320 research outputs found

    Emulation of a Complex Instruction Set Computer with a Reduced Instruction Set Computer

    Get PDF
    This paper analyzes some of the difficulties of emulating a Complex Instruction Set Computer (CISC) with a Reduced Instruction Set Computer (RISC). It will be shown that although the speed advantage of a RISC is sacrificed, a CISC can be emulated with the exception of software constructs that support nonstandard hardware interfaces. Some concrete examples will be used to help illustrate the execution- time bottlenecks as well as to discuss possible solutions from an architectural point of view for both Silicon and Gallium Arsenide (GaAs). In addition, it will be shown that the most efficient method of emulation involves debugging compiled High-Level Language (HLL) source code on a CISC, and then recompiling the HLL code with a compiler that is familiar with the target RISC architectur

    Observation of associated near-side and away-side long-range correlations in √sNN=5.02  TeV proton-lead collisions with the ATLAS detector

    Get PDF
    Two-particle correlations in relative azimuthal angle (Δϕ) and pseudorapidity (Δη) are measured in √sNN=5.02  TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1  μb-1 of data as a function of transverse momentum (pT) and the transverse energy (ΣETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Δη|<5) “near-side” (Δϕ∼0) correlation that grows rapidly with increasing ΣETPb. A long-range “away-side” (Δϕ∼π) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ΣETPb, is found to match the near-side correlation in magnitude, shape (in Δη and Δϕ) and ΣETPb dependence. The resultant Δϕ correlation is approximately symmetric about π/2, and is consistent with a dominant cos⁡2Δϕ modulation for all ΣETPb ranges and particle pT

    Defending the genome from the enemy within:mechanisms of retrotransposon suppression in the mouse germline

    Get PDF
    The viability of any species requires that the genome is kept stable as it is transmitted from generation to generation by the germ cells. One of the challenges to transgenerational genome stability is the potential mutagenic activity of transposable genetic elements, particularly retrotransposons. There are many different types of retrotransposon in mammalian genomes, and these target different points in germline development to amplify and integrate into new genomic locations. Germ cells, and their pluripotent developmental precursors, have evolved a variety of genome defence mechanisms that suppress retrotransposon activity and maintain genome stability across the generations. Here, we review recent advances in understanding how retrotransposon activity is suppressed in the mammalian germline, how genes involved in germline genome defence mechanisms are regulated, and the consequences of mutating these genome defence genes for the developing germline

    Social immunity modulates competition between coinfecting pathogens

    Get PDF
    Coinfections with multiple pathogens can result in complex within‐host dynamics affecting virulence and transmission. While multiple infections are intensively studied in solitary hosts, it is so far unresolved how social host interactions interfere with pathogen competition, and if this depends on coinfection diversity. We studied how the collective disease defences of ants – their social immunity – influence pathogen competition in coinfections of same or different fungal pathogen species. Social immunity reduced virulence for all pathogen combinations, but interfered with spore production only in different‐species coinfections. Here, it decreased overall pathogen sporulation success while increasing co‐sporulation on individual cadavers and maintaining a higher pathogen diversity at the community level. Mathematical modelling revealed that host sanitary care alone can modulate competitive outcomes between pathogens, giving advantage to fast‐germinating, thus less grooming‐sensitive ones. Host social interactions can hence modulate infection dynamics in coinfected group members, thereby altering pathogen communities at the host level and population level

    Disease Detection by Ultrasensitive Quantification of Microdosed Synthetic Urinary Biomarkers

    Get PDF
    The delivery of exogenous agents can enable noninvasive disease monitoring, but existing low-dose approaches require complex infrastructure. In this paper, we describe a microdose-scale injectable formulation of nanoparticles that interrogate the activity of thrombin, a key regulator of clotting, and produce urinary reporters of disease state. We establish a customized single molecule detection assay that enables urinary discrimination of thromboembolic disease in mice using doses of the nanoparticulate diagnostic agents that fall under regulatory guidelines for “microdosing.”National Science Foundation (U.S.). Graduate Research FellowshipNational Institutes of Health (U.S.) (Ruth L. Kirschstein National Research Service Award F32CA159496-02)Burroughs Wellcome Fund (Career Award at the Scientific Interface)National Cancer Institute (U.S.) (Koch Institute Support (Core) Grant P30-CA14051)David H. Koch Institute for Integrative Cancer Research at MIT (Frontier Research Program

    Search for charged Higgs bosons through the violation of lepton universality in t¯t events using pp collision data at ps = 7 TeV with the ATLAS experiment

    Get PDF
    In several extensions of the Standard Model, the top quark can decay into a bottom quark and a light charged Higgs boson H+, t → bH+, in addition to the Standard Model decay t → bW. Since W bosons decay to the three lepton generations equally, while H+ may predominantly decay into τν, charged Higgs bosons can be searched for using the violation of lepton universality in top quark decays. The analysis in this paper is based on 4.6 fb−1 of proton-proton collision data at √s = 7 TeV collected by the ATLAS experiment at the Large Hadron Collider. Signatures containing leptons (e or μ) and/or a hadronically decaying τ (τhad) are used. Event yield ratios between e+τhad and e+μ, as well as between μ+τhad and μ+e, final states are measured in the data and compared to predictions from simulations. This ratio-based method reduces the impact of systematic uncertainties in the analysis. No significant deviation from the Standard Model predictions is observed. With the assumption that the branching fraction B(H+ → τν) is 100%, upper limits in the range 3.2%–4.4% can be placed on the branching fraction B(t → bH+) for charged Higgs boson masses mH+ in the range 90–140GeV. After combination with results from a search for charged Higgs bosons in t¯t decays using the τhad+jets final state, upper limits on B(t → bH+) can be set in the range 0.8%–3.4%, for mH+ in the range 90–160GeV

    Experimental and Analytical Research of the Heat Transfer Process in the Package of Perforated Plates

    Get PDF
    The need for compact heat exchangers has led to the development of many types of surfaces that enhance the rate of heat transfer, among them the perforated plate heat exchangers, also known as matrix heat exchangers. The perforated plate heat exchangers consist of a series of perforated plates that are separated by a series of spacers. The present study investigates the heat transfer characteristics of the package of perforated plates. Perforated plates were 2 mm thick, with holes with 2 mm in diameter and porosity of 25.6%. The package of one, two, and three perforated plates was set in the channel of the experimental chamber at which entrance was a thrust fan with the ability to control the flow rate. The fluid flow rates, the temperatures of the fluids at the inlet and outlet of the chamber and the temperature of the air between the plates, were measured at the pre-defined locations in the package and the experimental chamber. Based on the measurements, heat transfer coefficients for the individual plates, as well as for the packages of perforated plates were determined. In further research, an iterative analytical procedure for investigation of the heat transfer process and the overall heat transfer coefficient for the package of perforated plates were developed. Based on these analytical and experimental results, conclusions were drawn about the heat transfer in a package of perforated plates.17th Symposium of the Society-of-Thermal-Engineers-of-Serbia (SIMTERM), Oct 20-23, 2015, Sokobanja, Serbi

    Reproductive biology traits affecting productivity of sour cherry

    Get PDF
    The objective of this work was to evaluate variability in reproductive biology traits and the correlation between them in genotypes of 'Oblacinska' sour cherry (Prunus cerasus). High genetic diversity was found in the 41 evaluated genotypes, and significant differences were observed among them for all studied traits: flowering time, pollen germination, number of fruiting branches, production of flower and fruit, number of flowers per bud, fruit set, and limb yield efficiency. The number of fruiting branches significantly influenced the number of flower and fruit, fruit set, and yield efficiency. In addition to number of fruiting branches, yield efficiency was positively correlated with fruit set and production of flower and fruit. Results from principal component analysis suggested a reduction of the reproductive biology factors affecting yield to four main characters: number and structure of fruiting branches, flowering time, and pollen germination. Knowledge of the reproductive biology of the 'Oblacinska' genotypes can be used to select the appropriate ones to be grown or used as parents in breeding programs. In this sense, genotypes II/2, III/9, III/13, and III/14 have very good flower production and satisfactory pollen germination

    A Detection of Cosmological 21 cm Emission from CHIME in Cross-correlation with eBOSS Measurements of the Lyman-α\alpha Forest

    Full text link
    We report the detection of 21 cm emission at an average redshift zˉ=2.3\bar{z} = 2.3 in the cross-correlation of data from the Canadian Hydrogen Intensity Mapping Experiment (CHIME) with measurements of the Lyman-α\alpha forest from eBOSS. Data collected by CHIME over 88 days in the 400500400-500~MHz frequency band (1.8<z<2.51.8 < z < 2.5) are formed into maps of the sky and high-pass delay filtered to suppress the foreground power, corresponding to removing cosmological scales with k0.13 Mpc1k_\parallel \lesssim 0.13\ \text{Mpc}^{-1} at the average redshift. Line-of-sight spectra to the eBOSS background quasar locations are extracted from the CHIME maps and combined with the Lyman-α\alpha forest flux transmission spectra to estimate the 21 cm-Lyman-α\alpha cross-correlation function. Fitting a simulation-derived template function to this measurement results in a 9σ9\sigma detection significance. The coherent accumulation of the signal through cross-correlation is sufficient to enable a detection despite excess variance from foreground residuals 610\sim6-10 times brighter than the expected thermal noise level in the correlation function. These results are the highest-redshift measurement of \tcm emission to date, and set the stage for future 21 cm intensity mapping analyses at z>1.8z>1.8
    corecore