9,811 research outputs found
Progress report on the Heavy Ions in Space (HIIS) experiment
One of the objectives of the Heavy Ions In Space (HIIS) experiment is to investigate heavy ions which appear at Long Duration Exposure Facility (LDEF) below the geomagnetic cutoff for fully-ionized galactic cosmic rays. Possible sources of such 'below-cutoff' particles are partially-ionized solar energetic particles, the anomalous component of cosmic rays, and magnetospherically-trapped particles. In recent years, there have also been reports of below-cutoff ions which do not appear to be from any known source. Although most of these observations are based on only a handful of ions, they have led to speculation about 'partially-ionized galactic cosmic rays' and 'near-by cosmic ray sources'. The collecting power of HIIS is order of magnitude larger than that of the instruments which reported these results, so HIIS should be able to confirm these observations and perhaps discover the source of these particles. Preliminary results on below-cutoff heavy-ions are reported. Observations to possible known sources of such ions are compared. A second objective of the HIIS experiment is to measure the elemental composition of ultraheavy galactic cosmic rays, beginning in the tin-barium region of the periodic table. A report on the status of this analysis is presented
Growth, Mortality, Food Habits, and Fecundity of the Buffalo River Smallmouth Bass
Total length-scale radius, and length-weight relationships were determined for smallmouth bass from the Buffalo River. The back calculated lengths were used in analyzing the age-length data by the Bertalanffy growth formula. Asymptotic length and weight were estimated as 58.3 cm and 4.6 lbs, respectively. Annual mortality of 36 percent was estimated by the catch curve method. Insects (54%), fishes (16%), and crayfish (14%) were the abundant food organisms by frequency of occurrence; while fishes (64%) and crayfish (29%) were the dominant food items by the gravimetric method. Based on the gonosomatic indices and frequency distribution of ovum diameter measurements, smallmouth bass spawn during April-June. All ova greater than or equal to 1.1 mm were considered mature and the relationships between total length, weight, and age to fecundity were estimated as: log F =5.05 logL-8.89301 ;F =18.56 W -1680.4; log F =3.84 log A +1.51560, respectively
Toward a descriptive model of galactic cosmic rays in the heliosphere
Researchers review the elements that enter into phenomenological models of the composition, energy spectra, and the spatial and temporal variations of galactic cosmic rays, including the so-called anomalous cosmic ray component. Starting from an existing model, designed to describe the behavior of cosmic rays in the near-Earth environment, researchers suggest possible updates and improvements to this model, and then propose a quantitative approach for extending such a model into other regions of the heliosphere
A Gravitational Theory of the Quantum
The synthesis of quantum and gravitational physics is sought through a
finite, realistic, locally causal theory where gravity plays a vital role not
only during decoherent measurement but also during non-decoherent unitary
evolution. Invariant set theory is built on geometric properties of a compact
fractal-like subset of cosmological state space on which the universe is
assumed to evolve and from which the laws of physics are assumed to derive.
Consistent with the primacy of , a non-Euclidean (and hence non-classical)
state-space metric is defined, related to the -adic metric of number
theory where is a large but finite Pythagorean prime. Uncertain states on
are described using complex Hilbert states, but only if their squared
amplitudes are rational and corresponding complex phase angles are rational
multiples of . Such Hilbert states are necessarily -distant from
states with either irrational squared amplitudes or irrational phase angles.
The gappy fractal nature of accounts for quantum complementarity and is
characterised numerically by a generic number-theoretic incommensurateness
between rational angles and rational cosines of angles. The Bell inequality,
whose violation would be inconsistent with local realism, is shown to be
-distant from all forms of the inequality that are violated in any
finite-precision experiment. The delayed-choice paradox is resolved through the
computational irreducibility of . The Schr\"odinger and Dirac equations
describe evolution on in the singular limit at . By contrast,
an extension of the Einstein field equations on is proposed which reduces
smoothly to general relativity as . Novel proposals for
the dark universe and the elimination of classical space-time singularities are
given and experimental implications outlined
On the Lawrence–Doniach and Anisotropic Ginzburg–Landau Models for Layered Superconductors
The authors consider two models, the Lawrence-Doniach and the anisotropic Ginzburg-Landau models for layered superconductors such as the recently discovered high-temperature superconductors. A mathematical description of both models is given and existence results for their solution are derived. The authors then relate the two models in the sense that they show that as the layer spacing tends to zero, the Lawrence-Doniach model reduces to the anisotropic Ginzburg- Landau model. Finally, simplified versions of the models are derived that can be used to accurately simulate high-temperature superconductors
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Mouse cytomegalovirus-experienced ILC1s acquire a memory response dependent on the viral glycoprotein m12.
Innate lymphoid cells (ILCs) are tissue-resident sentinels that are essential for early host protection from pathogens at initial sites of infection. However, whether pathogen-derived antigens directly modulate the responses of tissue-resident ILCs has remained unclear. In the present study, it was found that liver-resident type 1 ILCs (ILC1s) expanded locally and persisted after the resolution of infection with mouse cytomegalovirus (MCMV). ILC1s acquired stable transcriptional, epigenetic and phenotypic changes a month after the resolution of MCMV infection, and showed an enhanced protective effector response to secondary challenge with MCMV consistent with a memory lymphocyte response. Memory ILC1 responses were dependent on the MCMV-encoded glycoprotein m12, and were independent of bystander activation by proinflammatory cytokines after heterologous infection. Thus, liver ILC1s acquire adaptive features in an MCMV-specific manner
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