A microchip capillary electrophoretic reactor: a new methodology for direct measurement of dissociation kinetics of metal complexes

A microchip capillary electrophoretic reactor has been proposed and successfully demonstrated in the direct evaluation of the solvolytic dissociation rate constant of the complex of Ce3+ with a polyaminocarboxylic ligand, 8-amino-2-[(2-amino-5-methylphenoxyl)methyl]-6-methoxyquinoline-N,N,N',N'-tetraacetic acid.     

Efficacy of spectral presaturation of inversion recovery in evaluating delayed myocardial enhancement

OBJECTIVE: Delayed myocardial enhancement is caused by a variety of cardiovascular diseases. The extent of the enhanced area has been examined by the inversion recovery (IR) method, whereby at the inversion time (TI), normal myocardium shows a low signal intensity. In this sequence, as pericardial fat shows a very high intensity, a delayed enhancement just below the pericardium may be indistinct. To improve the accuracy of delayed myocardial enhancement, we employed the spectral presaturation of inversion recovery (SPIR) method. MATERIALS AND METHODS: Thirty-five patients with symptoms of cardiovascular disease aged between 36 and 80 years old (mean age, 62 years old) were investigated. Thirty were men and five were women. Inversion recovery and SPIR images were obtained 25 min after initial administration of a gadolinium-based contrast material. Each TI, when the signal intensity of the normal myocardium was null, was determined by images obtained at serial different TIs. A radiologist and a cardiologist examined each image by a consensus reading. The extent of myocardial enhancement was described as none, subendocardial, transmural and a random pattern in each case. Images were ranked over three levels and were based on whether myocardial enhancement could be easily detected or whether the contour of the myocardium was visualized precisely. Student's t-test was conducted to compare the quality of two sequences in all patients and in 22 patients who showed delayed myocardial enhancement. RESULTS: The imaging quality in evaluating delayed myocardial enhancement in all patients was superior with IR compared with SPIR, although it was not statistically significant. The imaging quality in the patients with delayed myocardial enhancement was similar between SPIR and IR. SPIR was superior to the IR sequence in two of the four patients who exhibited transmural enhancement. CONCLUSION: SPIR exhibited equivalent image quality to IR in evaluating delayed myocardial enhancement. As it has the potential advantage in patients with rich adipose tissue surrounding the myocardium, it can be an alternative sequence to evaluate myocardial viability.     

Synthesis of a protein biosynthesis inhibitor, 5′-tri-phosphoryladenylyl-(2′-5′)-adenosine

A protein biosynthesis inhibitor, 5′-triphosphoryladenylyl-(2′-5′)-adenylyl-(2′-5′)-adenosine was synthesized by polymerization of N⁶-benzoyl-3′-O-(o-nitrobenzyl)adenosine 5′-phosphate follwed by reaction with pyrophosphate using 1,1′-carbonyldiimidazole.     

The influence of mode-coupling on the degree of coherence in an optical fiber

The modulus of the complex degree of coherence across the exit face of a coherently excited optical fiber is investigated by taking account of coupling effects between propagating modes. We also discuss the results of numerical calculations for a quasi-single mode fiber. The modulus exhibits an oscillatory behaviour along the fiber length if coupling or beating is present. The oscillatory modulus is found to be large compared with the value it would assume if the cross-terms were neglected.     

Effects of Spatial Coherence and Dispersive Diffraction on a Change in Optical Spectrum

This paper describes a change in optical spectrum on propagation in free space for a particular class of spatially partially coherent fields emanating from a polychromatic secondary source. A rectangular opening aperture in an opaque screen, illuminated with an extended incoherent polychromatic primary source, works as the secondary source. The spectral change is explored in detail theoretically and experimentally in association with spatial coherence in the secondary source as well as dispersive diffraction by the secondary source. The peak shift of the spectrum is associated with the coherence area for characterizing the secondary source. The peak shift becomes maximum if the secondary source is spatially coherent, but no shift occurs if the secondary source is spatially incoherent.     

New visualization method of progressive acoustic wavefronts using a Köster prism

Visualization of a progressive acoustic wave is explained and verified experimentally. A Köster prism set in an image-forming system works so that the optical wave fields emerging from two points across the exit plane of an acoustic column may be superposed at a point in the image plane. The image intensity changes with a period of half the acoustic wavelength magnified suitably. The visibility of the image intensity takes values between 0 and 0.54 if the acoustic power is made to change. No practical frequency limitation is present in the lower frequency range of the acoustic wave.