The effect of the presence of foreign salts on the formation of gaseous ions for electrospray and laser spray

The effect of the presence of foreign salts (NaCl, aerosol OT, tetra-n-hexylammonium bromide, and CH3COONH4) on the formation of gaseous ions for electrospray (ES) and laser spray (LS) was studied in the positive and negative modes of operations. The ion signals for amino acids show sudden decrease with the concentration of foreign salts greater than 10(-5) M for both ES and LS. When the surface-active counter ions were added, the signal intensities showed a marked decrease for both ES and LS. This may be due to the enrichment of the surface-active counter ions on the surface of the charged droplets. When CH3COONH4 was added to an aqueous solution of 10(-6) M lysozyme chloride, an increase of the signal intensities for (lysozyme+nH)n+ and a decrease in the values of n were observed. The decrease in n may be due to the salt formation of (lysozyme+nH)n+ with the negative acetate ion leading to the reduction of positive charges.     

Listening difficulty as a subjective measure for evaluation of speech transmission performance in public spaces

Listening difficulty ratings, using words with high word familiarity, are proposed as a new subjective measure for the evaluation of speech transmission in public spaces to provide realistic and objective results. Two listening tests were performed to examine their validity, compared with intelligibility scores. The tests included a reverberant signal and noise as detrimental sounds. The subject was asked to repeat each word and simultaneously to rate the listening difficulty into one of four categories: (1) not difficult, (2) a little difficult, (3) fairly difficult, and (4) extremely difficult. After the tests, the four categories were reclassified into, not difficult [response (1)] and some level of difficulty, (the other 3 responses). Listening difficulty is defined as the percentage of the total number of responses indicating some level of difficulty [i.e. not (1)]. The results of two listening tests demonstrated that listening difficulty ratings can evaluate speech transmission performance more accurately and sensitively than intelligibility scores for sound fields with higher speech transmission performance.     

Non-destructive analysis of the two subspecies of African elephants, mammoth, hippopotamus, and sperm whale ivories by visible and short-wave near infrared spectroscopy and chemometrics

Visible (VIS) and short-wave near infrared (SW-NIR) spectroscopy was used for non-destructive analysis of ivories. VIS-SW-NIR (500-1000 nm) spectra were measured in situ for five kinds of ivories, that is two subspecies of African elephants, mammoth, hippopotamus, and sperm whale. Chemometrics analyses were carried out for the spectral data from 500 to 1000 nm region. The five kinds of ivories were clearly discriminated from each other on the scores plot of two principal components (PCs) obtained by principal component analysis (PCA). It was noteworthy that the ivories of the two subspecies of African elephants were discriminated by the scores of PC 1. The loadings plot for PC 1 showed that the discrimination relies on the intensity changes in bands due to collagenous proteins and water interacting with proteins. It was found that the scores plot of PC 2 is useful to distinguish between the ivories of the two subspecies of African elephants and the other ivories. We also developed a calibration model that predicted the specific gravity of five kinds of ivories from their VIS-SW-NIR spectral data using partial least squares (PLS)-1 regression. The correlation coefficient and root mean square error of cross validation (RMSECV) of this model were 0.960 and 0.037, respectively.     

Direct two-step spin-crossover through [HS-HS]...[LS-LS] at the plateau in dinuclear diiron(II) complex [{Fe(NCBH3)(4phpy)}2(mu-bpypz)2

The variable temperature magnetic susceptibility, X-ray crystallography, and IR and Raman spectra of a new dinuclear complex [{Fe(II)(NCBH(3))(4-phpy)}(2) mu-bpypz)(2)] demonstrated the first two-step spin-crossover associated with a 1 : 1 mixture of high-spin pair [HS-HS] and low-spin pair [LS-LS] at the plateau.     

Chaotic itinerancy in coupled dynamical recognizers

We argue that chaotic itinerancy in interaction between humans originates in the fluctuation of predictions provided by the nonconvergent nature of learning dynamics. A simple simulation model called the coupled dynamical recognizer is proposed to study this phenomenon. Daily cognitive phenomena provide many examples of chaotic itinerancy, such as turn taking in conversation. It is therefore an interesting problem to bridge two chaotic itinerant phenomena. A clue to solving this is the fluctuation of prediction, which can be translated as "hot prediction" in the context of cognitive theory. Hot prediction is simply defined as a prediction based on an unstable model. If this approach is correct, the present simulation will reveal some dynamic characteristics of cognitive interactions.     

Long-term effects of UV light on contractility of rat arteries in vivo

Several studies have shown that UV irradiation may be effective for preventing vascular restenosis or vasopasm. However, the long-term effects of UV light on the physiological properties of vessels such as arterial tension have not been elucidated. We therefore studied the long-term effects of UV using rat carotid arteries treated with UV-B light (wavelength = 313 nm, total energy = 14 mJ/mm2). The animals were sacrificed at 1, 7 and 14 days after UV light exposure, and the carotid arteries were studied by light microscopy and the contractile responses of isolated arterial rings were recorded under isometric tension. UV treatment had induced a substantial loss of smooth muscle cells (SMC) along the entire circumference of the media on days 7 and 14, whereas loss of SMC on day 1 was negligible. Contractile responses of arteries that had been exposed to UV light were significantly reduced on days, 1, 7 and 14. The susceptibility of UV-treated arteries to phenylephrine and prostaglandin F2 alpha was significantly decreased on days 1 and 7, but decreased susceptibility was not seen on day 14. Acetylcholine-induced relaxations were not altered by UV treatment. These results suggest that the long-term effect of UV light is an attenuation of smooth muscle contractility without impairment of endothelial function.     

Improvement of pharmaceutical potential of all-trans retinoic acid with hydroxypropyl-��-cyclodextrin

2-Hydroxypropyl-??-cyclodextrin (HP-??-CyD) includes all-trans retinoic acid (RA), covering the double-bond area of RA with substituted hydroxypropyl groups on CyD ring, as proved by the nuclear Overhauser effect (NOE) between methylene protons on the hydroxypropyl groups and the proton on RA. The formation of an inclusion complex results in hydrophilicity and stability. The effect of RA/HP-??-CyD and that of RA without HP-??-CyD on wrinkle scores and skin elasticity during skin treatment were identical, and the cutaneous stimulus was reduced comparing with RA. The results indicated that the RA/HP-??-CyD complex should help to realize new approaches in skin rejuvenation therapy.