9,701 research outputs found
Alien Registration- Gilbert, Marie (Fairfield, Somerset County)
https://digitalmaine.com/alien_docs/9543/thumbnail.jp
Ratio control in a cascade model of cell differentiation
We propose a kind of reaction-diffusion equations for cell differentiation,
which exhibits the Turing instability. If the diffusivity of some variables is
set to be infinity, we get coupled competitive reaction-diffusion equations
with a global feedback term. The size ratio of each cell type is controlled by
a system parameter in the model. Finally, we extend the model to a cascade
model of cell differentiation. A hierarchical spatial structure appears as a
result of the cell differentiation. The size ratio of each cell type is also
controlled by the system parameter.Comment: 13 pages, 7 figure
Incidence of symptomatic toxoplasma eye disease: aetiology and public health implications.
Ocular disease is the commonest disabling consequence of toxoplasma infection. Incidence and lifetime risk of ocular symptoms were determined by ascertaining affected patients in a population-based, active reporting study involving ophthalmologists serving a population of 7.4 million. Eighty-seven symptomatic episodes were attributed to toxoplasma infection. Bilateral visual acuity of 6/12 or less was found in seven episodes (8%) and was likely to have been transient in most cases. Black people born in West Africa had a 100-fold higher incidence of symptoms than white people born in Britain. Only two patients reported symptoms before 10 years of age. The estimated lifetime risk of symptoms in British born individuals (52% of all episodes) was 18/100000 (95% confidence interval: 10.8-25.2). The low risk and mild symptoms in an unscreened British population indicate limited potential benefits of prenatal or postnatal screening. The late age at presentation suggests a mixed aetiology of postnatally acquired and congenital infection for which primary prevention may be appropriate, particularly among West Africans
The Medea of Euripides
The programme was scanned from an original held in the University Archives.This play was produced under the direction of Patricia Hackett and was staged at The Hut from 25 - 28 October 1948
Comparative Analysis of Brass Wind Instruments With an Artificial Mouth: First Results
International audienceWe have developed in the past “artificial mouths” to study the behaviour of brass wind instruments (trumpet, trombone) in the playing situation, but without a musician. After using such devices to better understand the physical phenomena involved in brass instruments, we have built and used a new artificial mouth with the objective to test and set up instruments; the artificial mouth is considered here as a “test bench”. In this article, we describe the typical measurements that we have carried out on trumpets, in order to compare them (measurements of oscillation threshold, evolution of the playing frequency according to the dynamic level). As a first result, the artificial mouth allows one to show noticeable differences between instruments. We propose next some research paths which could be explored in order to better control the quality of instruments and, in the future, to introduce the use of an artificial mouth in the design process of brass instruments
Supersonic Line Broadening within Young and Massive Super Star Clusters
The origin of supersonic infrared and radio recombination nebular lines often
detected in young and massive superstar clusters are discussed. We suggest that
these arise from a collection of repressurizing shocks (RSs), acting
effectively to re-establish pressure balance within the cluster volume and from
the cluster wind which leads to an even broader although much weaker component.
The supersonic lines are here shown to occur in clusters that undergo a bimodal
hydrodynamic solution (Tenorio-Tagle et al. 2007), that is within clusters that
are above the threshold line in the mechanical luminosity or cluster mass vs
the size of the cluster (Silich et al. 2004). The plethora of repressurizing
shocks is due to frequent and recurrent thermal instabilities that take place
within the matter reinserted by stellar winds and supernovae. We show that the
maximum speed of the RSs and of the cluster wind, are both functions of the
temperature reached at the stagnation radius. This temperature depends only on
the cluster heating efficiency (). Based on our two dimensional
simulations (Wunsch et al. 2008) we calculate the line profiles that result
from several models and confirm our analytical predictions. From a comparison
between the predicted and observed values of the half-width zero intensity of
the two line components we conclude that the thermalization efficiency in SSC's
above the threshold line must be lower than 20%.Comment: 17 pages, 3 figures, accepted by Ap
ASU Formula Lightning Race Vehicle Report Prepared for Ohio Aerospace Institute
This report describes the drive system in the Arizona State University Formula Lightning electric race car when it participated in the 1994 Cleveland Electric Formula Classic on 9 July 1994. In addition, the telemetry system used to monitor the car's performance and plans for improving the car's performance are described
Force Feedback for Assembly of Aircraft Structures
Variability in composite manufacture and the limitations in positional accuracy of common industrial robots have hampered automation of assembly tasks within aircraft manufacturing. One way to handle geometry variations and robot compliancy is to use force control. Force control technology utilizes a sensor mounted on the robot to feedback force data to the controller system so instead of being position driven, i.e. programmed to achieve a certain position with the tool, the robot can be programmed to achieve a certain force. This paper presents an experimental case where a compliant rib is aligned to multiple surfaces using force feedback and an industrial robot system from ABB. Two types of ribs where used, one full size carbon fiber rib, and one smaller metal replica for evaluation purposes. The alignment sequence consisted of several iterative steps and a search procedure was implemented within the robot control system. The technology has the potential to lessen the need for dedicated tooling, reduce the need for traditional workspace calibration and can be used in several other applications, such as pin and socket type assemblies found in pylons or landing gear or 'part to part' assemblies such as leading edge ribs to spar
Periodic pattern formation in reaction-diffusion systems -an introduction for numerical simulation
The aim of the present review is to provide a comprehensive explanation of Turing reaction–diffusion systems in sufficient detail to allow readers to perform numerical calculations themselves. The reaction–diffusion model is widely studied in the field of mathematical biology, serves as a powerful paradigm model for self-organization and is beginning to be applied to actual experimental systems in developmental biology. Despite the increase in current interest, the model is not well understood among experimental biologists, partly because appropriate introductory texts are lacking. In the present review, we provide a detailed description of the definition of the Turing reaction–diffusion model that is comprehensible without a special mathematical background, then illustrate a method for reproducing numerical calculations with Microsoft Excel. We then show some examples of the patterns generated by the model. Finally, we discuss future prospects for the interdisciplinary field of research involving mathematical approaches in developmental biology
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