Meridian Instrument (United States)

The article analyzes the benefits and drawbacks of the matrix of consequences and probability (ICAO risk matrix) as a method of safety risk assessment. The ICAO matrix is a qualitative method of risk management based on expert assessments of the degree of probability of individual possible events and of their consequences. The method is simple and easy to use, but can only assess separate differential risks. The article shows the failure of using the ICAO matrix for quantitative risk assessment of «past events» and deviations in the operational activity of the airline and getting an integrated risk of the airline and its monitoring. The article also describes the limitations of this method in solving the tasks of corrective measures prioritization in case of negative correlation between the probability and severity of consequences of events.

Recently we have reported that T-2 toxin, a trichothecene mycotoxin produced by Fusarium species, is a potent inducer of apoptosis in the human promyelotic cell line HL-60. To clarify the signal transduction pathway of apoptosis primed by T-2 toxin, T-2 toxin-induced apoptosis was investigated in detail using confocal laser microscopy and flow cytometry. Apoptosis in HL-60 cells induced by T-2 toxin was dose dependent when the cells were treated with concentrations of 5-100 ng/ml for more than 2 hr. The apoptosis proceeds through various cell cycle stages of HL-60 cells. Prior to apoptosis, the intracellular calcium ion (Ca+2i) level was markedly elevated within 3-5 min after exposure to T-2 toxin and returned to normal level thereafter. A well-known chelator for Ca+2i, ethylene-N,N,N', N'-tetraacetic acid 4K acetoxymethyl ester (BAPTA-AM), a Ca+2-dependent endonuclease inhibitor ZnCl2, and calpain inhibitor 1 sharply blocked T-2 toxin-induced apoptosis. These results strongly suggest that the Ca+2 signal triggered by T-2 toxin is transduced by the activation of endonuclease and protease, and ultimately evokes apoptosis.

This chapter addresses the use of ultraviolet (UV) light in confocal microscopy. We discuss both realized and potential advantages of UV-visible confocal imaging, as well as the special optical problems caused by the extension of the microscope’s wavelength range beyond the visible spectrum. Although this technology is new, a number of papers have appeared describing the use of both beam-scanning UV-confocal microscopes (Bliton et al., 1993; Fricker and White, 1992; Read et al., 1992; Lechleiter and Clapham, 1992; Kuba et al., 1991; Montag et al., 1991; Schubert, 1991; Ulfhake et al., 1991) and stage-scanning UV-confocal microscopes (Himpens et al., 1992).

Abstract The International Society for Photogrammetry held the XIIth International Congress at Ottawa during July and August 1972. The authors comprised a panel which engaged in discussion upon the Congress at a meeting of the Photogrammetric Society on 17th October, 1972.