71 research outputs found
Gravitational Couplings of Intrinsic Spin
The gravitational couplings of intrinsic spin are briefly reviewed. A
consequence of the Dirac equation in the exterior gravitational field of a
rotating mass is considered in detail, namely, the difference in the energy of
a spin-1/2 particle polarized vertically up and down near the surface of a
rotating body is . Here is the latitude and
, where and are, respectively, the angular
momentum and radius of the body. It seems that this relativistic quantum
gravitational effect could be measurable in the foreseeable future.Comment: LaTeX file, no figures, 16 page
Improving the clinical assessment of consciousness with advances in electrophysiological and neuroimaging techniques
In clinical neurology, a comprehensive understanding of consciousness has been regarded as an abstract concept - best left to philosophers. However, times are changing and the need to clinically assess consciousness is increasingly becoming a real-world, practical challenge. Current methods for evaluating altered levels of consciousness are highly reliant on either behavioural measures or anatomical imaging. While these methods have some utility, estimates of misdiagnosis are worrisome (as high as 43%) - clearly this is a major clinical problem. The solution must involve objective, physiologically based measures that do not rely on behaviour. This paper reviews recent advances in physiologically based measures that enable better evaluation of consciousness states (coma, vegetative state, minimally conscious state, and locked in syndrome). Based on the evidence to-date, electroencephalographic and neuroimaging based assessments of consciousness provide valuable information for evaluation of residual function, formation of differential diagnoses, and estimation of prognosis
A new species of Stenobiella Tillyard (Neuroptera, Berothidae) from Australia
Stenobiella variola sp. n., a new species of beaded lacewing (Neuroptera: Berothidae), is described and figured from south-eastern Australia. A preliminary key to Stenobiella species is presented
Early processes involved in host recognition by arbuscular mycorrhizal fungi
Plant species that are hosts of non-arbuscular mycorrhizas were utilized to investigate the early processes involved in host recognition by arbuscular mycorrhizal fungi. The roots of plant hosts of ecto-, arbutoid and ericoid mycorrhizas, as well as those of non-mycorrhizal species, did not elicit the differential morphogenesis that occurred in the hyphae of Glomus mosseae (Nicol. and Gerd.) Gerd. and Trappe when challenged with the roots of its hosts. In the absence of this morphogenetic response, infection structures were not formed, any further step in the recognition process was hindered, and defence reactions did not occur. The ability of arbuscular mycorrhizal fungi to discriminate their specific hosts from all other plant species through a recognition process is probably determined by chemical signals
Microchambers and video-enhanced light microscopy for monitoring cellllular events in living hyphae of arbuscular mycorrhizal fungi
Mycelial elongation and protoplasmic flow rate in vitro were monitored for germinated spores of Gigaspora rosea and Glomus caledonium respectively, growing on membranes in microchambers, by using a combination of time-lapse and video-enhanced light microscopy and image analysis. The microchambers allowed continuous observation of living mycelium over a period of several hours during which protoplasm flow and bidirectional movements of cellular organelles and particles were monitored in individual hyphae. Growth rate of G. rosea hyphae, calculated 8 days after germination, was 2.64 μm/min. Protoplasmic flow rate, measured on the basis of the movement of particles, ranged from 2.98 to 4.27 μm/s in living hyphae of G. caledonium. We showed that G. rosea, when growing in axenic culture in the absence of the host, ceased growth within 8 days of germination and underwent a process of protoplasm retraction from hyphal tips, leading to the formation of empty mycelial segments. A process of resource reallocation was inferred in spores of G. rosea showing multiple germination. Detailed developmental studies of living hyphae by using microchambers could provide useful information on spatio-temporal dimensions of cellular events occurring in arbuscular mycorrhizal fungi
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TRICEPS: An ATMIS Field Implementation for Control and Evaluation: Final Report
This report summarizes a comprehensive research project directed toward the development and implementation of an Advanced Transportation Management and Information System (ATMIS) as part of the Caltrans Advanced ATMIS Testbed Program at the Institute of Transportation Studies, University of California, Irvine. The primary goal of this project was to implement this prototype ATMIS, designated TRICEPS (Testbed Realtime Integrated Control and Evaluation Prototype System), in the Irvine sub-area of the Advanced Testbed network. This sub-area represents a well-defined freeway corridor with a parallel major arterial alternative where traffic demand is predominantly along the corridor. This area, previously selected as the site for the federally-funded Irvine Field Operational Test to evaluate a centrally-controlled freeway/arterial corridor, thus provided an ideal environment in which to conduct the enhancements to and implementation of TRICEPS. The TRICEPS architecture allows for the introduction of a wide range of control and management capabilities; however, the focus of the initial implementation is the development and implementation of CARTESIUS, a real-time, multi-agent decision support system which integrates real-time control and simulation elements. The report provides background information on the genesis of TRICEPS, an overview of each of its major components and of the system architecture, the results of a system evaluation study, and a sample application of the model system
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