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Response to Invasion by Antigen and Effects of Threshold in an Immune Network Dynamical System Model with a Small Number of Degrees of Freedom
We study a dynamical system model of an idiotypic immune network with a small
number of degrees of freedom, mainly focusing on the effect of a threshold
above which antibodies can recognise antibodies. The response of the system to
invasions by antigens is investigated in the both models with and without the
threshold and it turns out that the system changes in a desirable direction for
moderate magnitude of perturbation. direction for moderate magnitude of
perturbation. Also, the propagation of disturbance by an antigen is
investigated in the system of one-dimensionally connected basic units taking
the closed 3-clone system as a unit, and it is clarified that the threshold of
the system has effects to enhance the stability of the network and to localise
the immune response.Comment: 6 pages, 6 figures. Submitted to Prog. Theor. Phy
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Characterization of the noble gases and CRE age of the D'Orbigny angrite
Introduction: The D’Orbigny angrite, a 16.55 kg stone, was found 1979 in Argentina [1]. Mineralogy and chemistry of this meteorite were characterized in detail [2-6]. A Pb-U-Th age of 4.559 Ga was obtained for pyroxenes by Jagoutz et al. [7]. Here we report results on the noble gas isotopic composition and, in particular, on the cosmic-ray exposure (CRE) age of D’Orbigny
A new clinical tool for assessing numerical abilities in neurological diseases: numerical activities of daily living
The aim of this study was to build an instrument, the numerical activities of daily living (NADL), designed to identify the specific impairments in numerical functions that may cause problems in everyday life. These impairments go beyond what can be inferred from the available scales evaluating activities of daily living in general, and are not adequately captured by measures of the general deterioration of cognitive functions as assessed by standard clinical instruments like the MMSE and MoCA. We assessed a control group (n = 148) and a patient group affected by a wide variety of neurological conditions (n = 175), with NADL along with IADL, MMSE, and MoCA. The NADL battery was found to have satisfactory construct validity and reliability, across a wide age range. This enabled us to calculate appropriate criteria for impairment that took into account age and education. It was found that neurological patients tended to overestimate their abilities as compared to the judgment made by their caregivers, assessed with objective tests of numerical abilities
Fraction of clear skies above astronomical sites: a new analysis from the GOES12 satellite
Comparing the number of clear nights (cloud free) available for astronomical
observations is a critical task because it should be based on homogeneous
methodologies. Current data are mainly based on different judgements based on
observer logbooks or on different instruments. In this paper we present a new
homogeneous methodology on very different astronomical sites for modern optical
astronomy, in order to quantify the available night time fraction. The data are
extracted from night time GOES12 satellite infrared images and compared with
ground based conditions when available. In this analysis we introduce a wider
average matrix and 3-Bands correlation in order to reduce the noise and to
distinguish between clear and stable nights. Temporal data are used for the
classification. In the time interval 2007-2008 we found that the percentage of
the satellite clear nights is 88% at Paranal, 76% at La Silla, 72.5% at La
Palma, 59% at Mt. Graham and 86.5% at Tolonchar. The correlation analysis of
the three GOES12 infrared bands B3, B4 and B6 indicates that the fraction of
the stable nights is lower by 2% to 20% depending on the site
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