708 research outputs found

    Software for Planning Scientific Activities on Mars

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    Mixed-Initiative Activity Plan Generator (MAPGEN) is a ground-based computer program for planning and scheduling the scientific activities of instrumented exploratory robotic vehicles, within the limitations of available resources onboard the vehicle. MAPGEN is a combination of two prior software systems: (1) an activity-planning program, APGEN, developed at NASA s Jet Propulsion Laboratory and (2) the Europa planner/scheduler from NASA Ames Research Center. MAPGEN performs all of the following functions: Automatic generation of plans and schedules for scientific and engineering activities; Testing of hypotheses (or what-if analyses of various scenarios); Editing of plans; Computation and analysis of resources; and Enforcement and maintenance of constraints, including resolution of temporal and resource conflicts among planned activities. MAPGEN can be used in either of two modes: one in which the planner/scheduler is turned off and only the basic APGEN functionality is utilized, or one in which both component programs are used to obtain the full planning, scheduling, and constraint-maintenance functionality

    Controlling liver cancer internationally: A qualitative study of clinicians' perceptions of current public policy needs

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    <p>Abstract</p> <p>Background</p> <p>Liver cancer is the fifth most common cancer in men and the seventh for women. Usually because of late diagnosis, the prognosis for liver cancer remains poor, resulting in liver cancer being the third most common cause of death from cancer. While some countries have treatment guidelines, little is known or understood about the strategies needed for liver cancer control internationally.</p> <p>Objective</p> <p>To explore leading liver cancer clinician's perceptions of the current public policy needs to control liver cancer internationally.</p> <p>Methods</p> <p>Key informant interviews were conducted with a range of liver cancer clinicians involved in policy in eleven countries. Interviews were digitally recorded, transcribed verbatim, translated (where necessary), de-identified and analyzed by two researchers using a constant comparative method.</p> <p>Results</p> <p>Twenty in-depth semi-structured interviews were conducted in: Australia, China, France, Germany, Italy, Japan, Spain, South Korea, Taiwan, Turkey and the United States. Nine themes were identified and cluster into three groups: 1) Promoting prevention via early risk assessment, focusing on viral hepatitis and other lifestyle factors; 2) Increasing political, public and medical community awareness; and 3) Improving funding for screening, liver cancer surveillance and treatment.</p> <p>Conclusion</p> <p>This study is an important step towards developing an evidence-based approach to assessing preparedness for implementing comprehensive liver cancer control strategies. Evaluation mechanisms to assess countries' performance on the needs described are needed. Future research will concentrate of understanding how these needs vary across countries and the optimal strategies to improve the diagnosis and prognosis of patients with liver cancer internationally.</p

    Chromosomal-level assembly of the Asian Seabass genome using long sequence reads and multi-layered scaffolding

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    We report here the ~670 Mb genome assembly of the Asian seabass (Lates calcarifer), a tropical marine teleost. We used long-read sequencing augmented by transcriptomics, optical and genetic mapping along with shared synteny from closely related fish species to derive a chromosome-level assembly with a contig N50 size over 1 Mb and scaffold N50 size over 25 Mb that span ~90% of the genome. The population structure of L. calcarifer species complex was analyzed by re-sequencing 61 individuals representing various regions across the species' native range. SNP analyses identified high levels of genetic diversity and confirmed earlier indications of a population stratification comprising three clades with signs of admixture apparent in the South-East Asian population. The quality of the Asian seabass genome assembly far exceeds that of any other fish species, and will serve as a new standard for fish genomics

    Measurement of azimuthal asymmetries in inclusive charged dipion production in e+ee^+e^- annihilations at s\sqrt{s} = 3.65 GeV

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    We present a measurement of the azimuthal asymmetries of two charged pions in the inclusive process e+eππXe^+e^-\rightarrow \pi\pi X based on a data set of 62 pb1\rm{pb}^{-1} at the center-of-mass energy s=3.65\sqrt{s}=3.65 GeV collected with the BESIII detector. These asymmetries can be attributed to the Collins fragmentation function. We observe a nonzero asymmetry, which increases with increasing pion momentum. As our energy scale is close to that of the existing semi-inclusive deep inelastic scattering experimental data, the measured asymmetries are important inputs for the global analysis of extracting the quark transversity distribution inside the nucleon and are valuable to explore the energy evolution of the spin-dependent fragmentation function.Comment: 7 pages, 5 figure

    Study of D+Kπ+e+νeD^{+} \to K^{-} \pi^+ e^+ \nu_e

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    We present an analysis of the decay D+Kπ+e+νeD^{+} \to K^{-} \pi^+ e^+ \nu_e based on data collected by the BESIII experiment at the ψ(3770)\psi(3770) resonance. Using a nearly background-free sample of 18262 events, we measure the branching fraction B(D+Kπ+e+νe)=(3.71±0.03±0.08)%\mathcal{B}(D^{+} \to K^{-} \pi^+ e^+ \nu_e) = (3.71 \pm 0.03 \pm 0.08)\%. For 0.8<mKπ<1.00.8<m_{K\pi}<1.0 GeV/c2c^{2} the partial branching fraction is B(D+Kπ+e+νe)[0.8,1]=(3.33±0.03±0.07)%\mathcal{B}(D^{+} \to K^{-} \pi^+ e^+ \nu_e)_{[0.8,1]} = (3.33 \pm 0.03 \pm 0.07)\%. A partial wave analysis shows that the dominant Kˉ(892)0\bar K^{*}(892)^{0} component is accompanied by an \emph{S}-wave contribution accounting for (6.05±0.22±0.18)%(6.05\pm0.22\pm0.18)\% of the total rate and that other components are negligible. The parameters of the Kˉ(892)0\bar K^{*}(892)^{0} resonance and of the form factors based on the spectroscopic pole dominance predictions are also measured. We also present a measurement of the Kˉ(892)0\bar K^{*}(892)^{0} helicity basis form factors in a model-independent way.Comment: 17 pages, 6 figure

    Study of J/ψJ/\psi and ψ(3686)Σ(1385)0Σˉ(1385)0\psi(3686)\rightarrow\Sigma(1385)^{0}\bar\Sigma(1385)^{0} and Ξ0Ξˉ0\Xi^0\bar\Xi^{0}

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    We study the decays of J/ψJ/\psi and ψ(3686)\psi(3686) to the final states Σ(1385)0Σˉ(1385)0\Sigma(1385)^{0}\bar\Sigma(1385)^{0} and Ξ0Ξˉ0\Xi^0\bar\Xi^{0} based on a single baryon tag method using data samples of (1310.6±7.0)×106(1310.6 \pm 7.0) \times 10^{6} J/ψJ/\psi and (447.9±2.9)×106(447.9 \pm 2.9) \times 10^{6} ψ(3686)\psi(3686) events collected with the BESIII detector at the BEPCII collider. The decays to Σ(1385)0Σˉ(1385)0\Sigma(1385)^{0}\bar\Sigma(1385)^{0} are observed for the first time. The measured branching fractions of J/ψJ/\psi and ψ(3686)Ξ0Ξˉ0\psi(3686)\rightarrow\Xi^0\bar\Xi^{0} are in good agreement with, and much more precise, than the previously published results. The angular parameters for these decays are also measured for the first time. The measured angular decay parameter for J/ψΣ(1385)0Σˉ(1385)0J/\psi\rightarrow\Sigma(1385)^{0}\bar\Sigma(1385)^{0}, α=0.64±0.03±0.10\alpha =-0.64 \pm 0.03 \pm 0.10, is found to be negative, different to the other decay processes in this measurement. In addition, the "12\% rule" and isospin symmetry in the J/ψJ/\psi and ψ(3686)ΞΞˉ\psi(3686)\rightarrow\Xi\bar\Xi and Σ(1385)Σˉ(1385)\Sigma(1385)\bar{\Sigma}(1385) systems are tested.Comment: 11 pages, 7 figures. This version is consistent with paper published in Phys.Lett. B770 (2017) 217-22

    Measurement of the e+eπ+π\mathrm e^+\mathrm e^-\rightarrow\mathrm\pi^+\mathrm\pi^- Cross Section between 600 and 900 MeV Using Initial State Radiation

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    We extract the e+eπ+πe^+e^-\rightarrow \pi^+\pi^- cross section in the energy range between 600 and 900 MeV, exploiting the method of initial state radiation. A data set with an integrated luminosity of 2.93 fb1^{-1} taken at a center-of-mass energy of 3.773 GeV with the BESIII detector at the BEPCII collider is used. The cross section is measured with a systematic uncertainty of 0.9%. We extract the pion form factor Fπ2|F_\pi|^2 as well as the contribution of the measured cross section to the leading order hadronic vacuum polarization contribution to (g2)μ(g-2)_\mu. We find this value to be aμππ,LO(600900  MeV)=(368.2±2.5stat±3.3sys)1010a_\mu^{\pi\pi,\rm LO}(600-900\;\rm MeV) = (368.2 \pm 2.5_{\rm stat} \pm 3.3_{\rm sys})\cdot 10^{-10}.Comment: 14 pages, 7 figures, accepted by PL

    Measurements of absolute hadronic branching fractions of Λc+\Lambda_{c}^{+} baryon

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    Using 567pb1567\rm{pb}^{-1} of e+ee^+e^- collisions recorded at s=4.599GeV\sqrt{s}=4.599\rm{GeV} with the BESIII detector, we report first measurements of absolute hadronic branching fractions of Cabibbo-favored decays of the Λc+\Lambda_{c}^{+} baryon with a double-tag technique. A global least-square fitter is utilized to improve the measured precision. Among the measurements for twelve Λc+\Lambda_{c}^{+} decay modes, the branching fraction for Λc+pKπ+\Lambda_{c}^{+} \rightarrow pK^-\pi^+ is determined to be (5.84±0.27±0.23)%(5.84\pm0.27\pm0.23)\%, where the first uncertainty is statistical and the second is systematic. In addition, the measurements of the branching fractions of the other eleven Cabbibo-favored hadronic decay modes are significantly improved

    Search for C-parity violation in J/ψγγJ/ \psi \to \gamma\gamma and γϕ \gamma \phi

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    Using 1.06×1081.06\times10^8 ψ(3686)\psi(3686) events recorded in e+ee^{+}e^{-} collisions at s=\sqrt{s}= 3.686 GeV with the BESIII at the BEPCII collider, we present searches for C-parity violation in J/ψγγJ/\psi \to \gamma\gamma and γϕ \gamma \phi decays via ψ(3686)J/ψπ+π\psi(3686) \to J/\psi \pi^+\pi^-. No significant signals are observed in either channel. Upper limits on the branching fractions are set to be B(J/ψγγ)<2.7×107\mathcal{B}(J/\psi \to \gamma\gamma) < 2.7 \times 10^{-7} and B(J/ψγϕ)<1.4×106\mathcal{B}(J/\psi \to \gamma\phi) < 1.4 \times 10^{-6} at the 90\% confidence level. The former is one order of magnitude more stringent than the previous upper limit, and the latter represents the first limit on this decay channel.Comment: 7 pages, 2 figure
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