Strong UV and weak visible continua of Zn2. Cd2 and ZnCd have been observed in emission when a discharge-excited atomic beam of zinc or cadmium is crossed with an unexcited beam of zinc or cadmium. It has been found that the discharge-excited beams of Zn and Cd contain also atoms in autoionizing states with lifetimes equal to (140 ± 30) and (110 ± 20) μsec, respectively.
Although there is an increasing evidence that the pineal gland may play a role in human malignancy, the studies on melatonin concentrations in different types of malignant tumors brought about controversial results. However, changes in melatonin concentrations have been observed in some types of human malignant tumors. Therefore, we decided to study the circadian melatonin rhythm in patients suffering from cervical cancer in different stages of progression and to compare them with those in subjects free from neoplastic disease. A total of 45 women were analyzed in this study. The subjects were divided into two groups. The first group consisted of 31 patients [mean age 52.1 +/- 1.8 yr (mean +/- S.E.M.), range 32-77 yr] with cervical cancer in various stages of the disease. The second group consisted of 14 healthy volunteers [mean age 53.5 +/- 2.0 yr (mean +/- S.E.M.), range 42-63] who served as the control group. Blood samples were collected at 08:00, 12:00, 16:00, 20:00, 22:00, 24:00, 02:00, 04:00, 06:00, and 08:00 hours. Melatonin concentration was measured by immunoenzymatic method. There were significant differences in circadian melatonin profiles as well as in the area under curve among the two studied groups. Melatonin concentrations were significantly lower in cancer patients in comparison with healthy individuals. Taking into consideration stage of the cervical cancer significantly lower melatonin secretion has been found in all subgroups of patients in comparison with that of tumor-free control group. Additionally, nocturnal melatonin concentrations as well as area under curve were significantly lower in advanced stage of cancer (stages 3 and 4) in comparison with patients with preinvasive cancer (stage 0) at 24:00, 02:00, and 04:00 hours and patients with stage 1 disease at 02:00 and 04:00 hours. The results of the present study indicate that the presence of cervical cancer influences melatonin levels in women. Moreover, stage dependence in reduction of melatonin concentrations has been found.
Optical spectra of ten AX+ ions (A=B, Al, Ga, In; X=F, Cl, Br) have been observed in the visible and near UV; a total of 18 band systems were newly discovered. The emission was produced by chemiluminescent reactions A++X2 at low (2–10 eVCM) kinetic energy in a beam-gas arrangement. A position-sensitive photon counting detector with large surface area and very low dark count rate was employed, the resolution was mostly 5–50 Å FWHM. Three types of band systems were observed: (1) For all AX+ combinations except BCl+ and BBr+, a very broad quasicontinuum with undulatory structure appears. On the basis of electronic state correlation arguments, photoelectron data, some ab initio calculations and, in one case, a known emission spectrum (InCl+) these band systems were identified as B 2Σ+–X 2Σ+ transitions. It is concluded that the excited state potentials are considerably displaced against the ground state, and their energetics are given. (2) For six species AX+, narrow band systems were observed in the 2500 Å region. They could be clearly identified as being due to C 2Π–X 2Σ+ transitions by means of comparison with the systematics of the analogous A 2Π–X 2Σ+ transitions of the isoelectronic alkaline earth halides, by the resolved fine structure, and, in the case of AlF+, by an ab initio calculation. (3) In the GaCl+, GaBr+, and InBr+ spectra, narrow features accompany the C–X transitions. They are attributed to D 2Σ+–X 2Σ+ transitions, analogous to the alkaline earth halide B 2Σ+–X 2Σ+ band systems. Qualitative electronic state correlations are discussed, and the expected dominant configurations in different regions of the AX+ ground and excited states are given. These are in accord with recent ab initio results on AlF+.
Chemiluminescent reactions of C( 3 P) atoms and C + ( 2 P) ions with NH 3 were investigated in the 12-1000 eV Lab (7-586 eV CM ) energy range, using a beam/gas arrangement. The fast carbon atoms were generated from C + ( 2 P) ions by near-resonant charge transfer with CCl 4 . The reaction products NH(A 3 Π), CN(B 2 Σ + ), and CH(A 2 ∆) were studied by means of the NH(A-X), CN(B-X), and CH(A-X) emission spectra at 1.4 and 0.35 nm fwhm resolution. Besides, traces of NH(c 1 Πa 1 ∆), CH(B 2 Σ --X 2 Π), and Balmer line emission were also observed. The reactions were classified as follows: (a) CH(A) is formed by exchange reactions, which are assisted by a hard-sphere-collision mechanism at high energies to moderate the kinetic energy; (b) NH(A) and NH(c) originate at low energies from substitution reactions, and NH(A) also results from collisional dissociation at high energies; (c) CN(B) is formed (only at low energies) via a long-lived [C-NH 3 ] + complex. Detailed evidence for these assignments came from the observed spectra, which were analyzed by means of a computer simulation, as well as from measurements of the energy-dependent relative cross sections.
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