Dialogue Abner Shimony–Shimon Malin

Malin proposes a solution to some of the conceptual problems of the foundations of quantum mechanics within the framework of Alfred North Whitehead’s “Philosophy of Organism”. Standard quantum dynamics, governed by the time-dependent Schr?dinger equation, does not provide for the reduction of superpositions of physical states and hence does not account for occurrence of observational data. If consciousness is invoked to explain the results of measurements, it would appear that quantum mechanics is given an anthropocentric interpretation. Reduction of superpositions is achieved without anthropocentrism, according to Malin, by accepting Whitehead’s ontology of “actual occasions”, which are protomental entities independent of and presumably antedating human beings. Furthermore, Whitehead’s philosophy has the great virtue of offering a plausible solution to the profound problem of relating minds to material systems. Shimony is sympathetic to Whitehead’s world view, but with the reservation that it leaves an immense unexplained and unexplored gap between the conjectured “experience” of actual occasions and the high level experience of the human mind.QUPON/QIPC Special Issue     

Automatic identification of bacterial types using statistical imaging methods

The objective of the current study is to develop an automatic tool to identify microbiological data types using computer-vision and statistical modeling techniques. Bacteriophage (phage) typing methods are used to identify and extract representative profiles of bacterial types out of species such as the Staphylococcus aureus. Current systems rely on the subjective reading of profiles by a human expert. This process is time-consuming and prone to errors, especially as technology is enabling the increase in the number of phages used for typing. The statistical methodology presented in this work, provides for an automated, objective and robust analysis of visual data, along with the ability to cope with increasing data volumes.     

A Broadband Excimer-Halogen Emitter Utilizing Xenon Bromide and Iodide

The results are given of an investigation of the output characteristics of an electric-discharge excimer-halogen UV emitter utilizing a Xe/Br₂/J₂ mixture. A longitudinal glow discharge with an interelectrode spacing of 50 cm and inside diameter of the discharge tube of 1.4 cm is ignited at the working mixture pressure of 1 kPa and power input to the plasma of 10–350 W. A study is performed of the current-voltage characteristics of the discharge, plasma radiation spectra in the 190–350 nm range, and distributions of the brightness of radiation of molecules as a function of the pumping conditions, as well as of pressure and partial composition of the gas mixture. It is demonstrated that the plasma of the discharge being investigated is a source of broadband UV radiation in a system of bands of 253 nm XeJ, 282 nm XeBr, and 292–310 nm Br₂ ^*, which are joined by the radiation of resonance line of iodine atom with = 206 nm. The total power of UV radiation of plasma increases linearly with the electrical power of the glow discharge.     

Examining for possible non-thermal effects during heating in a microwave oven

The assumption that the thermal effect (heating) is the sole factor that should be considered when a microwave source is applied has been debated by many reports, often claiming that athermal (non-thermal) effects exist as well. Such effects are claimed to change the chemical, biochemical, or the physical behaviour of some systems while the temperature and all other parameters remain unaltered. The possibility of an athermal effect was tested in a number of chemical, biological and physical systems in a very well controlled, high radiation intensity system (2.45 GHz, up to 1000 W/kg, with continuous radiation up to 48 h). The systems that were tested included: Maillard reaction, protein denaturation and polymer solubility, mutagenesis of bacteria, mutarotation equilibrium of α/β-d-glucose, and saturation solubility of NaCl. All data failed to show any significant athermal effects. The results of this study are in contrast to what has been previously reported for some of the tested systems.     

Crystallization and morphology of isotactic poly(methyl methacrylates)

Several isotactic poly (methyl methacrylates) (iPMMA), with isotactic triad contents ranging from 46 to 100%, have been investigated after crystallization in the melt at different temperatures by differential scanning calorimetry, polarizing microscopy and small-angle light scattering. It was found that the crystallization of iPMMA, even of samples with high isotactic content, is slow. It never gives high degrees of crystallinity, but nevertheless leads to a spherulitic structure.     

A UV lamp based on a Kr-Xe mixture with Br2 and I2 molecules

A small-size broadband ultraviolet lamp with an emission spectrum of 206–390 nm, which is excited by a dc glow discharge, is described. The discharge was ignited in a quartz discharge tube with an inner diameter of 1.4 cm and an anode-cathode spacing of 10 cm. The tube was filled with a Kr/Xe/Br₂/I₂ working mixture, the total pressure being 0.5–2.0 kPa. The lamp’s emission spectrum consisted of a 206.2-nm iodine atomic line 0.1 nm wide at half-height and a continuum in a spectral region of 210–390 nm. The continuum resulted from overlapping of wide emission bands with peaks at 221 nm for XeBr(D-X), 253 nm for XeI(B-X), 282 nm for XeBr(B-X), 289 nm for Br ₂ ^* , 342 nm for I ₂ ^* , and 386 nm for IBr*. The total power of the ultraviolet emission was no more than 8–12 W, the power injected into the discharge being 10–100 W. The lamp lifetime in the gas-static mode was 300–400 h.     

Scaling approach to water sorption isotherms of hydrogels and foods

Mechanisms affecting water sorption isotherms of foods, at high water activities, were evaluated by the processes of swelling and shrinking of model systems of uncharged and charged hydrogels. Their water activity was found to be determined by the combined effect of their osmotic pressure and the network pressure of the polymeric network. The scaling approach in polymer science indicates that in an uncharged network the osmotic pressure is affected by the mobility of the polymer segments and thus by the degree of cross-linking. However, in charged gels, which behave in a similar manner to many food systems, the counterions play the dominant role in determining the osmotic pressure. The network pressure may shift from a positive to a negative value during shrinking (dehydration), thus counteracting or co-operating with the osmotic pressure in decreasing the water activity. A scaling sorption isotherm, at high water activity, is formulated for a food system with physically significant parameters.