336 research outputs found

    An Initative to Narrow the Digital Divide: Preliminary Results

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    The Digital Divide has been defined as a gap between those with access to new information technologies and those without. The term is also used to characterize the disparity between those who can effectively use information technology and those who cannot. This paper first explores the digital divide within the United States (U.S.) and worldwide. Factors contributing to the widening of the gap are identified, including differences in income, age, education, race, household type, and geographic location. In an effort to reduce the Digital Divide, various initiatives have been undertaken. Preliminary results of an initiative designed to narrow the divide are presented

    A Community Initiative that Diminished the Digital Divide

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    During the 1990s, businesses began relying on the convenience of ubiquitous computer systems and on the efficiencies of digital networks. This new techno-economic dynamic prompted White House administrations of the 1990s to take note of public policy issues surrounding the information superhighway and the digital divide. Yet, because the digital world seems intangible, relatively few policymakers connected the virtual world with its potential impact on the physical world [Frye, 2002]. A case study of a community organizing program was conducted to examine the digital divide in the United States and its connection to other factors. This field study of computer-illiterate people in a public housing community was undertaken to better understand the complexities of the have vs. have not divide so that effective public policies can be deployed to bridge the gap. Community members ran this program with assistance from volunteers and set their own technology learning plan to minimize their techno-disadvantage. Overall, the results indicate the importance of a community-driven organizing strategy. Even though the program was effective in that participants learned computers skills, their emotional state declined. Becoming computer literate did not eliminate feelings of isolation from mainstream society, which is considered a factor contributing to the divide. Those who are adversely digitally divided may also be divided by a culture of failure. Bridging the digital divide requires a more comprehensive approach--and not a quick fix. It requires a process that is, for example, driven by a local community program and strategy to initiate and sustain members\u27 use of technology

    An Integrated Disease/Pharmacokinetic/Pharmacodynamic Model Suggests Improved Interleukin-21 Regimens Validated Prospectively for Mouse Solid Cancers

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    Interleukin (IL)-21 is an attractive antitumor agent with potent immunomodulatory functions. Yet thus far, the cytokine has yielded only partial responses in solid cancer patients, and conditions for beneficial IL-21 immunotherapy remain elusive. The current work aims to identify clinically-relevant IL-21 regimens with enhanced efficacy, based on mathematical modeling of long-term antitumor responses. For this purpose, pharmacokinetic (PK) and pharmacodynamic (PD) data were acquired from a preclinical study applying systemic IL-21 therapy in murine solid cancers. We developed an integrated disease/PK/PD model for the IL-21 anticancer response, and calibrated it using selected “training” data. The accuracy of the model was verified retrospectively under diverse IL-21 treatment settings, by comparing its predictions to independent “validation” data in melanoma and renal cell carcinoma-challenged mice (R2>0.90). Simulations of the verified model surfaced important therapeutic insights: (1) Fractionating the standard daily regimen (50 µg/dose) into a twice daily schedule (25 µg/dose) is advantageous, yielding a significantly lower tumor mass (45% decrease); (2) A low-dose (12 µg/day) regimen exerts a response similar to that obtained under the 50 µg/day treatment, suggestive of an equally efficacious dose with potentially reduced toxicity. Subsequent experiments in melanoma-bearing mice corroborated both of these predictions with high precision (R2>0.89), thus validating the model also prospectively in vivo. Thus, the confirmed PK/PD model rationalizes IL-21 therapy, and pinpoints improved clinically-feasible treatment schedules. Our analysis demonstrates the value of employing mathematical modeling and in silico-guided design of solid tumor immunotherapy in the clinic

    The Pancreatic Expression Database: 2018 update.

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    The Pancreatic Expression Database (PED, http://www.pancreasexpression.org) continues to be a major resource for mining pancreatic -omics data a decade after its initial release. Here, we present recent updates to PED and describe its evolution into a comprehensive resource for extracting, analysing and integrating publicly available multi-omics datasets. A new analytical module has been implemented to run in parallel with the existing literature mining functions. This analytical module has been created using rich data content derived from pancreas-related specimens available through the major data repositories (GEO, ArrayExpress) and international initiatives (TCGA, GENIE, CCLE). Researchers have access to a host of functions to tailor analyses to meet their needs. Results are presented using interactive graphics that allow the molecular data to be visualized in a user-friendly manner. Furthermore, researchers are provided with the means to superimpose layers of molecular information to gain greater insight into alterations and the relationships between them. The literature-mining module has been improved with a redesigned web appearance, restructured query platforms and updated annotations. These updates to PED are in preparation for its integration with the Pancreatic Cancer Research Fund Tissue Bank (PCRFTB), a vital resource of pancreas cancer tissue for researchers to support and promote cutting-edge research.Pancreatic Cancer Research Fund [Tissue Bank grant]; Cancer Research UK [Grant A12008]; Breast Cancer Campaign [Tissue Bank Bioinformatics grant TB2016BIF]

    Transverse-momentum-dependent Multiplicities of Charged Hadrons in Muon-Deuteron Deep Inelastic Scattering

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    A semi-inclusive measurement of charged hadron multiplicities in deep inelastic muon scattering off an isoscalar target was performed using data collected by the COMPASS Collaboration at CERN. The following kinematic domain is covered by the data: photon virtuality Q2>1Q^{2}>1 (GeV/cc)2^2, invariant mass of the hadronic system W>5W > 5 GeV/c2c^2, Bjorken scaling variable in the range 0.003<x<0.40.003 < x < 0.4, fraction of the virtual photon energy carried by the hadron in the range 0.2<z<0.80.2 < z < 0.8, square of the hadron transverse momentum with respect to the virtual photon direction in the range 0.02 (GeV/c)2<PhT2<3c)^2 < P_{\rm{hT}}^{2} < 3 (GeV/cc)2^2. The multiplicities are presented as a function of PhT2P_{\rm{hT}}^{2} in three-dimensional bins of xx, Q2Q^2, zz and compared to previous semi-inclusive measurements. We explore the small-PhT2P_{\rm{hT}}^{2} region, i.e. PhT2<1P_{\rm{hT}}^{2} < 1 (GeV/cc)2^2, where hadron transverse momenta are expected to arise from non-perturbative effects, and also the domain of larger PhT2P_{\rm{hT}}^{2}, where contributions from higher-order perturbative QCD are expected to dominate. The multiplicities are fitted using a single-exponential function at small PhT2P_{\rm{hT}}^{2} to study the dependence of the average transverse momentum PhT2\langle P_{\rm{hT}}^{2}\rangle on xx, Q2Q^2 and zz. The power-law behaviour of the multiplicities at large PhT2P_{\rm{hT}}^{2} is investigated using various functional forms. The fits describe the data reasonably well over the full measured range.Comment: 28 pages, 20 figure

    Longitudinal double spin asymmetries in single hadron quasi-real photoproduction at high pTp_T

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    We measured the longitudinal double spin asymmetries ALLA_{LL} for single hadron muo-production off protons and deuterons at photon virtuality Q2Q^2 < 1(GeV/c\it c)2^2 for transverse hadron momenta pTp_T in the range 0.7 GeV/c\it c to 4 GeV/c\it c . They were determined using COMPASS data taken with a polarised muon beam of 160 GeV/c\it c or 200 GeV/c\it c impinging on polarised 6LiD\mathrm{{}^6LiD} or NH3\mathrm{NH_3} targets. The experimental asymmetries are compared to next-to-leading order pQCD calculations, and are sensitive to the gluon polarisation ΔG\Delta G inside the nucleon in the range of the nucleon momentum fraction carried by gluons 0.05<xg<0.20.05 < x_g < 0.2

    Interplay among transversity induced asymmetries in hadron leptoproduction

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    In the fragmentation of a transversely polarized quark several left-right asymmetries are possible for the hadrons in the jet. When only one unpolarized hadron is selected, it exhibits an azimuthal modulation known as Collins effect. When a pair of oppositely charged hadrons is observed, three asymmetries can be considered, a di-hadron asymmetry and two single hadron asymmetries. In lepton deep inelastic scattering on transversely polarized nucleons all these asymmetries are coupled with the transversity distribution. From the high statistics COMPASS data on oppositely charged hadron-pair production we have investigated for the first time the dependence of these three asymmetries on the difference of the azimuthal angles of the two hadrons. The similarity of transversity induced single and di-hadron asymmetries is discussed. A new analysis of the data allows to establish quantitative relationships among them, providing for the first time strong experimental indication that the underlying fragmentation mechanisms are all driven by a common physical process.Comment: 6 figure

    Interplay among transversity induced asymmetries in hadron leptoproduction

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    In the fragmentation of a transversely polarized quark several left-right asymmetries are possible for the hadrons in the jet. When only one unpolarized hadron is selected, it exhibits an azimuthal modulation known as Collins effect. When a pair of oppositely charged hadrons is observed, three asymmetries can be considered, a di-hadron asymmetry and two single hadron asymmetries. In lepton deep inelastic scattering on transversely polarized nucleons all these asymmetries are coupled with the transversity distribution. From the high statistics COMPASS data on oppositely charged hadron-pair production we have investigated for the first time the dependence of these three asymmetries on the difference of the azimuthal angles of the two hadrons. The similarity of transversity induced single and di-hadron asymmetries is discussed. A new analysis of the data allows to establish quantitative relationships among them, providing for the first time strong experimental indication that the underlying fragmentation mechanisms are all driven by a common physical process.Comment: 6 figure

    Collins and Sivers asymmetries in muonproduction of pions and kaons off transversely polarised proton

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    Measurements of the Collins and Sivers asymmetries for charged pions and charged and neutral kaons produced in semi-inclusive deep-inelastic scattering of high energy muons off transversely polarised protons are presented. The results were obtained using all the available COMPASS proton data, which were taken in the years 2007 and 2010. The Collins asymmetries exhibit in the valence region a non-zero signal for pions and there are hints of non-zero signal also for kaons. The Sivers asymmetries are found to be positive for positive pions and kaons and compatible with zero otherwise.Comment: 15 pages, 13 figures and 1 tabl

    The Spin Structure Function g1pg_1^{\rm p} of the Proton and a Test of the Bjorken Sum Rule

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    New results for the double spin asymmetry A1pA_1^{\rm p} and the proton longitudinal spin structure function g1pg_1^{\rm p} are presented. They were obtained by the COMPASS collaboration using polarised 200 GeV muons scattered off a longitudinally polarised NH3_3 target. The data were collected in 2011 and complement those recorded in 2007 at 160\,GeV, in particular at lower values of xx. They improve the statistical precision of g1p(x)g_1^{\rm p}(x) by about a factor of two in the region x0.02x\lesssim 0.02. A next-to-leading order QCD fit to the g1g_1 world data is performed. It leads to a new determination of the quark spin contribution to the nucleon spin, ΔΣ\Delta \Sigma ranging from 0.26 to 0.36, and to a re-evaluation of the first moment of g1pg_1^{\rm p}. The uncertainty of ΔΣ\Delta \Sigma is mostly due to the large uncertainty in the present determinations of the gluon helicity distribution. A new evaluation of the Bjorken sum rule based on the COMPASS results for the non-singlet structure function g1NS(x,Q2)g_1^{\rm NS}(x,Q^2) yields as ratio of the axial and vector coupling constants gA/gV=1.22±0.05 (stat.)±0.10 (syst.)|g_{\rm A}/g_{\rm V}| = 1.22 \pm 0.05~({\rm stat.}) \pm 0.10~({\rm syst.}), which validates the sum rule to an accuracy of about 9\%.Comment: 19 pages, 8 figures and table
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