994 research outputs found

    The Urban Unbanked In Mexico And The United States

    Get PDF
    This paper examines the ways in which lower-income households obtain basic financial services in urban communities in Mexico and the United States. And it discusses the efforts that private sector and government organizations are making to lower the cost or improve the quality of those services. The paper summarizes available information on these issues and assesses the rationale and challenges facing the strategies that both countries are using to improve the financial services available to lower-income households, giving particular attention to unbanked households, meaning households that do not have deposit accounts with any regulated deposit-taking institution, and also to lower-income households in large urban areas. In comparing the experiences of the two countries, the paper reviews the extent to which lower-income households are unbanked, their use of non-bank financial services, and strategies for improving financial services to the unbanked. The underlying differences between the countries\u27 typical household incomes-national income per capita in Mexico in 2002 was US8,540,comparedwith8,540, compared with 35,060 in the United States (World Bank 2003)-may also influence the difference in percentage of unbanked-9.1 percent of families in the United States compared with 76.4 percent found in a recent study in Mexico City

    Scanning detection of mutations in human ornithine transcarbamoylase by chemical mismatch cleavage.

    Full text link

    Peptide Chain Termination with Mammalian Release Factor

    Full text link

    Cloning and expression of a mammalian peptide chain release factor with sequence similarity to tryptophanyl-tRNA synthetases

    Get PDF
    The termination of protein synthesis is encoded by in-frame nonsense (stop) codons. Most organisms use three nonsense codons: UGA, UAG, and UAA. In contrast to sense codons, which are decoded by specific tRNAs, nonsense codons are decoded by proteins called release factors (RFs). Here we report the cloning of a mammalian RF cDNA by the use of monoclonal antibodies specific for rabbit RF. Functional studies showed that, when expressed in Escherichia coli, the protein encoded by this cDNA has in vitro biochemical characteristics similar to those of previously characterized mammalian RFs. DNA sequencing of this eukaryotic RF cDNA revealed a remarkable sequence similarity to bacterial and mitochondrial tryptophanyl-tRNA synthetases, with the greatest similarity confined to the synthetase active site, and no obvious similarity to bacterial RFs

    Laying the groundwork at the AGS: Recent results from experiment E895

    Full text link
    The E895 Collaboration at the Brookhaven AGS has performed a systematic investigation of Au+Au collisions at 2-8 AGeV, using a large-acceptance Time Projection Chamber. In addition to extensive measurements of particle flow, spectra, two-particle interferometry, and strangeness production, we have performed novel hybrid analyses, including azimuthally-sensitive pion HBT, extraction of the six-dimensional pion phasespace density, and a first measurement of the Lambda-proton correlation function.Comment: Presented at Quark Matter 2001, 8 pages, 5 figure

    Longitudinal Flow of Protons from 2-8 AGeV Central Au+Au Collisions

    Full text link
    Rapidity distributions of protons from central 197^{197}Au + 197^{197}Au collisions measured by the E895 Collaboration in the energy range from 2 to 8 AGeV at the Brookhaven AGS are presented. Longitudinal flow parameters derived using a thermal model including collective longitudinal expansion are extracted from these distributions. The results show an approximately linear increase in the longitudinal flow velocity, L_{L}, as a function of the logarithm of beam energy.Comment: 5 Pages, including 3 figures, 1 tabl

    Charged Pion Production in 2 to 8 AGeV Central Au+Au Collisions

    Full text link
    Momentum spectra of charged pions over nearly full rapidity coverage from target to beam rapidity have been measured in the 0-5% most central Au+Au collisions in the beam energy range from 2 to 8 AGeV by the E895 Experiment. Using a thermal parameterization to fit the transverse mass spectra, rapidity density distributions are extracted. The observed spectra are compared with predictions from the RQMD v2.3 cascade model and also to a thermal model including longitudinal flow. The total 4Ï€\pi yields of the charged pions are used to infer an initial state entropy produced in the collisions.Comment: 13 pgs, 19 figs, accepted by Phys. Rev. C. Data tables available at http://nuclear.ucdavis.edu/~e895/published_spectra.htm

    Near-threshold production of the multi-strange Ξ−\Xi^- hyperon

    Get PDF
    The yield for the multi-strange Ξ−\Xi^{-} hyperon has been measured in 6 AGeV Au+Au collisions via reconstruction of its decay products π−\pi^{-} and Λ\Lambda, the latter also being reconstructed from its daughter tracks of π−\pi^{-} and p. The measurement is rather close to the threshold for Ξ−\Xi^{-} production and therefore provides an important test of model predictions. The measured yield for Ξ−\Xi^{-} and Λ\Lambda are compared for several centralities. In central collisions the Ξ−\Xi^{-} yield is found to be in excellent agreement with statistical and transport model predictions, suggesting that multi-strange hadron production approaches chemical equilibrium in high baryon density nuclear matter.Comment: Submitted to PR

    Three-layer model with absorption for conservative estimation of the maximum acoustic transmission coefficient through the human skull for transcranial ultrasound stimulation.

    Get PDF
    Transcranial ultrasound stimulation (TUS) has been shown to be a safe and effective technique for non-invasive superficial and deep brain stimulation. Safe and efficient translation to humans requires estimating the acoustic attenuation of the human skull. Nevertheless, there are no international guidelines for estimating the impact of the skull bone. A tissue independent, arbitrary derating was developed by the U.S. Food and Drug Administration to take into account tissue absorption (0.3 dB/cm-MHz) for diagnostic ultrasound. However, for the case of transcranial ultrasound imaging, the FDA model does not take into account the insertion loss induced by the skull bone, nor the absorption by brain tissue. Therefore, the estimated absorption is overly conservative which could potentially limit TUS applications if the same guidelines were to be adopted. Here we propose a three-layer model including bone absorption to calculate the maximum pressure transmission through the human skull for frequencies ranging between 100 kHz and 1.5 MHz. The calculated pressure transmission decreases with the frequency and the thickness of the bone, with peaks for each thickness corresponding to a multiple of half the wavelength. The 95th percentile maximum transmission was calculated over the accessible surface of 20 human skulls for 12 typical diameters of the ultrasound beam on the skull surface, and varies between 40% and 78%. To facilitate the safe adjustment of the acoustic pressure for short ultrasound pulses, such as transcranial imaging or transcranial ultrasound stimulation, a table summarizes the maximum pressure transmission for each ultrasound beam diameter and each frequency

    Model-independent source imaging using two-pion correlations in 2 to 8A GeV Au + Au collisions

    Full text link
    We report a particle source imaging analysis based on two-pion correlations in high multiplicity Au + Au collisions at beam energies between 2 and 8A GeV. We apply the imaging technique introduced by Brown and Danielewicz, which allows a model-independent extraction of source functions with useful accuracy out to relative pion separations of about 20 fm. The extracted source functions have Gaussian shapes. Values of source functions at zero separation are almost constant across the energy range under study. Imaging results are found to be consistent with conventional source parameters obtained from a multidimensional HBT analysis.Comment: 4 pages, 3 figure
    • …
    corecore