INTRODUCTION Although anecdotal reports of G-induced loss of consciousness (G-LOC) in military aviation date back to before 1920, regular reporting did not begin until 1982. The effectiveness in the operational setting of G-LOC preventive measures, such as positive pressure breathing for G protection (PBG), has not been studied. METHODS We use the term "crash" to represent an event where the ...

Acute intermittent porphyria (AIP) is a primary disorder of haem biosynthesis that is chemically characterised by raised urinary porphobilinogen (PBG). A defect in the biochemical pathway at the step of PBG conversion to uroporphyrinogen has been shown to be a result of a partial deficiency of the enzyme uroporphyrinogen I synthetase (uro I syn). The ascertainment rate of latent AIP (that is, c...

This paper is a survey of our recently published and new results on nonlinear-optical studies of photonic band-gap (PBG) structures formed from mesoporous silicon. The studies are performed on photonic crystals, high-quality-factor microcavities (MC) with a half-wavelength-thick microcavity spacer, and on series of coupled microcavities with two identical microcavity spacers and controllable co...

Here we demonstrate a novel quantitative procedure to pursue statistical studies on the geometric properties of photonic crystals and photonic quasicrystals (PQCs) which consist of separate dielectric particles. The geometric properties are quantified and correlated to the size of the photonic band gap (PBG) for wide permittivity range using three characteristic parameters: shape anisotropy, si...

An 11.4 GHz photonic band-gap (PBG) structure where the rods in the inner row have an elliptical cross-section has been designed at MIT and manufactured and tested at high power and high repetition rate at SLAC. This structure exhibits lower surface magnetic fields on the rods relative to previous PBG structures tested at SLAC, which reduces the ohmic heating of the rod surface in an effort to ...

This report demonstrates the ability of folic acid to activate rat liver porphobilinogen-deaminase (PBG-D). Lineweaver-Burk analysis revealed an increase in Vmax (38%) without affecting the Km. In the concentration range assayed, secondary replots of 1/delta slope and 1/delta intersect versus 1/[folic acid] yielded straight lines, indicating the binding of a single molecule of activator to the ...

Photonic band gap (PBG) dielectric fibers with hollow cores are being studied both theoretically and experimentally for use as laser driven accelerator structures. The hollow core functions as both a longitudinal waveguide for the transverse-magnetic (TM) accelerating fields and a channel for the charged particles. The dielectric surrounding the core is permeated by a periodic array of smaller ...

The investigation of the photochemistry of a two-stage photobase generator (PBG) is described. Absorption of a photon by a latent PBG (1) (first step) produces a PBG (2). Irradiation of 2 in the presence of water produces a base (second step). This two-photon sequence (1 + hν → 2 + hν → base) is an important component in the design of photoresists for pitch division technology, a method that do...

Abstract Effective instruction and assessment are greatly affected by many factors. The ever-growing literature on outlined some cognitive, social, emotional factors that directly or indirectly influence the learners’ academic achievement. In spite of rosy assessment, possible interplay among Core Self-assessment (CSA), Student Evaluation Apprehension (SEA), Personal Best Goal (PBG), Self-effic...

AIM To investigate the effect of a macro-nutrient preload (Inzone Vitality) on blood glucose levels and pregnancy outcomes of gestational diabetes. The preload method involves the ingestion of a smaller amount of a macronutrient composition half an hour before regular meals. The hypothesis was that preload treatment will reduce postprandial glycemia in gestational diabetes. METHODS Sixty-six ...