Crystallographic and electronic properties of AlCrN films that absorb visible light.

We investigate the crystallographic and electronic properties of wurtzite Cr-doped AlN (AlCrN) films (Cr ≤12.0%) that absorb visible light. We confirmed that the films consist of wurtzite columnar single crystals that are densely packed, c-axis oriented, and exhibit a random rotation along the a-axis in plane by using transmission electron microscopy. The oxidation state of Cr was found to be 3+ using Cr K-edge X-ray absorption near edge structure, which implies that Cr can be a substitute for Al3+ in AlN. The first nearest neighbor distances estimated using Cr K-edge extended X-ray absorption fine structure (EXAFS) were found to be nearly isotropic for incident light with electric fields that are parallel and perpendicular to the plane. The results of ab initio lattice relaxation calculations for the model of wurtzite Al1-xCrxN supercell where Cr replaces Al support the EXAFS results. The calculations for the model showed that additional energy bands are formed in the band gap of AlN, in which the Fermi energy (EF ) is present. As expected from the calculation results, the electrical conductivity increases with increase in the Cr concentration, implying that the density of states at EF increases monotonically. From these results, we can conclude that AlCrN films are an intermediate band material with respect to their crystallographic and electric properties.

Electronic structure of AlCrN films investigated using various photoelectron spectroscopies and ab initio calculations.

The valence band (VB) structures of wurtzite AlCrN (Cr concentration: 0-17.1%), which show optical absorption in the ultraviolet-visible-infrared light region, were investigated via photoelectron yield spectroscopy (PYS), x-ray/ultraviolet photoelectron spectroscopy (XPS/UPS), and ab initio density of states (DOS) calculations. An obvious photoelectron emission threshold was observed ~5.3 eV from the vacuum level for AlCrN, whereas no emission was observed for AlN in the PYS spectra. Comparisons of XPS and UPS VB spectra and the calculated DOS imply that Cr 3d states are formed both at the top of the VB and in the AlN gap. These data suggest that Cr doping could be a viable option to produce new materials with relevant energy band structures for solar photoelectric conversion.

Ce electronic states in Nd(0.45-x)Ce(x)Sr0.55MnO3 probed by x-ray absorption spectroscopy and photoemission.

We have investigated the Ce 4f electronic states in the Ce-doped manganites Nd(0.45-x)Ce(x)Sr0.55MnO3 (NCSMO) by means of x-ray absorption spectroscopy (XAS) and hard x-ray photoelectron spectroscopy (HAXPES). The Ce 3d XAS shows that the Ce ions exist in the form of the Ce(3+) and Ce(4+) mixed-valent states, and we have found that the XAS spectral features change with temperature. The Ce 3d XAS and HAXPES spectra for NCSMO agree reasonably well with calculated results based on the single-impurity Anderson model, which takes into account the atomic multiplets and two valence bands. The estimated Ce bulk valence of Nd0.15Ce0.3Sr0.55MnO3 decreases from 3.44 to 3.30 with cooling.

Coexistence of strongly mixed-valence and heavy-fermion character in SmOs4Sb12 studied by soft- and hard-X-ray spectroscopy.

Sm-based heavy-fermion compound SmOs4Sb12 has been investigated by soft x-ray (hnu=1070-1600 eV) and hard x-ray (HX; hnu=7932 eV) spectroscopy. The HX photoemission spectroscopy clearly demonstrates that the strongly mixed-valence state and the heavy-fermion state coexist in the bulk. It is found that the Sm valence decreases below 100 K, indicating that the Kondo coherence develops with approaching the proposed Kondo temperature. Our theoretical analyses suggest that the origin of the coexistence in SmOs4Sb12 is the coincidence of two conditions, namely, (i) the energy difference between Sm divalent and trivalent states is very small and (ii) the hybridization between Sm 4f and conduction electrons is weak.

Three-dimensional bulk fermiology of CeRu2Ge2 in the paramagnetic phase by soft x-ray hnu-dependent (700-860 eV) ARPES.

By virtue of the soft x-ray angle-resolved photoelectron spectroscopy, the three-dimensional bulk fermiology has been successfully performed for a strongly correlated Ce compound, ferromagnet CeRu2Ge2 in the paramagnetic phase. A clear difference of the Fermi surface topology from either band calculation or de Haas-van Alphen results in the ferromagnetic phase is observed and interpreted by considering the difference of the 4f contribution to the Fermi surfaces in the paramagnetic phase.

Mutual experimental and theoretical validation of bulk photoemission spectra of Sr1-xCaxVO3.

We report high-resolution high-energy photoemission spectra together with parameter-free LDA + DMFT (local density approximation + dynamical mean-field theory) results for Sr1-xCaxVO3, a prototype 3d(1) system. In contrast to earlier investigations the bulk spectra are found to be insensitive to x. The good agreement between experiment and theory confirms the bulk sensitivity of the high-energy photoemission spectra.

Localized character of 4f electrons in CeRhx (x=2,3) and CeNix (x=2,5).

We have measured Ce 4f spectral weights of extremely alpha-like Ce transition metal intermetallic compounds CeRhx (x=2,3) and CeNix (x=2,5) by using the bulk-sensitive resonant photoemission technique at the Ce M5(3d(5/2)-->4f) edge. High energy resolution and longer escape depth of photoemitted electron at this photon energy enabled us to distinguish the sharp Kondo resonance tails at the Fermi level, which can be well described by the Gunnarsson-Schönhammer calculation based on the Anderson impurity Hamiltonian. On the other hand, the itinerant 4f band description shows big discrepancies, which implies that Ce 4f electrons retain localized characters even in extremely alpha-like compounds.

Enhancement of sweetness ratings of aspartame by a vanilla odor presented either by orthonasal or retronasal routes.

When taste stimuli are presented with specific odor stimuli, the perceived intensity of taste is enhanced, a phenomenon called odor-induced taste enhancement. There is a possibility, however, that the odor substances might have stimulated the taste receptors in the oral cavity as well as odor receptors in the nasal cavity because the odor substances were dissolved in the taste solutions in some preceding studies. Schifferstein and Verlegh (1996) found that the odor-induced taste enhancement effect was not found when the subjects wore a nose clip to prevent the olfactory perception. Thus, it was suggested that the odor-induced taste enhancement did not result from the stimulation of receptors in the oral cavity. To confirm and extend their study, we presented the odor stimuli simultaneously with, but not dissolved in, the taste stimuli with a more advanced approach to stimulus presentation. The participants reported enhancement of sweetness ratings for aspartame when the taste stimuli were presented with a vanilla odor. This odor induced taste enhancement was found when the gaseous odor stimuli were presented either by the retronasal route or by the orthonasal route. There was little possibility that the vanilla odor stimulated the taste receptors during the orthonasal stimulation because the odor stimuli were presented directly into the nasal cavity. Thus, we could show that the odor-induced taste enlancement is elicited by olfactory perception. These results also suggested that there is little functional difference between retronasal and orthonasal olfaction.

High-resolution soft X-ray absorption spectroscopy of solids.

The present research deals with the high-resolution soft x-ray absorption spectra (XAS) of Si, Ce- and Sm- compounds measured at BL25SU of SPring-8. The spectra are compared with theoretical results. The Si 1s spectrum shows good agreement with the calculated empty density of states so far reported. The Ce 3d spectra are very sensitive to the local electronic structure. The Sm 3d XAS of SmS shows clear temperature dependence, which is partly explained by a calculation for Sm2+ ion.

Magnetic circular dichroism at transition metal L2,3 edges in D03-type (Fe(1-x)Mn(x))3Al alloys.

We have measured magnetic circular dichroism (MCD) spectra at the transition-metal L2,3 edges in D03-type (Fe(1-x)Mn(x))3Al in order to investigate their local magnetic moments. The analysis of the spectra shows that Fe has moments much larger than Mn, whose moment is ferromagnetically coupled with the Fe one. This does not lend support to the antiferromagnetic mechanism proposed for the reduction in magnetization as well as a large Mn moment predicted for x = 1/3. The evolution of satellites found in the Mn spectrum with x increased suggests that the change in the electronic state may result in the magnetization reduction.

Magnetic circular dichroism at transition metal L2,3 edges in D03-type (Fe(1-x)Vx)3Al alloys.

Magnetic circular dichroism (MCD) spectra have been measured at the Fe and V L2,3 edges of DO3-type (Fe(1-x)Vx)3Al in order to investigate their local magnetic moments and electronic structures. Large MCD is observed at the Fe L2,3 edges, while the V L2,3 MCD shows relatively small intensity with complicated features. Signs of these MCD spectra indicate an antiferromagnetic coupling between the magnetic moments on Fe and V. According to the analysis based on the magneto-optical sum rules, the magnetic moment decreases with x, but remains fairly large for Fe2VAl, which might arise from its marginally magnetic nature.

Contrast effect in evaluating palatability of beverages.

This study aimed to clarify the contextual effect in evaluation of the pleasantness of beverages. Participants were presented a test stimulus and were then asked to rate how much they liked it before and after presentation of a contextual stimulus. Specifically, after participants were exposed to a less palatable beverage, they evaluated the test beverage as being more palatable than when their judgment of a test drink occurred after presentation of a neutral or palatable beverage (a positive contrast effect). This contextual effect can be explained by the reasoning that participants were affectively adapted to the palatability (less palatable) of a less palatable stimulus after repeated exposure; thus, they evaluated the test stimulus as more palatable. This study suggests that the evaluated value of the contextual stimuli affects evaluation of the test stimulus. The authors also suggest that these context effects are probably found in everyday life.

Attitudes to food and the role of food in life in the U.S.A., Japan, Flemish Belgium and France: possible implications for the diet-health debate.

For human beings, food is a critical contributor to physical well being, a major source of pleasure, worry and stress, a major occupant of waking time and, across the world, the single greatest category of expenditures. This is a first study of the way food functions in the minds and lives of people from four cultures. Adults and college students from Flemish Belgium, France, U.S.A. and Japan were surveyed with questions dealing with beliefs about the diet-health link, worry about food, the degree of consumption of foods modified to be "healthier" (e.g. reduced in salt or fat), the importance of food as a positive force in life, the tendency to associate foods with nutritional vs. culinary contexts, and satisfaction with the healthiness of one's own diet. In all domains except beliefs about the importance of diet for health, there are substantial country (and usually gender) differences. Generally, the group associating food most with health and least with pleasure is the Americans, and the group most food-pleasure-oriented and least food-health-oriented is the French. In all four countries, females, as opposed to males, show a pattern of attitudes that is more like the American pattern, and less like the French pattern. In either gender, French and Belgians tend to occupy the pleasure extreme, Americans the health extreme, with the Japanese in between. Ironically, the Americans, who do the most to alter their diet in the service of health, are the least likely to classify themselves as healthy eaters. We conclude that there are substantial cross-cultural differences in the extent to which food functions as a stressor vs. a pleasure. These differences may influence health and may partially account for national differences in rates of cardiovascular diseases (the "French paradox").

The CAD triad hypothesis: a mapping between three moral emotions (contempt, anger, disgust) and three moral codes (community, autonomy, divinity).

It is proposed that 3 emotions--contempt, anger, and disgust--are typically elicited, across cultures, by violations of 3 moral codes proposed by R. A. Shweder and his colleagues (R. A. Shweder, N. C. Much, M. Mahapatra, & L. Park, 1997). The proposed alignment links anger to autonomy (individual rights violations), contempt to community (violation of communal codes including hierarchy), and disgust to divinity (violations of purity-sanctity). This is the CAD triad hypothesis. Students in the United States and Japan were presented with descriptions of situations that involve 1 of the types of moral violations and asked to assign either an appropriate facial expression (from a set of 6) or an appropriate word (contempt, anger, disgust, or their translations). Results generally supported the CAD triad hypothesis. Results were further confirmed by analysis of facial expressions actually made by Americans to the descriptions of these situations.

Neutropenic colitis as a complication of high-dose chemotherapy for refractory testicular cancer.

A 44-year-old man received high-dose chemotherapy with carboplatin, etoposide and cyclophosphamide followed by autologous peripheral-blood stem-cell transplantation for treatment of refractory nonseminomatous testicular cancer (seminoma plus choriocarcinoma). The patient developed fever, watery diarrhea and abdominal pain at 10 days after the initiation of high-dose chemotherapy. Radiological examinations revealed adynamic ileus with thickened colon and small bowel wall and increasing ascites over the next 3 days. The patient subsequently suffered from disseminated intravascular coagulation, renal failure and hyperbilirubinemia despite systemic antibiotic therapy. Intensive medical care could barely avoid the fatal outcome. Neutropenic colitis has been recognized as a complication of acute leukemia or aplastic anemia. The present case indicates that this serious gastrointestinal complication can occur under profound neutropenic conditions induced by intensive chemotherapy for solid cancer.

[Inflammatory pseudotumor of the ureter: a case report].

A 57-year-old male was admitted because of the right flank pain. The image examinations, retrogradeurography, abdominal CT and MRI, showed a mass located at the upper right ureter. Although the tumor was not typical as ureteral cancer, we could not make a diagnosis of a benign tumor by image examinations. Therefore nephroureterectomy that was surgical method for ureteral cancer was performed. The tumor was diagnosed as inflammatory pseudotumor of the ureter by histological findings. Inflammatory pseudotumor is extremely rare for ulogeital organs. And this lesion is difficult to distinguish from malignancy only by image examinations. Therefore, the surgical resection and pathological studies are necessary.

Twin helical undulator beamline for soft X-ray spectroscopy at SPring-8.

A very high resolution soft X-ray beamline, BL25SU, has been designed and is under construction at SPring-8. Completely right or left circularly polarized light is supplied on a common axis of a newly designed twin helical undulator. A helicity modulation up to 10 Hz can be performed using five kicker magnets. The fundamental radiation covers the region 0.5-3 keV. Higher-order radiation is rather weak on the axis. A monochromator with varied-line-spacing plane gratings is installed to cover the region below 1.5 keV. A very high resolution beyond 10(4) is expected for the whole energy region.

[Pitfall in 201Tl-99mTc subtraction scintigraphy: a case of 99mTc-pertechnetate uptake in a parathyroid hyperplasia].

201Tl-99mTc subtraction scintigraphy has been recognized as a useful procedure in the preoperative localization of hyperfunctioning parathyroid glands. We experienced a case which showed 99mTc-pertechnetate uptake in a parathyroid hyperplasia. This case warned us to focus a lot of attention on the detection for preoperative localization. There has been no such case reported in the previous Japanese literatures. Hypervascularity and thick fibrous capsule presumed explanation for a rare case of marked pertechnetate uptake into a parathyroid hyperplasia.

Promoting effects and mechanisms of action of androgen in bladder carcinogenesis in male rats.

OBJECTIVE: It has been reported that blocking of testosterone production inhibits bladder carcinogenesis in various animal models. We investigated how testosterone acts on rat bladder carcinogenesis using an antiandrogen, flutamide, and a 5 alpha-reductase inhibitor, finasteride. METHODS: Experiment 1: we administered 0.05% BBN [N-butyl-N-(4-hydroxybutyl)nitrosamine] orally to 117 Wistar rats for 10 weeks, divided them into seven groups-control, surgical castration, finasteride (2 mg/kg), luteinizing hormone releasing hormone (LH-RH) agonist (1 mg/kg) flutamide (50 mg/kg), LH-RH agonist plus finasteride, and LH-RH agonist plus flutamide-, and then cystectomized them to investigate the incidence of bladder cancer on week 21; experiment 2: we administered 0.05% BBN to 154 Wistar rats for 7 weeks, divided them into seven groups-control, finasteride 2, 4, and 8 mg/kg, and flutamide 50, 100, and 200 mg/kg-, and then we cystectomized them to investigate the dose-dependent influence on bladder carcinogenesis of these drugs on week 20, and experiment 3: we investigated the presence of androgen receptors in rat and mouse normal bladder mucosa using a monoclonal antibody. RESULTS AND CONCLUSIONS: Experiment 1: Surgical castration and LH-RH agonist treatment significantly reduced the occurrence of carcinomas. There was no significant additive effect of coadministered finasteride or flutamide with LH-RH agonist. Finasteride or flutamide monotherapy showed no statistically significant effects on the results of experiment 1 at the doses used. Experiment 2: Flutamide showed a dose-dependent effect on reducing the number of rats with bladder cancer, and at a dosis of 200 mg/kg twice a week, the difference was statistically significant when compared with the control group, whereas finasteride had no statistically significant suppressing effect at any dose. Experiment 3: Mouse and rat bladder urothelium expressed the androgen receptor. Our results indicate that testosterone itself might have a more potent action on bladder carcinogenesis rather than its converting form, 5 alpha-dihydrotestosterone.

Evaluation of tapered-end toothbrushes regarding subgingival access efficacy.

The purpose of this in vitro study was to determine how two toothbrushes with highly tapered-end bristle designs compared to a conventional, slightly tapered toothbrush. Toothbrushing was carried out in the laboratory in order to evaluate the simulated subgingival efficacy of the three toothbrush designs. The performance of the three brushes was assessed by measuring the "subgingival regions" of gold-coated typodont left maxillary central teeth where the gold coating had been removed during brushing. The two toothbrushes with highly tapered bristles were statistically significantly (p < 0.01) more effective in removing the gold coating than the conventional toothbrush with slightly tapered bristles on the subgingival area on the anterior typodont teeth.