as in mixtures with different improvers, and a mixture of toluene as the extraction solvent and tributylphosphate as the donor-active solvent in a 4:1 v/v ratio was selected. The calibration plot was linear up to 2.62 mg L1 of zinc with limit of detection 0.09 mg L-1. The developed procedure was applied for zinc determination in dietary supplements. (author)

  5. Gas-Phase Reactions of (n, γ) and Isomeric Transition-Activated Br80 with Alkanes and Haloalkanes

    International Nuclear Information System (INIS)

    Experimental data are presented on the gas-phase reactions of alkanes and haloalkanes with bromine atoms and ions activated by nuclear transformations. The target molecules include CH4 CD4, C2H6, C2D6, CH3Cl, CH2Cl2, CHCI3, CCl4, CH2F2, CHF3, CF4, C2F6, CF3Br, and CH3Br. The nuclear reactions and transformations used in producing the energetic recoil atoms and ions were Br80m (isomeric transition), Br80, and Br79 (n, γ) Br80. The percentage of the radioactivity found in organic combination (the organic yield, O. Y.) was determined as a function of the concentration of the target molecule in the mole-fraction range of about 0.95 to 1.00. Elemental Br2 served both as a source of hot atoms and as a scavenger. Usually 20-50 separate samples of each reaction system were examined and the data of O.Y. as a function of the concentration of scavenger were plotted and extrapolated to unit mole fraction of target molecule. In all cases, die O.Y. decreased with increasing halogen concentration. Data on the (n, γ) activated reactions of Br80 with isotopic alkanes suggest a comparable extrapolated O.Y. for C2H6 and C2D6, but an O.Y. for CD4 about half of the O.Y. with CH4. Gas chromatographic analysis of the organic products indicates that about 90% of the O.Y. in CH4 is caused by CH3Br and 10% by CH2Br2 For CD4 as the target the distribution of organic activity is approx. 75% CD3Br and 25% CD2Br2. These various data are discussed in terms of possible mechanisms involving hot halogen atoms and ions

  6. Piperine causes G1 phase cell cycle arrest and apoptosis in melanoma cells through checkpoint kinase-1 activation.

    Directory of Open Access Journals (Sweden)

    Neel M Fofaria

    Full Text Available In this study, we determined the cytotoxic effects of piperine, a major constituent of black and long pepper in melanoma cells. Piperine treatment inhibited the growth of SK MEL 28 and B16 F0 cells in a dose and time-dependent manner. The growth inhibitory effects of piperine were mediated by cell cycle arrest of both the cell lines in G1 phase. The G1 arrest by piperine correlated with the down-regulation of cyclin D1 and induction of p21. Furthermore, this growth arrest by piperine treatment was associated with DNA damage as indicated by phosphorylation of H2AX at Ser139, activation of ataxia telangiectasia and rad3-related protein (ATR and checkpoint kinase 1 (Chk1. Pretreatment with AZD 7762, a Chk1 inhibitor not only abrogated the activation of Chk1 but also piperine mediated G1 arrest. Similarly, transfection of cells with Chk1 siRNA completely protected the cells from G1 arrest induced by piperine. Piperine treatment caused down-regulation of E2F1 and phosphorylation of retinoblastoma protein (Rb. Apoptosis induced by piperine was associated with down-regulation of XIAP, Bid (full length and cleavage of Caspase-3 and PARP. Furthermore, our results showed that piperine treatment generated ROS in melanoma cells. Blocking ROS by tiron protected the cells from piperine mediated cell cycle arrest and apoptosis. These results suggest that piperine mediated ROS played a critical role in inducing DNA damage and activation of Chk1 leading to G1 cell cycle arrest and apoptosis.

  7. Selective pharmacological blockade of the 5-HT7 receptor attenuates light and 8-OH-DPAT induced phase shifts of mouse circadian wheel running activity

    Directory of Open Access Journals (Sweden)

    Jonathan eShelton

    2015-01-01

    Full Text Available Recent reports have illustrated a reciprocal relationship between circadian rhythm disruption and mood disorders. The 5-HT7 receptor may provide a crucial link between the two sides of this equation since the receptor plays a critical role in sleep, depression, and circadian rhythm regulation. To further define the role of the 5-HT7 receptor as a potential pharmacotherapy to correct circadian rhythm disruptions, the current study utilized the selective 5-HT7 antagonist JNJ-18038683 (10 mg/kg in three different circadian paradigms. While JNJ-18038683 was ineffective at phase shifting the onset of wheel running activity in mice when administered at different circadian time (CT points across the circadian cycle, pretreatment with JNJ-18038683 blocked non-photic phase advance (CT6 induced by the 5-HT1A/7 receptor agonist 8-OH-DPAT (3 mg/kg. Since light induced phase shifts in mammals are partially mediated via the modulation of the serotonergic system, we determined if JNJ-18038683 altered phase shifts induced by a light pulse at times known to phase delay (CT15 or advance (CT22 wheel running activity in free running mice. Light exposure resulted in a robust shift in the onset of activity in vehicle treated animals at both times tested. Administration of JNJ-18038683 significantly attenuated the light-induced phase delay and completely blocked the phase advance. The current study demonstrates that pharmacological blockade of the 5-HT7 receptor by JNJ-18038683 blunts both non-photic and photic phase shifts of circadian wheel running activity in mice. These findings highlight the importance of the 5-HT7 receptor in modulating circadian rhythms. Due to the opposite modulating effects of light resetting between diurnal and nocturnal species, pharmacotherapy targeting the 5-HT7 receptor in conjunction with bright light therapy may prove therapeutically beneficial by correcting the desynchronization of internal rhythms observed in depressed individuals.

  8. Zebrafish stem/progenitor factor msi2b exhibits two phases of activity mediated by different splice variants.

    Science.gov (United States)

    Hochgreb-Hägele, Tatiana; Koo, Daniel E S; Das, Neha M; Bronner, Marianne E

    2014-02-01

    The Musashi (Msi) family of RNA-binding proteins is important in stem and differentiating cells in many species. Here, we present a zebrafish gene/protein trap line gt(msi2b-citrine)(ct) (57) (a) that expresses a Citrine fusion protein with endogenous Msi2b. Our results reveal two phases of Msi2b expression: ubiquitous expression in progenitor cells in the early embryo and later, tissue-specific expression in differentiating cells in the olfactory organ, pineal gland, and subpopulations of neurons in the central nervous system (CNS). Interestingly, this division between early and late phases is paralleled by differential expression of msi2b alternative splicing products. Whereas the full-length and long variant v3 Msi2b predominate at early stages, the later expression of variants in differentiating tissues appears to be tissue specific. Using the gt(msi2b-citrine)(ct) (57) (a), we characterized tissue-specific expression of Msi2b with cellular resolution in subsets of differentiating cells in the olfactory organ, pineal gland, CNS, and ventral neural tube. By performing transcription activator-like effectors nuclease-mediated biallelic genome editing or morpholino knockdown of Msi2b in zebrafish, our results show that early inactivation of Msi2b results in severe embryonic defects including hypertrophy of the ventricles and shortening of the body, consistent with an important role in cell proliferation and survival. Moreover, specific inactivation of Msi2b full-length indicates that this species is essential for the early role of Msi2b. This line provides a valuable tool both for live imaging of the endogenous Msi2b at subcellular resolution and manipulation of Msi2b-expressing cells.

  9. Disposal of chemical agents and munitions stored at Umatilla Depot Activity, Hermiston, Oregon. Final Phase 1 environmental report

    Energy Technology Data Exchange (ETDEWEB)

    Zimmerman, G.P.; Hillsman, E.L.; Johnson, R.O.; Miller, R.L.; Patton, T.G.; Schoepfle, G.M.; Tolbert, V.R.; Feldman, D.L.; Hunsaker, D.B. Jr.; Kroodsma, R.L.; Morrissey, J.; Rickert, L.W.; Staub, W.P.; West, D.C.

    1993-02-01

    The Umatilla Depot Activity (UMDA) near Hermiston, Oregon, is one of eight US Army installations in the continental United States where lethal unitary chemical agents and munitions are stored, and where destruction of agents and munitions is proposed under the Chemical Stockpile Disposal Program (CSDP). The chemical agent inventory at UMDA consists of 11.6%, by weight, of the total US stockpile. The destruction of the stockpile is necessary to eliminate the risk to the public from continued storage and to dispose of obsolete and leaking munitions. In 1988 the US Army issued a Final Programmatic Environmental Impact Statement (FPEIS) for the CSDP that identified on-site disposal of agents and munitions as the environmentally preferred alternative (i.e., the alternative with the least potential to cause significant adverse impacts), using a method based on five measures of risk for potential human health and ecosystem/environmental effects; the effectiveness and adequacy of emergency preparedness capabilities also played a key role in the FPEIS selection methodology. In some instances, the FPEIS included generic data and assumptions that were developed to allow a consistent comparison of potential impacts among programmatic alternatives and did not include detailed conditions at each of the eight installations. The purpose of this Phase 1 report is to examine the proposed implementation of on-site disposal at UMDA in light of more recent and more detailed data than those included in the FPEIS. Specifically, this Phase 1 report is intended to either confirm or reject the validity of on-site disposal for the UMDA stockpile. Using the same computation methods as in the FPEIS, new population data were used to compute potential fatalities from hypothetical disposal accidents. Results indicate that onsite disposal is clearly preferable to either continued storage at UMDA or transportation of the UMDA stockpile to another depot for disposal.

  10. Direct observation of solid-phase adsorbate concentration profile in powdered activated carbon particle to elucidate mechanism of high adsorption capacity on super-powdered activated carbon.

    Science.gov (United States)

    Ando, Naoya; Matsui, Yoshihiko; Matsushita, Taku; Ohno, Koichi

    2011-01-01

    Decreasing the particle size of powdered activated carbon (PAC) by pulverization increases its adsorption capacities for natural organic matter (NOM) and polystyrene sulfonate (PSS, which is used as a model adsorbate). A shell adsorption mechanism in which NOM and PSS molecules do not completely penetrate the adsorbent particle and instead preferentially adsorb near the outer surface of the particle has been proposed as an explanation for this adsorption capacity increase. In this report, we present direct evidence to support the shell adsorption mechanism. PAC particles containing adsorbed PSS were sectioned with a focused ion beam, and the solid-phase PSS concentration profiles of the particle cross-sections were directly observed by means of field emission-scanning electron microscopy/energy-dispersive X-ray spectrometry (FE-SEM/EDXS). X-ray emission from sulfur, an index of PSS concentration, was higher in the shell region than in the inner region of the particles. The X-ray emission profile observed by EDXS did not agree completely with the solid-phase PSS concentration profile predicted by shell adsorption model analysis of the PSS isotherm data, but the observed and predicted profiles were not inconsistent when the analytical errors were considered. These EDXS results provide the first direct evidence that PSS is adsorbed mainly in the vicinity of the external surface of the PAC particles, and thus the results support the proposition that the increase in NOM and PSS adsorption capacity with decreasing particle size is due to the increase in external surface area on which the molecules can be adsorbed. PMID:20851447

  11. The simultaneous determination of active ingredients in cough-cold mixtures by isocratic reversed-phase ion-pair high-performance liquid chromatography.

    Science.gov (United States)

    Lau, O W; Chan, K; Lau, Y K; Wong, W C

    1989-01-01

    A simple, rapid and accurate method for the simultaneous determination of active ingredients in cough-cold mixtures using isocratic reversed-phase ion-pair high-performance liquid chromatography has been developed. It involves the use of an octadecylsilane column as the stationary phase with methanol, water, tetrahydrofuran, phosphoric acid mixtures as mobile phase including sodium dioctylsulphosuccinate as the ion-pair agent. The pH of the mobile phase was adjusted to 4.6 by means of phosphoric acid and ammonium hydroxide solutions. The proposed method involves the simple dilution of the samples with the mobile phase and the addition of metoclopramide hydrochloride as the internal standard. The active ingredients under investigation were chlorpheniramine, codeine, diphenhydramine, ephedrine, ethylmorphine, phenylephrine, phenylpropanolamine and pholcodine, which exist as various combinations in cough-cold mixtures. The optimum composition of the mobile phase and the optimum flow rate were determined and are reported. The method was applied to the determination of active ingredients in seven commercially available cough-cold mixtures.

  12. The simultaneous determination of active ingredients in cough-cold mixtures by isocratic reversed-phase ion-pair high-performance liquid chromatography.

    Science.gov (United States)

    Lau, O W; Chan, K; Lau, Y K; Wong, W C

    1989-01-01

    A simple, rapid and accurate method for the simultaneous determination of active ingredients in cough-cold mixtures using isocratic reversed-phase ion-pair high-performance liquid chromatography has been developed. It involves the use of an octadecylsilane column as the stationary phase with methanol, water, tetrahydrofuran, phosphoric acid mixtures as mobile phase including sodium dioctylsulphosuccinate as the ion-pair agent. The pH of the mobile phase was adjusted to 4.6 by means of phosphoric acid and ammonium hydroxide solutions. The proposed method involves the simple dilution of the samples with the mobile phase and the addition of metoclopramide hydrochloride as the internal standard. The active ingredients under investigation were chlorpheniramine, codeine, diphenhydramine, ephedrine, ethylmorphine, phenylephrine, phenylpropanolamine and pholcodine, which exist as various combinations in cough-cold mixtures. The optimum composition of the mobile phase and the optimum flow rate were determined and are reported. The method was applied to the determination of active ingredients in seven commercially available cough-cold mixtures. PMID:2577452

  13. Reduction of liver function delays resumption of postpartum ovarian activity and alters the synthesis of acute phase proteins in dairy cows.

    Science.gov (United States)

    Montagner, Paula; Krause, Ana Rita Tavares; Schwegler, Elizabeth; Weschenfelder, Marina Menoncin; Rabassa, Viviane Rohrig; Schneider, Augusto; Pereira, Rubens Alves; Brauner, Cássio Cassal; Del Pino, Francisco Augusto Burkert; Gonçalves, Fernanda Medeiros; Corrêa, Marcio Nunes

    2016-06-01

    The aim of this study was to evaluate the concentration of acute phase proteins, milk production, and resumption of postpartum ovarian activity of clinically healthy dairy cows in a semi-extensive system with different Liver Functionality Index (LFI) values. The animals were divided into two groups: Low LFI (LLFI: -7 to -12; n: 10) and High LFI (HLFI: -7 to -4; n: 10). Animals with LLFI had lower paraoxonase activity and lower albumin concentration in the pre- and postpartum periods (Pacute phase proteins and the first ovulation interval, and it can be used to improve the production and reproductive performance. PMID:27234541

  14. Relation between phase composition and photocatalytic activity of TiO{sub 2} in a sulfoxide deoxygenation reaction

    Energy Technology Data Exchange (ETDEWEB)

    Molinari, Alessandra, E-mail: alessandra.molinari@unife.it [Dipartimento di Scienze Chimiche e Farmaceutiche, Università di Ferrara, Via Fossato di Mortara 17, 44121 Ferrara (Italy); Bonino, Francesca; Magnacca, Giuliana [Dipartimento di Chimica, NIS and INSTM Reference Centre, Università di Torino, Via G. Quarello 15, I-10135 and Via P. Giuria 7, I-10125, Turin (Italy); Demaria, Francesca; Maldotti, Andrea [Dipartimento di Scienze Chimiche e Farmaceutiche, Università di Ferrara, Via Fossato di Mortara 17, 44121 Ferrara (Italy)

    2015-05-05

    In the present study we synthesize three TiO{sub 2} samples, TiO{sub 2}-500, TiO{sub 2}-750 and TiO{sub 2}-850, by a sol–gel procedure varying the rutile and anatase content by calcination at different temperatures. Characterization by XRD, NIR-Raman, UV-Raman, BET, DR-UV-Vis spectroscopy and SEM points out that TiO{sub 2}-500 consists mainly of anatase and TiO{sub 2}-850 of rutile. TiO{sub 2}-700 presents both phases on the surface that is the part of the photocatalyst interested by UV illumination. The photocatalysts are tested in the deoxygenation reaction of methyl p-tolyl sulfoxide to the corresponding sulfide using 2-propanol as hole scavenger. It is demonstrated that the presence of both anatase and rutile on the surface of TiO{sub 2}-700 is responsible of the increase of the photocatalytic activity. This is likely due to a more efficient charge separation process that increases lifetime of the charges giving availability of electrons and holes for the photocatalytic reaction. Methyl p-tolyl sulfide is formed with a selectivity of 100%. - Highlights: • TiO{sub 2} samples are synthesized via sol–gel varying the rutile and anatase composition. • TiO{sub 2}-700 (calcined at 700 °C) presents both anatase and rutile on the surface. • Efficient charges separation is allowed by the presence of anatase and rutile. • Spatial separation of charges renders TiO{sub 2}-700 the most active photocatalyst. • Methyl p-tolyl sulfoxide is transformed in sulfide with 100% selectivity.

  15. A comparative study of the CFD modeling of a ventilated active façade including phase change materials

    International Nuclear Information System (INIS)

    Highlights: • A CFD model of a ventilated active façade with PCM was developed. • Results were validated against real-scale experimental data. • Convection effects within PCM can be neglected in for the façade under study. • DO radiation model and RNG k–ε showed accurate results for air turbulent flow regime. • k–ω models showed better accuracy than the RNG k–ε model for transitional air flows. - Abstract: This article describes the development of a CFD 2D model of a new type of ventilated active façade which includes a PCM (Phase Change Material) in its outer layer. The model was carried out using the software Fluent. The numerical results were compared against experimental data obtained by means of a real-scale PASLINK test facility. Two different approaches were tested to model the PCM. To model the radiation, S2S and DO sub-models were tested. RNG k–ε, Standard k–ω and SST k–ω turbulence models were compared to model the air flow inside the ventilated layer. The results showed that for the geometry under consideration it was suitable to consider the PCM to be a solid material with variable Cp. The DO model accurately reproduced the radiation phenomena. For an air flow rate that resulted in a turbulent regime inside the air chamber, the RNG k–ε model showed good agreement between the experimental data and the simulated results. The developed model can be considered suitable for the simulation and optimization of the fa ade under turbulent flow conditions. Further research should be conducted to improve the accuracy of the model for low-Reynolds-number turbulence conditions

  16. Distending Pressure Did Not Activate Acute Phase or Inflammatory Responses in the Airways and Lungs of Fetal, Preterm Lambs.

    Directory of Open Access Journals (Sweden)

    Rebecca Y Petersen

    Full Text Available Mechanical ventilation at birth causes airway injury and lung inflammation in preterm sheep. Continuous positive airway pressure (CPAP is being increasingly used clinically to transition preterm infants at birth.To test if distending pressures will activate acute phase reactants and inflammatory changes in the airways of fetal, preterm lambs.The head and chest of fetal lambs at 128±1 day GA were surgically exteriorized. With placental circulation intact, fetal lambs were then randomized to one of five 15 minute interventions: PEEP of 0, 4, 8, 12, or 16 cmH2O. Recruitment volumes were recorded. Fetal lambs remained on placental support for 30 min after the intervention. The twins of each 0 cmH2O animal served as controls. Fetal lung fluid (FLF, bronchoalveolar lavage fluid (BAL, right mainstem bronchi and peripheral lung tissue were evaluated for inflammation.Recruitment volume increased from 0.4±0.04 mL/kg at 4 cmH2O to 2.4±0.3 mL/kg at 16 cmH2O. The lambs were surfactant deficient, and all pressures were below the opening inflection pressure on pressure-volume curve. mRNA expression of early response genes and pro-inflammatory cytokines did not increase in airway tissue or lung tissue at any pressure compared to controls. FLF and BAL also did not have increases in early response proteins. No histologic changes or Egr-1 activation was present at the pressures used.Distending pressures as high as 16 cmH2O did not recruit lung volume at birth and did not increase markers of injury in the lung or airways in non-breathing preterm fetal sheep.

  17. Time-resolved phase-change recording mark formation with zinc oxide near-field optical active layer

    Science.gov (United States)

    Kao, Tsung Sheng; Chen, Mu-Ku; Chen, Jia-Wern; Chen, Yi-Hao; Wu, Pei Ru; Tsai, Din Ping

    2015-09-01

    In this paper, an optical active thin film of zinc oxide (ZnOx) nano-composites exploited for the enhancement of optical signals in an ultra-high density recording scheme has been demonstrated. Via the electron microscope investigation, the results display randomly distributed crystalline nanograins in the ZnOx thin films. Optical disks with the ZnOx nanostructured thin films show that the carrier-to-noise ratio (CNR) above 25 dB can be obtained at the mark trains of 100 nm, while the optimal writing power is reduced as a function of the increasing thickness of the ZnOx films. Furthermore, by conducting a series of the optical pump-probe experiments, the optical responses of recording marks on as-deposited phase-change Ge2Sb2Te5 (as-GST) recording layers present that the highly contrast bright recording bits can be acquired with the existence of the ZnOx nanostructured thin films, providing prospective potentials in future data storage and optoelectronic devices.

  18. Effect of Dance Labor on the Management of Active Phase Labor Pain & Clients’ Satisfaction: A Randomized Controlled Trial Study

    Science.gov (United States)

    Abdolahian, Somayeh; Ghavi, Fatemeh; Abdollahifard, Sareh; Sheikhan, Fatemeh

    2014-01-01

    Background: There are a wide variety of non- pharmacologic pain relief techniques for labor which include pelvic movement, upright position, back massage and partner support during the first stage of labor. The effectiveness of dance labor- which is a combination of these techniques- has not been evaluated. Aim: This study aimed to evaluate the effectiveness of dance labor in pain reduction and woman’s satisfaction during the first stage of labor. Methods: 60 primiparous women aged 18-35 years old were randomly assigned to dance labor and control groups. In the dance labor group, women were instructed to do standing upright with pelvic tilt and rock their hips back and forth or around in a circle while their partner massaged their back and sacrum for a minimum of 30 minutes. In the control group, the participants received usual care during physiologic labor. Pain and satisfaction scores were measured by Visual Analogue Scale. Data were analyzed by using the t. test and Chi-square. Findings: Mean pain score in the dance labor group was significantly lower than the control group (P < 0.05). The mean satisfaction score in the dance labor group was significantly higher than in the control group (P < 0.05). Conclusion: Dance labor which is a complementary treatment with low risk can reduce the intensity of pain and increase mothers, satisfaction with care during the active phase of labor. PMID:24762366

  19. Increased temperature in the thermophilic stage in temperature phased anaerobic digestion (TPAD) improves degradability of waste activated sludge.

    Science.gov (United States)

    Ge, Huoqing; Jensen, Paul D; Batstone, Damien J

    2011-03-15

    Two-stage temperature phased anaerobic digestion (TPAD) is an increasingly popular method to improve stabilisation of sewage waste activated sludge, which normally has inherently poor and slow degradation. However, there has been limited systematic analysis of the impact of the initial thermophilic stage (temperature, pH and retention time) on performance in the main mesophilic stage. In this study, we demonstrate a novel two-stage batch test method for TPAD processes, and use it to optimize operating conditions of the thermophilic stage in terms of degradation extent and methane production. The method determines overall degradability and apparent hydrolysis coefficient in both stages. The overall process was more effective with short pre-treatment retention times (1-2 days) and neutral pH compared to longer retention time (4 days) and low pH (4-5). Degradabilities and apparent hydrolysis coefficients were 0.3-0.5 (fraction degradable) and 0.1-0.4d(-1), respectively, with a margin of error in each measurement of approximately 20% relative (95% confidence). Pre-treatment temperature had a strong impact on the whole process, increasing overall degradability from 0.3 to 0.5 as temperature increased from 50 to 65 °C, with apparent hydrolysis coefficient increasing from 0.1 to 0.4d(-1). PMID:21277081

  20. The upper Pleistocene on the northern face of the Guadarrama Mountains (central Spain): Palaeoclimatic phases and glacial activity

    Science.gov (United States)

    Bullón, Teresa

    2016-09-01

    The present paper provides new information on Pleistocene glacial activity in a mountainous area of the Iberian Central System. A sediment analysis associated with Pleistocene modelling was carried out using: (1) granulometric and morphometric procedures, (2) quartz grain microtexture techniques (SEM) to discriminate between glacial and no glacial origins of sediments, (3) clay X-ray diffraction study to determine intra-Pleistocene climate variability, and (4) optically stimulated luminescence (OSL) absolute dating. The results show that the sediments were formed in two different phases associated with glacial dynamics, one of them was 35-30 ky BP and another was 25-20 ky BP, separated by a short intermediate warm-wet period. Identification of glacial phenomena is new for the northern slopes of the Guadarrama Mountains (facing the north Meseta, Duero basin), although they are not unusual within the general context of the Iberian Central System. From the data provided, we deduce that glaciation in these mountains was much more intense and widespread than had previously been thought because, on the northern slopes, glaciers occupied large areas reaching the base of the mountains. The evidence favours new interpretations of Pleistocene morphology in the centre of the Iberian Peninsula and, by extension, on the southwestern edge of Europe; it also highlights the sensitivity of mountainous areas with regard to Quaternary climate changes.

  1. Tissue-type plasminogen activator-plasmin-BDNF modulate glutamate-induced phase-shifts of the mouse suprachiasmatic circadian clock in vitro.

    Science.gov (United States)

    Mou, Xiang; Peterson, Cynthia B; Prosser, Rebecca A

    2009-10-01

    The mammalian circadian clock in the suprachiasmatic nucleus (SCN) maintains environmental synchrony through light signals transmitted by glutamate released from retinal ganglion terminals. Brain-derived neurotrophic factor (BDNF) is required for light/glutamate to reset the clock. In the hippocampus, BDNF is activated by the extracellular protease, plasmin, which is produced from plasminogen by tissue-type plasminogen activator (tPA). We provide data showing expression of proteins from the plasminogen activation cascade in the SCN and their involvement in circadian clock phase-resetting. Early night glutamate application to SCN-containing brain slices resets the circadian clock. Plasminogen activator inhibitor-1 (PAI-1) blocked these shifts in slices from wild-type mice but not mice lacking its stabilizing protein, vitronectin (VN). Plasmin, but not plasminogen, prevented inhibition by PAI-1. Both plasmin and active BDNF reversed alpha(2)-antiplasmin inhibition of glutamate-induced shifts. alpha(2)-Antiplasmin decreased the conversion of inactive to active BDNF in the SCN. Finally, both tPA and BDNF allowed daytime glutamate-induced phase-resetting. Together, these data are the first to demonstrate expression of these proteases in the SCN, their involvement in modulating photic phase-shifts, and their activation of BDNF in the SCN, a potential 'gating' mechanism for photic phase-resetting. These data also demonstrate a functional interaction between PAI-1 and VN in adult brain. Given the usual association of these proteins with the extracellular matrix, these data suggest new lines of investigation into the locations and processes modulating mammalian circadian clock phase-resetting.

  2. Plasmid DNA Supercoiling and Gyrase Activity in Escherichia coli Wild-Type and rpoS Stationary-Phase Cells

    Science.gov (United States)

    Reyes-Domínguez, Yazmid; Contreras-Ferrat, Gabriel; Ramírez-Santos, Jesús; Membrillo-Hernández, Jorge; Gómez-Eichelmann, M. Carmen

    2003-01-01

    Stationary-phase cells displayed a distribution of relaxed plasmids and had the ability to recover plasmid supercoiling as soon as nutrients became available. Preexisting gyrase molecules in these cells were responsible for this recovery. Stationary-phase rpoS cells showed a bimodal distribution of plasmids and failed to supercoil plasmids after the addition of nutrients, suggesting that rpoS plays a role in the regulation of plasmid topology during the stationary phase. PMID:12533486

  3. Application of Backstepping to the Virtual Flux Direct Power Control of Five-Level Three-Phase Shunt Active Power Filter

    Directory of Open Access Journals (Sweden)

    Bouzidi Mansour

    2014-03-01

    Full Text Available This paper proposes a virtual flux direct power control-space vector modulation combined with backstepping control for three-phase five-level neutral point clamped shunt active power filter. The main goal of the proposed active filtering system is to eliminate the unwanted harmonics and compensate fundamental reactive power drawn from the nonlinear loads. In this study, the voltage-balancing control of four split dc capacitors of the five-level active filter is achieved using five-level space vector modulation with balancing strategy based on the effective use of the redundant switching states of the inverter voltage vectors. The obtained results showed that, the proposed multilevel shunt active power filter with backstepping control can produce a sinusoidal supply current with low harmonic distortion and in phase with the line voltage.

  4. Stable phase-shift despite quasi-rhythmic movements: a CPG-driven dynamic model of active tactile exploration in an insect

    Directory of Open Access Journals (Sweden)

    Nalin eHarischandra

    2015-08-01

    Full Text Available An essential component of autonomous and flexible behaviour in animals is active exploration of the environment, allowing for perception-guided planning and control of actions. An important sensory system involved is active touch. Here, we introduce a general modelling framework of Central Pattern Generators (CPGs for movement generation in active tactile exploration behaviour. The CPG consists of two network levels: (i phase-coupled Hopf oscillators for rhythm generation, and (ii pattern formation networks for capturing the frequency and phase characteristics of individual joint oscillations. The model captured the natural, quasi-rhythmic joint kinematics as observed in coordinated antennal movements of walking stick insects. Moreover, it successfully produced tactile exploration behaviour on a three-dimensional skeletal model of the insect antennal system with physically realistic parameters. The effect of proprioceptor ablations could be simulated by changing the amplitude and offset parameters of the joint oscillators, only. As in the animal, the movement of both antennal joints was coupled with a stable phase difference, despite the quasi-rhythmicity of the joint angle time courses. We found that the phase-lead of the distal scape-pedicel joint relative to the proximal head-scape joint was essential for producing the natural tactile exploration behaviour and, thus, for tactile efficiency. For realistic movement patterns, the phase-lead could vary within a limited range of 10 to 30 degrees only. Tests with artificial movement patterns strongly suggest that this phase sensitivity is not a matter of the frequency composition of the natural movement pattern. Based on our modelling results, we propose that a constant phase difference is coded into the CPG of the antennal motor system and that proprioceptors are acting locally to regulate the joint movement amplitude.

  5. Liquid and vapour-phase antifungal activities of selected essential oils against candida albicans: microscopic observations and chemical characterization of cymbopogon citratus

    Directory of Open Access Journals (Sweden)

    Malik Anushree

    2010-11-01

    Full Text Available Abstract Background Use of essential oils for controlling Candida albicans growth has gained significance due to the resistance acquired by pathogens towards a number of widely-used drugs. The aim of this study was to test the antifungal activity of selected essential oils against Candida albicans in liquid and vapour phase and to determine the chemical composition and mechanism of action of most potent essential oil. Methods Minimum Inhibitory concentration (MIC of different essential oils in liquid phase, assayed through agar plate dilution, broth dilution & 96-well micro plate dilution method and vapour phase activity evaluated through disc volatilization method. Reduction of C. albicans cells with vapour exposure was estimated by kill time assay. Morphological alteration in treated/untreated C. albicans cells was observed by the Scanning electron microscopy (SEM/Atomic force microscopy (AFM and chemical analysis of the strongest antifungal agent/essential oil has been done by GC, GC-MS. Results Lemon grass (Cymbopogon citratus essential oil exhibited the strongest antifungal effect followed by mentha (Mentha piperita and eucalyptus (Eucalyptus globulus essential oil. The MIC of lemon grass essential oil in liquid phase (288 mg/l was significantly higher than that in the vapour phase (32.7 mg/l and a 4 h exposure was sufficient to cause 100% loss in viability of C. albicans cells. SEM/AFM of C. albicans cells treated with lemon grass essential oil at MIC level in liquid and vapour phase showed prominent shrinkage and partial degradation, respectively, confirming higher efficacy of vapour phase. GC-MS analysis revealed that lemon grass essential oil was dominated by oxygenated monoterpenes (78.2%; α-citral or geranial (36.2% and β-citral or neral (26.5%, monoterpene hydrocarbons (7.9% and sesquiterpene hydrocarbons (3.8%. Conclusion Lemon grass essential oil is highly effective in vapour phase against C. albicans, leading to deleterious

  6. A phase II, multicenter, open-label study evaluating dosing and preliminary safety and efficacy of canakinumab in systemic juvenile idiopathic arthritis with active systemic features

    NARCIS (Netherlands)

    Ruperto, Nicolino; Quartier, Pierre; Wulffraat, Nico; Woo, Patricia; Ravelli, Angelo; Mouy, Richard; Bader-Meunier, Brigitte; Vastert, Sebastiaan J.; Noseda, Emanuele; D'Ambrosio, Daniele; Lecot, Jean; Chakraborty, Abhijit; Martini, Alberto; Chioato, Andrea

    2012-01-01

    Objective To assess dosing, preliminary safety, and efficacy of canakinumab, a fully human antiinterleukin-1 beta (antiIL-1 beta) antibody, in children with systemic juvenile idiopathic arthritis (JIA) and active systemic features. Methods. In this phase II, multicenter, openlabel, dosage-escalation

  7. Solid-phase organic synthesis of 2-tridecanyl-1,4-naphthoquinone and 2-tridecanyl-1,4-naphthodiol that form redox-active micelles and vesicles.

    Science.gov (United States)

    Bugarin, Alejandro; Martinez, Luis E; Cooke, Peter; Islam, Tadiqul; Noveron, Juan C

    2014-10-01

    The solid-phase synthesis of new amphiphilic compounds is reported. It is based on a newly designed 1,4-naphthoquinone derivative that contains polar and nonpolar groups and self-assembles into micelles or vesicles in water depending on the concentration. They also display redox-active properties.

  8. Report of the Phase 1 of the Validation of the Fish Sexual Development Test for the Detection of Endocrine Active Substances

    DEFF Research Database (Denmark)

    Holbech, Henrik; Kinnberg, Karin Lund; Petersen, Gitte

    This document presents the validation report (phase 1) of the Fish Sexual Development Test (FSDT). The FSDT covers a life-stage where sexual development is particularly sensitive to perturbation caused by endocrine active chemicals. The chemical exposure lasts for about 60 days, at the end of which...

  9. Transcriptional regulation of the redD transcriptional activator gene accounts for growth-phase-dependent production of the antibiotic undecylprodigiosin in Streptomyces coelicolor A3(2)

    NARCIS (Netherlands)

    Takano, E.; Gramajo, H.C.; Strauch, E.; White, J.; Bibb, M.J.

    1992-01-01

    Transcription of redD, the activator gene required for production of the red-pigmented antibiotic undecylprodigiosin by Streptomyces coelicolor A3(2), showed a dramatic increase during the transition from exponential to stationary phase. The increase in redD expression was followed by transcription

  10. Different Phases of Long-Term Memory Require Distinct Temporal Patterns of PKA Activity after Single-Trial Classical Conditioning

    Science.gov (United States)

    Michel, Maximilian; Kemenes, Ildiko; Muller, Uli; Kemenes, Gyorgy

    2008-01-01

    The cAMP-dependent protein kinase (PKA) is known to play a critical role in both transcription-independent short-term or intermediate-term memory and transcription-dependent long-term memory (LTM). Although distinct phases of LTM already have been demonstrated in some systems, it is not known whether these phases require distinct temporal patterns…

  11. LOW ACTIVATION JOINING OF SIC/SIC COMPOSITES FOR FUSION APPLICATIONS: MODELING DUAL-PHASE MICROSTRUCTURES AND DISSIMILAR MATERIAL JOINTS

    Energy Technology Data Exchange (ETDEWEB)

    Henager, Charles H.; Nguyen, Ba Nghiep; Kurtz, Richard J.; Ferraris, M.; Katoh, Y.

    2016-03-31

    Finite element continuum damage models (FE-CDM) have been developed to simulate and model dual-phase joints and cracked joints for improved analysis of SiC materials in nuclear environments. This report extends the analysis from the last reporting cycle by including results from dual-phase models and from cracked joint models.

  12. Enhanced visible-light photocatalytic activity for selective oxidation of amines into imines over TiO{sub 2}(B)/anatase mixed-phase nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Jun [Institute of Applied Chemistry, Henan Polytechnic University, Jiaozuo 454003 (China); State Key Laboratory Cultivation Base for Gas Geology and Gas Control, School of Safety Science and Engineering, Henan Polytechnic University, Jiaozuo 454003 (China); Yang, Juan, E-mail: yangjuanhpu@yahoo.com [Institute of Applied Chemistry, Henan Polytechnic University, Jiaozuo 454003 (China); Wang, Xiaohan; Zhang, Lei; Li, Yingjie [Institute of Applied Chemistry, Henan Polytechnic University, Jiaozuo 454003 (China)

    2015-09-15

    Graphical abstract: Visible-light photocatalytic activities for selective oxidation of amines into imines are greatly affected by the crystal structure of TiO{sub 2} catalysts and mixed-phase TiO{sub 2}(B)/anatase possess higher photoactivity because of the moderate adsorption ability and efficient charge separation. - Highlights: • Visible-light photocatalytic oxidation of amines to imines is studied over different TiO{sub 2}. • Photocatalytic activities are greatly affected by the crystal structure of TiO{sub 2} nanowires. • Mixed-phase TiO{sub 2}(B)/anatase exhibits higher catalytic activity than single-phase TiO{sub 2}. • Enhanced activity is ascribed to efficient adsorption ability and interfacial charge separation. • Photoinduced charge transfer mechanism on TiO{sub 2}(B)/anatase catalysts is also proposed. - Abstract: Wirelike catalysts of mixed-phase TiO{sub 2}(B)/anatase TiO{sub 2}, bare anatase TiO{sub 2} and TiO{sub 2}(B) are synthesized via calcining precursor hydrogen titanate obtained from hydrothermal process at different temperatures between 450 and 700 °C. Under visible light irradiation, mixed-phase TiO{sub 2}(B)/anatase TiO{sub 2} catalysts exhibit enhanced photocatalytic activity in comparison with pure TiO{sub 2}(B) and anatase TiO{sub 2} toward selective oxidation of benzylamines into imines and the highest photocatalytic activity is achieved by TW-550 sample consisting of 65% TiO{sub 2}(B) and 35% anatase. The difference in photocatalytic activities of TiO{sub 2} samples can be attributed to the different adsorption abilities resulted from their crystal structures and interfacial charge separation driven by surface-phase junctions between TiO{sub 2}(B) and anatase TiO{sub 2}. Moreover, the photoinduced charge transfer mechanism of surface complex is also proposed over mixed-phase TiO{sub 2}(B)/anatase TiO{sub 2} catalysts. Advantages of this photocatalytic system include efficient utilization of solar light, general suitability to

  13. Controllable drug uptake and nongenomic response through estrogen-anchored cyclodextrin drug complex

    Directory of Open Access Journals (Sweden)

    Yin JJ

    2015-07-01

    Full Text Available Juan-Juan Yin,1,2 Stepan P Shumyak,2 Christopher Burgess,2 Zhi-Wei Zhou,2 Zhi-Xu He,3 Xue-Ji Zhang,4 Shu-Ting Pan,2,5 Tian-Xin Yang,6 Wei Duan,7 Jia-Xuan Qiu,5 Shu-Feng Zhou21Xiaolan People’s Hospital, Southern Medical University, Zhongshan, Guangdong, People’s Republic of China; 2Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, FL, USA; 3Guizhou Provincial Key Laboratory for Regenerative Medicine, Stem Cell and Tissue Engineering Research Center and Sino-US Joint Laboratory for Medical Sciences, Guizhou Medical University, Guiyang, Guizhou, 4Research Center for Bioengineering and Sensing Technology, University of Science and Technology Beijing, Beijing, 5Department of Oral and Maxillofacial Surgery, the First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People’s Republic of China; 6Department of Internal Medicine, University of Utah and Salt Lake Veterans Affairs Medical Center, Salt Lake City, UT, USA; 7School of Medicine, Deakin University, Waurn Ponds, VIC, AustraliaAbstract: Breast cancer is a leading killer of women worldwide. Cyclodextrin-based estrogen receptor-targeting drug-delivery systems represent a promising direction in cancer therapy but have rarely been investigated. To seek new targeting therapies for membrane estrogen receptor-positive breast cancer, an estrogen-anchored cyclodextrin encapsulating a doxorubicin derivative Ada-DOX (CDE1-Ada-DOX has been synthesized and evaluated in human breast cancer MCF-7 cells. First, we synthesized estrone-conjugated cyclodextrin (CDE1, which formed the complex CDE1-Ada-DOX via molecular recognition with the derivative adamantane-doxorubicin (Ada-DOX (Kd=1,617 M-1. The structure of the targeting vector CDE1 was fully characterized using 1H- and 13C-nuclear magnetic resonance, mass spectrometry, and electron microscopy. CDE1-Ada-DOX showed two-phase drug-release kinetics with much slower release than Ada-DOX. The

  14. Effect of Gold Dispersion on the Photocatalytic Activity of Mesoporous Titania for the Vapor-Phase Oxidation of Acetone

    Directory of Open Access Journals (Sweden)

    S. V. Awate

    2008-01-01

    Full Text Available Mesostructured titanium dioxide photocatalyst, having uniform crystallite size (6–12 nm and average pore diameter of ∼4.2 nm, was synthesized by using a low-temperature nonsurfactant hydrothermal route, employing tartaric acid as a templating agent. Gold additions from 0.5 to 2 wt% were incorporated, either during the hydrothermal process or by postsynthesis wet impregnation. Compared to the impregnation-prepared samples, the samples synthesized hydrothermally contained smaller-size (≤1 nm gold clusters occluded in the pores of the host matrix. Whereas CO2 and H2O were the main reaction products in UV-assisted vapor-phase oxidation of acetone using these catalysts, C2H6 and HCO2CH3 were also produced for higher acetone concentrations in air. The conversion of acetone was found to increase with decrease in the size of both TiO2 and gold particles. In situ IR spectroscopy revealed that titania and gold particles serve as independent adsorption and reaction sites for acetone and oxygen molecules. Acetone molecules adsorb exclusively at TiO2 surface, giving rise to a strongly adsorbed (condensed state as well as to the formation of formate- and methyl formate-type surface species. Hydroxyl groups at titania surface participate directly in these adsorption steps. Nanosize gold particles, on the other hand, were primarily responsible for the adsorption and activation of oxygen molecules. Mechanistic aspects of the photochemical processes are discussed on the basis of these observations.

  15. Development of Novel active transport membrane devices. Phase I. Final report, 31 October 1988--31 January 1994

    Energy Technology Data Exchange (ETDEWEB)

    Laciak, D.V.; Quinn, R.; Choe, G.S.; Cook, P.J.; Tsai, Fu-Jya

    1994-08-01

    The main objective of this program was to identify and develop a technique for fabricating Active Transport Materials (ATM) into lab-scale membrane devices. Air Products met this objective by applying thin film, multilayer fabrication techniques to support the AT material on a substrate membrane. In Phase IA, spiral-wound hollow fiber membrane modules were fabricated and evaluated. These nonoptimized devices were used to demonstrate the AT-based separation of carbon dioxide from methane, hydrogen sulfide from methane, and ammonia from hydrogen. It was determined that a need exists for a more cost efficient and less energy intensive process for upgrading subquality natural gas. Air Products estimated the effectiveness of ATM for this application and concluded that an optimized ATM system could compete effectively with both conventional acid gas scrubbing technology and current membrane technology. In addition, the optimized ATM system would have lower methane loss and consume less energy than current alternative processes. Air Products made significant progress toward the ultimate goal of commercializing an advanced membrane for upgrading subquality natural gas. The laboratory program focused on developing a high performance hollow fiber substrate and fabricating and evaluating ATM-coated lab-scale hollow fiber membrane modules. Selection criteria for hollow fiber composite membrane supports were developed and used to evaluate candidate polymer compositions. A poly(amide-imide), PAI, was identified for further study. Conditions were identified which produced microporous PAI support membrane with tunable surface porosity in the range 100-1000{Angstrom}. The support fibers exhibited good hydrocarbon resistance and acceptable tensile strength though a higher elongation may ultimately be desirable. ATM materials were coated onto commercial and PAI substrate fiber. Modules containing 1-50 fibers were evaluated for permselectivity, pressure stability, and lifetime.

  16. Adsorption characteristics of trichloroethylene and 1,1,1-trichloroethane onto activated carbon fiber in gaseous phase

    Energy Technology Data Exchange (ETDEWEB)

    Tanada, Seiki; Nakamura, Takeo; Xiaohong, Ma; Higuchi, Toshikazu; Shinoda, Sanji [Kinki Univ., Osaka (Japan)

    1992-07-01

    Trichloroethylene (TCE) and 1,1,1-trichloroethane (methylchloroform:MC) are major volatile chlorinated hydrocarbons, and the production amounts of these compounds run up to about 80,000-100,000 tons a year in Japan. TCE and MC were observed in groundwater in Japan as well as in the United States, so that the environmental contamination by these compounds became a serious problem. TCE and MC cause vertigo, headache, drunkenness and fatigue depending on central nervous system depress, and also liver or kidney lesion by inhalation as general toxicities. For prevention of the poisoning to workers, the permissible concentrations of TCE and MC vapors in work area have been set at 50ppm and 200ppm, respectively by Japan Association of Industrial Health. In the United States, those values are set at 100ppm and 350ppm by American Conference of Governmental Industrial Hygienists, respectively. In addition, TCE is considered to be carcinogenic because it causes liver cancer in mice. Furthermore, MC is considered to destroy the Ozone Layer. Though it is presumed that 40-70% of used TCE and MC in factories is exhausted to the atmosphere, there is no regulation now concerning the exhaustion of TCE and MC to the atmosphere. So that regards should be paid to the intake of TCE and MC from the atmosphere as well as from drinking water. In this paper, we studied the adsorption removal of TCE and MC by activated carbon fibers (ACFs) in gaseous phase pointing to the prevention against TCE and MC diffusion to the atmosphere and inhalation to workers. 9 refs., 3 figs., 2 tabs.

  17. Effects of Ni doping on photocatalytic activity of TiO2 thin films prepared by liquid phase deposition technique

    Indian Academy of Sciences (India)

    Noor Shahina Begum; H M Farveez Ahmed; K R Gunashekar

    2008-10-01

    The TiO2 thin films doped by Ni uniformly and non-uniformly were prepared on glass substrate from an aqueous solution of ammonium hexa-fluoro titanate and NiF2 by liquid phase deposition technique. The addition of boric acid as an – scavenger will shift the equilibrium to one side and thereby deposition of the film is progressed. The rate of the reaction and the nature of deposition depend on growing time and temperature. The resultant films were characterized by XRD, EDAX, UV and SEM. The result shows that the deposited films have amorphous background, which becomes crystalline at 500°C. The EDAX data confirms the existence of Ni atoms in TiO2 matrix. XRD analysis reveals the peaks corresponding to Ni but no peak of crystalline NiO was found. The transmittance spectra of Ni uniformly and non-uniformly doped TiO2 thin films show `blue shift and red shift’, respectively. Ni-doped TiO2 thin films can be used as photocatalyst for the photodegradation of methyl orange dye. It was found that, organic dye undergoes degradation efficiently in presence of non-uniformly Ni-doped TiO2 thin films when compared to uniformly doped films and pure TiO2 films under visible light. The photocatalytic activity increases with increase in the concentration of Ni in case of nonuniformly doped thin films but decreases with the concentration when uniformly doped thin films were used.

  18. Medical relief activities conducted by Nippon Medical School in the acute phase of the Great East Japan Earthquake 2011.

    Science.gov (United States)

    Fuse, Akira; Shuto, Yuki; Ando, Fumihiko; Shibata, Masafumi; Watanabe, Akihiro; Onda, Hidetaka; Masuno, Tomohiko; Yokota, Hiroyuki

    2011-01-01

    At 14:46 on March 11, 2011, the Great East Japan Earthquake and tsunami occurred off the coast of Honshu, Japan. In the acute phase of this catastrophe, one of our teams was deployed as a Tokyo Disaster Medical Assistance Team (DMAT) to Kudan Kaikan in Tokyo, where the ceiling of a large hall had partially collapsed as the result of the earthquake, to conduct triage at the scene: 6 casualties were assigned to the red category (immediate), which included 1 case of cardiopulmonary arrest and 1 of flail chest; 8 casualties in the yellow category (delayed); and 22 casualties in the green category (minor). One severely injured person was transported to our hospital. Separately, our medical team was deployed to Miyagi 2 hours after the earthquake in our multipurpose medical vehicle as part of Japan DMAT (J-DMAT). We were the first DMAT from the metropolitan area to arrive, but we were unable to start medical relief activities because the information infrastructure had been destroyed and no specific information had yet reached the local headquarters. Early next morning, J-DMAT decided to support Sendai Medical Center and search and rescue efforts in the affected area and to establish a staging care unit at Camp Kasuminome of the Japan Self-Defense Force. Our team joined others to establish the staging care unit. Because information was still confused until day 3 of the disaster and we could not adequately grasp onsite medical needs, our J-DMAT decided to provide onsite support at Ishinomaki Red Cross Hospital, a disaster base hospital, and relay information about its needs to the local J-DMAT headquarters. Although our medical relief teams were deployed as quickly as possible, we could not begin medical relief activities immediately owing to the severely damaged information infrastructure. Only satellite mobile phones could be operated, and information on the number of casualties and the severity of shortages of lifeline services could be obtained only through a "go and

  19. EUROPEAN contribution to the design and R and D activities in view of the start of the ITER construction phase

    International Nuclear Information System (INIS)

    The European effort in supporting the ITER design and R and D programme was maintained at a considerable level (about 70 M Euro/year in 2005 and 2006) in order to be ready to start the construction phase as soon as the ITER site is decided and the ITER Team is nominated. The main objectives of the activities performed in 2005 and 2006 are: (a) To continue the design and R and D effort towards the ITER procurement requirements in close collaboration with the ITER International Team. (b) To continue and complete manufacturing R and D to determine the most technically and cost effective manufacturing methods of the ITER components to be built in Europe. (c) To launch or to continue the preparation of the new facilities needed during ITER construction (DIPOLE, HELOKA, DTP-2, ECRH Test Facility, Fatigue Testing Facility). (d) To support the European site preparation process through an appropriate organization. (e) To develop the capabilities of the EU Associations in preparation of the procurement of ITER systems in the Heating and Current Drive and Diagnostic areas. (f) To maintain support to EU Industries in the fusion related work. The main achievements in the design and R and D have been: Divertor - small, medium and full-scale prototypes have been successfully tested at heat flux above the ITER requirements; Shield modules - alternative fabrication techniques are been developed to increase reliability, competition among industries and decrease fabrication costs; Vacuum Vessel - different welding techniques and distortion prediction models have been investigated; Magnets - advanced Nb3Sn strands and 70 kA high temperature superconductor current leads have been developed and tested exceeding the ITER requirements; Test Blanket Modules - the design was completed; manufacturing processes using EUROFER are developed; Fuel Cycle - extensive and successful tests were performed with half size torus exhaust model cryopump; ICRF - design work of the antenna array is being

  20. Desiccant-Based Combined Systems: Integrated Active Desiccant Rooftop Hybrid System Development and Testing Final Report- Phase 4

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, J

    2005-05-06

    This report summarizes the results of a research and development (R&D) program to design and optimize an active desiccant-vapor compression hybrid rooftop system. The primary objective was to combine the strengths of both technologies to produce a compact, high-performing, energy-efficient system that could accommodate any percentage of outdoor air and deliver essentially any required combination of temperature and humidity, or sensible heat ratio (SHR). In doing so, such a product would address the significant challenges imposed on the performance capabilities of conventional packaged rooftop equipment by standards 62 and 90.1 of the American Society of Heating, Refrigerating and Air-Conditioning Engineers. The body of work completed as part of this program built upon previous R&D efforts supported by the U.S. Department of Energy and summarized by the Phase 3b report ''Active Desiccant Dehumidification Module Integration with Rooftop Packaged HVAC Units'' (Fischer and Sand 2002), in addition to Fischer, Hallstrom, and Sand 2000; Fischer 2000; and Fischer and Sand 2004. All initial design objectives established for this development program were successfully achieved. The performance flexibility desired was accomplished by a down-sized active desiccant wheel that processes only a portion of the supply airflow, which is pre-conditioned by a novel vapor compression cycle. Variable-speed compressors are used to deliver the capacity control required by a system handling a high percentage of outdoor air. An integrated direct digital control system allows for control capabilities not generally offered by conventional packaged rooftop systems. A 3000-cfm prototype system was constructed and tested in the SEMCO engineering test laboratory in Columbia, MO, and was found to operate in an energy-efficient fashion relative to more conventional systems. Most important, the system offered the capability to independently control the supply air temperature and

  1. A subset of cancer cell lines is acutely sensitive to the Chk1 inhibitor MK-8776 as monotherapy due to CDK2 activation in S phase.

    Science.gov (United States)

    Sakurikar, Nandini; Thompson, Ruth; Montano, Ryan; Eastman, Alan

    2016-01-12

    DNA damage activates Checkpoint kinase 1 (Chk1) to halt cell cycle progression thereby preventing further DNA replication and mitosis until the damage has been repaired. Consequently, Chk1 inhibitors have emerged as promising anticancer therapeutics in combination with DNA damaging drugs, but their single agent activity also provides a novel approach that may be particularly effective in a subset of patients. From analysis of a large panel of cell lines, we demonstrate that 15% are very sensitive to the Chk1 inhibitor MK-8776. Upon inhibition of Chk1, sensitive cells rapidly accumulate DNA double-strand breaks in S phase in a CDK2- and cyclin A-dependent manner. In contrast, resistant cells can continue to grow for at least 7 days despite continued inhibition of Chk1. Resistance can be circumvented by inhibiting Wee1 kinase and thereby directly activating CDK2. Hence, sensitivity to Chk1 inhibition is regulated upstream of CDK2 and correlates with accumulation of CDC25A. We conclude that cells poorly tolerate CDK2 activity in S phase and that a major function of Chk1 is to ensure it remains inactive. Indeed, inhibitors of CDK1 and CDK2 arrest cells in G1 or G2, respectively, but do not prevent progression through S phase demonstrating that neither kinase is required for S phase progression. Inappropriate activation of CDK2 in S phase underlies the sensitivity of a subset of cell lines to Chk1 inhibitors, and this may provide a novel therapeutic opportunity for appropriately stratified patients. PMID:26595527

  2. Arginine in α-defensins: differential effects on bactericidal activity correspond to geometry of membrane curvature generation and peptide-lipid phase behavior.

    Science.gov (United States)

    Schmidt, Nathan W; Tai, Kenneth P; Kamdar, Karishma; Mishra, Abhijit; Lai, Ghee Hwee; Zhao, Kun; Ouellette, André J; Wong, Gerard C L

    2012-06-22

    The conserved tridisulfide array of the α-defensin family imposes a common triple-stranded β-sheet topology on peptides that may have highly diverse primary structures, resulting in differential outcomes after targeted mutagenesis. In mouse cryptdin-4 (Crp4) and rhesus myeloid α-defensin-4 (RMAD4), complete substitutions of Arg with Lys affect bactericidal peptide activity very differently. Lys-for-Arg mutagenesis attenuates Crp4, but RMAD4 activity remains mostly unchanged. Here, we show that the differential biological effect of Lys-for-Arg replacements can be understood by the distinct phase behavior of the experimental peptide-lipid system. In Crp4, small-angle x-ray scattering analyses showed that Arg-to-Lys replacements shifted the induced nanoporous phases to a different range of lipid compositions compared with the Arg-rich native peptide, consistent with the attenuation of bactericidal activity by Lys-for-Arg mutations. In contrast, such phases generated by RMAD4 were largely unchanged. The concordance between small-angle x-ray scattering measurements and biological activity provides evidence that specific types of α-defensin-induced membrane curvature-generating tendencies correspond directly to bactericidal activity via membrane destabilization.

  3. Design of a Four-Branch LCL-Type Grid-Connecting Interface for a Three-Phase, Four-Leg Active Power Filter

    Directory of Open Access Journals (Sweden)

    Wu Cao

    2015-02-01

    Full Text Available Compared with the three-phase, two-split-capacitor active power filter (3P2C-APF, the three-phase, four-leg active power filter (3P4L-APF has been widely used in three-phase, four-wire grid utility for power quality control due to its numerous advantages, such as higher current output capability, particularly in phase N, lower current and easier voltage control on the DC-side. However, designing the grid-connecting interface, which is between the voltage source converter (VSC and grid utility, is rather difficult due to the higher requirement for current ripple filtering in phase N, cross-coupling in four phases and lack of relevant design methodology and specification. In this paper, a four-branch LCL-type (4B-LCL grid-connecting interface is proposed for 3P4L-APF, which features better current ripple filtering performance without decreasing the current output capability in all phases. First, this paper describes the mathematical models of 4B-LCL in the fully-complex-vector form from the zero and non-zero sequence perspective, resulting in two independent and uniform equivalent circuits without cross coupling terms. Then, the 4B-LCL parameter design method based on the most comprehensive performance index is proposed, including three main stages as the specification: performance index requirement determination, fulfillment of that requirement, and verification. Finally, the validity and effectiveness of the proposed design are proven by the simulated and experimental results of a 3P4L-APF with 4B-LCL.

  4. In Vivo Antiprotozoal Activity of the Chloroform Extract from Carica papaya Seeds against Amastigote Stage of Trypanosoma cruzi during Indeterminate and Chronic Phase of Infection

    Directory of Open Access Journals (Sweden)

    Matilde Jimenez-Coello

    2014-01-01

    Full Text Available In order to evaluate the antiprotozoal activity of the chloroform extract of Carica papaya seeds during the subacute and chronic phase of infection of Trypanosoma cruzi, doses of 50 and 75 mg/kg were evaluated during the subacute phase, including a mixture of their main components (oleic, palmitic, and stearic acids. Subsequently, doses of 50 and 75 mg/kg in mice during the chronic phase of infection (100 dpi were also evaluated. It was found that chloroform extract was able to reduce the amastigote nests numbers during the subacute phase in 55.5 and 69.7% (P > 0.05 as well as in 56.45% in animals treated with the mixture of fatty acids. Moreover, the experimental groups treated with 50 and 75 mg/kg during the chronic phase of the infection showed a significant reduction of 46.8 and 53.13% respectively (P < 0.05. It is recommended to carry out more studies to determine if higher doses of chloroformic extract or its administration in combination with other antichagasic drugs allows a better response over the intracellular stage of T. cruzi in infected animal models and determine if the chloroform extract of C. papaya could be considered as an alternative for treatment during the indeterminate and chronic phase of the infection.

  5. Estimation of activation energy for electroporation and pore growth rate in liquid crystalline and gel phases of lipid bilayers using molecular dynamics simulations.

    Science.gov (United States)

    Majhi, Amit Kumar; Kanchi, Subbarao; Venkataraman, V; Ayappa, K G; Maiti, Prabal K

    2015-11-28

    Molecular dynamics simulations of electroporation in POPC and DPPC lipid bilayers have been carried out at different temperatures ranging from 230 K to 350 K for varying electric fields. The dynamics of pore formation, including threshold field, pore initiation time, pore growth rate, and pore closure rate after the field is switched off, was studied in both the gel and liquid crystalline (Lα) phases of the bilayers. Using an Arrhenius model of pore initiation kinetics, the activation energy for pore opening was estimated to be 25.6 kJ mol(-1) and 32.6 kJ mol(-1) in the Lα phase of POPC and DPPC lipids respectively at a field strength of 0.32 V nm(-1). The activation energy decreases to 24.2 kJ mol(-1) and 23.7 kJ mol(-1) respectively at a higher field strength of 1.1 V nm(-1). At temperatures below the melting point, the activation energy in the gel phase of POPC and DPPC increases to 28.8 kJ mol(-1) and 34.4 kJ mol(-1) respectively at the same field of 1.1 V nm(-1). The pore closing time was found to be higher in the gel than in the Lα phase. The pore growth rate increases linearly with temperature and quadratically with field, consistent with viscosity limited growth models. PMID:26372335

  6. Phase transformations during HLnTiO{sub 4} (Ln=La, Nd) thermolysis and photocatalytic activity of obtained compounds

    Energy Technology Data Exchange (ETDEWEB)

    Silyukov, Oleg I., E-mail: olegsilyukov@yandex.ru; Abdulaeva, Liliia D.; Burovikhina, Alena A.; Rodionov, Ivan A.; Zvereva, Irina A.

    2015-03-15

    Layered HLnTiO{sub 4} (Ln=La, Nd) compounds belonging to Ruddlesden–Popper phases were found to form partially hydrated compounds Ln{sub 2}Ti{sub 2}O{sub 7}·xH{sub 2}O during thermal dehydration as well as defect oxides Ln{sub 2}□Ti{sub 2}O{sub 7} as final products. Further heating of metastable defect Ln{sub 2}□Ti{sub 2}O{sub 7} substances leads to the formation of pyrochlore-type oxides Ln{sub 2}Ti{sub 2}O{sub 7} {sub (p)}, with subsequent transformation under higher temperatures to stable layered 110-type perovskites Ln{sub 2}Ti{sub 2}O{sub 7}. The occurring structure transformations lead to an increase of photocatalytic activity in the order of HLnTiO{sub 4}activity in the order of HLnTiO{sub 4}activity of all obtained compounds. The hydrogen evolution rate increased in the course of the structure changes during thermolysis.

  7. Solar Energetic Particle Events at the Rise Phase of the 23rd Solar Activity Cycle Registered aboard the Spacecraft "INTERBALL-2"

    Indian Academy of Sciences (India)

    Vladislav Timofeev

    2000-09-01

    The experiment with 10K-80 aboard the INTER-BALL-2 (which detects protons with energies > 7 , 27-41, 41-58, 58-88, 88-180 and 180-300 MeV) registered six events of the solar energetic particle (SEP) increase. These events are during the initial rise phase of the 23rd solar activity cycle. Solar flares with the SEP generation are accompanied by coronal mass ejection (CME). Here we analyze the dynamics of the differential energy spectrum at different phases of the SEP increase.

  8. Synergy in lipofection by cationic lipid mixtures: Superior activity at the gel-liquid crystalline phase transition

    OpenAIRE

    Koynova, Rumiana; Wang, Li; MacDonald, Robert C.

    2007-01-01

    Some mixtures of two cationic lipids including phospholipid compounds (O-ethylphosphatidylcholines), as well as common, commercially available cationic lipids, such as dimethylammonium bromides and trimethylammonium propanes, deliver therapeutic DNA considerably more efficiently than do the separate molecules. In an effort to rationalize this widespread “mixture synergism”, we examined the phase behavior of the cationic lipid mixtures and constructed their binary phase diagrams. Among a group...

  9. STAT3 Activation in Skeletal Muscle Links Muscle Wasting and the Acute Phase Response in Cancer Cachexia

    OpenAIRE

    Andrea Bonetto; Tufan Aydogdu; Noelia Kunzevitzky; Guttridge, Denis C.; Sawsan Khuri; Koniaris, Leonidas G.; Teresa A Zimmers

    2011-01-01

    BACKGROUND: Cachexia, or weight loss despite adequate nutrition, significantly impairs quality of life and response to therapy in cancer patients. In cancer patients, skeletal muscle wasting, weight loss and mortality are all positively associated with increased serum cytokines, particularly Interleukin-6 (IL-6), and the presence of the acute phase response. Acute phase proteins, including fibrinogen and serum amyloid A (SAA) are synthesized by hepatocytes in response to IL-6 as part of the i...

  10. Phase space representation of neutron monitor count rate and atmospheric electric field in relation to solar activity in cycles 21 and 22

    Science.gov (United States)

    Silva, H. G.; Lopes, I.

    2016-07-01

    Heliospheric modulation of galactic cosmic rays links solar cycle activity with neutron monitor count rate on earth. A less direct relation holds between neutron monitor count rate and atmospheric electric field because different atmospheric processes, including fluctuations in the ionosphere, are involved. Although a full quantitative model is still lacking, this link is supported by solid statistical evidence. Thus, a connection between the solar cycle activity and atmospheric electric field is expected. To gain a deeper insight into these relations, sunspot area (NOAA, USA), neutron monitor count rate (Climax, Colorado, USA), and atmospheric electric field (Lisbon, Portugal) are presented here in a phase space representation. The period considered covers two solar cycles (21, 22) and extends from 1978 to 1990. Two solar maxima were observed in this dataset, one in 1979 and another in 1989, as well as one solar minimum in 1986. Two main observations of the present study were: (1) similar short-term topological features of the phase space representations of the three variables, (2) a long-term phase space radius synchronization between the solar cycle activity, neutron monitor count rate, and potential gradient (confirmed by absolute correlation values above ~0.8). Finally, the methodology proposed here can be used for obtaining the relations between other atmospheric parameters (e.g., solar radiation) and solar cycle activity.

  11. Study on Relationship between Microstructure of Active Phase and HDS Performance of Sulifded Ni-Mo Catalysts:Effect of Metal Loading

    Institute of Scientific and Technical Information of China (English)

    Guo Rong; Shen Benxian; Fang Xiangchen; Sun Jin; Peng Chong; Cui Xiaoli

    2014-01-01

    Six Ni-Mo catalysts with different metal contents were prepared and characterized by N2 adsorption and X-ray diffractometry. The active phase microstructure of these catalysts was examined by the Raman spectroscopy, temperature-programmed reduction (TPR), X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy. Hydrodesulfurization (HDS) activity of catalyst samples were analyzed in a lfow ifxed-bed microreactor. The sulifdation degree of Mo and the length of the MoS2 slab slightly increased with the amount of metal loaded following sulifdation. This small change is attributed to polymolybdate species observed in all the oxidized catalysts. Weak metal-support interactions, as determined by the TPR technique, increased the NiSx sulifdation phase and MoS2 slab stacking. The HDS activity of the catalyst samples increased with the number of active sites. For high metal loading catalysts, their HDS activity was nearly identical because the sulfur atoms cannot easily approach active sites. This change is caused by the large number of stacked layers in the MoS2 slabs as well as the decrease in the speciifc surface area and pore volume of the catalyst samples with an increasing metal loading.

  12. Behavior of bowhead whales of the Davis Strait and Bering/Beaufort stocks versus regional differences in human activities. Final report on Phase 2

    International Nuclear Information System (INIS)

    The objectives were to determine (1) whether there are differences in behavior between the Bering/Chukchi/Beaufort and the Davis Strait/Baffin Bay populations and (2), if so, whether the differences might be attributable to the long-term cumulative effects of exposure to the presumed greater amount of human activity in the former area. Phase 1 showed that there are some differences in behavior. The Phase 2 report documents the relative amounts of human activity in the two areas in 1974-86, and evaluates whether regional differences in whale behavior and in human activities may be related. Activities considered include bowhead hunting and other subsistence activities, commercial fishing and shipping, marine seismic exploration, offshore oil exploration, and low-level aircraft flights. Bering/Beaufort bowheads were subjected to at least 3-5 times as much human activity in 1974-86. Most differences in behavior between the two stocks were better explained by environmental or biological factors than by disturbance. However, for bowheads migrating in autumn, regional differences in behavior may be related to the whaling that occurs in the Beaufort Sea in autumn

  13. Sinorhizobium meliloti sigma factors RpoE1 and RpoE4 are activated in stationary phase in response to sulfite.

    Directory of Open Access Journals (Sweden)

    Bénédicte Bastiat

    Full Text Available Rhizobia are soil bacteria able to establish a nitrogen-fixing symbiosis with legume plants. Both in soil and in planta, rhizobia spend non-growing periods resembling the stationary phase of in vitro-cultured bacteria. The primary objective of this work was to better characterize gene regulation in this biologically relevant growth stage in Sinorhizobium meliloti. By a tap-tag/mass spectrometry approach, we identified five sigma factors co-purifying with the RNA polymerase in stationary phase: the general stress response regulator RpoE2, the heat shock sigma factor RpoH2, and three extra-cytoplasmic function sigma factors (RpoE1, RpoE3 and RpoE4 belonging to the poorly characterized ECF26 subgroup. We then showed that RpoE1 and RpoE4 i are activated upon metabolism of sulfite-generating compounds (thiosulfate and taurine, ii display overlapping regulatory activities, iii govern a dedicated sulfite response by controlling expression of the sulfite dehydrogenase SorT, iv are activated in stationary phase, likely as a result of endogenous sulfite generation during bacterial growth. We showed that SorT is required for optimal growth of S. meliloti in the presence of sulfite, suggesting that the response governed by RpoE1 and RpoE4 may be advantageous for bacteria in stationary phase either by providing a sulfite detoxification function or by contributing to energy production through sulfite respiration. This paper therefore reports the first characterization of ECF26 sigma factors, the first description of sigma factors involved in control of sulphur metabolism, and the first indication that endogenous sulfite may act as a signal for regulation of gene expression upon entry of bacteria in stationary phase.

  14. Water-quality data-collection activities in Colorado and Ohio; Phase II, Evaluation of 1984 field and laboratory quality-assurance practices

    Science.gov (United States)

    Childress, C.J.; Chaney, T.M.; Myers, Donna; Norris, J.M.; Hren, Janet

    1987-01-01

    Serious questions have been raised by Congress about the usefulness of water quality data for addressing issues of regional and national scope and, especially, for characterizing the current quality of the Nation 's streams and groundwater. In response, the U.S. Geological Survey conducted a pilot study in Colorado and Ohio to: (1) determine the characteristics of current (1984) water quality data collection activities of Federal, regional, State, and local agencies, and academic institutions; and (2) determine how well the data from these activities, collected for various purposes and using different procedures, can be used to improve the ability to answer major broad scope questions, such as: what are (or were) natural or near-natural water quality conditions; what are existing water quality conditions; and, how water quality has changed and how the changes relate to human activities. Colorado and Ohio were chosen for the pilot study largely because they represent regions with different types of water quality concerns and programs. The study has been divided into three phases, the objectives of which are: Phase I - Inventory water quality data collection programs, including costs, and identify those programs that met a set of broad criteria for producing data that are potentially appropriate for water quality assessments of regional and national scope. Phase II - Evaluate the quality assurance of field and laboratory procedures used in producing the data from programs that met the broad criteria of Phase I. Phase III - Compile the qualifying data and evaluate the adequacy of this data base for addressing selected water quality questions of regional and national scope. (Author 's abstract)

  15. Ocular toxoplasmosis: evaluation of lacrimal - specific secretory IgA levels in both patients with active and inactive phases of the disease

    Directory of Open Access Journals (Sweden)

    Luiz Felipe Lynch

    2011-08-01

    Full Text Available Ocular toxoplasmosis can result in recurrent uveitis. Studies have shown that a correlation between active ocular toxoplasmosis and the presence of anti-Toxoplasma gondii secretory IgA (SIgA in tears. This study compares anti-T. gondii SIgA levels in patients' tears during the acute and inactive phases of toxoplasmic uveitis. Twenty-nine positive tear specific SIgA for T. gondii patients with acute toxoplasmic uveitis were selected and were followed-up for at least two years, when the anti-T. gondii SIgA tears levels were determined. Specific SIgA for T. gondii was negative in 22 patients (75.86% and positive in seven patients (24.13% of whom six (85.7% were followed over three years. Average SIgA levels during the acute phase are 1.54 and decrease significantly to 0.72 (p = 0.0001 during the inactive phase of disease. Because anti-T. gondii SIgA in the tear is negative in 75.86% of patients after the acute phase of infection, T. gondii SIgA levels may be used as a complementary diagnostic marker for active ocular toxoplasmosis.

  16. Spatial Separation of Charge Carriers in In2O3-x(OH)y Nanocrystal Superstructures for Enhanced Gas-Phase Photocatalytic Activity.

    Science.gov (United States)

    He, Le; Wood, Thomas E; Wu, Bo; Dong, Yuchan; Hoch, Laura B; Reyes, Laura M; Wang, Di; Kübel, Christian; Qian, Chenxi; Jia, Jia; Liao, Kristine; O'Brien, Paul G; Sandhel, Amit; Loh, Joel Y Y; Szymanski, Paul; Kherani, Nazir P; Sum, Tze Chien; Mims, Charles A; Ozin, Geoffrey A

    2016-05-24

    The development of strategies for increasing the lifetime of photoexcited charge carriers in nanostructured metal oxide semiconductors is important for enhancing their photocatalytic activity. Intensive efforts have been made in tailoring the properties of the nanostructured photocatalysts through different ways, mainly including band-structure engineering, doping, catalyst-support interaction, and loading cocatalysts. In liquid-phase photocatalytic dye degradation and water splitting, it was recently found that nanocrystal superstructure based semiconductors exhibited improved spatial separation of photoexcited charge carriers and enhanced photocatalytic performance. Nevertheless, it remains unknown whether this strategy is applicable in gas-phase photocatalysis. Using porous indium oxide nanorods in catalyzing the reverse water-gas shift reaction as a model system, we demonstrate here that assembling semiconductor nanocrystals into superstructures can also promote gas-phase photocatalytic processes. Transient absorption studies prove that the improved activity is a result of prolonged photoexcited charge carrier lifetimes due to the charge transfer within the nanocrystal network comprising the nanorods. Our study reveals that the spatial charge separation within the nanocrystal networks could also benefit gas-phase photocatalysis and sheds light on the design principles of efficient nanocrystal superstructure based photocatalysts. PMID:27159793

  17. Review of quantitative phase-digital holographic microscopy: promising novel imaging technique to resolve neuronal network activity and identify cellular biomarkers of psychiatric disorders

    KAUST Repository

    Marquet, Pierre

    2014-09-22

    Quantitative phase microscopy (QPM) has recently emerged as a new powerful quantitative imaging technique well suited to noninvasively explore a transparent specimen with a nanometric axial sensitivity. In this review, we expose the recent developments of quantitative phase-digital holographic microscopy (QP-DHM). Quantitative phase-digital holographic microscopy (QP-DHM) represents an important and efficient quantitative phase method to explore cell structure and dynamics. In a second part, the most relevant QPM applications in the field of cell biology are summarized. A particular emphasis is placed on the original biological information, which can be derived from the quantitative phase signal. In a third part, recent applications obtained, with QP-DHM in the field of cellular neuroscience, namely the possibility to optically resolve neuronal network activity and spine dynamics, are presented. Furthermore, potential applications of QPM related to psychiatry through the identification of new and original cell biomarkers that, when combined with a range of other biomarkers, could significantly contribute to the determination of high risk developmental trajectories for psychiatric disorders, are discussed.

  18. Third harmonic frequency generation by type-I critically phase-matched LiB3O5 crystal by means of optically active quartz crystal.

    Science.gov (United States)

    Gapontsev, Valentin P; Tyrtyshnyy, Valentin A; Vershinin, Oleg I; Davydov, Boris L; Oulianov, Dmitri A

    2013-02-11

    We present a method of third harmonic generation at 355 nm by frequency mixing of fundamental and second harmonic radiation of an ytterbium nanosecond pulsed all-fiber laser in a type-I phase-matched LiB(3)O(5) (LBO) crystal where originally orthogonal polarization planes of the fundamental and second harmonic beams are aligned by an optically active quartz crystal. 8 W of ultraviolet light at 355 nm were achieved with 40% conversion efficiency from 1064 nm radiation. The conversion efficiency obtained in a type-I phase-matched LBO THG crystal was 1.6 times higher than the one achieved in a type-II LBO crystal at similar experimental conditions. In comparison to half-wave plates traditionally used for polarization alignment the optically active quartz crystal has much lower temperature dependence and requires simpler optical alignment. PMID:23481827

  19. Effects of the Number of Active Receiver Channels on the Sensitivity of a Reflector Antenna System with a Multi-Beam Wideband Phased Array Feed

    CERN Document Server

    Iupikov, O

    2016-01-01

    A method for accurate modeling of a reflector antenna system with a wideband phased array feed is presented and used to study the effects of the number of active antenna elements and associated receiving channels on the receiving sensitivity of the antenna system. Numerical results are shown for a practical design named APERTIF that is currently under developed at The Netherlands Institute for Radio Astronomy (ASTRON).

  20. Hydrolysis of cellobiose by β-glucosidase from Aspergillus niger in the presence of soil solid phases: minerals, biochar, and activated carbon

    OpenAIRE

    Lammirato, Carlo

    2012-01-01

    This study investigates the effects of different soil solid phases on the extracellular enzymatic hydrolysis of cellobiose to glucose. Montmorillonite, kaolinite, goethite and wood char did not adsorb cellobiose whereas they adsorbed 10, 70, 70, 99 % respectively of β-glucosidase from Aspergillus niger. The hydrolysis rate decreased with increasing enzyme adsorption; wood char, for instance, reduced it by 30 %. Activated carbon adsorbed almost 100 % of both cellobiose and β-glucosidase and in...

  1. Effects of Growth Phase and Temperature on σB Activity within a Listeria monocytogenes Population: Evidence for RsbV-Independent Activation of σB at Refrigeration Temperatures

    Directory of Open Access Journals (Sweden)

    Marta Utratna

    2014-01-01

    Full Text Available The alternative sigma factor σB of Listeria monocytogenes is responsible for regulating the transcription of many of the genes necessary for adaptation to both food-related stresses and to conditions found within the gastrointestinal tract of the host. The present study sought to investigate the influence of growth phase and temperature on the activation of σB within populations of L. monocytogenes EGD-e wild-type, ΔsigB, and ΔrsbV throughout growth at both 4°C and 37°C, using a reporter fusion that couples expression of EGFP to the strongly σB-dependent promoter of lmo2230. A similar σB activation pattern within the population was observed in wt-egfp at both temperatures, with the highest induction of σB occurring in the early exponential phase of growth when the fluorescent population rapidly increased, eventually reaching the maximum in early stationary phase. Interestingly, induction of σB activity was heterogeneous, with only a proportion of the cells in the wt-egfp population being fluorescent above the background autofluorescence level. Moreover, significant RsbV-independent activation of σB was observed during growth at 4°C. This result suggests that an alternative route to σB activation exists in the absence of RsbV, a finding that is not explained by the current model for σB regulation.

  2. Lanthanide-activated Na5Gd9F32 nanocrystals precipitated from a borosilicate glass: Phase-separation-controlled crystallization and optical property

    International Nuclear Information System (INIS)

    Highlights: • Na5Gd9F32 nanocrystals embedded glass ceramics were fabricated for the first time. • Such glass ceramics were achieved by phase-separation-controlled crystallization. • Elemental mapping evidenced the segregation of activators into the Na5Gd9F32 lattice. • Luminescent color could be tuned by controlling glass crystallization temperature. - Abstract: Lanthanide-activated cubic Na5Gd9F32 nanocrystals were precipitated from a borosilicate glass with a specifically designed composition. The precursor glass is already phase-separated after melt-quenching, which is beneficial to the realization of the controllable glass crystallization for affording desirable size, morphology and activator partition. Elemental mapping in the scanning transmission electron microscopy evidenced that the segregation of lanthanide ions into the Na5Gd9F32 lattice was in situ formed without the requirement of long-range ionic diffusion. Impressively, such fabricated glass ceramic co-doped with Yb3+/Er3+ ions exhibited intense upconversion luminescence, which was about 500 times higher than that of the precursor glass, and its luminescent color could be easily tuned from red to green by controlling glass crystallization temperature. It is anticipated that such phase-separation synthesis strategy with precise control over nanostructure of glass ceramics offer a great opportunity to design other highly transparent nanocomposites with a wide range of tunable optical properties

  3. An experimental indoor phasing system based on active optics using dispersed Hartmann sensing technology in the visible waveband

    International Nuclear Information System (INIS)

    A telescope with a larger primary mirror can collect much more light and resolve objects much better than one with a smaller mirror, and so the larger version is always pursued by astronomers and astronomical technicians. Instead of using a monolithic primary mirror, more and more large telescopes, which are currently being planned or in construction, have adopted a segmented primary mirror design. Therefore, how to sense and phase such a primary mirror is a key issue for the future of extremely large optical/infrared telescopes. The Dispersed Fringe Sensor (DFS), or Dispersed Hartmann Sensor (DHS), is a non-contact method using broadband point light sources and it can estimate the piston by the two-directional spectrum formed by the transmissive grating's dispersion and lenslet array. Thus it can implement the combination of co-focusing by Shack-Hartmann technology and phasing by dispersed fringe sensing technologies such as the template-mapping method and the Hartmann method. We introduce the successful design, construction and alignment of our dispersed Hartmann sensor together with its design principles and simulations. We also conduct many successful real phasing tests and phasing corrections in the visible waveband using our existing indoor segmented mirror optics platform. Finally, some conclusions are reached based on the test and correction of experimental results.

  4. Human retrosplenial cortex displays transient theta phase locking with medial temporal cortex prior to activation during autobiographical memory retrieval.

    Science.gov (United States)

    Foster, Brett L; Kaveh, Anthony; Dastjerdi, Mohammad; Miller, Kai J; Parvizi, Josef

    2013-06-19

    The involvement of retrosplenial cortex (RSC) in human autobiographical memory retrieval has been confirmed by functional brain imaging studies, and is supported by anatomical evidence of strong connectivity between the RSC and memory structures within the medial temporal lobe (MTL). However, electrophysiological investigations of the RSC and its interaction with the MTL have mostly remained limited to the rodent brain. Recently, we reported a selective increase of high-frequency broadband (HFB; 70-180 Hz) power within the human RSC during autobiographical retrieval, and a predominance of 3-5 Hz theta band oscillations within the RSC during the resting state. In the current study, we aimed to explore the temporal dynamics of theta band interaction between human RSC and MTL during autobiographical retrieval. Toward this aim, we obtained simultaneous recordings from the RSC and MTL in human subjects undergoing invasive electrophysiological monitoring, and quantified the strength of RSC-MTL theta band phase locking. We observed significant phase locking in the 3-4 Hz theta range between the RSC and the MTL during autobiographical retrieval. This theta band phase coupling was transient and peaked at a consistent latency before the peak of RSC HFB power across subjects. Control analyses confirmed that theta phase coupling between the RSC and MTL was not seen for other conditions studied, other sites of recording, or other frequency ranges of interest (1-20 Hz). Our findings provide the first evidence of theta band interaction between the human RSC and MTL during conditions of autobiographical retrieval.

  5. A Sun-Earth-Moon Activity to Develop Student Understanding of Lunar Phases and Frames of Reference

    Science.gov (United States)

    Ashmann, Scott

    2012-01-01

    The Moon is an ever-present subject of observation, and it is a recurring topic in the science curriculum from kindergarten's basic observations through graduate courses' mathematical analyses of its orbit. How do students come to comprehend Earth's nearest neighbor? What is needed for them to understand the lunar phases and other phenomena and…

  6. Disposal of chemical agents and munitions stored at Pueblo Depot Activity, Colorado. Final, Phase 1: Environmental report

    Energy Technology Data Exchange (ETDEWEB)

    Terry, J.W.; Blasing, T.J.; Ensminger, J.T.; Johnson, R.O.; Schexnayder, S.M.; Shor, J.T.; Staub, W.P.; Tolbert, V.R.; Zimmerman, G.P.

    1995-04-01

    Under the Chemical Stockpile Disposal Program (CSDP), the US Army proposes to dispose of lethal chemical agents and munitions stored at eight existing Army installations in the continental United States. In 1988, the US Army issued the final programmatic environmental impact statement (FPEIS) for the CSDP. The FPEIS and the subsequent Record of Decision (ROD) identified an on-site disposal process as the preferred method for destruction of the stockpile. That is, the FPEIS determined the environmentally preferred alternative to be on-site disposal in high-temperature incinerators, while the ROD selected this alternative for implementation as the preferred method for destruction of the stockpile. In this Phase I report, the overall CSDP decision regarding disposal of the PUDA Stockpile is subjected to further analyses, and its validity at PUDA is reviewed with newer, more detailed data than those providing the basis for the conclusions in the FPEIS. The findings of this Phase I report will be factored into the scope of a site-specific environmental impact statement to be prepared for the destruction of the PUDA stockpile. The focus of this Phase I report is on those data identified as having the potential to alter the Army`s previous decision regarding disposal of the PUDA stockpile; however, several other factors beyond the scope of this Phase I report must also be acknowledged to have the potential to change or modify the Army`s decisions regarding PUDA.

  7. Activity of toluene-degrading Pseudomonas putida in the early growth phase of a biofilm for waste gas treatment

    DEFF Research Database (Denmark)

    Pedersen, A.R.; Møller, S.; Molin, S.;

    1997-01-01

    A biological trickling filter for treatment of toluene-containing waste gas was studied. The overall kinetics of the biofilm growth was followed in the early growth phase. A rapid initial colonization took place during the first three days. The biofilm thickness increased exponentially, whereas t...

  8. An experimental indoor phasing system based on active optics using dispersed Hartmann sensing technology in the visible waveband

    Institute of Scientific and Technical Information of China (English)

    Yong Zhang; Gen-Rong Liu; Yue-Fei Wang; Ye-Ping Li; Ya-Jun Zhang; Liang Zhang; Yi-Zhong Zeng; Jie Zhang

    2011-01-01

    A telescope with a larger primary mirror can collect much more light and resolve objects much better than one with a smaller mirror,and so the larger version is always pursued by astronomers and astronomical technicians.Instead of using a monolithic primary mirror,more and more large telescopes,which are currently being planned or in construction,have adopted a segmented primary mirror design.Therefore,how to sense and phase such a primary mirror is a key issue for the future of extremely large optical/infrared telescopes.The Dispersed Fringe Sensor (DFS),or Dispersed Hartmann Sensor (DHS),is a non-contact method using broadband point light sources and it can estimate the piston by the two-directional spectrum formed by the transmissive grating's dispersion and lenslet array.Thus it can implement the combination of co-focusing by Shack-Hartmann technology and phasing by dispersed fringe sensing technologies such as the template-mapping method and the Hartmann method.We introduce the successful design,construction and alignment of our dispersed Hartmann sensor together with its design principles and simulations.We also conduct many successful real phasing tests and phasing corrections in the visible waveband using our existing indoor segmented mirror optics platform.Finally,some conclusions are reached based on the test and correction of experimental results.

  9. Experimental Testing and Model Validation of a Decoupled-Phase On-Load Tap Changer Transformer in an Active Network

    DEFF Research Database (Denmark)

    Zecchino, Antonio; Hu, Junjie; Coppo, Massimiliano;

    2016-01-01

    Due to the increasing penetration of single-phase small generation units and electric vehicles connected to distribution grids, system operators are facing challenges related to local unbalanced voltage rise or drop issues, which may lead to a violation of the allowed voltage band. To address...

  10. Deteriorated stress response in stationary-phase yeast: Sir2 and Yap1 are essential for Hsf1 activation by heat shock and oxidative stress, respectively.

    Directory of Open Access Journals (Sweden)

    Inbal Nussbaum

    Full Text Available Stationary-phase cultures have been used as an important model of aging, a complex process involving multiple pathways and signaling networks. However, the molecular processes underlying stress response of non-dividing cells are poorly understood, although deteriorated stress response is one of the hallmarks of aging. The budding yeast Saccharomyces cerevisiae is a valuable model organism to study the genetics of aging, because yeast ages within days and are amenable to genetic manipulations. As a unicellular organism, yeast has evolved robust systems to respond to environmental challenges. This response is orchestrated largely by the conserved transcription factor Hsf1, which in S. cerevisiae regulates expression of multiple genes in response to diverse stresses. Here we demonstrate that Hsf1 response to heat shock and oxidative stress deteriorates during yeast transition from exponential growth to stationary-phase, whereas Hsf1 activation by glucose starvation is maintained. Overexpressing Hsf1 does not significantly improve heat shock response, indicating that Hsf1 dwindling is not the major cause for Hsf1 attenuated response in stationary-phase yeast. Rather, factors that participate in Hsf1 activation appear to be compromised. We uncover two factors, Yap1 and Sir2, which discretely function in Hsf1 activation by oxidative stress and heat shock. In Δyap1 mutant, Hsf1 does not respond to oxidative stress, while in Δsir2 mutant, Hsf1 does not respond to heat shock. Moreover, excess Sir2 mimics the heat shock response. This role of the NAD+-dependent Sir2 is supported by our finding that supplementing NAD+ precursors improves Hsf1 heat shock response in stationary-phase yeast, especially when combined with expression of excess Sir2. Finally, the combination of excess Hsf1, excess Sir2 and NAD+ precursors rejuvenates the heat shock response.

  11. "Lunar Phases Project" as a Foundation for the Development of Innovative Inquiry Based ASTRO 101 Activities Utilizing Existing Concept Inventories as Assessment Tools

    Science.gov (United States)

    Mon, M. J.; Meyer, A. O.

    2012-08-01

    The cause and process of the lunar phases are difficult concepts for undergraduates and non-science majors to grasp. At Florida Gulf Coast University (FGCU) we have combined an inquiry-based instructional method (Mental Model Building) which can be more effective increasing students' conceptual understanding of the lunar phase cycle, together with the students' own observations. Undergraduate and non-science major students completed a hands-on project designed to integrate real observations, application of the scientific method, and Mental Model Building to connect the students' own observations to the Earth-Sun-Moon orientations responsible for their findings. Students' learning was assessed by administering the Lunar Phases Concept Inventory (developed by Rebecca S. Lindell and James P. Olsen, Southern Illinois University) before and after students completed the project, with positive results. We describe the methodology and activities utilized in our Lunar Phases Project, and propose their expansion to a variety of astronomical topics for undergraduate non-science majors and pre-service teachers. We emphasize developing and implementing new instructional strategies through the expansion of the Mental Model Building and similar pedagogical methodologies to develop innovative inquiry-based projects and activities in a variety of astronomical topics for undergraduate non-science majors and pre-service teachers. In order to meaningfully assess the new curriculum tools, we recommend utilizing already existing research-validated concept inventories specific to the astronomy content in the curriculum tools. These inventories can be analyzed to determine the conceptual learning gains achieved by the participating students and with further analysis can be used to refine portions of the activity under study.

  12. Alcohol and lithium have opposing effects on the period and phase of the behavioral free-running activity rhythm.

    Science.gov (United States)

    Nascimento, Nara F; Carlson, Karen N; Amaral, Danielle N; Logan, Ryan W; Seggio, Joseph A

    2015-06-01

    Bipolar patients have a high prevalence of comorbid alcohol use and abuse disorders, while chronic alcohol drinking may increase the presence and severity of certain symptoms of bipolar disorder. As such, there may be many individuals that are prescribed lithium to alleviate the manic symptoms of bipolar disorder, but also drink alcohol concurrently. In addition, both alcoholics and individuals with bipolar disorder often exhibit disruptions to their sleep-wake cycles and other circadian rhythms. Interestingly, both ethanol and lithium are known to alter both the period and the phase of free-running rhythms in mammals. While lithium is known to lengthen the period, ethanol seems to shorten the period and attenuate the responses to acute light pulses. Therefore, the present study aimed to determine whether ethanol and lithium have opposing effects on the circadian pacemaker when administered together. C57BL/6J mice were provided drinking solutions containing lithium, alcohol, or both, and their free-running rhythms along with their response to photic phase shifts were investigated. Mice treated with lithium displayed period lengthening, which was almost completely negated when ethanol was added. Moreover, ethanol significantly attenuated light-induced phase delays while the addition of lithium partially restored this response. These results indicate that alcohol and lithium have opposing effects on behavioral circadian rhythms. Individuals with bipolar disorder who are prescribed lithium and who drink alcohol might be inadvertently altering their sleep and circadian cycles, which may exacerbate their symptoms.

  13. Improvement of oxygen-containing functional groups on olive stones activated carbon by ozone and nitric acid for heavy metals removal from aqueous phase.

    Science.gov (United States)

    Bohli, Thouraya; Ouederni, Abdelmottaleb

    2016-08-01

    Recently, modification of surface structure of activated carbons in order to improve their adsorption performance toward especial pollutants has gained great interest. Oxygen-containing functional groups have been devoted as the main responsible for heavy metal binding on the activated carbon surface; their introduction or enhancement needs specific modification and impregnation methods. In the present work, olive stones activated carbon (COSAC) undergoes surface modifications in gaseous phase using ozone (O3) and in liquid phase using nitric acid (HNO3). The activated carbon samples were characterized using N2 adsorption-desorption isotherm, SEM, pHpzc, FTIR, and Boehm titration. The activated carbon parent (COSAC) has a high surface area of 1194 m(2)/g and shows a predominantly microporous structure. Oxidation treatments with nitric acid and ozone show a decrease in both specific surface area and micropore volumes, whereas these acidic treatments have led to a fixation of high amount of surface oxygen functional groups, thus making the carbon surface more hydrophilic. Activated carbon samples were used as an adsorbent matrix for the removal of Co(II), Ni(II), and Cu(II) heavy metal ions from aqueous solutions. Adsorption isotherms were obtained at 30 °C, and the data are well fitted to the Redlich-Peterson and Langmuir equation. Results show that oxidized COSACs, especially COSAC(HNO3), are capable to remove more Co(II), Cu(II), and Ni(II) from aqueous solution. Nitric acid-oxidized olive stones activated carbon was tested in its ability to remove metal ions from binary systems and results show an important maximum adsorbed amount as compared to single systems.

  14. Spectral analysis of ionospheric disturbances in the phase delay and radio signal amplitude at limb paths according to the COSMIC data in periods of solar activity

    Science.gov (United States)

    Shmakov, A. V.; Gorbunov, M. E.

    2016-07-01

    Based on more than 4500 sessions of radio transillumination of Earth's atmosphere along the satellite-atmosphere-satellite path obtained in the COSMIC experiment, the distribution along latitude and over local time of the spatial spectra of variations in the ionospheric phase delay and signal amplitude has been analyzed. The spatial spectra have been calculated for two height ranges, i.e., 60-80 and 80-100 km. In the phase signal spectrum within the height range 80-100 km, the second maximum in the vicinity of a frequency of 7-8 rad/km is clearly seen. Its diurnal and latitudinal behavior and its decrease towards high latitudes in both hemispheres can also be seen. In the height range of 60-80 km, this maximum is hardly observed. Although solar flares can lead to substantial local changes in the electron concentration, no substantial difference in the behavior of the spectral densities of the amplitude and phase delay at long limb paths was observed within these two height ranges on days of active and quiet sun. The latter fact makes it possible to develop a united algorithm of optimal ionospheric correction of the radio occultation data independent of solar activity.

  15. Self-propelled rods exhibit a novel phase-separated state characterized by the presence of active stresses and the ejection of polar clusters

    CERN Document Server

    Weitz, Sebastian; Peruani, Fernando

    2015-01-01

    We study collections of self-propelled rods (SPR) moving in two dimensions for packing fractions less than or equal to 0.3. We find that in the thermodynamical limit the SPR undergo a phase transition between a disordered gas and a novel phase-separated system state. Interestingly, (global) orientational order patterns -- contrary to what has been suggested -- vanish in this limit. In the found novel state, the SPR self-organize into a highly dynamical, high-density, compact region - which we call aggregate - which is surrounded by a disordered gas. Active stresses build inside aggregates as result of the combined effect of local orientational order and active forces. This leads to the most distinctive feature of these aggregates: constant ejection of polar clusters of SPR. This novel phase-separated state represents a novel state of matter characterized by large fluctuations in volume and shape, related to mass ejection, and exhibits positional as well as orientational local order. SPR systems display new ph...

  16. Characterization and use of high surface area activated carbons prepared from cane pith for liquid-phase adsorption

    International Nuclear Information System (INIS)

    Carbonaceous adsorbents with controllable surface areas were chemically activated with KOH at 780 deg. C from char that had been carbonized from cane pith at 450 deg. C. The pore properties including the BET surface area, pore volume, pore size distribution, and mean pore diameter of these activated carbons were characterized and derived using the t-plot method based on N2 adsorption isotherms. The activated cane pith carbons, with KOH/char ratios of 2-6, exhibited BET surface areas ranging from 912 to 2299 m2 g-1. The scanning electron microscopic (SEM) observations revealed that the surface morphology of honeycombed holes on all activated cane pith carbons was significantly influenced by the KOH/char ratio. The adsorption kinetics and equilibrium isotherms of acid blue 74, methylene blue, basic brown 1, p-nitrophenol, p-chlorophenol, p-cresol, and phenol from water at 30 deg. C on the activated carbons were studied. The adsorption kinetics were suitably described by a simplified kinetic model, the Elovich equation. All adsorption equilibrium isotherms were in agreement with the Langmuir equation, and were used to compare the covered area (S c/S p) of the activated carbons at different KOH/char ratios. The high-surface-area activated carbons were proven to be promising adsorbents for pollution control and for other applications

  17. Co-localization hypothesis: A mechanism for the intrapancreatic activation of digestive enzymes during the early phases of acute pancreatitis

    Institute of Scientific and Technical Information of China (English)

    Gijs JD van Acker; George Perides; Michael L Steer

    2006-01-01

    Acute pancreatitis is generally believed to be a disease in which the pancreas is injured by digestive enzymes that it normally produces. Most of the potentially harmful digestive enzymes produced by pancreatic acinar cells are synthesized and secreted as inactive zymogens which are normally activated only upon entry into the duodenum but, during the early stages of acute pancreatitis, those zymogens become prematurely activated within the pancreas and, presumably, that activation occurs within pancreatic acinar cells. The mechanisms responsible for intracellular activation of digestive enzyme zymogens have not been elucidated with certainty but, according to one widely recognized theory (the "co-localization hypothesis"), digestive enzyme zymogens are activated by lysosomal hydrolases when the two types of enzymes become co-localized within the same intracellular compartment. This review focuses on the evidence supporting the validity of the co-localization hypothesis as an explanation for digestive enzyme activation during the early stages of pancreatitis.The findings, summarized in this review, support the conclusion that co-localization of lysosomal hydrolases with digestive enzyme zymogens plays a critical role in permitting the intracellular activation of digestive enzymesthat leads to acinar cell injury and pancreatitis.

  18. Adaptive Fuzzy PID Based Control Strategy For 3Phase 4Wire Shunt Active Filter To Mitigate Current Harmonics Of Grid Interconnection Of Renewable Energy Based Distribution System

    Directory of Open Access Journals (Sweden)

    Kaleemullah

    2016-06-01

    Full Text Available This paper presents a new control strategy for controlling the shunt active power filter to compensate reactive power and to reduce the unwanted harmonics in the grid current. Shunt active filter act as a current source which is connected in parallel with a non-linear load and controlled to produce the required compensating current. The proposed control strategy is based on the fuzzy PID controller which is used for determining the reference compensating currents of the three-phase shunt active power filters. Simulations are carried out using MATLAB/SIMULINK to verify the performance of the proposed controller. The output shows the controller has fast dynamic response high accuracy of tracking DC voltage reference and robust to load parameters variations.

  19. High-Performance Harmonic Isolation and Load Voltage Regulation of the Three-Phase Series Active Filter Utilizing the Waveform Reconstruction Method

    DEFF Research Database (Denmark)

    Senturk, Osman Selcuk; Hava, Ahmet M.

    2009-01-01

    This paper develops a waveform reconstruction method (WRM) for high accuracy and bandwidth signal decomposition of voltage-harmonic-type three-phase diode rectifier load voltage into its harmonic and fundamental components, which are utilized in the series active filter (SAF) control algorithms....... The SAF-compensated system utilizing WRM provides highperformance load harmonic voltage isolation and load voltage regulation at steady-state and during transients compared to the system utilizing the synchronous reference-frame-based signal decomposition. In addition, reducing the line current sampling...... delay in the discrete-time implementation enhances the stability of the SAF. The simulations and experimental studies of a 10-kW three-phase SAF-compensated system prove the theory....

  20. Hydrogenation of nitriles on a well-characterized nickel surface: From surface science studies to liquid phase catalytic activity measurements

    Energy Technology Data Exchange (ETDEWEB)

    Gardin, D.E.

    1993-12-01

    Nitrile hydrogenation is the most commonly used method for preparing diverse amines. This thesis is aimed at the mechanism and factors affecting the performance of Ni-based catalysts in nitrile hydrogenations. Surface science techniques are used to study bonding of nitriles and amines to a Ni(111) surface and to identify surface intermediates. Liquid-phase hydrogenations of cyclohexene and 1-hexene on a Pt foil were carried out successfully. Finally, knowledge about the surface structure, surface chemical bond, dynamics of surface atoms (diffusion, growth), and reactivity of metal surfaces from solid-gas interface studies, is discussed.

  1. Silicide Induced Surface Defects in FePt nanoParticle fcc-to-fct Thermally Activated Phase Transition

    OpenAIRE

    Chen, S.; Lee, S. L.; André, P.

    2016-01-01

    Magnetic nanoparticles (MnPs) are relevant to a wide range of applications including high density information storage and magnetic resonance imaging to name but a few. Among the materials available to prepare MnPs, FePt is attracting growing attention. However, to harvest the strongest magnetic properties of FePt MnPs, a thermal annealing is often required to convert face-centered cubic as synthesized nPs into its tetragonal phase. Rarely addressed are the potential side effects of such treat...

  2. Desorption experiments and modeling of micropollutants on activated carbon in water phase: application to transient concentrations mitigation

    OpenAIRE

    Bourneuf, Séda; Jacob, Matthieu; Albasi, Claire; Sochard, Sabine; Richard, Romain; Manero, Marie-Hélène

    2016-01-01

    International audience Experimental studies and numerical modeling were conducted to assess the feasibility of a granular activated carbon column to buffer load variations of contaminants before wastewater treatment devices. Studies of cycles of adsorption, and more especially desorption, of methyldiethanolamine (MDEA) and 2,4-dimethylphenol (2,4-DMP) have been carried out on granular activated carbon (GAC). Dynamic variations of contaminants concentrations were run at several conditions o...

  3. Batch sorption dynamics and equilibrium for the removal of lead ions from aqueous phase using activated carbon developed from coffee residue activated with zinc chloride.

    Science.gov (United States)

    Boudrahem, F; Aissani-Benissad, F; Aït-Amar, H

    2009-07-01

    Lignocellulosic materials are good precursors for the production of activated carbon. In this work, coffee residue has been used as raw material in the preparation of powder activated carbon by the method of chemical activation with zinc chloride for the sorption of Pb(II) from dilute aqueous solutions. The influence of impregnation ratio (ZnCl2/coffee residue) on the physical and chemical properties of the prepared carbons was studied in order to optimize this parameter. The optimum experimental condition for preparing predominantly microporous activated carbons with high pore surface area (890 m2/g) and micropore volume (0.772 cm3/g) is an impregnation ratio of 100%. The developed activated carbon shows substantial capability to sorb lead(II) ions from aqueous solutions and for relative impregnation ratios of 75 and 100%, the maximum uptake is practically the same. Thus, 75% represents the optimal impregnation ratio. Batch experiments were conducted to study the effects of the main parameters such as contact time, initial concentration of Pb(II), solution pH, ionic strength and temperature. The maximum uptake of lead(II) at 25 degrees C was about 63 mg/g of adsorbent at pH 5.8, initial Pb(II) concentration of 10 mg/L, agitation speed of 200 rpm and ionic strength of 0.005 M. The kinetic data were fitted to the models of pseudo-first order and pseudo-second order, and follow closely the pseudo-second order model. Equilibrium sorption isotherms of Pb(II) were analyzed by the Langmuir, Freundlich and Temkin isotherm models. The Freundlich model gives a better fit than the others. Results from this study suggest that activated carbon produced from coffee residue is an effective adsorbent for the removal of lead from aqueous solutions and that ZnCl2 is a suitable activating agent for the preparation of high-porosity carbons. PMID:19447542

  4. Design of Automatic Testing System for Active Phased Array Antenna%有源相控阵天线自动测试系统设计

    Institute of Scientific and Technical Information of China (English)

    熊毅; 符伟; 钱林; 何诚; 陶成忠

    2012-01-01

    Aimed at multi-channel, large amount of testing data, low test efficiency in T/R module test of active phased array antenna, we designed an automatic test system for active phased array antenna, which adapts to testing large amount of T/R modules. The system controls VNA and gathers data from it via GPIB or ethernet and fully uses strong ability of modern computer for processing and analyzing data. It not only solves the problems of trouble diagnosis and automatic calibration of active phased array, but also improves the work efficiency and saves human cost. Results of actual application show that the test system works stably, and is easy to operate, it can meet the demands for measuring T/R module.%针对现代有源相控阵雷达天线T/R组件测试通路多、测试数据处理量大、测试效率低的特点,设计了一种适用于大规模T/R组件测试的有源相控阵天线自动测试系统.该系统设计通过GPIB接口或以太网对VNA(矢量网络分析仪)进行访问控制与数据采集,充分利用了现代计算机强大的数据处理与分析能力,不仅解决了有源相控阵天线故障诊断与自动校正问题,而且还极大地提高了工作效率,节约了人力成本.实际应用表明:该测试系统工作稳定,使用方便,能够充分满足T/R组件测试需要.

  5. Single-Step Fabrication Using a Phase Inversion Method of Poly(vinylidene fluoride) (PVDF) Activated Carbon Air Cathodes for Microbial Fuel Cells

    KAUST Repository

    Yang, Wulin

    2014-10-14

    Air cathodes used in microbial fuel cells (MFCs) need to have high catalytic activity for oxygen reduction, but they must also be easy to manufacture, inexpensive, and watertight. A simple one-step, phase inversion process was used here to construct an inexpensive MFC cathode using a poly(vinylidene fluoride) (PVDF) binder and an activated carbon catalyst. The phase inversion process enabled cathode preparation at room temperatures, without the need for additional heat treatment, and it produced for the first time a cathode that did not require a separate diffusion layer to prevent water leakage. MFCs using this new type of cathode produced a maximum power density of 1470 ± 50 mW m–2 with acetate as a substrate, and 230 ± 10 mW m–2 with domestic wastewater. These power densities were similar to those obtained using cathodes made using more expensive materials or more complex procedures, such as cathodes with a polytetrafluoroethylene (PTFE) binder and a poly(dimethylsiloxane) (PDMS) diffusion layer, or a Pt catalyst. Even though the PVDF cathodes did not have a diffusion layer, they withstood up to 1.22 ± 0.04 m of water head (∼12 kPa) without leakage, compared to 0.18 ± 0.02 m for cathodes made using PTFE binder and PDMS diffusion layer. The cost of PVDF and activated carbon ($3 m–2) was less than that of the stainless steel mesh current collector ($12 m–2). PVDF-based AC cathodes therefore are inexpensive, have excellent performance in terms of power and water leakage, and they can be easily manufactured using a single phase inversion process at room temperature.

  6. Motor patterns of the small intestine explained by phase-amplitude coupling of two pacemaker activities: the critical importance of propagation velocity.

    Science.gov (United States)

    Huizinga, Jan D; Parsons, Sean P; Chen, Ji-Hong; Pawelka, Andrew; Pistilli, Marc; Li, Chunpei; Yu, Yuanjie; Ye, Pengfei; Liu, Qing; Tong, Mengting; Zhu, Yong Fang; Wei, Defei

    2015-09-15

    Phase-amplitude coupling of two pacemaker activities of the small intestine, the omnipresent slow wave activity generated by interstitial cells of Cajal of the myenteric plexus (ICC-MP) and the stimulus-dependent rhythmic transient depolarizations generated by ICC of the deep muscular plexus (ICC-DMP), was recently hypothesized to underlie the orchestration of the segmentation motor pattern. The aim of the present study was to increase our understanding of phase-amplitude coupling through modeling. In particular the importance of propagation velocity of the ICC-DMP component was investigated. The outcome of the modeling was compared with motor patterns recorded from the rat or mouse intestine from which propagation velocities within the different patterns were measured. The results show that the classical segmentation motor pattern occurs when the ICC-DMP component has a low propagation velocity (velocity in the same order of magnitude as that of the slow wave activity (∼1 cm/s), cluster type propulsive activity occurs which is in fact the dominant propulsive activity of the intestine. Hence, the only difference between the generation of propagating cluster contractions and the Cannon-type segmentation motor pattern is the propagation velocity of the low-frequency component, the rhythmic transient depolarizations originating from the ICC-DMP. Importantly, the proposed mechanism explains why both motor patterns have distinct rhythmic waxing and waning of the amplitude of contractions. The hypothesis is brought forward that the velocity is modulated by neural regulation of gap junction conductance within the ICC-DMP network.

  7. Safety and pharmacodynamic effects of a pharmacological chaperone on α-galactosidase A activity and globotriaosylceramide clearance in Fabry disease: report from two phase 2 clinical studies

    Directory of Open Access Journals (Sweden)

    Germain Dominique P

    2012-11-01

    Full Text Available Abstract Background Fabry disease (FD is a genetic disorder resulting from deficiency of the lysosomal enzyme α-galactosidase A (α-Gal A, which leads to globotriaosylceramide (GL-3 accumulation in multiple tissues. We report on the safety and pharmacodynamics of migalastat hydrochloride, an investigational pharmacological chaperone given orally at 150 mg every-other-day. Methods Two open-label uncontrolled phase 2 studies of 12 and 24 weeks (NCT00283959 and NCT00283933 in 9 males with FD were combined. At multiple time points, α-Gal A activity and GL-3 levels were quantified in blood cells, kidney and skin. GL-3 levels were also evaluated through skin and renal histology. Results Compared to baseline, increased α-Gal A activity of at least 50% was demonstrated in blood, skin and kidney in 6 of 9 patients. Patients’ increased α-Gal A activities paralleled the α-Gal A increases observed in vitro in HEK-293 cells transfected with the corresponding mutant form of the enzyme. The same 6 patients who demonstrated increases of α-Gal A activity also had GL-3 reduction in skin, urine and/or kidney, and had α-Gal A mutations that responded in transfected cells incubated with the drug. The 3 patients who did not show a consistent response in vivo had α-Gal A mutations that did not respond to migalastat HCl in transfected cells. Migalastat HCl was well tolerated. Conclusions Migalastat HCl is a candidate pharmacological chaperone that provides a novel genotype-specific treatment for FD. It enhanced α-Gal A activity and resulted in GL-3 substrate decrease in patients with responsive GLA mutations. Phase 3 studies are ongoing. Trial registration Clinicaltrial.gov: NCT00283959 and NCT00283933

  8. From the powder to the honeycomb. A comparative study of the NSRefficiency and selectivity over Pt–CeZr based active phase

    OpenAIRE

    Masdrag, L; Courtois, X; Can, F.; Cartoixa, B; Raux, Stéphane; Frobert, Aranud; Duprez, D

    2015-01-01

    From the powder to the honeycomb. A comparative study of the NSR efficiency and selectivity over Pt-CeZr based active phase. Abstract The efficiency and the selectivity of a model platinum based catalyst supported on a modified ceria-zirconia oxide was evaluated in the NOx storage-reduction (NSR) process at four catalytic scales: powder, (0.5"x1.5") flow-through monolith (FTM) system, small size (1"x2") and full size (5.66"x10") catalysed Diesel Particulate Filter (DPF). The washcoating of th...

  9. Development of Spaceborne Deployable Active Phased Array Antennas%星载可展开有源相控阵天线结构的研究进展

    Institute of Scientific and Technical Information of China (English)

    王从思; 韩如冰; 王伟; 王猛; TU Qingsong; 平丽浩

    2016-01-01

    星载可展开有源相控阵天线作为空间通信、电子侦察、导航、环境监测等卫星系统的“眼睛”和“耳朵”,通过空间可展开结构实现较大的物理口径,利用有源相控阵体制实现独立控制多个点波束,克服了传统机械扫描天线的诸多缺点,已成为宇航领域的关键装备之一。总结星载有源相控阵天线发展历程,分析星载有源相控阵天线的结构形式、性能要求及应用情况,阐述国内外研究现状,并对其涉及的七项关键结构技术做了概要解析,探讨星载可展开有源相控阵天线结构领域的未来研究方向。%As the“eyes” and “ears” of the space communications, electronic countermeasures, navigation, environmental monitoring and other satellite systems, the spaceborne deployable active phased array antenna achieves a greater physical aperture through a deployable configuration, and implements the individual control of different spot beams using the electronic scan mode. It has been one of the key equipments in the areas of aerospace without the many drawbacks brought by the mechanical scan antennas. The development process of the spaceborne active phased array antennas is introduced. And the configuration styles, performance requirements and engineering applications of the spaceborne deployable active phased array antennas are presented. The international research statuses are described. At the same time, a concise analysis of the seven key technologies of antenna structure field is made. The develop trends of the spaceborne deployable active phased array antenna structural technologies are discussed.

  10. Photoelectrocatalytic activity of liquid phase deposited α-Fe{sub 2}O{sub 3} films under visible light illumination

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Man; Pu, Wenhong; Pan, Shichang [School of Environmental Science and Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan 430074 (China); Okoth, Otieno Kevin [School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan 430074 (China); Yang, Changzhu [School of Environmental Science and Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan 430074 (China); Zhang, Jingdong, E-mail: zhangjd@mail.hust.edu.cn [School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan 430074 (China)

    2015-11-05

    Liquid phase deposition (LPD) technique was employed to prepare α-Fe{sub 2}O{sub 3} films for photoelectrocatalytic degradation of pollutants. The obtained LPD films were characterized by various surface analysis techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and X-ray photoelectron spectroscopy (XPS). The results indicated that α-Fe{sub 2}O{sub 3} films with porous structure were successfully deposited on the titanium substrates by the LPD process. The UV–Visible diffuse reflectance spectroscopic (DRS) analysis showed that the obtained LPD α-Fe{sub 2}O{sub 3} film mainly absorbed visible light, which was advantageous to the utilization of solar energy. Under visible light illumination, the Fe{sub 2}O{sub 3} film electrodes exhibited sensitive photocurrent responses, which were affected by the calcination temperature. Consistent with the photocurrent analysis, the α-Fe{sub 2}O{sub 3} film calcined at 600 °C showed the best photoelectrocatalytic performance, and different organic pollutants such as methyl orange (MO) and p-nitrophenol (PNP) were effectively degraded over the LPD film electrode by photoelectrocatalytic treatment under visible light illumination. - Highlights: • α-Fe{sub 2}O{sub 3} film is prepared by liquid phase deposition process. • LPD α-Fe{sub 2}O{sub 3} film has a porous structure and absorbs visible light. • Calcination temperature shows a significant effect on the PEC performance of α-Fe{sub 2}O{sub 3} film. • α-Fe{sub 2}O{sub 3} film is efficient for photoelectrocatalytic degradation of pollutants.

  11. A Component-Minimized Single-Phase Active Power Decoupling Circuit with Reduced Current Stress to Semiconductor Switches

    DEFF Research Database (Denmark)

    Tang, Yi; Blaabjerg, Frede

    2015-01-01

    This letter proposes a novel circuit topology which can realize the power decoupling function without adding additional active switches into the circuit. The dc-link capacitor of a full bridge rectifier is split into two identical parts and the midpoint is connected to one leg through a filter in...

  12. STAT5 Activation in the Dermal Papilla Is Important for Hair Follicle Growth Phase Induction.

    Science.gov (United States)

    Legrand, Julien M D; Roy, Edwige; Ellis, Jonathan J; Francois, Mathias; Brooks, Andrew J; Khosrotehrani, Kiarash

    2016-09-01

    Hair follicles are skin appendages that undergo periods of growth (anagen), regression (catagen), and rest (telogen) regulated by their mesenchymal component, the dermal papilla (DP). On the basis of the reports of its specific expression in the DP, we investigated signal transducer and activator of transcription (STAT5) activation during hair development and cycling. STAT5 activation in the DP began in late catagen, reaching a peak in early anagen before disappearing for the rest of the cycle. This was confirmed by the expression profile of suppressor of cytokine signaling 2, a STAT5 target in the DP. This pattern of expression starts after the first postnatal hair cycle. Quantification of hair cycling using the Flash canonical Wnt signaling in vivo bioluminescence reporter found that conditional knockout of STAT5A/B in the DP targeted through Cre-recombinase under the control of the Sox18 promoter resulted in delayed anagen entry compared with control. Microarray analysis of STAT5 deletion versus control revealed key changes in tumor necrosis factor-α, Wnt, and fibroblast growth factor ligands, known for their role in inducing anagen entry. We conclude that STAT5 activation acts as a mesenchymal switch to trigger natural anagen entry in postdevelopmental hair follicle cycling. PMID:27131881

  13. Multi-wavelength Temporal Variability of the Blazar 3C 454.3 during 2014 Activity Phase

    CERN Document Server

    Kushwaha, Pankaj; Misra, Ranjeev; Singh, K P

    2016-01-01

    We present a multi-wavelength temporal analysis of the blazar 3C 454.3 during the high $\\gamma$-ray active period from May-December, 2014. Except for X-rays, the period is well sampled at near-infrared (NIR)-optical by the \\emph{SMARTS} facility and the source is detected continuously on daily timescale in the \\emph{Fermi}-LAT $\\gamma$-ray band. The source exhibits diverse levels of variability with many flaring/active states in the continuously sampled $\\gamma$-ray light curve which are also reflected in the NIR-optical light curves and the sparsely sampled X-ray light curve by the \\emph{Swift}-XRT. Multi-band correlation analysis of this continuous segment during different activity periods shows a change of state from no lags between IR and $\\gamma$-ray, optical and $\\gamma$-ray, and IR and optical to a state where $\\gamma$-ray lags the IR/optical by $\\sim$3 days. The results are consistent with the previous studies of the same during various $\\gamma$-ray flaring and active episodes of the source. This cons...

  14. A study on the characteristics of temperature inversions in active and break phases of Indian summer monsoon

    Digital Repository Service at National Institute of Oceanography (India)

    Muraleedharan, P.M.; Mohankumar, K.; Sivakumar, K.U.

    The thermal inversion characteristics during active and break cycles of two consecutive and contrasting monsoon years were studied using GPS radiosonde profiles in Goa (15 degrees 46′ N; 73 degrees 08′ E), located on the west coast of India...

  15. Pharmacokinetics and antiviral activity of PHX1766, a novel HCV protease inhibitor, using an accelerated Phase I study design

    NARCIS (Netherlands)

    D.M. Hotho (Daphne); J. Bruijne (Joep); N. O'Farrell; T. Boyea (Teresa); J. Li (Jianke); M. Bracken (Michele); X. Li (Xin); D. Campbell (David); H.-P. Guler (Hans-Peter); C.J. Weegink (Christine); J. Schinkel (Janke); R. Molenkamp (Richard); J. Van De Wetering De Rooij (Jeroen); A.A. Vliet (Andre); H.L.A. Janssen (Harry); R.J. de Knegt (Robert); H.W. Reesink (Henk)

    2012-01-01

    textabstractBackground: PHX1766 is a novel HCV NS3/4 protease inhibitor with robust potency and high selectivity in replicon studies (50% maximal effective concentration 8 nM). Two clinical trials investigated the safety, tolerability, pharmacokinetics and antiviral activity of PHX1766 in healthy vo

  16. Identification of Inhibitory Premotor Interneurons Activated at a Late Phase in a Motor Cycle during Drosophila Larval Locomotion.

    Directory of Open Access Journals (Sweden)

    Yuki Itakura

    Full Text Available Rhythmic motor patterns underlying many types of locomotion are thought to be produced by central pattern generators (CPGs. Our knowledge of how CPG networks generate motor patterns in complex nervous systems remains incomplete, despite decades of work in a variety of model organisms. Substrate borne locomotion in Drosophila larvae is driven by waves of muscular contraction that propagate through multiple body segments. We use the motor circuitry underlying crawling in larval Drosophila as a model to try to understand how segmentally coordinated rhythmic motor patterns are generated. Whereas muscles, motoneurons and sensory neurons have been well investigated in this system, far less is known about the identities and function of interneurons. Our recent study identified a class of glutamatergic premotor interneurons, PMSIs (period-positive median segmental interneurons, that regulate the speed of locomotion. Here, we report on the identification of a distinct class of glutamatergic premotor interneurons called Glutamatergic Ventro-Lateral Interneurons (GVLIs. We used calcium imaging to search for interneurons that show rhythmic activity and identified GVLIs as interneurons showing wave-like activity during peristalsis. Paired GVLIs were present in each abdominal segment A1-A7 and locally extended an axon towards a dorsal neuropile region, where they formed GRASP-positive putative synaptic contacts with motoneurons. The interneurons expressed vesicular glutamate transporter (vGluT and thus likely secrete glutamate, a neurotransmitter known to inhibit motoneurons. These anatomical results suggest that GVLIs are premotor interneurons that locally inhibit motoneurons in the same segment. Consistent with this, optogenetic activation of GVLIs with the red-shifted channelrhodopsin, CsChrimson ceased ongoing peristalsis in crawling larvae. Simultaneous calcium imaging of the activity of GVLIs and motoneurons showed that GVLIs' wave-like activity lagged

  17. Celecoxib treatment does not alter recruitment and activation of osteoclasts in the initial phase of experimental tooth movement

    Science.gov (United States)

    Carvalho-Filho, E.P.; Stabile, A.C.; Ervolino, E.; Stuani, M.B.S.; Iyomasa, M.M.; Rocha, M.J.A.

    2012-01-01

    In a previous study, we reported that the short-term treatment with celecoxib, a non-steroidal anti-inflammatory drug (NSAID) attenuates the activation of brain structures related to nociception and does not interfere with orthodontic incisor separation in rats. The conclusion was that celecoxib could possibly be prescribed for pain in orthodontic patients. However, we did not analyze the effects of this drug in periodontium. The aim of this follow-up study was to analyze effects of celecoxib treatment on recruitment and activation of osteoclasts and alveolar bone resorption after inserting an activated orthodontic appliance between the incisors in our rat model. Twenty rats (400–420 g) were pretreated through oral gavage with celecoxib (50 mg/kg) or vehicle (carboxymethyl-cellulose 0.4%). After 30 min, they received an activated (30 g) orthodontic appliance, set not to cause any palate disjunction. In sham animals, the appliance was immediately removed after introduction. All animals received ground food and, every 12 h, celecoxib or vehicle. After 48 h, they were anesthetized and transcardiacally perfused through the aorta with 4% formaldehyde. Subsequently, maxillae were removed, post-fixed and processed for histomorphometry or immunohistochemical analyses. As expected, incisor distalization induced an inflammatory response with certain histological changes, including an increase in the number of active osteoclasts at the compression side in group treated with vehicle (appliance:32.2±2.49 vs sham: 4.8±1.79, P<0.05) and celecoxib (appliance: 31.0±1.45 vs sham: 4.6±1.82, P<0.05). The treatment with celecoxib did not modify substantially the histological alterations and the number of active osteoclasts after activation of orthodontic appliance. Moreover, we did not see any difference between the groups with respect to percentage of bone resorption area. Taken together with our previous results we conclude that short-term treatment with celecoxib can indeed be

  18. CATALYST ACTIVITY MAINTENANCE FOR THE LIQUID PHASE SYNTHESIS GAS-TO-DIMETHYL ETHER PROCESS PART II: DEVELOPMENT OF ALUMINUM PHOSPHATE AS THE DEHYDRATION CATALYST FOR THE SINGLE-STEP LIQUID PHASE SYNGAS-TO-DME PROCESS

    Energy Technology Data Exchange (ETDEWEB)

    Xiang-Dong Peng

    2002-05-01

    At the heart of the single-step liquid phase syngas-to-DME process (LPDME{trademark}) is a catalyst system that can be active as well as stable. In the Alternative Fuels I program, a dual-catalyst system containing a Cu-based commercial methanol synthesis catalyst (BASF S3-86) and a commercial dehydration material ({gamma}-alumina) was demonstrated. It provided the productivity and selectivity expected from the LPDME process. However, the catalyst system deactivated too rapidly to warrant a viable commercial process [1]. The mechanistic investigation in the early part of the DOE's Alternative Fuels II program revealed that the accelerated catalyst deactivation under LPDME conditions is due to detrimental interaction between the methanol synthesis catalyst and methanol dehydration catalyst [2,3]. The interaction was attributed to migration of Cu- and/or Zn-containing species from the synthesis catalyst to the dehydration catalyst. Identification of a dehydration catalyst that did not lead to this detrimental interaction while retaining adequate dehydration activity was elusive. Twenty-nine different dehydration materials were tested, but none showed the desired performance [2]. The search came to a turning point when aluminum phosphate was tested. This amorphous material is prepared by precipitating a solution containing Al(NO{sub 3}){sub 3} and H{sub 3}PO{sub 4} with NH{sub 4}OH, followed by washing, drying and calcination. The aluminum phosphate catalyst has adequate dehydration activity and good stability. It can co-exist with the Cu-based methanol synthesis catalyst without negatively affecting the latter catalyst's stability. This report documents the details of the development of this catalyst. These include initial leads, efforts in improving activity and stability, investigation and development of the best preparation parameters and procedures, mechanistic understanding and resulting preparation guidelines, and the accomplishments of this work.

  19. Rapid microwave-assisted sol-gel preparation of Pd-substituted LnFeO3 (Ln = Y, La): phase formation and catalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Misch, Lauren M.; Birkel, Alexander; Figg, C. Adrian; Fors, Brett P.; Hawker, Craig J.; Stucky, Galen D.; Seshadri, Ram [UCSB

    2014-02-13

    We present a rapid microwave-assisted sol–gel approach to Pd-substituted LnFeO3 (Ln = Y, La) for applications in C–C coupling reactions. These materials could be prepared in household microwave ovens in less than 15 minutes of reaction time with the final materials displaying well-defined structure and morphology. Phase evolution was studied using time-dependent microwave heatings and then compared with the results obtained from thermogravimetric analyses. Materials were confirmed to be phase pure by laboratory and synchrotron X-ray diffraction. Substituted Pd is ionic as shown by the binding energy shift from X-ray photoelectron spectroscopy. The short heating periods required for phase purity allow these materials less time for sintering as compared to conventional solid state preparation methods, making relatively high surface areas achievable. These materials have been successfully used as catalyst precursor materials for C–C coupling reactions in which the active species is Pd0. Pd-substituted LnFeO3 (Ln = Y, La) provides Pd0 in solution which can be complexed by the ligand SPhos, allowing for aryl chloride coupling.

  20. Rapid microwave-assisted sol-gel preparation of Pd-substituted LnFeO3 (Ln = Y, La): phase formation and catalytic activity.

    Science.gov (United States)

    Misch, Lauren M; Birkel, Alexander; Figg, C Adrian; Fors, Brett P; Hawker, Craig J; Stucky, Galen D; Seshadri, Ram

    2014-02-01

    We present a rapid microwave-assisted sol-gel approach to Pd-substituted LnFeO3 (Ln = Y, La) for applications in C-C coupling reactions. These materials could be prepared in household microwave ovens in less than 15 minutes of reaction time with the final materials displaying well-defined structure and morphology. Phase evolution was studied using time-dependent microwave heatings and then compared with the results obtained from thermogravimetric analyses. Materials were confirmed to be phase pure by laboratory and synchrotron X-ray diffraction. Substituted Pd is ionic as shown by the binding energy shift from X-ray photoelectron spectroscopy. The short heating periods required for phase purity allow these materials less time for sintering as compared to conventional solid state preparation methods, making relatively high surface areas achievable. These materials have been successfully used as catalyst precursor materials for C-C coupling reactions in which the active species is Pd(0). Pd-substituted LnFeO3 (Ln = Y, La) provides Pd(0) in solution which can be complexed by the ligand SPhos, allowing for aryl chloride coupling. PMID:24280775

  1. Enhancement of the performance of activated carbons as municipal odor removal media by addition of a sewage-sludge-derived phase.

    Science.gov (United States)

    Sioukri, Evilambia; Bandosz, Teresa J

    2005-08-15

    Two commercial low-cost activated carbons and wood-based char were mixed with dewatered sludge and pyrolized at 950 degrees C. The sludge content on a dry basis was 23%. The obtained composite adsorbents were characterized from the point of view of surface chemistry (pH) and texture (adsorption of nitrogen at its boiling point: surface area, pore volume, pore size distributions). Then hydrogen sulfide breakthrough capacities were measured using the home-designed dynamic test. The results revealed a significant increase in the capacity of the composite adsorbents compared to the unmodified carbons. Moreover, that increase was a few times greater than the hypothetical one predicted when desulfurization performance would be the sum of the contributions of both the sludge-derived and carbon phases. This is attributed to a synergetic effect related to the dispersion of the catalysts and the presence of small pores. Mixing activated carbon provides the active centers for oxidation (coming from sludge) and the developed pore system (from the activated carbon) where products of oxidation can be stored. Moreover, in the hydrophobic pore space the volatile organic compounds present in effluent air from a municipal waste treatment plant can be adsorbed. The selectivity for H2S oxidation, as in the case of pure activated carbon, depends on the pore sizes. Smaller pores lead to a higher yield of sulfuric acid; larger pores lead to a higher yield of sulfur.

  2. Meridional motions of sunspots from 1947.9 to 1985.0. II - Latitude motions dependent on SPOT type and phase of the activity cycle

    Science.gov (United States)

    Lustig, G.; Hanslmeier, A.

    1987-01-01

    The dependence of the meridional motions of sunspots on sunspot-type and phase in the solar activity cycle for the time interval 1947.9-1985.0 is examined; this was done also with the sunspot data from the solar-observatory Kanzelhoehe. For the total time interval, investigations for each cycle were carried out only for the elder or long lasting G, H, and J sunspot groups and distinctions between similar sunspot types AB, C, D, EF, GHJ (Zuerich-classification). The meridional motions about the different activity maxima were also examined. In all investigations in the period from 1947.9 to 1985.0 a tendency to a southdrift can be observed on both hemispheres of the sun, but the mean meridional motions are between the error-bars not very significantly different from zero.

  3. Cells in G2/M phase increased in human nasopharyngeal carcinoma cell line by EBV-LMP1 through activation of NF-κB and AP-1

    Institute of Scientific and Technical Information of China (English)

    LIN DENG; JING YANG; XIAO RONG ZHAO; XI YUN DENG; LIANG ZENG; HUAN HUA GU; MIN TANG; YA CAO

    2003-01-01

    Although previous studies showed that the principal oncoprotein encoded by Epstein-Barr virus, latentmembrane protein 1(LMP1), could induce the nasopharyngeal carcinoma cells in G2/M phase increased, littleis known about the target molecules and mechanisms. The present study demonstrated that LMP1 couldinduce the accumulation of p53 protein and upregulate its transactivity in a dose dependent manner, whichresulted in the decrease of the kinase activity of cdc2/cyclin B complex and inducing arrest at G2/M phasethrough the activation of NF-κB and AP-1 signaling pathways, and the effect of NF-κB was more obviousthan that of AP-1. This study provided some significant evidence for further elucidating the molecularmechanisms that LMP1 had effects on the surveillance mechanism of cell cycle and promoting the survivalof transformed cells and tumorigenesis.

  4. Analysis on the Mechanism of Endogenous Economy Growth Under Environment Restriction --Based on Comparison between CDE and FBA%环境约束下我国经济增长的内生机理——基于CDE与FBA的数理分析与数字校正

    Institute of Scientific and Technical Information of China (English)

    梅国平; 万建香

    2012-01-01

    accumulate at bigger speed than economic growth rate such that offsets the negative effect of natural resources decreasing on economic growth rate, fundamentally achieving "win-win" performance of environment protection and economic development. And through numerical calibration we conclude : to achieve the same economic growth rate and pollution decreasing rate, compared with the First best allocation (FBA) tion tax model, the competition decentralized equilibrium and charges more contribution from the "clean" (CDE) model demands bigger dynamic cumulative poilu- type input element. Therefore, the main contribution of this paper lies in : first, the main three kinds of environmental policy are introduced and made endogenous, with which Hamilton model is established, so the necessity of endogenous environmental policy on the win-win of economy and environment is highlighted fully; secondly, the pollution production factors and technology progress, human capital and clean technology are all introduced into the model, based on endogenous economic growth framework, we analyze the growth rates of the relative variables under the stimula- tion of environmental policy, then we reveal the mechanism by which environmental policy promotes the win-win of economy and environment; Thirdly, based on the mathematical analysis and digital simulation, comparing the CDE model with FBA model, we analyze the reasons of the gap, whether there exists balance point between the two mod- els, lastly we analyze relative policy implication. To sum up, our policy recommendations are as follows : ( 1 ) Implement the "dynamic progressive" pollution tax policy, give full play to its leading role in environmental regulation. Because only the implementation of fixed pollution tax is not enough to prevent the enterprise to increase the input of resources and the pollution emission. (2) Encourage and make full use of pubhc participation mechanism. Because residents

  5. Solid‐Phase Synthesis and Biological Evaluation of N‐Dipeptido L‐Homoserine Lactones as Quorum Sensing Activators

    DEFF Research Database (Denmark)

    Hansen, Mette Reimert; Le Quement, Sebastian Thordal; Jakobsen, Tim Holm;

    2014-01-01

    Bacteria use small signaling molecules to communicate in a process termed “quorum sensing” (QS), which enables the coordination of survival strategies, such as production of virulence factors and biofilm formation. In Gram‐negative bacteria, these signaling molecules are a series of N‐acylated L......‐homoserine lactones. With the goal of identifying non‐native compounds capable of modulating bacterial QS, a virtual library of N‐dipeptido L‐homoserine lactones was screened in silico with two different crystal structures of LasR. The 30 most promising hits were synthesized on HMBA‐functionalized PEGA resin...... and released through an efficient acid‐mediated cyclative release mechanism. Subsequent screening for modulation of QS in Pseudomonas aeruginosa and E. coli identified six moderately strong activators. A follow‐up library designed from the preliminary derived structure–activity relationships was synthesized...

  6. Liquid phase epitaxy and spectroscopic investigation of optically active KYb(WO4)2 thin layers

    NARCIS (Netherlands)

    Aznar, A.; Ehrentraut, D.; Romanyuk, Y.E.; Solé, R.; Aguiló, M.; Gerner, P.; Güdel, H.U.; Pollnau, M.

    2003-01-01

    In recent years, Yb3+ has attracted much attention as an activating ion because of its small quantum defect for laser emission from 2F5/2 to 2F7/2 at ~1.03 µm, which provides high efficiency and reduced heat generation. A promising material for Yb3+ lasers is KYb(WO4)2 (KYbW) [1]. It can be grown fr

  7. Towards automated solid phase radiofluorination for dose-on-demand PET. Retention of activity by solid support

    Energy Technology Data Exchange (ETDEWEB)

    Mathiessen, Bente; Severin, Gregory; Zhuravlev, Fedor [Technical Univ. Denmark, Risoe Campus, Roskilde (Denmark). Hevesy Lab.

    2015-06-01

    On-column [{sup 18}F]fluoride trapping and radiofluorination of 2-(naphthalen-1-yl)ethyl-4-methylbenzenesulfonate (C{sub 10}H{sub 7}(CH{sub 2}){sub 2}OTs), performed on polystyrene supported phosphazene base PS-P{sub 2}{sup tBu} yielded [{sup 18}F]1-(2-fluoroethyl)naphthalene ([{sup 18}F]C{sub 10}H{sub 7}(CH{sub 2}){sub 2}F) in 50% radiochemical yield but left up to 43% of activity unreacted on the resin. This activity could be eluted with Kryptofix/K{sub 2}CO{sub 3} and then used for conventional radiofluorination of the same substrate, suggesting that the column-retained activity was present in the form of [{sup 18}F]fluoride entrapped in polymer matrix. An approach to minimize the amount of entrapped [{sup 18}F]fluoride by use of glass beads functionalized with alkylsilane-derivatized phosphazene residues was attempted but was stymied by fluorolysis/hydrolysis of the alkylsilane spacer. The results suggest that the key to high yield of on-column radiofluorination is to minimize the residual [{sup 18}F]fluoride absorption in the matrix by the judicious choice of solid support.

  8. Efficient and tuneable photoluminescent boehmite hybrid nanoplates lacking metal activator centres for single-phase white LEDs.

    Science.gov (United States)

    Bai, Xue; Caputo, Gianvito; Hao, Zhendong; Freitas, Vânia T; Zhang, Jiahua; Longo, Ricardo L; Malta, Oscar L; Ferreira, Rute A S; Pinna, Nicola

    2014-01-01

    White light-emitting diodes (WLEDs) are candidates to revolutionize the lighting industry towards energy efficient and environmental friendly lighting and displays. The current challenges in WLEDs encompass high luminous efficiency, chromatic stability, high colour-rending index and price competitiveness. Recently, the development of efficient and low-cost downconverting photoluminescent phosphors for ultraviolet/blue to white light conversion was highly investigated. Here we report a simple route to design high-efficient WLEDs by combining a commercial ultraviolet LED chip (InGaAsN, 390 nm) and boehmite (γ-AlOOH) hybrid nanoplates. Unusually high quantum yields (ηyield=38-58%) result from a synergic energy transfer between the boehmite-related states and the triplet states of the benzoate ligands bound to the surface of the nanoplates. The nanoplates with ηyield=38% are able to emit white light with Commission International de l'Eclairage coordinates, colour-rendering index and correlated colour temperature values of (0.32, 0.33), 85.5 and 6,111 K, respectively; overwhelming state-of-the-art single-phase ultraviolet-pumped WLEDs phosphors. PMID:25483290

  9. 高分子固-固相变材料的热性能%Preparation and Properties of Paraffin/Active Carbon Phase Change Materials

    Institute of Scientific and Technical Information of China (English)

    王忠; 陈立贵; 付蕾

    2012-01-01

    以活性炭颗粒(ACG)为吸附增强材料,高密度聚乙烯(HDPE)、聚乙二醇(PEG)为相变材料,采用物理共混法制备两种高分子固-固相变材料.利用差示扫描量热仪、导热系数测定仪、高温综合热分析仪对所得相变材料的热性能进行了研究.结果表明:入活性炭颗粒,可提高材料的导热系数和热稳定性.%The preparation and characterization of novel solid-solid phase change materials by blending was reported. The main materials were high density polyethylene, polyethylene glycol and active carbon granule. The composite were characterized by differential scanning calorimetry, Thermal conductivity device and thermo-gravimetric apparatus. The results indicated that the thermo-stability and the thermal conductivity of phase changed materials both increase after adding active carbon granule.

  10. The evolution of strength and crystalline phases for alkali-activated ground blast furnace slag and fly ash-based geopolymers

    Energy Technology Data Exchange (ETDEWEB)

    Jae Eun Oh; Paulo J.M. Monteiro; Ssang Sun Jun; Sejin Choi; Simon M. Clark [University of California, Berkeley, CA (United States). Department of Civil and Environmental Engineering

    2010-02-15

    The increase in strength and evolution of crystalline phases in inorganic polymer cement, made by the alkali activation of slag, Class C and Class F fly ashes, was followed using compressive strength test and synchrotron X-ray diffraction. In order to increase the crystallinity of the product the reactions were carried out at 80{sup o}C. We found that hydrotalcite formed in both the alkali-activated slag cements and the fly ash-based geopolymers. Hydroxycancrinite, one member of the ABC-6 family of zeolites, was found only in the fly ash geopolymers. Assuming that the predominantly amorphous geopolymer formed under ambient conditions relates to the crystalline phases found when the mixture is cured at high temperature, we propose that the structure of this zeolitic precursor formed in Na-based high alkaline environment can be regarded as a disordered form of the basic building unit of the ABC-6 group of zeolites which includes poly-types such as hydroxycancrinite, hydroxysodalite and chabazite-Na.

  11. Influence of size-induced oxidation state of platinum nanoparticles on selectivity and activity in catalytic methanol oxidation in the gas phase.

    Science.gov (United States)

    Wang, Hailiang; Wang, Yihai; Zhu, Zhongwei; Sapi, Andras; An, Kwangjin; Kennedy, Griffin; Michalak, William D; Somorjai, Gabor A

    2013-06-12

    Pt nanoparticles with various sizes of 1, 2, 4, and 6 nm were synthesized and studied as catalysts for gas-phase methanol oxidation reaction toward formaldehyde and carbon dioxide under ambient pressure (10 Torr of methanol, 50 Torr of oxygen, and 710 Torr of helium) at a low temperature of 60 °C. While the 2, 4, and 6 nm nanoparticles exhibited similar catalytic activity and selectivity, the 1 nm nanoparticles showed a significantly higher selectivity toward partial oxidation of methanol to formaldehyde, but a lower total turnover frequency. The observed size effect in catalysis was correlated to the size-dependent structure and oxidation state of the Pt nanoparticles. X-ray photoelectron spectroscopy and infrared vibrational spectroscopy using adsorbed CO as molecular probes revealed that the 1 nm nanoparticles were predominantly oxidized while the 2, 4, and 6 nm nanoparticles were largely metallic. Transmission electron microscopy imaging witnessed the transition from crystalline to quasicrystalline structure as the size of the Pt nanoparticles was reduced to 1 nm. The results highlighted the important impact of size-induced oxidation state of Pt nanoparticles on catalytic selectivity as well as activity in gas-phase methanol oxidation reactions. PMID:23701488

  12. The 2006-2007 Active Phase of Anomalous X-ray Pulsar 4U 0142+61: Radiative and Timing Changes, Bursts, and Burst Spectral Features

    CERN Document Server

    Gavriil, Fotis P; Kaspi, Victoria M

    2009-01-01

    After at least 6 years of quiescence, Anomalous X-ray Pulsar (AXP) 4U 0142+61 entered an active phase in 2006 March that lasted several months and included six X-ray bursts as well as many changes in the persistent X-ray emission. The bursts, the first seen from this AXP in >11 years of Rossi X-ray Timing Explorer monitoring, all occurred in the interval between 2006 April 6 and 2007 February 7. The burst durations ranged from 8-3x10^3 s. The first five burst spectra are well modeled by blackbodies, with temperatures kT ~ 2-6 keV. However, the sixth burst had a complicated spectrum that is well characterized by a blackbody plus three emission features whose amplitude varied throughout the burst. The most prominent feature was at 14.0 keV. Upon entry into the active phase the pulsar showed a significant change in pulse morphology and a likely timing glitch. The glitch had a total frequency jump of 1.9+/-0.4 x 10^-7 Hz, which recovered with a decay time of 17+/-2 days by more than the initial jump, implying a n...

  13. EFFECT OF INVOCATION (DO’A ON PAIN-COPING BEHAVIORS OF PRIMIPAROUS MUSLIM WOMEN DURING THE FIRST THREE HOURS OF THE ACTIVE PHASE OF LABOR

    Directory of Open Access Journals (Sweden)

    Desmawati

    2016-10-01

    Full Text Available Background: Pain-coping behavior of primiparous women may have adverse effects on the mother and fetus. In Tangerang, the majority of pregnant women have negative experiences of pain and pain-coping behaviors during labor. Objective: The purpose of this study was to examine the effect of the invocation (do’a on pain-coping behaviors of primiparous Muslim women during the first 3 hours of the active phase of labor. Methods: It was an experimental study with pre-posttest design. Ten primiparos women were randomly selected and assigned to the control and intervention group. Each group conssisted of 5 participants. Pain-coping behavior was measured by the Pain Behavior Observation Scale (POBS. Results: Findings revealed that pain-coping behaviors were increased for those who received the invocation (do’a with p-value < .05 than those who received the routine care. The effectiveness of do'a could be seen from the average difference of scores of pain-coping behaviors before and after intervention. The intervention group significantly had higher pain-coping behaviors than the control group during three hours of posttest, while controlling for the pretest measure, F (3.24 = 15.68, p< .001. Conclusions: The invocation (do’a program for primiparos women during labor is feasible to be conducted, and effective to increase pain-coping behaviors. Therefore, it is suggested to provide this program for primiparos women during the first 3 hours of active phase of labor.

  14. Induction of phase 2 antioxidant enzymes by broccoli sulforaphane: Perspectives in maintaining the antioxidant activity of vitamins A, C, and E

    Directory of Open Access Journals (Sweden)

    Sekhar s Boddupalli

    2012-01-01

    Full Text Available Consumption of fruits and vegetables is recognized as an important part of a healthy diet. Increased consumption of cruciferous vegetables in particular has been associated with a decreased risk of several degenerative and chronic diseases, including cardiovascular disease and certain cancers. Members of the cruciferous vegetable family, which includes broccoli, Brussels sprouts, cauliflower, and cabbage, accumulate significant concentrations of glucosinolates, which are metabolized in vivo to biologically active isothiocyanates (ITCs. The ITC sulforaphane, which is derived from glucoraphanin, has garnered particular interest due to its extraordinary ability to induce expression of several enzymes via the Keap1/Nrf2/ARE pathway. Nrf2/ARE gene products are typically characterized as Phase II detoxification enzymes and/or antioxidant (AO enzymes. Over the last decade, human clinical studies have begun to provide in vivo evidence of both Phase II and AO enzyme induction by SF. Many AO enzymes are redox cycling enzymes that maintain redox homeostasis and activity of free radical scavengers such as such as vitamins A, C and E. In this review, we present the existing evidence for induction of PII and AO enzymes by SF, the interactions of SF-induced AO enzymes and proposed maintenance of the essential vitamins A, C and E, and, finally, the current view of genotypic effects on ITC metabolism and AO enzyme induction and function.

  15. A study of the shadowing of galactic cosmic rays by the sun in a quiet phase of solar activity with the Tibet air shower array

    CERN Document Server

    Amenomori, M

    2000-01-01

    We have shown that the Sun's shadow by high energy cosmic rays moves year by year and its behavior is correlated with a time variation of the large-scale structure of the solar and interplanetary magnetic fields. The solar activity was near minimum in the period from 1996 through 1997. Using the data obtained with the Tibet air shower array, we examined the shadowing of cosmic rays by the Sun in this quiet phase of solar cycle, and found that the Sun's shadow was just in the apparent direction of the Sun, though it was observed at the position considerably away from the Sun to the south-west in the period between 1990 and 1993. It is known that the magnetic pole of equivalent solar dipole was reversed during the previous active phase, and near solar minimum the dipole was aligned with the rotating axis, preserving its N-pole on the north pole side of the Sun. This causes the solar magnetic field to shift the Sun's shadow to the east. Thus, the observed results suggest that the shift of the Sun's shadow due to...

  16. A systematic investigation of quaternary ammonium ions as asymmetric phase-transfer catalysts. Application of quantitative structure activity/selectivity relationships.

    Science.gov (United States)

    Denmark, Scott E; Gould, Nathan D; Wolf, Larry M

    2011-06-01

    Although the synthetic utility of asymmetric phase-transfer catalysis continues to expand, the number of proven catalyst types and design criteria remains limited. At the origin of this scarcity is a lack in understanding of how catalyst structural features affect the rate and enantioselectivity of phase transfer catalyzed reactions. Described in this paper is the development of quantitative structure-activity relationships (QSAR) and -selectivity relationships (QSSR) for the alkylation of a protected glycine imine with libraries of quaternary ammonium ion catalysts. Catalyst descriptors including ammonium ion accessibility, interfacial adsorption affinity, and partition coefficient were found to correlate meaningfully with catalyst activity. The physical nature of the descriptors was rationalized through differing contributions of the interfacial and extraction mechanisms to the reaction under study. The variation in the observed enantioselectivity was rationalized employing a comparative molecular field analysis (CoMFA) using both the steric and electrostatic fields of the catalysts. A qualitative analysis of the developed model reveals preferred regions for catalyst binding to afford both configurations of the alkylated product.

  17. The evolution of strength and crystalline phases for alkali-activated ground blast furnace slag and fly ash-based geopolymers

    KAUST Repository

    Oh, Jae Eun

    2010-02-01

    The increase in strength and evolution of crystalline phases in inorganic polymer cement, made by the alkali activation of slag, Class C and Class F fly ashes, was followed using compressive strength test and synchrotron X-ray diffraction. In order to increase the crystallinity of the product the reactions were carried out at 80 °C. We found that hydrotalcite formed in both the alkali-activated slag cements and the fly ash-based geopolymers. Hydroxycancrinite, one member of the ABC-6 family of zeolites, was found only in the fly ash geopolymers. Assuming that the predominantly amorphous geopolymer formed under ambient conditions relates to the crystalline phases found when the mixture is cured at high temperature, we propose that the structure of this zeolitic precursor formed in Na-based high alkaline environment can be regarded as a disordered form of the basic building unit of the ABC-6 group of zeolites which includes poly-types such as hydroxycancrinite, hydroxysodalite and chabazite-Na. © 2009 Elsevier Ltd.

  18. The histone-like protein H-NS acts as a transcriptional repressor for expression of the anaerobic and growth phase activator AppY of Escherichia coli

    DEFF Research Database (Denmark)

    Atlung, Tove; Sund, Susanne; Olesen, Kirsten;

    1996-01-01

    The transcriptional activator AppY is required for anaerobic and stationary phase induction of the cyx-appA and hya operons of Escherichia coli, and the expression of the appY gene itself is induced by these environmental conditions. The sequence of the appY gene and its promoter region is unusua......The transcriptional activator AppY is required for anaerobic and stationary phase induction of the cyx-appA and hya operons of Escherichia coli, and the expression of the appY gene itself is induced by these environmental conditions. The sequence of the appY gene and its promoter region...... is unusually AT-rich DNA. The nucleoid-associated protein H-NS has a DNA-binding specificity for intrinscally curved AT-rich DNA. Using a single-copy transcriptional appY-lacZ fusion, we have shown that appY gene expression is derepressed in hns mutants during aerobic exponential growth. In the hns mutant...

  19. Initial experience of use of an articulated external fixator in treating Legg-Calvé-Perthes disease by means of arthrodiastasis during the active phase of the disease

    Directory of Open Access Journals (Sweden)

    Carlos Augusto Malheiros Luzo

    2016-06-01

    Full Text Available ABSTRACT OBJECTIVE: To present the preliminary results from treating patients with Legg-Calvé-Perthes Disease (LCPD by means of hip arthrodiastasis using a monolateral external fixator applied to the hip and to succinctly describe the surgical technique used, in a prospective study. METHODS: Prospective study on 18 patients with LCPD who underwent surgical treatment by means of the hip arthrodiastasis technique using a monolateral external fixator. There were 13 male and five female patients of mean age 8.5 years, ranging from five to 13 years. All the patients presented unilateral hip impairment: nine on the right side and nine on the left. The results were evaluated at maturity using clinical and radiological criteria. RESULTS: All the patients evolved with improvement of joint mobility, and pain relief was achieved in 88.9% of them. Reossification of the femoral epiphysis occurred within the first three months of the treatment. The hips operated at the necrosis stage of the disease did not passed through the fragmentation stage, thus shortening the evolution of the disease. The results were 77.8% satisfactory and 22.2% unsatisfactory. CONCLUSION: Hip arthrodiastasis with a monolateral external fixator during the active phase of LCPD improved the degree of joint mobility. Use of the arthrodiastasis technique at the necrosis stage or at the fragmentation stage (active phase of the disease presented satisfactory results from treatment of LCPD.

  20. Composition, diffusion, and antifungal activity of black mustard (Brassica nigra) essential oil when applied by direct addition or vapor phase contact.

    Science.gov (United States)

    Mejía-Garibay, Beatriz; Palou, Enrique; López-Malo, Aurelio

    2015-04-01

    In this study, we characterized the essential oil (EO) of black mustard (Brassica nigra) and quantified its antimicrobial activity, when applied by direct contact into the liquid medium or by exposure in the vapor phase (in laboratory media or in a bread-type product), against the growth of Aspergillus niger, Aspergillus ochraceus, or Penicillium citrinum. Allyl-isothiocyanate (AITC) was identified as the major component of B. nigra EO with a concentration of 378.35 mg/ml. When B. nigra EO was applied by direct contact into the liquid medium, it inhibited the growth of A. ochraceus and P. citrinum when the concentration was 2 μl/ml of liquid medium (MIC), while for A. niger, a MIC of B. nigra EO was 4 μl/ml of liquid medium. Exposure of molds to B. nigra EO in vapor phase showed that 41.1 μl of B. nigra EO per liter of air delayed the growth of P. citrinum and A. niger by 10 days, while A. ochraceus growth was delayed for 20 days. Exposure to concentrations ≥ 47 μl of B. nigra EO per liter of air (MIC) inhibited the growth of tested molds by 30 days, and they were not able to recover after further incubation into an environment free of EO (fungicidal effect). Adsorbed AITC was quantified by exposing potato dextrose agar to B. nigra EO in a vapor phase, exhibiting that AITC was retained at least 5 days when testing EO at its MIC or with higher concentrations. Mustard EO MIC was also effective against the evaluated molds inhibiting their growth for 30 days in a bread-type product when exposed to EO by vapor contact, demonstrating its antifungal activity. PMID:25836415

  1. Regulation of T lymphocyte apoptotic markers is associated to cell activation during the acute phase of dengue.

    Science.gov (United States)

    Torrentes-Carvalho, Amanda; Marinho, Cintia Ferreira; de Oliveira-Pinto, Luzia Maria; de Oliveira, Débora Batista; Damasco, Paulo Vieira; Cunha, Rivaldo Venâncio; de Souza, Luiz José; de Azeredo, Elzinandes Leal; Kubelka, Claire Fernandes

    2014-05-01

    Dengue fever, a public health problem in Brazil, may present severe clinical manifestations as result of an increased vascular permeability and coagulation disorders. T cell activation is a critical event for an effective immune response against infection, including the production of cytokines. We aim to reveal mechanisms that modulate the virus-cell interaction, with an emphasis on cell death. Apoptosis is involved in lymphocyte homeostasis, contributes to the clearance of virus-infected cells but also may play a role in the pathogenesis. Phosphatidylserine exposure on CD8T lymphocytes from dengue patients support early apoptotic processes and loss of genomic integrity, observed by DNA fragmentation in T lymphocytes and indicating late apoptosis. These T cells express activation and cytotoxic phenotypes as revealed by CD29 and CD107a upregulation. Higher frequencies of CD95 were detected in T lymphocytes mainly in those with the cytotoxic profile (CD107a+) and lower levels of anti-apoptotic molecule Bcl-2, suggesting that both CD4+ and CD8+ T cell subsets are more susceptible to apoptosis during acute dengue. The analysis of apoptosis-related protein expression profile showed that not only molecules with pro- but also those with anti-apoptotic functions are overexpressed, indicating that survival mechanisms could be possibly protecting cells against apoptosis caused by viral, immune, oxidative and/or genotoxic stresses. These observations led us to propose that in dengue patients there is an association between T cell susceptibility to apoptosis and the activation state. The mechanisms for understanding the immunopathogenesis during dengue infection are discussed.

  2. Lipolytic activity of the yeast species associated with the fermentation/storage phase of ripe olive processing.

    Science.gov (United States)

    Rodríguez-Gómez, F; Arroyo-López, F N; López-López, A; Bautista-Gallego, J; Garrido-Fernández, A

    2010-08-01

    Ripe olives account for ca. 30% of the world's table olive production. Fruits intended for this type of product are preserved in an aqueous solution (acidic water or brine) for several months, where they may undergo a spontaneous fermentation. Enterobacteriaceae and lactic acid bacteria were not detected in the present survey during storage. Thus, the work focused on studying the yeast microflora associated with the ripe olive storage of Manzanilla and Hojiblanca cultivars in acidified brines. A total of 90 yeast isolates were identified by means of molecular methods using RFLP analysis of the 5.8S-ITS rDNA region and sequencing of the D1/D2 domains of the 26S rDNA gene. The two most important species identified in both cultivars were Saccharomyces cerevisiae and Pichia galeiformis, which were present throughout the storage period, while Candida boidinii was detected during the later stages of the process. The species Pichia membranifaciens was detected only in the early stages of the Hojiblanca cultivar. The lipase assays performed with both extracellular and whole cell fractions of the yeast isolates showed that neither of the S. cerevisiae and P. galeiformis species had lipase activity, while the P. membranifaciens isolates showed a weak activity. On the contrary, all C. boidinii isolates gave a strong lipase activity. Change in olive fat acidity was markedly higher in the presence of the yeast population than in sterile storage, indicating that lipases produced by these microorganisms modify the characteristics of the fat in the fruit. PMID:20510778

  3. Study of multi-layer active magnetic regenerators using magnetocaloric materials with first and second order phase transition

    DEFF Research Database (Denmark)

    Lei, Tian; Engelbrecht, Kurt; Nielsen, Kaspar Kirstein;

    2016-01-01

    magnetocaloric refrigerators (MCR) demonstrated the great potential for these materials, but a thorough study on the impact of the moderate adiabatic temperature change and strong temperature dependence of the magnetocaloric effect (MCE) is lacking. Besides, comparing active magnetic regenerators (AMR) using...... MCE are quantified and analyzed by using artificially built magnetocaloric properties. Then, based on measured magnetocaloric properties of La(Fe,Mn,Si)13H y and Gd, an investigation on how to layer typical FOPT and SOPT materials with different temperature spans is carried out. Moreover, the...

  4. Batch, Kinetic and Equilibrium Studies of Chromium (Vi From Aqueous Phase Using Activated Carbon Derived From Lantana Camara Fruit

    Directory of Open Access Journals (Sweden)

    K. Nithya

    2015-12-01

    Full Text Available Batch experiments have been conducted to determine the maximum adsorption capacity of activated carbon derived from Lantana camara fruit to remove hexavalent chromium from aqueous solution. The removal efficiency and uptake capacity of the biosorbent were determined by varying several batch level parameters. Highest removal efficiency of the biosorbent was found to be almost 99% under optimal conditions. Maximum monolayer adsorption capacity was determined to be 86 mg/g. The experimental data best fitted with Langmuir adsorption isotherm and pseudo second order model. These findings conclude that the selected biosorbent has more promising features in binding hexavalent chromium in aqueous media.

  5. Ga doped SBA-15 as an active and stable catalyst for Friedel-Crafts liquid-phase acylation

    OpenAIRE

    EL BERRICHI, Zohra; CHERIF, Leila; ORSEN O.; TESSONIER, Jean-Philippe; VANHAECKE, Estelle; LOUIS, Benoit; LEDOUX, Marc-Jacques; Pham-Huu, Cuong

    2013-01-01

    Gallium containing SBA-15 mesoporous materials with different Si/Ga ratio were synthesized using a post-treatment procedure with an aqueous solution of Ga(NO3)3. The materials were characterised by means of elemental analysis, BET, XRD, TEM and H/D isotope exchange techniques. It appears that stable Ga-species were anchored to the siliceous matrix of SBA-15, thus generating acid properties in their host material. The catalytic activity of Ga-SBA-15 materials has been evaluated in the FriedelC...

  6. Determination of the antioxidant capacity of active food packagings by in situ gas-phase hydroxyl radical generation and high-performance liquid chromatography-fluorescence detection.

    Science.gov (United States)

    Pezo, Davinson; Salafranca, Jesús; Nerín, Cristina

    2008-01-18

    An experimental laboratory-made assembly to determine for the first time the antioxidant capacity with respect to hydroxyl (OH*) radicals of several new active packagings directly in the materials has been developed. Gas-phase OH* radicals are generated by UV-light irradiation of an aqueous H(2)O(2) aerosol. After on-line reaction with up to eight parallel test samples, remaining OH* is quantitatively trapped by a salicylic acid solution, and antioxidant capacity is indirectly assessed by HPLC-fluorescence determination of the high sensitive 2,5-dihydroxybenzoic acid formed. Several natural essential oils as well as active plastic films including in their formulation such oils have been subjected to oxidation. Polymers containing clove and oregano were the most efficient ones (up to 7.2 and 4.7 times, respectively, more antioxidant than blanks), whereas rosemary, citronella and propolis showed average efficiency. On the other hand, active materials containing ferulic acid, quercetin, catechin and thymol, as well as commercial active bags with ethylene-absorption properties, showed limited or none antioxidant protection. Experimental results and full details about experimental assembly are given. PMID:18068177

  7. A model for gas phase chemistry in interstellar clouds. II - Nonequilibrium effects and effects of temperature and activation energies

    Science.gov (United States)

    Prasad, S. S.; Huntress, W. T., Jr.

    1980-01-01

    The chemical evolution of diffuse and dense interstellar clouds is examined via the time-dependent model outlined by Prasad and Huntress (1980). This paper presents specific results for CH, CO, CH4, O2, CH2O, CN, C2, C2H, HC3N, and NH3. Comparison with observations and predictions of other contemporary models show that cloud temperature plays a very important role through the inverse temperature dependence of radiative association reactions and through activation energies in neutral reactions and selected ion-molecule reactions. The observed fractional abundance of CN with respect to H2 and more accurate recent laboratory data on CN + O and CN + O2 reactions suggest that there is an unidentified, yet efficient, mechanism for conversion of O and O2 into polyatomic species. C2H and HC3N are synthesized early in the history of dense clouds. The value of the fractional abundance of C2H remains high, because as the cloud cools down the activation energy in the C2H + O reaction closes down this most important loss channel. A rapidly decreasing fractional abundance of O with time can also accomplish the same result. The value of the fractional abundance of HC3N remains high because it is an unreactive molecule and probably does not condense readily onto grains.

  8. The Pore Confinement Effect of FDU-12 Mesochannels on MoS2 Active Phases and Their Hydrodesulfurization Performance

    Directory of Open Access Journals (Sweden)

    Cong Liu

    2016-01-01

    Full Text Available FDU-12 silica with highly ordered face-centered cubic mesoporous structure is developed as support to prepare Mo/FDU-12 catalysts for hydrodesulfurization (HDS of dibenzothiophene (DBT. A series of Mo/FDU-12 catalysts are synthesized by using incipient wetness impregnation method with different MoO3 loadings (6, 8, 10, 12, and 15 wt.%. The objective of this work is to explore the pore confinement effect of FDU-12 mesochannels on the MoS2 morphology with various metal loadings. It is found that, as increasing MoO3 loadings from 6 to 15 wt.%, the MoS2 nanocrystallites transform from monolayer to multilayer and the morphology changes from straight layered to curved and then to ring-like and finally to spherical-like morphology due to the restriction of cage-like pore channels of FDU-12 support. The HDS results show that the catalytic activity increases first and then decreases with the best HDS performance at the MoO3 loading of 10 wt.%. In addition, we compared the HDS activity of Mo catalyst supported on FDU-12 with that on the commercial γ-Al2O3 and SBA-15; the result exhibits that FDU-12 is superior to the other two supports due to its large pore size and ordered three-dimensional open pore channels.

  9. The Influence of Organized Physical Activity (Including Gymnastics) on Young Adult Skeletal Traits: Is Maturity Phase Important?

    Science.gov (United States)

    Bernardoni, Brittney; Scerpella, Tamara A; Rosenbaum, Paula F; Kanaley, Jill A; Raab, Lindsay N; Li, Quefeng; Wang, Sijian; Dowthwaite, Jodi N

    2015-05-01

    We prospectively evaluated adolescent organized physical activity (PA) as a factor in adult female bone traits. Annual DXA scans accompanied semiannual records of anthropometry, maturity, and PA for 42 participants in this preliminary analysis (criteria: appropriately timed DXA scans at ~1 year premenarche [predictor] and ~5 years postmenarche [dependent variable]). Regression analysis evaluated total adolescent interscan PA and PA over 3 maturity subphases as predictors of young adult bone outcomes: 1) bone mineral content (BMC), geometry, and strength indices at nondominant distal radius and femoral neck; 2) subhead BMC; 3) lumbar spine BMC. Analyses accounted for baseline gynecological age (years pre- or postmenarche), baseline bone status, adult body size and interscan body size change. Gymnastics training was evaluated as a potentially independent predictor, but did not improve models for any outcomes (p > .07). Premenarcheal bone traits were strong predictors of most adult outcomes (semipartial r2 = .21-0.59, p ≤ .001). Adult 1/3 radius and subhead BMC were predicted by both total PA and PA 1-3 years postmenarche (p < .03). PA 3-5 years postmenarche predicted femoral narrow neck width, endosteal diameter, and buckling ratio (p < .05). Thus, participation in organized physical activity programs throughout middle and high school may reduce lifetime fracture risk in females. PMID:25386845

  10. Nickel and cobalt as active phase on supported zirconia catalysts for bio-ethanol reforming: Influence of the reaction mechanism on catalysts performance

    Energy Technology Data Exchange (ETDEWEB)

    Padilla, R.; Rodriguez, L.; Serrano, A.; Munoz, G. [Instituto de Catalisis y Petroleoquimica (CSIC), C/ Marie Curie 2, Campus Cantoblanco, 28049 Madrid (Spain); Benito, M.; Daza, L. [Instituto de Catalisis y Petroleoquimica (CSIC), C/ Marie Curie 2, Campus Cantoblanco, 28049 Madrid (Spain); Centro de Investigaciones Energeticas Medioambientales y Tecnologicas (CIEMAT), Av. Complutense 22, 28040 Madrid (Spain)

    2010-09-15

    Steam reforming of ethanol for hydrogen production was investigated on Co/ZrO{sub 2} and Ni/ZrO{sub 2} catalysts promoted with lanthana. Catalysts were prepared by impregnation method and characterized by XRD and TPR. TPD-R experiments were also carried out to determine the role of active phase on reaction mechanism. The results suggest that adsorbed ethanol is dehydrogenated to acetaldehyde producing hydrogen. Then, the adsorbed acetaldehyde may evolve by different mechanisms, depending on the nature of active phase. On one hand, in cobalt-based catalyst, acetaldehyde could be reformed directly. By acetaldehyde thermal decomposition, methyl and formaldehyde groups are obtained. By coupling of methyl groups, ethane can be obtained. At medium temperature range, WGS reaction contribution is noteworthy. On the other hand, in nickel-based catalyst, acetone was detected in a higher temperature range as the main intermediate reaction product, which indicates that acetaldehyde is transformed into acetone by decarbonylation of acetaldehyde leading to H{sub 2} and CO{sub 2} formation. In addition, acetone can also be reformed to give both H{sub 2} and CO{sub 2}. Contrary to cobalt-based catalyst, ethylene was detected at intermediate range temperature which suggests that it was formed by ethanol dehydration reaction. Ethylene polymerization could easily explain coke formation, which must be avoided. Steam reforming reaction was studied at S/C ratio of 4.84 and 700 C, to verify the activity, selectivity and stability of the catalysts. Ethanol conversion reached 100% and catalysts were very stable for almost 50 h on stream. No significant differences were detected in both catalysts. Nevertheless, TPO experiments performed on used samples demonstrate a higher carbon production on nickel based catalyst that can be correlated to ethanol dehydration contribution on it reaction pathway. (author)

  11. Continuous Hydrolysis and Liquid–Liquid Phase Separation of an Active Pharmaceutical Ingredient Intermediate Using a Miniscale Hydrophobic Membrane Separator

    DEFF Research Database (Denmark)

    Cervera Padrell, Albert Emili; Morthensen, Sofie Thage; Lewandowski, Daniel Jacob;

    2012-01-01

    capillary pressure (Laplace pressure) combined with a large number of pores per unit area offering low pressure drop. The separation device can easily be operated by means of a back-pressure regulator ensuring flow-independent separation efficiency. Simple monitoring and control strategies as well as...... scaling-up/out approaches are proposed, concluding that membrane-based L-L separation may become a standard unit operation for continuous pharmaceutical manufacturing....... a PTFE membrane with 28 cm2 of active area. A less challenging separation of water and toluene was achieved at total flow rates as high as 80 mL/min, with potential to achieve even higher flow rates. The operability and flexibility of the membrane separator and a plate coalescer were compared...

  12. Determination of Activity Coefficients of di-(2-ethylhexyl) Phosphoric Acid Dimer in Select Organic Solvents Using Vapor Phase Osmometry

    Energy Technology Data Exchange (ETDEWEB)

    Michael F. Gray; Peter Zalupski; Mikael Nilsson

    2013-08-01

    Effective models for solvent extraction require accurate characterization of the nonideality effects for each component, including the extractants. In this study, the nonideal behavior of the industrial extractant di(2-ethylhexyl) phosphoric acid has been investigated using vapor pressure osmometry (VPO). From the osmometry data, activity coefficients for the HDEHP dimer were obtained based on a formulation of the regular solution theory of Scatchard and Hildebrand, and the Margules two- and three-suffix equations. The results show similarity with a slope-analysis based relation from previous literature, although important differences are highlighted. The work points towards VPO as a useful technique for this type of study, but care must be taken with the choice of standard and method of analysis.

  13. Effect of constituent phase on mechanical properties of 9Cr–1WVTa reduced activation ferritic–martensitic steels

    International Nuclear Information System (INIS)

    Influence of the formation of ferrite and accompanying carbides in martensite matrix on the tensile and Charpy impact properties was investigated for reduced activation ferritic–martensitic (RAFM) 9Cr–1WVTa steel. As the fractions of ferrite and carbide adjacent to the ferrite grain boundary increase, both tensile and Charpy impact properties deteriorated in as-normalized condition. In particular, the tensile strength and elongation decreased simultaneously, which is believed to be led by the localized deformation in ferrite which is softer than martensite, promoting the formation and growth of voids. In addition, the formation of ferrite was also detrimental to the Charpy impact properties regarding to the absorbed energy because the precipitation of carbides around ferrite were vulnerable to the nucleation and propagation of cleavage cracks. The degradation of tensile properties can be recovered by tempering, but the DBTT temperature still increases with presence of ferrite

  14. Ecological considerations for Project Wagon Wheel and hydraulic fracturing activities. Phase II(a). Annual summary report for 1974

    International Nuclear Information System (INIS)

    Vegetation studies were conducted to obtain data on production and biomass of shrubs and mat-forming woody plants. Tables are presented to show data for various species of plants. Aquatic studies were conducted to obtain data on benthic fauna and physical water conditions. Tables are presented to show classification of organisms per square foot of river bottom, ice thickness at water sampling locations, and stream velocities along the base of each study bluff. Mammalian studies were conducted to obtain population data on deer, mice, least chipmunk, northern grasshopper, mouse, ground squirrels, and prairie dogs. Observations were also made on antelope, moose, and mule deer. Hydraulic fracturing activities included studies on physical perturbations, vegetation documentation, and small mammal documentation

  15. [Analysis of the effect of physical group activities in patients with acquired brain injury in the subacute phase].

    Science.gov (United States)

    García-Hernández, Juan José; Mediavilla-Saldaña, Lázaro; Pérez-Rodríguez, Pérez-Rodríguez; Pérez-Tejero, Javier; González-Alted, Carlos

    2013-07-16

    Introduccion. El daño cerebral adquirido (DCA) hace referencia a cualquier tipo de lesion no degenerativa que se produce en el cerebro. Las actividades fisicas grupales (AFG) se presentan como un tratamiento efectivo para la mejora de la capacidad funcional. Objetivo. Analizar la eficacia de un programa de AFG en personas con DCA en fase subaguda para su integracion fisica en la comunidad. Pacientes y metodos. Treinta y tres pacientes con DCA, con una edad de 33,18 ± 10,39 años, participaron en un programa de AFG (talleres de circuito, equilibrio simple, equilibrio dual, desplazamiento dual y actividades fisico-deportivas) de 10 semanas. Al comenzar y concluir el programa se evaluaron las variables de velocidad (prueba de velocidad de la marcha en 10 metros), resistencia (prueba de marcha de seis minutos), equilibrio dinamico (Step Test), capacidad funcional (Timed Up and Go), escala de percepcion de seguridad (Activities-specific Balance Confidence Scale) y Physical Activity and Disability Survey (PADS), el promedio por hora de la intensidad de la actividad y el numero de pasos fuera del centro de rehabilitacion (usando monitores de actividad fisica). La prueba t para muestras relacionadas se utilizo para evaluar las diferencias en las variables. Resultados. Se hallaron diferencias significativas (p general (pregunta 3 del PADS) y numero de pasos. Conclusion. Los programas de AFG mejoran las capacidades fisicas, percepcion de seguridad, realizacion de actividad en general y numero de pasos, lo que puede conllevar una mayor participacion en la comunidad.

  16. 单相有源PFC开环控制的研究%Research on Open Loop Control of Single-Phase Active Power Factor Corrector

    Institute of Scientific and Technical Information of China (English)

    江剑峰; 杨喜军; 蒋婷; 曹中圣

    2012-01-01

    By now, in the field of single-phase active power factor correctors (PFC) , there are many control methods, which can be summarized into open control and closed control with their different merits and applicable scopes. In the paper, on the basis of the analysis of a single-phase active PFC principle needless of output voltage detection, an open loop control strategy is presented and analyzed only needing detection of post-bridge sinusoidal half-wave voltage, which can bring about follower characteristics versus input voltage and output power by means of regulation of the ratio between the mean output voltage and the RMS input voltage, and can also maintain the mean output voltage. After the simulation analysis by MATLAB/SIMULINK, a single-phase active PFC open digital control circuit based on DSP TMS320F28335 is designed and built into experimental platform and tested. The gained simulation and implementation results prove the theoretical analysis.%在单相有源PFC领域,截止目前,出现了多种控制方法,可以归类于开环控制和闭环控制,各有优缺点和所适用范围.在分析一种无需输出电压检测的单相PFC控制原理的基础上,提出和分析了一种只需检测整流桥后正弦半波电压和输出阻抗的开环控制策略,适合单级有源PFC和多级交错有源PFC,通过调节输出电压平均值与输入电压有效值之比,可以获得输出电压相对输入电压或输出功率的跟随特性,也可以维持输出电压平均值不变,在利用MATLAB/Simulink仿真分析后,基于DSPTMS320F28335设计了一种单相有源PFC的开环数字控制电路,建立实验平台进行实验测试.所得的仿真与实验结果符合相关的理论分析.

  17. Field Test and Performance Verification: Integrated Active Desiccant Rooftop Hybrid System Installed in a School - Final Report: Phase 4A

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, J

    2005-12-21

    This report summarizes the results of a field verification pilot site investigation that involved the installation of a hybrid integrated active desiccant/vapor-compression rooftop heating, ventilation, and air-conditioning (HVAC) unit at an elementary school in the Atlanta Georgia area. For years, the school had experienced serious humidity and indoor air quality (IAQ) problems that had resulted in occupant complaints and microbial (mold) remediation. The outdoor air louvers of the original HVAC units had been closed in an attempt to improve humidity control within the space. The existing vapor compression variable air volume system was replaced by the integrated active desiccant rooftop (IADR) system that was described in detail in an Oak Ridge National Laboratory (ORNL) report published in 2004 (Fischer and Sand 2004). The IADR system and all space conditions have been monitored remotely for more than a year. The hybrid system was able to maintain both the space temperature and humidity as desired while delivering the outdoor air ventilation rate required by American Society of Heating, Refrigerating and Air-Conditioning Engineers Standard 62. The performance level of the IADR unit and the overall system energy efficiency was measured and found to be very high. A comprehensive IAQ investigation was completed by the Georgia Tech Research Institute before and after the system retrofit. Before-and-after data resulting from this investigation confirmed a significant improvement in IAQ, humidity control, and occupant comfort. These observations were reported by building occupants and are echoed in a letter to ORNL from the school district energy manager. The IADR system was easily retrofitted in place of the original rooftop system using a custom curb adapter. All work was completed in-house by the school's maintenance staff over one weekend. A subsequent cost analysis completed for the school district by the design engineer of record concluded that the IADR

  18. Relationship between surface acidity and activity of solid-acid catalysts in vapour phase dehydration of methanol

    Energy Technology Data Exchange (ETDEWEB)

    Mollavali, M.; Atashi, H. [Department of Chemical Engineering, Faculty of Engineering, University of Sistan and Baluchestan, P.O. Box 98164-161, Zahedan (Iran); Yaripour, F.; Mohammadi-Jam, S. [Catalyst Research Group, Petrochemical Research and Technology Company, National Petrochemical Company, 14358, Tehran (Iran)

    2009-09-15

    A series of solid-acid catalysts comprised of {gamma}-alumina and modified {gamma}-alumina with different of silica were prepared by co-precipitation method. The catalysts were characterized using XRD, TGA, NH{sub 3}-TPD and BET techniques. Dehydration of methanol to dimethyl ether (DME) on solid-acid catalysts was studied in a fixed-bed reactor at the same operating conditions (T = 300 C, P = 16 bar, WHSV = 26.07 h{sup -} {sup 1}). According to the experimental results, silica-modified catalysts have shown better performance compared to the pure {gamma}-alumina. It was found that surface areas increase with increasing silica loading. The results of NH{sub 3}-TPD analysis showed that the surface acidity of aluminosilicate catalysts increases with increase in SiO{sub 2}/Al{sub 2}O{sub 3} molar ratio. Also, it was found that the catalysts with highest portion of weak and/or moderate acid sites exhibit the best catalytic performance and stability. The sample with 3 wt.% silica loading has exhibited the best activity for methanol conversion. (author)

  19. Surface activity of branched alkylamino-compounds and their influence on phase transfer behavior in water solutions of dyes

    Science.gov (United States)

    Li, Cuiqin; Guo, Suyue; Lin, Zhiyu; Wang, Jun; Ge, Tengjie

    2016-02-01

    Two branched alkylamino-compounds (AAC, R12-0.5G, and R12-1.0G), were synthesized from dodecylamine, methyl acrylate and ethylenediamine. The surface tension measurements on branched alkylamino- compounds demonstrated that surface activity of R12-1.0G is superior to that of R12-0.5G at 25°C. It has been found that the self-assembly of R12-1.0G and lauric acid formed by electrostatic interaction and the self-assembly of the molecule might transfer water-soluble dyes from water to toluene. These AAC might be applied for treating dyes in wastewater. The mass ratio of lauric to toluene, the concentration of R12-1.0G, and hydrophilic groups of dyes affected the transfer rate of the water-soluble dyes. The transfer rates of the watersoluble dyes by R12-1.0G were higher than that of 1.0G polyacrylamide-acrylamide.

  20. Activated carbon load equalization of gas-phase toluene: effect of cycle length and fraction of time in loading

    Energy Technology Data Exchange (ETDEWEB)

    William M. Moe; Kodi L. Collins; John D. Rhodes [Louisiana State University, Baton Rouge, LA (United States). Department of Civil and Environmental Engineering

    2007-08-01

    Fluctuating pollutant concentrations pose challenges in the design and operation of air pollution control devices such as biofilters. Effective load equalization could decrease or eliminate many of these difficulties. In research described here, experiments were conducted to evaluate effects of cycle length and fraction of time contaminants are supplied on the degree of load equalization achieved by passively operated granular activated carbon (GAC) beds. Columns packed with bituminous coal based Calgon BPL 4 x 6 mesh GAC were subjected to a variety of cyclic loading conditions in which toluene was supplied at concentrations of 1000 or 250 ppmv during loading intervals, and uncontaminated air flowed through the columns during no-loading intervals. The fraction of time when toluene was supplied ranged from 1/2 to 1/6, and cycle lengths ranged from 6 to 48 h. Results demonstrate that passively operated GAC columns can temporarily accumulate contaminants during intervals of high influent concentration and desorb contaminants during intervals of no loading, resulting in appreciable load equalization without need for external regeneration by heating or other means. Greater load equalization was achieved as the fraction of time toluene was loaded decreased and as the cycle length decreased. A pore and surface diffusion model, able to predict the level of contaminant concentration attenuation in GAC columns with reasonable accuracy, was used to further explore the range of load equalization performance expected from columns of various packed bed depths. 19 refs., 6 figs., 1 tab.

  1. Aqueous phase adsorption of cephalexin by walnut shell-based activated carbon: A fixed-bed column study

    Science.gov (United States)

    Nazari, Ghadir; Abolghasemi, Hossein; Esmaieli, Mohamad; Sadeghi Pouya, Ehsan

    2016-07-01

    The walnut shell was used as a low cost adsorbent to produce activated carbon (AC) for the removal of cephalexin (CFX) from aqueous solution. A fixed-bed column adsorption was carried out using the walnut shell AC. The effect of various parameters like bed height (1.5, 2 and 2.5 cm), flow rate (4.5, 6 and 7.5 mL/min) and initial CFX concentration (50, 100 and 150 mg/L) on the breakthrough characteristics of the adsorption system was investigated at optimum pH 6.5. The highest bed capacity of 211.78 mg/g was obtained using 100 mg/L inlet drug concentration, 2 cm bed height and 4.5 mL/min flow rate. Three kinetic models, namely Adam's-Bohart, Thomas and Yoon-Nelson were applied for analysis of experimental data. The Thomas and Yoon-Nelson models were appropriate for walnut shell AC column design under various conditions. The experimental adsorption capacity values were fitted to the Bangham and intra-particle diffusion models in order to propose adsorption mechanisms. The effect of temperature on the degradation of CFX was also studied.

  2. Overview of results of the first phase of validation activities for the IFMIF High Flux Test Module

    Energy Technology Data Exchange (ETDEWEB)

    Arbeiter, Frederik, E-mail: frederik.arbeiter@kit.edu [Karlsruhe Institute of Technology, Karlsruhe (Germany); Chen Yuming; Dolensky, Bernhard; Freund, Jana; Heupel, Tobias; Klein, Christine; Scheel, Nicola; Schlindwein, Georg [Karlsruhe Institute of Technology, Karlsruhe (Germany)

    2012-08-15

    Highlights: Black-Right-Pointing-Pointer Validation of computational fluid dynamics (CFD) modeling approach for application in the IFMIF High Flux Test Module. Black-Right-Pointing-Pointer Fabrication of prototypes of the irradiation capsules of the IFMIF High Flux Test Module. - Abstract: The international fusion materials irradiation facility (IFMIF) is projected to create an experimentally validated database of material properties relevant for fusion reactor designs. The IFMIF High Flux Test Module is the dedicated experiment to irradiate alloys in the temperature range 250-550 Degree-Sign C and up to 50 displacements per atom per irradiation cycle. The High Flux Test Module is developed to maximize the specimen payload in the restricted irradiation volume, and to minimize the temperature spread within each specimen bundle. Low pressure helium mini-channel cooling is used to offer a high integration density. Due to the demanding thermo-hydraulic and mechanical conditions, the engineering design process (involving numerical neutronic, thermo-hydraulic and mechanical analyses) is supported by extensive experimental validation activities. This paper reports on the prototype manufacturing, thermo-hydraulic modeling experiments and component tests, as well as on mechanical testing. For the testing of the 1:1 prototype of the High Flux Test Module, a dedicated test facility, the Helium Loop Karlsruhe-Low Pressure (HELOKA-LP) has been taken into service.

  3. Enhanced activity and stability of Pt–La and Pt–Ce alloys for oxygen electroreduction: the elucidation of the active surface phase

    DEFF Research Database (Denmark)

    Malacrida, Paolo; Escribano, Maria Escudero; Verdaguer Casadevall, Arnau;

    2014-01-01

    corrodes in 0.1 M HClO4 electrolyte. Angle Resolved X-ray Photoelectron Spectroscopy (AR-XPS) and Low Energy Ion Scattering (LEIS) have been extensively combined with electrochemical techniques to follow the chemical and structural changes at the surface. The highly reactive lanthanide atoms are not stable......Three different Pt-lanthanide metal alloys (Pt5La, Pt5Ce and Pt3La) have been studied as oxygen reduction reaction (ORR) electrocatalysts. Sputter-cleaned polycrystalline Pt5La and Pt5Ce exhibit more than a 3-fold activity enhancement compared to polycrystalline Pt at 0.9 V, while Pt3La heavily...... in the presence of oxygen and readily oxidize. The surface oxides are completely dissolved in the electrolyte. In Pt5La and Pt5Ce the so formed Pt overlayer provides kinetic stability against the further oxidation and dissolution. At the same time, it ensures a very high stability during ORR potential cycling...

  4. Development and validation of a stability-indicating reverse phase ultra performance liquid chromatographic method for the estimation of nebivolol impurities in active pharmaceutical ingredients and pharmaceutical formulation.

    Science.gov (United States)

    Thummala, Veera Raghava Raju; Lanka, Mohana Krishna

    2015-10-01

    A sensitive, stability-indicating gradient reverse phase ultra performance liquid chromatographic method has been developed for the quantitative estimation of nebivolol impurities in active pharmaceutical ingredient (API) and pharmaceutical formulation. Efficient chromatographic separation was achieved on an Acquity BEH C18 column (100 mm x 2.1 mm, 1.7 μm) with mobile phase of a gradient mixture. The flow rate of the mobile phase was 0.18 mL/min with column temperature of 30 degrees C and detection wavelength of 281 nm. The relative response factor values of (R*)-2-( benzylamino)-1-((S*)-6-fluorochroman-2-yl) ethanol ((R x S*) NBV-), (R)-1-((R)-6-fluorochroman-2-yl)-2-((S)-2-((S)-6-fluoro-chroman-2-yl)-2-hydroxyethyl-amino) ethanol ((RRSS) NBV-3), 1-(chroman-2-yl)-2-(2-(6-fluorochroman-2-yl)-2-hydroxyethyl amino) ethanol (monodesfluoro impurity), (S)-1-((R)-6-fluorochroman-2-yl)-2-((R)-2 (S*)-6-fluoro-chroman-2-yl)-2-hydroxyethylamino) ethanol hydrochloride ((RSRS) NBV-3) and (R*)-1-((S*)-6-fluorochroman-2-yl)-2-((S*)-2-((S*)-6-fluoro-chroman-2-yl)-2-hydroxyethylamino) ethanol ((R* S* S* S*) NBV-2) were 0.65, 0.91, 0.68, 0.92 and 0.91 respectively. Nebivolol formulation sample was subjected to the stress conditions of acid, base, oxidative, hydrolytic, thermal, humidity and photolytic degradation. Nebivolol was found to degrade significantly under peroxide stress condition. The degradation products were well resolved from nebivolol and its impurities. The peak purity test results confirmed that the nebivolol peak was homogenous and pure in all stress samples and the mass balance was found to be more than 98%, thus proving the stability-indicating power of the method. The developed method was validated according to International Conference on Hormonization (ICH) guidelines with respect to specificity, linearity, limits of detection and quantification, accuracy, precision and robustness. PMID:26930962

  5. Cloud-point extraction and reversed-phase high performance liquid chromatography for analysis of phenolic compounds and their antioxidant activity in Thai local wines.

    Science.gov (United States)

    Vichapong, Jitlada; Santaladchaiyakit, Yanawath; Burakham, Rodjana; Srijaranai, Supalax

    2014-04-01

    A cloud-point extraction (CPE) was developed for the determination of 12 phenolic compounds (i.e. gallic acid, procatechuic acid, p-hydroxybenzoic acid, vanillic acid, caffeic acid, syringic acid, p-coumaric acid, ferulic acid, guaiacol, p-cresol, o-cresol and 3,5-xylenol) using reversed-phase high performance liquid chromatography (RP-HPLC) with photodiode array (PDA) detection. The optimum CPE conditions were 2.0% (w/v) Triton X-114, 3.0% (w/v) Na2SO4 and 20-min equilibrated at 45 °C. The surfactant-rich phase was then analyzed by HPLC using a Symmetry C18 column, gradient mobile phase of acetonitrile and 1% (v/v) acetic acid, and PDA detection at 280 nm. Under the optimum condition, the target phenolic compounds were separated within 25 min. CPE gave higher enrichment factor up to 15-fold compared to that of direct analysis. The proposed method showed good analytical performances with limits of detection in the range 0.01-0.1 mg L(-1) and precisions with relative standard deviation (RSD) lower than 5% for retention time and 10% for peak area. The method was successfully applied to the analysis of phenolic compounds in Thai local wine samples. Gallic acid, procatechuic acid, and vanillic acid were the highest phenolics found in the studied wines with the contents up to 172.4, 99.1, and 26.6 mg L(-1), respectively. The recovery of the spiked wine samples (0.5, 1.0, and 2.0 mg L(-1)) were obtained in the range of 90.4-110%. High total phenolic content, total flavonoids, and antioxidant activity (DPPH method) in the studied wines were also observed.

  6. Mas-related gene (Mrg) C receptors inhibit mechanical allodynia and spinal microglia activation in the early phase of neuropathic pain in rats.

    Science.gov (United States)

    Wang, Dongmei; Xue, Yaping; Chen, Yajuan; Ruan, Liqin; Hong, Yanguo

    2016-04-01

    Mas-related gene (Mrg) C receptors are exclusively expressed in the trigeminal and dorsal root ganglia (DRG). However, their functional roles are poorly understood. This study was aimed to determine the effect of MrgC receptors on pain hypersensitivity in the early phase of neuropathic pain and its underlying mechanisms. Intrathecal (i.t.) administration of the selective MrgC receptor agonist bovine adrenal medulla 8-22 (BAM8-22) at 1 or 10nmol attenuated mechanical allodynia one day after L5 spinal nerve ligation (SNL) surgery. I.t. BAM8-22 (10 nmol) inhibited SNL-induced microglia activation in the spinal dorsal horn on day 2 post-SNL. The BAM8-22 treatment also abolished SNL-induced upregulation of neuronal nitric oxide synthesis (nNOS) in the dorsal root ganglia (DRG). On the other hand, SNL, but not sham, surgery reduced the expression of MrgC receptor mRNA in the injured L5 DRG without changing thier levels in the adjacent uninjured L4 or L6 DRG on day 2 following the surgery. These results suggest that the activation of MrgC receptors can relieve pain hypersensitivity by the inhibition of nNOS increase in DRG neurons and microglia activation in the spinal dorsal horn in the early time following peripheral nerve injury. This study provides evidence that MrgC receptors could be targeted as a novel therapy for neuropathic pain with limited unwanted effects.

  7. Design and implementation of PV-based three-phase four-wire series hybrid active power filter for power quality improvement

    Indian Academy of Sciences (India)

    M Vijayakumar; S Vijayan

    2014-08-01

    This paper proposes a Photovoltaic (PV)-based three-phase four-wire Series Hybrid Active Power Filter (SHAPF), it comprises of a Series Active Power Filter (SAPF) and an LC shunt passive filter. The proposed system eliminates both the current and voltage harmonics and compensates reactive power, neutral current and voltage interruption. A SAPF demands a source of energy for compensating the voltage sag/swell. This system found a new topology for SHAPF which utilizes the PV with DC–DC boost converter as a source of DC power for the series active filter. The compensation current reference evaluation is based on the twin formulation of the vectorial theory of electrical power theorem with Fuzzy Logic Controller (FLC). The PV array/battery managed DC–DC boost converter is employed to step up the voltage to meet the DC bus voltage requirement of the three-leg Voltage Source Inverter (VSI). The foremost benefit of the proposed system is that, it will provide uninterrupted compensation for the whole day. This system utilizes the renewable energy; accordingly saves the energy and provides the uninterruptable power supply to critical/sensitive load, through the PV array/battery bank during both day time and night time. An experimental model was established and results were obtained, which indicated the capability of the proposed control scheme.

  8. In vitro effects of steroid hormones on arylalkylamine N-acetyltransferase (AA-NAT) activity in the pineal of fish, Clarias gariepinus (Burchell, 1822) during different phases of breeding cycle.

    Science.gov (United States)

    Yanthan, L; Gupta, B B P

    2007-08-01

    In vitro effects of gonadal hormones (testosterone, 17beta-estradiol estriol and estrone) and corticosteroid hormones (corticosterone and cortisol) were studied on arylalklyamine N-acetyltransferase (AA-NAT) activity in the pineal organ of the fish, C. gariepinus during quiescent, progressive, breeding and regressive phases of its annual breeding cycle. The pineals were collected under dim red light, maintained in organ culture for 7 hr and incubated with three concentrations (10(-6), 10(-5) and 10(-4) M) of hormones for 6 hr. The treatments with gonadal hormones and corticosteroid hormones inhibited pineal AA-NAT activity in a dose-dependent manner during all the phases of the breeding cycle. AA-NAT activity was comparatively more sensitive to the inhibitory effects of the gonadal hormones during the regressive phase and less sensitive during the quiescent phase. Further, the enzyme activity was more sensitive to the inhibitory effects of corticosteroid hormones (corticosterone and cortisol) during the breeding phase and less sensitive during the quiescent phase. These findings seem to suggest that gonadal hormones and corticosteroid hormones have direct inhibitory influence on AA-NAT activity and, hence melatonin synthesis in the photoreceptive pineal organ of C. gariepinus.

  9. Third millenium ideal gas and condensed phase thermochemical database for combustion (with update from active thermochemical tables).

    Energy Technology Data Exchange (ETDEWEB)

    Burcat, A.; Ruscic, B.; Chemistry; Technion - Israel Inst. of Tech.

    2005-07-29

    The thermochemical database of species involved in combustion processes is and has been available for free use for over 25 years. It was first published in print in 1984, approximately 8 years after it was first assembled, and contained 215 species at the time. This is the 7th printed edition and most likely will be the last one in print in the present format, which involves substantial manual labor. The database currently contains more than 1300 species, specifically organic molecules and radicals, but also inorganic species connected to combustion and air pollution. Since 1991 this database is freely available on the internet, at the Technion-IIT ftp server, and it is continuously expanded and corrected. The database is mirrored daily at an official mirror site, and at random at about a dozen unofficial mirror and 'finger' sites. The present edition contains numerous corrections and many recalculations of data of provisory type by the G3//B3LYP method, a high-accuracy composite ab initio calculation. About 300 species are newly calculated and are not yet published elsewhere. In anticipation of the full coupling, which is under development, the database started incorporating the available (as yet unpublished) values from Active Thermochemical Tables. The electronic version now also contains an XML file of the main database to allow transfer to other formats and ease finding specific information of interest. The database is used by scientists, educators, engineers and students at all levels, dealing primarily with combustion and air pollution, jet engines, rocket propulsion, fireworks, but also by researchers involved in upper atmosphere kinetics, astrophysics, abrasion metallurgy, etc. This introductory article contains explanations of the database and the means to use it, its sources, ways of calculation, and assessments of the accuracy of data.

  10. Relating Alpha Power and Phase to Population Firing and Hemodynamic Activity Using a Thalamo-cortical Neural Mass Model.

    Directory of Open Access Journals (Sweden)

    Robert Becker

    2015-09-01

    Full Text Available Oscillations are ubiquitous phenomena in the animal and human brain. Among them, the alpha rhythm in human EEG is one of the most prominent examples. However, its precise mechanisms of generation are still poorly understood. It was mainly this lack of knowledge that motivated a number of simultaneous electroencephalography (EEG - functional magnetic resonance imaging (fMRI studies. This approach revealed how oscillatory neuronal signatures such as the alpha rhythm are paralleled by changes of the blood oxygenation level dependent (BOLD signal. Several such studies revealed a negative correlation between the alpha rhythm and the hemodynamic BOLD signal in visual cortex and a positive correlation in the thalamus. In this study we explore the potential generative mechanisms that lead to those observations. We use a bursting capable Stefanescu-Jirsa 3D (SJ3D neural-mass model that reproduces a wide repertoire of prominent features of local neuronal-population dynamics. We construct a thalamo-cortical network of coupled SJ3D nodes considering excitatory and inhibitory directed connections. The model suggests that an inverse correlation between cortical multi-unit activity, i.e. the firing of neuronal populations, and narrow band local field potential oscillations in the alpha band underlies the empirically observed negative correlation between alpha-rhythm power and fMRI signal in visual cortex. Furthermore the model suggests that the interplay between tonic and bursting mode in thalamus and cortex is critical for this relation. This demonstrates how biophysically meaningful modelling can generate precise and testable hypotheses about the underpinnings of large-scale neuroimaging signals.

  11. Evidence of a planetary influence on solar activity: Phase coherence of the variation in sunspot area with the tidal effect of Mercury

    CERN Document Server

    Edmonds, Ian

    2015-01-01

    There have been numerous reports of quasiperiodicities in solar activity in the intermediate period range. However, no accepted explanation for the episodic occurrence of quasiperiodicities has emerged. This paper examines the possibility that the periodicities are associated with a Mercury Sun interaction of base period 88 days. To test this idea we band pass filter the 140 year long daily sunspot area data to obtain the 88 day period and 176 day sub harmonic period components of the data and compare the time variation of the components with the time variation of the orbital radius of Mercury, or more specifically with the time variation of the tidal effect of Mercury. We were able to show that, when successive episodes of the occurrence of the 88 day period component were discrete and not overlapping in time, the time variation of this component of sunspot area was either exactly in-phase or exactly in anti-phase with the time variation of tidal effect. A similar result was obtained for the 176 day period c...

  12. Chemistry, phase formation, and catalytic activity of thin palladium-containing oxide films synthesized by plasma-assisted physical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Anders, Andre

    2010-11-26

    The chemistry, microstructure, and catalytic activity of thin films incorporating palladium were studied using scanning and transmission electron microscopies, X-ray diffraction, spectrophotometry, 4-point probe and catalytic tests. The films were synthesized using pulsed filtered cathodic arc and magnetron sputter deposition, i.e. techniques far from thermodynamic equilibrium. Catalytic particles were formed by thermally cycling thin films of the Pd-Pt-O system. The evolution and phase formation in such films as a function of temperature were discussed in terms of the stability of PdO and PtO2 in air. The catalytic efficiency was found to be strongly affected by the chemical composition, with oxidized palladium definitely playing a major role in the combustion of methane. Reactive sputter deposition of thin films in the Pd-Zr-Y-O system allowed us forming microstructures ranging from nanocrystalline zirconia to palladium nanoparticles embedded in a (Zr,Y)4Pd2O matrix. The sequence of phase formation is put in relation to simple thermodynamic considerations.

  13. Powdered activated carbons as effective phases for bar adsorptive micro-extraction (BAμE) to monitor levels of triazinic herbicides in environmental water matrices.

    Science.gov (United States)

    Neng, N R; Mestre, A S; Carvalho, A P; Nogueira, J M F

    2011-02-15

    Bar adsorptive micro-extraction using three powdered activated carbons (ACs) as adsorbent phases followed by liquid desorption and high performance liquid chromatography with diode array detection (BAμE(ACs)-LD/HPLC-DAD), was developed to monitor triazinic herbicides (atrazine, simazine and terbutylazine) in environmental water matrices. ACs used present apparent surface areas around 1000 m(2) g(-1) with an important mesoporous volume and distinct surface chemistry characteristics (pH(PZC) ranging from 6.5 to 10.4). The textural and surface chemistry properties of the ACs adsorbent phases were correlated with the analytical data for a better understanding of the overall enrichment process. Assays performed on 10 mL water samples spiked at the 10.0 μg L(-1) levels under optimized experimental conditions yielded recoveries around 100% for the three herbicides under study. The analytical performance showed good precision (RSD0.9914). By using the standard addition method, the application of the present method on real water matrices, such as surface water and wastewater, allowed very good performances at the trace level. The proposed methodology proved to be a suitable sorptive extraction alternative for the analysis of priority pollutants with polar characteristics, showing to be easy to implement, reliable, sensitive and requiring a low sample volume to monitor triazinic compounds in water matrices. PMID:21238763

  14. Multi-phase Nature of a Radiation-Driven Fountain with Nuclear Starburst in a Low-mass Active Galactic Nucleus

    CERN Document Server

    Wada, Keiichi; Meijerink, Rowin

    2016-01-01

    The structures and dynamics of molecular, atomic, and ionized gases are studied around a low-luminosity active galactic nucleus (AGN) with a small ($2\\times 10^6 M_\\odot$) black hole using 3D radiation hydrodynamic simulations. We studied, for the first time, the non-equilibrium chemistry for the X-ray dominated region in the "radiation-driven fountain" (Wada 2012) with supernova feedback. A double hollow cone structure is naturally formed without postulating a thick "torus" around a central source. The cone is occupied with an inhomogeneous, diffuse ionized gas and surrounded by a geometrically thick ($h/r \\gtrsim 1$) atomic gas. Dense molecular gases are distributed near the equatorial plane, and energy feedback from supernovae enhances their scale height. Molecular hydrogen exists in a hot phase ( > 1000 K) as well as in a cold ( $10^3$ cm$^{-3}$) phase. The velocity dispersion of H$_2$ in the vertical direction is comparable to the rotational velocity, which is consistent with near infrared observations o...

  15. Analysis of α,β,γ-hexachlorocyclohexanes in water by novel activated carbon fiber-solid phase microextraction coupled with gas chromatography--mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    SUN Tong-hua; FANG Neng-hu; ZHU Nan-wen; WANG Ya-lin; JIA Jin-ping

    2004-01-01

    A fast and simple method for determination of α, β, γ-hexachlorocyclohexanes (HCHs) in water using activated carbon fiber-solid phase microextraction(ACF-SPME) were pressented. Results showed the performance of adsorption and desorption of three HCHs on ACF were excellent. A wide linear range from 10 to 100 μg/L and detection limits of the ng/L level were obtained using ACF-SPME with GC-MS in selected ion monitoring(SIM) acquisition mode. The proposed method was also successfully applied for determination of three HCHs in tap water. Compared to commercial fibers, ACF showed some advantages such as better resistance to solvents, higher thermal stability, long lifetime and lower cost. The data demonstrated that GC-MS with ACF-SPME is well suitable for the analysis of HCHs in water.

  16. Application of an Activated Carbon-Based Support for Magnetic Solid Phase Extraction Followed by Spectrophotometric Determination of Tartrazine in Commercial Beverages

    Directory of Open Access Journals (Sweden)

    José A. Rodríguez

    2015-01-01

    Full Text Available A method is presented for magnetic solid phase extraction of tartrazine from nonalcoholic beverages. The method involves the extraction and clean-up by activated carbon covered with magnetite dispersed in the sample, followed by the magnetic isolation and desorption of the analyte by basified methanol. The tartrazine eluted from the magnetic support was determined by spectrophotometry. Under optimal conditions, the linear range of the calibration curve ranges from 3 to 30 mg L−1, with a limit of detection of 1 mg L−1. The method was validated by comparing the results with those obtained by HPLC. A precision of <5.0% was obtained in all cases and no significant differences were observed (P<0.05.

  17. Moon Phases

    Science.gov (United States)

    Riddle, Bob

    2010-01-01

    When teaching Moon phases, the focus seems to be on the sequence of Moon phases and, in some grade levels, how Moon phases occur. Either focus can sometimes be a challenge, especially without the use of models and observations of the Moon. In this month's column, the author describes some of the lessons that he uses to teach the phases of the Moon…

  18. Field Demonstration of Active Desiccant Modules Designed to Integrate with Standard Unitary Rooftop Package Equipment - Final Report: Phase 3

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, J

    2004-03-15

    This report summarizes the investigation of two active desiccant module (ADM) pilot site installations initiated in 2001. Both pilot installations were retrofits at existing facilities served by conventional heating, ventilating, and air-conditioning (HVAC) systems that had encountered frequent humidity control, indoor air quality (IAQ), and other operational problems. Each installation involved combining a SEMCO, Inc., ADM (as described in Fischer and Sand 2002) with a standard packaged rooftop unit built by the Trane Company. A direct digital control (DDC) system integral to the ADM performed the dual function of controlling the ADM/rooftop combination and facilitating data collection, trending, and remote performance monitoring. The first installation involved providing preconditioned outdoor air to replace air exhausted from the large kitchen hood and bathrooms of a Hooters restaurant located in Rome, Georgia. This facility had previously added an additional rooftop unit in an attempt to achieve occupant comfort without success. The second involved conditioning the outdoor air delivered to each room of a wing of the Mountain Creek Inn at the Callaway Gardens resort. This hotel, designed in the ''motor lodge'' format with each room opening to the outdoors, is located in southwest Georgia. Controlling the space humidity always presented a serious challenge. Uncomfortable conditions and musty odors had caused many guests to request to move to other areas within the resort. This is the first field demonstration performed by Oak Ridge National Laboratory where significant energy savings, operating cost savings, and dramatically improved indoor environmental conditions can all be claimed as the results of a retrofit desiccant equipment field installation. The ADM/rooftop combination installed at the restaurant resulted in a reduction of about 34% in the electricity used by the building's air-conditioning system. This represents a reduction of

  19. Spectroscopic study on the active site of a SiO2 supported niobia catalyst used for the gas-phase Beckmann rearrangement of cyclohexanone oxime to ε-caprolactam

    NARCIS (Netherlands)

    Maronna, M M; Kruissink, E C; Parton, R F; Soulimani, F; Weckhuysen, B M; Hoelderich, W F

    2016-01-01

    NbOx/SiO2 with a very high catalytic activity for the gas-phase Beckmann rearrangement of cyclohexanone oxime to ε-caprolactam, was investigated by different spectroscopic methods in order to obtain new insights in the formation and nature of the active sites. FT-IR spectroscopy in combination with

  20. Antimicrobial activity of Marcetia DC species (Melastomataceae and analysis of its flavonoids by reverse phase-high performance liquid chromatography coupled-diode array detector

    Directory of Open Access Journals (Sweden)

    Tonny Cley Campos Leite

    2012-01-01

    Full Text Available Background: Marcetia genera currently comprises 29 species, with approximately 90% inhabiting Bahia (Brazil, and most are endemic to the highlands of the Chapada Diamantina (Bahia. Among the species, only M. taxifolia (A.St.-Hil. DC. populates Brazil (state of Roraima to Paranα and also Venezuela, Colombia, and Guyana. Objective: This work evaluated the antimicrobial activity of hexane, ethyl acetate, and methanol extracts of three species of Marcetia (Marcetia canescens Naud., M. macrophylla Wurdack, and M. taxifolia A.StHil against several microorganism. In addition, the flavonoids were analyzed in extracts by HPLC-DAD. Materials and methods: The tests were made using Gram-positive (three strains of Staphylococcus aureus and Gram-negative (two strains of Escherichia coli, a strain of Pseudomonas aeruginosa and another of Salmonella choleraesius bacteria resistant and nonresistant to antibiotics and yeasts (two strains of Candida albicans and one of C. parapsilosis by the disk diffusion method. Solid-phase extraction (SPE was performed on the above extracts to isolate flavonoids, which were subsequently analyzed by high performance liquid chromatography coupled diode array detector (HPLC-DAD. Results: Results showed that extracts inhibited the Gram-positive bacteria and yeast. The hexane extracts possessed the lowest activity, while the ethyl acetate and methanolic extracts were more active. Conclusion: Marcetia taxifolia was more effective (active against 10 microorganisms studied, and only its methanol extract inhibited Gram-negative bacteria (P. aeruginosa and S. choleraesius. SPE and HPLC-DAD analysis showed that M. canescens and M. macrophylla contain glycosylated flavonoids, while the majority of extracts from M. taxifolia were aglycone flavonoids.