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The photoexcited Kα satellite spectra for Fe (Z = 26), Ni (Z = 28) and Zn (Z = 30) were measured with an x-ray crystal spectrometer using synchrotron radiation. The intensity variation of the KαL¹ satellite lines was obtained as a function of the excitation photon energy, from threshold to saturation. While the excitation energy increases, the continuous intensity rise from threshold to saturation could be explained by the shake-off process for inner-shell electrons of the medium-Z atoms. Applying the analytic Thomas model to the experimental data, the evolution of the KαL¹/Kα_1,2 intensity ratio, the threshold energy and the radius of the shake shell were determined.

High-resolution PIXE facilities (X-ray crystal spectrometers working on ion beams of accelerators) and their applications in chemical analysis and in basic research are surveyed.

A high-energy resolution PIXE system developed at a heavy ion microbeam line was used to analyze low energy X-rays below 1 keV. The system is equipped with a plane crystal spectrometer with a gas flow position sensitive proportional counter (PSPC), which enables high-energy resolution PIXE analysis using a microbeam. In order to improve the detection efficiency for the low energy X-rays, the X-ray entrance window of the PSPC was replaced with a thin polymer film supported by a metal grid. As the result, the detectable energy range was extended to carbon K X-rays and chemical effect in Fe and Cu L X-rays could be detected. A preliminary result of high-energy resolution PIXE mapping of Cu mesh (#500) showed that it is possible to obtain the Cu Lα mapping image using a 2 MeV proton microbeam with the size of 20×20 μm.

We have measured the yield of the sputtered ions from the surface of solid targets of conductive materials (Al, Ni, Cu, Ag, Si) bombarded by Xeq+(q=15–44) at 1.0 MeV (vp=0.55 a.u). The experiment was performed using micro-bunched highly charged Xe ion beams from CRYEBIS at Kansas State University. The secondary ions were detected and mass analyzed by a TOF spectrometer. The secondary ion yields showed a significant increase with increasing projectile charge state q, demonstrating the electronic sputtering in the interaction of slow highly charged ions with conductive materials. The increase rate became larger above q=26 compared to lower charge states, and showed a more prominent increase above q=35. These strong onsets of the increase rate at particular incident charge states can be attributed to the opening up of new inner shell holes in the incident highly charged ions. This is the first systematic observation of electronic sputtering of conductive materials using slow highly charged heavy ions bearing high potential energy.

A novel and potent antagonist of platelet-activating factor (PAF), Y-24180 (4-(2-chlorophenyl)-2-[2-(4-isobubylphenyl)ethyl]-6,9-dimethyl-6H-thieno[3,2-f][1,2,4]triazolo[4,3-a][1,4] diazepine) was investigated for the effects on the skin reactions induced by chemical mediators and the Arthus reactions. In the rat dorsal skin, Y-24180 (0.1–10 mg/kg, p.o.) inhibited increase in vascular permeability by the intradermal PAF injection in a dose dependent manner and the inhibitory activity was 60 times more potent than that of WEB 2086. While even at doses as large as 10 mg/kg, p.o., it had no effect on vascular permeability in the rat skin induced by histamine, serotonin, bradykinin and leukotriene D4. On a reversed passive Arthus reaction in rat dorsal skin, Y-24180 (0.1–1 mg/kg, p.o.) markedly inhibited vascular permeability in a dose dependent manner and the inhibitory activity was 15 times more potent than that of WEB 2086. Y-24180 also inhibited the Arthus dermal reaction in rabbits (0.03–0.3 mg/kg, p.o.) and guinea pigs (0.1–1mg/kg, p.o.). In addition Y-24180 (0.1–10 mg/kg, p.o.) significantly reduced the exudate volume and the number of infiltrated inflammatory cells in the reversed passive Arthus pleural reaction in rats. Furthermore, in rat passive Arthus pancreatitis, Y-24180 (0.3–10 mg/kg, p.o.) significantly inhibited the dye extravasation from the pancreas. These results provide strong evidence that endogenous PAF plays an important role as a mediator in the type III allergic inflammation.

Variable-energy (0–30 keV) positrons were used to study the depth distribution of heavy-ion induced vacancy type defects in the following specimens, SUS304 and SUS316 austenitic stainless steels, a SUS444 ferritic stainless steel and nickel metal, which were irradiated by 0.5 MeV He+, 2.0 MeV C+, 3.5 MeV Si2+ and 4.0 MeV Ni2+ ions up to 0.01 dpa at peak. Vacancy type effective residual defects (ERD) were evaluated from the line shape parameterS of Doppler broadened positron annihilation photon spectra. With increasing primary knockon atom (PKA) energy, a decrease of the vacancy type ERD was observed. The ERD differences among the specimens are discussed in comparison with theoretical predictions.

Nickel single crystal specimens were bombarded with various heavy ions, 0.2 MeV He+, 2.0 MeV C+, 3.5 MeV Si2+, 4.0 MeV Ni2+ ions, up to the same amounts of displacement per atom (dpa), and residual rate of defects in heavy-ion induced cascades was investigated by Rutherford backscattering (RBS) spectroscopy using channeling technique. Displacement damages are found to be variable with primary knock-on atom (PKA) energies, revealing a cascade quenching due to the recombination of point defects produced primarily. Residual rate of defects obtained experimentally are qualitatively in agreement with existing theoretical calculations.

ON-center and OFF-center receptive fields of cat retinal ganglion cells can be divided into two categories: sensitive (type N) and insensitive (type L) to three statistical temporal visual stimuli with different second order statistics but identical first order statistics (Tsukada et al. 1982). The temporal pattern sensitivity of type N response is closely related to the nonlinear stage of Y cells depending on the interaction between center and surround mechanism. The temporal pattern sensitivity of type N responses has a spatial profile within the receptive field; it is highly sensitive in the center region of the receptive field and less sensitive toward the field periphery. The temporal pattern sensitivity in the center region of the receptive field to statistical properties (irregular or regular) of a surrounding flash annulus shows modulation like a switching element: when the surrounding area is stimulated by a more regular flash stimulus with normal distribution of inter-stimulus intervals the system is sensitive (switching on) to the temporal pattern, while a change to an irregular one with an exponential distribution makes it insensitive (switching off) to the temporal pattern.

In order to characterize temporal pattern sensitivity in the cat ganglion cells, a new analysis technique by semi-Markov models which was developed in the previous papers (Tsukada et al., 1975–1977) was applied to input-output relations of the receptive-field. Three types of statistical spot stimuli positioned in the center region of receptive fields were used. Each type of stimulus has an identical histogram in the inter-stimulus intervals and therefore the same mean and variance, but different correlations between adjacent inter-stimulus intervals (Type 1, positive; Type 2, negative; and Type 3, independent processes). From the output spike trains of cat retinal ganglion cells to each stimulus, mean, variance, and histogram were computed. As the result of investigating these data, we could draw the following conclusion from the resultant output interval histograms. The receptive-field-center responses of cat ganglion cells can be classified into two groups (Types L and N) according to the difference of responsiveness to the three types of statistical spot stimuli. A Type L response has the same histogram in interspike intervals for all three stimuli, and is not sensitive to the temporal pattern, while a Type N response has three different forms depending on each type of stimulus showing high sensitivity to the temporal pattern. These results were also simulated by the Markov chain model and discussed with relation to neural coding and classification of ganglion cell types.

The characteristics of stored ions in a Kingdon trap have been investigated. The charge distribution of stored ions was measured by a time of flight (TOF) mass spectrometer. Storage of Arq+ (q = 1, 2, 3, 4) produced by electron beam irradiation has been confirmed. The dependences of Ar ion yields on the trapping potential and storage time have been systematically studied.Applying a voltage to end plates is very important for the storage of ions. Remarkable oscillations of the ion yields are found in the decay curves as a function of storage time for Ar+, Ar2+ and Ar3+ indicating periodical motion of each ion group about the central wire. The three dimensional orbits of ions in the trap are analysed by a computer calculation to understand the experimental results.

Abstract. Objective and Design: Effects of Y-24180 on antigen-induced asthmatic responses were evaluated in actively sensitized guinea pigs and the effects were compared with those of several anti-asthmatic drugs.¶Materials: Male Hartley guinea pigs were used.¶Treatment: Guinea pigs were actively sensitized with ovalbumin and were pretreated with pyrilamine. Y-24180 was orally administered to the animals 3 h and others were 1 h before the antigen challenge.¶Methods: The airway hyperresponsiveness was measured according to the method of Konzett and Rössler with some modifications. The immediate asthmatic response (IAR) and late asthmatic response (LAR) were measured by the oscillation method. Inflammatory cells infiltrated into the lungs were counted after the bronchoalveolar lavage.¶Results: Under oral administration before or after the challenge with antigen, Y-24180, OKY-046, and ONO-1078 suppressed the antigen-induced airway hyperresonsiveness. Moreover, Y-24180, ONO-1078, AA-2414, and theophylline suppressed both the IAR and LAR, but OKY-046 only suppressed the LAR. Among the test drugs, only Y-24180 and theophylline suppressed the antigen-induced accumulation of eosinophils in the bronchoalveolar lavage fluid.¶Conclusions: The data indicate practical participation of PAF in the development of antigen-induced asthmatic responses in animals, and usefulness of Y-24180 in the clinical treatment of asthma as well as other anti-asthmatic drugs.

We report the immunohistochemical localization of protein kinase C isozymes (types I, II, and III) in the rabbit retina using the monospecific monoclonal antibodies MC-1a, MC-2a, and MC-3a. Using immunoblot analysis of partially purified protein kinase C preparations of rabbit retina, types II and III isozymes alone were detected. The activity of type III was the stronger. By light microscopic immunohistochemical analysis, retinal neurons were negative for type I and positive for type II and type III isozymes. Type II was more diffusely distributed through the retinal layers, but was distinctive in ganglion cells, bipolar cells, and outer segments. The immunoreactivity was stronger for type III isozyme, and it was observed in mop (rod) bipolar cells and amacrine cells. By using immunoelectron microscopy, the cytoplasm of the cell body, the axon, and dendrites of the mop bipolar cells were strongly immunoreactive for type III. The so-called rod bipolar cells were for the first time seen to form synapses with rod photoreceptor cells. These differential localizations of respective isozymes in retinal neurons suggest that each isozyme has a different site of function in each neuron.

The aims of the New SUBARU project are to promote industrial applications in the VUV and soft X‐ray region and to develop research and development towards new light sources. The main facility of the New SUBARU project is the 1.5 GeV electron storage ring which is under construction at the SPring‐8 site in Harima Science Garden City, Japan. The storage ring is quasi‐isochronous and has variable momentum dispersion for the deep study of beam dynamics in very short bunches.

The phosphorylation of caldesmon was studied to determine if kinase activity reflected either an endogenous kinase or caldesmon itself. Titration of kinase activity with calmodulin yielded maximum activity at substoichiometric ratios of calmodulin/caldesmon. The sites of phosphorylation on caldesmon for calcium/calmodulin-dependent protein kinase II and endogenous kinase were the same, but distinct from protein kinase C sites. Phosphorylation in the presence of Ca 2+and calmodulin resulted in a subsequent increase of endogenous kinase activity in the absence of Ca 2+. These results suggest that caldesmon is not a protein kinase and that kinase activity in caldesmon preparations is due to calcium/calmodulindependent protein kinase II.

The phosphorylation of caldesmon was studied to determine if kinase activity reflected either an endogenous kinase or caldesmon itself. Titration of kinase activity with calmodulin yielded maximum activity at substoichiometric ratios of calmodulin/caldesmon. The sites of phosphorylation on caldesmon for calcium/calmodulin‐dependent protein kinase II and endogenous kinase were the same, but distinct from protein kinase C sites. Phosphorylation in the presence of Ca2+and calmodulin resulted in a subsequent increase of endogenous kinase activity in the absence of Ca2+. These results suggest that caldesmon is not a protein kinase and that kinase activity in caldesmon preparations is due to calcium/calmodulindependent protein kinase II.

Remarkable enhancements of the critical current density Jcwere obtained in polycrystalline La1.85Sr0.15CuO4with the splayed configuration of the columnar defects which were introduced by 3.5 GeV Xe ion irradiation with splay angles θ = 0°, ±5° and ±10°. In addition Jcincreased with the irradiation dose from 1.0×1011to 3.0×1011ions/cm2. Larger upward shift of the irreversibility line for the splayed configuration, in comparison with conventional parallel configuration, was observed. The results suggest that the vortex motion in La1.85Sr0.15CuO4is suppressed effectively by the splayed irradiation.

The behavior of vortex system in the presence of columnar defects in La1.85Sr0.15CuO4single crystal is studied by AC susceptibility measurements. It is found that the imaginary part χ″of the susceptibility as a function of temperature has a single peak, consistent with the Bose-glass theory, forBBcr, χ″exhibits double peaks, indicating the liquid-glass transition proceeds via two steps. The origin of the successive transitions is discussed.

Neurocalcin (molecular weight 23 000 and 24 000) is a Ca2+-binding protein with three putative Ca2+-binding domains and is present in large amounts in nervous tissues. Neurocalcin isoproteins separated by C18reverse-phase column chromatography are insoluble in buffer solution and it is impossible to determine the dissociation constant of neurocalcin with Ca2+. To overcome this difficulty, recombinant neurocalcin was synthesized, based on one of the cDNAs of the neurocalcin isoproteins. Stoichiometric titration experiments, using recombinant neurocalcin, indicated that this protein bound 2 mol Ca2+/mol protein and that the apparent dissociation constant for Ca2+was 2·2 μmol/l, suggesting that neurocalcin plays a physiological role in cellular function. Immunoblotting showed that neurocalcin is present in the bovine adrenal gland in addition to the nervous tissues. Neurocalcin, identified by immunoblotting, was purified from the bovine adrenal gland. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of neurocalcin from the bovine brain showed 23 kDa and 24 kDa double bands, while SDS-PAGE of neurocalcin from the adrenal gland showed a single band of apparently 24 kDa, suggesting that the expression of neurocalcin isoproteins differs from tissue to tissue. The content of neurocalcin in the adrenal gland was 10 μg protein/100 g wet tissue. Immunohistochemical analysis showed the occurrence of neurocalcin in zona glomerulosa and adrenal medulla but not in zona fasciculata or zona reticularis. The restricted localization of neurocalcin in the adrenal gland suggests that a similar Ca2+signal pathway may be present in zona glomerulosa and the adrenal medulla.Journal of Endocrinology(1993) 138,283–290