213 research outputs found

    Gravitational Lensing Bound On The Average Redshift Of Gamma Ray Bursts In Models With Evolving Lenses

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    Identification of gravitationally lensed Gamma Ray Bursts (GRBs) in the BATSE 4B catalog can be used to constrain the average redshift of the GRBs. In this paper we investigate the effect of evolving lenses on the of GRBs in different cosmological models of universe. The cosmological parameters $\Omega$ and $\Lambda$ have an effect on the of GRBs. The other factor which can change the istheevolutionofgalaxies.Weconsiderthreeevolutionarymodelofgalaxies.Inparticular,wefindthattheupperlimiton is the evolution of galaxies. We consider three evolutionary model of galaxies. In particular, we find that the upper limit on of GRBs is higher in evolving model of galaxies as compared to non-evolving models of galaxies.Comment: 23 pages,one plain LaTeX file with three postscript figures This is modified version with recent BATSE efficiency parameter and with the latest F paramete

    Understanding the use of Virtual Reality in Marketing: a text mining-based review

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    The current study intends to highlight the most relevant studies in simulated realities with special attention to VR and marketing, showing how studies have evolved over time and discussing the findings. A text-mining approach using a Bayesian statistical topic model called latent Dirichlet allocation is employed to conduct a comprehensive analysis of 150 articles from 115 journals, all indexed in Web of Science. The findings reveal seven relevant topics, as well as the number of articles published over time, the authors most cited in VR papers and the leading journals in each topic. The article also provides theoretical and practical implications and suggestions for further research.info:eu-repo/semantics/acceptedVersio

    Gravitational lensing constraint on the cosmic equation of state

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    Recent redshift-distance measurements of Type Ia supernovae (SNe Ia) at cosmological distances suggest that two-third of the energy density of the universe is dominated by dark energy component with an effective negative pressure. This dark energy component is described by the equation of state px=wρxp_{x} = w \rho_{x} (w1)(w \geq -1). We use gravitational lensing statistics to constrain the equation of state of this dark energy. We use n(Δθ)n(\Delta\theta), image separation distribution function of lensed quasars, as a tool to probe ww. We find that for the observed range of Ωm0.20.4\Omega_m \sim 0.2 - 0.4, ww should lie between 0.8w0.4-0.8 \leq w \leq -0.4 in order to have five lensed quasars in a sample of 867 optical quasars. This limit is highly sensitive to lens and Schechter parameters and evolution of galaxies.Comment: Modified results and inclusion of calculations with new set of parameter

    Ribonucleoprotein Purification and Characterization Using RNA Mango

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    The characterization of RNA–protein complexes (RNPs) is a difficult but increasingly important problem in modern biology. By combining the compact RNA Mango aptamer with a fluorogenic thiazole orange desthiobiotin (TO1-Dtb or TO3-Dtb) ligand, we have created an RNA tagging system that simplifies the purification and subsequent characterization of endogenous RNPs. Mango-tagged RNP complexes can be immobilized on a streptavidin solid support and recovered in their native state by the addition of free biotin. Furthermore, Mango-based RNP purification can be adapted to different scales of RNP isolation ranging from pull-down assays to the isolation of large amounts of biochemically defined cellular RNPs. We have incorporated the Mango aptamer into the S. cerevisiae U1 small nuclear RNA (snRNA), shown that the Mango-snRNA is functional in cells, and used the aptamer to pull down a U1 snRNA-associated protein. To demonstrate large-scale isolation of RNPs, we purified and characterized bacterial RNA polymerase holoenzyme (HE) in complex with a Mango-containing 6S RNA. We were able to use the combination of a red-shifted TO3-Dtb ligand and eGFP-tagged HE to follow the binding and release of the 6S RNA by two-color native gel analysis as well as by single-molecule fluorescence cross-correlation spectroscopy. Together these experiments demonstrate how the Mango aptamer in conjunction with simple derivatives of its flurophore ligands enables the purification and characterization of endogenous cellular RNPs in vitro

    Peripheral blood marker of residual acute leukemia after hematopoietic cell transplantation using multi-plex digital droplet PCR

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    BACKGROUND Relapse remains the primary cause of death after hematopoietic cell transplantation (HCT) for acute leukemia. The ability to identify minimal/measurable residual disease (MRD) via the blood could identify patients earlier when immunologic interventions may be more successful. We evaluated a new test that could quantify blood tumor mRNA as leukemia MRD surveillance using droplet digital PCR (ddPCR). METHODS The multiplex ddPCR assay was developed using tumor cell lines positive for the tumor associated antigens (TAA: WT1, PRAME, BIRC5), with homeostatic ABL1. On IRB-approved protocols, RNA was isolated from mononuclear cells from acute leukemia patients after HCT (n = 31 subjects; n = 91 specimens) and healthy donors (n = 20). ddPCR simultaneously quantitated mRNA expression of WT1, PRAME, BIRC5, and ABL1 and the TAA/ABL1 blood ratio was measured in patients with and without active leukemia after HCT. RESULTS Tumor cell lines confirmed quantitation of TAAs. In patients with active acute leukemia after HCT (MRD+ or relapse; n=19), the blood levels of WT1/ABL1, PRAME/ABL1, and BIRC5/ABL1 exceeded healthy donors (p<0.0001, p=0.0286, and p=0.0064 respectively). Active disease status was associated with TAA positivity (1+ TAA vs 0 TAA) with an odds ratio=10.67, (p=0.0070, 95% confidence interval 1.91 - 59.62). The area under the curve is 0.7544. Changes in ddPCR correlated with disease response captured on standard of care tests, accurately denoting positive or negative disease burden in 15/16 (95%). Of patients with MRD+ or relapsed leukemia after HCT, 84% were positive for at least one TAA/ABL1 in the peripheral blood. In summary, we have developed a new method for blood MRD monitoring of leukemia after HCT and present preliminary data that the TAA/ABL1 ratio may may serve as a novel surrogate biomarker for relapse of acute leukemia after HCT

    Neutral current effects in parity violating nuclear force

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    The measurements of the ΔI= 1 part of the parity violating nuclear force when combined with information on neutral current couplings from neutriro scattering and pion production experiments allow an estimate of the isoscalar admixture in the neutral current if it nas a vector axial-vector structure has been shown

    Geological Field Trips

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    This field trip guide organized in the framework of the Goldschmidt Conference 2013, held in Florence from August 25 to 30, 2013, is here presented. The two-days field trip, shows some of the many geological, naturalistic and cultural features in the Fiorano area (Modena), in which history, geology and passion for Ferrari come together in a perfect marriage. The first excursion day is dedicated to visit the Natural Reserve of Salse di Nirano, where the mud volcanoes, produced by the cold mud, salt water and hydrocarbons - mainly methane- can be observed. The second day is devoted to visit the Ferrari Museum and goes on at the Spezzano Castle, hosting the Ceramics Museum. Clays are, in fact, abundant in the hilly margin, where they form badlands, characteristic narrow crests washed out by running waters. In the Castle there is also a Balsamic Vinegar producing Consortium, it’s a peculiar and typical product of Modena province. The itinerary ends with the tour to Enzo Ferrari’s Birthplace at Modena
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