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Sample records for dominik zak jrg

  1. Gabor's signal expansion and the Zak transform.

    PubMed

    Bastiaans, M J

    1994-08-10

    Gabor's expansion of a signal into a discrete set of shifted and modulated versions of an elementary signal is introduced, and its relation to sampling of the sliding-window spectrum is shown. It is shown how Gabor's expansion coefficients can be found as samples of the sliding-window spectrum, in which the window function is related to the elementary signal in such a way that the set of shifted and modulated elementary signals is biorthonormal to the corresponding set of window functions. The Zak transform is introduced, and its intimate relationship to Gabor's signal expansion is demonstrated. It is shown how the Zak transform can be helpful in determining the window function that corresponds to a given elementary signal and how it can be used to find Gabor's expansion coefficients. The continuous-time and the discrete-time cases are considered, and, by sampling the continuous frequency variable that still occurs in the discrete-time case, the discrete Zak transform and the discrete Gabor transform are introduced. It is shown how the discrete transforms enable us to determine Gabor's expansion coefficients by a fast computer algorithm, which is analogous to the well-known fast Fourier-transform= algorithm. PMID:20935912

  2. A Novel Zak Knockout Mouse with a Defective Ribotoxic Stress Response.

    PubMed

    Jandhyala, Dakshina M; Wong, John; Mantis, Nicholas J; Magun, Bruce E; Leong, John M; Thorpe, Cheleste M

    2016-01-01

    Ricin activates the proinflammatory ribotoxic stress response through the mitogen activated protein 3 kinase (MAP3K) ZAK, resulting in activation of mitogen activated protein kinases (MAPKs) p38 and JNK1/2. We had a novel zak-/- mouse generated to study the role of ZAK signaling in vivo during ricin intoxication. To characterize this murine strain, we intoxicated zak-/- and zak+/+ bone marrow-derived murine macrophages with ricin, measured p38 and JNK1/2 activation by Western blot, and measured zak, c-jun, and cxcl-1 expression by qRT-PCR. To determine whether zak-/- mice differed from wild-type mice in their in vivo response to ricin, we performed oral ricin intoxication experiments with zak+/+ and zak-/- mice, using blinded histopathology scoring of duodenal tissue sections to determine differences in tissue damage. Unlike macrophages derived from zak+/+ mice, those derived from the novel zak-/- strain fail to activate p38 and JNK1/2 and have decreased c-jun and cxcl-1 expression following ricin intoxication. Furthermore, compared with zak+/+ mice, zak-/- mice have decreased duodenal damage following in vivo ricin challenge. zak-/- mice demonstrate a distinct ribotoxic stress-associated phenotype in response to ricin and therefore provide a new animal model for in vivo studies of ZAK signaling. PMID:27598200

  3. Zak transform for semidirect product of locally compact groups

    NASA Astrophysics Data System (ADS)

    Arefijamaal, Ali Akbar; Ghaani Farashahi, Arash

    2013-09-01

    Let be a locally compact group and be an LCA group also let be a continuous homomorphism and be the semidirect product of and with respect to . In this article we define the Zak transform on with respect to a -invariant uniform lattice of and we also show that the Zak transform satisfies the Plancherel formula. As an application we analyze how these technique apply for the semidirect product group and also the Weyl-Heisenberg groups.

  4. Structure of the Human Protein Kinase ZAK in Complex with Vemurafenib.

    PubMed

    Mathea, Sebastian; Abdul Azeez, Kamal R; Salah, Eidarus; Tallant, Cynthia; Wolfreys, Finn; Konietzny, Rebecca; Fischer, Roman; Lou, Hua Jane; Brennan, Paul E; Schnapp, Gisela; Pautsch, Alexander; Kessler, Benedikt M; Turk, Benjamin E; Knapp, Stefan

    2016-06-17

    The mixed lineage kinase ZAK is a key regulator of the MAPK pathway mediating cell survival and inflammatory response. ZAK is targeted by several clinically approved kinase inhibitors, and inhibition of ZAK has been reported to protect from doxorubicin-induced cardiomyopathy. On the other hand, unintended targeting of ZAK has been linked to severe adverse effects such as the development of cutaneous squamous cell carcinoma. Therefore, both specific inhibitors of ZAK, as well as anticancer drugs lacking off-target activity against ZAK, may provide therapeutic benefit. Here, we report the first crystal structure of ZAK in complex with the B-RAF inhibitor vemurafenib. The cocrystal structure displayed a number of ZAK-specific features including a highly distorted P loop conformation enabling rational inhibitor design. Positional scanning peptide library analysis revealed a unique substrate specificity of the ZAK kinase including unprecedented preferences for histidine residues at positions -1 and +2 relative to the phosphoacceptor site. In addition, we screened a library of clinical kinase inhibitors identifying several inhibitors that potently inhibit ZAK, demonstrating that this kinase is commonly mistargeted by currently used anticancer drugs. PMID:26999302

  5. Molecular mapping of a stripe rust resistance gene in spring wheat cultivar Zak.

    PubMed

    Sui, X X; Wang, M N; Chen, X M

    2009-10-01

    Stripe rust (yellow rust), caused by Puccinia striiformis f. sp. tritici, is one of the most devastating foliar diseases of wheat (Triticum aestivum) worldwide. Growing resistant cultivars is the best approach for control of the disease. Although the stripe rust resistance in spring wheat cv. Zak has been circumvented by a group of races of the pathogen predominant in the United States since 2000, the resistance genes in Zak were unknown. To identify and map the genes for resistance to stripe rust, Zak was crossed with susceptible wheat genotype 'Avocet Susceptible'. Seedlings of the parents and F1, F2, and F3 progeny were tested with P. striiformis f. sp. tritici races PST-43 and PST-45 under controlled greenhouse conditions. Genetic analysis determined that Zak has a single dominant gene, designated as YrZak, conferring race-specific all-stage resistance. Resistance gene analog polymorphism (RGAP), simple sequence repeat (SSR), and sequence-tagged site (STS) techniques were used to identify molecular markers linked to YrZak. A linkage group of three RGAP, three SSR, and three STS markers was constructed for YrZak using 205 F3 lines. Amplification of the complete set of Chinese Spring nulli-tetrasomic lines with RGAP marker Xwgp102 indicated that YrZak is present on chromosome 2B. The three SSR markers further mapped YrZak to the long arm of chromosome 2B. Amplification of chromosome 2B deletion lines with SSR marker Xgwm501 further confirmed that YrZak is on chromosome 2BL. To determine the genetic distance between YrZak and Yr5, which also is present on chromosome 2BL, 300 F2 plants from cross Zak/Yr5 were tested with PST-43. Six susceptible plants were identified from the F2 population, indicating that YrZak and Yr5 are approximately 42 centimorgans apart. The results of race reactions and chromosomal locations indicated that YrZak is different from previously identified genes for resistance to stripe rust. This gene should be useful in monitoring virulence

  6. The MAP3K ZAK, a novel modulator of ERK-dependent migration, is upregulated in colorectal cancer.

    PubMed

    Rey, C; Faustin, B; Mahouche, I; Ruggieri, R; Brulard, C; Ichas, F; Soubeyran, I; Lartigue, L; De Giorgi, F

    2016-06-16

    Often described as a mediator of cell cycle arrest or as a pro-apoptotic factor in stressful conditions, the MAP3K ZAK (Sterile alpha motif and leucine zipper-containing kinase) has also been proven to positively regulate epidermal growth factor receptor (EGFR) and WNT signaling pathways, cancer cell proliferation and cellular neoplastic transformation. Here, we show that both isoforms of ZAK, ZAK-α and ZAK-β are key factors in cancer cell migration. While ZAK depletion reduced cell motility of HeLa and HCT116 cells, its overexpression triggered the activation of all three mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinase (ERK), c-JUN N-terminal kinase (JNK) and p38, as well as an increase in cell motion. On the contrary, the kinase-dead mutants, ZAK-α K45M and ZAK-β K45M, were not able to provoke such events, and instead exerted a dominant-negative effect on MAPK activation and cell migration. Pharmacological inhibition of ZAK by nilotinib, preventing ZAK-autophosphorylation and thereby auto-activation, led to the same results. Activated by epidermal growth factor (EGF), we further showed that ZAK constitutes an essential element of the EGF/ERK-dependent cell migration pathway. Using public transcriptomic databases and tissue microarrays, we finally established that, as strong factors of the EGFR signaling pathway, ZAK-α and/or ZAK-β transcripts and protein(s) are frequently upregulated in colorectal adenoma and carcinoma patients. Notably, gene set enrichment analysis disclosed a significant correlation between ZAK+ colorectal premalignant lesions and gene sets belonging to the MAPK/ERK and motility-related signaling pathways of the reactome database, strongly suggesting that ZAK induces such pro-tumoral reaction cascades in human cancers. PMID:26522728

  7. Discretization of the Gabor-type scheme by sampling of the Zak transform

    NASA Astrophysics Data System (ADS)

    Zibulski, Meir; Zeevi, Yehoshua Y.

    1994-09-01

    The matrix algebra approach was previously applied in the analysis of the continuous Gabor representation in the Zak transform domain. In this study we analyze the discrete and finite (periodic) scheme by the same approach. A direct relation that exists between the two schemes, based on the sampling of the Zak transform, is established. Specifically, we show that sampling of the Gabor expansion in the Zak transform domain yields a discrete scheme of representation. Such a derivation yields a simple relation between the schemes by means of the periodic extension of the signal. We show that in the discrete Zak domain the frame operator can be expressed by means of a matrix-valued function which is simply the sampled version of the matrix-valued function of the continuous scheme. This result establishes a direct relation between the frame properties of the two schemes.

  8. Sorafenib suppresses JNK-dependent apoptosis through inhibition of ZAK.

    PubMed

    Vin, Harina; Ching, Grace; Ojeda, Sandra S; Adelmann, Charles H; Chitsazzadeh, Vida; Dwyer, David W; Ma, Haiching; Ehrenreiter, Karin; Baccarini, Manuela; Ruggieri, Rosamaria; Curry, Jonathan L; Ciurea, Ana M; Duvic, Madeleine; Busaidy, Naifa L; Tannir, Nizar M; Tsai, Kenneth Y

    2014-01-01

    Sorafenib is U.S. Food and Drug Adminstration-approved for the treatment of renal cell carcinoma and hepatocellular carcinoma and has been combined with numerous other targeted therapies and chemotherapies in the treatment of many cancers. Unfortunately, as with other RAF inhibitors, patients treated with sorafenib have a 5% to 10% rate of developing cutaneous squamous cell carcinoma (cSCC)/keratoacanthomas. Paradoxical activation of extracellular signal-regulated kinase (ERK) in BRAF wild-type cells has been implicated in RAF inhibitor-induced cSCC. Here, we report that sorafenib suppresses UV-induced apoptosis specifically by inhibiting c-jun-NH(2)-kinase (JNK) activation through the off-target inhibition of leucine zipper and sterile alpha motif-containing kinase (ZAK). Our results implicate suppression of JNK signaling, independent of the ERK pathway, as an additional mechanism of adverse effects of sorafenib. This has broad implications for combination therapies using sorafenib with other modalities that induce apoptosis. PMID:24170769

  9. Registration of Zak ERA8 soft white spring wheat germplasm with enhanced response to ABA and increased seed dormancy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ZakERA8 is a unique mutant line selected from mutagenized soft white spring 'Zak' that has increased seed dormancy as a result of enhanced responsiveness to the plant hormone abscisic acid (ABA) during germination. This germplasm was developed by USDA-ARS, Pullman, WA in collaboration with Washingt...

  10. Measurement of the Zak phase of photonic bands through the interface states of a metasurface/photonic crystal

    NASA Astrophysics Data System (ADS)

    Wang, Qiang; Xiao, Meng; Liu, Hui; Zhu, Shining; Chan, C. T.

    2016-01-01

    The Zak phase labels the topological property of one-dimensional Bloch bands. Here we propose a scheme and experimentally measure the Zak phase in a photonic system. The Zak phase of a bulk band is related to the topological properties of the two band gaps sandwiching this band, which in turn can be inferred from the existence or absence of an interface state. Using a reflection spectrum measurement, we determined the existence of interface states in the gaps and then obtained the Zak phases. The knowledge of Zak phases can also help us predict the existence of interface states between a metasurface and a photonic crystal. By manipulating the property of the metasurface, we can further tune the excitation frequency and the polarization of the interface state.

  11. Multiple familial keratoacanthoma of Witten and Zak - A report of three siblings.

    PubMed

    Agarwal, M; Chander, R; Karmakar, S; Walia, R

    1999-01-01

    Three out of 11 siblings of a nonconsanguineous marriage suffering from biopsy-proven multiple small eruptive keratoacanthoma (KA) of Grzybowski as well as large nodular KA of Ferguson-Smith are reported. The response to oral methotrexate was not encouraging. Intravenous 5-fluorouracil (5-FU) at a dose of 12 mg/kg/day in isotonic saline given in weekly 5-day cycles resulted in almost complete resolution of small eruptive lesions and signs of involution in older large agglomerate noduloulcerative KA after 6 cycles. Thus, intravenous 5-FU was found to be an effective therapeutic modality for the Witten and Zak type of KA. PMID:10449942

  12. Exome sequencing and CRISPR/Cas genome editing identify mutations of ZAK as a cause of limb defects in humans and mice

    PubMed Central

    Spielmann, Malte; Kakar, Naseebullah; Tayebi, Naeimeh; Leettola, Catherine; Nürnberg, Gudrun; Sowada, Nadine; Lupiáñez, Darío G.; Harabula, Izabela; Flöttmann, Ricarda; Horn, Denise; Chan, Wing Lee; Wittler, Lars; Yilmaz, Rüstem; Altmüller, Janine; Thiele, Holger; van Bokhoven, Hans; Schwartz, Charles E.; Nürnberg, Peter; Bowie, James U.; Ahmad, Jamil; Kubisch, Christian; Mundlos, Stefan; Borck, Guntram

    2016-01-01

    The CRISPR/Cas technology enables targeted genome editing and the rapid generation of transgenic animal models for the study of human genetic disorders. Here we describe an autosomal recessive human disease in two unrelated families characterized by a split-foot defect, nail abnormalities of the hands, and hearing loss, due to mutations disrupting the SAM domain of the protein kinase ZAK. ZAK is a member of the MAPKKK family with no known role in limb development. We show that Zak is expressed in the developing limbs and that a CRISPR/Cas-mediated knockout of the two Zak isoforms is embryonically lethal in mice. In contrast, a deletion of the SAM domain induces a complex hindlimb defect associated with down-regulation of Trp63, a known split-hand/split-foot malformation disease gene. Our results identify ZAK as a key player in mammalian limb patterning and demonstrate the rapid utility of CRISPR/Cas genome editing to assign causality to human mutations in the mouse in <10 wk. PMID:26755636

  13. Pharmacological Inhibition of the Protein Kinase MRK/ZAK Radiosensitizes Medulloblastoma.

    PubMed

    Markowitz, Daniel; Powell, Caitlin; Tran, Nhan L; Berens, Michael E; Ryken, Timothy C; Vanan, Magimairajan; Rosen, Lisa; He, Mingzu; Sun, Shan; Symons, Marc; Al-Abed, Yousef; Ruggieri, Rosamaria

    2016-08-01

    Medulloblastoma is a cerebellar tumor and the most common pediatric brain malignancy. Radiotherapy is part of the standard care for this tumor, but its effectiveness is accompanied by significant neurocognitive sequelae due to the deleterious effects of radiation on the developing brain. We have previously shown that the protein kinase MRK/ZAK protects tumor cells from radiation-induced cell death by regulating cell-cycle arrest after ionizing radiation. Here, we show that siRNA-mediated MRK depletion sensitizes medulloblastoma primary cells to radiation. We have, therefore, designed and tested a specific small molecule inhibitor of MRK, M443, which binds to MRK in an irreversible fashion and inhibits its activity. We found that M443 strongly radiosensitizes UW228 medulloblastoma cells as well as UI226 patient-derived primary cells, whereas it does not affect the response to radiation of normal brain cells. M443 also inhibits radiation-induced activation of both p38 and Chk2, two proteins that act downstream of MRK and are involved in DNA damage-induced cell-cycle arrest. Importantly, in an animal model of medulloblastoma that employs orthotopic implantation of primary patient-derived UI226 cells in nude mice, M443 in combination with radiation achieved a synergistic increase in survival. We hypothesize that combining radiotherapy with M443 will allow us to lower the radiation dose while maintaining therapeutic efficacy, thereby minimizing radiation-induced side effects. Mol Cancer Ther; 15(8); 1799-808. ©2016 AACR. PMID:27207779

  14. Discovery of Buseckite, (Fe,Zn,Mn)S, a New Mineral in Zakłodzie, an Ungrouped Enstatite-Rich Achondrite

    NASA Astrophysics Data System (ADS)

    Ma, C.; Beckett, J. R.; Rossman, G. R.

    2012-03-01

    We report here new mineral buseckite (Fe,Zn,Mn)S with a wurtzite-type hexagonal structure, and consider the origin of this phase and implications through its formation and survival for the evolution of the Zakłodzie meteorite.

  15. The Armadillo Repeat Gene ZAK IXIK Promotes Arabidopsis Early Embryo and Endosperm Development through a Distinctive Gametophytic Maternal Effect[C][W][OA

    PubMed Central

    Ngo, Quy A.; Baroux, Celia; Guthörl, Daniela; Mozerov, Peter; Collinge, Margaret A.; Sundaresan, Venkatesan; Grossniklaus, Ueli

    2012-01-01

    The proper balance of parental genomic contributions to the fertilized embryo and endosperm is essential for their normal growth and development. The characterization of many gametophytic maternal effect (GME) mutants affecting seed development indicates that there are certain classes of genes with a predominant maternal contribution. We present a detailed analysis of the GME mutant zak ixik (zix), which displays delayed and arrested growth at the earliest stages of embryo and endosperm development. ZIX encodes an Armadillo repeat (Arm) protein highly conserved across eukaryotes. Expression studies revealed that ZIX manifests a GME through preferential maternal expression in the early embryo and endosperm. This parent-of-origin–dependent expression is regulated by neither the histone and DNA methylation nor the DNA demethylation pathways known to regulate some other GME mutants. The ZIX protein is localized in the cytoplasm and nucleus of cells in reproductive tissues and actively dividing root zones. The maternal ZIX allele is required for the maternal expression of MINISEED3. Collectively, our results reveal a reproductive function of plant Arm proteins in promoting early seed growth, which is achieved through a distinct GME of ZIX that involves mechanisms for maternal allele-specific expression that are independent of the well-established pathways. PMID:23064319

  16. Shiga toxin 2-induced intestinal pathology in infant rabbits is A-subunit dependent and responsive to the tyrosine kinase and potential ZAK inhibitor imatinib

    PubMed Central

    Stone, Samuel M.; Thorpe, Cheleste M.; Ahluwalia, Amrita; Rogers, Arlin B.; Obata, Fumiko; Vozenilek, Aimee; Kolling, Glynis L.; Kane, Anne V.; Magun, Bruce E.; Jandhyala, Dakshina M.

    2012-01-01

    Shiga toxin producing Escherichia coli (STEC) are a major cause of food-borne illness worldwide. However, a consensus regarding the role Shiga toxins play in the onset of diarrhea and hemorrhagic colitis (HC) is lacking. One of the obstacles to understanding the role of Shiga toxins to STEC-mediated intestinal pathology is a deficit in small animal models that perfectly mimic human disease. Infant rabbits have been previously used to study STEC and/or Shiga toxin-mediated intestinal inflammation and diarrhea. We demonstrate using infant rabbits that Shiga toxin-mediated intestinal damage requires A-subunit activity, and like the human colon, that of the infant rabbit expresses the Shiga toxin receptor Gb3. We also demonstrate that Shiga toxin treatment of the infant rabbit results in apoptosis and activation of p38 within colonic tissues. Finally we demonstrate that the infant rabbit model may be used to test candidate therapeutics against Shiga toxin-mediated intestinal damage. While the p38 inhibitor SB203580 and the ZAK inhibitor DHP-2 were ineffective at preventing Shiga toxin-mediated damage to the colon, pretreatment of infant rabbits with the drug imatinib resulted in a decrease of Shiga toxin-mediated heterophil infiltration of the colon. Therefore, we propose that this model may be useful in elucidating mechanisms by which Shiga toxins could contribute to intestinal damage in the human. PMID:23162799

  17. Simulation-Assisted Evaluation of Grinding Circuit Flowsheet Design Alternatives: Aghdarreh Gold Ore Processing Plant / Ocena Alternatywnych Schematów Technologicznych Procesu Rozdrabniania W Zakładach Przeróbki Rud Złota W Aghdarreh, Z Wykorzystaniem Metod Symulacji

    NASA Astrophysics Data System (ADS)

    Farzanegan, A.; Ghalaei, A. Ebtedaei

    2015-03-01

    modification. Surowy urobek z kopalni rud złota Aghdarreh musi najpierw zostać poddany rozdrobnieniu, aby zapewnić efektywniejsze uwalnianie cząsteczek złota. W chwili obecnej obiegi rozdrabniania obejmują kruszenie jednostopniowe z wykorzystaniem kruszarek szczękowych oraz kruszenie jednostopniowe z użyciem kruszarek półautomatycznych w obiegu zamkniętym z hydrocyklonem. Odzysk złota odbywa się przy zastosowaniu procesu ługowania, z zastosowaniem metody cyjankowej w szeregu mieszalników. W pracy tej przeprowadzono optymalizację procesu rozdrabniania rud w zakładach przeróbczych Aghdarreh prowadzonego w celu zmniejszenia rozmiarów uzyskiwanych cząsteczek złota (Ps0) z 70 μm do ok. 40 μm poprzez zapewnienie ciągłości procesu, z wykorzystaniem metod modelowania i symulacji. Na podstawie dwóch zestawów próbek z ciągu technologicznego rozdrabniania, rozkłady wielkości cząstek zostały statystycznie zrównoważone z wykorzystaniem oprogramowania NorBal. Pierwszy i drugi zbiór danych otrzymanych na podstawie dwóch zestawów próbek wykorzystany został do kalibracji i walidacji modeli, przed przystąpieniem do właściwych badań symulacyjnych z użyciem oprogramowania MODSIM. Symulacje komputerowe przeprowadzono w celu oceny wydajności dwóch proponowanych ciągów technologicznych. Pierwszy ciąg obejmuje istniejące kruszarki półautomatyczne i nowo proponowaną kruszarkę kulową pracującą w obiegu zamkniętym z hydrocyklonem. Drugi rozważany ciąg stanowi istniejąca kruszarka półautomatyczna, następnie proponowana kruszarka kulowa pracująca w obiegu zamkniętym z istniejącym hydrocyklonem. We wszystkich symulacjach bazowano na modelach SAGT, CYCL i MILL do symulacji pracy kruszarek półautomatycznych, pakietu hydrocyklonu oraz pojedynczych kruszarek. Modele SAGT i MILL oparte są na modelu zrównoważonej populacji w procesie rozdrabniania. Model CYCL opiera się na empirycznym modelu klasyfikacji Plitta

  18. To Make a Male: What Does It Take?

    ERIC Educational Resources Information Center

    Elfer, Jane; Lee, Anthony

    2009-01-01

    This article presents a case study of a year of psychotherapeutic work by a female and male therapist with a 14-year-old boy born with ambiguous genitalia. His mother was also present in the sessions at the request of Zak. We describe the early trauma surrounding Zak's birth and the subsequent desertion of a violent father. We present the…

  19. Biography Today: Sports Series. Profiles of People of Interest to Young Readers. Volume 3, 1999.

    ERIC Educational Resources Information Center

    Harris, Laurie Lanzen, Ed.; Abbey, Cherie D., Ed.

    This third volume is part of a series of biographies that profile individuals of interest to young people over the age of 9 years. The entries in this volume include Joe Dumars, basketball; Jim Harbaugh, football; Dominik Hasek, hockey; Michelle Kwan, figure skating; Rebecca Lobo, basketball; Greg Maddux, baseball; Fatuma Roba, marathon running;…

  20. Comparison of growth, acetate production, and acetate inhibition of Escherichia coli strains in batch and fed-batch fermentations.

    PubMed

    Luli, G W; Strohl, W R

    1990-04-01

    The growth characteristics and acetate production of several Escherichia coli strains were compared by using shake flasks, batch fermentations, and glucose-feedback-controlled fed-batch fermentations to assess the potential of each strain to grow at high cell densities. Of the E. coli strains tested, including JM105, B, W3110, W3100, HB101, DH1, CSH50, MC1060, JRG1046, and JRG1061, strains JM105 and B were found to have the greatest relative biomass accumulation, strain MC1060 accumulated the highest concentrations of acetic acid, and strain B had the highest growth rates under the conditions tested. In glucose-feedback-controlled fed-batch fermentations, strains B and JM105 produced only 2 g of acetate.liter-1 while accumulating up to 30 g of biomass.liter-1. Under identical conditions, strains HB101 and MC1060 accumulated less than 10 g of biomass.liter-1 and strain MC1060 produced 8 g of acetate.liter-1. The addition of various concentrations of sodium acetate to the growth medium resulted in a logarithmic decrease, with respect to acetate concentration, in the growth rates of E. coli JM105, JM105(pOS4201), and JRG1061. These data indicated that the growth of the E. coli strains was likely to be inhibited by the acetate they produced when grown on media containing glucose. A model for the inhibition of growth of E. coli by acetate was derived from these experiments to explain the inhibition of acetate on E. coli strains at neutral pH. PMID:2187400

  1. Comparison of growth, acetate production, and acetate inhibition of Escherichia coli strains in batch and fed-batch fermentations.

    PubMed Central

    Luli, G W; Strohl, W R

    1990-01-01

    The growth characteristics and acetate production of several Escherichia coli strains were compared by using shake flasks, batch fermentations, and glucose-feedback-controlled fed-batch fermentations to assess the potential of each strain to grow at high cell densities. Of the E. coli strains tested, including JM105, B, W3110, W3100, HB101, DH1, CSH50, MC1060, JRG1046, and JRG1061, strains JM105 and B were found to have the greatest relative biomass accumulation, strain MC1060 accumulated the highest concentrations of acetic acid, and strain B had the highest growth rates under the conditions tested. In glucose-feedback-controlled fed-batch fermentations, strains B and JM105 produced only 2 g of acetate.liter-1 while accumulating up to 30 g of biomass.liter-1. Under identical conditions, strains HB101 and MC1060 accumulated less than 10 g of biomass.liter-1 and strain MC1060 produced 8 g of acetate.liter-1. The addition of various concentrations of sodium acetate to the growth medium resulted in a logarithmic decrease, with respect to acetate concentration, in the growth rates of E. coli JM105, JM105(pOS4201), and JRG1061. These data indicated that the growth of the E. coli strains was likely to be inhibited by the acetate they produced when grown on media containing glucose. A model for the inhibition of growth of E. coli by acetate was derived from these experiments to explain the inhibition of acetate on E. coli strains at neutral pH. PMID:2187400

  2. Simulation of Turbulence Using the Stabilization Principle

    NASA Astrophysics Data System (ADS)

    Meyers, Ronald E.; Deacon, Keith S.

    2000-11-01

    The Stabilization Principle developed by Zak and Meyers for solving Navier-Stokes turbulence [ 1,2 ] has been used to simulate turbulent flow over a flat plate and a cylinder. The Stabilization Principle acts on the instantaneous Reynolds stress like a closure by allowing turbulent fluctuations to grow to the level of neutral instability. Experimental stability measurements suppport this approach. Theory and visualization of results will be presented. Computed results appear to provide very realistic space and time simulations of turbulence. [1] M.Zak, J.P. Zbilut, R.E. Meyers, "From Instability to Intelligence: Complexity and Predictability in Nonlinear Dynamics", Springer-Verlag, Lecture Notes in Physics, June 1997. [2] R.E. Meyers, M.Zak, "Representation of Turbulence and Chaos Using the Stabilization Principle", ZAMM, 76, 1996.

  3. Response to Woods--When Rewards and Sanctions Fail: A Case Study of a Primary School Rule-Breaker

    ERIC Educational Resources Information Center

    Rollock, Nicola

    2008-01-01

    Explored through a focus on the behaviour and related experiences of a 9 year old Muslim Somalian boy called Zak, Woods offered a fascinating in-depth case study account of the rewards and sanctions systems in place at a culturally and religiously diverse London primary school. Over a period of 18 months, Woods employed a range of methodological…

  4. Discovery and follow-up of 51 Eri b, a directly-imaged Jupiter-like exoplanet and status of the GPIES campaign.

    NASA Astrophysics Data System (ADS)

    Marchis, Franck; Nielsen, Eric L.; Blunt, Sarah; Rameau, Julien; Barman, Travis; De Rosa, Robert J.; Konopacky, Quinn; Marley, Mark S.; Marois, Christian; Pueyo, Laurent; Rajan, Abhijith; Wang, Jason J.; Macintosh, Bruce; Graham, James R.

    2015-11-01

    Directly detecting thermal emission from young extrasolar planets allows measurement of their atmospheric composition, gravity and luminosity, which is influenced by their formation mechanism. The Gemini Planet Imager Exoplanet Survey (GPIES) is targeting 600 young, nearby stars using the GPI instrument. The star 51 Eridani (51 Eri) was chosen as an early target for the survey due to its youth and proximity. We discovered a planet orbiting the ~20 Myr-old beta Pic moving group member star 51 Eridani at a projected separation of 13 astronomical units (Macintosh et al. Science, 2015). Near-infrared observations show a spectrum with strong methane and water vapor absorption. Modeling of the spectra and photometry yields a luminosity of L/L⦿=1.6-4.0 × 10-6 and an effective temperature of 600-750 K. For this age and luminosity, “hot-start” formation models indicate a mass twice that of Jupiter. This planet also has a sufficiently low luminosity to be the first directly imaged exoplanet to be consistent with the 'cold-start' core accretion process that may have formed Jupiter.Follow-up observations scheduled in Fall 2015 will allow us to constrain the orbit of this exoplanet and derive more information on its atmosphere. These new data, and additional interesting targets, will be presented and discussed.Supported by grants from the National Science Foundation AST-1411868 (BM, KF, JP, AR), AST-0909188 and 1313718 (JRG, PK, RDR, JW), AST-1313718 (MPF and GD) and AST-1405505. Supported by grants from NASA NNX14AJ80G (BM, FM, EN, MP), NNH15AZ591 (DS, MM), NNX15AD95G (JRG, PK), NNX11AD21G (JRG, PK) and NNH11ZDA001N (SM, RP). JR, RD and DL acknowledge support from the Fonds de recherche du Quebec. Portions of this work were performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  5. Cosmic Radiation Fields: Sources in the early Universe

    NASA Astrophysics Data System (ADS)

    Raue, Martin; Kneiske, Tanja; Horns, Dieter; Elsaesser, Dominik; Hauschildt, Peter

    The workshop "Cosmic Radiation Fields - Sources in the Early Universe" (CRF 2010) focuses on the connection between the extragalactic infrared background and sources in the early universe, in particular stars powered by dark matter burning (Dark Stars; DS). The workshop covers the following topics: the cosmic infrared background, formation of early stars, dark stars, effect of dark matter in the early universe, dark matter halos, primordial star formation rate, and reionization. Further information can be found on the conference webpage: http://www.desy.de/crf2010/. Organizing committee: Tanja Kneiske, Martin Raue, Dominik Elsaesser, Alexander Gewering-Peine, Peter Hausschildt, Dieter Horns, and Andreas Maurer.

  6. Topological edge modes in multilayer graphene systems.

    PubMed

    Ge, Lixin; Wang, Li; Xiao, Meng; Wen, Weijia; Chan, C T; Han, Dezhuan

    2015-08-24

    Plasmons can be supported on graphene sheets as the Dirac electrons oscillate collectively. A tight-binding model for graphene plasmons is a good description as the field confinement in the normal direction is strong. With this model, the topological properties of plasmonic bands in multilayer graphene systems are investigated. The Zak phases of periodic graphene sheet arrays are obtained for different configurations. Analogous to Su-Schrieffer-Heeger (SSH) model in electronic systems, topological edge plasmon modes emerge when two periodic graphene sheet arrays with different Zak phases are connected. Interestingly, the dispersion of these topological edge modes is the same as that in the monolayer graphene and is invariant as the geometric parameters of the structure such as the separation and period change. These plasmonic edge states in multilayer graphene systems can be further tuned by electrical gating or chemical doping. PMID:26368137

  7. Direct Measurement of Topological Phases in Discrete-Time Quantum Walks: Theory

    NASA Astrophysics Data System (ADS)

    Ramasesh, Vinay; Flurin, Emmanuel; Siddiqi, Irfan; Yao, Norman

    Quantum walks have been intently investigated theoretically, from initial studies motivated by their connection to classical randomized algorithms to more recent works demonstrating topological phenomena in these walks. In particular, quantum walks simulate dynamics under effective lattice Hamiltonians which feature spin-orbit coupling. Here, we demonstrate that by adding an additional coin operator which varies from step to step, one can perform a traversal of the effective Brillouin zone, analogous to a Bloch oscillation. The geometric phase picked up by the walker along the Bloch oscillation is a genuine signature of the walk's topology, a quantity known in 1D as the Zak phase. Unlike previous interferometric proposals, our work requires neither spin-dependent Ramsey spectroscopy nor an external impurity with additional degrees of freedom. We develop a protocol, illustrating its use in a circuit QED system, which allows for the detection of the Zak phase. This research is supported by the ARO.

  8. Lagrangian Modeling of the Atmosphere

    NASA Astrophysics Data System (ADS)

    Schultz, Colin

    2013-08-01

    Like watching a balloon borne by the breeze, a Lagrangian model tracks a parcel of air as it flows through the atmosphere. Whether running forward or backward in time, Lagrangian models offer a powerful tool for tracking and understanding the fates, or origins, of atmospheric flows. In the AGU monograph Lagrangian Modeling of the Atmosphere, editors John Lin, Dominik Brunner, Christoph Gerbig, Andreas Stohl, Ashok Luhar, and Peter Webley explore the nuances of the modeling technique. In this interview Eos talks to Lin about the growing importance of Lagrangian modeling as the world settles on climate change mitigation strategies, the societal value of operational modeling, and how recent advances are making it possible to run these complex calculations at home.

  9. The classic: On loose bodies in the joint. 1887.

    PubMed

    König, Franz

    2013-04-01

    This Classic Article is a translation of the original work by Franz König, "Ueber freie Körper in den Gelenken" [On loose bodies in the joint]. Dtsch Z Chir. 1887;27: 90-109. available at DOI 10.1007/s11999-013-2824-y (Translated by Drs. Richard A. Brand and Christian-Dominik Peterlein). An accompanying biographical sketch of F. König is available at DOI 10.1007/s11999-013-2823-z . A PDF of the original German is available as supplemental material. (ED Note: An attempt has been made to preserve some of the original wording while placing the material in a contemporary context. In some cases the author's original intent was obscure.). PMID:23404416

  10. Walking over the Composites ---In the Spirit of Sakata---

    NASA Astrophysics Data System (ADS)

    Yamawaki, K.

    I review some topics of the composite models, allrelated with the large anomalous dimension which is characteristic to the ultraviolet (UV) or infrared (IR) stable fixed point in the walking/conformal theories: Walking/Conformal Technicolor based on the Banks-Zaks IR fixed point in the large N_f QCD, Vector Manifestation realized when the Hidden Local Symmetry is matched with the large N_f QCD, and Top Quark Condensate with Extra Dimensions based on a UV fixed point in the higher dimensional standard model.

  11. Bacillus subtilis YxkJ is a secondary transporter of the 2-hydroxycarboxylate transporter family that transports L-malate and citrate.

    PubMed

    Krom, B P; Aardema, R; Lolkema, J S

    2001-10-01

    The genome of Bacillus subtilis contains two genes that code for membrane proteins that belong to the 2-hydroxycarboxylate transporter family. Here we report the functional characterization of one of the two, yxkJ, which codes for a transporter protein named CimHbs. The gene was cloned and expressed in Escherichia coli and complemented the citrate-negative phenotype of wild-type E. coli and the malate-negative phenotype of the E. coli strain JRG4008, which is defective in malate uptake. Subsequent uptake studies in whole cells expressing CimHbs clearly demonstrated the citrate and malate transport activity of the protein. Immunoblot analysis showed that CimHbs is a 48-kDa protein that is well expressed in E. coli. Studies with right-side-out membrane vesicles demonstrated that CimHbs is an electroneutral proton-solute symporter. No indications were found for the involvement of Na(+) ions in the transport process. Inhibition of the uptake catalyzed by CimHbs by divalent metal ions, together with the lack of effect on transport by the chelator EDTA, showed that CimHbs translocates the free citrate and malate anions. Among a large set of substrates tested, only malate, citramalate, and citrate competitively inhibited citrate transport catalyzed by CimHbs. The transporter is strictly stereoselective, recognizing only the S enantiomers of malate and citramalate. Remarkably, though citramalate binds to the transporter, it is not translocated. PMID:11566984

  12. Offshore Wind Farms in the North Sea: Is there an effect on the zooplankton community?

    NASA Astrophysics Data System (ADS)

    Auch, Dominik; Dudeck, Tim; Callies, Ulrich; Riethmüller, Rolf; Hufnagl, Marc; Eckhardt, André; Ove Möller, Klas; Haas, Bianca; Spreitzenbarth, Stefan; van Beusekom, Justus; Walter, Bettina; Temming, Axel; Möllmann, Christian; Floeter, Jens

    2016-04-01

    The climate conference in Paris 2015 has resulted in ambitious goals to mitigate the extent of global climate warming within this century. In Germany, the expansion of renewable energy sources is without any alternative to match the own aims of greenhouse gas reductions. Therefore, in the German EEZ of the North Sea around 10 offshore wind farms (OWFs) are already working and more are currently planned or already under construction. At this already substantial level of offshore wind energy production little is known about the effects of OWFs on the pelagic ecosystem. Earlier investigations have shown an increase of benthic organisms settling on hard substrates provided by the power plant foundations. However, the effects of offshore power plants on lower trophic level organisms within the water column are poorly understood. Thus, we investigated the abundance and distribution of zooplankton within and around OWFs. The analysis was based on optical data derived from a Video Plankton Recorder (VPR). The VPR was mounted on a TRIAXUS system including a suite of different sensors, hence allowing to combine zooplankton information with ambient hydrographic parameters. The combination of the VPR and the TRIAXUS system enabled us to analyse continuous zooplankton and hydrographic data with a high spatial resolution. In this study, we present results of transects through the OWFs Global Tech I, BARD Offshore 1, and Alpha Ventus. The analysis exhibits distinct pattern in the spatial distribution both of physical state variables and of plankton organisms within the vicinity of OWFs, especially of meroplankton, the larval phase of benthic organisms. Keywords: Offshore Wind Farms, Zooplankton, TRIAXUS, Video Plankton Recorder, Meroplankton Corresponding author: Dominik Auch, Institute for Hydrobiology and Fisheries Science, University of Hamburg, Olbersweg 24, 22767 Hamburg, Germany; auch.dominik@web.de

  13. Measuring Z2 topological invariants in optical lattices using interferometry

    NASA Astrophysics Data System (ADS)

    Grusdt, F.; Abanin, D.; Demler, E.

    2014-04-01

    We propose an interferometric method to measure Z2 topological invariants of time-reversal invariant topological insulators realized with optical lattices in two and three dimensions. We suggest two schemes which both rely on a combination of Bloch oscillations with Ramsey interferometry and can be implemented using standard tools of atomic physics. In contrast to topological Zak phase and Chern number, defined for individual one-dimensional and two-dimensional Bloch bands, the formulation of the Z2 invariant involves at least two Bloch bands related by time-reversal symmetry which one must keep track of in measurements. In one of our schemes this can be achieved by the measurement of Wilson loops, which are non-Abelian generalizations of Zak phases. The winding of their eigenvalues is related to the Z2 invariant. We thereby demonstrate that Wilson loops are not just theoretical concepts but can be measured experimentally. For the second scheme we introduce a generalization of time-reversal polarization which is continuous throughout the Brillouin zone. We show that its winding over half the Brillouin zone yields the Z2 invariant. To measure this winding, our protocol only requires Bloch oscillations within a single band, supplemented by coherent transitions to a second band which can be realized by lattice shaking.

  14. Distribution of 7Be, 210Pb and 137Cs in watersheds of different scales in the Seine River basin: inventories and residence times.

    PubMed

    Le Cloarec, Marie-Françoise; Bonté, Philippe; Lefèvre, Irène; Mouchel, Jean-Marie; Colbert, Steven

    2007-04-01

    The activity of environmental radionuclides ((7)Be, (210)Pb and (137)Cs) was monitored in nested catchments, inside the Seine River basin. Suspended matter data was collected at 8 different watersheds, ranging from order 1 to order 7, and ranging in size over 4 orders of magnitude. Suspended matter was analyzed for (210)Pb, (137)Cs and (7)Be, and used to calculate the flux of sediments out of each watershed. Monthly atmospheric flux data of (210)Pb and (7)Be was analyzed to assess the input flux of each into the watersheds, taking into account the rainfall during sampling periods. Taking advantage of the different half-lives of (7)Be (53 days) and (210)Pb (22 years), a two-box model was built for each of the catchments following a methodology previously developed by Dominik et al. [Dominik J, Burrus D, Vernet JP. Transport of the environmental radionuclides in alpine watershed. Earth Planet Sci Letters 1987; 84: 165-180.]. The model divides the watershed into a soil box and a rapid reservoir and provides insight into the removal rate of suspended matter from the surrounding watershed. The model enables the assessment of the surface area and the residence time of slow and rapid reservoirs to describe the fate of contaminants of atmospheric origin inside the river basin. The model was improved by considering the dissolved fraction in the total flux and adding the (137)Cs inventory as an additional constraint. The effects of these changes are discussed. Residence times in the soil box, characterized by low transport velocity, range between 4800 years at Melarchez (order 1) to about 30000 years at Andresy and Poses (order 7). They remain constant in each watershed over a large range of variation of atmospheric fluxes of (7)Be and (210)Pb during the whole study, but are sensitive to SM variations. The residence time in the rapid box, which includes the surface of the river and immediate surroundings, is less than one year, while its surface area is in the range 0.6% to

  15. A chemoproteomic platform to quantitatively map targets of lipid-derived electrophiles

    PubMed Central

    Wang, Chu; Weerapana, Eranthie; Blewett, Megan; Cravatt, Benjamin F.

    2013-01-01

    Cells produce electrophilic products with the potential to modify and affect the function of proteins. Chemoproteomic methods have provided a means to qualitatively inventory proteins targeted by endogenous electrophiles; however, ascertaining the potency and specificity of these reactions to identify the most sensitive sites in the proteome to electrophilic modification requires more quantitative methods. Here, we describe a competitive activity-based profiling method for quantifying the reactivity of electrophilic compounds against 1000+ cysteines in parallel in the human proteome. Using this approach, we identify a select set of proteins that constitute “hot spots” for modification by various lipid-derived electrophiles, including the oxidative stress product 4-hydroxynonenal (HNE). We show that one of these proteins, ZAK kinase, is labeled by HNE on a conserved, active site-proximal cysteine, resulting in enzyme inhibition to create a negative feedback mechanism that can suppress the activation of JNK pathways by oxidative stress. PMID:24292485

  16. Education with Infrared Astronomy and Spitzer

    NASA Astrophysics Data System (ADS)

    Hemphill, Rosa; Blackwell, J. A.; Herrold, A.; Petroff, E.

    2007-12-01

    We present education and outreach results using our experiences involving the Spitzer Space Telescope project, Star Formation in High Redshift Clusters with Spitzer. The project is a collaboration between the Spitzer Science Center and the National Optical Astronomy Observatory. Using the Spitzer Space Telescope, we measured star formation rates in three galaxy clusters at intermediate redshifts. Six teachers were chosen for the program, each with an interest and involvement in astronomy education. From this project, lesson plans, public outreach, lectures and demonstrations were generated which better the understanding of infrared astronomy, multiwavelength astronomy, galaxy and star formation, and cosmology. The teacher mentors are Dr. Gregory Rudnick (NOAO), Dr. Rose Finn (Siena College), and Dr. Vandana Desai (Caltech). Please see the companion posters by Emily Petroff, Zak Schroeder, and Thomas Loughran, et al, for information concerning the science results.

  17. Gabor representation with oversampling

    NASA Astrophysics Data System (ADS)

    Zibulski, Meir; Zeevi, Yehoshua Y.

    1992-11-01

    An approach for characterizing the properties of the basis functions of the Gabor representation in the context of oversampling is presented. The approach is based on the concept of frames and utilizes the Piecewise Zak Transform (PZT). The frame operator associated with the Gabor-type frame, the so-called Weyl-Heisenberg frame, is examined for a rational oversampling rate by representing the frame operator as a matrix-valued function in the PZT domain. Completeness and frame properties of the Gabor representation functions are examined in relation to the properties of the matrix-valued function. The frame bounds are calculated by means of the eigenvalues of the matrix-valued function, and the dual-frame, which is used in calculation of the expansion coefficients, is expressed by means of the inverse matrix.

  18. Matrix approach to frame analysis of Gabor-type image representation

    NASA Astrophysics Data System (ADS)

    Zibulski, Meir; Zeevi, Yehoshua Y.

    1993-11-01

    An approach for characterizing the properties of basis functions which constitute a finite scheme of discrete Gabor representation is presented in the context of oversampling. The approach is based on the concept of frames and utilizes the Piecewise Finite Zak Transform (PFZT). The frame operator associated with the Gabor-type frame is examined by representing the frame operator as a matrix-valued function in the PFZT domain. The frame property of the Gabor representation functions are examined in relation to the properties of the matrix-valued function. The frame bounds are calculated by means of the eigenvalues of the matrix-valued function, and the dual frame, which is used in calculation of the expansion coefficients, is expressed by means of the inverse matrix. DFT-based algorithms for computation of the expansion coefficients, and for the reconstruction of signals from these coefficients are generalized for the case of oversampling of the Gabor space.

  19. Topological interface states in multiscale spoof-insulator-spoof waveguides.

    PubMed

    Meng, Yan; Xiang, Hong; Zhang, Ruo-Yang; Wu, Xiaoxiao; Han, Dezhuan; Chan, C T; Wen, Weijia

    2016-08-15

    The spoof-insulator-spoof (SIS) structure can serve as a waveguide for spoof surface plasmon polaritons (spoof SPPs). If a periodic geometry modulation in the wavelength scale is introduced to the SIS waveguide, this multiscale SIS (MSIS) waveguide possesses band gaps for spoof SPPs analogous to the band gaps in a photonic crystal. Inspired by the topological interface states found in photonic crystals, we construct an interface by connecting two MSIS waveguides with different topological properties (inverted Zak phases of bulk bands). The topological interface states in the MSIS waveguides are observed experimentally. The measured decay lengths of the interface states agree excellently with the numerical results. These localized interface states may find potential applications in miniaturized microwave devices. PMID:27519066

  20. Fuzzy model-based observers for fault detection in CSTR.

    PubMed

    Ballesteros-Moncada, Hazael; Herrera-López, Enrique J; Anzurez-Marín, Juan

    2015-11-01

    Under the vast variety of fuzzy model-based observers reported in the literature, what would be the properone to be used for fault detection in a class of chemical reactor? In this study four fuzzy model-based observers for sensor fault detection of a Continuous Stirred Tank Reactor were designed and compared. The designs include (i) a Luenberger fuzzy observer, (ii) a Luenberger fuzzy observer with sliding modes, (iii) a Walcott-Zak fuzzy observer, and (iv) an Utkin fuzzy observer. A negative, an oscillating fault signal, and a bounded random noise signal with a maximum value of ±0.4 were used to evaluate and compare the performance of the fuzzy observers. The Utkin fuzzy observer showed the best performance under the tested conditions. PMID:26521723

  1. Topological Optical Waveguiding in Silicon and the Transition between Topological and Trivial Defect States.

    PubMed

    Blanco-Redondo, Andrea; Andonegui, Imanol; Collins, Matthew J; Harari, Gal; Lumer, Yaakov; Rechtsman, Mikael C; Eggleton, Benjamin J; Segev, Mordechai

    2016-04-22

    One-dimensional models with topological band structures represent a simple and versatile platform to demonstrate novel topological concepts. Here we experimentally study topologically protected states in silicon at the interface between two dimer chains with different Zak phases. Furthermore, we propose and demonstrate that, in a system where topological and trivial defect modes coexist, we can probe them independently. Tuning the configuration of the interface, we observe the transition between a single topological defect and a compound trivial defect state. These results provide a new paradigm for topologically protected waveguiding in a complementary metal-oxide-semiconductor compatible platform and highlight the novel concept of isolating topological and trivial defect modes in the same system that can have important implications in topological physics. PMID:27152805

  2. Molecular mapping of a gene for stripe rust resistance in spring wheat cultivar IDO377s.

    PubMed

    Cheng, P; Chen, X M

    2010-06-01

    Stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the most important diseases of wheat worldwide. The best strategy to control stripe rust is to grow resistant cultivars. One such cultivar resistant to most races in North America is 'IDO377s'. To study the genetics of its resistance this spring wheat cultivar was crossed with 'Avocet Susceptible' (AvS). Seedlings of the parents, F(2) plants, and F(3) lines were tested under controlled greenhouse conditions with races PST-43 and PST-45 of P. striiformis f. sp. tritici. IDO377s carries a single dominant gene for resistance. Resistance gene analog polymorphism (RGAP) and simple sequence repeat (SSR) techniques were used to identify molecular markers linked to the resistance gene. A total of ten markers were identified, two of which flanked the locus at 4.4 and 5.5 cM. These flanking RGAP markers were located on chromosome 2B with nulli-tetrasomic lines of 'Chinese Spring'. Their presence in the ditelosomic 2BL line localized them to the long arm. The chromosomal location of the resistance gene was further confirmed with two 2BL-specific SSR markers and a sequence tagged site (STS) marker previously mapped to 2BL. Based on the chromosomal location, reactions to various races of the pathogen and tests of allelism, the IDO377s gene is different from all previously designated genes for stripe rust resistance, and is therefore designated Yr43. A total of 108 wheat breeding lines and cultivars with IDO377s or related cultivars in their parentage were assayed to assess the status of the closest flanking markers and to select lines carrying Yr43. The results showed that the flanking markers were reliable for assisting selection of breeding lines carrying the resistance gene. A linked stripe rust resistance gene, previously identified as YrZak, in cultivar Zak was designated Yr44. PMID:20198466

  3. Planet Formation

    NASA Astrophysics Data System (ADS)

    Klahr, Hubert; Brandner, Wolfgang

    2011-02-01

    1. Historical notes on planet formation Bodenheimer; 2. The formation and evolution of planetary systems Bouwman et al.; 3. Destruction of protoplanetary disks by photoevaporation Richling, Hollenbach and Yorke; 4. Turbulence in protoplanetary accretion disks Klahr, Rozyczka, Dziourkevitch, Wunsch and Johansen; 5. The origin of solids in the early solar system Trieloff and Palme; 6. Experiments on planetesimal formation Wurm and Blum; 7. Dust coagulation in protoplanetary disks Henning, Dullemond, Wolf and Dominik; 8. The accretion of giant planet cores Thommes and Duncan; 9. Planetary transits: direct vision of extrasolar planets Lecavelier des Etangs and Vidal-Madjar; 10. The core accretion - gas capture model Hubickyj; 11. Properties of exoplanets Marcy, Fischer, Butler and Vogt; 12. Giant planet formation: theories meet observations Boss; 13. From hot Jupiters to hot Neptures … and below Lovis, Mayor and Udry; 14. Disk-planet interaction and migration Masset and Kley; 15. The Brown Dwarf - planet relation Bate; 16. From astronomy to astrobiology Brandner; 17. Overview and prospective Lin.

  4. THE PHYSICS OF PROTOPLANETESIMAL DUST AGGLOMERATES. VI. EROSION OF LARGE AGGREGATES AS A SOURCE OF MICROMETER-SIZED PARTICLES

    SciTech Connect

    Schraepler, Rainer; Blum, Juergen

    2011-06-20

    Observed protoplanetary disks consist of a large amount of micrometer-sized particles. Dullemond and Dominik pointed out for the first time the difficulty in explaining the strong mid-infrared excess of classical T Tauri stars without any dust-retention mechanisms. Because high relative velocities in between micrometer-sized and macroscopic particles exist in protoplanetary disks, we present experimental results on the erosion of macroscopic agglomerates consisting of micrometer-sized spherical particles via the impact of micrometer-sized particles. We find that after an initial phase, in which an impacting particle erodes up to 10 particles of an agglomerate, the impacting particles compress the agglomerate's surface, which partly passivates the agglomerates against erosion. Due to this effect, the erosion halts for impact velocities up to {approx}30 m s{sup -1} within our error bars. For higher velocities, the erosion is reduced by an order of magnitude. This outcome is explained and confirmed by a numerical model. In a next step, we build an analytical disk model and implement the experimentally found erosive effect. The model shows that erosion is a strong source of micrometer-sized particles in a protoplanetary disk. Finally, we use the stationary solution of this model to explain the amount of micrometer-sized particles in the observational infrared data of Furlan et al.

  5. Laser induced alignment of molecules dissolved in Helium nanodroplets

    NASA Astrophysics Data System (ADS)

    Stapelfeldt, Henrik

    2013-05-01

    Laser induced alignment, the method to confine the principal axes of molecules along axes fixed in the laboratory frame, is now used in a range of applications in physics and chemistry. With a few exceptions all studies have focused on isolated molecules in the gas phase. In this talk we present experimental studies of laser induced alignment of molecules embedded in the solvent of a superfluid helium nanodroplet. Alignment is conducted in both the adiabatic and the nonadiabtic regime where the alignment pulse is much longer or shorter, respectively, than the rotational period of the molecules. In the nonadiabatic limit, induced by a few-hundred femtosecond long laser pulse, we show that methyliodide molecules reach an alignment maximum 20 ps after the alignment pulse and gradually loose the alignment completely in another 60 ps. This dynamics is completely different from that of isolated methyliodide molecules where alignment occurs in regularly spaced (by 33.3 ps), narrow time windows, termed revivals. Adiabatic alignment, induced by 10 ns laser pulses, resembles the gas phase behavior although the observed degree of alignment falls below that of isolated molecules. Work done in collaboration with Dominik Pentkehner, Department of Chemistry, Aarhus University; Jens Hedegaard Nielsen, Department of Physics, Aarhus University; Alkwin Slenczka, Department of Chemistry, Regensburg University; and Klaus Mølmer, Department of Physics, Aarhus University.

  6. The Formation Of The First Solids In The Solar System: An Investigation Of CAI Diversity

    NASA Astrophysics Data System (ADS)

    Taillifet, Esther; Baillié, K.; Charnoz, S.; Aléon, J.

    2012-10-01

    Chondritic meteorites are primitive bodies and therefore an important source of information on the first moments of planets formation. Chondrites contain several materials especially calcium and aluminum rich inclusions (CAIs), known to be the oldest objects of the solar system (4.567 Gyr - Amelin et al., 2002; Connelly et al., 2008) and thus the first solids to be formed. CAIs appear in various textures, sizes and compositions in chondrites. Though, all of them should have formed at high temperature (1300-1800 K) in the same region of the solar nebula by condensation from the gas (e.g. Grossman, 1972; Yoneda & Grossman, 1995; Petaev & Wood, 1998; Ebel & Grossman 2000). To answer this problem we study the CAI formation within the solar nebula using numerical simulations. For this work we developed a self consistent thermodynamical model of the solar nebula (see associated talk from Baillié et. al ) based on previous works (Calvet et. al, 1991; Hueso & Guillot, 2005; Dullemond, Dominik and Natta, 2001). Using this model, we simulate the young system with Lagrangian Implicit Disk Transport code (LIDT - Charnoz et. al, 2010). We will focus on the very first instants of the CAIs within the few years following their condensation. We will report our first results in terms of thermal history and investigate if turbulence-driven transport may explain the CAI diversity.

  7. Herbig stars' near-infrared excess: An origin in the protostellar disk's magnetically supported atmosphere

    SciTech Connect

    Turner, N. J.; Benisty, M.; Dullemond, C. P.; Hirose, S.

    2014-01-01

    Young stars with masses 2-8 times solar, the Herbig Ae and Be stars, often show a near-infrared excess too large to explain with a hydrostatically supported circumstellar disk of gas and dust. At the same time, the accretion flow carrying the circumstellar gas to the star is thought to be driven by magnetorotational turbulence, which, according to numerical MHD modeling, yields an extended low-density atmosphere supported by the magnetic fields. We demonstrate that the base of the atmosphere can be optically thick to the starlight and that the parts lying near 1 AU are tall enough to double the fraction of the stellar luminosity reprocessed into the near-infrared. We generate synthetic spectral energy distributions (SEDs) using Monte Carlo radiative transfer calculations with opacities for submicron silicate and carbonaceous grains. The synthetic SEDs closely follow the median Herbig SED constructed recently by Mulders and Dominik and, in particular, match the large near-infrared flux, provided the grains have a mass fraction close to interstellar near the disk's inner rim.

  8. Compression behavior of porous dust agglomerates

    NASA Astrophysics Data System (ADS)

    Seizinger, A.; Speith, R.; Kley, W.

    2012-05-01

    Context. The early planetesimal growth proceeds through a sequence of sticking collisions of dust agglomerates. Very uncertain is still the relative velocity regime in which growth rather than destruction can take place. The outcome of a collision depends on the bulk properties of the porous dust agglomerates. Aims: Continuum models of dust agglomerates require a set of material parameters that are often difficult to obtain from laboratory experiments. Here, we aim at determining those parameters from ab initio molecular dynamics simulations. Our goal is to improve on the existing model that describe the interaction of individual monomers. Methods: We use a molecular dynamics approach featuring a detailed micro-physical model of the interaction of spherical grains. The model includes normal forces, rolling, twisting and sliding between the dust grains. We present a new treatment of wall-particle interaction that allows us to perform customized simulations that directly correspond to laboratory experiments. Results: We find that the existing interaction model by Dominik & Tielens leads to a too soft compressive strength behavior for uni- and omni-directional compression. Upon making the rolling and sliding coefficients stiffer we find excellent agreement in both cases. Additionally, we find that the compressive strength curve depends on the velocity with which the sample is compressed. Conclusions: The modified interaction strengths between two individual dust grains will lead to a different behavior of the whole dust agglomerate. This will influences the sticking probabilities and hence the growth of planetesimals. The new parameter set might possibly lead to an enhanced sticking as more energy can be stored in the system before breakup.

  9. Characteristics of dune-paleosol-sequences in Fuerteventura. - What should be questioned?

    NASA Astrophysics Data System (ADS)

    Faust, Dominik; Willkommen, Tobias; Yanes, Yurena; Richter, David; Zöller, Ludwig

    2013-04-01

    Characteristics of dune-paleosol-sequences in Fuerteventura. - What should be questioned? Dominik Faust, TU Dresden, Germany Tobias Willkommen, TU Dresden, Germany Yurena Yanes, CSIC Granada/Cincinatti, Spain/USA David Richter, TU Dresden, Germany Ludwig Zöller, Uni Bayreuth, Germany The northern part of Fuerteventura is characterized by large dune fields. We investigated dune-paleosol-sequences in four pits to establish a robust stratigraphy and to propose a standard section. An interaction of processes like dune formation, soil formation and redeposition of soils and sand are most important to understand the principles of landscape development in the study area. To our mind a process cycle seem to be important: First climbing-dunes are formed by sand of shelf origin. Then soil formation could have taken place. Soil and/or sand were then eroded and deposited at toe slope position. This material in turn is the source of new sand supply and dune formation. The described cycle may be repeated several times and this ping-pong-process holds on. The results are sections composed of dune layers, paleosols and colluvial material interbedded. Fundamental questions still remain unanswered: Is climate change responsable for changes in process combination (e.g. from dune formation to soil formation)? Or are these features due to divergence phenomenon, where different effects/results (dune and soils) may be linked to similar causes (here: climate)? Assuming that different features (soils and dunes) were formed under one climate, increasing soil forming intensity could be mainly a function of decreasing sand supply. This in turn could be caused by reduced sand production (s. ZECH et al. accepted). However geochemical data and mollusc assemblages point to changing environments in space and even climate modifications in time.

  10. Topological water wave states in a one-dimensional structure

    PubMed Central

    Yang, Zhaoju; Gao, Fei; Zhang, Baile

    2016-01-01

    Topological concepts have been introduced into electronic, photonic, and phononic systems, but have not been studied in surface-water-wave systems. Here we study a one-dimensional periodic resonant surface-water-wave system and demonstrate its topological transition. By selecting three different water depths, we can construct different types of water waves - shallow, intermediate and deep water waves. The periodic surface-water-wave system consists of an array of cylindrical water tanks connected with narrow water channels. As the width of connecting channel varies, the band diagram undergoes a topological transition which can be further characterized by Zak phase. This topological transition holds true for shallow, intermediate and deep water waves. However, the interface state at the boundary separating two topologically distinct arrays of water tanks can exhibit different bands for shallow, intermediate and deep water waves. Our work studies for the first time topological properties of water wave systems, and paves the way to potential management of water waves. PMID:27373982

  11. [Iodine content of cattle milk from mountain and coast from Perú].

    PubMed

    Cárdenas Quintana, Haydeé; Gómez Bravo, Carlos; Pretell, Eduardo A

    2003-12-01

    With the objective to establish the cause-effect relationship between a geological area and the iodine content in cattle milk, and to estimate the contribution of milk consumption to the dietary iodine intake, the iodine content in cattle milk from the sierra and the coastal regions of Perú was determined. Milk samples were collected of cows from the three main productive zones of Perú, 62 in Cajamarca, 42 in Arequipa, both in the sierra, and 27 in Lima at the coast. The measurement of iodine was made by the method of Zak, based on the Sandell- Kolthoff reaction. The median values obtained were 24 microg/L in Cajamarca, 34 microg/L in Arequipa, and 170 microg/L in Lima. The median value in the sierra, 26 microg/L, was significantly lower than the one found in the coast. Moreover, while in the former 81% of individual values were below 50 microg/L, in the latter, on the contrary, 77% were above 80 microg/L. These results confirm that the iodine content in cattle milk is related to ecological factors. At the same time, they demonstrate that the iodine content in milk from the sierra is six times lower than in milk from the coast, and also that its consumption does not contribute significantly to satisfy the human physiological requirements of iodine in that zone. PMID:15125084

  12. The Treatment of Restless Legs Syndrome and Periodic Limb Movement Disorder in Adults—An Update for 2012: Practice Parameters with an Evidence-Based Systematic Review and Meta-Analyses

    PubMed Central

    Aurora, R. Nisha; Kristo, David A.; Bista, Sabin R.; Rowley, James A.; Zak, Rochelle S.; Casey, Kenneth R.; Lamm, Carin I.; Tracy, Sharon L.; Rosenberg, Richard S.

    2012-01-01

    A systematic literature review and meta-analyses (where appropriate) were performed to update the previous AASM practice parameters on the treatments, both dopaminergic and other, of RLS and PLMD. A considerable amount of literature has been published since these previous reviews were performed, necessitating an update of the corresponding practice parameters. Therapies with a STANDARD level of recommendation include pramipexole and ropinirole. Therapies with a GUIDELINE level of recommendation include levodopa with dopa decarboxylase inhibitor, opioids, gabapentin enacarbil, and cabergoline (which has additional caveats for use). Therapies with an OPTION level of recommendation include carbamazepine, gabapentin, pregabalin, clonidine, and for patients with low ferritin levels, iron supplementation. The committee recommends a STANDARD AGAINST the use of pergolide because of the risks of heart valve damage. Therapies for RLS secondary to ESRD, neuropathy, and superficial venous insufficiency are discussed. Lastly, therapies for PLMD are reviewed. However, it should be mentioned that because PLMD therapy typically mimics RLS therapy, the primary focus of this review is therapy for idiopathic RLS. Citation: Aurora RN; Kristo DA; Bista SR; Rowley JA: Zak RS; Casey KR; Lamm CI; Tracy SL; Rosenberg RS. The treatment of restless legs syndrome and periodic limb movement disorder in adults—an update for 2012: practice parameters with an evidence-based systematic review and meta-analyses. SLEEP 2012;35(8):1039-1062. PMID:22851801

  13. Disentangling running coupling and conformal effects in QCD

    SciTech Connect

    Brodsky, S. J.; Gardi, E.; Grunberg, G.; Rathsman, J.

    2001-05-01

    We investigate the relation between a postulated skeleton expansion and the conformal limit of QCD. We begin by developing some consequences of an Abelian-like skeleton expansion, which allows one to disentangle running-coupling effects from the remaining skeleton coefficients. The latter are by construction renormalon free, and hence hopefully better behaved. We consider a simple ansatz for the expansion, where an observable is written as a sum of integrals over the running coupling. We show that in this framework one can set a unique Brodsky-Lepage-Mackenzie (BLM) scale-setting procedure as an approximation to the running-coupling integrals, where the BLM coefficients coincide with the skeleton ones. Alternatively, the running-coupling integrals can be approximated using the effective charge method. We discuss the limitations in disentangling running coupling effects in the absence of a diagrammatic construction of the skeleton expansion. Independently of the assumed skeleton structure we show that BLM coefficients coincide with conformal coefficients defined in the small {beta}{sub 0} (Banks-Zaks) limit where a perturbative infrared fixed point is present. This interpretation of the BLM coefficients should explain their previously observed simplicity and smallness. Numerical examples are critically discussed.

  14. Consistent Perturbative Fixed Point Calculations in QCD and Supersymmetric QCD

    NASA Astrophysics Data System (ADS)

    Ryttov, Thomas A.

    2016-08-01

    We suggest how to consistently calculate the anomalous dimension γ* of the ψ ¯ ψ operator in finite order perturbation theory at an infrared fixed point for asymptotically free theories. If the n +1 loop beta function and n loop anomalous dimension are known, then γ* can be calculated exactly and fully scheme independently in a Banks-Zaks expansion through O (Δfn) , where Δf=N¯ f-Nf , Nf is the number of flavors, and N¯f is the number of flavors above which asymptotic freedom is lost. For a supersymmetric theory, the calculation preserves supersymmetry order by order in Δf. We then compute γ* through O (Δf2) for supersymmetric QCD in the dimensional reduction scheme and find that it matches the exact known result. We find that γ* is astonishingly well described in perturbation theory already at the few loops level throughout the entire conformal window. We finally compute γ* through O (Δf3) for QCD and a variety of other nonsupersymmetric fermionic gauge theories. Small values of γ* are observed for a large range of flavors.

  15. Topological water wave states in a one-dimensional structure

    NASA Astrophysics Data System (ADS)

    Yang, Zhaoju; Gao, Fei; Zhang, Baile

    2016-07-01

    Topological concepts have been introduced into electronic, photonic, and phononic systems, but have not been studied in surface-water-wave systems. Here we study a one-dimensional periodic resonant surface-water-wave system and demonstrate its topological transition. By selecting three different water depths, we can construct different types of water waves - shallow, intermediate and deep water waves. The periodic surface-water-wave system consists of an array of cylindrical water tanks connected with narrow water channels. As the width of connecting channel varies, the band diagram undergoes a topological transition which can be further characterized by Zak phase. This topological transition holds true for shallow, intermediate and deep water waves. However, the interface state at the boundary separating two topologically distinct arrays of water tanks can exhibit different bands for shallow, intermediate and deep water waves. Our work studies for the first time topological properties of water wave systems, and paves the way to potential management of water waves.

  16. Nature of Pressure-induced Insulating States in Simple Metals

    NASA Astrophysics Data System (ADS)

    Naumov, Ivan; Hemley, Russell

    As experimentally established, all the alkali metals and heavy alkaline earth metals (Ca, Sr and Ba) become progressively less conductive on compression, at least up to some critical limit over a broad pressure range. Of these metals, Li and Na clearly undergo pressure-induced metal-insulator transitions, which may also be called reverse Mott transitions. Here, using group theory arguments and first-principles calculations, we show that such transitions can be understood in terms of band representations introduced by Zak. The valence bands in the insulating states are described by simple and composite band representations constructed from localized Wannier functions centered on points unoccupied by atoms. The character of the Wannier functions is closely related to the degree of s-p(-d) hybridization and reflects multi-center chemical bonding in these insulating states. The conditions under which an insulating state is allowed for structures having an integer number of atoms per primitive unit cell as well as re-entrant (i.e., metal-insulator-metal) transition sequences are detailed, resulting in predictions of semimetallic phases with flat surface states. The general principles developed are tested and applied to the alkali and alkaline earth metals, including elements where high-pressure insulating phases have been identified or reported (e.g., Li, Na, and Ca). This research was supported by EFree, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award DESC0001057.

  17. Long-range doublon transfer in a dimer chain induced by topology and ac fields.

    PubMed

    Bello, M; Creffield, C E; Platero, G

    2016-01-01

    The controlled transfer of particles from one site of a spatial lattice to another is essential for many tasks in quantum information processing and quantum communication. In this work we study how to induce long-range transfer between the two ends of a dimer chain, by coupling states that are localized just on the chain's end-points. This has the appealing feature that the transfer occurs only between the end-points - the particle does not pass through the intermediate sites-making the transfer less susceptible to decoherence. We first show how a repulsively bound-pair of fermions, known as a doublon, can be transferred from one end of the chain to the other via topological edge states. We then show how non-topological surface states of the familiar Shockley or Tamm type can be used to produce a similar form of transfer under the action of a periodic driving potential. Finally we show that combining these effects can produce transfer by means of more exotic topological effects, in which the driving field can be used to switch the topological character of the edge states, as measured by the Zak phase. Our results demonstrate how to induce long range transfer of strongly correlated particles by tuning both topology and driving. PMID:26932406

  18. Long-range doublon transfer in a dimer chain induced by topology and ac fields

    NASA Astrophysics Data System (ADS)

    Bello, M.; Creffield, C. E.; Platero, G.

    2016-03-01

    The controlled transfer of particles from one site of a spatial lattice to another is essential for many tasks in quantum information processing and quantum communication. In this work we study how to induce long-range transfer between the two ends of a dimer chain, by coupling states that are localized just on the chain’s end-points. This has the appealing feature that the transfer occurs only between the end-points - the particle does not pass through the intermediate sites-making the transfer less susceptible to decoherence. We first show how a repulsively bound-pair of fermions, known as a doublon, can be transferred from one end of the chain to the other via topological edge states. We then show how non-topological surface states of the familiar Shockley or Tamm type can be used to produce a similar form of transfer under the action of a periodic driving potential. Finally we show that combining these effects can produce transfer by means of more exotic topological effects, in which the driving field can be used to switch the topological character of the edge states, as measured by the Zak phase. Our results demonstrate how to induce long range transfer of strongly correlated particles by tuning both topology and driving.

  19. Quality Measures for the Care of Adult Patients with Restless Legs Syndrome

    PubMed Central

    Trotti, Lynn Marie; Goldstein, Cathy A.; Harrod, Christopher G.; Koo, Brian B.; Sharon, Denise; Zak, Rochelle; Chervin, Ronald D.

    2015-01-01

    The American Academy of Sleep Medicine (AASM) commissioned several Workgroups to develop quality measures for the care of patients with common sleep disorders, including adults with restless legs syndrome (RLS). Using the AASM process for quality measure development, the RLS Work-group developed three target outcomes for RLS management, including improving the accuracy of diagnosis, reducing symptom severity, and minimizing treatment complications. Seven processes were developed to support these outcomes. To achieve the outcome of improving accuracy of diagnosis, the use of accepted diagnostic criteria and assessment of iron stores are recommended. To realize the outcome of decreasing symptom severity, routine assessment of severity and provision of evidence-based treatment are recommended. To support the outcome of minimizing treatment complications, counseling about potential side effects and assessing for augmentation and impulse control disorders, when indicated, are recommended. Further research is needed to validate optimal practice processes to achieve best outcomes in adult patients with RLS. Citation: Trotti LM, Goldstein CA, Harrod CG, Koo BB, Sharon D, Zak R, Chervin RD. Quality measures for the care of adult patients with restless legs syndrome. J Clin Sleep Med 2015;11(3):293–310. PMID:25700882

  20. [A comparative analysis of occupational risk in industry employees based on concentrations of some elements in teeth and body fluids].

    PubMed

    Poczatek, Michał; Machoy, Zygmunt; Gutowska, Izabela; Chlubek, Dariusz

    2004-01-01

    Work safety and hygiene is a set of basic measures to protect workers from the negative effects of manufacturing processes. So far, numerous procedures for assessment of occupational health risk have been described. We measured the concentrations of some elements in teeth and body fluids of employees working in three different industries with an established production profile: Zakłady Naprawcze Taboru Kolejowego (repairs of rail vehicles), Philips Lighting Poland (production of lighting systems) and Metalplast (build ing furbishing factory). Different technologies were in place at each of these plants. Basing on laboratory analyses, the risk of exposure to chemical substances was evaluated. The study material included 100 extracted teeth, as well as body fluid samples (saliva, urine and blood) collected during routine health checks. Whenever possible, concentrations of the following elements were measured: calcium, magnesium, fluorine, phosphorus in the form of phosphates, potassium, sodium, iron, zinc, copper, cadmium, and lead. Metal elements were measured spectrophotometrically (ASA), fluorine with an ion-selective electrode, and phosphates with a colorimetric method. We found that concentrations of the elements in teeth and body fluids differed depending on the industry. For teeth, statistically significant differences applied to magnesium, phosphates, zinc, sodium, and potassium. In body fluids, statistically significant differences were found for calcium (blood and urine), magnesium (blood, urine and saliva), zinc (blood, urine and saliva), iron, lead and copper (urine). In conclusion, our findings may be helpful for monitoring safety at work in industrial plants. PMID:16871749

  1. Exploring arbitrarily high orders of optimized perturbation theory in QCD with nf → 161/2

    NASA Astrophysics Data System (ADS)

    Stevenson, P. M.

    2016-09-01

    Perturbative QCD with nf flavours of massless quarks becomes simple in the hypothetical limit nf → 161/2, where the leading β-function coefficient vanishes. The Banks-Zaks (BZ) expansion in a0 ≡8/321 (161/2 -nf) is straightforward to obtain from perturbative results in MS ‾ or any renormalization scheme (RS) whose nf dependence is 'regular'. However, 'irregular' RS's are perfectly permissible and should ultimately lead to the same BZ results. We show here that the 'optimal' RS determined by the Principle of Minimal Sensitivity does yield the same BZ-expansion results when all orders of perturbation theory are taken into account. The BZ limit provides an arena for exploring optimized perturbation theory at arbitrarily high orders. These explorations are facilitated by a 'master equation' expressing the optimization conditions in the fixed-point limit. We find an intriguing strong/weak coupling duality a →a*2 / a about the fixed point a*.

  2. Multiwindow Gabor-type transform for signal representation and analysis

    NASA Astrophysics Data System (ADS)

    Zibulski, Meir; Zeevi, Yehoshua Y.

    1995-09-01

    The Gabor scheme is generalized to incorporate several window functions as well as kernels other than the exponential. The properties of the sequence of representation functions are characterized by an approach based on the concept of frames. the frame operator associated with the multi-window Gabor-type frame, is examined for a rational oversampling rate by representing the frame operator as a finite order matrix-valued function in the Zak Transform domain. Completeness and frame properties of the sequence of representation functions are examined in relation to the properties of the matrix-valued function. Calculation of the frame bounds and the dual frame, as well as the issue of tight frames are considered. It is shown that the properties of the sequence of representation functions are essentially not changed by replacing the widely-used exponential kernel with other kernels. The issue of a different sampling rate for each window is also considered. The so-called Balian-Low theorem is generalized to consideration of a scheme of multi-windows, which makes it possible to overcome the constraint imposed by the original theorem in the case of a single window.

  3. Matrix algebra approach to Gabor-type image representation

    NASA Astrophysics Data System (ADS)

    Zibulski, Meir; Zeevi, Yehoshua Y.

    1993-10-01

    Properties of basis functions which constitute a finite scheme of discrete Gabor representation are investigated. The approach is based on the concept of frames and utilizes the Piecewise Finite Zak Transform (PFZT). The frame operator associated with the Gabor-type frame is examined by representing it as a matrix-values function in the PFZT domain. The frame property of the Gabor representation functions are examined in relation to the properties of the matrix-valued function. The frame bounds are calculated by means of the eignevalues of the matrix-valued function, and the dual frame, which is used in calculation of the expansion coefficients, is expressed by means of the inverse matrix. DFT-based algorithms for computation of the expansion coefficients, and for the reconstruction of signals from these coefficients are generalized for the case of oversampling of the Gabor space. It is illustrated by an example that a better reconstruction is obtained in from the same number of coefficients in the case of oversampling.

  4. Long-range doublon transfer in a dimer chain induced by topology and ac fields

    PubMed Central

    Bello, M.; Creffield, C. E.; Platero, G.

    2016-01-01

    The controlled transfer of particles from one site of a spatial lattice to another is essential for many tasks in quantum information processing and quantum communication. In this work we study how to induce long-range transfer between the two ends of a dimer chain, by coupling states that are localized just on the chain’s end-points. This has the appealing feature that the transfer occurs only between the end-points – the particle does not pass through the intermediate sites–making the transfer less susceptible to decoherence. We first show how a repulsively bound-pair of fermions, known as a doublon, can be transferred from one end of the chain to the other via topological edge states. We then show how non-topological surface states of the familiar Shockley or Tamm type can be used to produce a similar form of transfer under the action of a periodic driving potential. Finally we show that combining these effects can produce transfer by means of more exotic topological effects, in which the driving field can be used to switch the topological character of the edge states, as measured by the Zak phase. Our results demonstrate how to induce long range transfer of strongly correlated particles by tuning both topology and driving. PMID:26932406

  5. Bioequivalence study of 8 mg ondansetron film-coated tablets in healthy Caucasian volunteers.

    PubMed

    Rudzki, P J; Kaza, M; Leś, A; Gilant, E; Ksycińska, H; Serafin-Byczak, K; Troć, M; Raszek, J; Piątkowska-Chabuda, E; Skowrońska-Smolak, M; Tarasiuk, A; Wilkowska, E; Łazowski, T

    2014-04-01

    The aim of the study was to investigate the bioequivalence of a generic product of 8 mg film-coated tablets (test) to the branded product (reference) at the same strength in order to apply for regulatory approval. The secondary objective of the study was to compare the tolerability of both products. A double blinded, randomized, cross-over, 2-period, comparative study was conducted in healthy Caucasian volunteers under fasting conditions. A single oral dose administration of the test or reference product was followed by a 7-day wash-out period. The ondansetron concentration was determined using a validated high performance liquid chromatography with a UV detection method. The 90% confidence interval of the point estimate (test over reference products) for C(max) and AUC(0-t) fell within the 80.00-125.00% acceptance range. The results of the study indicate that the film-coated tablets of Ondatron 8 mg manufactured by Tarchomińskie Zakłady Farmaceutyczne Polfa S.A. (test product) are bioequivalent to those of Zofran manufactured by GlaxoSmithKline Export Ltd (reference product). Both products were well tolerated. PMID:24132707

  6. Continuum regularization of quantum field theory

    SciTech Connect

    Bern, Z.

    1986-01-01

    Breit, Gupta, and Zaks made the first proposal for new gauge invariant nonperturbative regularization. The scheme is based on smearing in the fifth-time of the Langevin equation. An analysis of their stochastic regularization scheme for the case of scalar electrodynamics with the standard covariant gauge fixing is given. Their scheme is shown to preserve the masslessness of the photon and the tensor structure of the photon vacuum polarization at the one-loop level. Although stochastic regularization is viable in one-loop electrodynamics, difficulties arise which, in general, ruins the scheme. A successful covariant derivative scheme is discussed which avoids the difficulties encountered with the earlier stochastic regularization by fifth-time smearing. For QCD the regularized formulation is manifestly Lorentz invariant, gauge invariant, ghost free and finite to all orders. A vanishing gluon mass is explicitly verified at one loop. The method is designed to respect relevant symmetries, and is expected to provide suitable regularization for any theory of interest.

  7. Continuum regularization of quantum field theory

    SciTech Connect

    Bern, Z.

    1986-04-01

    Possible nonperturbative continuum regularization schemes for quantum field theory are discussed which are based upon the Langevin equation of Parisi and Wu. Breit, Gupta and Zaks made the first proposal for new gauge invariant nonperturbative regularization. The scheme is based on smearing in the ''fifth-time'' of the Langevin equation. An analysis of their stochastic regularization scheme for the case of scalar electrodynamics with the standard covariant gauge fixing is given. Their scheme is shown to preserve the masslessness of the photon and the tensor structure of the photon vacuum polarization at the one-loop level. Although stochastic regularization is viable in one-loop electrodynamics, two difficulties arise which, in general, ruins the scheme. One problem is that the superficial quadratic divergences force a bottomless action for the noise. Another difficulty is that stochastic regularization by fifth-time smearing is incompatible with Zwanziger's gauge fixing, which is the only known nonperturbaive covariant gauge fixing for nonabelian gauge theories. Finally, a successful covariant derivative scheme is discussed which avoids the difficulties encountered with the earlier stochastic regularization by fifth-time smearing. For QCD the regularized formulation is manifestly Lorentz invariant, gauge invariant, ghost free and finite to all orders. A vanishing gluon mass is explicitly verified at one loop. The method is designed to respect relevant symmetries, and is expected to provide suitable regularization for any theory of interest. Hopefully, the scheme will lend itself to nonperturbative analysis. 44 refs., 16 figs.

  8. Consistent Perturbative Fixed Point Calculations in QCD and Supersymmetric QCD.

    PubMed

    Ryttov, Thomas A

    2016-08-12

    We suggest how to consistently calculate the anomalous dimension γ_{*} of the ψ[over ¯]ψ operator in finite order perturbation theory at an infrared fixed point for asymptotically free theories. If the n+1 loop beta function and n loop anomalous dimension are known, then γ_{*} can be calculated exactly and fully scheme independently in a Banks-Zaks expansion through O(Δ_{f}^{n}), where Δ_{f}=N[over ¯]_{f}-N_{f}, N_{f} is the number of flavors, and N[over ¯]_{f} is the number of flavors above which asymptotic freedom is lost. For a supersymmetric theory, the calculation preserves supersymmetry order by order in Δ_{f}. We then compute γ_{*} through O(Δ_{f}^{2}) for supersymmetric QCD in the dimensional reduction scheme and find that it matches the exact known result. We find that γ_{*} is astonishingly well described in perturbation theory already at the few loops level throughout the entire conformal window. We finally compute γ_{*} through O(Δ_{f}^{3}) for QCD and a variety of other nonsupersymmetric fermionic gauge theories. Small values of γ_{*} are observed for a large range of flavors. PMID:27563948

  9. Geomorphological indicators of coseismic and extreme-rainfall slope instabilities in alpine settings (New Zealand, China, Taiwan)

    NASA Astrophysics Data System (ADS)

    Raab, Theresa; Leith, Kerry; Krautblatter, Michael

    2016-04-01

    Wenchuan and progressive slope failure in Taiwan in the years following the events. Interestingly, we find that coseismically induced landslides follow normal trends with respect to slope gradient, whereas slope failures during typhoon Morakot preferentially occurred on steeper slopes than during weak typhoons. In the regions of the 2003 and 2007 earthquakes in Fiordland, as well as in the region of the Wenchuan earthquake, landslide orientation does not suggest enhanced susceptibility due to topographic amplification of oblique incoming seismic waves, and may instead reflect the dependence of weathering and soil production on slope aspect. Slope aspect preference is highly variable in Taiwan, and dependent on wind directions during typhoons. While we cannot account for correlations between sensitivity and landslide occurrence during heavy rainfall events, we identify a noticeable increase in landslide occurrence with increasing sensitivity during seismic shaking. Additionally, landslide rates were found to remain elevated for 1 year, 2 years and 5 years, after typhoon Morakot, the 2003 Fiordland earthquake and the 2008 Wenchuan earthquake, respectively. However, further research needs to be carried out on this newly developed technique of identifying and analyzing slope failures using a global treeloss catalogue. Hansen, M.C., Potapov, P.V., Moore, R., Hancher, M., Turubanova, S.A., Tyukavina, A., Thau, D., Stehman, S. V., Goetz, S.J., Loveland, T.R., Kommareddy, A., Egorov, A., Chini, L., Justice, C.O. & Townshend, J.R.G. (2013): High-Resolution Global Maps of 21st-Century Forest Cover Change. - Science, 342: 850-853.

  10. The Cost-Optimal Distribution of Wind and Solar Generation Facilities in a Simplified Highly Renewable European Power System

    NASA Astrophysics Data System (ADS)

    Kies, Alexander; von Bremen, Lüder; Schyska, Bruno; Chattopadhyay, Kabitri; Lorenz, Elke; Heinemann, Detlev

    2016-04-01

    . "Investigation of balancing effects in long term renewable energy feed-in with respect to the transmission grid." Advances in Science and Research 12.1 (2015): 91-95, doi:10.5194/asr-12-91-2015 [2] Heide, Dominik, et al. "Reduced storage and balancing needs in a fully renewable European power system with excess wind and solar power generation." Renewable Energy 36.9 (2011): 2515-2523 [3] Rodriguez, R.A.: Weather-driven power transmission in a highly renewable European electricity network, PhD Thesis, Aarhus University, November 2014 [4] Pfluger, B. et al.: Tangible ways towards climate protection in the European Union (EU long-term scenarios 2050), Fraunhofer ISI, Karlsruhe, September 2011

  11. Interstellar Methanol from the Lab to Protoplanetary Disks

    NASA Astrophysics Data System (ADS)

    Drozdovskaya, Maria; Walsh, Catherine; Visser, Ruud; Harsono, Daniel; van Dishoeck, Ewine

    2015-08-01

    Interstellar methanol is considered to be a parent species of larger, more complex organic molecules. It holds a central role in many astrochemical models [e.g. 1]. Methanol has also been the focus of several laboratory studies [e.g. 2, 3] in an effort to gain insight into grain-surface chemistry, which potentially builds chemical complexity already in the cold, dark phases of protostellar evolution. The case of methanol is a prime example of experimental work having implications on astronomical scales. For this meeting, I would like to highlight how physical and chemical models can be unified to simulate infalling material during the birth of a low-mass protostar. An axisymmetric 2D semi-analytic collapse model [4], wavelength-dependent radiative transfer calculations with RADMC3D [5] and a comprehensive gas-grain chemical network [6] are used to study two physical scenarios. In the first case, the dominant disc growth mechanism is viscous spreading, while in the second, continuous infall of matter prevails. The results show that the infall path influences the abundance of methanol entering each type of disk, ranging from complete loss of methanol to an enhancement by a factor of >1 relative to the prestellar phase [7]. This work illustrates how the experimentally verified hydrogenation sequence of carbon monoxide leading to methanol influences the delivery of methanol ice to the planet- and comet-forming zones of protoplanetary disks. Such intriguing links will soon be tested by upcoming cometary data from the Rosetta mission and ALMA observations.[1] Garrod R. T., Herbst E., 2006, A&A, 457, 927[2] Watanabe N., Nagaoka A., Shiraki T., Kouchi A., 2004, ApJ, 616, 638[3] Fuchs G. W., Cuppen H. M., Ioppolo S., Romanzin C., Bisschop S. E., Andersson S., van Dishoeck E. F., Linnartz H., 2009, A&A, 505, 629[4] Visser R., van Dishoeck E. F., Doty S. D., Dullemond C. P., 2009, A&A, 495, 881[5] Dullemond C. P., Dominik C., 2004, A&A, 417, 159[6] Walsh C., Millar T. J

  12. Midplane Ices in the Embedded Phase

    NASA Astrophysics Data System (ADS)

    Drozdovskaya, Maria; Walsh, Catherine; van Dishoeck, Ewine

    2015-08-01

    Icy grains in the midplanes of the youngest protoplanetary disks are the building blocks of protoplanets and protocometary bodies. Our Solar System shows significant chemical diversity. The chemical content is thought to be either inherited from the initial prestellar cloud, out of which our Solar System formed, or formed in-situ during the subsequent evolution of the protoplanetary disk. In this poster, the chemical analysis of midplanes in the context of globally evolving and collapsing star-forming systems will be presented. Previous studies compared various solid species relative to water ice in comets and towards young protostars [e.g., 1, 2, 3]. It remains unclear whether the overlap in abundances is just a coincidence or whether the origins of cometary ices are that of a prestellar cloud. For this work, an axisymmentric 2D semi-analytic collapse model [4], wavelength-dependent radiative transfer calculations with RADMC3D [5] and a comprehensive gas-grain chemical network [6] are used to pin down ice abundances in a midplane. The methanol content of protoplanetary disks will be presented [7], but also that of other main ice components, such as water, carbon monoxide and carbon dioxide [8]. Our models can be used to probe the validity of theories on the origin of chemical complexity and also to access the degree of processing upon inheritance into the forming disk.[1] Öberg K. I., Boogert A. C. A., Pontoppidan K. M., van den Broek S., van Dishoeck E. F., Bottinelli S., Blake G. A., Evans, II N. J., 2011, ApJ, 740, 109[2] Mumma M. J., Charnley S. B., 2011, ARA&A, 49, 471[3] Bockelée-Morvan D. et al., 2000, A&A, 353, 1101[4] Visser R., van Dishoeck E. F., Doty S. D., Dullemond C. P., 2009, A&A, 495, 881[5] Dullemond C. P., Dominik C., 2004, A&A, 417, 159[6] Walsh C., Millar T. J., Nomura H., Herbst E., Widicus Weaver S., Aikawa Y., Laas J. C., Vasyunin A. I., 2014, A&A, 563, A33[7] Drozdovskaya M. N., Walsh C., Visser R., Harsono D., van Dishoeck E. F., 2014

  13. A Complex Organic Slushy Bathing Low-Mass Protostars

    NASA Astrophysics Data System (ADS)

    Drozdovskaya, Maria; Walsh, Catherine; Visser, Ruud; Harsono, Daniel; van Dishoeck, Ewine

    2015-08-01

    Complex organic molecules are ubiquitous companions of young forming stars. They were first observed in hot cores surrounding high-mass protostars [e.g., 1], but have since also been detected in the environs of several low-mass counterparts [e.g., 2]. Recent studies have shown that colder envelopes and positions with impinging outflows may also glow with emission from complex organic species [e.g., 3, 4]. For this meeting, I would like to present physicochemical modeling results on the synthesis of complex organics in an envelope-cavity system that is subject to non-thermal processing. This includes wavelength-dependent radiative transfer calculations with RADMC [5] and a comprehensive gas-grain chemical network [6]. The results show that the morphology of such a system delineates three distinct regions: the cavity wall layer with time-dependent and species-variant enhancements; a torus rich in complex organic ices, but not reflected in gas-phase abundances; and the remaining outer envelope abundant in simpler solid and gaseous molecules. Within the adopted paradigm, complex organic molecules are demonstrated to have unique lifetimes and be grouped into early and late species [7]. Key chemical processes for forming and destroying complex organic molecules will be discussed. In addition, the results of adding newly experimentally verified routes [8] into the existing chemical networks will be shown.[1] Blake G. A., Sutton E. C., Masson C. R., Phillips T. G., 1987, ApJ, 315, 621[2] Jørgensen J. K., Favre C., Bisschop S. E., Bourke T. L., van Dishoeck E. F., Schmalzl M., 2012, ApJ, 757, L4[3] Arce H. G., Santiago-García J., Jørgensen J. K., Tafalla M., Bachiller R., 2008, ApJ, 681, L21[4] Öberg K. I., Bottinelli S., Jørgensen J. K., van Dishoeck E. F., 2010, ApJ, 716, 825[5] Dullemond C. P., Dominik C., 2004, A&A, 417, 159[6] Walsh C., Millar T. J., Nomura H., Herbst E., Widicus Weaver S., Aikawa Y., Laas J. C., Vasyunin A. I., 2014, A&A, 563, A33[7] Drozdovskaya

  14. Residence time of suspended particles in the Garonne River (SW France): indications derived from Th-234, Be-7 and Pb-210

    NASA Astrophysics Data System (ADS)

    Schmidt, Sabine; Saari, Hanna-Kaïsa

    2013-04-01

    -temporal variations. Temporal changes in Th-234/Pb-210 and 7Be/210Pb activity ratios (ARs) are complex, depending on river discharge and suspended matter load. To derive sediment ages from the present dataset, two distinct models have been used: 1/ based on radionuclide budget (Dominik et al, 1987, Earth Planet. Sci. Lett. 84 165-180), and 2/ using Be-7/Pb-210 ARs (Matisoff et al, 2005, Earth Surf. Process. Landforms 30 1191-1201). These age estimates will be detailed in order to discuss particulate transport processes in the Garonne river during contrasted hydrological periods (flood and low waters).

  15. PEGASUS - An Austrian Nanosatellite for QB50

    NASA Astrophysics Data System (ADS)

    Scharlemann, Carsten; Seifert, Bernhard; Kohl, Dominik; Birschitzky, David; Gury, Lionel; Kerschbaum, Franz; Obertscheider, Christof; Ottensamer, Roland; Reissner, Alexander; Riel, Thomas; Sypniewski, Richard; Taraba, Michael; Trausmuth, Robert; Turetschek, Thomas

    2015-04-01

    PEGASUS - An Austrian Nanosatellite for QB50 C. Scharlemann* David Birschitzky* Lionel Gury*, Franz Kerschbaum~, Dominik Kohl#, Christof Obertscheider*, Roland Ottensamer~, Alexander Reissner+, Thomas Riel#, B. Seifert+, Richard Sypniewski*, Michael Taraba?, Robert Trausmuth*, Thomas Turetschek?, …. (*)University of Applied Sciences Wiener Neustadt, Austria (+)FOTEC GmbH, Wiener Neustadt, Austria (+) Spaceteam, TU Wien, Austria (~) University Wien, Wien, Austria The QB50 project is an international project with the goal to send up to 50 Nanosatellites, a.k.a. CubeSat, into the Thermosphere. The scientific goal of this mission is to monitor over a period of up to nine months the prevailing conditions in this rather unknown part of Earth's atmosphere. Each of the 50 nanosatellites will be equipped with one of three possible scientific instruments: (i) a set of Langmuir probes, (ii) atomic oxygen measurement device, (iii) ion/neutral mass spectrometer. All satellites will be launched together and released in a string-of-pearls type fashion. It is predicted that the satellites will drift apart rather rapidly following the release. Therefore, the QB50 missions offers the possibility of a measurement grid in the thermosphere of unprecedented scope and accuracy. One of the satellites, named PEGASUS, is designed and build by a team of Austrian researches and students. PEGASUS will be equipped with the aforementioned Langmuir probes and will provide information about essential properties of the plasma in the thermosphere such as the electrontemperature and -density. In order to ensure the capability to collect and downlink the data over several months, PEGASUS requires about the same types of subsystems as one would find on large-scale satellites. This includes an attitude control system, an on-board computer, telecommunication devices, an electrical power systems allowing to harvest the solar power and either distribute or store it for later use, a thermal control system

  16. a New Generation Mining Head with Disc Tool of Complex Trajectory / GŁOWICA URABIAJĄCA Nowej Generacji Z NARZĘDZIAMI Dyskowymi O ZŁOŻONEJ Trajektorii

    NASA Astrophysics Data System (ADS)

    Gospodarczyk, Piotr; Kotwica, Krzysztof; Stopka, Grzegorz

    2013-12-01

    łowych warunkach pracy, ulegają przyspieszonemu zużyciu. Wpływa to na prędkość i koszty drążenia tych wyrobisk. W artykule przedstawiono opracowane w Katedrze MGPiT AGH Kraków nowe i innowacyjne rozwiązanie głowicy urabiającej, z narzędziami dyskowymi niesymetrycznymi o złożonej trajektorii, jako alternatywę dla standardowych organów frezujących. Opisano zalety zastosowanej metody urabiania z wykorzystaniem tzw. tylnego podcinaniaoraz zasadę budowy i pracy zaproponowanego rozwiązania przedmiotowej głowicy. Dla opracowania konstrukcji prototypowego egzemplarza tej głowicy koniecznym było określenie, na podstawie badań laboratoryjnych, założeń i wytycznych. Przedstawiono konstrukcję opracowanego specjalnego stanowiska laboratoryjnego do badania narzędzi dyskowych o złożonej trajektorii, założoną metodykę badawczą, przebieg badań oraz uzyskane wyniki. Analiza tych wyników umożliwiła określenie wyżej wymienionych założeń i wytycznych dla konstrukcji głowicy prototypowej. Na ich podstawie opracowano, we współpracy z Zakładami REMAG S.A. w Katowicach, projekt techniczny nowego rozwiązania głowicy, dostosowanej do zabudowy na ramieniu średniego kombajnu chodnikowego KR 150. Wykonany egzemplarz głowicy został poddany próbom na stanowisku badawczym na poligonie Zakładów REMAG i uzyskał pozytywne wyniki badań wstępnych.

  17. Verification of applicability of the Trimble RTX satellite technology with xFill function in establishing surveying control networks

    NASA Astrophysics Data System (ADS)

    Krzyżek, Robert

    2013-12-01

    The paper presents the results of real time measurements of test geodetic control network points using the RTK GPS and RTX Extended technologies. The Trimble RTX technology uses the xFill function, which enables real measurements without the need for constant connection with the ASG EUPOS system reference stations network. Comparative analyses of the results of measurements using the methods were performed and they were compared with the test control network data assumed to be error-free. Although the Trimble RTX technology is an innovative measurement method which is rarely used now, the possibilities it provides in surveying works, including building geodetic control networks, are satisfactory and it will certainly contribute to improving the organisation of surveying works. W pracy przedstawiono wyniki pomiarów w czasie rzeczywistym punktów osnowy testowej z wykorzystaniem technologii RTK GPS oraz RTX Extended. W technologii Trimble RTX wykorzystano funkcję xFill, która daje możliwości realnego wykonywania pomiaru bez konieczności stałej łączności z siecią stacji referencyjnych systemu ASG EUPOS. Wykonano analizy porównawcze wyników pomiaru między metodami oraz odniesiono je do danych osnowy testowej, przyjętych za bezbłędne. Choć technologia Trimble RTX jest innowacyjną metodą pomiaru i jeszcze rzadko stosowaną, to możliwości jakie daje w realizacjach prac geodezyjnych, w tym zakładaniu osnów pomiarowych, są bardzo zadawalające i z pewnością przyczyni się do jeszcze lepszej i bardziej ekonomicznej organizacji prac geodezyjnych.

  18. Activation of the Classical Mitogen-Activated Protein Kinases Is Part of the Shiga Toxin-Induced Ribotoxic Stress Response and May Contribute to Shiga Toxin-Induced Inflammation

    PubMed Central

    Ahluwalia, Amrita; Schimmel, Jennifer J.; Rogers, Arlin B.; Leong, John M.; Thorpe, Cheleste M.

    2015-01-01

    Infection with enterohemorrhagic Escherichia coli (EHEC) can result in severe disease, including hemorrhagic colitis and the hemolytic uremic syndrome. Shiga toxins (Stx) are the key EHEC virulence determinant contributing to severe disease. Despite inhibiting protein synthesis, Shiga toxins paradoxically induce the expression of proinflammatory cytokines from various cell types in vitro, including intestinal epithelial cells (IECs). This effect is mediated in large part by the ribotoxic stress response (RSR). The Shiga toxin-induced RSR is known to involve the activation of the stress-activated protein kinases (SAPKs) p38 and JNK. In some cell types, Stx also can induce the classical mitogen-activated protein kinases (MAPKs) or ERK1/2, but the mechanism(s) by which this activation occurs is unknown. In this study, we investigated the mechanism by which Stx activates ERK1/2s in IECs and the contribution of ERK1/2 activation to interleukin-8 (IL-8) expression. We demonstrate that Stx1 activates ERK1/2 in a biphasic manner: the first phase occurs in response to StxB1 subunit, while the second phase requires StxA1 subunit activity. We show that the A subunit-dependent ERK1/2 activation is mediated through ZAK-dependent signaling, and inhibition of ERK1/2 activation via the MEK1/2 inhibitors U0126 and PD98059 results in decreased Stx1-mediated IL-8 mRNA. Finally, we demonstrate that ERK1/2 are activated in vivo in the colon of Stx2-intoxicated infant rabbits, a model in which Stx2 induces a primarily neutrophilic inflammatory response. Together, our data support a role for ERK1/2 activation in the development of Stx-mediated intestinal inflammation. PMID:26483408

  19. Best Practice Guide for the Treatment of Nightmare Disorder in Adults

    PubMed Central

    Aurora, R. Nisha; Zak, Rochelle S.; Auerbach, Sanford H.; Casey, Kenneth R.; Chowdhuri, Susmita; Karippot, Anoop; Maganti, Rama K.; Ramar, Kannan; Kristo, David A.; Bista, Sabin R.; Lamm, Carin I.; Morgenthaler, Timothy I.

    2010-01-01

    Summary of Recommendations: Prazosin is recommended for treatment of Posttraumatic Stress Disorder (PTSD)-associated nightmares. Level A Image Rehearsal Therapy (IRT) is recommended for treatment of nightmare disorder. Level A Systematic Desensitization and Progressive Deep Muscle Relaxation training are suggested for treatment of idiopathic nightmares. Level B Venlafaxine is not suggested for treatment of PTSD-associated nightmares. Level B Clonidine may be considered for treatment of PTSD-associated nightmares. Level C The following medications may be considered for treatment of PTSD-associated nightmares, but the data are low grade and sparse: trazodone, atypical antipsychotic medications, topiramate, low dose cortisol, fluvoxamine, triazolam and nitrazepam, phenelzine, gabapentin, cyproheptadine, and tricyclic antidepressants. Nefazodone is not recommended as first line therapy for nightmare disorder because of the increased risk of hepatotoxicity. Level C The following behavioral therapies may be considered for treatment of PTSD-associated nightmares based on low-grade evidence: Exposure, Relaxation, and Rescripting Therapy (ERRT); Sleep Dynamic Therapy; Hypnosis; Eye-Movement Desensitization and Reprocessing (EMDR); and the Testimony Method. Level C The following behavioral therapies may be considered for treatment of nightmare disorder based on low-grade evidence: Lucid Dreaming Therapy and Self-Exposure Therapy. Level C No recommendation is made regarding clonazepam and individual psychotherapy because of sparse data. Citation: Aurora RN; Zak RS; Auerbach SH; Casey KR; Chowduri S; Krippot A; Maganti RK; Ramar K; Kristo DA; Bista SR; Lamm CI; Morgenthaler TI. Best practice guide for the treatment of nightmare disorder in adults. J Clin Sleep Med 2010;6(4):389-401. PMID:20726290

  20. Single-stranded DNA-binding proteins PURalpha and PURbeta bind to a purine-rich negative regulatory element of the alpha-myosin heavy chain gene and control transcriptional and translational regulation of the gene expression. Implications in the repression of alpha-myosin heavy chain during heart failure.

    PubMed

    Gupta, Madhu; Sueblinvong, Viranuj; Raman, Jai; Jeevanandam, Valluvan; Gupta, Mahesh P

    2003-11-01

    The alpha-myosin heavy chain is a principal molecule of the thick filament of the sarcomere, expressed primarily in cardiac myocytes. The mechanism for its cardiac-restricted expression is not yet fully understood. We previously identified a purine-rich negative regulatory (PNR) element in the first intron of the gene, which is essential for its cardiac-specific expression (Gupta, M., Zak, R., Libermann, T. A., and Gupta, M. P. (1998) Mol. Cell. Biol. 18, 7243-7258). In this study we cloned and characterized muscle and non-muscle factors that bind to this element. We show that two single-stranded DNA-binding proteins of the PUR family, PURalpha and PURbeta, which are derived from cardiac myocytes, bind to the plus strand of the PNR element. In functional assays, PURalpha and PURbeta repressed alpha-myosin heavy chain (alpha-MHC) gene expression in the presence of upstream regulatory sequences of the gene. However, from HeLa cells an Ets family of protein, Ets-related protein (ERP), binds to double-stranded PNR element. The ERP.PNR complex inhibited the activity of the basal transcription complex from homologous as well as heterologous promoters in a PNR position-independent manner, suggesting that ERP acts as a silencer of alpha-MHC gene expression in non-muscle cells. We also show that PUR proteins are capable of binding to alpha-MHC mRNA and attenuate its translational efficiency. Furthermore, we show robust expression of PUR proteins in failing hearts where alpha-MHC mRNA levels are suppressed. Together, these results reveal that (i) PUR proteins participate in transcriptional as well as translational regulation of alpha-MHC expression in cardiac myocytes and (ii) ERP may be involved in cardiac-restricted expression of the alpha-MHC gene by preventing its expression in non-muscle cells. PMID:12933792

  1. PREFACE: XXXth International Colloquium on Group Theoretical Methods in Physics (ICGTMP) (Group30)

    NASA Astrophysics Data System (ADS)

    Brackx, Fred; De Schepper, Hennie; Van der Jeugt, Joris

    2015-04-01

    participants at the Group30 colloquium from 46 different countries. This high number of participants makes the 30th edition of ICGTMP one of the most successful meetings of the series. We were particularly happy with the attendance of 32 students and many young postdocs: this is promising for the future of the research field and of the colloquium series. The attraction of young scientists was promoted by a reduced participation fee, the availability of cheap accommodation in the University Student Guest House, grants from a US-NSF project and grants from the Organising Committee supporting participants from countries with limited financial resources. The colloquium brought together international top researchers, with a variety of different backgrounds but with "group theoretical or algebraic methods" as common ground. The selection of plenary speakers and topics was made by the Organizing Committee, following the suggestions of the International Advisory Committee (consisting of prominent scientists in their domain), and ensuring the diversity of the subjects treated. There were 11 plenary talks, given as well by distinguished world experts as by young rising stars: Matthias Christandl, Alberto De Sole, Rui Loja Fernandes, François Gay-Balmaz, Gitta Kutyniok, Amiram Leviatan, Karl-Hermann Neeb, Christoph Schweigert, Yuji Tachikawa, Luc Vinet and Joshua Zak. Next to the plenary talks, there were 170 talks in six parallel sessions and 10 poster presentations. All scientific activities took place in the Joseph Plateau Building of the Faculty of Engineering and Architecture of Ghent University, a historical building conveniently located in the city centre of Ghent. In this building we could make use of the main lecture hall (400 seats) for the plenary lectures, six lecture rooms for parallel sessions, two offices for organizational activities and registrations, two PC-rooms and a large foyer for coffee breaks, book exhibitions and the poster session. As part of the colloquium, a

  2. Best Practice Guide for the Treatment of REM Sleep Behavior Disorder (RBD)

    PubMed Central

    Aurora, R. Nisha; Zak, Rochelle S.; Maganti, Rama K.; Auerbach, Sanford H.; Casey, Kenneth R.; Chowdhuri, Susmita; Karippot, Anoop; Ramar, Kannan; Kristo, David A.; Morgenthaler, Timothy I.

    2010-01-01

    Summary of Recommendations: Modifying the sleep environment is recommended for the treatment of patients with RBD who have sleep-related injury. Level A Clonazepam is suggested for the treatment of RBD but should be used with caution in patients with dementia, gait disorders, or concomitant OSA. Its use should be monitored carefully over time as RBD appears to be a precursor to neurodegenerative disorders with dementia in some patients. Level B Clonazepam is suggested to decrease the occurrence of sleep-related injury caused by RBD in patients for whom pharmacologic therapy is deemed necessary. It should be used in caution in patients with dementia, gait disorders, or concomitant OSA, and its use should be monitored carefully over time. Level B Melatonin is suggested for the treatment of RBD with the advantage that there are few side effects. Level B Pramipexole may be considered to treat RBD, but efficacy studies have shown contradictory results. There is little evidence to support the use of paroxetine or L-DOPA to treat RBD, and some studies have suggested that these drugs may actually induce or exacerbate RBD. There are limited data regarding the efficacy of acetylcholinesterase inhibitors, but they may be considered to treat RBD in patients with a concomitant synucleinopathy. Level C The following medications may be considered for treatment of RBD, but evidence is very limited with only a few subjects having been studied for each medication: zopiclone, benzodiazepines other than clonazepam, Yi-Gan San, desipramine, clozapine, carbamazepine, and sodium oxybate. Level C Citation: Aurora RN; Zak RS; Maganti RK; Auerbach SH; Casey KR; Chowdhuri S; Karippot A; Ramar K; Kristo DA; Morgenthaler TI. Best practice guide for the treatment of REM sleep behavior disorder (RBD). J Clin Sleep Med 2010;6(1):85-95. PMID:20191945

  3. Trace Element Condensation in Circumstellar Envelopes of Carbon Stars

    NASA Astrophysics Data System (ADS)

    Lodders, K.; Fegley, B., Jr.

    1992-07-01

    It is now well established that meteorites contain reduced presolar grains, such as graphite and silicon carbide (SiC), which are probably formed by condensation of dust in the circumstellar envelopes of carbon-rich AGB stars. Here we model condensation in envelopes of carbon stars, with an emphasis on trace elements. Since absolute elemental abundances in stellar atmospheres are generally not known, we assume solar abundances (Anders and Grevesse 1989), except for carbon. A C/O ratio of 2, consistent with the mean and median values of 2.1 and 1.8 respectively, for 61 carbon stars (Gow 1977) was used. The C/O ratio was increased by adding carbon because astrophysicists believe that carbon produced in helium-burning zones may be mixed to the surfaces of C stars (e.g. Lucy 1976). We used physical parameters for the circumstellar shell of the high mass-loss rate, prototypical carbon star IRC +10216 (e.g. Keady et al. 1988, Dominik et al. 1990) and theoretical considerations by Salpeter (1974a,b) to construct a P-T-model of the envelope (see Fig. 1). Thermodynamic equilibrium condensation calculations for a reduced gas include ~600 gaseous and solid compounds of the elements H, C, N, O, S, P, F, Cl, Fe, Mg, Al, Ti, Si, Ca, Zr, Hf, V, Nb, Ta, Cr, Mo, W, and REE. Refractory oxides, sulfides, nitrides, and carbides were considered as condensates. The calculations were done from T = 800 to 2500 K, and P= 10^-5 to 10^-13 bars. The effects of nucleation on condensation temperatures were calculated using the nucleation model discussed by Salpeter (1974a,b) and Cameron and Fegley (1982). The temperature drop required for condensation depends on (P,T, density) in the expanding envelope and also on the abundance, density, and surface energy (Es) of the nucleating compound. The range of E(sub)s values for NaCl-type carbides are about 800-1700 erg/cm^2 (Livey & Murray 1956); however, these data are generally poorly known. Another important variable is the sticking coefficient (s

  4. Black Holes Lead Galaxy Growth, New Research Shows

    NASA Astrophysics Data System (ADS)

    2009-01-01

    Astronomers may have solved a cosmic chicken-and-egg problem -- the question of which formed first in the early Universe -- galaxies or the supermassive black holes seen at their cores. "It looks like the black holes came first. The evidence is piling up," said Chris Carilli, of the National Radio Astronomy Observatory (NRAO). Carilli outlined the conclusions from recent research done by an international team studying conditions in the first billion years of the Universe's history in a lecture presented to the American Astronomical Society's meeting in Long Beach, California. Gas in Distant Galaxy VLA image (right) of gas in young galaxy seen as it was when the Universe was only 870 million years old. CREDIT: NRAO/AUI/NSF, SDSS Full-size JPEG, 323 KB PDF file, 180 KB Galaxy image, no annotation, JPEG 21 KB Earlier studies of galaxies and their central black holes in the nearby Universe revealed an intriguing linkage between the masses of the black holes and of the central "bulges" of stars and gas in the galaxies. The ratio of the black hole and the bulge mass is nearly the same for a wide range of galactic sizes and ages. For central black holes from a few million to many billions of times the mass of our Sun, the black hole's mass is about one one-thousandth of the mass of the surrounding galactic bulge. "This constant ratio indicates that the black hole and the bulge affect each others' growth in some sort of interactive relationship," said Dominik Riechers, of Caltech. "The big question has been whether one grows before the other or if they grow together, maintaining their mass ratio throughout the entire process." In the past few years, scientists have used the National Science Foundation's Very Large Array radio telescope and the Plateau de Bure Interferometer in France to peer far back in the 13.7 billion-year history of the Universe, to the dawn of the first galaxies. "We finally have been able to measure black-hole and bulge masses in several galaxies seen

  5. Impact of river regulation on potential sediment mobilization and transport in an Alpine catchment

    NASA Astrophysics Data System (ADS)

    Costa, Anna; Molnar, Peter; Lane, Stuart N.; Bakker, Maarten

    2015-04-01

    The upper Rhône basin (upstream of Lake Geneva) has been heavily affected by human activities during the last century. The most evident impacts are related to river regulation, specifically flow impoundement, flow abstraction and channelization. In the last century and mainly since 1960, several large dams have been built along the main tributaries of the Rhône River, resulting in the water storage of a volume equal to 20% of the total annual river flow. The dams are part of hydropower systems which abstract water from streams and transfer it through complex networks (intakes, tunnels and pumping stations) to the reservoirs. Hydropower production leads to regulated flow in the Rhône: mostly an increase of winter flows, a reduction of summer flows, and a decrease of flood peaks. The sediment supply into Lake Geneva has decreased following dam construction (Loizeau & Dominik, 2000) due to the storage of sediment in upstream reservoirs, in rivers with reduced sediment transport capacity due to flow abstraction, and due to the development of sediment mining. Our hypothesis is that streamflow regulation itself has dramatically impacted the sediment transport dynamics of the system. We investigate the impacts of flow regulation on the sediment transport regime, by analysing the effects on potential sediment transport capacity (bedload). By the use of different bedload transport formulae (Meyer-Peter Müller, Wilcock and Crowe), the potential sediment transport capacity is computed at different cross sections within the basin. Potential sediment mobility occurs when the applied bed shear stress exceeds a critical value, τ>τc. The applied bed shear stress is computed as τ=ρghS, with water depth (h) measured from rating curves. We obtain an estimate of the energy slope (S) from the analysis of the river cross section, assuming uniform flow. The critical value of bed shear stress τc is computed using empirical formulae as a function of the grain diameter (ds). To

  6. Spitzer spectroscopy of newly discovered clusters of star formation in Serpens

    NASA Astrophysics Data System (ADS)

    Merín, B.; Pontoppidan, K. M.; Geers, V. C.; Dullemond, C. P.; Harvey, P.; van Dishoeck, E. F.; Augereau, J. C.; Kessler, J.; Boogert, A. C. A.; C2d Team

    We have discovered a uniquely rich star-forming region covering 0.5 sq. degrees near the Serpens Core from IRAC/MIPS maps obtained with the Spitzer Space Telescope within the Cores to Disks (c2d) Legacy program. The region contains three clusters apparently at different evolutionary stages, suggesting that sequential star formation has taken place. A number of the sources in this sample has been observed with the IRS spectrometer and will be presented and analysed here in relation to the general evolutionary picture for the region. In particular, the spectra contain signatures of silicates allowing the detailed comparison of grain composition, crystallinity, size distribution as well as physical structure of the disks between illustrative objects in the region at different evolutionary stages. 1. Introduction Mounting evidence points to the period between 1 and 10 Myrs as the most probable time-scale for the evolution of the circumstellar disks around young stars and the possible formation of planets. For example, the inner hot dust as traced by near-infrared photometry has been found to disperse within 3-6 Myrs (Haish et al. 2001). The dust has also been observed to crystallize due to thermal annealing in the innermost parts followed by strong radial mixing (van Boekel et al. 2004). Mid-infrared spectra coupled with disk models indicate that disks evolve from a flared geometry to a flat self-shadowed geometry (Meeus et al. 2001), as grains grow and settle to the mid-plane (Dullemond & Dominik 2004). Most of these previous studies are based on spectra of a handful of objects spread across the sky. A better statistical picture of disk evolution can be obtained by comparing disk populations in different co-eval clusters. 2. New star forming clusters in Serpens As part of the Cores to Disks (c2d) Legacy mapping campaign of molecular clouds (Evans et al. 2003), we discovered a region of ~0.5 square degrees in the Serpens molecular cloud (d ~ 250 pc) that is very rich

  7. Technidilaton at the conformal edge

    SciTech Connect

    Hashimoto, Michio; Yamawaki, Koichi

    2011-01-01

    Technidilaton (TD) was proposed long ago in the technicolor near criticality/conformality. To reveal the critical behavior of TD, we explicitly compute the nonperturbative contributions to the scale anomaly <{theta}{sub {mu}}{sup {mu}>} and to the technigluon condensate <{alpha}G{sub {mu}{nu}}{sup 2}>, which are generated by the dynamical mass m of the technifermions. Our computation is based on the (improved) ladder Schwinger-Dyson equation, with the gauge coupling {alpha} replaced by the two-loop running coupling {alpha}({mu}) having the Caswell-Banks-Zaks infrared fixed point {alpha}{sub *}: {alpha}({mu}){approx_equal}{alpha}={alpha}{sub *} for the infrared region m<{mu}<{Lambda}{sub TC}, where {Lambda}{sub TC} is the intrinsic scale (analogue of {Lambda}{sub QCD} of QCD) relevant to the perturbative scale anomaly. We find that -<{theta}{sub {mu}}{sup {mu}}>/m{sup 4}{yields}const{ne}0 and <{alpha}G{sub {mu}}{nu}{sup 2}>/m{sup 4}{yields}({alpha}/{alpha}{sub cr}-1){sup -3/2}{yields}{infinity} in the criticality limit m/{Lambda}{sub TC}{approx}exp(-{pi}/({alpha}/{alpha}{sub cr}-1){sup 1/2}){yields}0 ({alpha}={alpha}{sub *}=>{alpha}{sub cr}, or N{sub f} approaches N{sub f}{sup cr}) ('conformal edge'). Our result precisely reproduces the formal identity <{theta}{sub {mu}}{sup {mu}>}=({beta}({alpha})/4{alpha}{sup 2})<{alpha}G{sub {mu}{nu}}{sup 2}>, where {beta}({alpha})={Lambda}{sub TC}({partial_derivative}{alpha}/{partial_derivative}{Lambda}{sub TC})=-(2{alpha}{sub cr}/{pi}){center_dot}({alpha}/{alpha}{sub cr}-1){sup 3/2} is the nonperturbative beta function corresponding to the above essential singularity scaling of m/{Lambda}{sub TC}. Accordingly, the partially conserved dilatation current implies (M{sub TD}/m){sup 2}(F{sub TD}/m){sup 2}=-4<{theta}{sub {mu}}{sup {mu}}>/m{sup 4}{yields}const{ne}0 at criticality limit, where M{sub TD} is the mass of TD and F{sub TD} the decay constant of TD. We thus conclude that at criticality limit the TD could become a ''true

  8. Results of the Promethee Method Application in Selecting the Technological System at the Majdan III Open Pit Mine / Wyniki Zastosowania Metody Promethee do Wyboru Systemu Technologicznego W Kopalni Odkrywkowej Majdan III

    NASA Astrophysics Data System (ADS)

    Vujić, Slobodan; Hudej, Marjan; Miljanović, Igor

    2013-12-01

    This paper discusses the application of the PROMETHEE model and the results achieved in practice, following the example of the multi-criteria selection of the technological system at the Majdan III clay mineral raw material open pit mine of the Potisje Company, Republic of Serbia. After the introduction comments, reasons are explained for selecting the new technological system, conditions and limitations for the seven alternative solutions considered are described, mathematical foundation for the PROMETHEE method and a multi-criteria model of the problem in question are presented. The solution with the following structure was ranked first and accepted by the Company management as the best: Bucket chain excavator - Conveyor belts - Spreader (ECS), alongside a decision is made on the acquisition of machinery and system construction. The system was put into operation in 2000. The experience and the data accumulated in the previous twelve years confirm that the decision made on the application of the ECS technology was just, and the conclusion lists the benefits achieved. W artykule omówiono zastosowanie modelu Promethee i przedyskutowano uzyskane w ten sposób wyniki na przykładzie wielokryterialnego wyboru systemu technologicznego do zastosowania w kopalni odkrywkowej minerałów ilastych Majdan III, należącej do przedsiębiorstwa górniczego Potisje (Republika Serbii). Po uwagach wprowadzających przedstawiono powody wyboru nowego ciągu technologicznego, omówiono warunki oraz ograniczenia dla siedmiu alternatywnych rozwiązań, podstawy matematyczne metody Promethee oraz wielokryterialny model zagadnienia. Rozwiązanie uznane za najlepsze i zaaprobowane przez zarząd przedsiębiorstwa zakłada zastosowanie następującego ciągu technologicznego: koparka łancuchowa jednonaczyniowa - przenośniki taśmowe - rozkładarka(system ECS). Podjęto także decyzje odnośnie zakupu sprzętu i instalacji systemu, który uruchomiony został w 2000 roku. Doświadczenia i

  9. Effect of destablized reactions using lithium amide (LiNH2) and doping using titanium based catalyst on the desorption characteristics of lithuim aluminium hydride (LiAlH4)

    NASA Astrophysics Data System (ADS)

    Paravasthu, Siddharth

    In the past few decades there has been a tremendous increase in hydrogen storage research. Numerous materials and material systems have been studied as potential candidates for hydrogen storage, but unfortunately none of those materials demonstrate enough hydrogen releasing capacity under suitable temperature range to be used for hydrogen storage. Research promises to unlock the potential of these materials and ultimately lead to the commercialization of this technology. LiAlH4 is one of those materials that have been exclusively studied as a candidate for hydrogen storage due to its high theoretical hydrogen storage capacity, and its ability to release hydrogen in more than one step at different temperature ranges. Jun Lu and Zhigang Zak Fang studied the effects of titanium based catalyst (TiCl3.1/3AlCl3) and destabilization reactions using LiNH2 on LiAlH4, but did not demonstrate the effects of ball milling on the system. In the present work we have investigated the effects of ball milling, and the effects of destabilization reaction using LiNH2 on the hydrogen release characteristics of LiAlH4 doped with TiCl3. The current market scenario for fuel cell technology and the possibility and consequences of introducing the current system in the market has been briefly discussed. X-ray powder diffraction, thermo-gravimetric analysis and scanning electron microscopy were employed for the characterization of the samples. Both the compounds LiNH2, and TiCl3 worked in effecting the dehydrogenation kinetics of LiAlH4. The duration of ball milling required to affect the dehydrogenation kinetics of LiAlH 4 using TiCl3 was optimized. A hydrogen release of 7.3 wt% was observed from the final system i.e. (LiAlH4 LiNH2 doped with 2% TiCl3) at temperatures below 400°C.

  10. The Treatment of Central Sleep Apnea Syndromes in Adults: Practice Parameters with an Evidence-Based Literature Review and Meta-Analyses

    PubMed Central

    Aurora, R. Nisha; Chowdhuri, Susmita; Ramar, Kannan; Bista, Sabin R.; Casey, Kenneth R.; Lamm, Carin I.; Kristo, David A.; Mallea, Jorge M.; Rowley, James A.; Zak, Rochelle S.; Tracy, Sharon L.

    2012-01-01

    CSAS. (OPTION)The use of zolpidem and triazolam may be considered for the treatment of primary CSAS only if the patient does not have underlying risk factors for respiratory depression. (OPTION)The following possible treatment options for CSAS related to end-stage renal disease may be considered: CPAP, supplemental oxygen, bicarbonate buffer use during dialysis, and nocturnal dialysis. (OPTION) Citation: Aurora RN; Chowdhuri S; Ramar K; Bista SR; Casey KR; Lamm CI; Kristo DA; Mallea JM; Rowley JA; Zak RS; Tracy SL. The treatment of central sleep apnea syndromes in adults: practice parameters with an evidence-based literature review and meta-analyses. SLEEP 2012;35(1):17-40. PMID:22215916

  11. Analytical singlet α{/s 4} QCD contributions into the e + e --annihilation Adler function and the generalized Crewther relations

    NASA Astrophysics Data System (ADS)

    Kataev, A. L.

    2012-02-01

    The generalized Crewther relations in the channels of the non-singlet and vector quark currents are considered. These relations follow from the double application of the operator product expansion approach to the same axial vector-vector-vector triangle amplitude in two regions, adjoining to the angle sides ( x, y) (or p 2, q 2). We assume that the generalized Crewther relations in these two kinematic regimes result in the existence of the same perturbation expression for two products of the coefficient functions of annihilation and deepinelastic scattering processes in the non-singlet and vector channels. This feature explains the conformal symmetry motivated cancellations between the singlet α{/s 3} corrections to the Gross-Llewellyn Smith sum rule S GLS of ν N deep inelastic scattering and the singlet α{/s 3} correction to the e + e --annihilation Adler function D {/A V } in the product of the corresponding perturbative series. Taking into account the Baikov-Chetyrkin-Kuhn fourth order result for S GLS and the perturbative effects of the violation of the conformal symmetry in the generalized Crewther relation, we obtain the analytical contribution to the singlet α{/s 4} correction to the D {/A V } function. Its a-posteriori comparison with the recent result of direct diagram-by-diagram evaluation of the singlet fourth order corrections to D {/A V } function demonstrates the coincidence of the predicted and obtained ζ{3/2}-contributions to the singlet term. They can be obtained in the conformal invariant limit from the original Crewther relation. Therefore, on the contrary to previous belief, the appearance of ζ3-terms in the perturbative series in quantum field theory gauge models does not contradict to the property of the conformal symmetry and can be considered as regular feature. The Banks-Zaks motivated relation between our predicted and the obtained directly fourth order corrections is mentioned. It confirms the expectation, previously made by Baikov

  12. Walking on the ladder: 125 GeV technidilaton, or Conformal Higgs

    NASA Astrophysics Data System (ADS)

    Matsuzaki, Shinya; Yamawaki, Koichi

    2015-12-01

    The walking technicolor based on the ladder Schwinger-Dyson gap equation is studied, with the scale-invariant coupling being an idealization of the Caswell-Banks-Zaks infrared fixed point in the "anti-Veneziano limit", such that N C → ∞ with N C · α( μ 2) = fixed and N F / N C = fixed (≫1), of the SU( N C ) gauge theory with massless N F flavors near criticality. We show that the 125 GeV Higgs can be naturally identified with the technidilaton (TD) predicted in the walking technicolor, a pseudo Nambu-Goldstone (NG) boson of the spontaneous symmetry breaking of the approximate scale symmetry. Ladder calculations yield the TD mass M ϕ from the trace anomaly as {M}_{φ}^2{F}_{φ}^2=-4<{θ}_{μ}^{μ}> =-β (α ({μ}^2))/α ({μ^2)}< {G}_{λ ν}^2({μ}^2)> ˜eq {N}_C{N}_F16/π^4{m}_F^4 , independently of the renormalization point μ, where m F is the dynamical mass of the technifermion, and {F}_{φ }=O(√{N_F{N}_C}{m}_F) the TD decay constant. It reads {M}_{φ}^2˜eq {(\\upsilon_{EW}/2\\cdot 5{\\upsilon}_{EW}/F_{φ })}^2\\cdot [8/N_F4/N_C],({\\upsilon}_{EW}=246GeV) , which implies F ϕ ≃ 5 v EW for M ϕ ≃ 125 GeV ≃ 1/2 v EW in the one-family model ( N C = 4 , N F = 8), in good agreement with the current LHC Higgs data. The result reflects a generic scaling M ϕ 2 / υ EW 2 ˜ M ϕ 2 / F ϕ 2 ˜ m F 2 / F ϕ 2 ˜ 1/( N F N C ) → 0 as a vanishing trace anomaly, namely the TD has a mass vanishing in the anti-Veneziano limit, similarly to η' meson as a pseudo-NG boson of the ordinary QCD with vanishing U(1) A anomaly in the Veneziano limit ( N F / N C ≪ 1).

  13. Regional model studies of the atmospheric dispersion of fine volcanic ash after the eruption of Eyjafjallajoekull

    NASA Astrophysics Data System (ADS)

    Langmann, B.; Hort, M. K.

    2010-12-01

    During the eruption of Eyjafjallajoekull on Iceland in April/May 2010 air traffic over Europe was repeatedly interrupted because of volcanic ash in the atmosphere. This completely unusual situation in Europe leads to the demand of improved crisis management, e.g. European wide regulations of volcanic ash thresholds and improved forecasts of theses thresholds. However, the quality of the forecast of fine volcanic ash concentrations in the atmosphere depends to a great extent on a realistic description of the erupted mass flux of fine ash particles, which is rather uncertain. Numerous aerosol measurements (ground based and satellite remote sensing, and in situ measurements) all over Europe have tracked the volcanic ash clouds during the eruption of Eyjafjallajoekull offering the possibility for an interdisciplinary effort between volcanologists and aerosol researchers to analyse the release and dispersion of fine volcanic ash in order to better understand the needs for realistic volcanic ash forecasts. This contribution describes the uncertainties related to the amount of fine volcanic ash released from Eyjafjallajoekull and its influence on the dispersion of volcanic ash over Europe by numerical modeling. We use the three-dimensional Eulerian atmosphere-chemistry/aerosol model REMOTE (Langmann et al., 2008) to simulate the distribution of volcanic ash as well as its deposition after the eruptions of Eyjafjallajoekull during April and May 2010. The model has been used before to simulate the fate of the volcanic ash after the volcanic eruptions of Kasatochi in 2008 (Langmann et al., 2010) and Mt. Pinatubo in 1991. Comparing our model results with available measurements for the Eyjafjallajoekull eruption we find a quite good agreement with available ash concentrations data measured over Europe as well as with the results from other models. Langmann, B., K. Zakšek and M. Hort, Atmospheric distribution and removal of volcanic ash after the eruption of Kasatochi volcano

  14. Oxygen Isotope Perspectives on Magma Sources and Pluton Assembly in Convergent Margin Batholiths

    NASA Astrophysics Data System (ADS)

    Lackey, J.

    2008-12-01

    hierarchy of magma systems operated in the SNB and that sources were periodically reset by tectonic modification. [1] Lackey et al. 2008, J. Pet. [2] Coleman et el. 2004 Geol.; [3] Zak et al. 2007, GSAB.; [4] Matzel et al. 2007, GCA; [5] Ducea, 2001, GSA Today

  15. Use of Cad Systems in Testing the Collision of Underground Transportation Means / Zastosowanie systemów Cad w badaniach kolizyjności środków transportu podziemnego

    NASA Astrophysics Data System (ADS)

    Dudek, Marek

    2013-06-01

    A concept of use of CAD systems in testing collision of underground transportation means is presented. Reasons for undertaking this problem are given with end users identified. The concept of the system for collision analyses of transported loads is described. Examples of collision analysis during transportation of powered roof support are given. Presented system is designed to aid planning, organizational and training activities undertaken in management of transportation safety in mines. It will be also possible to use software resources, developed within the system as the didactic material as regards safe transportation process, which include hazards to the employees working in the area of transportation operations. Developed prototype of a system for testing the collision of underground transportation means was positively assessed by employees of the Coal Company, JSC - industrial partner of KOMAG. This prototype is continuously improved and adapted for commercial implementation in the selected coal mines. W pracy przedstawiono koncepcję zastosowania systemów CAD w badaniach kolizyjności środków transportu podziemnego. Określono przyczyny podjęcia tematu oraz zidentyfikowano końcowych użytkowników. Zaprezentowano koncepcję systemu do analiz kolizyjności transportowanych ładunków. Pokazano przykłady analizy kolizyjności podczas transportu sekcji obudowy zmechanizowanej. Przedstawiony system przeznaczony jest do wspomagania działań planistycznych, organizacyjnych i szkoleniowych podejmowanych w zarządzaniu bezpieczeństwem transportu w zakładach górniczych. Opracowane w ramach systemu zasoby programowe będzie można również wykorzystać jako materiał dydaktyczny z zakresu bezpieczeństwa pracy w transporcie, uwzględniający zagrożenia dla pracowników pracujących w bezpośredniej strefie prac transportowych. Opracowany prototyp systemu do badania kolizyjności środków transportu podziemnego został pozytywnie oceniony przez pracownik

  16. Underground Lead-Zinc Mine Production Planning Using Fuzzy Stochastic Inventory Policy / Planowanie Wydobycia Cynku I Ołowiu W Kopalniach Podziemnych Z Wykorzystaniem Podejścia Stochastycznego Z Elementami Logiki Rozmytej Do Określania Niezbędnego Poziomu Zapasów

    NASA Astrophysics Data System (ADS)

    Gligoric, Zoran; Beljic, Cedomir; Gluscevic, Branko; Cvijovic, Cedomir

    2015-03-01

    Methodology for long-term underground lead-zinc mine planning based on fuzzy inventory theory is presented in this paper. We developed a fuzzy stochastic model of inventory control problem for planning lead-zinc ore production under uncertainty. The final purpose of this article is to find the optimal quantity of mined ore that should be stockpiled, in order to enable "feeding" of mineral processing plant in cases when the production in underground mine is interrupted, by using Possibilistic mean value of fuzzy number for defuzzing the fuzzy total annual inventory costs, and by using Extension of the Lagrangean method for solving inequality constrain problem. The different types of costs involved in mined ore inventory problems affect the efficiency of production scheduling. Dynamic nature of lead and zinc metal price is described by Ornstein-Uhlenbeck stochastic mean reverting process. The model is illustrated with a numerical example. W pracy przedstawiono metodologię długoterminowego wydobycia cynku i ołowiu w kopalniach podziemnych z wykorzystaniem podejścia stochastycznego z elementami logiki rozmytej do określania wymaganego poziomu zapasów. Opracowaliśmy model stochastyczny z wykorzystaniem elementów logiki rozmytej do kontroli zapasów w planowaniu wydobycia cynku i ołowiu w warunkach niepewności. Celem końcowym pracy jest określenie optymalnej ilości wydobywanej rudy, którą należy zachować jako zapas tak aby zapewnić odpowiednie jej dostawy do zakładu przeróbczego nawet w przypadku przerwania wydobycia w kopalni podziemnej, opierając się na posybilistycznej wartości średniej liczby rozmytej i wyostrzeniu całkowitych rocznych kosztów zapasów. Wykorzystano także rozszerzenie metody Lagrange'a do rozwiązywania problemu więzów w nierówności. Różnorakie koszty związane ze składowaniem zapasów wydobywanej rudy mają wpływ na wydajność planowanej produkcji. Dynamiczne zmiany cen cynku i o

  17. PREFACE: Nano- and microfluidics Nano- and microfluidics

    NASA Astrophysics Data System (ADS)

    Jacobs, Karin

    2011-05-01

    compressible fluids Kerstin Falk and Klaus Mecke Wetting, roughness and flow boundary conditions Olga I Vinogradova and Aleksey V Belyaev Molecular transport and flow past hard and soft surfaces: computer simulation of model systems F Léonforte, J Servantie, C Pastorino, and M Müller Simulations of slip flow on nanobubble-laden surfaces J Hyväluoma, C Kunert and J Harting Electrophoretic transport of biomolecules across liquid-liquid interfaces Thomas Hahn, Götz Münchow and Steffen Hardt Wetting morphologies and their transitions in grooved substrates Ralf Seemann, Martin Brinkmann, Stephan Herminghaus, Krishnacharya Khare, Bruce M Law, Sean McBride, Konstantina Kostourou, Evgeny Gurevich, Stefan Bommer, Carsten Herrmann and Dominik Michler Imbibition in mesoporous silica: rheological concepts and experiments on water and a liquid crystal Simon Gruener, and Patrick Huber Theory and simulations of water flow through carbon nanotubes: prospects and pitfalls Douwe Jan Bonthuis, Klaus F Rinne, Kerstin Falk, C Nadir Kaplan, Dominik Horinek, A Nihat Berker, Lydéric Bocquet, and Roland R Netz Structure and flow of droplets on solid surfaces P Müller-Buschbaum, D Magerl, R Hengstler, J-F Moulin, V Körstgens, A Diethert, J Perlich, S V Roth, M Burghammer, C Riekel, M Gross, F Varnik, P Uhlmann, M Stamm, J M Feldkamp and C G Schroer Stability and dynamics of droplets on patterned substrates: insights from experiments and lattice Boltzmann simulations F Varnik, M Gross, N Moradi, G Zikos, P Uhlmann, P Müller-Buschbaum, D Magerl, D Raabe, I Steinbach and M Stamm Micro-capsules in shear flow R Finken, S Kessler and U Seifert Micro-rheology on (polymer-grafted) colloids using optical tweezers C Gutsche, M M Elmahdy, K Kegler, I Semenov, T Stangner, O Otto, O Ueberschär, U F Keyser, M Krueger, M Rauscher, R Weeber, J Harting, Y W Kim, V Lobaskin, R R Netz, and F Kremer Dynamics of colloids in confined geometries L Almenar and M Rauscher Dynamics of red blood cells and vesicles in

  18. Practice Parameters for the Clinical Evaluation and Treatment of Circadian Rhythm Sleep Disorders

    PubMed Central

    Morgenthaler, Timothy I.; Lee-Chiong, Teofilo; Alessi, Cathy; Friedman, Leah; Aurora, R. Nisha; Boehlecke, Brian; Brown, Terry; Chesson, Andrew L.; Kapur, Vishesh; Maganti, Rama; Owens, Judith; Pancer, Jeffrey; Swick, Todd J.; Zak, Rochelle

    2007-01-01

    the diagnosis of FRD in sighted and unsighted patients but there is insufficient evidence to recommend their routine use in the diagnosis of SWD, JLD, ASPD, DSPD, or ISWR (Option). Additionally, actigraphy is useful as an outcome measure in evaluating the response to treatment for CRSDs (Guideline). A range of therapeutic interventions were considered including planned sleep schedules, timed light exposure, timed melatonin doses, hypnotics, stimulants, and alerting agents. Planned or prescribed sleep schedules are indicated in SWD (Standard) and in JLD, DSPD, ASPD, ISWR (excluding elderly-demented/nursing home residents), and FRD (Option). Specifically dosed and timed light exposure is indicated for each of the circadian disorders with variable success (Option). Timed melatonin administration is indicated for JLD (Standard); SWD, DSPD, and FRD in unsighted persons (Guideline); and for ASPD, FRD in sighted individuals, and for ISWR in children with moderate to severe psychomotor retardation (Option). Hypnotic medications may be indicated to promote or improve daytime sleep among night shift workers (Guideline) and to treat jet lag-induced insomnia (Option). Stimulants may be indicated to improve alertness in JLD and SWD (Option) but may have risks that must be weighed prior to use. Modafinil may be indicated to improve alertness during the night shift for patients with SWD (Guideline). Citation: Morgenthaler TI; Lee-Chiong T; Alessi C; Friedman L; Aurora N; Boehlecke B; Brown T; Chesson AL; Kapur V; Maganti R; Owens J; Pancer J; Swick TJ; Zak R; Standards of Practice Committee of the AASM. Practice Parameters for the Clinical Evaluation and Treatment of Circadian Rhythm Sleep Disorders. SLEEP 2007;30(11):1445-1459. PMID:18041479

  19. PREFACE: XXXth International Colloquium on Group Theoretical Methods in Physics (ICGTMP) (Group30)

    NASA Astrophysics Data System (ADS)

    Brackx, Fred; De Schepper, Hennie; Van der Jeugt, Joris

    2015-04-01

    participants at the Group30 colloquium from 46 different countries. This high number of participants makes the 30th edition of ICGTMP one of the most successful meetings of the series. We were particularly happy with the attendance of 32 students and many young postdocs: this is promising for the future of the research field and of the colloquium series. The attraction of young scientists was promoted by a reduced participation fee, the availability of cheap accommodation in the University Student Guest House, grants from a US-NSF project and grants from the Organising Committee supporting participants from countries with limited financial resources. The colloquium brought together international top researchers, with a variety of different backgrounds but with "group theoretical or algebraic methods" as common ground. The selection of plenary speakers and topics was made by the Organizing Committee, following the suggestions of the International Advisory Committee (consisting of prominent scientists in their domain), and ensuring the diversity of the subjects treated. There were 11 plenary talks, given as well by distinguished world experts as by young rising stars: Matthias Christandl, Alberto De Sole, Rui Loja Fernandes, François Gay-Balmaz, Gitta Kutyniok, Amiram Leviatan, Karl-Hermann Neeb, Christoph Schweigert, Yuji Tachikawa, Luc Vinet and Joshua Zak. Next to the plenary talks, there were 170 talks in six parallel sessions and 10 poster presentations. All scientific activities took place in the Joseph Plateau Building of the Faculty of Engineering and Architecture of Ghent University, a historical building conveniently located in the city centre of Ghent. In this building we could make use of the main lecture hall (400 seats) for the plenary lectures, six lecture rooms for parallel sessions, two offices for organizational activities and registrations, two PC-rooms and a large foyer for coffee breaks, book exhibitions and the poster session. As part of the colloquium, a

  20. Isotope characterisation of historical alabaster quarries in Western Europe.

    NASA Astrophysics Data System (ADS)

    Kloppmann, Wolfram; Leroux, Lise; Bromblet, Philippe; Cooper, Anthony H.; Nestler, Angela; Guerrot, Catherine; Montech, Anne-Thérèse; Worley, Noel

    2015-04-01

    ranging from the 14th to 16th century from the Louvre Museum, Cleveland Museum of Fine Arts, the Petit Palais Museum in Avignon and several regional collections and monuments. Burke W. H., Denison R. E., Hetherington E. A., Koepnick R. B., Nelson H. F., and Otto J. B. (1982) Variation of seawater 87Sr/86Sr throughout Phanerozoic time. Geology 10, 516-519. Claypool G. E., Holser W. T., Kaplan I. R., Sakai H., and Zak I. (1980) The age curves of sulfur and oxygen isotopes in marine sulfate and their mutual interpretation. Chem. Geol. 28, 199-260. Denison R. E., Kirkland D. W., and Evans R. (1998) Using strontium isotopes to determine the age and origin of gypsum and anhydrite beds. J. Geol. 106, 1-17. Kloppmann W., Leroux L., Bromblet P., Guerrot C., Proust E., Cooper A. H., Worley N., Smeds S. A., and Bengtsson H. (2014) Tracing Medieval and Renaissance Alabaster Works of Art Back to Quarries: A Multi-Isotope (Sr, S, O) Approach. Archaeometry 56, 203-219.

  1. Safe Vibrations of Spilling Basin Explosions at "Gotvand Olya Dam" Using Artificial Neural Network

    NASA Astrophysics Data System (ADS)

    Bakhshandeh Amnieh, Hassan; Bahadori, Moein

    2014-12-01

    ów zarejestrowane przy użyciu sejsmografu 3 VIBROLOC. Maksymalna i minimalna odległość pomiędzy środkiem rozkruszanego bloku a stacją rejestrującą ustawiona została na poziomie 244 i 11 m. W celu określenia bezpiecznego poziomu drgań oraz dopuszczalnej wagi ładunku, zastosowano podejście wykorzystujące sieci neuronowe, z wykorzystaniem metody propagacji wstecznej i trzech warstw ukrytych. Błąd średniokwadratowy i współczynnik korelacji sieci wyniosły 1.95 i 0.95, co pozostaje w zgodności z danym uzyskiwanymi z obserwacji empirycznych, wskazując na poprawność i dokładność prognoz. Zakładając wysoki poziom dokładności sieci oraz wysoką dokładność w prognozowaniu poziomu drgań wywołanych przez prace strzałowe, przyjęto że najbliższa odległość od środka rozkruszanego bloku wyniesie 11 m. Uwzględniając standardowe dopuszczalne w przypadku ciężkich budowli betonowych poziomy drgań w wysokości 120 m/s, oszacowano że maksymalna dopuszczalna masa ładunku wyniesie 47.00 Kg, w przeliczeniu na jeden okres zwłoki. Wyniki badań wykorzystane być mogą w planowaniu kolejnych bezpiecznych prac strzałowych.

  2. Exupéry - a mobile fast response system for managing a volcanic crisis

    NASA Astrophysics Data System (ADS)

    Hort, M. K.

    2009-12-01

    analyze the incoming data (e.g. earthquake classification, rapid moment tensor inversion, deformation modeling, an automatic alert level system) which are currently under development. Exupery Working Group: Barsch R (2); Bernsdorf S (3); Beyreuther M (2); Cong X (4); Dahm T (1); Eineder M (4); Erbertseder T (4); Gerstenecker C (5); Hammer C (6); Hansteen T (7); Krieger L (1); Läufer G (5); Maerker C (4); Montalvo Garcia A (1); Ohrnberger M (6); Rix M (4); Rödelsperger S (5); Seidenberger K (4); Shirzaei M (8); Stammler K (9); Stittgen H (9); Valks P (4); Walter T (8); Wallenstein N (10); Wassermann J (2); Zakšek K (1) (1)Institute of Geophysics, Hamburg, Germany; (2) Department of Earth and Environmental Sciences, Geophysical Observatory, Munich, Germany; (3)Centauron - geosoftware & consulting, Weimar, Germany; (4)DLR Oberpfaffenhofen, Germany; (5)Institute of Physical Geodesy, Darmstadt, Germany; (6)Institute of Geosciences, Potsdam, Germany; (7) IFM-GEOMAR, Leibniz Institute of Marine Sciences, Germany; (8)Department physics of the earth, GFZ, Potsdam, Germany; (9)BGR, Geocentre Hannover, Germany; (10)CVARG, Universidade Dos Acores; Portugal

  3. Soil Aeration deficiencies in urban sites

    NASA Astrophysics Data System (ADS)

    Weltecke, Katharina; Gaertig, Thorsten

    2010-05-01

    root density and tree vigour on urban soils. For that purpose gas diffusivity, soil CO2 concentrations and fine root density were measured on typical urban sites in the German cities of Göttingen, Mannheim, and Kassel. The known characteristics of soil aeration on forest sites could be affirmed for urban soils. A negative correlation was found between gas diffusion coefficients and CO2 concentration as well as between fine root extension and CO2 concentration. Changes in crown structure of beech indicating a loss of vigour were found at sites with disturbed aeration. Diffusivity patterns and CO2 concentrations of different specific urban soil sealing types were found. On more natural sites (mulch, grass) increased gas diffusion and low CO2 concentration were present. In contrast, on more compacted or sealed areas (asphalt, paving stone, macadamised road surface) the exchange between soil air and atmosphere was nearly disconnected and soil CO2 concentrations partly exceeded the known critical value of 0.6 % up to tenfold. Literature Burton, A. J.; Pregitzer, K. S.; Zogg, G. P. und Zak D. R. (1997): Effect of measurement CO2 concentrations on sugar maple root respiration. In: Canadian journal of Forest Research, H. 17, S. 421-427. Gaertig, T. (2001): Bodengashaushalt, Feinwurzeln und Vitalität von Eichen. In: Freiburger Bodenkundliche Abhandlungen, H. 40, S. 157. Qi, J.; Marshall, J. D.; Mattson, K. G. (1994): High soil carbon dioxide concentrations inhibit root respiration of Douglas fir. In: New Phytol., Jg. 128, H. 3, S. 435-442. Schack-Kirchner, H.; Gaertig, T.; Wilpert, K. v.; Hildebrand, E. E. (2001): A modified McIntyre and Phillip approach to measure top-soil gas diffusivity in-situ. In: J. Plant Nutr. Soil Sci., Jg. 164, S. 253-258.

  4. Cosmic Lens Reveals Distant Galactic Violence

    NASA Astrophysics Data System (ADS)

    2008-10-01

    By cleverly unraveling the workings of a natural cosmic lens, astronomers have gained a rare glimpse of the violent assembly of a young galaxy in the early Universe. Their new picture suggests that the galaxy has collided with another, feeding a supermassive black hole and triggering a tremendous burst of star formation. Gravitational Lens Diagram Imaging a Distant Galaxy Using a Gravitational Lens CREDIT: Bill Saxton, NRAO/AUI/NSF Click on image for details and more graphics. The astronomers used the National Science Foundation's Very Large Array (VLA) radio telescope to look at a galaxy more than 12 billion light-years from Earth, seen as it was when the Universe was only about 15 percent of its current age. Between this galaxy and Earth lies another distant galaxy, so perfectly aligned along the line of sight that its gravity bends the light and radio waves from the farther object into a circle, or "Einstein Ring." This gravitational lens made it possible for the scientists to learn details of the young, distant galaxy that would have been unobtainable otherwise. "Nature provided us with a magnifying glass to peer into the workings of a nascent galaxy, providing an exciting look at the violent, messy process of building galaxies in the early history of the Universe," said Dominik Riechers, who led this project at the Max Planck Institute for Astronomy in Germany and now is a Hubble Fellow at the California Institute of Technology (Caltech). The new picture of the distant galaxy, dubbed PSS J2322+1944, shows a massive reservoir of gas, 16,000 light-years in diameter, that contains the raw material for building new stars. A supermassive black hole is voraciously eating material, and new stars are being born at the rate of nearly 700 Suns per year. By comparison, our Milky Way Galaxy produces the equivalent of about 3-4 Suns per year. The black hole appears to be near the edge, rather than at the center, of the giant gas reservoir, indicating, the astronomers say

  5. The Application of Modern Techniques and Measurement Devices for Identification of Copper Ore Types and Their Properties / Wykorzystanie nowoczesnych technik i urządzeń pomiarowych do identyfikacji typów rud miedzi i ich właściwości

    NASA Astrophysics Data System (ADS)

    Krawczykowska, Aldona; Trybalski, Kazimierz; Krawczykowski, Damian

    2013-06-01

    The paper concerns the application of modern methods and research techniques for investigations of copper ore properties. It presents the procedure and tools which, when put together, can constitute a source of information on properties of different products of processing and, simultaneously, can be used in the process control and optimization. The copper ore of one of the branches of the KHGM Polska Miedz plc was investigated. The ore samples represented each of the three lithological types occurring in the Polish deposits, i.e. carbonate, shale and sandstone ores. The paper presents the results of microscopic analyses, image analysis of scanning photographs and application procedures of the obtained information for the identification of ore types (application of neuron networks to the recognition of lithological compositions). The present publication will present sample results of modelling of classification identifying two types of ores, i.e. carbonate-shale and sandstone. Summing up the predictions of ore type fractions in respective mixtures for the considered problem of classification it can be stated that the prediction results are good and confirm the lithological predominance of certain ore types in the investigated mixtures. The experimental part comprised the determination of mineralogical and lithological composition of ores (optical microscope) and also elemental composition in the microareas of analysed samples (scanning microscope). Next, the image analysis was performed and subsequently the models classifying the ore types were made. W rudzie miedzi przerabianej w zakładach wzbogacania O/ZWR KGHM Polska Miedź S.A. można wyróżnić trzy typy litologiczne: rudę węglanową, łupkową i piaskowcową. Typy te różnią się właściwościami między innymi takimi jak: rodzaj i zawartość minerałów miedzi, rodzaj minerałów nieużytecznych, zawartość miedzi, twardość i podatność na rozdrabnianie, ale także wielkością i kształtem ziaren

  6. It's Far, It's Small, It's Cool: It's an Icy Exoplanet!

    NASA Astrophysics Data System (ADS)

    2006-01-01

    gravitational microlensing" by J.-P. Beaulieu, D. P. Bennett, P. Fouqué, A. Williams, M. Dominik, U. G. Jørgensen, D. Kubas et al.). High resolution images and their captions are available on this page. This press release is also accompanied by Broadcast quality material.

  7. Practice Parameters for the Surgical Modifications of the Upper Airway for Obstructive Sleep Apnea in Adults

    PubMed Central

    Aurora, R. Nisha; Casey, Kenneth R.; Kristo, David; Auerbach, Sanford; Bista, Sabin R.; Chowdhuri, Susmita; Karippot, Anoop; Lamm, Carin; Ramar, Kannan; Zak, Rochelle; Morgenthaler, Timothy I.

    2010-01-01

    upper airway. Systematic and methodical investigations are needed to improve the quality of evidence, assess additional outcome measures, determine which populations are most likely to benefit from a particular procedure or procedures, and optimize perioperative care. Citation: Aurora RN; Casey KR; Kristo D; Auerbach S; Bista SR; Chowdhuri S; Karippot A; Lamm C; Ramar K; Zak R; Morgenthaler TI. Practice parameters for the surgical modifications of the upper airway for obstructive sleep apnea in adults. SLEEP 2010;33(10):1408-1413. PMID:21061864

  8. Determining Acceptable Explosive Charge Mass Under Different Geological Conditions / Problematyka Wyznaczania Dopuszczalnych Ładunków Mw W Zróżnicowanych Warunkach Geologicznych

    NASA Astrophysics Data System (ADS)

    Pyra, Józef; Sołtys, Anna; Winzer, Jan; Dworzak, Michał; Biessikirski, Andrzej

    2015-09-01

    This article presents a procedure for determining the safety of explosive charges for their surrounding environment, using a limestone mine as a case study. Varied geological structures, as well as other constructions in the surrounding area of a mine, sometimes necessitate the use of two or more ground vibration propagation equations, and thus a variety of explosive charges, depending on the area of rock blasting. This is a crucial issue for the contractor, as it is important to blast the rock as few times as possible, while using the maximum amount of explosive charge for each blast. Wykonywanie robót strzałowych w górnictwie polega na odpalaniu mas materiału wybuchowego (MW) celem uzyskania dużej ilości odpowiednio rozdrobnionego urobku. W momencie zwiększonego popytu na surowce skalne zakłady górnicze zmuszone są do zwielokrotnienia wykonywania prac strzałowych aby zapewnić regularne dostawy produktu. Konsekwencją takich działań jest ponoszenie dodatkowych kosztów operacyjnych. Celem ich minimalizacji oraz uzyskania jak największej efektywności prowadzonych robót strzałowych jest wydłużanie serii, a więc stosowanie coraz to większych mas ładunków materiałów wybuchowych. Efektem takiego postępowanie jest możliwość wystąpienia w otoczeniu oddziaływania o potencjalnie szkodliwym charakterze m. in. drgania parasejsmiczne. Aby wyeliminować powyższy problem oraz zapewnić niezbędny komfort mieszkańcom, Prawo geologiczne i górnicze, Prawo ochrony środowiska i rozporządzenia wykonawcze nakładają na podmiot wykonujący roboty strzałowe obowiązek ochrony otoczenia, poprzez prowadzenie działalności profilaktycznej w zakresie kontroli, monitorowania oraz wyznaczania dopuszczalnych mas ładunków MW. W momencie gdy nie ma możliwości ograniczenia niepożądanych wpływów dynamicznych po przez zmianę parametrów siatki strzałowej czy modyfikację struktury czasowo-częstotliwościowej drgań, jedyną możliwością staje si

  9. Methodology of Calculation the Terminal Settling Velocity Distribution of Spherical Particles for High Values of the Reynold's Number

    NASA Astrophysics Data System (ADS)

    Surowiak, Agnieszka; Brożek, Marian

    2014-03-01

    e jest funkcją dwóch cech prostych, którymi są: wielkość ziarna i gęstość ziarna. Przynależność do określonego podzbioru ziaren jest określona przez wartość dwóch cech, a rozkład tych cech w próbce jest funkcją rozkładów gęstości i wielkości ziarna. Znajomość rozkładu prędkości opadania ziaren w osadzarce jest istotnym parametrem jak znajomość rozkładu wielkości ziarna w procesie przesiewania czy znajomość rozkładu gęstości w procesie wzbogacania w cieczach ciężkich. W artykule przedstawiono metodykę wyliczania rozkładu prędkości opadania ziaren sferycznych w warunkach ruchu turbulentnego wyrażonego przy pomocy równania Newtona. Zarówno gęstość jak i wielkość ziarna są zmiennymi losowymi o określonych rozkładach. W związku z tym prędkość opadania ziarna jako funkcja cech prostych tj. gęstości i wielkości ziarna będzie również zmienną losową o rozkładzie, który jest funkcją rozkładów argumentów prostych. Wykorzystując twierdzenia rachunku prawdopodobieństwa odnoszące się do rozkładów funkcji zmiennych losowych przedstawiono ogólny wzór na funkcję gęstości rozkładu prędkości opadania w warunkach ruchu turbulentnego. Empiryczne rozkłady wielkości i gęstości ziaren aproksymowano rozkładem Weibulla. Rozkład prędkości opadania wyliczono numerycznie i przedstawiono w postaci graficznej. W artykule przedstawiono symulację wyliczania rozkładu prędkości opadania w oparciu o rzeczywiste rozkłady gęstości i średnicy projekcyjnej ziaren zakładając, że ziarna mają kształt sferyczny.

  10. New gravity control in Poland - needs, the concept and the design

    NASA Astrophysics Data System (ADS)

    Krynski, Jan; Olszak, Tomasz; Barlik, Marcin; Dykowski, Przemyslaw

    2013-06-01

    transformation to a new system (as 2nd order network) as well as a definition of gravity system as "zero-tide" system. Seasonal variability of gravity has been discussed indicating that the effects of environmental changes when establishing modern gravity control with absolute gravity survey cannot be totally neglected. Założona w Polsce w ostatniej dekadzie XX wieku zgodnie z obowiązującymi standardami międzynarodowymi Podstawowa Osnowa Grawimetryczna Kraju (POGK), składająca się z około 350 punktów, została oparta na 12 absolutnych punktach grawimetrycznych, na których przyspieszenie siły ciężkości wyznaczono przy użyciu czterech różnych typów grawimetrów absolutnych. Względne pomiary grawimetryczne na punktach tej osnowy, z jednoczesnym dowiązaniem jej do przyspieszenia siły ciężkości na 12 absolutnych punktach grawimetrycznych, wykonały różne grupy pomiarowe przy wykorzystaniu grawimetrów LaCoste&Romberg (LCR). Konstrukcja powstałej sieci grawimetrycznej, w szczególności ograniczona liczba nierównomiernie rozłożonych punktów absolutnych na terenie kraju, na których w dodatku przyspieszenie siły ciężkości wyznaczono różnymi instrumentami w różnych epokach, spowodowały wystąpienie błędów systematycznych w wartościach g na punktach POGK. W niniejszej pracy, przy wykorzystaniu pomiarów grawimetrycznych wykonanych w latach 2007-2008 dokonano oceny tych błędów oraz przeprowadzono dyskusję ich możliwych źródeł. Rozwój technologii absolutnych pomiarów grawimetrycznych, w szczególności instrumentów przeznaczonych do precyzyjnych absolutnych pomiarów grawimetrycznych w warunkach polowych, stwarza możliwość założenia nowego typu osnowy grawimetrycznej, składającej się ze stacji, na których przyspieszenie siły ciężkości jest pomierzone grawimetrami absolutnymi. Nowa osnowa grawimetryczna Polski, która będzie zakładana w latach 2012-2014, będzie się składała z 28 punktów fundamentalnych (mierzonych

  11. Waterproof Anti-Explosive Powders for Coal Mines

    NASA Astrophysics Data System (ADS)

    Buczek, Bronisław; Vogt, Elżbieta

    2014-03-01

    properties not only as a water resistant material but also from the cohesion point of view. On the base of TG, DTG or DTA and EGA curves for all investigated materials was stated that the character of the thermal decomposition of modified samples is the same as this one for raw powder, what is profitable for application of hydrophobized powders as an anti-explosive agent. W górnictwie węgla kamiennego używany jest hydrofobowy pył wapienny jako substancja stosowana w systemie zabezpieczeń przeciwwybuchowych (Cybulski, 2004). Niestety, dotychczasowy sposób wy- twarzania takiego produktu polegający na współmieleniu kamienia wapiennego z kwasem stearynowym staje się praktycznie niemożliwy do stosowania w nowoczesnych zakładach np. kamieniołomy. Sytuacja taka jest wynikiem wprowadzania zmian technologicznych, głównie związanych z wymianą starych konstrukcji młynów na nowe urządzenia. Tym samym istnieje potrzeba poszukiwania nowych metod hydrofobizacji powierzchni pyłów wapiennych. W pracy omówiono dwie nowe metody hydrofobizacji pyłu wapiennego: za pomocą par kwasu stearynowego oraz roztworu silikonowego - Sarsil® H-15. Podczas badań używano surowego pyłu wapiennego pochodzącego z Kopalni Kamienia Wapiennego w Czatkowicach. Materiał ten jest dobrym materiałem do badań gdyż istnieje możliwość porównywania właściwości materiałów hydrofobowych otrzymanych w pracy z właściwościami handlowego pyłu przeciwwybuchowego (Polska Norma, 1994), używanego w polskich kopalniach. Pierwszy sposób hydrofobizacji pyłu wapiennego, polegający na swobodnym opadaniu pyłu wapiennego w oparach kwasu stearynowego przepływających w przeciwprądzie, przeprowadzono w aparacie własnej konstrukcji (Vogt, 2008, 2011). Aparat gwarantuje dobry kontakt modyfikatora z ziarnami pyłu. Pył opadając, nie napotyka żadnych przeszkód ulegał rozproszeniu, a wprowadzony w stanie parowym kwas stearynowy może swobodnie osiadać na jego powierzchni zewn

  12. Determination of Critical Conditions of Spontaneous Combustion of Coal in Longwall Gob Areas / Wyznaczanie Warunków Krytycznych Samozapalania Węgla W Zrobach Ścian

    NASA Astrophysics Data System (ADS)

    Cygankiewicz, Janusz

    2015-09-01

    pożaru niektórych warunków panujących w danym miejscu kopalni, takich jak: - skłonność węgla do samozapalania - zawartość tlenu w powietrzu dopływającym do zagrzewającego się węgla. W pracy przedstawiono numeryczną metodę wyznaczania warunków krytycznych samozapalania węgla w zrobach ścian, czyli takich po spełnieniu których może dojść do samozapalenia. Przyjęto, że znajdujący się w zrobach rozkruszony węgiel ma kształt płaskiej warstwy, sąsiadującej od stropu i spągu ze skałami. Rozważania ograniczono do węgli charakteryzujących się niską zawartością wilgoci. Przyjęto prosty model kinetyki utleniania na powierzchni węgla wyrażony równaniem Arrheniusa. Model ten zakłada niezależność szybkości utleniania od ilości tlenu pochłoniętego przez węgiel. Szybkość reakcji zależy jedynie od temperatury , przy czym występujące w równaniu parametry zmieniają się po osiągnięciu przez węgiel temperatury krytycznej. W artykule przedstawiono matematyczny model samozagrzewania warstwy węgla w zrobach opisujący bilans ciepła w węglu oraz bilans tlenu i bilans ciepła w przepływających gazach. Tworzące model układy równań różniczkowych cząstkowych rozwiązywane są metodami numerycznymi. Opracowany program komputerowy umożliwia wykonywanie stosownych obliczeń. W pracy, na przykładzie węgla z pokładu 405 , przedstawiono sposób wyznaczania warunków krytycznych warstwy rozkruszonego węgla: grubości warstwy, zawartości tlenu w przepływających przez warstwę gazach oraz przewodności cieplnej otaczających skał.

  13. Geotechnical Aspects of Revitalisation of Post-Mining Areas - An Example of the Adaptation of Katowice Hard Coal Mine for the New Silesian Museum / Geotechniczne aspekty rewitalizacji terenów pogórniczych - przykład adaptacji KWK "KATOWICE" na nowe muzeum śląskie

    NASA Astrophysics Data System (ADS)

    Cała, Marek; Ostręga, Anna

    2013-06-01

    The article presents the history of the Katowice Hard Coal Mine and the concept of revitalisation taking into consideration the historical development of the mine which today is closed. The concept accepted for realisation assumes adaptation of the post-mining area with its historical infrastructure for cultural functions, and namely for the construction of the New Silesian Museum. Basing the concept on the idea of minimum interference into the existing spatial layout of the former mine has had the result that the museum areas and garages have been designed under the surface of the area adjacent to the historic facilities of the mine. In relation therewith, it was necessary to carry out the works aimed at reinforcing foundations of the historic buildings and protecting the geotechnical pit slopes. The article presents the technological solutions applied to protect the historic buildings, the lift tower, and the excavations for new facilities of the Silesian Museum. Attention was drawn to the instability of the subsoil and of the rock mass due to previous mining operations conducted in the area, the need to adapt the protection technology to the existing conditions as well as the need of constant monitoring of geotechnical works underway.> It is emphasised that the presented investment is part of an ongoing process aimed at preserving the industrial part of the material cultural heritage of Upper Silesia, for centuries connected with hard coal mining and as such it stands a chance to become a showcase not only for Katowice but for the entire region of Silesia. W artykule przedstawiono historię Kopalni Węgla Kamiennego "Katowice" oraz koncepcję rewitalizacji uwzględniającą historyczną zabudowę nieczynnej już dziś kopalni. Przyjęta do realizacji koncepcja zakłada przystosowanie pogórniczego terenu wraz z zabytkową infrastrukturą dla funkcji kulturowych, a mianowicie budowy Nowego Muzeum Śląskiego. Siedziba Nowego Muzeum Śląskiego lokalizowana jest w

  14. VLT Spectra "Resolve" a Stellar Disk at 25,000 Light-Years Distance

    NASA Astrophysics Data System (ADS)

    2001-04-01

    " ) that appeared in the April 1, 2001 issue of the "Astrophysical Journal" (available on the web at ApJL 550, L173 or astro-ph0011380). Notes [1] Note the recent ESO Press Release 06/01 about the VLT Interferometer. Observations of binary stars that undergo eclipses from time to time also allow indirect studies of the surfaces of the two components; such objects, however, influence each other and cannot be characterized as "normal" stars. [2] The team (the PLANET collaboration) consists of Michael Albrow , Kailash C. Sahu (Space Telescope Science Institute, Baltimore, MD, USA) Jin H. An (Dept. of Astronomy, Ohio State University, Columbus, OH, USA), Jean-Philippe Beaulieu (Institut d'Astrophysique de Paris, France), John A. R. Caldwell , John W. Menzies , Pierre Vermaak (South African Astronomical Observatory, Cape Town, South Africa), Martin Dominik , Penny D. Sackett (Kapteyn Astronomical Institute, Groningen, The Netherlands) , John Greenhill , Kym Hill , Stephen Kane , Robert Watson (University of Tasmania, Hobart, Tasmania, Australia), Ralph Martin , Andrew Williams (Perth Observatory, Australia), Karen Pollard (Physics Dept., Gettysburg College, PA, USA) and Peter H. Hauschildt (Dept. of Physics and Astronomy & Center for Simulational Physics, University of Georgia, Athens, GA, USA). [3] The distance to the Sun is 149.6 million kilometres; 25,000 light-years = 240,000,000,000,000,000 kilometres. 1 billion = 1000 million. [4] The diameter of the cool giant star is approx. 15 million km (about ten times that of the Sun). At the indicated distance, 25,000 light-years, this corresponds to a very small angle, about 10 micro-arcsec. This is equal to the angle subtended by a human hair (diameter 50 microns = 0.05 mm) at a distance of 1000 km. Technical information about the photos PR Photo 16b/01 shows a 0.25-sec acquisition exposure of EROS-BLG-2000-5 , obtained with VLT ANTU + FORS1 in order to set up the spectrograph slit for the subsequent spectral exposures. The