3,019 research outputs found
Three-dose versus four-dose primary schedules for tick-borne encephalitis (TBE) vaccine FSME-immun for those aged 50 years or older : A single-centre, open-label, randomized controlled trial
Background: TBE vaccination failures among those past middle age have raised concern about immune response declining with age. We investigated immunogenicity of the TBE-vaccine FSME-Immun among those aged 50+ years using the standard three-dose primary series and alternative four-dose schedules. Methods: In this single-centre, open-label, randomized controlled trial, 200 TBE-naive Swedish adults were given primary TBE vaccination with FSME-Immun. Those aged 50+ years (n = 150) were randomized to receive the standard three-dose (days 0-30-360) or one of two four-dose series (0-7-21-360; 0-30- 90-360). For participants < 50 years (n = 50) the standard three-dose schedule was used. Titres of neu-tralizing antibodies were determined on days 0, 60, 120, 360, and 400. The main outcome was the log titre of TBE virus-specific neutralizing antibodies on day 400. Results: The three-dose schedule yielded lower antibody titres among those aged 50+ years than the younger participants on day 400 (geometric mean titre 41 versus 74, p < 0.05). The older group showed higher titres for the four-dose 0-7-21-360 than the standard three-dose schedule both on day 400 (103 versus 41, p < 0.01; primary end point) and at the other testing points (days 60,120, 360). Using the other four-dose schedule (0-30-90-360), no such difference was observed on day 400 (63 versus 41, NS). Conclusion: Immune response to the TBE vaccine declined with age. A four-dose schedule (0-7-21-360) may benefit those aged 50 years or older. This study is registered at ClinicalTrials.gov, NCT01361776. (c) 2022 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/).Peer reviewe
Age truncation and portfolio effects in Puget Sound Pacific herring
Forage fish undergo dramatic changes in abundance through time. Long-term fluctuations, which have historically been attributed to changes in recruitment, may also be due to changes in adult mortality. Pacific herring, a lightly exploited forage fish in Puget Sound, WA, have exhibited shifts in age structure and decreases in spawning biomass during the past 30 years. Here, we investigate changes in adult mortality as a potential explanation for these shifts. Using a hierarchical, age-structured population model, we indicate that adult natural mortality for Puget Sound Pacific herring has increased since 1973. We find that natural mortality has increased for every age class of adult (age 3+), especially age 4 fish, whose estimated mortality has doubled over the survey time period (from M=0.84 to M=1.76). We demonstrate that long-term shifts in mortality explain changes in age structure, and may explain biomass declines and failure to reach management thresholds for some spawning sites in Puget Sound. Temporal shifts in natural adult mortality could have negative implications for herring and herring predators. For predators, these implications include a reduction in the stability of the herring resource
Understanding initial data for black hole collisions
Numerical relativity, applied to collisions of black holes, starts with
initial data for black holes already in each other's strong field. The initial
hypersurface data typically used for computation is based on mathematical
simplifying prescriptions, such as conformal flatness of the 3-geometry and
longitudinality of the extrinsic curvature. In the case of head on collisions
of equal mass holes, there is evidence that such prescriptions work reasonably
well, but it is not clear why, or whether this success is more generally valid.
Here we study these questions by considering the ``particle limit'' for head on
collisions of nonspinning holes. Einstein's equations are linearized in the
mass of the small hole, and described by a single gauge invariant spacetime
function psi, for each multipole. The resulting equations have been solved by
numerical evolution for collisions starting from various initial separations,
and the evolution is studied on a sequence of hypersurfaces. In particular, we
extract hypersurface data, that is psi and its time derivative, on surfaces of
constant background Schwarzschild time. These evolved data can then be compared
with ``prescribed'' data, evolved data can be replaced by prescribed data on
any hypersurface, and evolved further forward in time, a gauge invariant
measure of deviation from conformal flatness can be evaluated, etc. The main
findings of this study are: (i) For holes of unequal mass the use of prescribed
data on late hypersurfaces is not successful. (ii) The failure is likely due to
the inability of the prescribed data to represent the near field of the smaller
hole. (iii) The discrepancy in the extrinsic curvature is more important than
in the 3-geometry. (iv) The use of the more general conformally flat
longitudinal data does not notably improve this picture.Comment: 20 pages, REVTEX, 26 PS figures include
Feeding Modified Distillers Grains With Solubles and Wet Corn Gluten Feed (Synergy) to Adapt Cattle to Finishing Diets
An experiment with 236 steers and eight pens per treatment (14 or 15 steers/pen) evaluated two grain adaptation treatments. Treatments included adapting steers by decreasing alfalfa (CON) or decreasing a combination of distillers grains and corn gluten feed (SYNERGY) followed by feeding a common finishing diet to slaughter. Performance and carcass traits did not differ between adaptation systems. A combination of MDGS and SYNERGY can be used to adapt beef cattle to feedlot diets with efficacy of the traditional, foragebased method
Inference with interference between units in an fMRI experiment of motor inhibition
An experimental unit is an opportunity to randomly apply or withhold a
treatment. There is interference between units if the application of the
treatment to one unit may also affect other units. In cognitive neuroscience, a
common form of experiment presents a sequence of stimuli or requests for
cognitive activity at random to each experimental subject and measures
biological aspects of brain activity that follow these requests. Each subject
is then many experimental units, and interference between units within an
experimental subject is likely, in part because the stimuli follow one another
quickly and in part because human subjects learn or become experienced or
primed or bored as the experiment proceeds. We use a recent fMRI experiment
concerned with the inhibition of motor activity to illustrate and further
develop recently proposed methodology for inference in the presence of
interference. A simulation evaluates the power of competing procedures.Comment: Published by Journal of the American Statistical Association at
http://www.tandfonline.com/doi/full/10.1080/01621459.2012.655954 . R package
cin (Causal Inference for Neuroscience) implementing the proposed method is
freely available on CRAN at https://CRAN.R-project.org/package=ci
Dissipative fluids out of hydrostatic equilibrium
In the context of the M\"{u}ller-Israel-Stewart second order phenomenological
theory for dissipative fluids, we analyze the effects of thermal conduction and
viscosity in a relativistic fluid, just after its departure from hydrostatic
equilibrium, on a time scale of the order of relaxation times. Stability and
causality conditions are contrasted with conditions for which the ''effective
inertial mass'' vanishes.Comment: 21 pages, 1 postscript figure (LaTex 2.09 and epsfig.sty required)
Submitted to Classical and Quantum Gravit
Head-on collision of unequal mass black holes: close-limit predictions
The close-limit method has given approximations in excellent agreement with
those of numerical relativity for collisions of equal mass black holes. We
consider here colliding holes with unequal mass, for which numerical relativity
results are not available. We try to ask two questions: (i) Can we get
approximate answers to astrophysical questions (ideal mass ratio for energy
production, maximum recoil velocity, etc.), and (ii) can we better understand
the limitations of approximation methods. There is some success in answering
the first type of question, but more with the second, especially in connection
with the issue of measures of the intrinsic mass of the colliding holes, and of
the range of validity of the method.Comment: 19 pages, RevTeX + 9 postscript figure
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