Light, contrast control

Figure 12. Cell motility assay using the computer-controlled LCD images, (a) An image to measure the ratio of Tetrahymena trap. Trapped cells were marked with black arrows, (b) The ratios of aligned Tetrahymena according to the light contrast. At least five rephcates were conducted. (Reproduced with permission from Ref [25] Copyright 2008, American Institute of Physics.)...

Adjust the Field Diaphragm or Field Stop (FS, a second light intensity control after AS before 20/80 prism in the light path) to obtain the best contrast of adhering membranes or structures and background (Fig. lb and B , see FS). 

In contrast, various sensors are expected to respond in a predictable and controlled manner to such diverse parameters as temperature, pressure, velocity or acceleration of an object, intensity or wavelength of light or sound, rate of flow, density, viscosity, elasticity, and, perhaps most problematic, the concentration of any of millions of different chemical species. Furthermore, a sensor that responds selectively to only a single one of these parameters is often the goal, but the first attempt typically produces a device that responds to several of the other parameters as well. Interferences are the bane of sensors, which are often expected to function under, and be immune to, extremely difficult environmental conditions. 

More particularly, a serious breakthrough was achieved in the methods of electrochemical calorimetty. Initial conclusions as to anomalous heat evolution during the electrolysis of solutions prepared with heavy water were caused by an incorrect formulation of control experiments in light water. In fact, none of the communications confirming anomalous heat evolution have been free of procedural errors, so that one cannot even discuss a sporadic observation of this effect. In contrast to all other experimental manifestations, heat evolution is indicative of any possible nuclear transformation, which implies that in its absence, neither reaction (33.4.1) nor reaction (33.4.2) can be suggested to occur. 

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