Synthesis and characterization of polymers with pendent phosphonate groups

Soluble chloromethylated polystyrene and its copolymers with vinylidene chloride as well as poly(phenyl oxides) brominated in the side chains and in the ring were synthesized and characterized in detail by NMR. The halogenated polymers were phosphonylated with alkyl phosphites. Uncrosslinked polymers with pendent phosphonate groups were prepared in the presence of etheral solvents, which solvate the ionic intermediates of the Arbuzov reaction. These polyphosphonates are highly hygroscopic and are soluble in a variety of solvents. Their T_g's are in the range of 50–175°C. Their thermal behavior was analyzed on the basis of thermogravimetric measurements combined with mass-spectrometric analysis. Poly(styrene phosphonate) seems to be the most stable, and its thermal decomposition starts at ～330°C. The polymeric phosphonates are compatible with an unusually large number of polymeric systems and seem to form “true” polymeric alloys with acetylcellulose.     

Theodor Reik: On psychoanalysis and the unconscious compulsion to confess.

In 1924, Theodor Reik presented a series of lectures in Vienna, which resulted in the publication of the book, The Compulsion to Confess (1925/1959). It was Reik's claim that his conceptualization of the unconscious compulsion to confess was a "discovery" and suggested that it be incorporated in the theory and lexicon of classical psychoanalytic theory. It is from the socialization experiences of the child (the modification of instinctual impulses) that repression is experienced and thus the process of confession is an attempt to quell (unconsciously) feelings of guilt and need for self-punishment. The power of a hostile superego plays the pivotal role, according to Reik, in the development of the neurosis, and it is within the framework and dynamics of the Oedipal complex that unconscious confessions result. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Preparation of inner salt polymers from vinylimidazolium sulphobetaines

The preparation and properties of ampholytic polymers has been a relatively unexplored area. In this work are discussed the syntheses of monomeric vinylimidazolium sulphobetaines, a class of aromatic inner salt monomers, their free radical polymerizations, and the properties of the resulting polymeric inner salts. Several of the ampholytic polymers prepared were shown to have hydrogel characteristics.     

On radio-wave propagation in forest environments

Propagation of electromagnetic waves in forest environments at medium and high (1-100 MHz) frequencies is examined for the case where both the transmitting and receiving points are situated within the vegetation. A dissipative slab in the presence of a reflecting ionosphere is employed to describe the forest configuration. If the effect of the ground-forest interface is disregarded, the radiated field of an arbitrarily oriented, small dipole is found to consist primarily of two separate waves: a lateral wave which skims along the tree tops, and a sky wave which is produced by a single-hop reflection at the ionospheric layer. These two field constituents are compared and their domains of preponderance are calculated for a large range of the pertinent parameters; it is then found that the lateral wave plays the major role since the sky wave is restricted to a narrow frequency band and its amplitude is appreciable only at large distances. The lateral-wave field is examined in detail and is shown to yield a simple physical picture for the propagation mechanism in forests. Its features are found to be qualitatively consistent with the field behavior reported in the literature and the quantitative aspects agree well with the available experimental data. The observed variation of the field with distance, the height-gain effect, the vegetation factor, the basic path loss, and depolarization effects are separately examined and are all shown to express merely one or another of the intrinsic properties of a lateral wave. The ground-proximity effect produced by the presence of a planar-conducting ground is also estimated and shown to be of minor importance in most cases.     

Lyme disease in outdoor workers on Assateague Island: high tick-exposure but low disease risk

Endothelin-1 (ET-1)-converting enzyme (ECE) activity in the human serum lipoprotein fraction was studied using a sensitive enzyme immunoassay and reverse-phase high performance liquid chromatography. The ECE activity of cleaving synthetic human big ET-1 into ET-1 by the serum lipoprotein fraction was about 14-times greater than that by whole serum, and the activity was closely associated with lipoprotein itself. The lipoprotein ECE activity, which was optimal at pH 7.0, was inhibited by EDTA, o-phenanthroline, phosphoramidon, thiorphan, phenylmethanesulfonyl fluoride and chymostatin, but not by cysteine or aspartic proteinase inhibitors, suggesting metalloproteinase- and chymotrypsin-like properties. These results suggest that the serum lipoprotein ECE may be involved in the processing of big ET-1 to ET-1 in the circulatory system.     

On lateral waves in slab configurations and their relation to other wave types

The customary analysis of radiation from sources in the presence of a dielectric slab involves a plane-wave superposition wherein the boundary conditions are satisfied by a single composite reflection coefficient. The far field is then comprised of the incident and reflected waves as well as a diffracted contribution of surface and leaky waves (pole waves). An alternative formulation is discussed wherein the interface effects are accounted for one at a time and the resulting diffraction field is then shown to involve lateral waves (branch-cut waves). The two representations are compared and their respective utility is illustrated by examples. When the source and observation points are located exterior to a large dielectric gap, diffraction effects due to an accumulation of leaky waves are found to be equivalent to a single lateral wave. For source and observation points inside a lossy dielectric slab, the pole-wave formulation provides a somewhat more convenient but physically less transparent result than the one comprising lateral waves.     

FREQUENCY DEPENDENCE IN DIELECTROPHORESIS: TRAJECTORIES AND PARTICLE BUILDUP

A study of the effect of frequency of a sinusoidal field on dielectrophoretic capture is presented, using numerical analysis to compute particle trajectories. It is shown that at certain critical frequencies the trapping efficiency drops sharply due to weakening of the dielectrophoretic pull. Experiments in which the capture performance was visually recorded by photographing the particle buildup on a single rod at increasing frequencies are reported. Results are discussed in the light of the numerical analysis.     

Scaling procedures for specifying color appearance

Colors of objects are often specified by color matches in some standard colorimetric system. While color-matching allows a color to be reproduced accurately, it does not specify what the color actually looks like. Color appearance (i.e., hue, saturation, brightness) can be measured by direct psychophysical scaling techniques; however, these methods have not been standardized and have been confined mostly to the laboratory. We have examined several variants of continuous, numerical scaling of hue and saturation to find a procedure that is usable, even by untrained observers. Appearances of monochromatic, equal-luminance light flashes were scaled along the dimensions of the unique hue sensations (red, yellow, green, blue) and apparent saturation. These functions were obtained for various stimulus conditions, including changes in stimulus luminance, size, and eccentricity. Multidimensional scaling methods were used to derive metrically uniform color appearance diagrams from the hue and saturation scaling data. Validity of the scaling procedures was assessed by deriving well-known visual functions, such as wavelength discrimination, from the color appearance diagrams. The direct scaling method was shown to be generally useful, and both trained and untrained observers readily and reliably used the technique.