WorldWideScience

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. LuxCDE-luxAB-based promoter reporter system to monitor the Yersinia enterocolitica O:3 gene expression in vivo

    Science.gov (United States)

    Bozcal, Elif; Dagdeviren, Melih; Uzel, Atac

    2017-01-01

    It is crucial to understand the in vitro and in vivo regulation of the virulence factor genes of bacterial pathogens. In this study, we describe the construction of a versatile reporter system for Yersinia enterocolitica serotype O:3 (YeO3) based on the luxCDABE operon. In strain YeO3-luxCDE we integrated the luciferase substrate biosynthetic genes, luxCDE, into the genome of the bacterium so that the substrate is constitutively produced. The luxAB genes that encode the luciferase enzyme were cloned into a suicide vector to allow cloning of any promoter-containing fragment upstream the genes. When the obtained suicide-construct is mobilized into YeO3-luxCDE bacteria, it integrates into the recipient genome via homologous recombination between the cloned promoter fragment and the genomic promoter sequence and thereby generates a single-copy and stable promoter reporter. Lipopolysaccharide (LPS) O-antigen (O-ag) and outer core hexasaccharide (OC) of YeO3 are virulence factors necessary to colonization of the intestine and establishment of infection. To monitor the activities of the OC and O-ag gene cluster promoters we constructed the reporter strains YeO3-Poc::luxAB and YeO3-Pop1::luxAB, respectively. In vitro, at 37°C both promoter activities were highest during logarithmic growth and decreased when the bacteria entered stationary growth phase. At 22°C the OC gene cluster promoter activity increased during the late logarithmic phase. Both promoters were more active in late stationary phase. To monitor the promoter activities in vivo, mice were infected intragastrically and the reporter activities monitored by the IVIS technology. The mouse experiments revealed that both LPS promoters were well expressed in vivo and could be detected by IVIS, mainly from the intestinal region of orally infected mice. PMID:28235077

  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

    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.

  6. Identification and functional analysis of a CDE/CHR element in the POLDI promoter

    Institute of Scientific and Technical Information of China (English)

    SONG NanMeng; ZHU XiaoYu; SHI Lei; AN Jing; WU YanWei; SANG JianLi

    2009-01-01

    Chinese Center for Disease Control and Prevention, Beijing 102206, China DNA polymerase delta is encoded by the POLD1 gene, the transcription of which is strictly cell cy-cle-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)lCHR(cell cycle gene homology region) element. A series of luci-ferase reporter constructs containing various POLD1 promoter mutations were used to investigate the role of the CDF_JCHR 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 integra-tive 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.

  7. Color doppler energy (CDE) : initial ten-months experience

    Energy Technology Data Exchange (ETDEWEB)

    Ro, Young Jin; Son, Hyun Ju; Lee, Suck Hong; Kim, Byung Soo [Pusan National Univ. College of Medicine, Pusan (Korea, Republic of); Han, Kook Sang; Nam, SAng Hwa; Lee, Keum Seob [Haedong Hospital, Pusan (Korea, Republic of); Shin Se Kwon [Daedong Hospital, Pusan (Korea, Republic of)

    1996-06-01

    Color Doppler imaging(CDI) has shortcomings, including random noise, aliasing, and angle dependence. To overcome these, a method using CD US, termed power doppler or Color Doppler Energy(CDE), has recently been introduced. The purpose of this study was to show the clinical usefulness of CDE. We retrospectively analyzed the CDI and CDE of 61 cases(20 renal pseudotumors, 8 musculoskeletal inflammations, 17 epididymitis or epididymo-orchitis, 3 varicoceles, 1 normal testis, 1 hepatocellualr carcinoma, 7 renal cell carcinoma, 1 renal angiomyolipoma, and 3 splenic varices). CDI and CDE scans were obtained at the same region with constant scan plane. The color gain was increased until noise first became perceptible, and scans were always obtained in such a way that the maximum amount of vascularity was shown. Thereafter, the vascularity, vascular displacement, and the vascular relationship between CDI and CDE were compared. In 17 of 20 cases of pseudotumor in the kidney, normal vascularity was identified in CDI and CDE, but was more cleary visible in CDE. In three cases, there was no visible vascularity in CDI, but normal vascularity in CDE. In eight cases of musculoskeletal inflammation and 17 cases of epididymitis with or without orchitis, the vascularity was increased due to hyperemia, which was more prominently seen in CDE than in CDI. In three varicoceles, CDE appeared to be better in demonstrating low velocity flow. In one patient who was suspected of having acute testicular torsion, CDE was helpful in excluding this suspicion. In one case of hepatocellualr carcinoma, seven cases of renal cell carcinoma, one case of renal angiomyolipoma, and three cases of splenic varices, CDE was better than CDI in showing the vascularity, vascular relationship, and vascular displacement.

  8. 75 FR 44053 - Proposed Collection; Comment Request: CDFI/CDE Project Profiles Web Form

    Science.gov (United States)

    2010-07-27

    ... description may be for a project previously reported to the CDFI Fund through the Community Investment Impact... Community Development Financial Institutions Fund Proposed Collection; Comment Request: CDFI/CDE Project... concerning the CDFI/CDE Project Profile Web Form, a voluntary information collection effort involving...

  9. CDE-1 affects chromosome segregation through uridylation of CSR-1-bound siRNAs.

    Science.gov (United States)

    van Wolfswinkel, Josien C; Claycomb, Julie M; Batista, Pedro J; Mello, Craig C; Berezikov, Eugene; Ketting, René F

    2009-10-02

    We have studied the function of a conserved germline-specific nucleotidyltransferase protein, CDE-1, in RNAi and chromosome segregation in C. elegans. CDE-1 localizes specifically to mitotic chromosomes in embryos. This localization requires the RdRP EGO-1, which physically interacts with CDE-1, and the Argonaute protein CSR-1. We found that CDE-1 is required for the uridylation of CSR-1 bound siRNAs, and that in the absence of CDE-1 these siRNAs accumulate to inappropriate levels, accompanied by defects in both meiotic and mitotic chromosome segregation. Elevated siRNA levels are associated with erroneous gene silencing, most likely through the inappropriate loading of CSR-1 siRNAs into other Argonaute proteins. We propose a model in which CDE-1 restricts specific EGO-1-generated siRNAs to the CSR-1 mediated, chromosome associated RNAi pathway, thus separating it from other endogenous RNAi pathways. The conserved nature of CDE-1 suggests that similar sorting mechanisms may operate in other animals, including mammals.

  10. 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.

  11. 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.

  12. 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

  13. 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 

  14. 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.

  15. Phases in the active liquid phase methanol synthesis catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Sawant, A.V.; Lee, S.; Kulik, C.J.

    1988-01-01

    An attempt has been made to identify the phases present in the active catalyst for liquid phase methanol synthesis. X-ray powder diffraction was used to identify the phases. Only metallic Cu was detected, while no Cu/sup +/ species was found to be present. A significant amount of ZnCO/sub 3/ was found to be present in catalysts which had been subjected to high partial pressures of CO/sub 2/. This fact has hitherto not been reported in literature. Some speculations about the effect of ZnCO/sub 3/ on the life of the catalyst are made. 21 refs., 6 figs.

  16. 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.

  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. 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...

  19. Enhancement of gene transfer activity mediated by mannosylated dendrimer/alpha-cyclodextrin conjugate (generation 3, G3).

    Science.gov (United States)

    Arima, Hidetoshi; Chihara, Yuko; Arizono, Masayo; Yamashita, Shogo; Wada, Koki; Hirayama, Fumitoshi; Uekama, Kaneto

    2006-11-01

    To enhance gene transfer activity of dendrimers, we prepared its conjugate (generation 3, G3) with alpha-cyclodextrin bearing mannose (Man-alpha-CDE conjugates) with various degrees of substitution of the mannose moiety (DSM5, 10, 13, 20) and compared their cytotoxicity and gene transfer activity, and elucidated the enhancing mechanism for the activity. Of the various carriers used here, Man-alpha-CDE conjugate (G3, DSM10) provided the highest gene transfer activity in NR8383, A549, NIH3T3 and HepG2 cells, being independent of the expression of mannose receptors. Gene transfer activity of Man-alpha-CDE conjugate (G3, DSM10) was not decreased by the addition of 10% serum in A549 cells. Cytotoxicity of the polyplex with Man-alpha-CDE conjugates (G3, DSM10) was not observed in A549 and NIH3T3 cells up to the charge ratio of 200/1 (carrier/pDNA). The gel mobility and particle size of polyplex with Man-alpha-CDE conjugate (G3, DSM10) were relevant to those with alpha-CDE conjugate (G3), but zeta-potential, DNase I stability, pDNA condensation of the former polyplex were somewhat different from those of the latter one. Cellular association of polyplex with Man-alpha-CDE conjugate (G3, DSM10) was almost comparable to that with dendrimer (G3) complex and alpha-CDE conjugate (G3). The addition of mannan and mannose attenuated gene transfer activity of Man-alpha-CDE conjugate (G3, DSM10) in A549 cells. Alexa-pDNA complex with TRITC-Man-alpha-CDE conjugate (G3, DSM10), but not the complex with TRITC-alpha-CDE conjugate (G3), was found to translocate to nucleus at 24 h after incubation in A549 cells. HVJ-E vector including mannan, but neither the vector alone nor the vector including dextran, suppressed the nuclear localization of TRITC-Man-alpha-CDE conjugate (G3, DSM10) to a striking degree after 24 h incubation in A549 cells. These results suggest that Man-alpha-CDE conjugate (G3, DSM10) has less cytotoxicity and prominent gene transfer activity through not only its serum

  20. Active limited-angle tomographic phase microscope.

    Science.gov (United States)

    Kus, Arkadiusz; Krauze, Wojciech; Kujawinska, Malgorzata

    2015-01-01

    We demonstrate an active, holographic tomography system, working with limited angle of projections, realized by optical-only, diffraction-based beam steering. The system created for this purpose is a Mach–Zehnder interferometer modified to serve as a digital holographic microscope with a high numerical aperture illumination module and a spatial light modulator (SLM). Such a solution is fast and robust. Apart from providing an elegant solution to viewing angle shifting, it also adds new capabilities of the holographic microscope system. SLM, being an active optical element, allows wavefront correction in order to improve measurement accuracy. Integrated phase data captured with different illumination scenarios within a highly limited angular range are processed by a new tomographic reconstruction algorithm based on the compressed sensing technique: total variation minimization, which is applied here to reconstruct nonpiecewise constant samples. Finally, the accuracy of full measurement and the proposed processing path is tested for a calibrated three-dimensional micro-object as well as a biological object--C2C12 myoblast cell.

  1. 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

  2. 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.

  3. 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....

  4. Active phase compensation of quantum key distribution system

    Institute of Scientific and Technical Information of China (English)

    CHEN Wei; HAN ZhengFu; MO XiaoFan; XU FangXing; WEI Guo; GUO GuangCan

    2008-01-01

    Quantum key distribution (QKD) system must be robust enough in practical communication. Besides birefringence of fiber, system performance is notably affected by phase drift. The Faraday-Michelson QKD system can auto-compensate the birefringence of fiber, but phase shift is still a serious problem in its practical operation. In this paper, the major reason of phase drift and its effect on Faraday-Michel-son QKD system is analyzed and an effective active phase compensation scheme is proposed. By this means, we demonstrate a quantum key distribution system which can stably run over 37-km fiber in practical working condition with the long-time averaged quantum bit error rate of 1.59% and the stan-dard derivation of 0.46%. This result shows that the active phase compensation scheme is suitable to be used in practical QKD systems based on double asymmetric interferometers without additional de-vices and thermal controller.

  5. Generalized Thermodynamics of Phase Equilibria in Scalar Active Matter

    OpenAIRE

    Solon, Alexandre P.; Stenhammar, Joakim; Cates, Michael E.; Kafri, Yariv; Tailleur, Julien

    2016-01-01

    Motility-induced phase separation (MIPS) arises generically in fluids of self-propelled particles when interactions lead to a kinetic slowdown at high density. Starting from a continuum description of diffusive scalar active matter, we give a general prescription for phase equilibria that amounts, at a hydrodynamics scale, to extremalizing a generalized free energy. We illustrate our approach on two well known models: self-propelled particles interacting either through a density-dependent pro...

  6. Phase dynamics of high radiance fiber laser arrays with active phase control

    Science.gov (United States)

    Bochove, Erik; Neschke, Brendan; Nair, Niketh; Delgado, Paul; Braiman, Yehuda

    2015-03-01

    The existing model of the LOCSET technique for the active phase synchronization of fiber laser arrays (T. Shay, Opt. Express, 2006) is extended to include relevant physical properties of the system, such as inherent optical path differences (OPD), line-width and group velocity dispersion (GVD), and we also include phase "jitter" of the master oscillator's output in the model, which in experiments is implemented to induce spectral broadening for suppression of nonlinear frequency conversion. Linearization of the phase error signal, which incorrectly predicts convergence to a synchronous equilibrium state, is not performed. Instead, the closed-loop control dynamics are shown to be described by differential equations of Kuramoto type when phase corrector response dynamics are negligible. Linear stability analysis indicates that there is always one and no more than one dynamically stable state. The latter is shown to be normally synchronous, except when strong "jitter" is applied. A Liapounov function is found as subject to the validity of certain symmetry conditions.

  7. Pressure and phase equilibria in interacting active brownian spheres.

    Science.gov (United States)

    Solon, Alexandre P; Stenhammar, Joakim; Wittkowski, Raphael; Kardar, Mehran; Kafri, Yariv; Cates, Michael E; Tailleur, Julien

    2015-05-15

    We derive a microscopic expression for the mechanical pressure P in a system of spherical active Brownian particles at density ρ. Our exact result relates P, defined as the force per unit area on a bounding wall, to bulk correlation functions evaluated far away from the wall. It shows that (i) P(ρ) is a state function, independent of the particle-wall interaction; (ii) interactions contribute two terms to P, one encoding the slow-down that drives motility-induced phase separation, and the other a direct contribution well known for passive systems; and (iii) P is equal in coexisting phases. We discuss the consequences of these results for the motility-induced phase separation of active Brownian particles and show that the densities at coexistence do not satisfy a Maxwell construction on P.

  8. 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.

  9. 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...

  10. Oxytocin discontinuation after the active phase of labor is established.

    Science.gov (United States)

    Vlachos, Dimitrios-Efthymios G; Pergialiotis, Vasilios; Papantoniou, Nikolaos; Trompoukis, Stamoulis; Vlachos, Georgios D

    2015-08-01

    Despite the widespread usage of oxytocin, there is still no consensus on its mode of administration. The scope of the present meta-analysis was to assess the effect of oxytocin discontinuation after the active phase of labor is established on maternal fetal and neonatal outcomes. We searched Medline, Scopus, Popline, ClinicalTrials.gov and Google Scholar databases. Eight studies were finally retrieved, which involved 1232 parturient. We observed significantly decreased rates of cesarean sections among parturient that discontinued oxytocin (OR 0.51, 95% CI 0.35, 0.74) as well as decreased rates of uterine hyperstimulation (OR 0.33, 95% CI 0.19, 0.58). Similarly, cases of non-reassuring fetal heart rates were fewer among women that did not receive oxytocin after the establishment of the active phase of labor (OR 0.63, 95% CI 0.41, 0.97). Keeping in mind the aforementioned maternal and neonatal adverse effects that seem to result from infusion of oxytocin until delivery, future practice should aim towards its discontinuation after the establishment of the active phase of labor, as it does not seem to influence the total duration of labor. Future studies should aim towards specific populations of parturient in order to clarify whether different approaches are needed.

  11. 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.

  12. The NEA Forum on Stakeholder Confidence - Phase I Lessons and Phase II Activities

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Peter [Natural Resources Canada, Ottawa (Canada). Uranium and Radioactive Waste Div.; Pescatore, Claudio [Nuclear Energy Agency, Paris (France)

    2006-09-15

    The Forum on Stakeholder Confidence (FSC) was created under a mandate from the OECD Nuclear Energy Agency (NEA) Radioactive Waste Management Committee (RWMC) to facilitate the sharing of international experience in addressing the societal dimension of radioactive waste management. It explores means of ensuring an effective dialogue with the public, and considers ways to strengthen confidence in decision-making processes. The Forum was launched in August 2000 and completed its first phase in 00 . Major findings and principles for action were published under the title of 'Learning and Adapting to Societal Requirements'. Activities of the FSC were also reported at Valdor 2003. In the second mandate of the FSC, there is continued use of a variety of tools and formats to allow dialogue among stakeholders in an atmosphere of mutual trust: national workshops and community visits, topical sessions, and desk and interview studies. In Phase II, the FSC is exploring: the link between research, development and demonstration and stakeholder confidence; cultural and organisational changes in RWM institutions; the role of media relations and outreach opportunities; tools and processes to help society prepare and manage decisions through stakeholder involvement; and increasing the value of waste management facilities to local communities. Workshops have been held in Germany and Spain. A large set of publications makes both Phase I and Phase II findings widely available.

  13. 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...

  14. 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....

  15. 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.

  16. 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 (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.

  17. 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.

  18. Magnetic observations during the recent declining phase of solar activity

    Science.gov (United States)

    Smith, E. J.

    Changes in the heliospheric magnetic field during the recent declining phase in solar activity are reviewed and compared with observations during past sunspot cycles. The study is based principally on data obtained by IMP-8 and Ulysses. The field magnitude is found to have increased during the declining phase until it reached a maximum value of 11.5nT in approximately 1991.5, approximately two years after sunspot maximum. The field of the sun's south pole became negative after a reversal in early 1990. The sector structure disappeared at Ulysses in April 1993 when the latitude of the spacecraft was -30 deg revealing a low inclination of the heliospheric current sheet. A large outburst of solar activity in March 1991 caused four Coronal Mass Ejections (CMEs) and numerious shocks at the location of Ulysses. Following a delay of more than a year, a series of recurrent high speed streams and Corotating Interaction Regions commenced in July 1992 which were observed by IMP-8, Ulysses and Voyager 2. In all these respects, the behavior of the magnetic field mimics that seen in the two earlier sunspot cycles. The comprehensive data set suggests a correlation between the absolute value of B and sunspot number. The major solar cycle variations in the radial component (and magnitude) of the field have been successfully reproduced by a recent model consisting of a tilted solar dipole, whose strength and tilt undergo characteristic changes over the sunspot cycle, and the heliospheric current sheet. The large outbursts of activity in mid-1972, mid-1982 and the first quarter of 1991 may represent a characteristic last 'gasp' of solar activity before the sun evolves to a different state. The recurrent high speed streams in 1973, 1984 and 1992 accompany the developemnt of large asymetrical polar coronal holes and the growth in intensity of the polar cap fields. After they endure for about one year, the polar coronal holes recede and the high speed streams are replaced by weaker

  19. APE: the Active Phasing Experiment to test new control system and phasing technology for a European Extremely Large Optical Telescope

    Science.gov (United States)

    Gonte, F.; Yaitskova, N.; Derie, F.; Constanza, A.; Brast, R.; Buzzoni, B.; Delabre, B.; Dierickx, P.; Dupuy, C.; Esteves, R.; Frank, C.; Guisard, S.; Karban, R.; Koenig, E.; Kolb, J.; Nylund, M.; Noethe, L.; Surdej, I.; Courteville, A.; Wilhelm, R.; Montoya, L.; Reyes, M.; Esposito, S.; Pinna, E.; Dohlen, K.; Ferrari, M.; Langlois, M.

    2005-08-01

    The future European Extremely Large Telescope will be composed of one or two giant segmented mirrors (up to 100 m of diameter) and of several large monolithic mirrors (up to 8 m in diameter). To limit the aberrations due to misalignments and defective surface quality it is necessary to have a proper active optics system. This active optics system must include a phasing system to limit the degradation of the PSF due to misphasing of the segmented mirrors. We will present the lastest design and development of the Active Phasing Experiment that will be tested in laboratory and on-sky connected to a VLT at Paranal in Chile. It includes an active segmented mirror, a static piston plate to simulate a secondary segmented mirror and of four phasing wavefront sensors to measure the piston, tip and tilt of the segments and the aberrations of the VLT. The four phasing sensors are the Diffraction Image Phase Sensing Instrument developed by Instituto de Astrofisica de Canarias, the Pyramid Phasing Sensor developed by Arcetri Astrophysical Observatory, the Shack-Hartmann Phasing Sensor developed by the European Southern Observatory and the Zernike Unit for Segment phasing developed by Laboratoire d'Astrophysique de Marseille. A reference measurement of the segmented mirror is made by an internal metrology developed by Fogale Nanotech. The control system of Active Phasing Experiment will perform the phasing of the segments, the guiding of the VLT and the active optics of the VLT. These activities are included in the Framework Programme 6 of the European Union.

  20. Large-Aperture Membrane Active Phased-Array Antennas

    Science.gov (United States)

    Karasik, Boris; McGrath, William; Leduc, Henry

    2009-01-01

    Large-aperture phased-array microwave antennas supported by membranes are being developed for use in spaceborne interferometric synthetic aperture radar systems. There may also be terrestrial uses for such antennas supported on stationary membranes, large balloons, and blimps. These antennas are expected to have areal mass densities of about 2 kg/sq m, satisfying a need for lightweight alternatives to conventional rigid phased-array antennas, which have typical areal mass densities between 8 and 15 kg/sq m. The differences in areal mass densities translate to substantial differences in total mass in contemplated applications involving aperture areas as large as 400 sq m. A membrane phased-array antenna includes patch antenna elements in a repeating pattern. All previously reported membrane antennas were passive antennas; this is the first active membrane antenna that includes transmitting/receiving (T/R) electronic circuits as integral parts. Other integral parts of the antenna include a network of radio-frequency (RF) feed lines (more specifically, a corporate feed network) and of bias and control lines, all in the form of flexible copper strip conductors on flexible polymeric membranes. Each unit cell of a prototype antenna (see Figure 1) contains a patch antenna element and a compact T/R module that is compatible with flexible membrane circuitry. There are two membrane layers separated by a 12.7-mm air gap. Each membrane layer is made from a commercially available flexible circuit material that, as supplied, comprises a 127-micron-thick polyimide dielectric layer clad on both sides with 17.5-micron-thick copper layers. The copper layers are patterned into RF, bias, and control conductors. The T/R module is located on the back side of the ground plane and is RF-coupled to the patch element via a slot. The T/R module is a hybrid multilayer module assembled and packaged independently and attached to the membrane array. At the time of reporting the information for

  1. 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.

  2. Highly active mixed-phase TiO2 photocatalysts fabricated at low temperature and the correlation between phase composition and photocatalytic activity

    Institute of Scientific and Technical Information of China (English)

    SHI Lei; WENG Duan

    2008-01-01

    The idea of varying volume ratio of water to ethanol in solvent was firstly employed to yield phase composition controllable mixed-phase titanium dioxide (TiO2) photocatalysts via a low temperature solvothermal route at 353 K. It was found that anatase contentsincrease from 0 to 100% with increase of ethanol contents in solvent. The mixed-phase TiO2 with 60% anatase content exhibited thebest photocatalytic activity in photodecomposing formaldehyde (FAD) under UV light irradiation, which increases by about 270 or400% in comparison with single futile or anatase TiO2, and is slightly better than commercial mixed-phase TiO2 (P25). The synergisticeffect in mixed-phase TiO2 including antenna effect by rutile phase and the activation effect by anatase phase was observed. Further,partially quantitive correlation between phase composition and photocatalytic activity was ascribed to maximizing the synergistic effectand an optimal value of anatase content about 60% in mixed-phase TiO2 photocatalyst was therefore suggested.

  3. Phase Diversity and Polarization Augmented Techniques for Active Imaging

    Science.gov (United States)

    2007-03-01

    APDI) reconstruction algorithm similar to that of Seldin et al. [45]. The resulting algorithm is essentially a hybrid between multi- frame blind...aberration parameters. 4.3.4 Multi-Frame Phase Diversity Reconstruction. Seldin and Paxman expanded phase-diversity image reconstruction for Poisson...given value of f . Seldin and Paxman [45] observed that the algorithm tended to converge to local max- ima that did not represent the known object. In

  4. 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.

  5. Rapidly Activated Dynamic Phase Transitions in Nonlinear Solids

    Science.gov (United States)

    1993-02-15

    I Form Approv# edAD -A263 601 AiENTA11ON PAGE- f____________18 1. AGENCY USE ONLY (Lea"e blaWk 12. REPORT DATE 13. REPORT TYPE AND OATES COVEREO Feb...phase transforming media during high energy impact. Conversion of mechanical energy to thermal ener- gy has been studied by means of an extended theory...and Phase Structures in General Media , R. Fosdick, E. Dunn & M. Slemrod eds., IMA volume series, Springer- Verlag. Song, J. and T. L. Pence (1992

  6. 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

  7. Photosynthetic Reaction Centers as Active Molecular Electronic Components. Phase I

    Science.gov (United States)

    1993-08-13

    SDS bring to 1 liter with H20, pH to 8.3 10% APS = 10% (w/v) Ammonium persulfate Assemble gel plates and spacers (how depends on apparatus). Mix up...the synthesis of polypyrrole microtubules in 12 Biological Components Corporation Phase I Final Report SBIR ARMY 92-103 commercially available

  8. Approach to In- Situ Producing Reinforcing Phase Within an Active-Transient Liquid Phase Bond Seam for Aluminum Matrix Composite

    Science.gov (United States)

    Zhang, Guifeng; Liao, Xianjin; Chen, Bo; Zhang, Linjie; Zhang, Jianxun

    2015-06-01

    To optimize the braze composition design route for aluminum matrix composite, the feasibility of in situ producing reinforcing phase within the transient liquid phase bond seam matrix, by adding active melting point increaser (MPI, e.g., Ti) together with general melting point depressant (MPD, e.g., Cu) into the interlayer, was demonstrated. For SiC p /A356 composite, by comparing the wettability, joint microstructure, joint shear strength, and fracture path for the developed Al-19Cu-1Ti, Al-19Cu, Al-33Cu-1Ti, Al-33Cu (wt pct), and commercial Cu foils as interlayer, the feasibility of in situ producing reinforcing phase within the bond seam by adding Ti was demonstrated. Especially for Al-19Cu-1Ti active braze, small and dispersed ternary aluminide of Al-Si-Ti phase was obtained within the bond seam as in situ reinforcement, leading to a favorable fracture path within SiC p /A356, not along the initial interface or within the bond seam. For the formation mechanism of the in situ reinforcing phase of MPI-containing intermetallic compound within the bond seam, a model of repeating concentration-precipitation-termination-engulfment during isothermal solidification is proposed.

  9. Vaginal cone use in passive and active phases in patients with stress urinary incontinence

    Directory of Open Access Journals (Sweden)

    Jorge Milhem Haddad

    2011-01-01

    Full Text Available OBJECTIVE: To evaluate vaginal cone therapy in two phases, passive and active, in women with stress urinary incontinence. METHODS: A prospective study was conducted at the Department of Obstetrics and Gynecology, São Paulo University, Brazil. Twenty-four women with a clinical and urodynamic diagnosis of stress urinary incontinence were treated with vaginal cones in a passive phase (without voluntary contractions of the pelvic floor and an active phase (with voluntary contractions, each of which lasted three months. Clinical complaints, a functional evaluation of the pelvic floor, a pad test, and bladder neck mobility were analyzed before and after each phase. RESULTS: Twenty-one patients completed the treatment. The reduction in absolute risk with the pad test was 0.38 (p<0.034 at the end of the passive phase and 0.67 (p<0.0001 at the end of the active phase. The reduction in absolute risk with the pelvic floor evaluation was 0.62 (p<0.0001 at the end of the passive phase and 0.77 (p<0.0001 at the end of the active phase. The reduction in absolute risk of bladder neck mobility was 0.38 (p<0.0089 at the end of the passive phase and 0.52 (p<0.0005 at the end of the active phase. Complete reversal of symptomatology was observed in 12 (57.1% patients, and satisfaction was expressed by 19 (90.4%. CONCLUSION: Using vaginal cones in the passive phase, as other researchers did, was effective. Inclusion of the active phase led to additional improvement in all of the study parameters evaluated in women with stress urinary incontinence. Randomized studies are needed, however, to confirm these results.

  10. Polymerisation of activated RNA in eutectic ice phases

    DEFF Research Database (Denmark)

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

    , metal catalyzed condensation reactions (s. micrograph, right). With a new, non-radioactive ex-perimental essay we are selectively monitoring the 5'-3' and 5'-2' elongation of 5'-fluorescence labeled RNA oligomers. At - 18.5 °C the polymerization reaction and its selectivity is expected to be much higher...... (“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...

  11. 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%.

  12. In-plane shear piezoelectric wafer active sensor phased arrays for structural health monitoring

    Science.gov (United States)

    Wang, Wentao; Zhou, Wensong; Wang, Peng; Wang, Chonghe; Li, Hui

    2016-04-01

    This paper proposes a new way for guided wave structural health monitoring using in-plane shear (d36 type) piezoelectric wafer active sensors phased arrays. Conventional piezoelectric wafer active sensors phased arrays based on inducing into specific Lamb wave modes (d31 type) has already widely used for health monitoring of the thin-wall structures. Rather than Lamb wave modes, the in-plane shear piezoelectric wafer active sensors phased arrays induces in-plane shear horizontal (SH) guided waves. The SH guided waves are distinct with the Lamb waves with simple waveform and less additional converted wave modes and the zero symmetric mode (SH0) is non-dispersive. In this paper, the advantage of the shear horizontal wave and the in-plane shear piezoelectric wafers capability to generate SH waves is first reviewed. Then finite element analysis of a 4-in-plane shear wafer active sensors phased array embedded on a rectangular aluminium plate is performed. In addition, numerical simulations with respect to creaks with different sizes as well as locations are implemented by the in-plane shear wafer active sensors phased array. For comparison purposes, the same numerical simulations using the conventional piezoelectric wafer active sensors phased arrays are also employed at the same time. Results indicate that the in-plane shear (d36 type) piezoelectric wafer active sensors phased arrays has the potential to identify damage location and assess damage severity in structural health monitoring.

  13. Mn Nanowhiskers of a Novel Hexagonal Phase Grown from Hydrogen Activated Laves Phase Alloys

    Institute of Scientific and Technical Information of China (English)

    WU Er-Dong; GUO Xiu-Mei

    2008-01-01

    With the aid of hydrogenation/dehydrogenation, nanorod whiskers of transition metal Mn can grow spontaneously from Zr,1-x Ti,x MnCr Laves phase alloys at room temperature. The finding introduces a distinguishingly different element into metal whisker family, and provides a potential technique for fabrication of one-dimensional metal nanostructures. Moreover, it is found that the segregated Mn in whiskers forms a novel hexagonal structure, which partially fulfills the long predicted allotropic form and adds more complexity to the structures of Mn.

  14. 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.

  15. 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.

  16. Influence of perturbative phase noise on active coherent polarization beam combining system.

    Science.gov (United States)

    Ma, Pengfei; Zhou, Pu; Wang, Xiaolin; Ma, Yanxing; Su, Rongtao; Liu, Zejin

    2013-12-02

    In this manuscript, the influence of perturbative phase noise on active coherent polarization beam combining (CPBC) system is studied theoretically and experimentally. By employing a photo-detector to obtain phase error signal for feedback loop, actively coherent polarization beam combining of two 20 W-level single mode polarization-maintained (PM) fiber amplifiers are demonstrated with more than 94% combining efficiency. Then the influence of perturbative phase noise on active CPBC system is illustrated by incorporating a simulated phase noise signal in one of the two amplifiers. Experimental results show that the combining efficiency of the CPBC system is susceptible to the frequency or amplitude of the perturbative phase noise. In order to ensure the combining efficiency of the unit of CPBC system higher than 90%, the competence of our active phase control module for high power operation is discussed, which suggests that it could be worked at 100s W power level. The relationship between residual phase noise of the active controller and the normalized voltage signal of the photo-detector is developed and validated experimentally. Experimental results correspond exactly with the theoretically analyzed combining efficiency. Our method offers a useful approach to estimate the influence of phase noise on CPBC system.

  17. Effects of intracerebroventricular histamine injection on circadian activity phase entrainment during rapid illumination changes.

    Science.gov (United States)

    Itowi, N; Yamatodani, A; Mochizuki, T; Wada, H

    1991-02-11

    Histamine is reported to have different effects on shifting the circadian activity phase depending on its circadian administration time (CT). The delay-sensitive period is CT 12-15, and the advance-sensitive period is CT 0-3. The activity phase of rats was entrained by a new light-dark cycle within a week in groups treated with either saline or i.c.v. histamine at CT 12-15. However, on treatment at CT 0-3 the activity phase of the group treated with histamine was entrained by the new light-dark cycle in half the period required for entrainment in the control group.

  18. 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.

  19. 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.

  20. 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

  1. The types and levels of physical activity and sedentary behaviour of Senior Phase learners in Potchefstroom

    Directory of Open Access Journals (Sweden)

    Johanna C.W. De Vos

    2016-12-01

    Conclusion: Strategies need to be implemented to raise the physical activity levels of Senior Phase learners, especially during weekdays, and to decrease sedentary behaviour. With this view in mind, recommendations are made for Physical Education teachers.

  2. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Overbey, W.K. Jr.; Carden, R.S.; Kirr, J.N.

    1987-04-01

    The recovery Efficiency Test well project addressed a number of technical issues. The primary objective was to determine the increased efficiency gas recovery of a long horizontal wellbore over that of a vertical wellbore and, more specifically, what improvements can be expected from inducing multiple hydraulic fractures from such a wellbore. BDM corporation located, planned, and drilled a long radius turn horizontal well in the Devonian shale Lower Huron section in Wayne County, West Virginia, demonstrating that state-of-the-art technology is capable of drilling such wells. BDM successfully tested drilling, coring, and logging in a horizontal well using air as the circulating medium; conducted reservoir modeling studies to protect flow rates and reserves in advance of drilling operations; observed two phase flow conditions in the wellbore not observed previously; cored a fracture zone which produced gas; observed that fractures in the core and the wellbore were not systematically spaced (varied from 5 to 68 feet in different parts of the wellbore); observed that highest gas show rates reported by the mud logger corresponded to zone with lowest fracture spacing (five feet) or high fracture frequency. Four and one-half inch casting was successfully installed in the borehole and was equipped to isolate the horizontal section into eight (8) zones for future testing and stimulation operations. 6 refs., 48 figs., 10 tabs.

  4. New controllability criteria for 3-phase 4-wire inverters applied to shunt active power filters

    OpenAIRE

    Perales Esteve, Manuel Ángel; Sánchez Segura, Juan Antonio; Torre, A. (Alberto) de la; Carrasco Solís, Juan Manuel; García Franquelo, Leopoldo; Terrón, L.

    2002-01-01

    In shunt active filter applications, the 3-phase 4-wire topology is frequently used when dealing with unbalanced loads containing zero sequence components. A new design criteria for this topology is presented, based on the well-known existing method for the 3-phase 3-wire system. Simulation and experimental results confirms the validity of this new criteria, providing an easy method for the design of the reactive elements involved in a shunt active filter.

  5. 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.

  6. Non-equilibrium Phase Transitions: Activated Random Walks at Criticality

    Science.gov (United States)

    Cabezas, M.; Rolla, L. T.; Sidoravicius, V.

    2014-06-01

    In this paper we present rigorous results on the critical behavior of the Activated Random Walk model. We conjecture that on a general class of graphs, including , and under general initial conditions, the system at the critical point does not reach an absorbing state. We prove this for the case where the sleep rate is infinite. Moreover, for the one-dimensional asymmetric system, we identify the scaling limit of the flow through the origin at criticality. The case remains largely open, with the exception of the one-dimensional totally-asymmetric case, for which it is known that there is no fixation at criticality.

  7. Sliding Mode Controller for Three-Phase Hybrid Active Power Filter with Photovoltaic Application

    OpenAIRE

    Blorfan, Ayman; Merckle, Jean; Flieller, Damien; Wira, Patrice; Sturtzer, Guy

    2012-01-01

    International audience; This paper presents a new three-phase hybrid active power filter configuration that interconnects a passive high-pass filter in parallel with an active power filter and a photovoltaic system. The proposed configuration can improves the filtering performance of the conventional active power filter, as well as simultaneously supply the power from the photovoltaic arrays to the load and utility. This paper will describe the proposed hybrid active power filter control usin...

  8. Full-field quantitative phase imaging by white-light interferometry with active phase stabilization and its application to biological samples

    Science.gov (United States)

    Li, Xinhong; Yamauchi, Toyohiko; Iwai, Hidenao; Yamashita, Yutaka; Zhang, Haijun; Hiruma, Teruo

    2006-06-01

    We report a Koehler-illumination-based full-field, actively stabilized, low-coherence phase-shifting interferometer, which is built on a white-light Michelson interferometer. By using a phase-stepping technique we can obtain full-field phase images of the sample. An actively stabilized phase-lock circuit is employed in the system to reduce phase noise. An application to human epithelial cells (HeLa cells) is achieved in our experiment. The advancement of this technique rests in its ability to take images of unstained biological samples quantitatively and on a nanometer scale.

  9. Role of proinflammatory cytokines on lipopolysaccharide-induced phase shifts in locomotor activity circadian rhythm.

    Science.gov (United States)

    Leone, M Juliana; Marpegan, Luciano; Duhart, José M; Golombek, Diego A

    2012-07-01

    We previously reported that early night peripheral bacterial lipopolysaccharide (LPS) injection produces phase delays in the circadian rhythm of locomotor activity in mice. We now assess the effects of proinflammatory cytokines on circadian physiology, including their role in LPS-induced phase shifts. First, we investigated whether differential systemic induction of classic proinflammatory cytokines could explain the time-specific behavioral effects of peripheral LPS. Induction levels for plasma interleukin (IL)-1α, IL-1β, IL-6, or tumor necrosis factor (TNF)-α did not differ between animals receiving a LPS challenge in the early day or early night. We next tested the in vivo effects of central proinflammatory cytokines on circadian physiology. We found that intracerebroventricular (i.c.v.) delivery of TNF-α or interleukin IL-1β induced phase delays on wheel-running activity rhythms. Furthermore, we analyzed if these cytokines mediate the LPS-induced phase shifts and found that i.c.v. administration of soluble TNF-α receptor (but not an IL-1β antagonistic) prior to LPS stimulation inhibited the phase delays. Our work suggests that the suprachiasmatic nucleus (SCN) responds to central proinflammatory cytokines in vivo, producing phase shifts in locomotor activity rhythms. Moreover, we show that the LPS-induced phase delays are mediated through the action of TNF-α at the central level, and that systemic induction of proinflammatory cytokines might be necessary, but not sufficient, for this behavioral outcome.

  10. Changes of multiple biotransformation phase Ⅰ and phase Ⅱ enzyme activities in human fetal adrenals during fetal development

    Institute of Scientific and Technical Information of China (English)

    Hui WANG; Jie PING; Ren-xiu PENG; Jiang YUE; Xue-yan XIA; Qi-xiong LI; Rui KONG; Jun-yan HONG

    2008-01-01

    Aim: Fetal adrenal, which synthesizes steroid hormones, is critical to fetal growth and development. Our recent research showed that some xenobiotics could inter-fere with steroidogenesis and induce intrauterine growth retardation in rats. The study on the characteristics of biotransformation enzymes in fetal adrenals still seems to be important with respect to possible significance in xenobiotic-induced fetal development toxicity. In this study, the activities of several important xenobiotic-related phase Ⅰ and phase Ⅱ enzymes in human fetal adrenals were examined and compared with those in fetal livers. Methods: The activity and mRNA expression were determined by enzymatic analysis and RT-PCR. Results: The levels of cytochrome (CYP)2A6, CYP2E1, and CYP3A7 isozymes in fetal adrenals were 82%, 92%, and 33% of those in fetal livers, respectively. There was a good positive correlation between adrenal CYP2A6 activity and gestational time. The values of α glutathione S-transferase (GST), πGST, and μGST in adrenals were 0.5, 4.4, and 8.3-fold of those in the livers, respectively, and the activity of adrenal πGST was negatively correlated with gestational time. The uridine diphosphoglucuronyl transferase activities, which were measured using p-hydroxy-biphenyl and 7-hydroxy-4-methylcoumarin as substrates, were 9% and 3%, respectively, of those in the fetal livers. Conclusion: Our investiga-tion suggested that adrenal could be an important xenobiotic-metabolizing or-gan in fetal development and may play a potential role in xenobiotic-induced fetal development toxicity.

  11. 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.

  12. Circadian rhythm of activity during the annual phases in the European quail, Coturnix coturnix.

    Science.gov (United States)

    Lumineau, S; Guyomarc'h, C

    2000-09-01

    Migratory birds, such as the European quail, present an annual cycle with the following phases: moult, fattening, migration and reproduction. This study aimed at determining how variations in the circadian rhythm of feeding during the annual cycle took endogenous rhythmic characteristics into account. The birds (n = 8) were maintained under constant dim light from the age of 1 to 9 months. Feeding activity was recorded using infra-red detectors. The birds expressed all the phases, except migration. Activity was arrhythmic when they were moulting. A circadian rhythm of feeding activity appeared during the fattening phase. In males, the circadian period lengthened and the clarity of the rhythm increased during sexual development. These results appear to confirm the effects of physiological state on the temporal organisation of activity. Variations of the circadian rhythm could influence the ability to synchronize with exogenous cycles such as the alternation of day and night.

  13. Brookite versus anatase TiO2 photocatalysts: phase transformations and photocatalytic activities.

    Science.gov (United States)

    Kandiel, Tarek A; Robben, Lars; Alkaim, Ayad; Bahnemann, Detlef

    2013-04-01

    Titanium dioxide nanoparticles consisting of pure anatase, anatase-rich, brookite-rich, and pure brookite modifications were synthesized and characterized by X-ray diffraction, field emission-scanning electron microscopy and nitrogen adsorption. The phase transformations among the three modifications of TiO2 (anatase, brookite, and rutile) and the photocatalytic activities of these nanoparticles were investigated by heat treatment over the temperature range from 400 to 800 °C and by the photooxidation of methanol, respectively. Direct transformation of anatase and brookite to rutile was observed, while in the case of the anatase-brookite mixture, anatase transforms firstly to brookite and then to rutile. The photocatalytic activity measurements indicate that brookite nanoparticles exhibit higher photocatalytic activities than anatase, and a comparable activity to that of the anatase-rich nanoparticles. The phase transformations and photocatalytic results are discussed regarding their dependence on crystallite size, surface area, and phase composition.

  14. 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.

  15. Scalar φ4 field theory for active-particle phase separation

    Science.gov (United States)

    Wittkowski, Raphael; Tiribocchi, Adriano; Stenhammar, Joakim; Allen, Rosalind J.; Marenduzzo, Davide; Cates, Michael E.

    2014-07-01

    Recent theories predict phase separation among orientationally disordered active particles whose propulsion speed decreases rapidly enough with density. Coarse-grained models of this process show time-reversal symmetry (detailed balance) to be restored for uniform states, but broken by gradient terms; hence, detailed-balance violation is strongly coupled to interfacial phenomena. To explore the subtle generic physics resulting from such coupling, we here introduce ‘Active Model B’. This is a scalar φ4 field theory (or phase-field model) that minimally violates detailed balance via a leading-order square-gradient term. We find that this additional term has modest effects on coarsening dynamics, but alters the static phase diagram by creating a jump in (thermodynamic) pressure across flat interfaces. Both results are surprising, since interfacial phenomena are always strongly implicated in coarsening dynamics but are, in detailed-balance systems, irrelevant for phase equilibria.

  16. SNC 80, a delta-opioid agonist, elicits phase advances in hamster circadian activity rhythms.

    Science.gov (United States)

    Byku, M; Gannon, R L

    2000-05-15

    Non-photic stimuli administered to hamsters during the subjective day can cause phase advances in circadian wheel running activity. It is believed that afferent projections from the intergeniculate leaflet of the thalamus to circadian pacemaker cells within the suprachiasmatic nucleus mediate the phase shifting effects of some non-photic stimuli. In hamsters, many of the intergeniculate leaflet afferents contain enkephalin, yet the role of opioids in producing non-photic phase shifts in hamsters has not been reported. In the present study, we show that SNC 80, an agonist for the delta opioid receptor subtype, will phase advance hamster wheel running activity rhythms when administered late in the subjective day. These results indicate that opioids may be involved in modulating the circadian pacemaker in hamsters.

  17. Interleaved Buck Converter with Variable Number of Active Phases and a Predictive Current Sharing Scheme

    DEFF Research Database (Denmark)

    Jakobsen, Lars Tønnes; Garcia, O.; Oliver, J. A.

    2008-01-01

    The efficiency of an interleaved Buck converter is typically low at light load conditions because of the switching losses in each of the switching stages. Improvements in the converter efficiency can be achieved by dynamically changing the number of active phases depending on the load current. Th...... and shows that the predictive current equalisation scheme can equalise the phase currents in a single PWM period....

  18. Active phase and polarization locking of a 1.4 kW fiber amplifier.

    Science.gov (United States)

    Goodno, Gregory D; McNaught, Stuart J; Rothenberg, Joshua E; McComb, Timothy S; Thielen, Peter A; Wickham, Michael G; Weber, Mark E

    2010-05-15

    A three-stage Yb-fiber amplifier emitted 1.43 kW of single-mode power when seeded with a 25 GHz linewidth master oscillator (MO). The amplified output was polarization stabilized and phase locked using active heterodyne phase control. A low-power sample of the output beam was coherently combined to a second fiber amplifier with 90% visibility. The measured combining efficiency agreed with estimated decoherence effects from fiber nonlinearity, linewidth, and phase-locking accuracy. This is the highest-power fiber laser that has been coherently locked using any method that allows brightness scaling.

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

    Directory of Open Access Journals (Sweden)

    Plavšić Milenko B.

    2003-01-01

    Full Text Available 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, which was also confirmed by the much better fit of the experimental data to the series type of phase coupling according to the Takanayagy theory.

  20. 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.

  1. PSYCHOPHYSIOLOGICAL CHARACTERISTICS OF WOMEN IN DEPENDENCE ON THE OVARIOHORMONAL CYCLE PHASE AND PROGESTERONE ACTIVITY (PART 2

    Directory of Open Access Journals (Sweden)

    K. B. Muravlyova

    2013-01-01

    Full Text Available With the aim to identify the effects of menstrual cycle phase on the alpha EEG characteristics the 78 women aged 18–27 years were studied in a within-subject design Half the subjects began investigation at their follicular phase and half at their luteal phase (LP. The alpha peak frequency, alpha band width and power inalpha-2 range are highest, but power in alpha 1 and activation are lowest in LP that is associated with the highest saliva progesterone level.

  2. A novel three vector sum active phase shifter design for w-band automotive radar applications

    OpenAIRE

    2014-01-01

    This article presents a novel active W-band phase shifter implemented using IHP SiGe Heterojunction Bipolar Transistor (HBT) 0.25-mu m SG25H1 technology with three vector (0 degrees-120 degrees-240 degrees) sum technique. The integrated chip consists of a 3-way Wilkinson power divider/combiner with 0 degrees-120 degrees-240 degrees phase shifting lines and three low-noise amplifiers (LNA) working at 77 GHz, which comprises a total of 1.5 x 1.1 mm(2) die area. The phase shifting is based on th...

  3. Revisiting the question: Does high-latitude solar activity lead low-latitude solar activity in time phase?

    Energy Technology Data Exchange (ETDEWEB)

    Kong, D. F.; Qu, Z. N. [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China); Guo, Q. L., E-mail: kdf@ynao.ac.cn [College of Mathematics Physics and Information Engineering, Jiaxing University, Jiaxing 314001 (China)

    2014-05-01

    Cross-correlation analysis and wavelet transform methods are used to investigate whether high-latitude solar activity leads low-latitude solar activity in time phase or not, using the data of the Carte Synoptique solar filaments archive from 1919 March to 1989 December. From the cross-correlation analysis, high-latitude solar filaments have a time lead of 12 Carrington solar rotations with respect to low-latitude ones. Both the cross-wavelet transform and wavelet coherence indicate that high-latitude solar filaments lead low-latitude ones in time phase. Furthermore, low-latitude solar activity is better correlated with high-latitude solar activity of the previous cycle than with that of the following cycle, which is statistically significant. Thus, the present study confirms that high-latitude solar activity in the polar regions is indeed better correlated with the low-latitude solar activity of the following cycle than with that of the previous cycle, namely, leading in time phase.

  4. Preparation and Properties of Paraffin/TiO2/Active-carbon Composite Phase Change Materials

    Directory of Open Access Journals (Sweden)

    HAO Yong-gan

    2016-11-01

    Full Text Available A novel composite phase change materials (PCMs of paraffin/TiO2/active-carbon was prepared by a microemulsion method, where paraffin acted as a PCM and titanium dioxide (TiO2 as matrix material, and a small amount of active carbon was added to improve the thermal conductivity. The compositions, morphology and thermal properties of the paraffin/TiO2/active-carbon composite PCMs were characterized by XRD, SEM, TGA and DSC respectively. The shape stability during phase change process of this composite was also tested. The results show that paraffin is well encapsulated by TiO2 matrix, and thus exhibiting excellent shape-stabilized phase change feature. Besides, this composite PCM also presents superhydrophobic property. Therefore, these multifunctional features will endow PCMs with important application potential in energy efficient buildings.

  5. Testicular activity during different phases of reproductive cycle in the adrenalectomized lizard, Mabuya carinata (SCHN.).

    Science.gov (United States)

    Yajurvedi, H N; Chandramohan, K

    1993-03-01

    The effects of bilateral adrenalectomy on the spermatogenetic and steroidogenic activity of the testis in different phases of the reproductive cycle of Mabuya carinata have been investigated. Adrenalectomy results in a significant decrease in the mean number of spermatogonia and primary spermatocytes, the diameters of the testis and tubule, and the activity levels of delta 5-3 beta-hydroxysteroid dehydrogenase and glucose-6-phosphate dehydrogenase in recrudescent, breeding, regressing, and quiescent phases of the reproductive cycle when compared with those of controls. Further, secondary spermatocytes, spermatids, and spermatozoa were absent in the adrenalectomized lizards in all the phases of the cycle. The results indicate the involvement of the adrenals in the recrudescence and maintenance of testicular activity in M. carinata.

  6. CP-violating Phases in Active-Sterile Solar Neutrino Oscillations

    CERN Document Server

    Long, H W; Giunti, C

    2013-01-01

    Effects of CP-violating phases in active-sterile solar neutrino oscillations are discussed in a general scheme of 3+N_{s} mixing, without any constraint on the mixing between the three active and the N_{s} sterile neutrinos, assuming only a realistic hierarchy of neutrino mass-squared differences. A generalized Parke formula describing the neutrino oscillation probabilities inside the Sun is calculated. The validity of the analytical calculation and the probability variation due to the unknown CP-violating phases are illustrated with a numerical calculation of the evolution equation in the case of 3+1 neutrino mixing.

  7. Modeling the Thermodynamics of Mixed Organic-Inorganic Aerosols to Predict Water Activities and Phase Equilibria

    Science.gov (United States)

    Zuend, A.; Marcolli, C.; Luo, B.; Peter, T.

    2008-12-01

    Tropospheric aerosol particles contain mixtures of inorganic salts, acids, water, and a large variety of organic compounds. Interactions between these substances in liquid mixtures lead to discrepancies from ideal thermodynamic behavior. While the thermodynamics of aqueous inorganic systems at atmospheric temperatures are well established, little is known about the physicochemistry of mixed organic-inorganic particles. Salting-out and salting-in effects result from organic-inorganic interactions and are used to improve industrial separation processes. In the atmosphere, they may influence the aerosol phases. Liquid-liquid phase separations into a mainly polar (aqueous) and a less polar organic phase may considerably influence the gas/particle partitioning of semi-volatile substances compared to a single phase estimation. Moreover, the phases present in the aerosol define the reaction medium for heterogeneous and multiphase chemistry occurring in aerosol particles. A correct description of these phases is needed when gas- or cloud-phase reaction schemes are adapted to aerosols. Non-ideal thermodynamic behavior in mixtures is usually described by an expression for the excess Gibbs energy. We present the group-contribution model AIOMFAC (Aerosol Inorganic-Organic Mixtures Functional groups Activity Coefficients), which explicitly accounts for molecular interactions between solution constituents, both organic and inorganic, to calculate activities, chemical potentials and the total Gibbs energy of mixed systems. This model allows to compute vapor-liquid (VLE), liquid-liquid (LLE) and solid-liquid (SLE) equilibria within one framework. Focusing on atmospheric applications we considered eight different cations, five anions and a wide range of alcohols/polyols as organic compounds. With AIOMFAC, the activities of the components within an aqueous electrolyte solution are very well represented up to high ionic strength. We show that the semiempirical middle

  8. Fostering Students' Creativity through Van Hiele's 5 Phase-Based Tangram Activities

    Science.gov (United States)

    Siew, Nyet Moi; Chong, Chin Lu

    2014-01-01

    The aim of this study was to determine whether Van Hiele's 5 phase-based tangrams activities could help to foster creativity among Grade Three primary school students. Students' creativity was investigated in terms of Torrance's Figural Test of creative thinking: Fluency, Originality, Elaboration, Abstractness of title, and Resistance to a…

  9. 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

  10. Highly integrated application specific MMICs for active phased array radar applications

    NARCIS (Netherlands)

    Bogaart, F.L.M. van den

    1999-01-01

    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

  11. Impact of active phase chemical composition and dispersity on catalytic behavior in PROX reaction

    Science.gov (United States)

    Cherkezova-Zheleva, Z.; Paneva, D.; Todorova, S.; Kolev, H.; Shopska, M.; Yordanova, I.; Mitov, I.

    2014-04-01

    Iron and iron-platinum catalysts supported on activated carbon have been successfully synthesized by wet impregnation method and low-temperature treatment in inert atmosphere. The content of the supported phases corresponds to 10 wt % Fe and 0.5 wt % Pt. Four catalytic samples were synthesized: Sample A—activated carbon impregnated with Fe nitrate; Sample B—activated carbon impregnated with Pt salt; Sample C—activated carbon impregnated consequently with Fe and Pt salts; Sample D—activated carbon impregnated simultaneously with Fe and Pt salts. The as-prepared materials were characterized by Mössbauer spectroscopy, X-ray diffraction, infrared and X-ray photoelectron spectroscopy. The spectra show that the activated carbon support and the preparation procedure give rise to the synthesis of isolated metal Pt ions and ultradispersed Fe and Pt oxide species. Probably the presence of different functional groups of activated carbon gives rise to registered very high dispersion of loaded species on support. The catalytic tests were carried out in PROX reaction. A lower activity of bimetallic Pt-Fe samples was explained with the increase in surface oxygen species as a result of predomination of iron oxide on the support leading to the increase in selectivity to the H2 oxidation. Partial agglomeration of supported iron oxide phase was registered after catalytic tests.

  12. Neural network controlled three-phase four-wire shunt active power filter

    Energy Technology Data Exchange (ETDEWEB)

    Elmitwally, A.; Abdelkader, S. [Mansura University (Egypt); El-Kateb, M. [Bath University (United Kingdom). Dept. of Electronic and Electrical Engineering

    2000-03-01

    A three-phase four-wire shunt active power filter for harmonic mitigation and reactive power compensation in power systems supplying nonlinear loads is presented. Three adaptive linear neurons are used to tackle the desired three-phase filter current templates. Another feedforward three layer neural network is adopted to control the output filter compensating currents online. This is accomplished by producing the appropriate switching patterns of the converter's legs IGBTs. Adequate tracking of the filter current references is obtained by this method. The active filter inject the current required to compensate for the harmonic and reactive components of the line currents. Simulation results of the proposed active filter indicate a remarkable improvement in the source current waveforms. This is reflected in the enhancement of the unified power quality index defined. Also, the filter has exhibited quite a high dynamic response for step variations in the load current assuring its potential for real-time applications. (author)

  13. Phase transformation of iron in hydroxyapatite in the activation of n-octane

    Energy Technology Data Exchange (ETDEWEB)

    Padayachee, D.; Dasireddy, V. D. B. C., E-mail: dasireddy@gmail.com; Bharuth-Ram, K.; Singh, S.; Friedrich, H. B. [University of KwaZulu-Natal, School of Chemistry and Physics (South Africa)

    2015-04-15

    The phase change of iron modified hydroxyapatite catalysts used in the activation of n-octane has been investigated using Mössbauer spectroscopy and powder X-ray diffraction. These catalysts were prepared using a wet impregnation and a co-precipitation technique. Both the catalysts showed the presence of an iron(III) phase. Differences were observed in the reduction behavior of the catalysts, suggesting that their reduction pathway is sensitive to the method of synthesis. This study focused on characterizing the differences in the phasic composition of the catalysts in an attempt to further understand their catalytic performance.

  14. Parametric Study to Characterize Low Activity Waste Tank Heat Removal Alternatives for Phase 1 Specification Development

    Energy Technology Data Exchange (ETDEWEB)

    GRENARD, C.E.

    2000-09-11

    Alternative for removing heat from Phase 1, low-activity waste feed double-shell tanks using the ventilation systems have been analyzed for Phase 1 waste feed delivery. The analysis was a parametric study using a model that predicted the waste temperatures for a range of primary and annulus ventilation system flow rates. The analysis was performed to determine the ventilation flow required to prevent the waste temperature from exceeding the Limiting Conditions for Operation limits during normal operation and the Safety Limits during off-normal events.

  15. 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.

  16. Kinetic attractor phase diagrams of active nematic suspensions: the dilute regime.

    Science.gov (United States)

    Forest, M Gregory; Wang, Qi; Zhou, Ruhai

    2015-08-28

    Large-scale simulations by the authors of the kinetic-hydrodynamic equations for active polar nematics revealed a variety of spatio-temporal attractors, including steady and unsteady, banded (1d) and cellular (2d) spatial patterns. These particle scale activation-induced attractors arise at dilute nanorod volume fractions where the passive equilibrium phase is isotropic, whereas all previous model simulations have focused on the semi-dilute, nematic equilibrium regime and mostly on low-moment orientation tensor and polarity vector models. Here we extend our previous results to complete attractor phase diagrams for active nematics, with and without an explicit polar potential, to map out novel spatial and dynamic transitions, and to identify some new attractors, over the parameter space of dilute nanorod volume fraction and nanorod activation strength. The particle-scale activation parameter corresponds experimentally to a tunable force dipole strength (so-called pushers with propulsion from the rod tail) generated by active rod macromolecules, e.g., catalysis with the solvent phase, ATP-induced propulsion, or light-activated propulsion. The simulations allow 2d spatial variations in all flow and orientational variables and full spherical orientational degrees of freedom; the attractors correspond to numerical integration of a coupled system of 125 nonlinear PDEs in 2d plus time. The phase diagrams with and without the polar interaction potential are remarkably similar, implying that polar interactions among the rodlike particles are not essential to long-range spatial and temporal correlations in flow, polarity, and nematic order. As a general rule, above a threshold, low volume fractions induce 1d banded patterns, whereas higher yet still dilute volume fractions yield 2d patterns. Again as a general rule, varying activation strength at fixed volume fraction induces novel dynamic transitions. First, stationary patterns saturate the instability of the isotropic

  17. 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.

    are the common features associated with the active phase. Monsoon depressions are quite frequent in this phase. On the other hand, during the break phase, the monsoon trough is shifted close to Himalayan foot-hills. The LLJ attains weak and lies around 25o N...

  18. 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.

  19. Antibacterial activity of TiO2 nanotubes: Influence of crystal phase, morphology and Ag deposition

    Science.gov (United States)

    Li, Huirong; Cui, Qiang; Feng, Bo; Wang, Jianxin; Lu, Xiong; Weng, Jie

    2013-11-01

    TiO2 nanotubes on Ti substrate were fabricated by electrochemical anodization. Ag nanoparticles were deposited on the TiO2 nanotubes by a silver mirror reaction. Antibacterial activity of the nanotubes with different structural features was evaluated by a culture test with Escherichia coli bacteria. The anatase nanotubes showed the highest antibacterial activity among three crystal phases including anatase, rutile and amorphous titania. The diameters of the nanotubes affected the antibacterial activity. The two nanotubes with 200 nm and 50 nm diameters had higher antibacterial rate than those with other diameters. The antibacterial activity of the nanotubes was independent on their lengths. Ag-deposited nanotubes exhibited excellent antibacterial activity and its antibacterial rate was up to approximately 100%. TiO2 nanotubes and Ag-deposited nanotubes on titanium should be potential for antibacterial applications in clinics and industry, especially regarding with their reusability.

  20. Inductance and Active Phase Vector Based Torque Control for Switched Reluctance Motor Drives.

    Science.gov (United States)

    Kalpathi, Ramani Raman

    The Switched Reluctance Motor (SRM) drive technology has developed significantly over the last few years. The simplicity in both motor design and power converter requirement along with the availability of high frequency, high power semiconductor switches have made SRMs compete with conventional adjustable speed drive technologies. The subject of winding current control in switched reluctance machines has always been associated with the shaft position information. The use of inductance for direct commutation control is the central subject of this dissertation. In contrast to the conventional methods based on position commutation, new methods of control based on inductance commutation are presented. The object of a commutation algorithm is to switch the currents in the phase coils, in order to provide continuous energy conversion with maximum torque output for a given unit of input current. Since torque production in a SRM is based on the concept of variable reluctance, it makes more sense to observe the instantaneous phase inductance or reluctance instead of estimating the rotor position. The inductance sensors observe the machine parameters and provide sufficient information on the electrical characteristics of the coils. This control strategy avoids the inductance to position transformation blocks conventionally used in SRM control systems. In a typical SRM, the phase coils have a nonlinear behavior of inductance due to effects of current saturation. Also the parameters of one phase coil differ from those of the other due to manufacturing tolerances or due to bearing wear. In such cases, the algorithms written during the stage of manufacturing may not be valid after parameter changes. Optimizing torque production in the event of phase asymmetry and saturation is developed in this research. Indirect sensors connected to the active phase coil of the SRM are based on sensing the flux level in the active coil. New commutation algorithms based on flux sensing concepts

  1. Final synthesis of Sarnet (Phase 1) corium activities; Synthese finale des activites corium du reseau Sarnet (Phase 1)

    Energy Technology Data Exchange (ETDEWEB)

    Journeau, Ch. [CEA Cadarache, 13 - Saint Paul lez Durance (France); Steinbruck, M. [Forschungszentrum Juelich GmbH (Germany); Repetto, G.; Duriez, Ch.; Koundy, V. [Institut de Radioprotection et de Surete Nucleaire (IRSN), 92 - Clamart (France); Ma, W.M. [Kungliga Tekniska Hoegskolan (KTH), Stockholm (Sweden); Burger, M. [Institut fur Kernenergetik und Energiesysteme, Stuttgart (IKE) (Germany); Spindler, B. [CEA Grenoble, 38 (France)

    2009-07-01

    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)

  2. Predictability during active break phases of Indian summer monsoon in an ensemble prediction system using climate forecast system

    Science.gov (United States)

    Abhilash, S.; Sahai, A. K.; Pattnaik, S.; De, S.

    2013-08-01

    This study examines the phase dependant temporal and spatial error evolution and prediction of active break spells of Indian summer monsoon rainfall in an ensemble prediction system (EPS) on a pentad time scale using climate forecast system (CFS). The EPS system shows systematic wet bias (overestimation) over west coast over the Arabian Sea and Myanmar coast and dry bias (underestimation) over Indian land mass even at pentad 1 lead and these biases consistently increase up to 4 pentad lead and saturate thereafter. Irrespective of the phases of the monsoon, the lower bound of predictability is 2 pentads, while upper bound of predictability for initial conditions starting from active phase saturates at 3 pentads and for break and transition phases predictability error saturates at a later stage at about 5 pentad. Initial conditions started from transition phase shows higher potential predictability followed by break phase and then active phase.

  3. 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 ...

  4. Ionization structure of hot components in symbiotic binaries during active phases

    CERN Document Server

    Carikova, Zuzana

    2012-01-01

    During active phases of symbiotic binaries, an optically thick medium in the form of a flared disk develops around their hot stars. During quiescent phases, this structure is not evident. We propose the formation of a flared neutral disk-like structure around the rotating white dwarf (WD) in symbiotic binaries. We applied the wind compression model and calculated the ionization boundaries in the compressed wind from the WD using the equation of photoionization equilibrium. During active phases, the compression of the enhanced wind from the rotating WD can form a neutral disk-like zone at the equatorial plane, while the remainder of the sphere above/below the disk is ionized. Calculated hydrogen column density throughout the neutral zone and the emission measure of the ionized fraction of the wind are consistent with those derived from observations. During quiescent phases, the neutral disk-like structure cannot be created because of insufficient mass loss rate. Formation of the neutral disk-like zone at the e...

  5. Enhanced photocatalytic activity in electrospun bismuth vanadate nanofibers with phase junction.

    Science.gov (United States)

    Cheng, Jing; Feng, Jing; Pan, Wei

    2015-05-13

    BiVO4 nanofibers were successfully prepared by electrospinning and precisely controlled heat treatment. The obtained BiVO4 nanofibers showed an enhanced photocatalytic activity in the degradation of rhodamine-B under visible light irradiation. The as-prepared nanofibers were characterized by means of numerous techniques. The enhanced photocatalyst activity is attributed to the formation of a phase junction of tetragonal sheelite (s-t) and monoclinic sheelite (s-m) phases in the electrospun BiVO4 nanofibers. We have also investigated the band structure of BiVO4 using first principle calculation. The main photon transition mechanism of the photocatalyst should be from the O 2p to V 3d state of s-m/t BiVO4 nanofibers.

  6. Small-World Connections to Induce Firing Activity and Phase Synchronization in Neural Networks

    Institute of Scientific and Technical Information of China (English)

    QIN Ying-Hua; LUO Xiao-Shu

    2009-01-01

    We investigate how the firing activity and the subsequent phase synchronization of neural networks with small-world topological connections depend on the probability p of adding-links. Network elements are described by two-dimensional map neurons (2DMNs) in a quiescent original state. Neurons burst for a given coupling strength when the topological randomness p increases, which is absent in a regular-lattice neural network. The bursting activity becomes frequent and synchronization of neurons emerges as topological randomness further increases.The maximal firing frequency and phase synchronization appear at a particular value of p. However, if the randomness p further increases, the firing frequency decreases and synchronization is apparently destroyed.

  7. 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.

  8. Physiologically activated phase transition systems for improved ocular retention of ketorolac tromethamine

    OpenAIRE

    Sunil Thakor; Imran Vhora; Jagruti Desai; Sneha Thakkar; Hetal Thakkar

    2012-01-01

    In present investigation, novel physiologically activated phase transition systems for Ketorolac Tromethamine was developed. In-situ gelling systems: pH sensitive gel using carbopol 980 and HPMC K100LV, ion sensitive gel using gallan gum and temperature sensitive gel using Poloxamer 407 and Poloxamer 188 were developed. The drug content, content uniformity, pH, optical transmittance, rheological property, bioadhesive strength, in-vitro drug release, ocular irritation and stability study were ...

  9. 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.

  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.

  11. 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...

  12. 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).

  13. What is the Origin of Activation Energy in Phase-Change Film?

    Science.gov (United States)

    Tominaga, Junji; Shima, Takayuku; Fons, Paul; Simpson, Robert; Kuwahara, Masashi; Kolobov, Alexander

    2009-03-01

    Activation energy is one of the basic parameters used to estimate the physical and chemical features of optical and electrical phase-change (PC) films. However, its origin has not been discussed well because of insufficient understanding of the amorphous structures. In this paper, we reveal the origin of the activation energy using a GeSbTe-superlattice model and ab-initio local density approximation (LDA) calculations. The simulated energy required for transition from amorphous to crystal formation in a 9-atomic system was 2.34 eV; This is in good agreement with experimentally reported values.

  14. 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.

  15. 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%.

  16. 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.

  17. Phase Change Activation and Characterization of Spray-Deposited Poly(vinylidene) Fluoride Piezoelectric Thin Films

    Science.gov (United States)

    Riosbaas, Miranda Tiffany

    Structural safety and integrity continues to be an issue of utmost concern in our world today. Existing infrastructures in civil, commercial, and military applications are beginning to see issues associated with age and environmental conditions. In addition, new materials are being put to service that are not yet fully characterized and understood when it comes to long term behavior. In order to assess the structural health of both old and new materials, it is necessary to implement a technique for monitoring wear and tear. Current methods that are being used today typically depend on visual inspection techniques or handheld instruments. These methods are not always ideal for large structures as they become very tedious leading to a substantial amount of both time and money spent. More recently, composite materials have been introduced into applications that can benefit from high strength-to-weight ratio materials. However, the use of more complex materials (such as composites) leads to a high demand of structural health monitoring techniques, since the damage is often internal and not visible to the naked eye. The work performed in this thesis examines the methods that can be used for phase change activation and characterization of sprayable poly(vinylidene) fluoride (PVDF) thin films in order to exploit their piezoelectric characteristics for sensing applications. PVDF is widely accepted to exist in four phases: alpha, beta, gamma, and delta. Alpha phase PVDF is produced directly from the melt and exhibits no piezoelectric properties. The activation or transition from α phase to some combination of beta and/or gamma phase PVDF leads to a polarizable piezoelectric thin film to be used in sensing applications. The work herein presents the methods used to activate phase change in PVDF, such as mechanical stretching, annealing, and chemical composition, to be able to implement PVDF as an impact detection sensor. The results and analysis provided in this thesis will

  18. 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.

  19. Zirconia supported catalysts for bioethanol steam reforming: Effect of active phase and zirconia structure

    Energy Technology Data Exchange (ETDEWEB)

    Benito, M.; Padilla, R.; Rodriguez, L.; Sanz, J.L.; Daza, L. [Instituto de Catalisis y Petroleoquimica (CSIC), C/ Marie Curie 2, Campus Cantoblanco, 28049 Madrid (Spain)

    2007-06-10

    Three new catalysts have been prepared in order to study the active phase influence in ethanol steam reforming reaction. Nickel, cobalt and copper were the active phases selected and were supported on zirconia with monoclinic and tetragonal structure, respectively. To characterize the behaviour of the catalysts in reaction conditions a study of catalytic activity with temperature was performed. The highest activity values were obtained at 973 K where nickel and cobalt based catalysts achieved an ethanol conversion of 100% and a selectivity to hydrogen close to 70%. Nickel supported on tetragonal zirconia exhibited the highest hydrogen production efficiency, higher than 4.5 mol H{sub 2}/mol EtOH fed. The influence of steam/carbon (S/C) ratio on product distribution was another parameter studied between the range 3.2-6.5. Nickel supported on tetragonal zirconia at S/C = 3.2 operated at 973 K without by-product production such as ethylene or acetaldehyde. In order to consider a further application in an ethanol processor, a long-term reaction experiment was performed at 973 K, S/C = 3.2 and atmospheric pressure. After 60 h, nickel supported on tetragonal zirconia exhibited high stability and selectivity to hydrogen production. (author)

  20. 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.

  1. Brain activation evoked by erotic films varies with different menstrual phases: an fMRI study.

    Science.gov (United States)

    Zhu, Xun; Wang, Xiaoying; Parkinson, Carolyn; Cai, Chengxu; Gao, Song; Hu, Peicheng

    2010-01-20

    In humans, fluctuating hormone levels throughout the menstrual cycle are believed to regulate many cyclical sexual behaviors and motivational processes. However, there is a dearth of research investigating the neural correlates of this phenomenon. We used functional magnetic resonance imaging to identify brain regions involved in sexual arousal's regulatory process. Fifteen female participants were scanned while viewing erotic film excerpts at three time points during a single menstrual cycle: ovulation, menstruation, and at one additional time point. Tripled two-group differences analysis revealed that significant activation in the comparison was observed in non-ovulatory phases of the menstrual cycle in parts of the right inferior frontal gyrus, right lateral occipital cortex, and left postcentral gyrus, as well as in the bilateral superior parietal lobule. Thus, our results indicate that brain activity differs in the ovulatory phase of the menstrual cycle compared to during other menstrual phases. This finding provides neurological evidence for the ovulatory cycle's modulation of the processing of the sexual arousal in female human brain.

  2. High Integrated Microwave Architecture Using LTCC-SIP Technology in Active Phased Array Antenna Applications

    Science.gov (United States)

    Zhou, Jun; Shi, Wei; Dou, Wen-Bin; Shen, Ya

    2012-06-01

    A kind of three dimensional Low Temperature Co-fired Ceramic (LTCC)-System in Package (SIP) transition was proposed in this paper. The basic design of SIP with LTCC technology was done by vertical transitions which transmit the microwave signal from the bottom to the surface of the substrate. The measured insertion loss did not exceed 1.5 dB, which contains the insertion loss of the test board about 0.6 dB at 18 GHz and the return loss was better than-15 dB up to 18 GHz. Then this technology was applied to a kind of phase shifting and amplifier module with two output ports. Basing on this module, a miniature Ku-band active phase array antenna was realized. The design results in a small size(84.8 mm×84.8 mm×55 mm). The measured performance of systems radiation pattern was also given.

  3. 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.

  4. 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.

  5. 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

  6. Segmentation and Tracking of Lymphocytes Based on Modified Active Contour Models in Phase Contrast Microscopy Images

    Directory of Open Access Journals (Sweden)

    Yali Huang

    2015-01-01

    Full Text Available The paper proposes an improved active contour model for segmenting and tracking accurate boundaries of the single lymphocyte in phase-contrast microscopic images. Active contour models have been widely used in object segmentation and tracking. However, current external-force-inspired methods are weak at handling low-contrast edges and suffer from initialization sensitivity. In order to segment low-contrast boundaries, we combine the region information of the object, extracted by morphology gray-scale reconstruction, and the edge information, extracted by the Laplacian of Gaussian filter, to obtain an improved feature map to compute the external force field for the evolution of active contours. To alleviate initial location sensitivity, we set the initial contour close to the real boundaries by performing morphological image processing. The proposed method was tested on live lymphocyte images acquired through the phase-contrast microscope from the blood samples of mice, and comparative experimental results showed the advantages of the proposed method in terms of the accuracy and the speed. Tracking experiments showed that the proposed method can accurately segment and track lymphocyte boundaries in microscopic images over time even in the presence of low-contrast edges, which will provide a good prerequisite for the quantitative analysis of lymphocyte morphology and motility.

  7. Active stabilization of a Michelson interferometer at an arbitrary phase with subnanometer resolution.

    Science.gov (United States)

    Grassani, Davide; Galli, Matteo; Bajoni, Daniele

    2014-04-15

    We report on the active stabilization of a Michelson interferometer at an arbitrary phase angle with a precision better than 1° at λ=632.8  nm, which corresponds to a precision in the optical path difference between the two arms of less than 1 nm. The stabilization method is ditherless, and the error signal is computed from the spatial shift of the interference pattern of a reference laser, measured in real-time with a CCD array detector. We discuss the usefulness of this method for nanopositioning, optical interferometry, and quantum optical experiments.

  8. 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...

  9. Indirect Control of a low power Single-Phase Active Power Filter

    Directory of Open Access Journals (Sweden)

    SILVIU EPURE

    2010-12-01

    Full Text Available This paper deals with a low power, single phase active filter used to compensate nonlinear loads. The filter uses the indirect control method and it is based on a particular connection between filter, polluting load and grid to avoid timeconsuming mathematic operations or signal processing computations and assures good rejection of harmonic currents injected by the nonlinear load into the grid. A scale model was first simulated in Simulink and then physically implemented. The paper presents simulation and experimental results, and highlight problems encountered during experiments.

  10. Three Super Active Regions in the Descending Phase of Solar Cycle 23

    Institute of Scientific and Technical Information of China (English)

    Hong-Qi Zhang; Jiang-Tao Su; Juan Guo; Xiao-Fan Wang; Ke-Liang Hu; Gang-Hua Lin; Dong-Guang Wang; Xing-Ming Bao; Yin Zhang; Ji-Hong Liu; Shu-Dong Bao; Yuan-Yong Deng; Wei Li; Jie Chen; Jin-Ping Dun

    2003-01-01

    We analyze the magnetic configurations of three super active regions,NOAA 10484, 10486 and 10488, observed by the Huairou Multi-Channel Solar Telescope (MCST) from 2003 October 18 to November 4. Many energetic phenomena,such as flares (including a X-28 flare) and coronal mass ejections (CMEs), occurred during this period. We think that strong shear and fast emergence of magnetic flux are the main causes of these events. The question is also of great interest why these dramatic eruptions occurred so close together in the descending phase of the solar cycle.

  11. Active stabilization of a Michelson interferometer at an arbitrary phase with sub-nm resolution

    CERN Document Server

    Grassani, Davide; Bajoni, Daniele

    2013-01-01

    We report on the active stabilization of a Michelson interferometer at an arbitrary phase angle with a precision better than one degree at $\\lambda = 632.8$ nm, which corresponds to an optical path difference between the two arms of less than 1 nm. The stabilization method is ditherless and the error signal is computed from the spatial shift of the interference pattern of a reference laser, measured in real-time with a CCD array detector. We discuss the usefulness of this method for nanopositioning, optical interferometry and quantum optical experiments.

  12. Active stabilization of a Michelson interferometer at an arbitrary phase with subnanometer resolution

    Science.gov (United States)

    Grassani, Davide; Galli, Matteo; Bajoni, Daniele

    2014-04-01

    We report on the active stabilization of a Michelson interferometer at an arbitrary phase angle with a precision better than one degree at $\\lambda = 632.8$ nm, which corresponds to an optical path difference between the two arms of less than 1 nm. The stabilization method is ditherless and the error signal is computed from the spatial shift of the interference pattern of a reference laser, measured in real-time with a CCD array detector. We discuss the usefulness of this method for nanopositioning, optical interferometry and quantum optical experiments.

  13. Single Phase Current-Source Active Rectifier for Traction: Control System Design and Practical Problems

    Directory of Open Access Journals (Sweden)

    Jan Michalik

    2006-01-01

    Full Text Available This research has been motivated by industrial demand for single phase current-source active rectifier dedicated for reconstruction of older types of dc machine locomotives. This paper presents converters control structure design and simulations. The proposed converter control is based on the mathematical model and due to possible interaction with railway signaling and required low switching frequency employs synchronous PWM. The simulation results are verified by experimental tests performed on designed laboratory prototype of power of 7kVA

  14. 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.

  15. 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

  16. 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....

  17. Neuro-Fuzzy based Controller for a Three- Phase Four-Wire Shunt Active Power Filter

    Directory of Open Access Journals (Sweden)

    Mridul Jha

    2011-10-01

    Full Text Available This paper describes the application of a novel neuro-fuzzy based control strategy which is used in order to improve the Active Power Filter (APF dynamics to minimize the harmonics for wide range of variations of load current under various conditions. To improve dynamic behavior of a three phase four-wire shunt active power filter and its robustness under range of load variations, adaptive hysteresis band with instantaneous p-q theory is used with the inclusion of neural network filter for reference current generation and fuzzy logic controller for DC voltage control. The proposed control scheme for “split-capacitor” converter topology is simple and also capable of maintaining the compensated line currents balanced, irrespective of unbalancing in the source voltages & deviation in the capacitor voltages. The results presented in MATLAB-SIMULINK software in this paper clearly reflect the effectiveness of the proposed APF to meet the IEEE-519 standard recommendations on harmonic levels.

  18. Solid-phase synthesis, characterization, and cellular activities of collagen-model nanodiamond-peptide conjugates.

    Science.gov (United States)

    Knapinska, Anna M; Tokmina-Roszyk, Dorota; Amar, Sabrina; Tokmina-Roszyk, Michal; Mochalin, Vadym N; Gogotsi, Yury; Cosme, Patrick; Terentis, Andrew C; Fields, Gregg B

    2015-05-01

    Nanodiamonds (NDs) have received considerable attention as potential drug delivery vehicles. NDs are small (∼5 nm diameter), can be surface modified in a controllable fashion with a variety of functional groups, and have little observed toxicity in vitro and in vivo. However, most biomedical applications of NDs utilize surface adsorption of biomolecules, as opposed to covalent attachment. Covalent modification provides reliable and reproducible ND-biomolecule ratios, and alleviates concerns over biomolecule desorption prior to delivery. The present study has outlined methods for the efficient solid-phase conjugation of ND to peptides and characterization of ND-peptide conjugates. Utilizing collagen-derived peptides, the ND was found to support or even enhance the cell adhesion and viability activities of the conjugated sequence. Thus, NDs can be incorporated into peptides and proteins in a selective manner, where the presence of the ND could potentially enhance the in vivo activities of the biomolecule it is attached to.

  19. 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...... switches result in DC-voltage at the transformer terminals. Even small DCvoltage components produce large DC-bias currents as they are only limited by the transformer resistances. The DC-bias degrades the transformer performance by increasing the losses. If the core saturates the resulting current pulses...... 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...

  20. 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 optica...... 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.......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...

  1. Modelling and Simulation of Single-Phase Series Active Compensator for Power Quality Improvement

    Science.gov (United States)

    Verma, Arun Kumar; Mathuria, Kirti; Singh, Bhim; Bhuvaneshwari, G.

    2016-10-01

    A single-phase active series compensator is proposed in this work to reduce harmonic currents at the ac mains and to regulate the dc link voltage of a diode bridge rectifier (DBR) that acts as the front end converter for a voltage source inverter feeding an ac motor. This ac motor drive is used in any of the domestic, commercial or industrial appliances. Under fluctuating ac mains voltages, the dc link voltage of the DBR depicts wide variations and hence the ac motor is used at reduced rating as compared to its name-plate rating. The active series compensator proposed here provides dual functions of improving the power quality at the ac mains and regulating the dc link voltage thus averting the need for derating of the ac motor.

  2. 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.

  3. 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.

  4. Co-Cu Nanoparticles: Synthesis by Galvanic Replacement and Phase Rearrangement during Catalytic Activation.

    Science.gov (United States)

    Nafria, Raquel; Genç, Aziz; Ibáñez, Maria; Arbiol, Jordi; de la Piscina, Pilar Ramírez; Homs, Narcís; Cabot, Andreu

    2016-03-08

    The control of the phase distribution in multicomponent nanomaterials is critical to optimize their catalytic performance. In this direction, while impressive advances have been achieved in the past decade in the synthesis of multicomponent nanoparticles and nanocomposites, element rearrangement during catalyst activation has been frequently overseen. Here, we present a facile galvanic replacement-based procedure to synthesize Co@Cu nanoparticles with narrow size and composition distributions. We further characterize their phase arrangement before and after catalytic activation. When oxidized at 350 °C in air to remove organics, Co@Cu core-shell nanostructures oxidize to polycrystalline CuO-Co3O4 nanoparticles with randomly distributed CuO and Co3O4 crystallites. During a posterior reduction treatment in H2 atmosphere, Cu precipitates in a metallic core and Co migrates to the nanoparticle surface to form Cu@Co core-shell nanostructures. The catalytic behavior of such Cu@Co nanoparticles supported on mesoporous silica was further analyzed toward CO2 hydrogenation in real working conditions.

  5. 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

  6. OCT intensity and phase fluctuations correlated with activity-dependent neuronal calcium dynamics in the Drosophila CNS [Invited

    Science.gov (United States)

    Tong, Minh Q.; Hasan, Md. Monirul; Lee, Sang Soo; Haque, Md. Rezuanul; Kim, Do-Hyoung; Islam, Md. Shahidul; Adams, Michael E.; Park, B. Hyle

    2017-01-01

    Phase-resolved OCT and fluorescence microscopy were used simultaneously to examine stereotypic patterns of neural activity in the isolated Drosophila central nervous system. Both imaging modalities were focused on individually identified bursicon neurons known to be involved in a fixed action pattern initiated by ecdysis-triggering hormone. We observed clear correspondence of OCT intensity, phase fluctuations, and activity-dependent calcium-induced fluorescence.

  7. Solid phase extraction of uranium(VI) onto benzoylthiourea-anchored activated carbon.

    Science.gov (United States)

    Zhao, Yongsheng; Liu, Chunxia; Feng, Miao; Chen, Zhen; Li, Shuqiong; Tian, Gan; Wang, Li; Huang, Jingbo; Li, Shoujian

    2010-04-15

    A new solid phase extractant selective for uranium(VI) based on benzoylthiourea anchored to activated carbon was developed via hydroxylation, amidation and reaction with benzoyl isothiocyanate in sequence. Fourier transform infrared spectroscopy and total element analysis proved that benzoylthiourea had been successfully grafted to the surface of the activated carbon, with a loading capacity of 1.2 mmol benzoylthiourea per gram of activated carbon. The parameters that affect the uranium(VI) sorption, such as contact time, solution pH, initial uranium(VI) concentration, adsorbent dose and temperature, have been investigated. Results have been analyzed by Langmuir and Freundlich isotherm; the former was more suitable to describe the sorption process. The maximum sorption capacity (82 mg/g) for uranium(VI) was obtained at experimental conditions. The rate constant for the uranium sorption by the as-synthesized extractant was 0.441 min(-1) from the first order rate equation. Thermodynamic parameters (DeltaH(0)=-46.2 kJ/mol; DeltaS(0)=-98.0 J/mol K; DeltaG(0)=-17.5 kJ/mol) showed the adsorption of an exothermic process and spontaneous nature, respectively. Additional studies indicated that the benzoylthiourea-anchored activated carbon (BT-AC) selectively sorbed uranyl ions in the presence of competing ions, Na(+), Co(2+), Sr(2+), Cs(+) and La(3+).

  8. 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.

  9. 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.

  10. Treatment of aqueous phase of bio-oil by granular activated carbon and evaluation of biogas production.

    Science.gov (United States)

    Shanmugam, Saravanan R; Adhikari, Sushil; Wang, Zhouhang; Shakya, Rajdeep

    2017-01-01

    Hydrothermal liquefaction of wet biomass such as algae is a promising thermochemical process for the production of bio-oil. Bio-oil aqueous phase generated during liquefaction process is rich in complex organics and can be utilized for biogas production following its pre-treatment with granular activated carbon. In our study, use of 30% activated carbon resulted in higher chemical oxygen demand (COD) reduction (53±0.3%) from aqueous phase. Higher CH4 production (84±12mL/gCOD) was also observed in 30% carbon-treated aqueous phase fed cultures, whereas only 32±6mLCH4/gCOD was observed in control (non-carbon treated) cultures. The results from this study indicate that almost 67±0.3% initial COD of aqueous phase can be reduced using a combination of both carbon treatment and biogas production. This study shows that aqueous phase can be utilized for CH4 production.

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

    OpenAIRE

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

    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 estimate the active/reactive power values. The proposed control system enables the hybrid renewable energy generation system to be able to perform real-time grid interconnection services such as active v...

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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...

  17. 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.

  18. Antimicrobial Activity from Colistin-Heparin Lamellar-Phase Complexes for the Coating of Biomedical Devices.

    Science.gov (United States)

    Tangso, Kristian J; C D da Cunha, Paulo Henrique; Spicer, Patrick; Li, Jian; Boyd, Ben J

    2016-11-16

    Infections arising in hospitalized patients, particularly those who have undergone surgery and are reliant on receiving treatment through biomedical devices, continue to be a rising concern. It is well-known that aqueous mixtures of oppositely charged surfactant and polymer molecules can self-assemble to form liquid crystalline structures, primarily via electrostatically driven interactions that have demonstrated great potential as tailored-release nanomaterials. Colistin is a re-emerging antibiotic used against multidrug-resistant Gram-negative bacteria. Its amphiphilic structure allows it to form micellar aggregates in solution. Thus, the aim of this study was to determine whether structured complexes form between colistin and negatively charged biopolymers, such as the highly sulfated anticoagulant, heparin. Cross-polarized light microscopy and synchrotron small-angle X-ray scattering were employed to visualize the appearance of birefringent structures and identify liquid crystalline structures, respectively, formed across the interface between solutions of colistin and heparin. A lamellar phase with a lattice parameter of ∼40 Å was formed upon contact between the oppositely charged solutions of colistin and heparin. In addition, in vitro release studies showed a slow release of colistin from the lamellar-phase gel complexes into the bulk media, and disk diffusion bioassays revealed antimicrobial activity against Pseudomonas aeruginosa. This system provides a novel, cost-effective, and simple approach to reducing the risk of infections by potentially applying the formulation as a coating for biomedical implants or tubing.

  19. Photoelectrochemical activity of liquid phase deposited TiO2 film for degradation of benzotriazole.

    Science.gov (United States)

    Ding, Yaobin; Yang, Changzhu; Zhu, Lihua; Zhang, Jingdong

    2010-03-15

    TiO(2) film deposited on glassy carbon electrode surface was prepared via the liquid phase deposition (LPD). The deposited TiO(2) film before and after calcination was characterized with scanning electron microscopy (SEM) and X-ray diffraction (XRD). Based on the high photoelectrochemical activity of calcined LPD TiO(2) film, the photoelectrocatalytic degradation of benzotriazole (BTA) was investigated. Compared with the electrochemical oxidation process, direct photolysis or photocatalysis for treatment of BTA, a synergetic photoelectrocatalytic degradation effect was observed using the LPD TiO(2) film-coated electrode. Various factors influencing the photoelectrocatalytic degradation of BTA such as film calcination, applied bias potential, pH value, supporting electrolyte concentration and initial concentration of BTA were investigated. The COD removal for BTA solution was analyzed to evaluate the mineralization of the PEC process. Based on the degradation experimental results, a possible photoelectrocatalytic degradation mechanism for BTA was proposed.

  20. Photoelectrochemical activity of liquid phase deposited TiO{sub 2} film for degradation of benzotriazole

    Energy Technology Data Exchange (ETDEWEB)

    Ding Yaobin [College of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan 430074 (China); Yang Changzhu [College of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Zhu Lihua [College of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan 430074 (China); Zhang Jingdong, E-mail: zhangjd@mail.hust.edu.cn [College of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan 430074 (China)

    2010-03-15

    TiO{sub 2} film deposited on glassy carbon electrode surface was prepared via the liquid phase deposition (LPD). The deposited TiO{sub 2} film before and after calcination was characterized with scanning electron microscopy (SEM) and X-ray diffraction (XRD). Based on the high photoelectrochemical activity of calcined LPD TiO{sub 2} film, the photoelectrocatalytic degradation of benzotriazole (BTA) was investigated. Compared with the electrochemical oxidation process, direct photolysis or photocatalysis for treatment of BTA, a synergetic photoelectrocatalytic degradation effect was observed using the LPD TiO{sub 2} film-coated electrode. Various factors influencing the photoelectrocatalytic degradation of BTA such as film calcination, applied bias potential, pH value, supporting electrolyte concentration and initial concentration of BTA were investigated. The COD removal for BTA solution was analyzed to evaluate the mineralization of the PEC process. Based on the degradation experimental results, a possible photoelectrocatalytic degradation mechanism for BTA was proposed.

  1. 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...

  2. Physiologically activated phase transition systems for improved ocular retention of ketorolac tromethamine.

    Science.gov (United States)

    Thakor, Sunil; Vhora, Imran; Desai, Jagruti; Thakkar, Sneha; Thakkar, Hetal

    2012-03-01

    In present investigation, novel physiologically activated phase transition systems for Ketorolac Tromethamine was developed. In-situ gelling systems: pH sensitive gel using carbopol 980 and HPMC K100LV, ion sensitive gel using gallan gum and temperature sensitive gel using Poloxamer 407 and Poloxamer 188 were developed. The drug content, content uniformity, pH, optical transmittance, rheological property, bioadhesive strength, in-vitro drug release, ocular irritation and stability study were evaluated. Characterization revealed that gels were conforming to all criteria required for ocular delivery in terms of stability on sterilization, long residence time, non-irritability and sustained drug release without affecting vision. Thus, In-situ gels can be a promising alternative to the prevalent market formulations.

  3. Physiologically activated phase transition systems for improved ocular retention of ketorolac tromethamine

    Directory of Open Access Journals (Sweden)

    Sunil Thakor

    2012-01-01

    Full Text Available In present investigation, novel physiologically activated phase transition systems for Ketorolac Tromethamine was developed. In-situ gelling systems: pH sensitive gel using carbopol 980 and HPMC K100LV, ion sensitive gel using gallan gum and temperature sensitive gel using Poloxamer 407 and Poloxamer 188 were developed. The drug content, content uniformity, pH, optical transmittance, rheological property, bioadhesive strength, in-vitro drug release, ocular irritation and stability study were evaluated. Characterization revealed that gels were conforming to all criteria required for ocular delivery in terms of stability on sterilization, long residence time, non-irritability and sustained drug release without affecting vision. Thus, In-situ gels can be a promising alternative to the prevalent market formulations.

  4. 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.

  5. 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.

  6. 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.

  7. Facile synthesis and photocatalytic activity of bi-phase dispersible Cu-ZnO hybrid nanoparticles.

    Science.gov (United States)

    Liu, Xiao; Liu, HongLing; Zhang, WenXing; Li, XueMei; Fang, Ning; Wang, XianHong; Wu, JunHua

    2015-01-01

    Bi-phase dispersible Cu-ZnO hybrid nanoparticles were synthesized by one-pot non-aqueous nanoemulsion with the use of poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (PEO-PPO-PEO) as the surfactant. The transmission electron microscopy (TEM) and X-ray diffraction (XRD) show high crystallinity of the Cu-ZnO hybrid nanoparticles and an average particle size of ~19.4 nm. The ultraviolet-visible light absorbance spectrometry (UV-vis) and photoluminescence spectrophotometry (PL) demonstrate well dispersibility and excellent optical performance of Cu-ZnO hybrid nanoparticles both in organic and aqueous solvent. The X-ray photoelectron spectroscopy (XPS) confirms Cu(1+) and Cu(2+) in ZnO. The observation using Sudan red (III) as probe molecule reveals that the Cu-ZnO hybrid nanoparticles possess enhanced photocatalytic activity and stability which are promising for potential applications in photocatalysis.

  8. Controlling kilometre-scale interferometric detectors for gravitational wave astronomy: Active phase noise cancellation using EOMs

    Science.gov (United States)

    Arnaud, N.; Balembois, L.; Bizouard, M. A.; Brisson, V.; Casanueva, J.; Cavalier, F.; Davier, M.; Frey, V.; Hello, P.; Huet, D.; Leroy, N.; Loriette, V.; Maksimovic, I.; Robinet, F.

    2017-02-01

    The second generation of Gravitational waves detectors are kilometric Michelson interferometers with additional recycling Fabry-Perot cavities on the arms and ​the addition of two more recycling cavities to enhance their sensitivity, with the particularity that all the mirrors are suspended. In order to control them a new technique, based on the use of auxiliary lasers, has been developed to bring the interferometer to its working point, with all the cavities on their resonance, in an adiabatic way. The implementation of this technique in Advanced Virgo is under preparation and the propagation of a stable laser through a 3-km optical fibre is one of the most problematic issues. A new technique of active phase noise cancellation based on the use of Electro Optical Modulators has been developed, and a first prototype has been successfully tested.

  9. 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.

  10. Gas phase tricholoethylene removal at low concentration using activated carbon fiber

    Institute of Scientific and Technical Information of China (English)

    LIU Jun; HUANG Zheng-hong; WANG Zhan-sheng; KANG Fei-yu

    2004-01-01

    The breakthrough adsorption behaviors of gas phase trichloroethylene in a packed bed of activated carbon fibers(ACF) were investigated. The specific surface area of the ACF was 600 m2/g, 1400 m2/g and 1600 m2/g, respectively, and the concentration of trichioroethylene ranged from 270 mg/m3 to 2700 mg/m3 . Results showed that the capacity of adsorption increased with increasing specific surface area, the relationship between the logarithms of 10% breakthrough time and concentration was approximately linear over the experimental range, the breakthrough time decreased with increasing temperature and humidity. The breakthrough curves at different inlet concentration or different temperature can be predicted by several simple theoretical models with good agreements.

  11. Predictive Duty Cycle Control of Three-Phase Active-Front-End Rectifiers

    DEFF Research Database (Denmark)

    Song, Zhanfeng; Tian, Yanjun; Chen, Wei;

    2016-01-01

    of optimal duty cycles is made by predicting the effect of duty cycles on instantaneous current variations and minimizing the cost function. Due to the adoption of behavior prediction, the proposed controller inherits the excellent dynamic characteristics of predictive controllers. Moreover, the application......This paper proposed an on-line optimizing duty cycle control approach for three-phase active-front-end rectifiers, aiming to obtain the optimal control actions under different operating conditions. Similar to finite control set model predictive control strategy, a cost function previously...... of optimal duty cycles determined by cost function minimization automatically ensures optimum operations of converters within each sampling period. Improved transient and steady-state features of the proposed strategy are confirmed by experimental validations and in-depth comparisons with linear controllers...

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

    Science.gov (United States)

    Li, Ling; Jin, Zhen-Lan; Li, Bin

    2011-03-01

    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. Project supported by the Young Scientists Fund of the National Natural Science Foundation of China (Grant No. 30800242). yCorresponding author. E-mail: libin@uestc.edu.cn

  13. 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.

  14. 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…

  15. 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

  16. 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

  17. Separation of active laccases from Pleurotus sapidus culture supernatant using aqueous two-phase systems in centrifugal partition chromatography.

    Science.gov (United States)

    Schwienheer, C; Prinz, A; Zeiner, T; Merz, J

    2015-10-01

    For the production of bio active compounds, e.g., active enzymes or antibodies, a conserved purification process with a minimum loss of active compounds is necessary. In centrifugal partition chromatography (CPC), the separation effect is based on the different distribution of the components to be separated between two immiscible liquid phases. Thereby, one liquid phase is kept stationary in chambers by a centrifugal field and the mobile phase is pumped through via connecting ducts. Aqueous two phase systems (ATPS) are known to provide benign conditions for biochemical products and seem to be promising when used in CPC for purification tasks. However, it is not known if active biochemical compounds can "survive" the conditions in a CPC where strong shear forces can occur due to the two-phasic flow under centrifugal forces. Therefore, this aspect has been faced within this study by the separation of active laccases from a fermentation broth of Pleurotus sapidus. After selecting a suitable ATPS and operating conditions, the activity yield was calculated and the preservation of the active enzymes could be observed. Therefore, CPC could be shown as potentially suitable for the purification of bio-active compounds.

  18. IDENTIFICATION OF PHASE COMPOSITION OF BINDERS FROM ALKALI-ACTIVATED MIXTURES OF GRANULATED BLAST FURNACE SLAG AND FLY ASH

    Directory of Open Access Journals (Sweden)

    JOZEF VLČEK

    2014-03-01

    Full Text Available The prepared alkali-activated binders (AAB and composites using suitable latent hydraulic raw materials represent an alternative to materials based on Portland cements. This paper deals with ways how to influence the functional parameters of AAB by setting up mixtures of granulated blast furnace slag (GBFS and fly ash with selected chemical compositions. In this way the course of hydration process is modified and the phase composition of products of alkali activation is changed as well as their final properties. The amorphous character of the hydration products makes evaluation of the phase composition of hardened AAB difficult and significantly limits the number of experimental techniques suitable to characterise their phase composition. It was observed that measuring the pH of water extracts obtained from the alkali-activated mixtures can give supplementary information about the process of hardening of alkali-activated mixtures of GBFS and fly ash.

  19. The effect of gas plasma modification on platelet and contact phase activation processes.

    Science.gov (United States)

    Rhodes, Nicholas P; Wilson, Darren J; Williams, Rachel L

    2007-11-01

    Medical-grade polytetrafluoroethylene (PTFE), polydimethylsiloxane (PDMS), polyetherurethane (PEU) and ultrahigh molecular weight polyethylene (UHMWPE) were plasma treated with O2, Ar, N2 and NH3. Their surface properties were characterised using X-ray photoelectron spectroscopy (XPS), static secondary ion mass spectroscopy (SSIMS), atomic force microscopy (AFM) and dynamic contact angle (DCA) analysis. Platelet adhesion, aggregation, activation and release of microparticles were determined after contact with whole blood in a cone and plate viscometer. Activation of the coagulation system was quantified in a static environment using a partial thromboplastin time (PTT) assay. The chemical compositions of the untreated surfaces were found to be very similar to those of the bulk material except for PEU, whose surface was comprised almost entirely of soft ether segments. For all materials, the different plasma treatments resulted in moderate etching with the incorporation of functional groups and removal of side groups: defluorination, dehydrogenation, cleavage of methyl side groups and soft segments for PTFE, UHMWPE, PDMS and PEU, respectively. Consequently, plasma treatment resulted in increased wettability in all cases. Blood contact with the virgin materials resulted in activation of platelets and the clotting cascade. Plasma treatment resulted in a significant reduction in platelet adhesion for all materials and all treatments. In the case of PTFE and PEU, the activation status of these cells was also reduced. Plasma treatment of all materials reduced fluid-phase CD62P expression. Platelet aggregate size correlated well with degree of aggregate formation, but many treatments increased the degree of aggregation, as was the case for microparticle shedding. There was no correlation between CD62P expression, aggregate formation and platelet microparticle (PMP) shedding. It is concluded that despite incorporation of the same chemical groups, the pattern of response to

  20. 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}.

  1. 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.

  2. Altering the interfacial activation mechanism of a lipase by solid-phase selective chemical modification.

    Science.gov (United States)

    López-Gallego, Fernando; Abian, Olga; Guisán, Jose Manuel

    2012-09-04

    This study presents a combined protein immobilization, directed mutagenesis, and site-selective chemical modification approach, which was used to create a hyperactivated semisynthetic variant of BTL2. Various alkane chains were tethered at three different positions in order to mimic the lipase interfacial activation exogenously triggered by detergents. Optimum results were obtained when a dodecane chain was introduced at position 320 by solid-phase site-selective chemical modification. The resulting semisynthetic variant showed a 2.5-fold higher activity than the wild-type nonmodified variant in aqueous conditions. Remarkably, this is the maximum hyperactivation ever observed for BTL2 in the presence of detergents such as Triton X-100. We present evidence to suggest that the endogenous dodecane chain hyperactivates the enzyme in a similar fashion as an exogenous detergent molecule. In this way, we also observe a faster irreversible enzyme inhibition and an altered detergent sensitivity profile promoted by the site-selective chemical modification. These findings are also supported by fluorescence studies, which reveal that the structural conformation changes of the semisynthetic variant are different to those of the wild type, an effect that is more pronounced in the presence of detergent. Finally, the optimal immobilized semisynthetic variant was successfully applied to the selective synthesis of oxiran-2-yl butyrate. Significantly, this biocatalyst is 12-fold more efficient than the immobilized wild-type enzyme, producing the S-enantiomer with higher enantiospecificity (ee = 92%).

  3. Prominent catalytic activity of mesoporous molecular sieves in the vapor phase dehydration of cyclohexanol to cyclohexene

    Institute of Scientific and Technical Information of China (English)

    Azhagapillai Prabhu; Ahmed Al Shoaibi; Chandrasekar Srinivasakannan; Muthaiahpillai Palanichamy; Velayutham Murugesan

    2013-01-01

    Cerium incorporated KIT-6 mesoporous materials were synthesized through direct hydrothermal method and characterized by using X-ray diffraction (XRD),nitrogen sorption isotherm (BET),Fourier transform infrared spectroscopy (FT-IR),inductively coupled plasma-atomic emission spectroscopy (ICP-AES),diffuse reflectance ultraviolet visible spectroscopy (DRS-UV-Vis),thermogravimetric analysis (TGA),scanning electron microscopy (SEM) and transmission electron microscopy (TEM) methods.It appeared that stable cerium ions were inserted into the silica framework of KIT-6,thus generating acid properties in their host materials.The catalytic activity of Ce-KIT-6 materials was evaluated in the vapor phase dehydration of cyclohexanol to cyclohexene and dicyclohexyl ether at different temperatures with various Si/Ce molar ratios.Ce-KIT-6 (25) showed higher activity with 54% cyclohexanol conversion and 64% selectivity to cyclohexene.The catalytic results indicated that Ce-KIT-6 mesoporous materials could be used as versatile and stable acid catalysts.

  4. 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.

  5. 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.

  6. 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

  7. Activation of alpha chymotrypsin by three phase partitioning is accompanied by aggregation.

    Science.gov (United States)

    Rather, Gulam Mohmad; Mukherjee, Joyeeta; Halling, Peter James; Gupta, Munishwar Nath

    2012-01-01

    Precipitation of alpha chymotrypsin in the simultaneous presence of ammonium sulphate and t-butanol (three phase partitioning) resulted in preparations which showed self aggregation of the enzyme molecules. Precipitation with increasing amounts of ammonium sulphate led to increasing size of aggregates. While light scattering estimated the hydrodynamic diameter of these aggregates in the range of 242-1124 nm; Nanoparticle tracking analysis (NTA) gave the value as 130-462 nm. Scanning electron microscopy and gel filtration on Sephadex G-200 showed extensive aggregation in these preparations. Transmission electron microscopy showed that the aggregates had irregular shapes. All the aggregates had about 3× higher catalytic activity than the native enzyme. These aggregates did not differ in λ(max) of fluorescence emission which was around 340 nm. However, all the aggregates showed higher fluorescence emission intensity. Far-UV and near-UV circular dichroism also showed no significant structural changes as compared to the native molecule. Interestingly, HPLC gel filtration (on a hydroxylated silica column) gave 14 nm as the diameter for all preparations. Light scattering of preparations in the presence of 10% ethylene glycol also dissociated the aggregates to monomers of 14 nm. Both these results indicated that hydrophobic interactions were the driving force behind this aggregation. These results indicate: (1) Even without any major structural change, three phase partitioning led to protein molecules becoming highly prone to aggregation. (2) Different methods gave widely different estimates of sizes of aggregates. It was however possible to reconcile the data obtained with various approaches. (3) The nature of the gel filtration column is crucial and use of this technique for refolding and studying aggregation needs a rethink.

  8. Activation of alpha chymotrypsin by three phase partitioning is accompanied by aggregation.

    Directory of Open Access Journals (Sweden)

    Gulam Mohmad Rather

    Full Text Available Precipitation of alpha chymotrypsin in the simultaneous presence of ammonium sulphate and t-butanol (three phase partitioning resulted in preparations which showed self aggregation of the enzyme molecules. Precipitation with increasing amounts of ammonium sulphate led to increasing size of aggregates. While light scattering estimated the hydrodynamic diameter of these aggregates in the range of 242-1124 nm; Nanoparticle tracking analysis (NTA gave the value as 130-462 nm. Scanning electron microscopy and gel filtration on Sephadex G-200 showed extensive aggregation in these preparations. Transmission electron microscopy showed that the aggregates had irregular shapes. All the aggregates had about 3× higher catalytic activity than the native enzyme. These aggregates did not differ in λ(max of fluorescence emission which was around 340 nm. However, all the aggregates showed higher fluorescence emission intensity. Far-UV and near-UV circular dichroism also showed no significant structural changes as compared to the native molecule. Interestingly, HPLC gel filtration (on a hydroxylated silica column gave 14 nm as the diameter for all preparations. Light scattering of preparations in the presence of 10% ethylene glycol also dissociated the aggregates to monomers of 14 nm. Both these results indicated that hydrophobic interactions were the driving force behind this aggregation. These results indicate: (1 Even without any major structural change, three phase partitioning led to protein molecules becoming highly prone to aggregation. (2 Different methods gave widely different estimates of sizes of aggregates. It was however possible to reconcile the data obtained with various approaches. (3 The nature of the gel filtration column is crucial and use of this technique for refolding and studying aggregation needs a rethink.

  9. Potential and optimization of two-phase anaerobic digestion of oil refinery waste activated sludge and microbial community study

    Science.gov (United States)

    Wang, Qinghong; Liang, Ying; Zhao, Peng; Li, Qing X.; Guo, Shaohui; Chen, Chunmao

    2016-12-01

    Oil refinery waste activated sludge produced from oil wastewater biological treatment is a major industrial sludge. Two-phase anaerobic digestion of oil refinery waste activated sludge was studied for the first time. Thermal pretreatment under 170 °C is effective on sludge solubilization. At the optimum hydrolytic-acidogenic condition which was pH of 6.5, temperature of 55 °C and HRT of 2 days, 2754 mg/L volatile fatty acids (VFAs) were produced and acetic acid and butyric acid were the key components. Comparative studies of single-phase and two-phase anaerobic digestion in terms of organic removal, biogas production and methane concentration were conducted. The cumulative methane production and soluble COD (SCOD) removal efficiency in the two-phase system were 228 mL/g COD added and 77.8%, respectively, which were 1.6 and 2.1 times higher than those in single-phase anaerobic digestion. Such improved performance is attributed to intensification of dominant microbial population in separated reactors. Caloramator, Ureibacillus, Dechloromonas, Petrobacter, and T78 played important roles in hydrolytic-acidification and oil-organics degradation. Syntrophic bacteria in the family Porphyromonadaceae and the genus Anaerobranca provide acetate for methanogen. The results demonstrated the potential and operating condition of two-phase anaerobic digestion in treatment of oil refinery waste activated sludge.

  10. Potential and optimization of two-phase anaerobic digestion of oil refinery waste activated sludge and microbial community study.

    Science.gov (United States)

    Wang, Qinghong; Liang, Ying; Zhao, Peng; Li, Qing X; Guo, Shaohui; Chen, Chunmao

    2016-12-01

    Oil refinery waste activated sludge produced from oil wastewater biological treatment is a major industrial sludge. Two-phase anaerobic digestion of oil refinery waste activated sludge was studied for the first time. Thermal pretreatment under 170 °C is effective on sludge solubilization. At the optimum hydrolytic-acidogenic condition which was pH of 6.5, temperature of 55 °C and HRT of 2 days, 2754 mg/L volatile fatty acids (VFAs) were produced and acetic acid and butyric acid were the key components. Comparative studies of single-phase and two-phase anaerobic digestion in terms of organic removal, biogas production and methane concentration were conducted. The cumulative methane production and soluble COD (SCOD) removal efficiency in the two-phase system were 228 mL/g COD added and 77.8%, respectively, which were 1.6 and 2.1 times higher than those in single-phase anaerobic digestion. Such improved performance is attributed to intensification of dominant microbial population in separated reactors. Caloramator, Ureibacillus, Dechloromonas, Petrobacter, and T78 played important roles in hydrolytic-acidification and oil-organics degradation. Syntrophic bacteria in the family Porphyromonadaceae and the genus Anaerobranca provide acetate for methanogen. The results demonstrated the potential and operating condition of two-phase anaerobic digestion in treatment of oil refinery waste activated sludge.

  11. Potential and optimization of two-phase anaerobic digestion of oil refinery waste activated sludge and microbial community study

    Science.gov (United States)

    Wang, Qinghong; Liang, Ying; Zhao, Peng; Li, Qing X.; Guo, Shaohui; Chen, Chunmao

    2016-01-01

    Oil refinery waste activated sludge produced from oil wastewater biological treatment is a major industrial sludge. Two-phase anaerobic digestion of oil refinery waste activated sludge was studied for the first time. Thermal pretreatment under 170 °C is effective on sludge solubilization. At the optimum hydrolytic-acidogenic condition which was pH of 6.5, temperature of 55 °C and HRT of 2 days, 2754 mg/L volatile fatty acids (VFAs) were produced and acetic acid and butyric acid were the key components. Comparative studies of single-phase and two-phase anaerobic digestion in terms of organic removal, biogas production and methane concentration were conducted. The cumulative methane production and soluble COD (SCOD) removal efficiency in the two-phase system were 228 mL/g COD added and 77.8%, respectively, which were 1.6 and 2.1 times higher than those in single-phase anaerobic digestion. Such improved performance is attributed to intensification of dominant microbial population in separated reactors. Caloramator, Ureibacillus, Dechloromonas, Petrobacter, and T78 played important roles in hydrolytic-acidification and oil-organics degradation. Syntrophic bacteria in the family Porphyromonadaceae and the genus Anaerobranca provide acetate for methanogen. The results demonstrated the potential and operating condition of two-phase anaerobic digestion in treatment of oil refinery waste activated sludge. PMID:27905538

  12. 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...... estimate the active/reactive power values. The proposed control system enables the hybrid renewable energy generation system to be able to perform real-time grid interconnection services such as active voltage regulation, active power control, and fault ride-through.Simulation and experimental results...... demonstrate the superior performance of the proposed closed-loop control system....

  13. 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

  14. 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.

  15. Food intake during the normal activity phase prevents obesity and circadian desynchrony in a rat model of night work.

    Science.gov (United States)

    Salgado-Delgado, Roberto; Angeles-Castellanos, Manuel; Saderi, Nadia; Buijs, Ruud M; Escobar, Carolina

    2010-03-01

    Shift work or night work is associated with hypertension, metabolic syndrome, cancer, and other diseases. The cause for these pathologies is proposed to be the dissociation between the temporal signals from the biological clock and the sleep/activity schedule of the night worker. We investigated the mechanisms promoting metabolic desynchrony in a model for night work in rats, based on daily 8-h activity schedules during the resting phase. We demonstrate that the major alterations leading to internal desynchrony induced by this working protocol, flattened glucose and locomotor rhythms and the development of abdominal obesity, were caused by food intake during the rest phase. Shifting food intake to the normal activity phase prevented body weight increase and reverted metabolic and rhythmic disturbances of the shift work animals to control ranges. These observations demonstrate that feeding habits may prevent or induce internal desynchrony and obesity.

  16. Mesoporous mixed-phase Ga{sub 2}O{sub 3}: Green synthesis and enhanced photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jin [School of Resources and Environmental Engineering, Wuhan University of Technology, 122 Luoshi Road, Wuhan 430070 (China); The Key Laboratory of Rare Earth Functional Materials and Applications, Zhoukou Normal University, Zhoukou 466001 (China); Zhang, Gaoke, E-mail: gkzhang@whut.edu.cn [School of Resources and Environmental Engineering, Wuhan University of Technology, 122 Luoshi Road, Wuhan 430070 (China)

    2015-08-15

    Highlights: • Mixed-phase Ga{sub 2}O{sub 3} was synthesized by a facile and green method. • Mixed-phase Ga{sub 2}O{sub 3} exhibited good photocatalytic activity and stability. • The reactive species in the photocatalytic process were investigated. - Abstract: Mesoporous mixed-phase Ga{sub 2}O{sub 3} was synthesized by calcining the GaOOH precursor. The composition, crystal phase and microstructures of Ga{sub 2}O{sub 3} were characterized in detail. The phase composition of the as-prepared Ga{sub 2}O{sub 3} depended on the calcination temperature and the mixed-phase Ga{sub 2}O{sub 3} was obtained at 600–700 °C. As compared to the pure-phase α-Ga{sub 2}O{sub 3} and β-Ga{sub 2}O{sub 3}, the mixed-phase Ga{sub 2}O{sub 3} exhibited an enhanced photocatalytic property for the degradation of metronidazole solution. The heterojunction in the mixed-phase Ga{sub 2}O{sub 3} was beneficial to the separation of photogenerated electrons and holes. Moreover, the mixed-phase Ga{sub 2}O{sub 3} possessed mesopore structure, which increased more reaction sites and was in favor of the contact of metronidazole molecules with reaction sites. The recycling experiments show that the mixed-phase Ga{sub 2}O{sub 3} has good stability and can be separated easily from the reaction system.

  17. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Li Jie; Wang Tiecheng; Lu Na; Zhang Dandan; Wu Yan; Wang Tianwei [Institute of Electrostatic and Special Power, Dalian University of Technology, Dalian 116024 (China); Sato, Masayuki, E-mail: lijie@dlut.edu.cn [Department of Chemical and Environmental Engineering, Gunma University, Kiryu, Tenjin-cho 1-5-1, 376-8515 (Japan)

    2011-06-15

    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. Combined feedforward and model-assisted active disturbance rejection control for non-minimum phase system.

    Science.gov (United States)

    Sun, Li; Li, Donghai; Gao, Zhiqiang; Yang, Zhao; Zhao, Shen

    2016-09-01

    Control of the non-minimum phase (NMP) system is challenging, especially in the presence of modelling uncertainties and external disturbances. To this end, this paper presents a combined feedforward and model-assisted Active Disturbance Rejection Control (MADRC) strategy. Based on the nominal model, the feedforward controller is used to produce a tracking performance that has minimum settling time subject to a prescribed undershoot constraint. On the other hand, the unknown disturbances and uncertain dynamics beyond the nominal model are compensated by MADRC. Since the conventional Extended State Observer (ESO) is not suitable for the NMP system, a model-assisted ESO (MESO) is proposed based on the nominal observable canonical form. The convergence of MESO is proved in time domain. The stability, steady-state characteristics and robustness of the closed-loop system are analyzed in frequency domain. The proposed strategy has only one tuning parameter, i.e., the bandwidth of MESO, which can be readily determined with a prescribed robustness level. Some comparative examples are given to show the efficacy of the proposed method. This paper depicts a promising prospect of the model-assisted ADRC in dealing with complex systems.

  20. Phenolic Wastewater Treatment using Activated Carbon in a Three Phase Fluidized-Bed Reactor

    Directory of Open Access Journals (Sweden)

    Pornsiri Tongprem

    2009-11-01

    Full Text Available Phenolic wastewater treatment was investigated using activated carbon in a lab scale three phase fluidized-bed reactor. The reactor with effective volume of 272 ml, 300 mm in height and 40 mm in diameter was made from transparent acrylic that allowed to observe the phenomena occurring inside. Phenol 10 mg/l and air were used as representative agents that were continuously fed to the reactor at a constant flow rate of 1 and 2 l/min with co-current and up-flow, respectively. Comparison of the phenolic adsorption under five different conditions: (a fresh Acs, (b 1st reused Acs, (c fresh Fe/Acs, (d 1st reused Fe/Acs, and (e 2nd reused Fe/Acs, have been carried out. The phenolic wastewater was re-circulated through the reactor and its concentration was measured with respect to time. The experimental adsorption results revealed that both fresh Acs and Fe/Acs gave the better results than reused Acs and reused Fe/Acs, respectively. The adsorption in all cases of Acs and Fe/Acs would follow Pseudo-second order kinetic.

  1. 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.

  2. 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.

  3. 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.

  4. 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

    to reproduce the main feature of an unbalanced grid. The experimental activities are recreated in by carrying out dynamics simulation studies, aiming at validating the implemented models of both the transformer as well as the other grid components. Phase-neutral voltages’ deviations are limited, proving......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...... this problem, distribution transformers with on-load tapping capability are under development. This paper presents model and experimental validation of a 35 kVA three-phase power distribution transformer with independent on-load tap changer control capability on each phase. With the purpose of investigating...

  5. 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.

  6. Metastable phase transitions in Mo-Si and V-Si systems activated by high energy ball milling

    Institute of Scientific and Technical Information of China (English)

    柳林

    2002-01-01

    Mechanical alloying of Mo-Si (Mo33Si67) and V-Si (V75Si25) powder mixtures was activated by high energy ball milling at ambient temperature. The metastable phase transitions in both systems during milling were investigated by X-ray diffraction, scanning and transmission electron microscopy. It is found that the alloying processes are closely related to the milling conditions. As far as the Mo-Si system is concerned, ball milling leads to the formation of both α-MoSi2 (room temperature phase) and β-MoSi2 (high temperature phase), but lower energy milling favors the formation of β phase, while higher energy milling promotes the formation of α phase. In addition, if the milling energy is high enough, the Mo/Si reaction is governed by a self-propagating high temperature process. On the other hand, two different pathways of phase transition in the V-Si system were also identified depending on the milling intensity, i.e. weak milling leads to amorphous transition, whereas intensive milling causes the formation of V3Si and V5Si3 intermetallic compounds. Finally, the thermodynamics and kinetics related to the different phase transitions in the two systems were discussed.

  7. 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.

  8. 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.

  9. 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...

  10. Phase I Rinal Report: Ultra-Low Background Alpha Activity Counter

    Energy Technology Data Exchange (ETDEWEB)

    Warburton, W.K.

    2005-07-22

    analyzing the preamplifier signals with a digital signal processor we 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/cm{sup 2}/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 cm{sup 2} electrode into 4 square segments, each 625 cm{sup 2} and demonstrating that signal noise on individual channels reduced as expected. Because the Phase II counter with a 1 m{sup 2} segmented anode would require 16 segments plus a segmented guard as well, we also designed low cost signal processing electronics to instrument it in

  11. Phase locked neural activity in the human brainstem predicts preference for musical consonance.

    Science.gov (United States)

    Bones, Oliver; Hopkins, Kathryn; Krishnan, Ananthanarayan; Plack, Christopher J

    2014-05-01

    When musical notes are combined to make a chord, the closeness of fit of the combined spectrum to a single harmonic series (the 'harmonicity' of the chord) predicts the perceived consonance (how pleasant and stable the chord sounds; McDermott, Lehr, & Oxenham, 2010). The distinction between consonance and dissonance is central to Western musical form. Harmonicity is represented in the temporal firing patterns of populations of brainstem neurons. The current study investigates the role of brainstem temporal coding of harmonicity in the perception of consonance. Individual preference for consonant over dissonant chords was measured using a rating scale for pairs of simultaneous notes. In order to investigate the effects of cochlear interactions, notes were presented in two ways: both notes to both ears or each note to different ears. The electrophysiological frequency following response (FFR), reflecting sustained neural activity in the brainstem synchronised to the stimulus, was also measured. When both notes were presented to both ears the perceptual distinction between consonant and dissonant chords was stronger than when the notes were presented to different ears. In the condition in which both notes were presented to the both ears additional low-frequency components, corresponding to difference tones resulting from nonlinear cochlear processing, were observable in the FFR effectively enhancing the neural harmonicity of consonant chords but not dissonant chords. Suppressing the cochlear envelope component of the FFR also suppressed the additional frequency components. This suggests that, in the case of consonant chords, difference tones generated by interactions between notes in the cochlea enhance the perception of consonance. Furthermore, individuals with a greater distinction between consonant and dissonant chords in the FFR to individual harmonics had a stronger preference for consonant over dissonant chords. Overall, the results provide compelling evidence

  12. Activation Energy of the Low-pH-Induced Lamellar to Bicontinuous Cubic Phase Transition in Dioleoylphosphatidylserine/Monoolein.

    Science.gov (United States)

    Oka, Toshihiko; Saiki, Takahiro; Alam, Jahangir Md; Yamazaki, Masahito

    2016-02-09

    Electrostatic interaction is an important factor for phase transitions between lamellar liquid-crystalline (Lα) and inverse bicontinuous cubic (QII) phases. We investigated the effect of temperature on the low-pH-induced Lα to double-diamond cubic (QII(D)) phase transition in dioleoylphosphatidylserine (DOPS)/monoolein (MO) using time-resolved small-angle X-ray scattering with a stopped-flow apparatus. Under all conditions of temperature and pH, the Lα phase was directly transformed into an intermediate inverse hexagonal (HII) phase, and subsequently the HII phase slowly converted to the QII(D) phase. We obtained the rate constants of the initial step (i.e., the Lα to HII phase transition) and of the second step (i.e., the HII to QII(D) phase transition) using the non-negative matrix factorization method. The rate constant of the initial step increased with temperature. By analyzing this result, we obtained the values of its apparent activation energy, Ea (Lα → HII), which did not change with temperature but increased with an increase in pH. In contrast, the rate constant of the second step decreased with temperature at pH 2.6, although it increased with temperature at pH 2.7 and 2.8. These results indicate that the value of Ea (HII → QII(D)) at pH 2.6 increased with temperature, but the values of Ea (HII → QII(D)) at pH 2.7 and 2.8 were constant with temperature. The values of Ea (HII → QII(D)) were smaller than those of Ea (Lα → HII) at the same pH. We analyzed these results using a modified quantitative theory on the activation energy of phase transitions of lipid membranes proposed initially by Squires et al. (Squires, A. M.; Conn, C. E.; Seddon, J. M.; Templer, R. H. Soft Matter 2009, 5, 4773). On the basis of these results, we discuss the mechanism of this phase transition.

  13. 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.

  14. Adsorptive removal of phthalate ester (Di-ethyl phthalate) from aqueous phase by activated carbon: a kinetic study.

    Science.gov (United States)

    Venkata Mohan, S; Shailaja, S; Rama Krishna, M; Sarma, P N

    2007-07-19

    Adsorptive studies were carried out on Di-ethyl phthalate (DEP) removal from aqueous phase onto activated carbon. Batch sorption studies were performed and the results revealed that activated carbon demonstrated ability to adsorb DEP. Influence of varying experimental conditions such as DEP concentration, pH of aqueous solution, and dosage of adsorbent were investigated on the adsorption process. Sorption interaction of DEP onto activated carbon obeyed the pseudo second order rate equation. Experimental data showed good fit with both the Langmuir and Freundlich adsorption isotherm models. DEP sorption was found to be dependent on the aqueous phase pH and the uptake was observed to be greater at acidic pH.

  15. 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.

  16. 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.

  17. Phase- and morphology-controlled synthesis of cobalt sulfide nanocrystals and comparison of their catalytic activities for hydrogen evolution

    Science.gov (United States)

    Pan, Yuan; Liu, Yunqi; Liu, Chenguang

    2015-12-01

    Colalt sulfide nanocrystals (NCs), including dandelion-like Co9S8 and sphere-like Co3S4, have been synthesized via a thermal decomposition approach using cobalt acetylacetonate as the cobalt source, 1-dodecanethiol as the sulfur source and oleic acid or oleylamine as the high boiling organic solvent. It is found that the molar ratio of the Co:S precursor and the species of solvent play an important role in the control of phase and morphology of cobalt sulfide nanostructures. The phase structure and morphology of the as-synthesized nickel sulfide NCs are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscope (SEM), energy dispersive spectrum (EDS) mapping, X-ray photoelectron spectroscopy (XPS) and N2 adsorption-desorption. Then we further compare the electrocatalytic activity and stability of as-synthesized cobalt sulfide NCs for hydrogen evolution reaction (HER). The results show that sphere-like Co3S4 exhibits better electrocatalytic activity than the dandelion-like Co9S8 NCs for HER, which can be attributed to the difference of phase structure and morphology. The sphere-like Co3S4 NCs have large surface area and high electrical conductivity, both are beneficial to enhance the catalytic activity. This study indicates that the crystalline phase structure and morphology of cobalt sulfide NCs are important for designing HER electrocatalysts with high efficiency and good stability.

  18. 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).

  19. 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.

  20. 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

  1. 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

  2. STUDY OF CORRELATION AND SIGNIFICANCE OF BIOCHEMICAL PARAMETERS IN THE ASSESSMENT OF ACTIVE PHASE OF THYROID EYE DISEASE

    Directory of Open Access Journals (Sweden)

    Ashok Kumar P

    2016-08-01

    Full Text Available AIM Role of Interleukin-6 and HS-CRP Levels in the assessment of active thyroid eye disease. MATERIALS & METHODS A prospective observational study of 30 patients from the age group of 20-60 years with thyroid eye disease done at Regional Institute of Ophthalmology. All patients were subjected to detailed history, ocular examination, systemic examination, biochemical analysis and Imaging. Patients are categorised as mild, moderate and severe active disease based on clinical activity score. For the period of two years, patients are followed at regular periodic intervals according to the severity of disease and results were analysed. RESULTS Out of 30 patients studied, majority of the patients were females (60%, and 70% of the patients had bilateral disease. Among 30 patients, 83.33% in hyperthyroid state, 3.33% in Hypothyroid state, 13.33% in Euthyroid state (Table 3. Smoking being important risk factor in 30% among males. 50% of patients presented with mild disease, 30% with moderate disease, 0% with severe disease. IL-6, HS-CRP levels are increased only in patients with severe active disease (Table 6. Remission attained in all patients when treated earlier with steroids. CONCLUSION Identifying disease activity early and aggressive treatment with systemic steroids in active phase of moderate and severe disease has reduced the morbidity associated with disease. Correlation of IL-6, HS-CRP, TFT levels are significantly increased only in patients with active phase of severe thyroid eye disease but not significantly elevated in active phase of moderate disease. Another pitfall is IL-6 is an expensive ELISA based diagnosis. Thus, IL-6 & HS-CRP cannot be routinely used to screen patients with Thyroid eye disease.

  3. Quantifying activation of perfluorocarbon-based phase-change contrast agents using simultaneous acoustic and optical observation.

    Science.gov (United States)

    Li, Sinan; Lin, Shengtao; Cheng, Yi; Matsunaga, Terry O; Eckersley, Robert J; Tang, Meng-Xing

    2015-05-01

    Phase-change contrast agents in the form of nanoscale droplets can be activated into microbubbles by ultrasound, extending the contrast beyond the vasculature. This article describes simultaneous optical and acoustical measurements for quantifying the ultrasound activation of phase-change contrast agents over a range of concentrations. In experiments, decafluorobutane-based nanodroplets of different dilutions were sonicated with a high-pressure activation pulse and two low-pressure interrogation pulses immediately before and after the activation pulse. The differences between the pre- and post-interrogation signals were calculated to quantify the acoustic power scattered by the microbubbles activated over a range of droplet concentrations. Optical observation occurred simultaneously with the acoustic measurement, and the pre- and post-microscopy images were processed to generate an independent quantitative indicator of the activated microbubble concentration. Both optical and acoustic measurements revealed linear relationships to the droplet concentration at a low concentration range <10(8)/mL when measured at body temperature. Further increases in droplet concentration resulted in saturation of the acoustic interrogation signal. Compared with body temperature, room temperature was found to produce much fewer and larger bubbles after ultrasound droplet activation.

  4. 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.

  5. Study of surface activity of piroxicam at the interface of palm oil esters and various aqueous phases.

    Science.gov (United States)

    Abdulkarim, Muthanna Fawzy; Abdullah, Ghassan Zuhair; Chitneni, Mallikarjun; Yam, Mun Fei; Mahdi, Elrashid Saleh; Salman, Ibrahim Muhammad; Ameer, Omar Ziad; Sattar, Munavvar Abdul; Basri, Mahiran; Noor, Azmin Mohd

    2012-04-01

    The surface activity of some non-steroidal anti-inflammatory agents like ibuprofen was investigated extensively. This fact has attracted the researchers to extend this behavior to other agents like piroxicam. Piroxicam molecules are expected to orient at the interface of oil and aqueous phase. The aim of this study was, firstly, to assess the surface and interfacial tension behaviour of newly synthesised palm oil esters and various pH phosphate buffers. Furthermore, the surface and interfacial tension activity of piroxicam was studied. All the measurements of surface and interfacial tension were made using the tensiometer. The study revealed that piroxicam has no effect on surface tension values of all pH phosphate buffers and palm oil esters. Similarly, various concentrations of piroxicam did not affect the interfacial tensions between the oil phase and the buffer phases. Accordingly, the interfacial tension values of all mixtures of oil and phosphate buffers were considerably high which indicates the immiscibility. It could be concluded that piroxicam has no surface activity. Additionally, there is no surface pressure activity of piroxicam at the interface of plam oil esters and phosphate buffers in the presence of Tweens and Spans.

  6. 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.

  7. Induction of phase 2 enzymes by serum oxidized polyamines through activation of Nrf2: effect of the polyamine metabolite acrolein.

    Science.gov (United States)

    Kwak, Mi-Kyoung; Kensler, Thomas W; Casero, Robert A

    2003-06-06

    The naturally occurring polycationic polyamines including putrescine, spermidine, and spermine play an important role in cell growth, differentiation, and gene expression. However, circulating polyamines are potential substrates for several oxidizing enzymes including copper-containing serum amine oxidase. These enzymes are capable of oxidizing serum polyamines to several toxic metabolites including aldehydes and H(2)O(2). In this study, we investigated the effects of polyamines as inducers of phase 2 enzymes and other genes that promote cell survival in a cell culture system in the presence of bovine serum. Spermidine and spermine (50 microM) increased NAD(P)H quinone oxidoreductase (NQO1) activity up to 3-fold in murine keratinocyte PE cells. Transcript levels for glutathione S-transferase (GST) A1, GST M1, NQO1, gamma-glutamylcysteine ligase regulatory subunit, and UDP-glucuronyltransferase 1A6 were significantly increased by spermidine and this effect was mediated through the antioxidant response element (ARE). The ARE from the mouse GST A1 promoter was activated about 9-fold by spermine and 5-fold by spermidine treatment, but could be inhibited by the amine oxidase inhibitor, aminoguanidine, suggesting that acrolein or hydrogen peroxide generated from polyamines by serum amine oxidase may be mediators for phase 2 enzyme induction. Elevations of ARE-luciferase expression and NQO1 enzyme activity by spermidine were not affected by catalase, while both were completely repressed by aldehyde dehydrogenase treatment. Direct addition of acrolein to PE cells induced multiple phase 2 genes and elevated nuclear levels of Nrf2, a transcription factor that binds to the ARE. Expression of mutant Nrf2 repressed the activation of the ARE-luciferase reporter by polyamines and acrolein. These results indicate that spermidine and spermine increase the expression of phase 2 genes in cells grown in culture through activation of the Nrf2-ARE pathway by generating the sulfhydryl

  8. Photocatalytical Antibacterial Activity of Mixed-Phase TiO2 Nanocomposite Thin Films against Aggregatibacter actinomycetemcomitans.

    Science.gov (United States)

    Yeniyol, Sinem; Mutlu, Ilven; He, Zhiming; Yüksel, Behiye; Boylan, Robert Joseph; Ürgen, Mustafa; Karabuda, Zihni Cüneyt; Basegmez, Cansu; Ricci, John Lawrence

    2015-01-01

    Mixed-phase TiO2 nanocomposite thin films consisting of anatase and rutile prepared on commercially pure Ti sheets via the electrochemical anodization and annealing treatments were investigated in terms of their photocatalytic activity for antibacterial use around dental implants. The resulting films were characterized by scanning electron microscopy (SEM), and X-ray diffraction (XRD). The topology was assessed by White Light Optical Profiling (WLOP) in the Vertical Scanning Interferometer (VSI) mode. Representative height descriptive parameters of roughness R a and R z were calculated. The photocatalytic activity of the resulting TiO2 films was evaluated by the photodegradation of Rhodamine B (RhB) dye solution. The antibacterial ability of the photocatalyst was examined by Aggregatibacter actinomycetemcomitans suspensions in a colony-forming assay. XRD showed that anatase/rutile mixed-phase TiO2 thin films were predominantly in anatase and rutile that were 54.6 wt% and 41.9 wt%, respectively. Craters (2-5 µm) and protruding hills (10-50 µm) on Ti substrates were produced after electrochemical anodization with higher R a and R z surface roughness values. Anatase/rutile mixed-phase TiO2 thin films showed 26% photocatalytic decolorization toward RhB dye solution. The number of colonizing bacteria on anatase/rutile mixed-phase TiO2 thin films was decreased significantly in vitro. The photocatalyst was effective against A. actinomycetemcomitans colonization.

  9. Activation of AMPA receptors in the suprachiasmatic nucleus phase-shifts the mouse circadian clock in vivo and in vitro.

    Directory of Open Access Journals (Sweden)

    Yasutaka Mizoro

    Full Text Available The glutamatergic neurotransmission in the suprachiasmatic nucleus (SCN plays a central role in the entrainment of the circadian rhythms to environmental light-dark cycles. Although the glutamatergic effect operating via NMDAR (N-methyl D-aspartate receptor is well elucidated, much less is known about a role of AMPAR (alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor in circadian entrainment. Here we show that, in the mouse SCN, GluR2 and GluR4 AMPAR subtypes are abundantly expressed in the retinorecipient area. In vivo microinjection of AMPA in the SCN during the early subjective night phase-delays the behavioral rhythm. In the organotypic SCN slice culture, AMPA application induces phase-dependent phase-shifts of core-clock gene transcription rhythms. These data demonstrate that activation of AMPAR is capable of phase-shifting the circadian clock both in vivo and in vitro, and are consistent with the hypothesis that activation of AMPA receptors is a critical step in the transmission of photic information to the SCN.

  10. Photocatalytical Antibacterial Activity of Mixed-Phase TiO2 Nanocomposite Thin Films against Aggregatibacter actinomycetemcomitans

    Directory of Open Access Journals (Sweden)

    Sinem Yeniyol

    2015-01-01

    Full Text Available Mixed-phase TiO2 nanocomposite thin films consisting of anatase and rutile prepared on commercially pure Ti sheets via the electrochemical anodization and annealing treatments were investigated in terms of their photocatalytic activity for antibacterial use around dental implants. The resulting films were characterized by scanning electron microscopy (SEM, and X-ray diffraction (XRD. The topology was assessed by White Light Optical Profiling (WLOP in the Vertical Scanning Interferometer (VSI mode. Representative height descriptive parameters of roughness Ra and Rz were calculated. The photocatalytic activity of the resulting TiO2 films was evaluated by the photodegradation of Rhodamine B (RhB dye solution. The antibacterial ability of the photocatalyst was examined by  Aggregatibacter actinomycetemcomitans suspensions in a colony-forming assay. XRD showed that anatase/rutile mixed-phase TiO2 thin films were predominantly in anatase and rutile that were 54.6 wt% and 41.9 wt%, respectively. Craters (2–5 µm and protruding hills (10–50 µm on Ti substrates were produced after electrochemical anodization with higher Ra and Rz surface roughness values. Anatase/rutile mixed-phase TiO2 thin films showed 26% photocatalytic decolorization toward RhB dye solution. The number of colonizing bacteria on anatase/rutile mixed-phase TiO2 thin films was decreased significantly in vitro. The photocatalyst was effective against A. actinomycetemcomitans colonization.

  11. 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.

  12. Active control on high-order coherence and statistic characterization on random phase fluctuation of two classical point sources.

    Science.gov (United States)

    Hong, Peilong; Li, Liming; Liu, Jianji; Zhang, Guoquan

    2016-03-29

    Young's double-slit or two-beam interference is of fundamental importance to understand various interference effects, in which the stationary phase difference between two beams plays the key role in the first-order coherence. Different from the case of first-order coherence, in the high-order optical coherence the statistic behavior of the optical phase will play the key role. In this article, by employing a fundamental interfering configuration with two classical point sources, we showed that the high- order optical coherence between two classical point sources can be actively designed by controlling the statistic behavior of the relative phase difference between two point sources. Synchronous position Nth-order subwavelength interference with an effective wavelength of λ/M was demonstrated, in which λ is the wavelength of point sources and M is an integer not larger than N. Interestingly, we found that the synchronous position Nth-order interference fringe fingerprints the statistic trace of random phase fluctuation of two classical point sources, therefore, it provides an effective way to characterize the statistic properties of phase fluctuation for incoherent light sources.

  13. Phase and Antiphase Synchronization between 3-Cell CNN and Volta Fractional-Order Chaotic Systems via Active Control

    OpenAIRE

    Zahra Yaghoubi; Hassan Zarabadipour

    2012-01-01

    Synchronization of fractional-order chaotic dynamical systems is receiving increasing attention owing to its interesting applications in secure communications of analog and digital signals and cryptographic systems. In this paper, a drive-response synchronization method is studied for “phase and antiphase synchronization” of a class of fractional-order chaotic systems via active control method, using the 3-cell and Volta systems as an example. These examples are used to illustrate the effecti...

  14. 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....

  15. 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.

  16. Evaluation of the prevalence of stress and its phases in acute myocardial infarction in patients active in the labor market

    Directory of Open Access Journals (Sweden)

    Luciane Boreki Lucinda

    2015-02-01

    Full Text Available Introduction: Acute myocardial infarction is a social health problem of epidemiological relevance, with high levels of morbidity and mortality. Stress is one of the modifiable risk factors that triggers acute myocardial infarction. Stress is a result of a set of physiological reactions, which when exaggerated in intensity or duration can lead to imbalances in one's organism, resulting in vulnerability to diseases. Objective: To identify the presence of stress and its phases in hospitalized and active labor market patients with unstable myocardial infarction and observe its correlation with the life of this population with stress. Methods: The methodology used was a quantitative, descriptive and transversal research approach conducted with a total of 43 patients, who were still active in the labor market, presenting or not morbidities. Data collection occurred on the fourth day of their hospitalization and patients responded to Lipp's Stress Symptom Inventory for adults. Results: Thirty-one patients (72.1% presented stress and twelve (27.8% did not. In patients with stress, the identified phases were: alert - one patient (3.2%; resistance -twenty-two patients (71.0%; quasi-exhaustion - six patients (19.4% and exhaustion - two patients (6.5%. All women researched presented stress. Conclusion: The results suggest a high level of stress, especially in the resistance phase, in the male infarcted population, hospitalized and active in the labor market.

  17. 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.

  18. 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

    Continuous hydrolysis of an active pharmaceutical ingredient intermediate, and subsequent liquid–liquid (L-L) separation of the resulting organic and aqueous phases, have been achieved using a simple PTFE tube reactor connected to a miniscale hydrophobic membrane separator. An alkoxide product...... 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...

  19. Design optimization of shape memory alloy active structures using the R-phase transformation

    NARCIS (Netherlands)

    Langelaar, M.; Van Keulen, F.

    2007-01-01

    This article illustrates the opportunities that combining computational modeling and systematic design optimization techniques offer to facilitate the design process of shape memory alloy (SMA) structures. Focus is on shape memory behavior due to the R-phase transformation in Ni-Ti, for which a dedi

  20. Self-organized network of phase oscillators coupled by activity-dependent interactions.

    Science.gov (United States)

    Aoki, Takaaki; Aoyagi, Toshio

    2011-12-01

    We investigate a network of coupled phase oscillators whose interactions evolve dynamically depending on the relative phases between the oscillators. We found that this coevolving dynamical system robustly yields three basic states of collective behavior with their self-organized interactions. The first is the two-cluster state, in which the oscillators are organized into two synchronized groups. The second is the coherent state, in which the oscillators are arranged sequentially in time. The third is the chaotic state, in which the relative phases between oscillators and their coupling weights are chaotically shuffled. Furthermore, we demonstrate that self-assembled multiclusters can be designed by controlling the weight dynamics. Note that the phase patterns of the oscillators and the weighted network of interactions between them are simultaneously organized through this coevolving dynamics. We expect that these results will provide new insight into self-assembly mechanisms by which the collective behavior of a rhythmic system emerges as a result of the dynamics of adaptive interactions.

  1. Identification of new compounds with high activity against stationary phase Borrelia burgdorferi from the NCI compound collection.

    Science.gov (United States)

    Feng, Jie; Shi, Wanliang; Zhang, Shuo; Zhang, Ying

    2015-06-03

    Lyme disease is the leading tick-borne disease in the USA. Whereas the majority of Lyme disease patients with early disease can be cured with standard treatment, some patients suffer from chronic fatigue and joint and muscular pain despite treatment, a syndrome called posttreatment Lyme disease syndrome. Although the cause is unclear, ineffective killing of Borrelia burgdorferi persisters by current Lyme disease antibiotics is one possible explanation. We took advantage of our recently developed high-throughput viability assay and screened the National Cancer Institute compound library collection consisting of 2526 compounds against stationary phase B. burgdorferi. We identified the top 30 new active hits, including the top six anthracycline antibiotics daunomycin 3-oxime, dimethyldaunomycin, daunomycin, NSC299187, NSC363998 and nogalamycin, along with other compounds, including prodigiosin, mitomycin, nanaomycin and dactinomycin, as having excellent activity against B. burgdorferi stationary phase culture. The anthracycline or anthraquinone compounds, which are known to have both anti-cancer and antibacterial activities, also had high activity against growing B. burgdorferi with low minimum inhibitory concentration. Future studies on the structure-activity relationship and mechanisms of action of anthracyclines/anthraquinones are warranted. In addition, drug combination studies with the anthracycline class of compounds and the current Lyme antibiotics to eradicate B. burgdorferi persisters in vitro and in animal models are needed to determine if they improve the treatment of Lyme disease.

  2. 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.

  3. 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.

  4. Inorganic nitrogen assimilation in yeasts: alteration in enzyme activities associated with changes in cultural conditions and growth phase.

    Science.gov (United States)

    Thomulka, K W; Moat, A G

    1972-01-01

    Ammonia assimilation has been investigated in four strains of Saccharomyces cerevisiae by measuring, at intervals throughout the growth cycle, the activities of several enzymes concerned with inorganic ammonia assimilation. Enzyme activities in extracts of cells were compared after growth in complete and defined media. The effect of shift from growth in a complete to growth in a defined medium (and the reverse) was also determined. The absence of aspartase (EC 4.3.1.1, l-aspartate-ammonia lyase) activity, the low specific activities of alanine dehydrogenase, glutamine synthetase [EC 6.3.1.2, l-glutamate-ammonia ligase (ADP)], and the marked increase in activity of the nicotinamide adenine dinucleotide phosphate-linked glutamate dehydrogenase (NADP-GDH) [EC 1.4.1.4, l-glutamate:NADP-oxidoreductase (deaminating)] during the early stages of growth support the conclusion that yeasts assimilate ammonia primarily via glutamate. The NADP-GDH showed a rapid increase in activity just before the initiation of exponential growth, reached a maximum at the mid-exponential stage, and then gradually declined in activity in the stationary phase. The NADP-GDH reached a higher level of activity when the yeasts were grown on the defined medium as compared with complete medium. The nicotinamide adenine dinucleotide-linked glutamate dehydrogenase (NAD-GDH) [EC 1.4.1.2, l-glutamate:NAD-oxidoreductase (deaminating)] showed only slight increases in activity during the exponential phase of growth. There was an inverse relationship in that the NADP-GDH increased in activity as the NAD-GDH decreased. The NAD-GDH activity was higher after growth on the complete medium. The glutamate-oxaloacetate transaminase (EC 2.6.1.1. l-aspartate:2-oxoglutarate aminotransferase) activity rose and fell in parallel with the NADP-GDH, although its specific activity was somewhat lower. Although other ammonia-assimilatory enzymes were demonstrable, it seems unlikely that their combined activities could account

  5. Response of Global Lightning Activity Observed by the TRMM/LIS During Warm and Cold ENSO Phases

    Science.gov (United States)

    Chronis, Themis G.; Cecil, Dan; Goodman, Steven J.; Buechler, Dennis

    2007-01-01

    This paper investigates the response of global lightning activity to the transition from the warm (January February March-JFM 1998) to the cold (JFM 1999) ENSO phase. The nine-year global lightning climatology for these months from the Tropical Rainfall Measuring Mission (TRMM) Lightning Imaging Sensor (LIS) provides the observational baseline. Flash rate density is computed on a 5.0x5.0 degree lat/lon grid within the LIS coverage area (between approx.37.5 N and S) for each three month period. The flash rate density anomalies from this climatology are examined for these months in 1998 and 1999. The observed lightning anomalies spatially match the documented general circulation features that accompany the warm and cold ENSO events. During the warm ENSO phase the dominant positive lightning anomalies are located mostly over the Western Hemisphere and more specifically over Gulf of Mexico, Caribbean and Northern Mid-Atlantic. We further investigate specifically the Northern Mid-Atlantic related anomaly features since these show strong relation to the North Atlantic Oscillation (NAO). Furthermore these observed anomaly patterns show strong spatial agreement with anomalous upper level (200 mb) cold core cyclonic circulations. Positive sea surface temperature anomalies during the warm ENSO phase also affect the lightning activity, but this is mostly observed near coastal environments. Over the open tropical oceans, there is climatologically less lightning and the anomalies are less pronounced. Warm ENSO related anomalies over the Eastern Hemisphere are most prominent over the South China coast. The transition to the cold ENSO phase illustrates the detected lightning anomalies to be more pronounced over East and West Pacific. A comparison of total global lightning between warm and cold ENSO phase reveals no significant difference, although prominent regional anomalies are located over mostly oceanic environments. All three tropical "chimneys" (Maritime Continent, Central

  6. SERPINE2, an inhibitor of plasminogen activators, is highly expressed in the human endometrium during the secretory phase

    Directory of Open Access Journals (Sweden)

    Hwu Yuh-Ming

    2011-03-01

    Full Text Available Abstract Background SERPINE2, also known as protease nexin-1, belongs to the serine protease inhibitor (SERPIN superfamily. It is one of the potent SERPINs that modulates the activity of plasminogen activators (PAs. PAs and their SERPIN inhibitors, such as SERPINB2 and SERPINE1, were expressed in the human endometrium and were implicated in implantation. However, expression data about SERPINE2 in the human endometrium is still unknown. Thus, we conducted an investigation to reveal the spatiotemporal and cellular expression of SERPINE2 in the human uterus during the menstrual cycle. Methods Seven patients who underwent a hysterectomy and samples of 120 archived patients' endometrial curettage or parts of the uterus that were formalin-fixed and embedded in paraffin. Western blotting was performed to evaluate the specificity and sensitivity of the antibody. Immunohistochemistry was conducted to localize the SERPINE2 expression site. Quantitative analysis was conducted to evaluate expression levels of SERPINE2 in various sub-phases of the menstrual cycle. Results The SERPINE2 protein was primarily detected in the uterine fluid during the mid- and late-secretory phases of the menstrual cycle. It was predominantly expressed in the luminal and glandular epithelium, less in the myometrium, and only dispersedly in certain stromal cells throughout the menstrual cycle. A quantitative analysis of expression levels of SERPINE2 in the glandular epithelium revealed that it was highly expressed in the endometrium during the secretory phase compared to the proliferative phase. Conclusions The SERPINE2 protein is highly expressed in the endometrium during the secretory phase, indicating that it may participate in tissue remodeling involved in implantation.

  7. 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.

  8. 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

  9. The Effect of Gender and Menstrual Phase on Serum Creatine Kinase Activity and Muscle Soreness Following Downhill Running

    Directory of Open Access Journals (Sweden)

    Tanja Oosthuyse

    2017-02-01

    Full Text Available Serum creatine kinase (CK activity reflects muscle membrane disruption. Oestrogen has antioxidant and membrane stabilising properties, yet no study has compared the CK and muscle soreness (DOMS response to unaccustomed exercise between genders when all menstrual phases are represented in women. Fifteen eumenorrhoeic women (early follicular, EF (n = 5; late follicular, LF (n = 5; mid-luteal, ML (n = 5 phase and six men performed 20 min of downhill running (−10% gradient at 9 km/h. Serum CK activity and visual analogue scale rating of perceived muscle soreness were measured before, immediately, 24-h, 48-h and 72-h after exercise. The 24-h peak CK response (relative to pre-exercise was similar between women and men (mean change (95% confidence interval: 58.5 (25.2 to 91.7 IU/L; 68.8 (31.3 to 106.3 IU/L, respectively. However, serum CK activity was restored to pre-exercise levels quicker in women (regardless of menstrual phase than men; after 48-h post exercise in women (16.3 (−4.4 to 37.0 IU/L; 56.3 (37.0 to 75.6 IU/L, respectively but only after 72-h in men (14.9 (−14.8 to 44.6 IU/L. Parallel to the CK response, muscle soreness recovered by 72-h in men. Conversely, the women still reported muscle soreness at 72-h despite CK levels being restored by 48-h; delayed recovery of muscle soreness appeared mainly in EF and LF. The CK and DOMS response to downhill running is gender-specific. The CK response recovers quicker in women than men. The CK and DOMS response occur in concert in men but not in women. The DOMS response in women is prolonged and may be influenced by menstrual phase.

  10. The Effect of Gender and Menstrual Phase on Serum Creatine Kinase Activity and Muscle Soreness Following Downhill Running.

    Science.gov (United States)

    Oosthuyse, Tanja; Bosch, Andrew N

    2017-02-23

    Serum creatine kinase (CK) activity reflects muscle membrane disruption. Oestrogen has antioxidant and membrane stabilising properties, yet no study has compared the CK and muscle soreness (DOMS) response to unaccustomed exercise between genders when all menstrual phases are represented in women. Fifteen eumenorrhoeic women (early follicular, EF (n = 5); late follicular, LF (n = 5); mid-luteal, ML (n = 5) phase) and six men performed 20 min of downhill running (-10% gradient) at 9 km/h. Serum CK activity and visual analogue scale rating of perceived muscle soreness were measured before, immediately, 24-h, 48-h and 72-h after exercise. The 24-h peak CK response (relative to pre-exercise) was similar between women and men (mean change (95% confidence interval): 58.5 (25.2 to 91.7) IU/L; 68.8 (31.3 to 106.3) IU/L, respectively). However, serum CK activity was restored to pre-exercise levels quicker in women (regardless of menstrual phase) than men; after 48-h post exercise in women (16.3 (-4.4 to 37.0) IU/L; 56.3 (37.0 to 75.6) IU/L, respectively) but only after 72-h in men (14.9 (-14.8 to 44.6) IU/L). Parallel to the CK response, muscle soreness recovered by 72-h in men. Conversely, the women still reported muscle soreness at 72-h despite CK levels being restored by 48-h; delayed recovery of muscle soreness appeared mainly in EF and LF. The CK and DOMS response to downhill running is gender-specific. The CK response recovers quicker in women than men. The CK and DOMS response occur in concert in men but not in women. The DOMS response in women is prolonged and may be influenced by menstrual phase.

  11. ANN based controller for three phase four leg shunt active filter for power quality improvement

    Directory of Open Access Journals (Sweden)

    J. Jayachandran

    2016-03-01

    Full Text Available In this paper, an artificial neural network (ANN based one cycle control (OCC strategy is proposed for the DSTATCOM shunted across the load in three phase four wire distribution system. The proposed control strategy mitigates harmonic/reactive currents, ensures balanced and sinusoidal source current from the supply mains that are nearly in phase with the supply voltage and compensates neutral current under varying source and load conditions. The proposed control strategy is superior over conventional methods as it eliminates, the sensors needed for sensing load current and coupling inductor current, in addition to the multipliers and the calculation of reference currents. ANN controllers are implemented to maintain voltage across the capacitor and as a compensator to compensate neutral current. The DSTATCOM performance is validated for all possible conditions of source and load by simulation using MATLAB software and simulation results prove the efficacy of the proposed control over conventional control strategy.

  12. 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

    of this filter is easily done, for a wide range of sampling frequencies, with the use of genetic algorithms. This method is used only for the optimum choice of the parameters in the filter, and an on-line implementation is not needed. Thus the resulting active damping solution does not need new sensors...

  13. Enhanced Photocatalytic Activity of Bismuth Precursor by Rapid Phase and Surface Transformation Using Structure-Guided Combustion Waves.

    Science.gov (United States)

    Lee, Kang Yeol; Hwang, Hayoung; Kim, Tae Ho; Choi, Wonjoon

    2016-02-10

    The development of an efficient method for manipulating phase and surface transformations would facilitate the improvement of catalytic materials for use in a diverse range of applications. Herein, we present the first instance of a submicrosecond time frame direct phase and surface transformation of Bi(NO3)3 rods to nanoporous β-Bi2O3 rods via structure-guided combustion waves. Hybrid composites of the prepared Bi(NO3)3·H2O rods and organic fuel were fabricated by a facile preparation method. The anisotropic propagation of combustion waves along the interfacial boundaries of Bi(NO3)3·H2O rods induced direct phase transformation to β-Bi2O3 rods in the original structure due to the rapid pyrolysis, while the release of gas molecules enabled the formation of nanoporous structures on the surfaces of rods. The developed β-Bi2O3 rods showed improved photocatalytic activity for the photodegradation of rhodamine B in comparison with Bi(NO3)3·H2O rods and α-Bi2O3 rods due to the more suitable interdistance and the large contact areas of the porous surfaces. This new method of using structure-guided combustion waves for phase and surface transformation may contribute to the development of new catalysts as well as the precise manipulation of diverse micronanostructured materials.

  14. Design and Analysis of Phase Change Material based thermal energy storage for active building cooling: a Review

    Directory of Open Access Journals (Sweden)

    Nitin .D. Patil

    2012-06-01

    Full Text Available Phase Change Materials (PCMs are "latent" thermal storage materials. They use chemical bonds to store and release heat. The thermal energy transfer occurs when a material changes from a solid to a liquid orfrom a liquid to a solid form. This is called a change in state or "phase." Initially, these solid-liquid PCMs perform like conventional storage materials; their temperature rises as they absorb solar heat. Unlike conventional heat storage materials, when PCMs reach the temperature at which they change phase (their melting point, they absorb large amounts of heat without getting hotter. When the ambient temperature in the space around the PCM material drops, the Phase Change Material solidifies, releasing its stored latent heat. PCMs absorb and emit heat while maintaining a nearly constant temperature. Within the human comfort and electronic-equipment tolerance range of 20°C to 35°C, latent thermal storage materials are very effective.They can be used for equalization of day & night temperature and for transport of refrigerated products. In the proposed project heat of fusion of Cacl2. 6H2o as PCM is used for cooling water during night and this cooled water is used as circulating medium trough fan coil unit, air trough FCU will get cooled by transferring heat to water and fresh & cool air will be thrown in a room. In the proposed project FREE COOLING & ACTIVE BUILDING COOLING concepts of Thermal Energy Storage are used in combine

  15. Adsorption-Driven Catalytic and Photocatalytic Activity of Phase Tuned In2S3 Nanocrystals Synthesized via Ionic Liquids.

    Science.gov (United States)

    Sharma, Rahul Kumar; Chouryal, Yogendra Nath; Chaudhari, Sushmita; Saravanakumar, Jeganathan; Dey, Suhash Ranjan; Ghosh, Pushpal

    2017-03-14

    Phase tuned quantum confined In2S3 nanocrystals are accessible solvothermally using task-specific ionic liquids (ILs) as structure directing agents. Selective tuning of size, shape, morphology and, most importantly, crystal phase of In2S3 is achieved by changing the alkyl side chain length, the H-bonding and aromatic -stacking ability of the 1-alkyl-3- methylimidazolium bromide ILs, [Cnmim]Br (n=2,4,6,8 and 10). It is observed that crystallite size is significantly less when ILs are used compared to the synthesis without ILs keeping the other reaction parameters same. At 150oC, when no IL is used, pure tetragonal form of -In2S3 appears however in presence of [Cnmim]Br [n=2,4], at the same reaction condition, a pure cubic phase crystallizes. However in case of methylimidazolium bromides with longer pendant alkyl chains such as hexyl (C6), octyl (C8) or decyl (C10), nanoparticles of the tetragonal polymorph form. Likewise, judicious choice of reaction temperature and precursors has a profound effect to obtain phase pure and morphology controlled nanocrystals. Furthermore, the adsorption driven catalytic and photocatalytic activity of as-prepared nanosized indium sulphide is confirmed by studying the degradation of crystal violet (CV) dye in presence of dark and visible light. Maximum 94.8 % catalytic efficiency is obtained for the In2S3 nanocrystals using tetramethylammonium bromide (TMAB) ionic liquid.

  16. Preparation of electrospun Ag/TiO2 nanotubes with enhanced photocatalytic activity based on water/oil phase separation

    Science.gov (United States)

    Wang, Tao; Wei, Jinxin; Shi, Huimin; Zhou, Ming; Zhang, Yu; Chen, Qi; Zhang, Zhengmei

    2017-02-01

    Ag/TiO2 composite nanotubes were prepared by electrospinning based on water/oil phase separation effect, their photocatalytic abilities were evaluated under the UV-visible light irradiation. Comparing with bare TiO2 nanofibers, Ag/TiO2 nanotubes exhibited enhanced photocatalytic activities in the decomposition of Rhodamine B (RhB) solution. The enhanced photocatalytic activity of Ag/TiO2 nanotubes stems from the improved separation of photo-generated electron-hole pairs induced by Ag and the high dyes absorption ability of Ag/TiO2 nanotubes; the high specific surface areas of Ag/TiO2 nanotubes with large amounts of active sites, speeding the photocatalytic activity up; the short diffusion path of photo-generated carriers caused by thin thickness of Ag/TiO2 nanotubes. The strategy, fabrication electrospun Ag/TiO2 hybrid nanotubes based on water/oil phase separation effect, is a one step, simple and versatile method, which can be easily expanded to the fabrication of other materials for photocatalysis, water splitting and energy conversion.

  17. 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.

  18. 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.

  19. Neuromagnetic abnormality of motor cortical activation and phases of headache attacks in childhood migraine.

    Directory of Open Access Journals (Sweden)

    Jing Xiang

    Full Text Available The cerebral cortex serves a primary role in the pathogenesis of migraine. This aberrant brain activation in migraine can be noninvasively detected with magnetoencephalography (MEG. The objective of this study was to investigate the differences in motor cortical activation between attacks (ictal and pain free intervals (interictal in children and adolescents with migraine using both low- and high-frequency neuromagnetic signals. Thirty subjects with an acute migraine and 30 subjects with a history of migraine, while pain free, were compared to age- and gender-matched controls using MEG. Motor cortical activation was elicited by a standardized, validated finger-tapping task. Low-frequency brain activation (1~50 Hz was analyzed with waveform measurements and high-frequency oscillations (65-150 Hz were analyzed with wavelet-based beamforming. MEG waveforms showed that the ictal latency of low-frequency brain activation was significantly delayed as compared with controls, while the interictal latency of brain activation was similar to that of controls. The ictal amplitude of low-frequency brain activation was significantly increased as compared with controls, while the interictal amplitude of brain activation was similar to that of controls. The ictal source power of high-frequency oscillations was significantly stronger than that of the controls, while the interictal source power of high-frequency oscillations was significantly weaker than that of controls. The results suggest that aberrant low-frequency brain activation in migraine during a headache attack returned to normal interictally. However, high-frequency oscillations changed from ictal hyper-activation to interictal hypo-activation. Noninvasive assessment of cortical abnormality in migraine with MEG opens a new window for developing novel therapeutic strategies for childhood migraine by maintaining a balanced cortical excitability.

  20. Enhancement of Lipase Enzyme Activity in Non-Aqueous Media through a Rapid Three Phase Partitioning and Microwave Irradiation

    Directory of Open Access Journals (Sweden)

    N. Saifuddin

    2008-01-01

    Full Text Available Three phase partitioning is fast developing as a novel bio-separation strategy with a wide range of applications including enzyme stability and enhancement of its catalytic activity. pH tuning of enzyme is now well known for use in non-aqueous systems. Tuned enzyme was prepared using a rapid drying technique of microwave dehydration (time required around 15 minutes. Further enhancement was achieved by three phase partitioning (TPP method. With optimal condition of ammonium sulphate and t-butanol, the protein appeared as an interfacial precipitate between upper t-butanol and lower aqueous phases. In this study we report the results on the lipase which has been subjected to pH tuning and TPP, which clearly indicate the remarkable increase in the initial rate of transesterification by 3.8 times. Microwave irradiation was found to increase the initial reaction rates by further 1.6 times, hence giving a combined increase in activity of about 5.4 times. Hence it is shown that microwave irradiation can be used in conjunction with other strategies (like pH tuning and TPP for enhancing initial reaction rates.

  1. 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 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...... 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...... 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...

  2. Research on the filtering characteristic of single phase series hybrid active power filter based on fundamental magnetic flux compensation

    Science.gov (United States)

    Tian, Jun; Chen, Qiaofu; Zhang, Yuqi

    2012-12-01

    In this article, the PWM inverter works as a controlled fundamental current source in the single phase series hybrid active power filter (APF) based on fundamental magnetic flux compensation (FMFC). The series transformer can exhibit the self-impedance of primary winding to harmonic current, which forces harmonic current to flow into passive power filter. With the influence of harmonic current, the voltage of primary winding of transformer is a harmonic voltage, which makes the inverter output currents have a certain harmonic component, and it degrades the filtering characteristics. On the basis of PWM inverter, the mathematical model of series hybrid APF is established, and the filtering characteristics of single phase APF are analysed in detail. Three methods are gained to improve filtering characteristics: reasonably designing the inverter output filter inductance, increasing series transformer ratio and adopting voltage feed-forward control. Experimental results show that the proposed APF has greater validity.

  3. DPC controlled three-phase active filter for power quality improvement

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-10-15

    This paper presents a new control method entitled direct power control (DPC) for shunt active power filtering (5th, 7th, 11th,..) (SAPF), which is applied to eliminate line current harmonics and compensate reactive power. Its main goal is to rebuild active and reactive powers to be compared to references values using hysteresis control. 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 control technique. (author)

  4. 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

    . 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...... are presented to verify the effectiveness of the proposed modeling and control method....

  5. A Generic Topology Derivation Method for Single-phase Converters with Active Capacitive DC-links

    DEFF Research Database (Denmark)

    Wang, Haoran; Wang, Huai; Zhu, Guorong;

    2016-01-01

    capacitive DCDC- link solutions, but important aspects of the topology assess-ment, such as the total energy storage, overall capacitive energy buffer ratio, cost, and reliability are still not available. This paper proposes a generic topology derivation method of single-phase power converters...... with capacitive DC-links, which derives all existing topologies to our best knowledge, and identify a few new topologies. A reliability-oriented design process is applied to compare the cost of different solutions with the lifetime target of 10 years and 35 years, respectively. It reveals that the most cost...

  6. 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.

  7. 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)

  8. PHASE ANALYSIS AS A TOOL OF PREESTIMATED ANALYSIS OF THE ACTIVITY OF A MULTIFUNCTIONAL CENTER

    Directory of Open Access Journals (Sweden)

    Kovaleva K. A.

    2015-03-01

    Full Text Available The article is devoted to the phase analysis as a tool preprocessor analysis of a multi-purpose center. Consider the time series of the daily number of requests received on the basis of the phase portraits of these time series. These time series have strong properties of cycles and periodicity. Practice has shown that in modern conditions, for example, for the Russian economy with its instability and financial crises, classical economic theory and statistics, built on linear models, turned out to be unproductive. Overview of approaches and economic-mathematical methods preprocessor analysis of evolutionary economic processes and the corresponding time series allows concluding the following: one versatile, satisfying all the requirements, do not possess the shortcomings of the method of analysis and forecasting does not exist. Each approach and each method has its advantages, disadvantages, limits of use. Most of the known methods of forecasting operate detected in the considered time series properties of cycles and periodicity. Thus, the mere presence of a pronounced cyclicity at different levels of the considered hierarchical model of the time series of the number of requests in a multi-purpose center are important indicators of the possibility of constructing an adequate predictive model number of requests in the multi-purpose centre

  9. 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.

  10. 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.

  11. Gas-phase formaldehyde adsorption isotherm studies on activated carbon: correlations of adsorption capacity to surface functional group density.

    Science.gov (United States)

    Carter, Ellison M; Katz, Lynn E; Speitel, Gerald E; Ramirez, David

    2011-08-01

    Formaldehyde (HCHO) adsorption isotherms were developed for the first time on three activated carbons representing one activated carbon fiber (ACF) cloth, one all-purpose granular activated carbon (GAC), and one GAC commercially promoted for gas-phase HCHO removal. The three activated carbons were evaluated for HCHO removal in the low-ppm(v) range and for water vapor adsorption from relative pressures of 0.1-0.9 at 26 °C where, according to the IUPAC isotherm classification system, the adsorption isotherms observed exhibited Type V behavior. A Type V adsorption isotherm model recently proposed by Qi and LeVan (Q-L) was selected to model the observed adsorption behavior because it reduces to a finite, nonzero limit at low partial pressures and it describes the entire range of adsorption considered in this study. The Q-L model was applied to a polar organic adsorbate to fit HCHO adsorption isotherms for the three activated carbons. The physical and chemical characteristics of the activated carbon surfaces were characterized using nitrogen adsorption isotherms, X-ray photoelectron spectroscopy (XPS), and Boehm titrations. At low concentrations, HCHO adsorption capacity was most strongly related to the density of basic surface functional groups (SFGs), while water vapor adsorption was most strongly influenced by the density of acidic SFGs.

  12. Control strategy for three-phase four-wire PWM converter of integrated voltage compensation type active SFCL

    Science.gov (United States)

    Chen, Lei; Tang, Yuejin; Shi, Jing; Li, Zhi; Ren, Li; Cheng, Shijie

    2010-02-01

    The integrated voltage compensation type active superconducting fault current limiter (SFCL) is composed of three air-core superconducting transformers and a three-phase four-wire PWM converter. In order to realize the current-limiting characteristics of the integrated active SFCL, it is needed to control the three-phase four-wire PWM converter flexibly and reasonably. Thereby, the control strategy for the converter is analyzed in this paper. In dq0 reference frame, the mathematical model of the converter is founded. The double-loop control strategy, consisting of voltage outer loop and current inner loop, is presented. Moreover, the voltage balance control for the split DC link capacitors is also considered. Using MATLAB, the simulation model of the integrated active SFCL is built. According to the simulation results, it is known that, the presented control strategy is feasible and valid, and the converter can work well under unsymmetrical and symmetrical fault conditions, and then the fault current can be limited quickly and effectively.

  13. 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.

  14. 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

    2008-03-01

    Full Text Available Slightly soluble atmospherically relevant organic compounds, such as adipic acid, may influence particle CCN activity and therefore cloud formation. 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 and dry adipic acid particles without the need to produce them by atomization of aqueous solutions. The CCN effect of adipic acid coatings on both soluble and insoluble particles has also been studied. 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. Adipic acid particles prepared in a wet state follow the Köhler curve over the full range of particle diameters studied. 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 addition of a hydrophilic soluble compound to dry adipic acid eliminates the effect of particle phase, that is, the effect of the deliquescence barrier to CCN activation. An adipic acid coating on hydrophobic soot yields a CCN active particle. For the relatively small soot particles (dcore=88 and 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.

  15. 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.

  16. 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.

  17. Lifetime Estimation of DC-link Capacitors in a Single-phase Converter with an Integrated Active Power Decoupling Module

    DEFF Research Database (Denmark)

    Ma, Siyuan; Wang, Haoran; Tang, Junchaojie;

    2016-01-01

    -link capacitor capacitance can be decreased. However, few research is about the effect of DC side and AC side decoupling on the DC-link capacitor reliability considering its electro-thermal stresses. This paper presents a quantitative analysis on the lifetime of capacitors with power decoupling circuits......In single-phase inverters, DC-link capacitors are installed at the DC-link to buffer the ripple power between the AC side and DC side. Active decoupling methods introduce additional circuits at the DC side or AC side to partially or fully supply the ripple power. So that the demanded DC...

  18. The Effect of Intravenous Fentanyl on Pain and Duration of the Active Phase of First Stage Labor

    OpenAIRE

    Nahid Jahani Shoorab; Samira Ebrahimzadeh Zagami; Kobra Mirzakhani; Seyed Reza Mazlom

    2013-01-01

    Objectives: Opioids are most widely used for pain relief during childbirth. An alternative opioid, fentanyl, has been shown to be a good option for pain management and has fewer side-effects on both mother and fetus. Therefore, the purpose of this study is to determine the effect of fentanyl on pain as well as the duration of the active phase of labor.Methods: This clinical trial was conducted on 70 multiparous parturients having labor from May to July 2006 at Tamin Ejtemai Hospital. They wer...

  19. Phase and Antiphase Synchronization between 3-Cell CNN and Volta Fractional-Order Chaotic Systems via Active Control

    Directory of Open Access Journals (Sweden)

    Zahra Yaghoubi

    2012-01-01

    Full Text Available Synchronization of fractional-order chaotic dynamical systems is receiving increasing attention owing to its interesting applications in secure communications of analog and digital signals and cryptographic systems. In this paper, a drive-response synchronization method is studied for “phase and antiphase synchronization” of a class of fractional-order chaotic systems via active control method, using the 3-cell and Volta systems as an example. These examples are used to illustrate the effectiveness of the synchronization method.

  20. Aerosol-phase Activity of Iodine Captured from a Triiodide Resin Filter on Fine Particles Containing an Infectious Virus

    Science.gov (United States)

    2015-01-01

    AFCEC-CX-TY-TP-2014-0019 AEROSOL-PHASE ACTIVITY OF IODINE CAPTURED FROM A TRIIODIDE RESIN FILTER ON FINE PARTICLES CONTAINING AN INFECTIOUS VIRUS ... Virus (POSTPRINT) FA4819-11-C-0003 X13SY002 X0E7 (QL102007) D.A. Harnish,** B.K. Heimbuch,** C. Balzli,* A. Lumley,** K. Kinney,** E. Rudico,# and J.D...from a triiodide resin filter on fine particles containing an infectious virus B.K. Heimbuch1, D.A. Harnish1, C. Balzli2,*, A. Lumley1, K. Kinney1 and

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

    Science.gov (United States)

    Kim, Yongdae; Kim, Sangyoo; Park, Kyihwan

    2009-04-01

    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.

  2. 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.

  3. 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.

  4. 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.

  5. The influence of phase II conjugation on the biological activity of flavonoids

    NARCIS (Netherlands)

    Beekmann, K.

    2016-01-01

    Flavonoid consumption is often correlated with a wide range of health effects, such as the prevention of cardiovascular diseases, neurodegenerative diseases, and diabetes. These effects are usually ascribed to the activity of the parent flavonoid aglycones, even though these forms of the flavonoids

  6. Solid-phase synthesis and biological activity of a thioether analogue of conotoxin G1

    DEFF Research Database (Denmark)

    Bondebjerg, Jon; Grunnet, Morten; Jespersen, Thomas;

    2003-01-01

    of two isomers, which were evaluated for their ability to inhibit the muscular nicotinic acetylcholine receptor expressed in Xenopus oocytes. The two isomers were found to have IC(50) values (inhibitory activities) of 144 microM and 48 microM, compared to 0.18 microM for native conotoxin G1....

  7. 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

    BACKGROUND: Disturbances of coagulation and fibrinolysis are well-known systemic effects of acute necrotising pancreatitis (ANP). The purpose of this experimental study was to evaluate the initial events in the haemostatic activation during ANP in an animal model with relevance to the human...

  8. 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…

  9. 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

  10. Late Holocene phases of dome growth and Plinian activity at Guagua Pichincha volcano (Ecuador)

    NARCIS (Netherlands)

    Robin, Claude; Samaniego, Pablo; Le Pennec, Jean-Luc; Mothes, Patricia; van der Plicht, Johannes

    2008-01-01

    Since the eruption which affected Quito in AD 1660, Guagua Pichincha has been considered a hazardous volcano. Based on field studies and twenty C-14 dates, this paper discusses the eruptive activity of this volcano, especially that of the last 2000 years. Three major Plinian eruptions with substanti

  11. In vitro biomonitoring in polar extracts of solid phase matrices reveals the presence of unknown compounds with estrogenic activity.

    Science.gov (United States)

    Legler, J; Leonards, P; Spenkelink, A; Murk, A J

    2003-01-01

    Determination of estrogenic activity has so far mainly concentrated on the assessment of compounds in surface water and effluent. This study is one of the first to biomonitor (xeno-)estrogens in sediment, suspended particulate matter and aquatic organisms. The relatively polar acetone extracts from these solid phase matrices do not contain the well-known estrogenic compounds such as hormones, alkylphenols and phthalates. An in vitro 'estrogen receptor-mediated chemical activated luciferase gene expression' (ER-CALUX) assay was applied to samples from various locations in the Netherlands. Estrogenic activity measured in polar fractions of particulate matter and sediment extracts ranged from below detection limit to up to 4.5 pmol estradiol equivalents (EEQ)/g dry weight. Estrogenic activity in freshwater river sediments was up to five times higher compared to sediments from large lakes and coastal locations. Tissue extracts EEQs were determined in bream (Abramis brama), flounder (Platichthysflesus), freshwater mussels (Dreissena polymorpha) and marine mussels (Mytilus edulis). The highest biota EEQ levels were found in the freshwater zebra mussel (30 pmol EEQ/g lipid). One sample site showed greatly elevated EEQs in sediment and biota, which correlated with effects found in the wild populations of bream. The EEQ activity of the unknown compounds in the polar fraction mostly was much higher than the calculated EEQ levels based on known estrogens in the non-polar fraction (previously published data).

  12. Swing Phase Control of Semi-Active Prosthetic Knee Using Neural Network Predictive Control With Particle Swarm Optimization.

    Science.gov (United States)

    Ekkachai, Kittipong; Nilkhamhang, Itthisek

    2016-11-01

    In recent years, intelligent prosthetic knees have been developed that enable amputees to walk as normally as possible when compared to healthy subjects. Although semi-active prosthetic knees utilizing magnetorheological (MR) dampers offer several advantages, they lack the ability to generate active force that is required during some states of a normal gait cycle. This prevents semi-active knees from achieving the same level of performance as active devices. In this work, a new control algorithm for a semi-active prosthetic knee during the swing phase is proposed to reduce this gap. The controller uses neural network predictive control and particle swarm optimization to calculate suitable command signals. Simulation results using a double pendulum model show that the generated knee trajectory of the proposed controller is more similar to the normal gait than previous open-loop controllers at various ambulation speeds. Moreover, the investigation shows that the algorithm can be calculated in real time by an embedded system, allowing for easy implementation on real prosthetic knees.

  13. Multiwavelength temporal variability of the blazar 3C 454.3 during 2014 activity phase

    Science.gov (United States)

    Kushwaha, Pankaj; Gupta, Alok C.; Misra, Ranjeev; Singh, K. P.

    2017-01-01

    We present a multiwavelength temporal analysis of the blazar 3C 454.3 during the high γ-ray active period from May to December, 2014. Except for X-rays, the period is well sampled at near-infrared (NIR)-optical by the Small and Moderate Aperture Research Telescope System (SMARTS) facility, and the source is detected continuously on daily time-scale in the Fermi-Large Area Telescope γ-ray band. The source exhibits diverse levels of variability with many flaring/active states in the continuously sampled γ-ray light curve which are also reflected in the NIR-optical light curves and the sparsely sampled X-ray light curve by the Swift-XRT. Multiband correlation analysis of this continuous segment during different activity periods shows a change of state from no lags between IR and γ-ray, optical and γ-ray, and IR and optical to a state where γ-ray lags the IR/optical by ˜3 d. The results are consistent with the previous studies of the same during various γ-ray flaring and active episodes of the source. This consistency, in turn, suggests an extended localized emission region with almost similar conditions during various γ-ray activity states. On the other hand, the delay of γ-ray with respect to IR/optical and a trend similar to IR/optical in X-rays along with strong broad-band correlations favour magnetic field related origin with X-ray and γ-ray being inverse Comptonization of IR/optical photons and external radiation field, respectively.

  14. 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

  15. 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...... factor correction for an active rectifier in comparison to a passive rectifier. The SiC based power switches thereby offer the possibility of using high switching frequencies leading to a reduction in filter size - here a simple L filter. The controller is able to validate the simulation results...... 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...

  16. [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.

  17. Analysis of active damping of LCL filter used in single-phase PV system in discrete domain

    Science.gov (United States)

    Zhang, Ningyun; Tang, Houjun; Yao, Chen

    2015-06-01

    Sampling and computational delay are necessary in digital control, though they may alter the characteristics of the actual controlled plant when considered in the discrete domain. Accordingly, this article establishes a mathematical model of a single-phase grid-connected inverter with an LCL filter in the discrete domain. Three active damping control delay times: 0, ?, ? are analysed, considering the influences introduced by digital control of the plant. Further, the range of the capacitor current feedback coefficient used in active damping control is derived to guarantee that the controlled plant does not have poles outside the unit circle. Using Nyquist diagrams, the proper proportional-resonant (PR) controller parameters can be intuitively determined. The theoretical analysis is verified using MATLAB and a 3 kW laboratory prototype based on a digital signal processor (TMS320F2808).

  18. 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

    ) 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......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...... 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...

  19. 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

    in the biofilm. Based on the rRNA content, the in situ activity was estimated to be reduced to 20% of cells grown at maximum conditions in batch culture. The toluene degraded by P. putida was estimated to be a minor part (11%) of the overall toluene degradation. (C) 1997 John Wiley & Sons, Inc.......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...... the increase of active biomass and polymers was linear. In order to investigate the toluene degradation, various toluene degraders from the multispecies biofilm were isolated, and a Pseudomonas putida was chosen as a representative of the toluene-degrading population. A specific rRNA oligonucleotide probe...

  20. 腰果酚二醚曼尼希碱固化剂的合成及其相分离现象研究%Synthesis and Phase Separation Phenomena of Cardanol Diethers-Mannich Base Curing Agent

    Institute of Scientific and Technical Information of China (English)

    宋健; 李梅; 李守海; 黄坤; 夏建陵

    2016-01-01

    The cardanol diethers (CDE) was obtained from Williamson etherification of cardanol(CD) and 1,3-dibromopropane.Then the cardanol diethers-Mannich baseas curing agent (MBCDE) for epoxy resins was prepared from the Mannich reaction of CDE, paraformadehyde and diethylenetriamine.The chemical structure was confirmed by FT-IR and 1H NMR.N-Aminoethylpiperazine (AEP) was chose as a control to investigate the toughening properties of MBCDE.Thermogravimetric analysis (TGA), scanning electronic microscopy (SEM) and mechanical properties of the cured epoxies were also conducted to investigate the properties of the bisphenol A epoxy resin (DGEBA) cured by two curing agents.The TGA results showed that the maximum decomposition temperature of MBCDE was 351.6 ℃ and the sample had good thermal stability.The impact strength of cured AEP/DGEBA was 3.641 J/m, while the cured 80% MBCDE sample had an impact strength of 5.155 J/m, which was improved by 41.6%.SEM results indicated that there was phase seperation in the cured materials contained MBCDE.%腰果酚(CD)和1,3-二溴丙烷经Williamson醚化反应得到一种腰果酚二醚化合物(CDE),然后以CDE、多聚甲醛和二乙烯三胺为原料,经Mannich反应制备得到一种浅色的腰果酚二醚曼尼希碱固化剂(MBCDE).通过傅里叶红外光谱(FT-IR)和核磁共振氢谱(1H NMR)表征了产物的化学结构,并与氨乙基哌嗪(AEP)进行对比研究其相关性能.通过热重分析(TGA)、扫描电镜(SEM)和力学性能测试研究了两种固化剂与双酚A环氧树脂(DGEBA)固化材料的相关性能.结果表明:MBCDE/DGEBA的最大分解温度为351.6 ℃,具有良好的热稳定性.AEP/DGEBA环氧固化物的冲击强度为3.641 J/m,而添加80%的MBCDE后固化物的冲击强度则为5.155 J/m,提高了41.6%.SEM分析结果表明MBCDE固化材料中存在相分离.

  1. 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

  2. Memory effect of activated Mg-Al hydrotalcite: in situ XRD studies during decomposition and gas-phase reconstruction.

    Science.gov (United States)

    Pérez-Ramírez, Javier; Abelló, Sònia; van der Pers, Niek M

    2007-01-01

    The thermal decomposition of Mg-Al hydrotalcite and the subsequent reconstruction of the decomposed products in the presence of water vapor (2 vol. % H(2)O in N(2)) have been investigated by in situ XRD. Thermographic analysis and temperature-programmed desorption MS results complemented the diffraction data. Valuable mechanistic and kinetic insights into these processes, which are of prime importance for optimal activation of this type of material for catalytic applications, were obtained. Hydrotalcite decomposition to the mixed oxide proceeds via formation at 423-473 K of an intermediate phase, consisting of a highly disordered, dehydrated, layered structure. The latter evolves by removal of interlayer water on heating, causing a shrinking of the interlayer space (it is up to 45 % smaller than in the as-synthesized hydrotalcite). Above 623 K, Mg(Al)O(x) oxide with the periclase structure is formed. Reversion of the intermediate dehydrated structure to hydrotalcite upon contact with water vapor is complete and very fast at room temperature. Recovery of hydrotalcite from the oxide calcined at 723 K is two orders of magnitude slower than rehydration of the intermediate layered structure and one order of magnitude slower than the typically practiced liquid-phase reconstruction. In contrast to the decomposition, the reconstruction mechanism does not involve an intermediate phase. The gas-phase rehydration and reconstruction was interrupted above 303 K. This is attributed to the poor wetting of the surface of the decomposed materials induced by hampered H(2)O adsorption above room temperature at the water vapor pressure applied. The Avrami-Erofe'ev model describes the reconstruction kinetics well.

  3. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Kerkhoff, Lee; Williams, Kenneth H.; Long, Philip E.; McGuinness, L.

    2011-02-15

    Uranium contaminated groundwaters are a legacy concern for the U.S. Department of Energy. Previous experiments at the Rifle, Colorado Integrated Field Challenge (IFC) site have demonstrated that field-scale addition of acetate to groundwater reduces the ambient soluable uranium concentration, sequestering the radionuclide as uraninite. However, questions remain regarding which microorganism(s) are consuming this acetate and if active groundwater microorganisms are different from active particle-associated bacteria. In this report, 13-C acetate was used to assess the active microbes that synthesize DNA on 3 size fractions [coarse sand, fines (8-approximately 150 micron), groundwater (0.2-8 micron)] over a 24 -day time frame. Results indicated a stronger signal from 13-C acetate associated with the “fines” fraction compared with smaller amounts of 13-C uptake on the sand fraction and groundwater samples during the SIP incubations. TRFLP analysis of this 13-C-labeled DNA, indicated 31+ 9 OTU's with 6 peaks dominating the active profiles (166, 187, 210, 212, and 277 bp peaks using MnlI). Cloning/sequencing of the amplification products indicated a Geobacter-like group (187, 210, 212 bp) primarily synthesized DNA from acetate in the groundwater phase, an alpha Proteobacterium (166 bp) primarily grew on the fines/sands, and an Acinetobacter sp. (277 bp) utilized much of the 13C acetate in both groundwater and particle-associated phases. These findings will help to delineate the acetate utilization patterns of bacteria during field-scale acetate addition and can lead to improved methods for stimulating distinct microbial populations in situ.

  5. Regional Heat Sources and the Active and Break Phases of Boreal Summer Intraseasonal (30-50 Day) Variability(.

    Science.gov (United States)

    Annamalai, H.; Sperber, K. R.

    2005-08-01

    The boreal summer intraseasonal variability (BSISV) associated with the 30-50-day mode is represented by the coexistence 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 outgoing longwave radiation (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 CsEOF mode is significantly tied to the observed spatial rainfall pattern associated with the active/break phases over the Indian subcontinent. The components of the heating patterns from CsEOF analysis serve as prescribed forcings for the dry version of the linear model. This allows one to investigate the possible roles that the regional heat sources and sinks play in driving the large-scale monsoon circulation at various stages of the BSISV life cycle. To understand the interactive nature between convection and circulation, the moist version of the model is forced with intraseasonal SST anomalies.The linear models reproduce the major features of the BSISV seen in the reanalysis. The linear model suggests three new findings: (i) 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 results in low-level convergence and tropospheric moisture enhancement over the equatorial western Indian Ocean and helps trigger the next active phase of the BSISV. (ii) 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, reduces

  6. 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

  7. 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.

  8. 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...... of unaccustomed exercise on global transcriptional profiles in porcine skeletal muscles. Using a combined microarray and candidate gene approach, we identified a suite of genes that are differentially expressed in muscles during postexercise recovery. Several members of the heat shock protein family and proteins...... 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...

  9. Assessment of Phenolic Compounds and Anti-Inflammatory Activity of Ethyl Acetate Phase of Anacardium occidentale L. Bark

    Directory of Open Access Journals (Sweden)

    Marina Suênia de Araújo Vilar

    2016-08-01

    Full Text Available The bark of A. occidentale L. is rich in tannins. Studies have described various biological activities of the plant, including antimicrobial, antioxidant, antiulcerogenic and antiinflammatory actions. The objective of this study was to assess the activity of the ethyl acetate phase (EtOAc of A. occidentale on acute inflammation and to identify and quantify its phenolic compounds by HPLC. The method was validated and shown to be linear, precise and accurate for catechin, epicatechin, epigallocatechin and gallic acid. Swiss albino mice (Mus musculus were treated with saline, Carrageenan (2.5%, Indomethacin (10 mg/kg, Bradykinin (6 nmol and Prostaglandine E2 (5 µg at different concentrations of EtOAc - A. occidentale (12.5; 25; 50; and 100 mg/kg/weight p.o. for the paw edema test. Challenge was performed with carrageenan (500 µg/mL i.p. for the doses 50 and 100 mg/kg of EtOAc. Levels of cytokines IL-1, TNF-α, IL-6 and IL-10 were also measured. All EtOAc - A. occidentale concentrations reduced the edema. At 50 and 100 mg/kg, an anti-inflammatory response of the EtOAc was observed. Carrageenan stimulus produced a neutrophil count of 28.6% while 50 and 100 mg/kg of the phase reduced this to 14.5% and 9.1%, respectively. The EtOAc extract reduced levels of IL-1 and TNF-α. These results suggest that the EtOAc plays a modulatory role in the inflammatory response. The chromatographic method can be used for the analysis of the phenolic compounds of the EtOAc phase.

  10. 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....

  11. 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.

  12. 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.  

  13. Giant-amplitude, high-work density microactuators with phase transition activated nanolayer bimorphs.

    Science.gov (United States)

    Liu, Kai; Cheng, Chun; Cheng, Zhenting; Wang, Kevin; Ramesh, Ramamoorthy; Wu, Junqiao

    2012-12-12

    Various mechanisms are currently exploited to transduce a wide range of stimulating sources into mechanical motion. At the microscale, simultaneously high amplitude, high work output, and high speed in actuation are hindered by limitations of these actuation mechanisms. Here we demonstrate a set of microactuators fabricated by a simple microfabrication process, showing simultaneously high performance by these metrics, operated on the structural phase transition in vanadium dioxide responding to diverse stimuli of heat, electric current, and light. In both ambient and aqueous conditions, the actuators bend with exceedingly high displacement-to-length ratios up to 1 in the sub-100 μm length scale, work densities over 0.63 J/cm(3), and at frequencies up to 6 kHz. The functionalities of actuation can be further enriched with integrated designs of planar as well as three-dimensional geometries. Combining the superior performance, high durability, diversity in responsive stimuli, versatile working environments, and microscale manufacturability, these actuators offer potential applications in microelectromechanical systems, microfluidics, robotics, drug delivery, and artificial muscles.

  14. 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.

  15. Membrane Active Peptides: Modes-of-Action, Phase Transitions, and Supramolecular Assemblies

    Science.gov (United States)

    Huang, Huey W.

    1997-03-01

    Recent discoveries showed that 20-40 amino-acid peptides are used as very effective antimicrobials in the host-defense systems throughout the animal kingdom, including human. What distinguishes these peptide antimicrobials from the conventional antibiotics is that they attack the lipid matrix of the cytoplasmic membranes rather than protein targets. So the central questions are what are their modes-of-action and how do their distinguish the bacterial cell membranes from the host-cell membranes? Many of these peptides have very simple structures--they are helices with amphiphilic side chains. Despite such simplicities, their interactions with membranes are complex and interesting. The talk will discuss the optical, x-ray and neutron techniques for studying such systems and the experimental as well as theoretical results. The mode-of-action is a phase transition controlled by the concentration of the peptide bound to the membrane. The specificities with respect to membranes are achieved by having different critical concentrations for different lipid composistions of the membrane.

  16. Measuring the noble metal and iodine composition of extracted noble metal phase from spent nuclear fuel using instrumental neutron activation analysis.

    Science.gov (United States)

    Palomares, R I; Dayman, K J; Landsberger, S; Biegalski, S R; Soderquist, C Z; Casella, A J; Brady Raap, M C; Schwantes, J M

    2015-04-01

    Masses of noble metal and iodine nuclides in the metallic noble metal phase extracted from spent fuel are measured using instrumental neutron activation analysis. Nuclide presence is predicted using fission yield analysis, and radionuclides are identified and the masses quantified using neutron activation analysis. The nuclide compositions of noble metal phase derived from two dissolution methods, UO2 fuel dissolved in nitric acid and UO2 fuel dissolved in ammonium-carbonate and hydrogen-peroxide solution, are compared.

  17. Activity and selectivity of palladium catalysts during the liquid-phase hydrogenation of phenol. Influence of temperature and pressure

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Velasco, J.R.; Gonzalez-Marcos, M.P.; Arnaiz, S.; Gutierrez-Ortiz, J.I.; Gutierrez-Ortiz, M.A. [Univ. del Pais Vasco, Bilbao (Spain)

    1995-04-01

    Two series of highly dispersed palladium catalysts supported on alumina have been prepared by adsorption from solution, with palladium contents varying from 0.25 to 2.0 wt %. The first series was calcined at 773 K for 4 h in air, whereas the second series was just heated at 423 K for 1 h in nitrogen, before reduction. Complete dispersion of the metal has been found for the calcined catalysts, and metal dispersion was favored with low palladium contents for the noncalcined catalysts. The kinetic behavior of the catalysts has been analyzed for the liquid-phase hydrogenation of phenol in a stirred tank reactor, ensuring a chemically controlled regime for stirring speed above 750 rpm and catalyst particle below 0.08--0.16 mm in the studied conditions. Despite their higher metallic dispersion, the calcined catalysts presented lower activity than their corresponding noncalcined catalysts. The influence of hydrogen partial pressure on activity showed a reaction order of 2. The apparent activation energy resulted in 56.8 kJ/mol. Selectivity to cyclohexanone was found to be very high for all experiments. Some conclusions on the kinetic reaction rate equations and the apparent activation energies of phenol to cyclohexanone and cyclohexanone to cyclohexanol are given.

  18. 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

  19. Atomic-Scale Determination of Active Facets on the MoVTeNb Oxide M1 Phase and Their Intrinsic Catalytic Activity for Ethane Oxidative Dehydrogenation.

    Science.gov (United States)

    Melzer, Daniel; Xu, Pinghong; Hartmann, Daniela; Zhu, Yuanyuan; Browning, Nigel D; Sanchez-Sanchez, Maricruz; Lercher, Johannes A

    2016-07-25

    Aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) has been used to image the basal {001} plane of the catalytically relevant M1 phase in MoVTeNb complex oxides. Facets {010}, {120}, and {210} are identified as the most frequent lateral termination planes of the crystals. Combination of STEM with He ion microscopy (HIM) images, Rietveld analysis, and kinetic tests reveals that the activation of ethane is correlated to the availability of facets {001}, {120}, and {210} at the surface of M1 crystals. The lateral facets {120} and {210} expose crystalline positions related to the typical active centers described for propane oxidation. Conversely, the low activity of the facet {010} is attributed to its configuration, consisting of only stable M6 O21 units connected by a single octahedron. Thus, we quantitatively demonstrated that differences in catalytic activity among M1 samples of equal chemical composition depend primarily on the morphology of the particles, which determines the predominant terminating facets.

  20. 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...

  1. 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....

  2. 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.

  3. [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.

  4. Session 6: BaCoO{sub 3-y} perovskite as an active phase for the abatement of diesel exhaust pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Milt, V.G.; Ulla, M.A.; Miro, E.E. [Instituto de Investigaciones en Catalisis y Petroquimica - INCAPE (FIQ, UNL-CONICET), Santa Fe (Argentina)

    2004-07-01

    The objective of this work was to study the BaCoO{sub 3-y} system and the interaction between this perovskite-like phase, NO{sub 2} and soot. The obtained experimental results show that BaCoO{sub 3-y} is an active phase for both NO{sub x} adsorption and soot combustion in diesel exhausts. Different crystalline phases are formed upon thermal treatments between 600 C and 1000 C. The solid calcined at a higher temperature shows a higher NO{sub x} storage capacity. The presence of adsorbed NO{sub x} increases the soot combustion activity. (authors)

  5. 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.

  6. 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

  7. 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

    2015-12-07

    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

  8. Influence of anatase and rutile phase in TiO2 upon the photocatalytic degradation of methylene blue under solar irradiation in presence of activated carbon.

    Science.gov (United States)

    Matos, J; Montaña, R; Rivero, E; Escudero, A; Uzcategui, D

    2014-01-01

    The influence of activated carbon (AC) on the photocatalytic activity of different crystalline TiO2 phases was verified in the photocatalytic degradation of methylene blue under UV and solar irradiation. The results showed a volcano trend with a maximum photoactivity for the crystalline phase ratio of anatase:rutile equal to 80:20 both under UV or solar irradiation. By contrast, in presence of AC the photocatalytic activity of the binary materials of TiO2/AC followed an exponential trend, increasing as a function of the increase in anatase proportion in the TiO2 framework. The increase in the photoactivity of the binary material TiO2/AC relative to neat TiO2 was up to 22 and about 17 times higher under UV and visible irradiation, respectively. The present results suggest that AC interacts more efficiently with anatase phase than with rutile phase.

  9. Circadian photosensitive phase and photoperiodic control of testis activity in the mink, a short-day mammal

    Energy Technology Data Exchange (ETDEWEB)

    Boissin-Agasse, L.; Boissin, J.; Ortavant, R.

    1982-02-01

    Evidence of a circadian photosensitive phase in male mink, whose annual reproductive cycle is characterized by the recrudescence of testicular development in autumn, was based on the study of testicular response after interrupting the dark period by light breaks offered at various times. In this mammal, the experimental short days 4L:20D and 8L:16D stimulated testicular growth. Short photoperiods, including a main light period of 3.5 h and an additional 0.5 h light break 7.5 h after the beginning of the main photoperiod, were as effective as 8L:16D in stimulating testicular development. On the other hand, when a 0.5 h light break occurred 11.5 or 15.5 h after the beginning of the main photoperiod, the same inhibiting effect on testicular activity was obtained as for long photoperiods. However, when 0.5 h light breaks were given 19.5 after the beginning of the main light period, some minks recognized, as, the onset of the shorter of the two light periods offered. Thus our results proved the existence of a special phase in the day cycle in which light inhibited testicular development in the mink which appears to be a short-day animal. One explanation of the difference between long-day and short-day animals would be the following: if for long-day animals exposure to light during the photosensitive phase led to gonadostimulation, in short-day mammals, like mink, it exerted an inhibiting influence on testicular growth.

  10. Two phases of V1 activity for visual recognition of natural images.

    Science.gov (United States)

    Camprodon, Joan A; Zohary, Ehud; Brodbeck, Verena; Pascual-Leone, Alvaro

    2010-06-01

    Present theories of visual recognition emphasize the role of interactive processing across populations of neurons within a given network, but the nature of these interactions remains unresolved. In particular, data describing the sufficiency of feedforward algorithms for conscious vision and studies revealing the functional relevance of feedback connections to the striate cortex seem to offer contradictory accounts of visual information processing. TMS is a good method to experimentally address this issue, given its excellent temporal resolution and its capacity to establish causal relations between brain function and behavior. We studied 20 healthy volunteers in a visual recognition task. Subjects were briefly presented with images of animals (birds or mammals) in natural scenes and were asked to indicate the animal category. MRI-guided stereotaxic single TMS pulses were used to transiently disrupt striate cortex function at different times after image onset (SOA). Visual recognition was significantly impaired when TMS was applied over the occipital pole at SOAs of 100 and 220 msec. The first interval has consistently been described in previous TMS studies and is explained as the interruption of the feedforward volley of activity. Given the late latency and discrete nature of the second peak, we hypothesize that it represents the disruption of a feedback projection to V1, probably from other areas in the visual network. These results provide causal evidence for the necessity of recurrent interactive processing, through feedforward and feedback connections, in visual recognition of natural complex images.

  11. Plates soaking prior formation and its influence on positive active material phase composition and battery performance

    Energy Technology Data Exchange (ETDEWEB)

    Foudia, M.; Zerroual, L. [Laboratoire d' Energetique et Electrochimie du Solide (LEES), Universite Ferhat ABBAS Setif 19000 (Algeria); Matrakova, M. [Institute of Electrochemistry and Energy Systems (CLEPS), Bulgarian Academy of Sciences, Sofia 1113 (Bulgaria)

    2009-06-01

    In the present work, we studied the behaviour of 3BS and lead oxide paste as a function of soaking time in two sulfuric acid solutions respectively with 1.05 and 1.20 g cm{sup -3} specific gravity. The study was based on X-ray diffraction analysis (XRD), thermogravimetry (TG), differential scanning calorimetry (DSC) and chemical analysis. The results showed that during plates soaking, 3BS and PbO are converted to monobasic lead sulphate (1BS) and lead sulphate (PbSO{sub 4}). During plate formation in 1.05 s.g. H{sub 2}SO{sub 4} solution, these compounds are oxidized to PbO{sub 2}, the XRD patterns showed that the longer is the time of plates soaking prior formation the lower is {alpha}-PbO{sub 2} content in positive active material. On forming, PbSO{sub 4} crystals convert to {beta}-PbO{sub 2} whereas {alpha}-PbO{sub 2} is a result of 3BS oxidation. The capacity and cycle life of PAM decrease with soaking time, the concentration of the H{sub 2}SO{sub 4} solution during soaking exerts stronger influence than the duration of soaking. (author)

  12. 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.

  13. Comparison of Relative Activation Energies Obtained by Density Functional Theory and the Random Phase Approximation for Several Claisen Rearrangements.

    Science.gov (United States)

    Hartley, Madeline K; Vine, Seanna; Walsh, Elizabeth; Avrantinis, Sara; Daub, G William; Cave, Robert J

    2016-03-03

    We investigate several representative density functional theory approaches for the calculation of relative activation energies and free energies of a set of model pericyclic reactions, some of which have been studied experimentally. In particular, we use a standard hybrid functional (B3LYP), the same hybrid functional augmented with a basis set superposition error and dispersion correction, a meta-hybrid functional developed to treat transition states and weak interactions (M06-2X), and the recently implemented random phase approximation (RPA) based on Kohn-Sham orbitals from conventional density functional theory by Furche and co-workers. We apply these methods to calculate relative activation energies and estimated free energies for the amide acetal Claisen rearrangement. We focus on relative activation energies to assess the effects of steric and weak interactions in the various methods and compare with experiment where possible. We also discuss the advantages of using this set of reactions as a test bed for the comparison of treatments of weak interactions. We conclude that all methods yield similar trends in relative reactivity, but the RPA yields results in best agreement with the experimental values.

  14. 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.

  15. 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.

  16. 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. Depending...

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. Active brickworks - phase I[For application in biofuel boilers]; Aktiva murverk - etapp I

    Energy Technology Data Exchange (ETDEWEB)

    Wrangensten, Lars; Schuster, Robert; Ingman, Rolf; Sendelius, Mikael; Ehleskog, Rickard [AaF-Energikonsult AB, Stockholm (Sweden)

    2003-10-01

    This report is the first step of the R and D project 'Active brickworks' within the program 'Possibilities to improve the operation conditions in industrial bark boilers by optimised combustion control'. Good high temperature resistance is one of the major characteristics of ceramics. They are based on quartz and aluminium oxide, an attachment component (acid or cement) and also different types of additives which, together with the heating treatment, gives the ceramic materials their features. The brickwork in a boiler has several assignments. First of all resistance to corrosion, erosion and protection against fouling of the water tube walls, but also to significant affect the combustion process by energy saving features and heating radiation. This project has been focused on the last named features, namely to be able to make a more active choice of brickwork in order to utilise the ceramic features and hereby making it possible to lower the combustion process emissions. The material samples received from the manufactures have been tested in a small-scale laboratory rig. Features investigated are emissivity/reflection, heat conductivity and heat capacity. Mathematic simulations have also been performed with a representative type boiler model in order to make conclusions concerning how the results can be transformed to and applied in a real full-scale boiler. The most important designing case for ceramics in bark boilers is when boiler load rapidly increases or during a fast fuel moisture change from dry to wet fuel. It has been concluded in the study that that the ceramic walls in a boiler should be divided into different layers. The outer layer in the ceiling and sidewalls of the drying zone must consist of highly insulating material in order to get a high temperature of heating surfaces close to the furnace. To store heat during load transients the heating surfaces must have high emissivity factor and good heating capacity. From this point of

  2. 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

  3. 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...... for about 60 days, at the end of which endpoints of ecological relevance like the sex ratio of the exposed fish is calculated and the biomarker endpoint vitellogenin is measured in individual animals. In 2003, Denmark, on behalf of the European Nordic countries, proposed a new project o develop a Test...... Guideline on the fish sexual development test to the Working Group of the National Coordinators of the Test Guidelines Programme (WNT). The project was included on the Test Guidelines workplan in 2003, and extensive validation of the test method was carried out until 2009. Two validation studies were...

  4. 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

    control strategy, the Absolute Active Power Control (AAPC) can effectively solve the overloading issues by limiting the maximum possible PV power to a certain level (i.e., the power limitation), and also benefit the inverter reliability. However, its feasibility is challenged by the energy loss....... An increase of the inverter lifetime and a reduction of the energy yield can alter the cost of energy, demanding an optimization of the power limitation. Therefore, aiming at minimizing the Levelized Cost 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...

  5. 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.

  6. 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.

  7. 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.

  8. Effect of membrane perturbants on the activity and phase distribution of inositol phosphorylceramide synthase; development of a novel assay.

    Science.gov (United States)

    Aeed, Paul A; Sperry, Andrea E; Young, Casey L; Nagiec, Marek M; Elhammer, Ake P

    2004-07-06

    The effect of 26 different membrane-perturbing agents on the activity and phase distribution of inositol phosphorylceramide synthase (IPC synthase) activity in crude Candida albicans membranes was investigated. The nonionic detergents Triton X-100, Nonidet P-40, Brij, Tween, and octylglucoside all inactivated the enzyme. However, at moderate concentrations, the activity of the Triton X-100- and octylglucoside-solubilized material could be partially restored by inclusion of 5 mM phosphatidylinositol (PI) in the solubilization buffer. The apparent molecular mass of IPC synthase activity solubilized in 2% Triton X-100 was between 1.5 x 10(6) and 20 x 10(6) Da, while under identical conditions, octylglucoside-solubilized activity remained associated with large presumably membrane-like structures. Increased detergent concentrations produced more drastic losses of enzymatic activity. The zwitterionic detergents Empigen BB, N-dodecyl-N,N-(dimethylammonio)butyrate (DDMAB), Zwittergent 3-10, and amidosulfobetaine (ASB)-16 all appeared capable of solubilizing IPC synthase. However, these agents also inactivated the enzyme essentially irreversibly. Solubilization with lysophospholipids again resulted in drastic losses of enzymatic activity that were not restored by the inclusion of PI. Lysophosphatidylinositol also appeared to compete, to some extent, with the donor substrate phosphatidylinositol. The sterol-containing agent digitonin completely inactivated IPC synthase. By contrast, sterol-based detergents such as 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS), 3-[(3-cholamidopropyl)dimethylammonio]-2-hydroxy-1-propanesulfonate (CHAPSO), and taurodeoxycholate (tDOC) had little or no effect on the enzyme activity. The IPC synthase activity in C. albicans membranes remained largely intact and sedimentable at CHAPS concentrations (4%) where >90% of the phospholipids and 60% of the total proteins were extracted from the membranes. At 2.5% CHAPS, a

  9. Electrical activation of carbon δ-doped (Al,Ga)As grown by metalorganic vapour-phase epitaxy

    Science.gov (United States)

    Li, G.; Petravić, M.; Jagadish, C.

    1997-04-01

    Carbon δ-doped (Al,Ga)As was grown by metalorganic vapour-phase epitaxy using trimethylaluminium (TMAl) or trimethylgallium (TMGa) as a doping precursor. The best C δ-doped Al 0.3Ga 0.7As has a peak hole density of 1.6 × 10 19 (1.4 × 10 19 for GaAs) cm -3 with a full hole profile width at half maximum of 85 Å (84 Å for GaAs). For C δ-doped Al 0.3Ga 0.7 As grown at 630°C, the use of TMGa as a doping precursor leads to both the sheet C atom density and the free hole density increasing with an increase in the total TMGa moles introduced during a δ-doping step. As a result, the electrical activation remains almost constant with the change of TMGa moles supplied. The sheet C atom density always increases with increasing supply of TMAl, but approaches its maximum value at an amount of TMAl of 6.4 × 10 -7 mol. The electrical activation reduces from > 90% to pipi doping superlattices with different average hole densities are fabricated to obtain C bulk-doped-like layers.

  10. 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)

  11. Functional Maturation of Neuroendocrine Gonadal Axis is Altered by Specific Phase Relations of Circadian Neurotransmitter Activity in Japanese Quail

    Institute of Scientific and Technical Information of China (English)

    DORISPHILLIPS; CHANDRAMOHINICHATURVEDI

    1995-01-01

    The preset study was designed to ascertain the effects of temporal relationship of circadian neural oscillations on puberty attainment and reproductive growth of Japances Quail,Coturnix coturnix japonica,Serotonin and dopamine precursors(5-hydroxytryptophan,5-HTP and L-dihydroxyphenylalanine,L-DOPA,5mg/100g body weight)were injected daily,8and 12h apart in two groups of one-day ld chick,while cotrols received two daily injections of normal saline.Weekly/biweekly observations(body weight,cloacal gland size,testicular volume and activity,ovarian follicular diameter and rate of egg production)were made until 9 weeks of age,when the experiment was terminated.Results indicate that 8 h relationship completely suppressed gonadal growth even under long photoperiod(LD16:8),while a 12 h relationship induced precocious sexual maturity and increased the rate of reproductin(spermatogenesis and egg production).It is concluded that circadian phase relationship of serotonergic and dopaminergic activity may not only determine the onset of reproduction in this pultry species,but may also alter the rate of reproduction possibly by affecting photoperiodic mechanism of reproductive regulation.

  12. Parvovirus B19 NS1 protein induces cell cycle arrest at G2-phase by activating the ATR-CDC25C-CDK1 pathway

    Science.gov (United States)

    Xu, Peng; Zhou, Zhe; Xiong, Min; Zou, Wei; Deng, Xuefeng; Ganaie, Safder S.; Peng, Jianxin; Liu, Kaiyu; Wang, Shengqi; Ye, Shui Qing

    2017-01-01

    Human parvovirus B19 (B19V) infection of primary human erythroid progenitor cells (EPCs) arrests infected cells at both late S-phase and G2-phase, which contain 4N DNA. B19V infection induces a DNA damage response (DDR) that facilitates viral DNA replication but is dispensable for cell cycle arrest at G2-phase; however, a putative C-terminal transactivation domain (TAD2) within NS1 is responsible for G2-phase arrest. To fully understand the mechanism underlying B19V NS1-induced G2-phase arrest, we established two doxycycline-inducible B19V-permissive UT7/Epo-S1 cell lines that express NS1 or NS1mTAD2, and examined the function of the TAD2 domain during G2-phase arrest. The results confirm that the NS1 TAD2 domain plays a pivotal role in NS1-induced G2-phase arrest. Mechanistically, NS1 transactivated cellular gene expression through the TAD2 domain, which was itself responsible for ATR (ataxia-telangiectasia mutated and Rad3-related) activation. Activated ATR phosphorylated CDC25C at serine 216, which in turn inactivated the cyclin B/CDK1 complex without affecting nuclear import of the complex. Importantly, we found that the ATR-CHK1-CDC25C-CDK1 pathway was activated during B19V infection of EPCs, and that ATR activation played an important role in B19V infection-induced G2-phase arrest. PMID:28264028

  13. Selective pharmacological blockade of the 5-HT7 receptor attenuates light and 8-OH-DPAT induced phase shifts of mouse circadian wheel running activity.

    Science.gov (United States)

    Shelton, Jonathan; Yun, Sujin; Losee Olson, Susan; Turek, Fred; Bonaventure, Pascal; Dvorak, Curt; Lovenberg, Timothy; Dugovic, Christine

    2014-01-01

    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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. Increased CD8+ T cell response to Epstein-Barr virus lytic antigens in the active phase of multiple sclerosis.

    Directory of Open Access Journals (Sweden)

    Daniela F Angelini

    Full Text Available It has long been known that multiple sclerosis (MS is associated with an increased Epstein-Barr virus (EBV seroprevalence and high immune reactivity to EBV and that infectious mononucleosis increases MS risk. This evidence led to postulate that EBV infection plays a role in MS etiopathogenesis, although the mechanisms are debated. This study was designed to assess the prevalence and magnitude of CD8+ T-cell responses to EBV latent (EBNA-3A, LMP-2A and lytic (BZLF-1, BMLF-1 antigens in relapsing-remitting MS patients (n = 113 and healthy donors (HD (n = 43 and to investigate whether the EBV-specific CD8+ T cell response correlates with disease activity, as defined by clinical evaluation and gadolinium-enhanced magnetic resonance imaging. Using HLA class I pentamers, lytic antigen-specific CD8+ T cell responses were detected in fewer untreated inactive MS patients than in active MS patients and HD while the frequency of CD8+ T cells specific for EBV lytic and latent antigens was higher in active and inactive MS patients, respectively. In contrast, the CD8+ T cell response to cytomegalovirus did not differ between HD and MS patients, irrespective of the disease phase. Marked differences in the prevalence of EBV-specific CD8+ T cell responses were observed in patients treated with interferon-β and natalizumab, two licensed drugs for relapsing-remitting MS. Longitudinal studies revealed expansion of CD8+ T cells specific for EBV lytic antigens during active disease in untreated MS patients but not in relapse-free, natalizumab-treated patients. Analysis of post-mortem MS brain samples showed expression of the EBV lytic protein BZLF-1 and interactions between cytotoxic CD8+ T cells and EBV lytically infected plasma cells in inflammatory white matter lesions and meninges. We therefore propose that inability to control EBV infection during inactive MS could set the stage for intracerebral viral reactivation and disease relapse.

  1. 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.

  2. 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.

  3. Local release of pioglitazone (a peroxisome proliferator-activated receptor γ agonist) accelerates proliferation and remodeling phases of wound healing.

    Science.gov (United States)

    Sakai, Shigeki; Sato, Keisuke; Tabata, Yasuhiko; Kishi, Kazuo

    2016-01-01

    Peroxisome proliferator-activated receptor γ (PPARγ) is a member of the nuclear receptor superfamily known for its anti-inflammatory and macrophage differentiation effects, as well as its ability to promote fat cell differentiation and reduce insulin resistance. Pioglitazone (Pio) is a PPARγ agonist used clinically as an anti-diabetic agent for improving insulin sensitivity in patients with diabetes. The objective of this study was to develop a drug delivery system (DDS) for the local release of Pio to promote wound healing. Pio of low aqueous solubility was water-solubilized by micelles formed from gelatin grafted with L-lactic acid oligomers, and incorporated into a biodegradable gelatin hydrogel. An 8-mm punch biopsy tool was used to prepare two skin wounds on either side of the midline of 8-week-old mice. Wounds were treated by the hydrogels with (Pio-hydrogel group) or without (control group) Pio, and the wound area were observed 1, 4, 7, and 14 days after treatment. In addition, a protein assay and immunohistological stain were performed to determine the effects of the Pio-hydrogel on inflammation and macrophage differentiation. The Pio-hydrogels promote wound healing. Moreover, Western blotting analysis demonstrated that treatment with Pio-hydrogels resulted in decreased levels of the cytokines MIP-2 and TGF-β, and increased levels of glucose-regulating adiponectin. It is concluded that Pio-incorporated hydrogels promote the proliferation and remodeling phases of wound healing, and may prove to be effective as wound dressings.

  4. 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.

  5. 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

  6. Sequential Assessment of Cell Cycle S Phase in Flow Cytometry: A Non-Isotopic Method to Measure Lymphocyte Activation In Vitro

    Directory of Open Access Journals (Sweden)

    Ch. Kohler

    1997-01-01

    Full Text Available Lymphocyte multiplication can be induced in vitro by mitogens or specific antigens, and is usually measured using isotopic methods involving tritiated thymidine. Cellular proliferation can also be analyzed by flow cytometry techniques based on cell cycle analysis through the measurement of DNA content. We applied this method to lymphocytes from 113 individuals, to evaluate lymphocyte proliferation after stimulation in vitro by a mitogen (phytohaemagglutinin, PHA or a recall antigen (tetanus toxoid, using a kinetic approach with four points sequential measurements of the S and G2 phases over six days of culture. The proportion of cells in S phase after PHA stimulation was significantly higher than in controls overall and as early as on day three of the culture. Activation with a recall antigen significantly induced increasing S phase cell proportions up to day six. These data suggest that flow cytometric assessment of the S phase could be a useful alternative to isotopic methods measuring lymphocyte reactivity in vitro.

  7. 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.

  8. 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.

  9. 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

  10. 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...

  11. 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.

  12. 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

  13. 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

  14. 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…

  15. 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.

  16. Rate Constants and Activation Energies for Gas‐Phase Reactions of Three Cyclic Volatile Methyl Siloxanes with the Hydroxyl Radical

    Science.gov (United States)

    Safron, Andreas; Strandell, Michael; Kierkegaard, Amelie

    2015-01-01

    ABSTRACT Reaction with hydroxyl radicals (OH) is the major pathway for removal of cyclic volatile methyl siloxanes (cVMS) from air. We present new measurements of second‐order rate constants for reactions of the cVMS octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) with OH determined at temperatures between 313 and 353 K. Our measurements were made using the method of relative rates with cyclohexane as a reference substance and were conducted in a 140‐mL gas‐phase reaction chamber with online mass spectrometry analysis. When extrapolated to 298 K, our measured reaction rate constants of D4 and D5 with the OH radical are 1.9 × 10−12 (95% confidence interval (CI): (1.7–2.2) × 10−12) and 2.6 × 10−12 (CI: (2.3–2.9) × 10−12) cm3 molecule−1 s−1, respectively, which are 1.9× and 1.7× faster than previous measurements. Our measured rate constant for D6 is 2.8 × 10−12 (CI: (2.5–3.2) × 10−12) cm3 molecule−1 s−1 and to our knowledge there are no comparable laboratory measurements in the literature. Reaction rates for D5 were 33% higher than for D4 (CI: 30–37%), whereas the rates for D6 were only 8% higher than for D5 (CI: 5–10%). The activation energies of the reactions of D4, D5, and D6 with OH were not statistically different and had a value of 4300 ± 2800 J/mol. PMID:27708500

  17. Rate Constants and Activation Energies for Gas-Phase Reactions of Three Cyclic Volatile Methyl Siloxanes with the Hydroxyl Radical.

    Science.gov (United States)

    Safron, Andreas; Strandell, Michael; Kierkegaard, Amelie; Macleod, Matthew

    2015-07-01

    Reaction with hydroxyl radicals (OH) is the major pathway for removal of cyclic volatile methyl siloxanes (cVMS) from air. We present new measurements of second-order rate constants for reactions of the cVMS octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) with OH determined at temperatures between 313 and 353 K. Our measurements were made using the method of relative rates with cyclohexane as a reference substance and were conducted in a 140-mL gas-phase reaction chamber with online mass spectrometry analysis. When extrapolated to 298 K, our measured reaction rate constants of D4 and D5 with the OH radical are 1.9 × 10(-12) (95% confidence interval (CI): (1.7-2.2) × 10(-12)) and 2.6 × 10(-12) (CI: (2.3-2.9) × 10(-12)) cm(3) molecule(-1) s(-1), respectively, which are 1.9× and 1.7× faster than previous measurements. Our measured rate constant for D6 is 2.8 × 10(-12) (CI: (2.5-3.2) × 10(-12)) cm(3) molecule(-1) s(-1) and to our knowledge there are no comparable laboratory measurements in the literature. Reaction rates for D5 were 33% higher than for D4 (CI: 30-37%), whereas the rates for D6 were only 8% higher than for D5 (CI: 5-10%). The activation energies of the reactions of D4, D5, and D6 with OH were not statistically different and had a value of 4300 ± 2800 J/mol.

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. Tm-doped TiO2 and Tm2Ti2O7 pyrochlore nanoparticles: enhancing the photocatalytic activity of rutile with a pyrochlore phase

    Directory of Open Access Journals (Sweden)

    Desiré M. De los Santos

    2015-03-01

    Full Text Available Tm-doped TiO2 nanoparticles were synthesized using a water-controlled hydrolysis reaction. Analysis was performed in order to determine the influence of the dopant concentration and annealing temperature on the phase, crystallinity, and electronic and optical properties of the resulting material. Various characterization techniques were utilized such as X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy and UV–vis spectroscopy. For the samples annealed at 773 and 973 K, anatase phase TiO2 was obtained, predominantly internally doped with Tm3+. ICP–AES showed that a doping concentration of up to 5.8 atom % was obtained without reducing the crystallinity of the samples. The presence of Tm3+ was confirmed by X-ray photoelectron spectroscopy and UV–vis spectroscopy: the incorporation of Tm3+ was confirmed by the generation of new absorption bands that could be assigned to Tm3+ transitions. Furthermore, when the samples were annealed at 1173 K, a pyrochlore phase (Tm2Ti2O7 mixed with TiO2 was obtained with a predominant rutile phase. The photodegradation of methylene blue showed that this pyrochlore phase enhanced the photocatalytic activity of the rutile phase.

  3. 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.

  4. One-Wave Optical Phase Conjugation Mirror by Actively Coupling Arbitrary Light Fields into a Single-Mode Reflector

    Science.gov (United States)

    Lee, KyeoReh; Lee, Junsung; Park, Jung-Hoon; Park, Ji-Ho; Park, YongKeun

    2015-10-01

    Rewinding the arrow of time via phase conjugation is an intriguing phenomenon made possible by the wave property of light. Here, we demonstrate the realization of a one-wave optical phase conjugation mirror using a spatial light modulator. An adaptable single-mode filter is created, and a phase-conjugate beam is then prepared by reverse propagation through this filter. Our method is simple, alignment free, and fast while allowing high power throughput in the time-reversed wave, which has not been simultaneously demonstrated before. Using our method, we demonstrate high throughput full-field light delivery through highly scattering biological tissue and multimode fibers, even for quantum dot fluorescence.

  5. Effect of ionic liquids as the mobile phase additives on the HPLC resolution of four active compounds from Sophora flavescens Ait.

    Science.gov (United States)

    Tian, Minglei; Liu, Junyu; Row, Kyung Ho

    2009-06-11

    The retention behaviour of four active compounds from Sophora Flavescens Ait using three ionic liquids as mobile phase modifiers was examined. The effect of the pH and the amount of ionic liquid modifier on the retention of these compounds was determined in methanol/water (v/v) as the mobile phase containing different ionic liquids ranging in concentration from 0.1 mmol/L to 3.0 mmol/L. The ionic liquids showed promise as additives in high-performance liquid chromatography.

  6. 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.

  7. 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.

  8. Experimental Testing and Model Validation of a Decoupled-Phase On-Load Tap Changer Transformer in an Active Network

    OpenAIRE

    Zecchino, Antonio; Hu, Junjie; Coppo, Massimiliano; Marinelli, Mattia

    2016-01-01

    Due to the increasing penetration of single-phase small generation units and electric vehiclesconnected to distribution grids, system operators are facing challenges related to local unbalanced voltagerise or drop issues, which may lead to a violation of the allowed voltage band. To address this problem,distribution transformers with on-load tapping capability are under development. This paper presentsmodel and experimental validation of a 35 kVA three-phase power distribution transformer wit...

  9. Preparation and thermal properties of form-stable palmitic acid/active aluminum oxide composites as phase change materials for latent heat storage

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Guiyin, E-mail: gyfang@nju.edu.cn [School of Physics, Nanjing University, Nanjing 210093 (China); Li, Hui [Department of Material Science and Engineering, Nanjing University, Nanjing 210093 (China); Cao, Lei; Shan, Feng [School of Physics, Nanjing University, Nanjing 210093 (China)

    2012-12-14

    Form-stable palmitic acid (PA)/active aluminum oxide composites as phase change materials were prepared by adsorbing liquid palmitic acid into active aluminum oxide. In the composites, the palmitic acid was used as latent heat storage materials, and the active aluminum oxide was used as supporting material. Fourier transformation infrared spectroscope (FT-IR), X-ray diffractometer (XRD) and scanning electronic microscope (SEM) were used to determine the chemical structure, crystalloid phase and microstructure of the composites, respectively. The thermal properties and thermal stability were investigated by a differential scanning calorimeter (DSC) and a thermogravimetry analyzer (TGA). The FT-IR analyses results indicated that there is no chemical interaction between the palmitic acid and active aluminum oxide. The SEM results showed that the palmitic acid was well adsorbed into porous network of the active aluminum oxide. The DSC results indicated that the composites melt at 60.25 Degree-Sign C with a latent heat of 84.48 kJ kg{sup -1} and solidify at 56.86 Degree-Sign C with a latent heat of 78.79 kJ kg{sup -1} when the mass ratio of the PA to active aluminum oxide is 0.9:1. Compared with that of the PA, the melting and solidifying time of the composites CPCM5 was reduced by 20.6% and 21.4% because of the increased heat transfer rate through EG addition. The TGA results showed that the active aluminum oxide can improve the thermal stability of the composites. -- Highlights: Black-Right-Pointing-Pointer Form-stable PA/active aluminum oxide composites as PCMs were prepared. Black-Right-Pointing-Pointer Chemical structure, crystalloid phase and microstructure of composites were determined. Black-Right-Pointing-Pointer Thermal properties and thermal stability of the composites were investigated. Black-Right-Pointing-Pointer Expanded graphite can improve thermal conductivity of the composites.

  10. Gender-specific cerebral activation during cognitive tasks using functional MRI: comparison of women in mid-luteal phase and men

    Energy Technology Data Exchange (ETDEWEB)

    Gizewski, Elke R.; Wanke, Isabel; Forsting, Michael [University Hospital Essen, Departments of Diagnostic and Interventional Neuroradiology, Essen (Germany); Krause, Eva; Senf, Wolfgang [University Hospital Essen, Department of Psychosomatic Medicine, Essen (Germany)

    2006-01-01

    Previous studies of gender-specific differences in functional imaging during spatial and language tasks have been inconclusive. Furthermore, among women, such differences may occur during mid-luteal phase compared to the rest of the menstrual cycle. In order to examine further gender differences, functional MRI was performed in 12 male volunteers and 12 female volunteers (in the mid-luteal phase) during mental rotation and verb-generation tests. Two-sample t-tests with uncorrected P values of <0.001 for the specific regions of interest (ROIs) revealed cerebral activation differences in both stimuli. During mental rotation tests, higher levels of activation were noted in the right medial frontal, precentral, and bilateral inferior parietal cortex, while in women this occurred in the right inferior and medial temporal, right superior frontal cortex, and left fusiform gyrus. During verb-generation tests, higher levels of activation in men was found in the left medial temporal and precentral cortex. Our results indicate that differences in cerebral activity during cognitive tasks can be shown between men and women in the mid-luteal phase. Gender differences while performing a mental rotation task were more prominent than during a verb-generation task. (orig.)

  11. Inhibition of mixed-lineage kinase (MLK) activity during G2-phase disrupts microtubule formation and mitotic progression in HeLa cells.

    Science.gov (United States)

    Cha, Hyukjin; Dangi, Surabhi; Machamer, Carolyn E; Shapiro, Paul

    2006-01-01

    The mixed-lineage kinases (MLK) are serine/threonine protein kinases that regulate mitogen-activated protein (MAP) kinase signaling pathways in response to extracellular signals. Recent studies indicate that MLK activity may promote neuronal cell death through activation of the c-Jun NH2-terminal kinase (JNK) family of MAP kinases. Thus, inhibitors of MLK activity may be clinically useful for delaying the progression of neurodegenerative diseases, such as Parkinson's. In proliferating non-neuronal cells, MLK may have the opposite effect of promoting cell proliferation. In the current studies we examined the requirement for MLK proteins in regulating cell proliferation by examining MLK function during G2 and M-phase of the cell cycle. The MLK inhibitor CEP-11004 prevented HeLa cell proliferation by delaying mitotic progression. Closer examination revealed that HeLa cells treated with CEP-11004 during G2-phase entered mitosis similar to untreated G2-phase cells. However, CEP-11004 treated cells failed to properly exit mitosis and arrested in a pro-metaphase state. Partial reversal of the CEP-11004 induced mitotic arrest could be achieved by overexpression of exogenous MLK3. The effects of CEP-11004 treatment on mitotic events included the inhibition of histone H3 phosphorylation during prophase and prior to nuclear envelope breakdown and the formation of aberrant mitotic spindles. These data indicate that MLK3 might be a unique target to selectively inhibit transformed cell proliferation by disrupting mitotic spindle formation resulting in mitotic arrest.

  12. 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.

  13. A conserved Polϵ binding module in Ctf18-RFC is required for S-phase checkpoint activation downstream of Mec1.

    Science.gov (United States)

    García-Rodríguez, Luis J; De Piccoli, Giacomo; Marchesi, Vanessa; Jones, Richard C; Edmondson, Ricky D; Labib, Karim

    2015-10-15

    Defects during chromosome replication in eukaryotes activate a signaling pathway called the S-phase checkpoint, which produces a multifaceted response that preserves genome integrity at stalled DNA replication forks. Work with budding yeast showed that the 'alternative clamp loader' known as Ctf18-RFC acts by an unknown mechanism to activate the checkpoint kinase Rad53, which then mediates much of the checkpoint response. Here we show that budding yeast Ctf18-RFC associates with DNA polymerase epsilon, via an evolutionarily conserved 'Pol ϵ binding module' in Ctf18-RFC that is produced by interaction of the carboxyl terminus of Ctf18 with the Ctf8 and Dcc1 subunits. Mutations at the end of Ctf18 disrupt the integrity of the Pol ϵ binding module and block the S-phase checkpoint pathway, downstream of the Mec1 kinase that is the budding yeast orthologue of mammalian ATR. Similar defects in checkpoint activation are produced by mutations that displace Pol ϵ from the replisome. These findings indicate that the association of Ctf18-RFC with Pol ϵ at defective replication forks is a key step in activation of the S-phase checkpoint.

  14. Activity of Catalyst for Liquid Phase Methanol Synthesis%液相合成甲醇催化剂活性的研究

    Institute of Scientific and Technical Information of China (English)

    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 523 K, 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.

  15. Phases and Phase Transitions

    Science.gov (United States)

    Gitterman, Moshe

    2014-09-01

    In discussing phase transitions, the first thing that we have to do is to define a phase. This is a concept from thermodynamics and statistical mechanics, where a phase is defined as a homogeneous system. As a simple example, let us consider instant coffee. This consists of coffee powder dissolved in water, and after stirring it we have a homogeneous mixture, i.e., a single phase. If we add to a cup of coffee a spoonful of sugar and stir it well, we still have a single phase -- sweet coffee. However, if we add ten spoonfuls of sugar, then the contents of the cup will no longer be homogeneous, but rather a mixture of two homogeneous systems or phases, sweet liquid coffee on top and coffee-flavored wet sugar at the bottom...

  16. Sinorhizobium meliloti sigma factors RpoE1 and RpoE4 are activated in stationary phase in response to sulfite.

    Science.gov (United States)

    Bastiat, Bénédicte; Sauviac, Laurent; Picheraux, Carole; Rossignol, Michel; Bruand, Claude

    2012-01-01

    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.

  17. 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.

  18. 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

  19. 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.

  20. 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.

  1. Characterization of functionally active interleukin-18/eGFP fusion protein expression during cell cycle phases in recombinant chicken DF1 Cells.

    Science.gov (United States)

    Wu, Hsing Chieh; Chen, Yu San; Shien, Jui Hung; Shen, Pin Chun; Lee, Long Huw

    2016-05-01

    The dependence of foreign gene expression on cell cycle phases in mammalian cells has been described. In this study, a DF1/chIL-18a cell line that stably expresses the fusion protein chIL-18 was constructed and the enhanced green fluorescence protein connected through a (G4 S)3 linker sequence investigated the relationship between cell cycle phases and fusion protein production. DF1/chIL-18a cells (1 × 10(5) ) were inoculated in 60-mm culture dishes containing 5 mL of media to achieve 50%-60% confluence and were cultured in the presence of the cycle-specific inhibitors 10058-F4, aphidicolin, and colchicine for 24 and 48 h. The percentage of cell density and mean fluorescence intensity in each cell cycle phase were assessed using flow cytometry. The inhibitors effectively arrested cell growth. The fusion protein production rate was higher in the S phase than in the G0/G1 and G2/M phases. When cell cycle progression was blocked in the G0/G1, S, and G2/M phases by the addition of 10058-F4, aphidicolin, and colchicine, respectively, the aphidicolin-induced single cells showed higher fusion protein levels than did the 10058-F4- or colchicine-induced phase cells and the uninduced control cells. Although the cells did not proliferate after the drug additions, the amount of total fusion protein accumulated in aphidicolin-treated cells was similar to that in the untreated cultures. Fusion protein is biologically active because it induces IFN-γ production in splenocyte cultures of chicken. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:581-591, 2016.

  2. 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.

  3. Cannabidiol Post-Treatment Alleviates Rat Epileptic-Related Behaviors and Activates Hippocampal Cell Autophagy Pathway Along with Antioxidant Defense in Chronic Phase of Pilocarpine-Induced Seizure.

    Science.gov (United States)

    Hosseinzadeh, Mahshid; Nikseresht, Sara; Khodagholi, Fariba; Naderi, Nima; Maghsoudi, Nader

    2016-04-01

    Abnormal and sometimes severe behavioral and molecular symptoms are usually observed in epileptic humans and animals. To address this issue, we examined the behavioral and molecular aspects of seizure evoked by pilocarpine. Autophagy can promote both cell survival and death, but there are controversial reports about the neuroprotective or neurodegenerative effects of autophagy in seizure. Cannabidiol has anticonvulsant properties in some animal models when used as a pretreatment. In this study, we investigated alteration of seizure scores, autophagy pathway proteins, and antioxidant status in hippocampal cells during the chronic phase of pilocarpine-induced epilepsy after treatment with cannabidiol. Cannabidiol (100 ng, intracerebroventricular injection) delayed the chronic phase of epilepsy. Single administration of cannabidiol during the chronic phase of seizure significantly diminished seizure scores such as mouth clonus, head nodding, monolateral and bilateral forelimb clonus and increased the activity of catalase enzyme and reduced glutathione content. Such a protective effect in the behavioral scores of epileptic rats was also observed after repeated administrations of cannabidiol at the onset of the silent phase. Moreover, the amount of Atg7, conjugation of Atg5/12, Atg12, and LC3II/LC3I ratio increased significantly in epileptic rats treated with repeated injections of cannabidiol. In short, our results suggest that post-treatment of Cannabidiol could enhance the induction of autophagy pathway and antioxidant defense in the chronic phase of epilepsy, which could be considered as the protective mechanisms of cannabidiol in a temporal lobe epilepsy model.

  4. Hysteresis Effect in the Activity Indices of the Atmospheres of the Sun and Solar-Type Stars During the Rising and Falling Phases of Cycles

    Science.gov (United States)

    Bruevich, E. A.; Yakunina, G. V.

    2016-09-01

    The hysteresis effect that shows up as a nonunique relationship among the emissions from the photosphere, chromosphere, and corona during the rising and falling phases of solar and stellar activity is analyzed. The following solar indices are analyzed and compared in different phases of the cycle: the radiative flux in the hydrogen Lyman alpha line FLα, radio emission at 10.7 cm F10.7, the sunspot number SSN, the radiative flux in the 530.0 nm green coronal line F530.3, the solar constant TSI, and the relative flux ratio c/w (ratio of the fluxes in the center and in the wings) for the 280 nm Mg II line. In stars with cycles, a hysteresis effect is observed between the CaII chromospheric S-activity index for stars in the Mount Wilson HK project and the photospheric flux Fph for these stars.

  5. Randomized phase I: safety, immunogenicity and mucosal antiviral activity in young healthy women vaccinated with HIV-1 Gp41 P1 peptide on virosomes

    OpenAIRE

    Geert Leroux-Roels; Cathy Maes; Frédéric Clement; Frank van Engelenburg; Marieke van den Dobbelsteen; Michael Adler; Mario Amacker; Lucia Lopalco; Morgane Bomsel; Anick Chalifour; Sylvain Fleury

    2013-01-01

    UNLABELLED: Mucosal antibodies harboring various antiviral activities may best protect mucosal surfaces against early HIV-1 entry at mucosal sites and they should be ideally induced by prophylactic HIV-1 vaccines for optimal prevention of sexually transmitted HIV-1. A phase I, double-blind, randomized, placebo-controlled trial was conducted in twenty-four healthy HIV-uninfected young women. The study objectives were to assess the safety, tolerability and immunogenicity of virosomes harboring ...

  6. The changes of blood platelet activation in breast cancer patients before surgery, after surgery, and in various phases of the chemotherapy.

    Science.gov (United States)

    Kedzierska, Magdalena; Czernek, Urszula; Szydłowska-Pazera, Katarzyna; Potemski, Piotr; Piekarski, Janusz; Jeziorski, Arkadiusz; Olas, Beata

    2013-01-01

    Blood platelets from patients with cancer (before or after the surgery) exhibit a variety of qualitative abnormalities. Different anti-cancer drugs may also induce the oxidative/nitrative stress in blood platelets and change their hemostatic properties. The aim of our study was to explain the effect of superoxide anion radicals ([Formula: see text]) production on hemostatic properties of blood platelets (activated by a strong physiological agonist - thrombin) from breast cancer patients before the surgery, after the surgery, and after various phases (I-IV) of chemotherapy (doxorubicin and cyclophosphamide). Patients were hospitalized in the Department of Oncological Surgery and at the Department of Chemotherapy, Medical University of Lodz, Poland. We measured the platelet aggregation as the marker of hemostatic activity of blood platelets. We observed an increase of [Formula: see text] in thrombin-activated blood platelets from patients with breast cancer (before or after the surgery and after various phases of the chemotherapy) compared to the healthy group. Our other experiments demonstrated that aggregation (induced by thrombin) of blood platelets from patients with breast cancer before the surgery, after the surgery, and after various phases of the chemotherapy differs from aggregation of platelets obtained from healthy volunteers. Moreover, our results showed the correlation between the [Formula: see text] generation and changes of platelet aggregation in breast cancer patients before the surgery, after the surgery, and after the chemotherapy (I and IV phases). Considering the data presented in this study, we suggest that the production of [Formula: see text] in blood platelets (activated by thrombin) obtained from breast cancer patients may induce the changes of platelet aggregation, which may contribute in thrombosis in these patients.

  7. 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).

  8. 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.

  9. UV and visible light photocatalytic activity of Au/TiO2 nanoforests with Anatase/Rutile phase junctions and controlled Au locations

    Science.gov (United States)

    Yu, Yang; Wen, Wei; Qian, Xin-Yue; Liu, Jia-Bin; Wu, Jin-Ming

    2017-01-01

    To magnify anatase/rutile phase junction effects through appropriate Au decorations, a facile solution-based approach was developed to synthesize Au/TiO2 nanoforests with controlled Au locations. The nanoforests cons®isted of anatase nanowires surrounded by radially grown rutile branches, on which Au nanoparticles were deposited with preferred locations controlled by simply altering the order of the fabrication step. The Au-decoration increased the photocatalytic activity under the illumination of either UV or visible light, because of the beneficial effects of either electron trapping or localized surface plasmon resonance (LSPR). Gold nanoparticles located preferably at the interface of anatase/rutile led to a further enhanced photocatalytic activity. The appropriate distributions of Au nanoparticles magnify the beneficial effects arising from the anatase/rutile phase junctions when illuminated by UV light. Under the visible light illumination, the LSPR effect followed by the consecutive electron transfer explains the enhanced photocatalysis. This study provides a facile route to control locations of gold nanoparticles in one-dimensional nanostructured arrays of multiple-phases semiconductors for achieving a further increased photocatalytic activity.

  10. UV and visible light photocatalytic activity of Au/TiO2 nanoforests with Anatase/Rutile phase junctions and controlled Au locations.

    Science.gov (United States)

    Yu, Yang; Wen, Wei; Qian, Xin-Yue; Liu, Jia-Bin; Wu, Jin-Ming

    2017-01-24

    To magnify anatase/rutile phase junction effects through appropriate Au decorations, a facile solution-based approach was developed to synthesize Au/TiO2 nanoforests with controlled Au locations. The nanoforests cons®isted of anatase nanowires surrounded by radially grown rutile branches, on which Au nanoparticles were deposited with preferred locations controlled by simply altering the order of the fabrication step. The Au-decoration increased the photocatalytic activity under the illumination of either UV or visible light, because of the beneficial effects of either electron trapping or localized surface plasmon resonance (LSPR). Gold nanoparticles located preferably at the interface of anatase/rutile led to a further enhanced photocatalytic activity. The appropriate distributions of Au nanoparticles magnify the beneficial effects arising from the anatase/rutile phase junctions when illuminated by UV light. Under the visible light illumination, the LSPR effect followed by the consecutive electron transfer explains the enhanced photocatalysis. This study provides a facile route to control locations of gold nanoparticles in one-dimensional nanostructured arrays of multiple-phases semiconductors for achieving a further increased photocatalytic activity.

  11. UV and visible light photocatalytic activity of Au/TiO2 nanoforests with Anatase/Rutile phase junctions and controlled Au locations

    Science.gov (United States)

    Yu, Yang; Wen, Wei; Qian, Xin-Yue; Liu, Jia-Bin; Wu, Jin-Ming

    2017-01-01

    To magnify anatase/rutile phase junction effects through appropriate Au decorations, a facile solution-based approach was developed to synthesize Au/TiO2 nanoforests with controlled Au locations. The nanoforests cons®isted of anatase nanowires surrounded by radially grown rutile branches, on which Au nanoparticles were deposited with preferred locations controlled by simply altering the order of the fabrication step. The Au-decoration increased the photocatalytic activity under the illumination of either UV or visible light, because of the beneficial effects of either electron trapping or localized surface plasmon resonance (LSPR). Gold nanoparticles located preferably at the interface of anatase/rutile led to a further enhanced photocatalytic activity. The appropriate distributions of Au nanoparticles magnify the beneficial effects arising from the anatase/rutile phase junctions when illuminated by UV light. Under the visible light illumination, the LSPR effect followed by the consecutive electron transfer explains the enhanced photocatalysis. This study provides a facile route to control locations of gold nanoparticles in one-dimensional nanostructured arrays of multiple-phases semiconductors for achieving a further increased photocatalytic activity. PMID:28117448

  12. 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

    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...

  13. 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...... performed microinjection and transfection experiments using rat R12 fibroblasts, their derivatives conditionally overexpressing cyclins D1 or E, and human U-2-OS cells, to explore the action of G1 cyclins and the relationship of E2F and cyclin E in S-phase induction. We demonstrate that ectopic expression...... that the cyclin E-induced S phase and completion of the cell division cycle can occur in the absence of E2F-mediated transactivation. Together with the ability of cyclin E to overcome a G1 block induced by expression of dominant-negative mutant DP-1, a heterodimeric partner of E2Fs, these results provide evidence...

  14. 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…

  15. In vitro activity of ceftobiprole against pathogens from two phase 3 clinical trials of complicated skin and skin structure infections.

    Science.gov (United States)

    Amsler, Karen M; Davies, Todd A; Shang, Wenchi; Jacobs, Michael R; Bush, Karen

    2008-09-01

    In phase 3 clinical trials for ceftobiprole treatment of complicated skin and skin structure infections, 1,219 gram-positive and 276 gram-negative aerobic baseline pathogens were identified. Ceftobiprole inhibited all staphylococcal isolates, including methicillin-resistant strains, at MICs of ceftobiprole was similar to that of cefepime.

  16. 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...

  17. 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.

  18. 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

    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...

  19. 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.

  20. 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.

  1. Transcriptome Analysis of Spermatogenically Regressed, Recrudescent and Active Phase Testis of Seasonally Breeding Wall Lizards Hemidactylus flaviviridis

    OpenAIRE

    Mukesh Gautam; Amitabh Mathur; Meraj Alam Khan; Majumdar, Subeer S.; Umesh Rai

    2013-01-01

    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 r...

  2. In Vitro Activity of Ceftobiprole against Pathogens from Two Phase 3 Clinical Trials of Complicated Skin and Skin Structure Infections▿

    OpenAIRE

    2008-01-01

    In phase 3 clinical trials for ceftobiprole treatment of complicated skin and skin structure infections, 1,219 gram-positive and 276 gram-negative aerobic baseline pathogens were identified. Ceftobiprole inhibited all staphylococcal isolates, including methicillin-resistant strains, at MICs of ≤4 μg/ml. Against Enterobacteriaceae and Pseudomonas aeruginosa isolates, the potency of ceftobiprole was similar to that of cefepime.

  3. Development of a dispatchable PV peak shaving system. Final report on PV:BONUS Phase 2 activities

    Energy Technology Data Exchange (ETDEWEB)

    Ferguson, W.D. [Conectiv, Inc., Wilmington, DE (United States); Nigro, R.M. [Applied Energy Group, Inc., Hauppauge, NY (United States)

    1999-01-20

    In July 1993, the Delmarva Power and Light Company (now Conectiv, Inc.) was awarded a contract for the development of a Dispatchable Photovoltaic Peak Shaving System under the US Department of Energy PV:BONUS Program. The rationale for the dispatchable PV peak shaving system is based on the coincidence between the solar resource and the electrical load in question. Where poor coincidence exists, a PV array by itself does little to offset peak demands. However, with the addition of a relatively small amount of energy storage, the energy from the PV array can be managed and the value of the PV system increases substantially. In Phase 2, Delmarva Power continued the refinement of the system deployed in Phase 1. Four additional dispatchable PV peak shaving systems were installed for extended testing and evaluation at sites in Delaware, Maryland, Wisconsin and North Carolina. A second type of system that can be used to provide back-up power as well as peak shaving was also developed in Phase 2. This PV-UPS system used a packaging approach nearly identical to the PV peak shaving system, although there were significant differences in the design of the power electronics and control systems. Conceptually, the PV-UPS system builds upon the idea of adding value to PV systems by increasing functionality. A prototype of the PV-UPS system was installed in Delaware for evaluation near the end of the contract period.

  4. 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.

  5. Determination of UV active inorganic anions in potable and high salinity water by ion pair reversed phase liquid chromatography.

    Science.gov (United States)

    Sadiq Khan, Sadaf; Riaz, M

    2014-05-01

    Reversed phase column was dynamically modified into anion exchange column using various types of tetraalkylammonium salts as ion pair reagents (IPRs) for the separation and quantification of toxic anions such as nitrite, bromate, bromide and nitrate in potable and high salinity water. Various chromatographic parameters such as types and concentration of IPRs, concentration of organic modifier, phosphate buffer and mobile phase pH were optimized for the base-line separation of anions. The lowest detection limits (LDLs) were 0.2 for nitrate and nitrite, 0.6 µg ml(-1)for bromate and bromide respectively for potable water samples. NaCl and Na₂SO₄ were incorporated in the mobile phase for the analysis of high salinity water samples to minimize matrix interferences. This has resulted in change in elution order of anions, better tolerance of matrix anions such as chloride and sulphate. The developed method was successfully utilized for analysis of anions in potable, high salinity and sea water samples.

  6. 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.

  7. Maximizing the utilization of Laminaria japonica as biomass via improvement of alginate lyase activity in a two-phase fermentation system.

    Science.gov (United States)

    Oh, Yuri; Xu, Xu; Kim, Ji Young; Park, Jong Moon

    2015-08-01

    Brown seaweed contains up to 67% of carbohydrates by dry weight and presents high potential as a polysaccharide feedstock for biofuel production. To effectively use brown seaweed as a biomass, degradation of alginate is the major challenge due to its complicated structure and low solubility in water. This study focuses on the isolation of alginate degrading bacteria, determining of the optimum fermentation conditions, as well as comparing the conventional single fermentation system with the two-phase fermentation system which is separately using alginate and mannitol extracted from Laminaria japonica. Maximum yield of organic acids production and volatile solids reduction obtained were 0.516 g/g and 79.7%, respectively, using the two-phase fermentation system in which alginate fermentation was carried out at pH 7 and mannitol fermentation at pH 8. The two-phase fermentation system increased the yield of organic acids production by 1.14 times and led to a 1.45-times reduction of VS when compared to the conventional single fermentation system at pH 8. The results show that the two-phase fermentation system improved the utilization of alginate by separating alginate from mannitol leading to enhanced alginate lyase activity.

  8. Synergistic Effects of Sm and C Co-Doped Mixed Phase Crystalline TiO2 for Visible Light Photocatalytic Activity

    Directory of Open Access Journals (Sweden)

    Fuchang Peng

    2017-02-01

    Full Text Available Mixed phase TiO2 nanoparticles with element doping by Sm and C were prepared via a facile sol-gel procedure. The UV-Vis light-diffuse reflectance spectroscopy analysis showed that the absorption region of co-doped TiO2 was shifted to the visible-light region, which was attributed to incorporation of samarium and carbon into the TiO2 lattice during high-temperature reaction. Samarium effectively decreased the anatase-rutile phase transformation. The grain size can be controlled by Sm doping to achieve a large specific surface area useful for the enhancement of photocatalytic activity. The photocatalytic activities under visible light irradiation were evaluated by photocatalytic degradation of methylene blue (MB. The degradation rate of MB over the Sm-C co-doped TiO2 sample was the best. Additionally, first-order apparent rate constants increased by about 4.3 times compared to that of commercial Degusssa P25 under the same experimental conditions. Using different types of scavengers, the results indicated that the electrons, holes, and •OH radicals are the main active species for the MB degradation. The high visible-light photocatalytic activity was attributed to low recombination of the photo-generated electrons and holes which originated from the synergistic effect of the co-doped ions and the heterostructure.

  9. 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...

  10. Silicon carbide coated with TiO2 with enhanced cobalt active phase dispersion for Fischer-Tropsch synthesis.

    Science.gov (United States)

    Liu, Yuefeng; Florea, Ileana; Ersen, Ovidiu; Pham-Huu, Cuong; Meny, Christian

    2015-01-04

    The introduction of a thin layer of TiO2 on β-SiC allows a significant improvement of the cobalt dispersion. This catalyst exhibits an excellent and stable catalytic activity for the Fischer-Tropsch synthesis (FTS) with high C5+ selectivity, which contributes to the development of a new active catalyst family in the gas-to-liquid process.

  11. Effect of Tb2O3 additive on structure of anatase and photocatalytic activity of TiO2/(O'+β')-Sialon multi-phase ceramics

    Institute of Scientific and Technical Information of China (English)

    YANG Jian; PAN Limei; XUE Xiangxin; WANG Mei; QIU Tai

    2009-01-01

    Effect of rare earth oxide Tb2O3 additive on transformation behavior and grain growth of anatase and photocatalytic activity for TiO2/(O'+β')-Sialon multi-phase ceramic was investigated and the mechanism was discussed. X-ray diffractometer (XRD) was employed for the analysis of phase composition, grain size and lattice parameters of anatase. Photocatalyfic activity of the composites was investigated through its photocatalytic degradation to methylene blue (MB) solution. The results showed that Tb2O3 significantly inhibited the transfor-marion process, which displayed an appreciably intensified effect with increasing Tb203 content. It could be attributed to the coaction of the active and passive influence mechanisms. For Tb3+ entering TiO2 lattice, replacing Ti4+ accelerated the transformation, whereas the lattice distortion caused by it was unfavorable for the process. On the other hand, the redox reaction between Tb3+ and TiO2 as well as the Tb2O3 deposited on the surface of TiO2 inhibited the transformation. The addition of Tb2O3 effectively restrained the grain growth of TiO2 and the effect became significant with the increase of its content. With the increase of Tb2O3 addition, the photocatalytic activity of the catalysts in-creased and then dropped after reaching the maximum at about 2%. The action mechanism of Tb2O3 could be attributed to its optical proper-ties and its effect on phase transformation, grain growth and crystal structure of TiO2.

  12. 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.

  13. 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.

  14. Gait phase detection and discrimination between walking-jogging activities using hidden Markov models applied to foot motion data from a gyroscope.

    Science.gov (United States)

    Mannini, Andrea; Sabatini, Angelo Maria

    2012-09-01

    In this paper we present a classifier based on a hidden Markov model (HMM) that was applied to a gait treadmill dataset for gait phase detection and walking/jogging discrimination. The gait events foot strike, foot flat, heel off, toe off were detected using a uni-axial gyroscope that measured the foot instep angular velocity in the sagittal plane. Walking/jogging activities were discriminated by processing gyroscope data from each detected stride. Supervised learning of the classifier was undertaken using reference data from an optical motion analysis system. Remarkably good generalization properties were achieved across tested subjects and gait speeds. Sensitivity and specificity of gait phase detection exceeded 94% and 98%, respectively, with timing errors that were less than 20 ms, on average; the accuracy of walking/jogging discrimination was approximately 99%.

  15. Lattice strain alteration and activation energy of phase transformation of TiO2 nanorods doped with silver and iron oxides

    Science.gov (United States)

    Riazian, M.

    2013-10-01

    TiO2 nanorods are synthesized by a thermal corrosion. In present work, synthesis of TiO2 nanorods in anatase, rutile and Ti8O15 phases, TiO2 nanorods embedded with silver and iron oxides as dopant by using the sol-gel method and alkaline corrosion are reported. The morphologies and crystal structures of TiO2 nanorods are characterized by use of field emission scanning electron microscopy, atomic force microscopy and X-ray diffractometer techniques. The obtained results illustrate an aggregative structure at high calcined temperatures with production of spherical particles. The effects of chemical compositions and calcined temperatures on surface topography and crystallization of phases are studied. Moreover, activation energy of nanoparticles formation in pure and doped state are calculated during thermal treatment.

  16. 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 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......, growth phase and growth rate regulation under aerobic conditions was maintained, while ArcA-dependent anaerobic induction was greatly diminished. Judged by two-dimensional gel electrophoresis, the appY promoter fragment exhibits the features characteristic of curved DNA. Gel retardation assays showed...

  17. 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.

  18. Female ovarian cycle phase affects the timing of male sexual activity in free-ranging Barbary macaques (Macaca sylvanus) of Gibraltar.

    Science.gov (United States)

    Heistermann, Michael; Brauch, Katrin; Möhle, Ulrike; Pfefferle, Dana; Dittami, John; Hodges, Keith

    2008-01-01

    Although all macaques have a multimale multifemale mating system, the degree of promiscuity shown by the Barbary macaque is considered to be extreme in terms of both mating frequency and number of mating partners. How mating activity is distributed throughout the female menstrual cycle and whether or not copulations are concentrated around the fertile phase as in other members of the genus is, however, not known. To examine this, we collected data on rates of copulation throughout 29 ovarian cycles from 13 free-ranging females of the Gibraltar Barbary macaque population and related them to the time of ovulation and the female fertile phase as determined from fecal hormone analysis. In addition, patterns of male inspection of females and time spent in consortship, both indicators of female attractivity, were also analyzed. The results indicate that both mating behavior and female attractivity vary predictably with ovarian cycle stage. Rates of copulation were found to increase toward the time of ovulation, with a distinct peak of ejaculatory (but not non-ejaculatory) copulations occurring in the fertile phase. Additionally, we show that frequency of inspection of females by males and time spent in consortship were also highest during the fertile phase and that ejaculatory copulations and male pericopulatory behaviors were significantly correlated with levels of female sex hormones. Our findings indicate that the Barbary macaque shows a mating pattern during the cycle similar to that described for other members of the genus. More importantly, however, our study provides clear evidence that despite an extreme degree of promiscuity Barbary macaque males concentrate their reproductive effort to the fertile phase, implying that they are able to discern this period and that thus timing of ovulation is not concealed from them. Estrogen-related cues appear to be involved in the process of recognition of female reproductive status by males, but the exact nature of these cues

  19. Bioassay-guided fractionation of Melastoma malabathricum Linn. leaf solid phase extraction fraction and its anticoagulant activity.

    Science.gov (United States)

    Khoo, Li Teng; Abdullah, Janna Ong; Abas, Faridah; Tohit, Eusni Rahayu Mohd; Hamid, Muhajir

    2015-02-24

    The aims of this study were to examine the bioactive component(s) responsible for the anticoagulant activity of M. malabathricum Linn. leaf hot water crude extract via bioassay-guided fractionation and to evaluate the effect of bioactive component(s) on the intrinsic blood coagulation pathway. The active anticoagulant fraction of F3 was subjected to a series of chromatographic separation and spectroscopic analyses. Furthermore, the effect of the bioactive component(s) on the intrinsic blood coagulation pathway was studied through immediate and time incubation mixing studies. Through Activated Partial Thromboplastin Time (APTT) assay-guided fractionation, Subfraction B was considered the most potent anticoagulant fraction. Characterisation of Subfraction B indicated that anticoagulant activity could partly be due to the presence of cinnamic acid and a cinnamic acid derivative. APTT assays for both the immediate and time incubation mixing were corrected back into normal clotting time range (35.4-56.3 s). In conclusion, cinnamic acid and cinnamic acid derivative from Subfraction B were the first such compounds to be discovered from M. malabathricum Linn. leaf hot water crude extract that possess anticoagulant activity. This active anticoagulant Subfraction B prolonged blood clotting time by causing factor(s) deficiency in the intrinsic blood coagulation pathway.

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. Association between CISH polymorphisms and spontaneous clearance of hepatitis B virus in hepatitis B extracellular antigen-positive patients during immune active phase

    Institute of Scientific and Technical Information of China (English)

    Song Guangjun; Rao Huiying; Feng Bo; Wei Lai

    2014-01-01

    Background Some hepatitis B extracellular antigen (HBeAg)-positive chronic hepatitis B (CHB) patients in their immune active phase can clear the virus spontaneously and enter into an inactive hepatitis B virus (HBV) carrier state,indicating a benign prognosis.In this study,the association between cytokine-inducibie SRC homology 2 domain protein (C/SH) gene polymorphisms at-292 (rs414171) and the spontaneous clearance of HBV in HBeAg-positive CHB patients in immune the active phase was investigated.Methods Seventy HBeAg-positive CHB patients in the immune active phase were followed up for 76 weeks without antiviral therapy.The alanine transaminase,aspartate transaminase,HBV DNA,HBeAg and hepatitis B extracellular antibody levels were tested regularly.At week 76,27 patients were classified into group A (HBV DNA level below 2 104 IU/ml and the value of HBeAg declined below 10% of the baseline at week 76),and 43 patients were classified into group B (HBV DNA level higher than 2×104 IU/ml or the value of HBeAg did not decline substantially at week 76).CISH (rs414171) polymorphisms were also tested using the iPLEX system.Results The HBV DNA levels at week 12 were significantly greater in group B compared with group A (group A:(6.87±1.40) log10IU/ml; group B:(7.61±1.38) log10IU/ml,P=0.034) and the HBeAg values were greater in group B at week 28 compared with group A (P=0.001).The differences in HBV DNA and HBeAg values increased between the groups over time.Sixteen patients in group A and 11 in group B were genotype AA.Those with genotype AT or TT included 11 in group A and 31 in group B (AA vs.AT and TT,odds ratio 4.10 (95% confidence interval:1.462-11.491),P=0.006).Conclusion CISH gene polymorphisms at-292 (rs414171) are associated with HBV clearance in HBeAg-positive CHB patients in the immune active phase,and AA is a favorable genotype for this effect.

  5. 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.

  6. 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

    . 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......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...

  7. Evidence for the Active Phase of Heterogeneous Catalysts through In Situ Reaction Product Imaging and Multiscale Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Matera, S.; Blomberg, S.; Hoffmann, M. J.; Zetterberg, J.; Gustafson, J.; Lundgren, E.; Reuter, K.

    2015-06-17

    We use multiscale modeling to analyze laser-induced fluorescence (LIF) measurements of the CO oxidation reaction over Pd(100) at near-ambient reaction conditions. Integrating density functional theory-based kinetic Monte Carlo simulations of the active catalyst into fluid-dynamical simulations of the mass transport inside the reactor chamber, we calculate the reaction product concentration directly above the catalyst surface. Comparing corresponding data calculated for different surface models against the measured LIF signals, we can discriminate the one that predominantly actuates the experimentally measured catalytic activity. For the probed CO oxidation reaction conditions, the experimental activity is due to pristine Pd(100) possibly coexisting with other (oxidic) domains on the surface.

  8. 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

    loading of the power devices. However, its feasibility is challenged by the associated energy losses. An increase of the inverter lifetime and a reduction of the energy yield can alter the cost of energy, demanding an optimization of the power limitation. Therefore, aiming at minimizing the Levelized Cost...... 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...

  9. Water O-H bond activation by gas-phase plutonium atoms: reaction mechanisms and ab initio molecular dynamics study.

    Science.gov (United States)

    Li, Peng; Niu, Wenxia; Gao, Tao; Wang, Hongyan

    2014-10-06

    A thorough description of the reaction mechanisms, taking into account different possible spin states, offers insights into the gas-phase reaction of plutonium atoms with water. Two possible reactions (isomerization and dehydrogenation) are presented. These reactions are found to be exothermic, with the best thermochemical conditions observed for the dehydrogenation reaction at around 23.5 kcal mol(-1). The nature of the chemical-bonding evolution along the reaction pathways are investigated by employing various methods including electron localization function, atoms in molecules, and Mayer bond order. Total, partial, and overlap population density of state diagrams and analyses are also presented. Reaction rates at elevated temperatures (T=298-2 000 K) are calculated by using variational transition-state theory with one-dimensional tunneling effects. In dynamics simulations, only the dehydrogenation reaction is observed, and found to be in good agreement with experimental values.

  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. 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.

  12. In vitro biomonitoring in polar extracts of solid phase matrices reveals the presence of unknown compounds with estrogenic activity

    NARCIS (Netherlands)

    Legler, J.; Leonards, P.E.G.; Spenkelink, A.; Murk, A.J.

    2003-01-01

    Determination of estrogenic activity has so far mainly concentrated on the assessment of compounds in surface water and effluent. This study is one of the first to biomonitor (xeno-)estrogens in sediment, suspended particulate matter and aquatic organisms. The relatively polar acetone extracts from

  13. Pre-Launch phase 2 rehearsal of the calibration and validation of soil moisture active passive (SMAP) geophysical data products

    Science.gov (United States)

    NASA’s Soil Moisture Active Passive (SMAP) Mission is scheduled for launch in early November 2014. The objective of the mission is global mapping of soil moisture and landscape freeze/thaw state. SMAP utilizes L-band radar and radiometer measurements sharing a rotating 6-meter mesh reflector antenna...

  14. 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...

  15. 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...

  16. 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.

  17. 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.

  18. 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

  19. 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

  20. Celecoxib treatment does not alter recruitment and activation of osteoclasts in the initial phase of experimental tooth movement

    Directory of Open Access Journals (Sweden)

    E.P. Carvalho-Filho

    2012-10-01

    Full Text Available 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 (carboxymethylcellulose 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

  1. Identification of Inhibitory Premotor Interneurons Activated at a Late Phase in a Motor Cycle during Drosophila Larval Locomotion.

    Science.gov (United States)

    Itakura, Yuki; Kohsaka, Hiroshi; Ohyama, Tomoko; Zlatic, Marta; Pulver, Stefan R; Nose, Akinao

    2015-01-01

    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 behind that of

  2. A shirt containing multistage phase change material and active cooling components was associated with increased exercise capacity in a hot, humid environment.

    Science.gov (United States)

    McFarlin, Brian K; Henning, Andrea L; Venable, Adam S; Williams, Randall R; Best Sampson, Jill N

    2016-08-01

    Recent advances in clothing design include the incorporation of phase change materials (PCM) and other active cooling components (ACC) to provide better body heat dissipation. The purpose of this study was to determine the effect of wearing a shirt containing multistage PCM/ACC on exercise capacity at low (5.0), moderate-high (7.5) and extreme (9.0) levels of the physiological strain index (PSI). Fourteen individuals tested two shirts (control vs. cooling) during 45-min of interval running in a hot, humid (35 ± 1 °C; 55 ± 6% RH) environment. The cooling shirt resulted in an 8% improvement in exercise capacity at a PSI of 7.5 (p active cooling components.

  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. A randomized, placebo controlled, double masked phase IB study evaluating the safety and antiviral activity of aprepitant, a neurokinin-1 receptor antagonist in HIV-1 infected adults.

    Directory of Open Access Journals (Sweden)

    Pablo Tebas

    Full Text Available BACKGROUND: Neurokinin-1 receptor (NK1R antagonists have anti-HIV activity in monocyte-derived macrophages, decrease CCR5 expression and improve natural killer cell function ex vivo. Aprepitant is a NK1R antagonist approved by FDA as an antiemetic. METHODS: We conducted a phase IB randomized, placebo controlled, double masked study to evaluate the safety, antiviral activity, pharmacokinetics and immune-modulatory effects of aprepitant in HIV-infected adults not receiving antiretroviral therapy, with CD4+ cell count ≥350 cells/mm(3 and plasma viral load ≥2,000 copies/ml. Subjects were stratified by viral load (< vs. ≥20,000 copies/ml and randomized within each stratum to receive aprepitant at 125 mg QD(Low, or 250 mg QD(High, or placebo(PL for 14 days, and followed for 42 days. RESULTS: Thirty subjects were randomized and 27 completed treatment (9, 8, 10 subjects in 125 (Low, 250 (High, and PL groups. 63% were male; 37% white; mean (SD age 43 (9.3 years. Geometric mean baseline viral load (copies/ml for Low, High, and PL was 15,709, 33,013, and 19,450, respectively. Mean (95%CI change in log10 viral load at day 14 for Low, High, and PL was -0.02(-0.24,+0.20, -0.05(-0.21,+0.10, and +0.04(-0.08,+0.16, respectively. The number of subjects with AEs was 4(44.4%, 5(62.5%, and 1(10% for Low, High, and PL. No Grade 4 AEs occurred. CONCLUSIONS: Adverse events of aprepitant were more common in the treated groups. At the dose used in this two-week phase IB study, aprepitant showed biological activity, but no significant antiviral activity. TRIAL REGISTRATION: ClinicalTrials.gov NCT00428519.

  5. Selective synthesis and visible-light photocatalytic activities of BiVO{sub 4} with different crystalline phases

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Xi [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China); Ai Zhihui [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China)]. E-mail: jennifer.ai@mail.ccnu.edu.cn; Jia Falong [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China); Zhang Lizhi [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China)]. E-mail: zhanglz@mail.ccnu.edu.cn; Fan Xiaoxing [Ecomaterials and Renewable Energy Research Center (ERERC), Department of Physics, Nanjing University, Nanjing 210093 (China); Zou Zhigang [Ecomaterials and Renewable Energy Research Center (ERERC), Department of Physics, Nanjing University, Nanjing 210093 (China)

    2007-05-15

    Tetragonal and monoclinic bismuth vanadate (BiVO{sub 4}) powders were selectively synthesized by aqueous processes. The characterizations of the as-prepared BiVO{sub 4} powders were carried out by X-ray diffraction, nitrogen adsorption, scanning electron microscopy and UV-vis diffuse reflectance spectroscopy. The photocatalytic activities of different BiVO{sub 4} samples were determined by degradation of methylene blue solution under visible-light irradiation ({lambda} > 420 nm) and compared with that of TiO{sub 2} (Degussa P25). The band gaps of the as-prepared BiVO{sub 4} were determined from UV-vis diffuse reflectance spectra. It was found that monoclinic BiVO{sub 4} with a band gap of 2.34 eV showed higher photocatalytic activity than that of tetragonal BiVO{sub 4} with a band gap of 3.11 eV.

  6. Activity-guided isolation of constituents of Tephrosia purpurea with the potential to induce the phase II enzyme, quinone reductase.

    Science.gov (United States)

    Chang, L C; Gerhäuser, C; Song, L; Farnsworth, N R; Pezzuto, J M; Kinghorn, A D

    1997-09-01

    An isoflavone, 7,4'-dihydroxy-3',5'-dimethoxyisoflavone (1), and a chalcone, (+)-tephropurpurin (2), both novel compounds, as well as six constituents of known structure, (+)-purpurin (3), pongamol (4), lanceolatin B (5), (-)-maackiain (6), (-)-3-hydroxy-4-methoxy-8,9-methylene-dioxypterocarpan (7), and (-)-medicarpin (8), were obtained as active compounds from Tephrosia purpurea, using a bioassay based on the induction of quinone reductase (QR) activity with cultured Hepa 1c1c7 mouse hepatoma cells. Additionally, three inactive compounds of known structure, 3'-methoxydaidzein, desmoxyphyllin B, and 3,9-dihydroxy-8-methoxycoumestan, were isolated and identified. The structure elucidation of compounds 1 and 2 was carried out by spectral data interpretation.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Efficiency Considerations and Application Limits of Single-Phase Active Power Filter with Converters for Photoenergy Applications

    Directory of Open Access Journals (Sweden)

    Saša Sladić

    2011-01-01

    Full Text Available A new way of connecting PV sources to adaptive voltage active power filter (AV APF has been compared with classic approach including active power filter (APF. In standard active power filter applications a relatively high DC link voltage (500 V or even more with a buck converter or lower voltage (approx. 100 V with boost converter can be used. These two converters appear also in adaptive voltage circuit of AV APF, but in this case it is possible to achieve many different connections of DC source. Benefit of this approach is that the same circuit is used for improving switching conditions in APF and for connection of solar cells. It appears that these two functions support each other and a large variety of DC voltages and currents can be connected to AC mains. Experimental results confirm expectations of increased energy transfer from additional DC source to network, especially for DC voltages being lower than DC link voltage.

  14. Assessments of fatigue and disease activity in patients with systemic lupus erythematosus enrolled in the Phase 2 clinical trial with blisibimod.

    Science.gov (United States)

    Petri, M A; Martin, R S; Scheinberg, M A; Furie, R A

    2017-01-01

    This report evaluates the effects of blisibimod (A-623, AMG 623), a potent and selective inhibitor of B-cell activating factor (BAFF), on patient-reported fatigue and disease activity in the Phase 2b PEARL-SC clinical trial in patients with systemic lupus erythematosus (SLE). A total of 547 individuals who met the American College of Rheumatology (ACR) classification criteria for SLE, were positive for anti-double-stranded DNA or antinuclear antibodies, and had a Safety of Estrogens in Lupus Erythematosus National Assessment-Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) score ≥6 at baseline, were randomized to receive placebo or blisibimod for at least 24 weeks. Patient self-reported fatigue was evaluated using the Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue scale, and disease activity was evaluated using Physician's Global Assessment, SELENA-SLEDAI, and British Isles Lupus Assessment Group Score. Statistically significant improvements in FACIT-Fatigue score were observed among individuals randomized to blisibimod, especially in the 200 mg QW group where favorable effects on disease activity with blisibimod compared to placebo were observed as early as Week 8. The mean improvement from baseline of 6.9 points at Week 24, compared with 4.4 points with placebo, met the criteria for minimal clinically important improvement difference defined for patients with SLE. Despite concomitant improvements in FACIT-Fatigue, SLE Responder Index (SRI) and SLE biomarkers (reported previously), FACIT-Fatigue score correlated only weakly with disease activity. While poor correlation between fatigue and disease activity is not new, the observation that correlation remains poor despite concurrent population improvements in disease and fatigue brings a new facet to our understanding of SLE.

  15. Activity and safety of pegylated liposomal doxorubicin,5-fluorouracil and folinic acid in inoperable hepatocellular carcinoma: A phase Ⅱ study

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To improve the results of New therapeutic strategies in hepatocellular carcinoma (HCC). We have conducted a phase Ⅱ study with pegylated liposomal doxorubicin (PLD), 5-fluorouracil (5FU) and folinic acid (FA).METHODS: Thirty-one patients with hystologically-confirmed, inoperable HCC, received combination chemotherapy with PLD 25 mg/mq on d 1, 5FU 1200 mg/mq in 48 h continuous infusion, and oral FA 30 mg on d 1 and 2 every 3 wk until disease progression or intolerable toxicity.RESULTS: The median age was 65 years (range 41-82) and 28 patients were hepatitis C virus seropositive (90%).The majority of patients were Child-Pugh Class B (55%).Two patients showed a partial response (PR), and 16 had stable disease (SD). With a median follow-up of 14 mo, the median time to progression of all evaluable patients was 4 mo (95% CI 1.7-7). Median overall survival was 9 mo (95% CI 3-24 mo). After 1 year, 9 of 18 PR/SD patients were alive. Chemotherapy was well tolerated.CONCLUSION: PLD/FU/FA combination seems capable of achieving durable stabilization of HCC. The manageable toxicity supports a role for combination with other anticancer agents.

  16. Recovery Efficiency Test Project: Phase 1, Activity report. Volume 1: Site selection, drill plan preparation, drilling, logging, and coring operations

    Energy Technology Data Exchange (ETDEWEB)

    Overbey, W.K. Jr.; Carden, R.S.; Kirr, J.N.

    1987-04-01

    The recovery Efficiency Test well project addressed a number of technical issues. The primary objective was to determine the increased efficiency gas recovery of a long horizontal wellbore over that of a vertical wellbore and, more specifically, what improvements can be expected from inducing multiple hydraulic fractures from such a wellbore. BDM corporation located, planned, and drilled a long radius turn horizontal well in the Devonian shale Lower Huron section in Wayne County, West Virginia, demonstrating that state-of-the-art technology is capable of drilling such wells. BDM successfully tested drilling, coring, and logging in a horizontal well using air as the circulating medium; conducted reservoir modeling studies to protect flow rates and reserves in advance of drilling operations; observed two phase flow conditions in the wellbore not observed previously; cored a fracture zone which produced gas; observed that fractures in the core and the wellbore were not systematically spaced (varied from 5 to 68 feet in different parts of the wellbore); observed that highest gas show rates reported by the mud logger corresponded to zone with lowest fracture spacing (five feet) or high fracture frequency. Four and one-half inch casting was successfully installed in the borehole and was equipped to isolate the horizontal section into eight (8) zones for future testing and stimulation operations. 6 refs., 48 figs., 10 tabs.

  17. Silicide induced surface defects in FePt nanoparticle fcc-to-fct thermally activated phase transition

    Science.gov (United States)

    Chen, Shu; Lee, Stephen L.; André, Pascal

    2016-11-01

    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 treatments on the magnetic properties. In this study, we focus on the impact of silica shells often used in strategies aiming at overcoming MnP coalescence during the thermal annealing. While we show that this shell does prevent sintering, and that fcc-to-fct conversion does occur, we also reveal the formation of silicide, which can prevent the stronger magnetic properties of fct-FePt MnPs from being fully realised. This report therefore sheds lights on poorly investigated and understood interfacial phenomena occurring during the thermal annealing of MnPs and, by doing so, also highlights the benefits of developing new strategies to avoid silicide formation.

  18. 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.

  19. Platelet adhesion, contact phase coagulation activation, and C5a generation of polyethylene glycol acid-grafted high flux cellulosic membrane with varieties of grafting amounts.

    Science.gov (United States)

    Fushimi, F; Nakayama, M; Nishimura, K; Hiyoshi, T

    1998-10-01

    Grafting of polyethylene glycol chains onto cellulosic membrane can be expected to reduce the interaction between blood (plasma protein and cells) and the membrane surface. Alkylether carboxylic acid (PEG acid) grafted high flux cellulosic membranes for hemodialysis, in which the polyethylene glycol chain bears an alkyl group at one side and a carboxyl group at the other side, have been developed and evaluated. PEG acid-grafted high flux cellulosic membranes with various grafting amounts have been compared with respect to platelet adhesion, the contact phase of blood coagulation, and complement activation in vitro. A new method of quantitating platelet adhesion on hollow-fiber membrane surfaces has been developed, which is based on the determination of lactate dehydrogenase (LDH) activity after lysis of the adhered platelets. PEG acid-grafted high flux cellulosic membranes showed reduced platelet adhesion and complement activation effects in grafting amounts of 200 ppm or higher without detecting adverse effects up to grafting amounts of 850 ppm. The platelet adhesion of a PEG acid-grafted cellulosic membrane depends on both the flux and grafting amounts of the membrane. It is concluded that the grafting of PEG acid onto a cellulosic membrane improves its biocompatibility as evaluated in terms of platelet adhesion, complement activation, and thrombogenicity.

  20. Complement and Reactants of Acute Phase of Inflammation in the Processes of Functional Activity of Non-Specific Resistance and Immunoregulation.

    Science.gov (United States)

    Nazarov, Peter G.

    1999-10-01

    Complement system is a family comprising of 20 plasma and membrane proteins, acting in concord by cascade principle. The investigators display great interest to C4b-binding protein (C4bp) which is the main regulatory protein of complement system, regulating of C3 convertase activity in classical way of complement activation. The major regulatory function of C4bp is related to its interaction with activated form of the forth complement component, C4b. C4bp may also interact with one of pentraxins, serum amyloid P component (SAP) that inhibits complement-regulatory functions of C4bp. C4bp forms tight complexes with protein S and SAP. Pentraxin family (proteins with five-ray symmetry, such as C-reactive protein and SAP) became more numerous. Protein PTX3, synthesized by endothelial cells, macrophages and leukocytes, and considered to be local regulator of reaction of non-specific resistance in tissues; serum acute phase protein TSG-14; neuronal pentraxin - protein of cerebellum, hippocampus and brain cortex neurons, binding typoxin of snake venom; Narp (neuronal activity-regulated pentraxin) protein; apexin, acrosomal protein of spermatozoa; female hamster protein; pentraxin XL-PXN1 from Xenopus laevis - are all examples of new pentraxins. Pro-inflammatory cytokines, IL-1 and IL-6, may induce expression of pentraxin genes. Pentraxins are closely integrated not only to non-specific resistance, but to the system of immunoregulation and take part in its key events.

  1. Activated kinetics of the Crystalline to Nematic (K-N) and Nematic to Isotropic (N-I) phase transitions of Pentylcyanobiphenyl (5CB) liquid crystal

    Science.gov (United States)

    Sharma, Dipti

    2011-04-01

    Activated kinetics of the crystalline to Nematic (K-N) and the Nematic to Isotropic (N-I) phase transitions of the Pentylcyanobiphenyl (5CB) liquid crystal are discussed here. A kinetic comparison of the same types of transitions of other family member with higher number of carbon atoms i.e. Octylcyanobiphenyl (8CB) are also made to see the difference between the kinetic behavior of the above two transitions of the liquid crystals. Experiments were performed using high resolution calorimetric technique for heating and cooling runs. Two different scans i.e. Temperature scans and Rate scans were performed for 5CB and 8CB from 280 to 333 K at various rates to get the detailed behavior of the transitions. As a result, Double activation was observed for 5CB for two heating rate regimes whereas 8CB indicated single activation only. The 5CB has smaller enthalpy and entropy of the transitions and needs larger activation than 8CB. This kinetic change can be explained in terms of the length scale and mobility of the liquid crystal molecules.

  2. 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

    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...... 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...

  3. Major Neutrophilia Observed in Acute Phase of Human Leptospirosis Is Not Associated with Increased Expression of Granulocyte Cell Activation Markers

    Science.gov (United States)

    Raffray, Loic; Giry, Claude; Vandroux, David; Kuli, Barbara; Randrianjohany, Andry; Pequin, Anne-Marie; Renou, Frédéric; Jaffar-Bandjee, Marie-Christine; Gasque, Philippe

    2016-01-01

    It has long been known that pathogenic Leptospira can mobilize the immune system but the specific contribution of neutrophils to control the infectious challenge remains to be clarified. We herein analyzed the phenotype of circulating neutrophils of patients with leptospirosis and healthy controls for the expression of toll-like receptor (TLR) type 2 (TLR2, to sense the leptospiral LPS) and several activation markers: interleukin 8 chemokine receptor CD182 (CXCR2), CD11b of the integrin/opsonin complement receptor type 3 (CR3) and CD15 (ligand of the selectin). The plasmatic level of the main CD182 ligand, interleukin 8 (CXCL8), was measured by ELISA. Hospitalized leptospirosis cases showed marked neutrophilia, particularly in the most severe cases. Interestingly, TLR2 was significantly increased in leptospirosis but identical levels of CD182 and CD11b were detected when compared to controls. CD15 was significantly decreased on neutrophils in leptospirosis but returned to normal within 1 month. Basal levels of IL-8 were measured in control subjects and were not increased in leptospirosis cases at the initial stage of the disease. In conclusion, we observed that neutrophils failed to regulate the expression of several of the receptors involved in cell activation and recruitment. This study further emphasizes the paradigm that neutrophils may be impaired in their overall capacity to thwart bacterial infection in leptospirosis patients. PMID:27802348

  4. 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.

  5. Kinetic modeling of liquid-phase adsorption of Congo red dye using guava leaf-based activated carbon

    Science.gov (United States)

    Ojedokun, Adedamola Titi; Bello, Olugbenga Solomon

    2016-02-01

    Guava leaf, a waste material, was treated and activated to prepare adsorbent. The adsorbent was characterized using Scanning Electron Microscopy (SEM), Fourier Transform Infra Red (FTIR) and Energy-Dispersive X-ray (EDX) techniques. The carbonaceous adsorbent prepared from guava leaf had appreciable carbon content (86.84 %). The adsorption of Congo red dye onto guava leaf-based activated carbon (GLAC) was studied in this research. Experimental data were analyzed by four different model equations: Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherms and it was found to fit Freundlich equation most. Adsorption rate constants were determined using pseudo-first-order, pseudo-second-order, Elovich and intraparticle diffusion model equations. The results clearly showed that the adsorption of CR dye onto GLAC followed pseudo-second-order kinetic model. Intraparticle diffusion was involved in the adsorption process. The mean energy of adsorption calculated from D-R isotherm confirmed the involvement of physical adsorption. Thermodynamic parameters were obtained and it was found that the adsorption of CR dye onto GLAC was an exothermic and spontaneous process at the temperatures under investigation. The maximum adsorption of CR dye by GLAC was found to be 47.62 mg/g. The study shows that GLAC is an effective adsorbent for the adsorption of CR dye from aqueous solution.

  6. 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.

  7. Geometric phases in physics

    CERN Document Server

    Shapere, Alfred D

    1989-01-01

    During the last few years, considerable interest has been focused on the phase that waves accumulate when the equations governing the waves vary slowly. The recent flurry of activity was set off by a paper by Michael Berry, where it was found that the adiabatic evolution of energy eigenfunctions in quantum mechanics contains a phase of geometric origin (now known as 'Berry's phase') in addition to the usual dynamical phase derived from Schrödinger's equation. This observation, though basically elementary, seems to be quite profound. Phases with similar mathematical origins have been identified

  8. Canakinumab treatment for patients with active recurrent or chronic TNF receptor-associated periodic syndrome (TRAPS): an open-label, phase II study

    Science.gov (United States)

    Gattorno, Marco; Obici, Laura; Cattalini, Marco; Tormey, Vincent; Abrams, Ken; Davis, Nicole; Speziale, Antonio; Bhansali, Suraj G; Martini, Alberto; Lachmann, Helen J

    2017-01-01

    Objective To evaluate the efficacy of canakinumab, a high-affinity human monoclonal anti-interleukin-1β antibody, in inducing complete or almost complete responses in patients with active tumour necrosis factor receptor-associated periodic syndrome (TRAPS). Methods Twenty patients (aged 7–78 years) with active recurrent or chronic TRAPS were treated with canakinumab 150 mg every 4 weeks for 4 months (2 mg/kg for those ≤40 kg) in this open-label, proof-of-concept, phase II study. Canakinumab was then withdrawn for up to 5 months, with reintroduction on relapse, and 4 weekly administration (subsequently increased to every 8 weeks) for 24 months. The primary efficacy variable was the proportion of patients achieving complete or almost complete response at day 15, defined as clinical remission (Physician's Global Assessment score ≤1) and full or partial serological remission. Results Nineteen patients (19/20, 95%; 95% CI 75.1% to 99.9%) achieved the primary efficacy variable. Responses to canakinumab occurred rapidly; median time to clinical remission 4 days (95% CI 3 to 8 days). All patients relapsed after canakinumab was withdrawn; median time to relapse 91.5 days (95% CI 65 to 117 days). On reintroduction of canakinumab, clinical and serological responses were similar to those seen during the first phase, and were sustained throughout treatment. Canakinumab was well tolerated and clinical responses were accompanied by rapid and sustained improvement in health-related quality of life. Weight normalised pharmacokinetics of canakinumab, although limited, appeared to be consistent with historical canakinumab data. Conclusions Canakinumab induces rapid disease control in patients with active TRAPS, and clinical benefits are sustained during long-term treatment. Trial registration number NCT01242813; Results. PMID:27269295

  9. 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)

  10. Notch1 signaling regulates the proliferation and self-renewal of human dental follicle cells by modulating the G1/S phase transition and telomerase activity.

    Directory of Open Access Journals (Sweden)

    Xuepeng Chen

    Full Text Available Multipotent human dental follicle cells (HDFCs have been intensively studied in periodontal regeneration research, yet the role of Notch1 in HDFCs has not been fully understood. The aim of the current study is to explore the role of Notch1 signaling in HDFCs self-renewal and proliferation. HDFCs were obtained from the extracted wisdom teeth from adolescent patients. Regulation of Notch1 signaling in the HDFCs was achieved by overexpressing the exogenous intracellular domain of Notch1 (ICN1 or silencing Notch1 by shRNA. The regulatory effects of Notch1 on HDFC proliferation, cell cycle distribution and the expression of cell cycle regulators were investigated through various molecular technologies, including plasmid construction, retrovirus preparation and infection, qRT-PCR, western blot, RBP-Jk luciferase reporter and cell proliferation assay. Our data clearly show that constitutively activation of Notch1 stimulates the HDFCs proliferation while inhibition of the Notch1 suppresses their proliferation in vitro. In addition, the HDFCs proliferation is associated with the increased expression of cell cycle regulators, e.g. cyclin D1, cyclin D2, cyclin D3, cyclin E1, CDK2, CDK4, CDK6, and SKP2 and the decreased expression of p27 (kip1. Moreover, our data show that the G1/S phase transition (indicating proliferation and telomerase activity (indicating self-renewal can be enhanced by overexpression of ICN1 but halted by inhibition of Notch1. Together, the current study provides evidence for the first time that Notch1 signaling regulates the proliferation and self-renewal capacity of HDFCs through modulation of the G1/S phase transition and the telomerase activity.

  11. Activation of type I interferon signaling in the parotid and exorbital lachrymal glands during the acute phase of encephalomyocarditis (EMC) virus infection in mice.

    Science.gov (United States)

    Ohguchi, Atsuko; Yamauchi, Hirofumi; Doi, Kunio; Nakayama, Hiroyuki

    2016-06-01

    The present study was carried out to clarify the mechanisms of EMC virus-induced sialodacryoadenitis in mice during the acute phase infection focusing on the activation of type I interferon (IFN) signaling in the parotid and exorbital lachrymal glands. In the parotid gland, a few apoptotic acinar cells were detected at 2days post inoculation (DPI). The ratio of apoptotic acinar cells increased at 3 and 4DPI. On the other hand, in the exorbital lachrymal gland, apoptosis of acinar cells and infiltration of inflammatory cells mainly composed of mononuclear cells started at 3DPI, and prominent acinar cell damage developed at 4DPI. Viral RNA was detected at 3 and 4DPI in both glands and the expression level was higher in the exorbital lachrymal gland than in the parotid gland. The up-regulation of IFN-stimulated genes (ISGs), such as Irf7, Pkr and Oas, was quickly induced at 2DPI in the parotid gland, and this probably contributed to suppress viral replication and to eliminate affected cells by apoptosis. In the exorbital lachrymal gland, the expression levels of ISGs mRNAs were not elevated at 2DPI, suggesting no induction of an effective anti-viral response such as apoptosis at this time point. In the exorbital lachrymal gland, the mRNA expression of IFN beta and IFN alpha (type I IFNs) was weak- to strong-positive at 1DPI, and became negative at 2DPI. The weak- to strong-positive expression of IFNs at 1DPI is likely related to the abrupt viral replication and pathological changes in the exorbital lachrymal gland through activating the negative feedback regulation that depressed the IFN signaling cascade at 2DPI. In conclusion, the present study showed the changes in factors involved in the activation of type I IFN signaling cascade in the parotid and exorbital lachrymal glands and their differences between the two glands during the acute phase of EMC virus infection in mice.

  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. Self-commissioning notch filter for active damping in three phase LCL-filter based grid converters

    DEFF Research Database (Denmark)

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

    2013-01-01

    challenge the LCL-filter stability. Active damping by using a notch filter on the reference voltage for the modulator is simple to implement and does not require additional sensors. With the notch frequency tuned for the resonant frequency the voltage reference does not contain any component susceptible...... of exciting the LCL-filter. However, the notch filter tuning requires considerable design effort and the variations in the resonance frequency limit the LCL-filter robustness. This paper proposes a simple tuning procedure for the notch filter that results in proper robustness. In order to cope with the grid...... inductance variations it is proposed to estimate the resonance frequency by means of Fourier analysis. The Goertzel algorithm, instead of the FFT, is used to reduce the calculation and memory requirements. Thus, the proposed self-commissioning notch filter results robust and consumes little computational...

  14. [Analysis of the effect of p