Spectral density of millimeter wave amplitude scintillations in an absorption region

A detailed theory including the effect of water vapor fluctuations for the spectral density of the log amplitude scintillations of a radio wave propagating in an absorption medium is presented. The scintillation spectra obtained from links at 55.5 and 36.1 GHz on a common 4.1 km path are given together with the relevant meteorological data. Results show that the lower corner frequency predicted by Ott and Thompson, for the enhancement of the scintillations in an absorption region, is a good approximation.     

Ryanodine action at calcium release channels. 1. importance of hydroxyl substituents

Ryanodine (1) and dehydroryanodine (2) have a polar face formed by cis-hydroxyls at C-2, C-4, C-6, and C-12. The importance of the hydroxyls to the action of 1 and 2 at the ryanodine receptor (ryr) of calcium release channels is examined at [3H]-1 binding sites in brain and skeletal muscle and in heart membranes relative to cardiac contractility, a pharmacologic response which appears to be mediated by the ryr. Five types of changes are considered: blocking the 4- and 6-hydroxyls as cyclic borates and boronates; blocking the 10- and 12-hydroxyls as cyclic phosphates, phosphonates, and phosphoramidates; methylation at nitrogen or hydroxyls at C-4 and C-10; dehydration of the C-2 hydroxyl; additional data for a 4,12-oxygen-bridged series. The first change has little effect on potency possibly due to the lability of the boron protective groups whereas the cyclic phosphorus compounds have reduced activity. Methylation reduces potency the least at nitrogen and the C-4 hydroxyl. Dehydration of 1 to 2-deoxy-2(13)-dehydro-1 allows the restoration of oxygen at C-2 by conversion to epoxides or a diol. One of the epoxides and 2-deoxy-2(13)-dehydro-2 retain 8-31% of ryanodine's potency in the ryr assays and 81% in the cardiac contractility system. In the 4,12-oxygen-bridged series, high potency at the receptor and cardiac muscle is retained in the 4-hydroxy ketal.     

Characterization of molecular orientation in injection–stretch–blow‐molded poly(ethylene terephthalate) bottles by means of external reflection infrared spectroscopy

The molecular orientation at the outer surface of injection–stretch–blow‐molded bottles made from poly(ethylene terephthalate) was characterized and quantified by means of front‐surface reflection infrared spectroscopy based on a method developed previously. Results were obtained for two different bottle shapes (cylindrical and rectangular) molded at different injection mold temperatures (16, 38, and 60°C). For the cylindrical bottles, the preferred molecular chain orientation was found to be in the axial direction, with the Hermans orientation function near 0.3 for all three mold temperatures. For the less symmetrical rectangular bottles, a significant difference was observed between the large and small faces. For the large face, the orientation was mainly in the hoop direction; the Hermans orientation function was in the range of 0.3–0.5 and was essentially the same at all mold temperatures and positions along the bottle height. For the small face, on the other hand, the preferred orientation changed from the hoop direction near the bottom to the axial direction near the top, and the variation was more pronounced at lower mold temperatures. The utility of the front‐surface reflection technique was clearly demonstrated. It was also applied, with the use of an infrared microscope, to examine the orientation gradient across the wall thickness. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1319–1327, 2007     

Dare to Dream: Bringing Futures into Planning

Futures studies and planning follow parallel and sometimes overlapping paths. Both are idealistic activities seeking to make people's futures more secure and more fulfilling. Many futurists wish that their dreams could be implemented, and many planners dream that their work could be less shortsighted and parochial. If only to fulfill these needs, these groups should pay more attention to each other. In this article, I attempt to strengthen the bridge between futurists and planners. My observations come from the perspective of someone with a professional and pedagogical interest in both planning and futures studies. I illustrate past, current, and potential contributions of futures studies to planning as follows: (1) the beginnings of futures studies in science fiction films, journals, and international development; (2) the role of envisioning, polling, and forecasting methods; and (3) the challenges of linking futures studies methods to planning. I then argue for a diverse approach in terms of methods and participants and assert that if planners are to embrace the future, their plans must begin with the future.