732 research outputs found

    Inferring Deleterious-Mutation Parameters in Natural Daphnia Populations

    Get PDF
    Deng and Lynch (1, 2) proposed to characterize deleterious genomic mutations from changes in the mean and genetic variance of fitness traits upon selfing in outcrossing populations. Such observations can be readily acquired in cyclical parthenogens. Selfing and life-table experiments were performed for two such Daphnia populations. A significant inbreeding depression and an increase of genetic variance for all traits analyzed were observed. Deng and Lynch's (2) procedures were employed to estimate the genomic mutation rate (U), mean dominance coefficient ( [Image: see text] ), mean selection coefficient ( [Image: see text] ), and scaled genomic mutational variance ( [Image: see text] ). On average, [Image: see text] , [Image: see text] , [Image: see text] and [Image: see text] (^ indicates an estimate) are 0.84, 0.30, 0.14 and 4.6E-4 respectively. For the true values, the [Image: see text] and [Image: see text] are lower bounds, and [Image: see text] and [Image: see text] upper bounds

    Mass Parameterizations and Predictions of Isotopic Observables

    Full text link
    We discuss the accuracy of mass models for extrapolating to very asymmetric nuclei and the impact of such extrapolations on the predictions of isotopic observables in multifragmentation. We obtain improved mass predictions by incorporating measured masses and extrapolating to unmeasured masses with a mass formula that includes surface symmetry and Coulomb terms. We find that using accurate masses has a significant impact on the predicted isotopic observables.Comment: 12 pages, 4 figure

    The Liquid-Gas Phase Transitions in a Multicomponent Nuclear System with Coulomb and Surface Effects

    Get PDF
    The liquid-gas phase transition is studied in a multi-component nuclear system using a local Skyrme interaction with Coulomb and surface effects. Some features are qualitatively the same as the results of Muller and Serot which uses relativistic mean field without Coulomb and surface effects. Surface tension brings the coexistance binodal surface to lower pressure. The Coulomb interaction makes the binodal surface smaller and cause another pair of binodal points at low pressure and large proton fraction with less protons in liquid phase and more protons in gas phase.Comment: 20 pages including 7 postscript figure

    Universal coding for classical-quantum channel

    Get PDF
    We construct a universal code for stationary and memoryless classical-quantum channel as a quantum version of the universal coding by Csisz\'{a}r and K\"{o}rner. Our code is constructed by the combination of irreducible representation, the decoder introduced through quantum information spectrum, and the packing lemma

    Fragment Isospin as a Probe of Heavy-Ion Collisions

    Full text link
    Isotope ratios of fragments produced at mid-rapidity in peripheral and central collisions of 114Cd ions with 92Mo and 98Mo target nuclei at E/A = 50 MeV are compared. Neutron-rich isotopes are preferentially produced in central collisions as compared to peripheral collisions. The influence of the size (A), density, N/Z, E*/A, and Eflow/A of the emitting source on the measured isotope ratios was explored by comparison with a statistical model (SMM). The mid-rapidity region associated with peripheral collisions does not appear to be neutron-enriched relative to central collisions.Comment: 12 pages including figure

    Sampling the canonical phase from phase-space functions

    Get PDF
    We discuss the possibility of sampling exponential moments of the canonical phase from the s-parametrized phase space functions. We show that the sampling kernels exist and are well-behaved for any s>-1, whereas for s=-1 the kernels diverge in the origin. In spite of that we show that the phase space moments can be sampled with any predefined accuracy from the Q-function measured in the double-homodyne scheme with perfect detectors. We discuss the effect of imperfect detection and address sampling schemes using other measurable phase-space functions. Finally, we discuss the problem of sampling the canonical phase distribution itself.Comment: 10 pages, 7 figures, REVTe

    Isospin Effects in Nuclear Multifragmentation

    Full text link
    We develop an improved Statistical Multifragmentation Model that provides the capability to calculate calorimetric and isotopic observables with precision. With this new model we examine the influence of nuclear isospin on the fragment elemental and isotopic distributions. We show that the proposed improvements on the model are essential for studying isospin effects in nuclear multifragmentation. In particular, these calculations show that accurate comparisons to experimental data require that the nuclear masses, free energies and secondary decay must be handled with higher precision than many current models accord.Comment: 46 pages, 16 figure

    Out of sight, out of mind: long-term outcomes for people discharged home, to inpatient rehabilitation and to residential aged care after stroke

    Get PDF
    OnlinePubl.Purpose: The aim of this study was to describe differences in long-term outcomes for patients discharged to inpatient rehabilitation facilities (IRFs) following stroke compared to patients discharged directly home or to residential aged care facilities (RACFs). Materials and Methods: Cohort study. Data from the Australian Stroke Clinical Registry were linked to hospital admissions records and the national death index. Main outcomes: death and hospital readmissions up to 12 months post-admission, Health-related Quality of Life (HRQoL) 90-180 days post-admission. Results: Of 8,555 included patients (median age 75, 55% male, 83% ischemic stroke), 4,405 (51.5%) were discharged home, 3,442 (40.2%) to IRFs, and 708 (8.3%) to RACFs. No between-group differences were observed in hazard of death between patients discharged to IRFs versus home. Fewer patients discharged to IRFs were readmitted to hospital within 90, 180 or 365-days compared to patients discharged home (adjusted subhazard ratio [aSHR]:90-days 0.54, 95%CI 0.49, 0.61; aSHR:180-days 0.74, 95%CI 0.67, 0.82; aSHR:365-days 0.85, 95%CI 0.78, 0.93). Fewer patients discharged to IRFs reported problems with mobility compared to those discharged home (adjusted OR 0.54, 95%CI 0.47, 0.63), or to RACFs (aOR 0.35, 95%CI 0.25, 0.48). Overall HRQoL between 90-180 days was worse for people discharged to IRFs versus those discharged home and better than those discharged to RACFs. Conclusions: Several long-term outcomes differed significantly for patients discharged to different settings after stroke. Patients discharged to IRFs reported some better outcomes than people discharge directly home despite having markers of more severe stroke. Implications for rehabilitation: People with mild strokes are usually discharged directly home, people with moderate severity strokes to inpatient rehabilitation, and people with very severe strokes are usually discharged to residential aged care facilities. People discharged to inpatient rehabilitation reported fewer problems with mobility and had a reduced risk of hospital readmission in the first year post-stroke compared to people discharged directly home after stroke. The median self-reported health-related quality of life for people discharged to residential aged care equated to 'worst health state imaginable'.Elizabeth A. Lynch, Angela S. Labberton, Joosup Kim, Monique F. Kilkenny, Nadine E. Andrew, Natasha A. Lannin, Rohan Grimley, Steven G. Faux and Dominique A. Cadilhac; on behalf of the Stroke123 Investigators and AuSCR Consortiu

    Statistical Multifragmentation in Central Au+Au Collisions at 35 MeV/u

    Full text link
    Multifragment disintegrations, measured for central Au + Au collisions at E/A = 35 MeV, are analyzed with the Statistical Multifragmentation Model. Charge distributions, mean fragment energies, and two-fragment correlation functions are well reproduced by the statistical breakup of a large, diluted and thermalized system slightly above the multifragmentation threshold.Comment: Latex file, 8 pages + 4 postscript figures available upon request from [email protected]

    Fragment Production in Non-central Collisions of Intermediate Energy Heavy Ions

    Full text link
    The defining characteristics of fragment emission resulting from the non-central collision of 114Cd ions with 92Mo target nuclei at E/A = 50 MeV are presented. Charge correlations and average relative velocities for mid-velocity fragment emission exhibit significant differences when compared to standard statistical decay. These differences associated with similar velocity dissipation are indicative of the influence of the entrance channel dynamics on the fragment production process
    • …
    corecore