Structure of intercalated Cs in zeolite ITQ-4: an array of metal ions and correlated electrons confined in a pseudo-1D nanoporous host.

The presence of Cs+ ions in the pseudo-1D nanopores of zeolite ITQ-4, Si32O64, is confirmed by x-ray diffraction and atomic pair distribution function analysis. Inside the nanopores the Cs+ ions are found to assemble in zigzag chains and thus form an extended, positively charged sublattice providing charge balance for a low-density electron gas also confined to the nanopores.

Investigation and analysis of a reported incident resulting in an actual airline hijacking due to a fanatical and engrossed VR state.

We begin this report by defining Chronic Alternate-World Disorder (CAWD) as a symptomatic behavior in which a person becomes fanatically engrossed in a virtual-reality (VR) world to the extent that he or she can no longer distinguish between the actual world and virtual reality. We then report on our investigation and provide an analysis and discussion of what we believe to be a case of CAWD. The case in question involves a perpetrator who hijacked a jumbo jetliner in order to fly the airplane on his own, after developing CAWD from the use of light-simulator software. Psychiatrists and physicians specializing in VR-related disorders have analyzed the case's psychological, social, and technical background based on previously disclosed information. We believe symptomatic cases of CAWD will increase as VR spreads throughout our society. In view of this, our objective is to propose precautionary and preventive measures for providers of VR systems for patients with schizophrenia or personality disorders, from psychiatric and sociological perspectives.

Clinical effect of canal plugging on paroxysmal positional vertigo.

A 63-year-old woman had disabling positional vertigo for four months. She showed intense direction-changing apogeotropic nystagmus. Conservative treatment failed to resolve her vertigo. From the findings of the nystagmus, cupulolithiasis of the right lateral canal was suspected. Plugging of this canal successfully eliminated the nystagmus and positional vertigo. Positional vertigo can sometimes be disabling and unresponsive to conservative therapy. Careful analysis of the nystagmus may allow selection of the most appropriate treatment.

Supramolecular complex of cytochrome c with lariat ether: solubilization, redox behavior and catalytic activity of cytochrome c in methanol.

A variety of lariat ethers were employed to solubilize water-soluble cytochrome c in methanol, in which alcohol, ether, ester, amine, and amide functionalities were attached as cation-ligating side arms to 18-crown-6, 15-crown-5, and 12-crown-4 rings. Among these lariat ethers, the alcohol-armed 18-crown-6 derivative offered the highest solubilization efficiency for cytochrome c via supramolecular complexation. The resulting cytochrome c-lariat ether complexes were electrochemically and spectroscopically characterized and confirmed to have redox-active heme structures of 6-coordinate low-spin population in methanol. Some of them catalyzed the oxidation of pinacyanol chloride with hydrogen peroxide in methanol and exhibited higher activities than unmodified cytochrome c and its poly(ethylene glycolated) derivative. Since the supramolecular complexation between lariat ether and cytochrome c includes extremely simple procedures, it provides a facile preparation method of effective biocatalysts working in organic solvents from metalloproteins.

Clinical features of paroxysmal positional vertigo presenting combined lesions.

Benign paroxysmal positional vertigo (BPPV) is one of the common vestibular disorders. Canalolithiasis is thought to be a likely lesion. A canalith repositioning procedure (CRP by Epley) generally yields good resolution of vertigo and nystagmus. The authors confirmed the efficacy of this procedure on typical BPPV of the posterior semicircular canal type. We designed a new procedure for BPPV of the lateral canal type, which also yielded satisfactory results. BPPV sometimes presents a nystagmus pattern, which suggests multiple lesions. We have seen eight cases of BPPV showing nystagmus that combines both the posterior and the lateral canal types. Combined CRP was performed on these cases, which again gave good clinical results. Other BPPV cases were associated with central lesions. We must be aware that BPPV may involve multiple canals and may be associated with central lesions.

The interactive surrogate travel system.

The Interactive Surrogate Travel (IST) system is based on the super-miniaturized system of virtual technology, Cave Automatic Virtual Environment (CAVE). Using bilateral virtual reality (VR-to-VR) communications, IST enables the testing of subjects via interactive communications. It appears that IST will find practical applications in the near future. We examined the utility of IST in medical treatment and psychiatric tests. Psychiatric symptoms reflect human pathos, which in turn are greatly influenced by culture. If these culture-bound symptoms can be adequately communicated between providers and clients of different cultures, we can develop effective telepsychiatric services across different societies and cultures. IST requires high-speed transmission and gigabyte circuits. A pilot project tested the utility of IST (through the use of optical fiber communications on earth) as a basis for experiments via the Gigabit satellite, to be launched in the year 2002.

The new-concept full-face-type helmet with removable cheek pads.

BACKGROUND: The American College of Surgeons proposed a method of removing helmets. But the problem with full-face-type helmets is that their shape makes them difficult to remove. METHODS: A dummy doll was fixed to a smooth bed surface in the supine position, and a full-face-type helmet with a hook attached to the vertex was placed on the doll's head. A spring balance was attached to the hook, traction was applied to the helmet through the spring balance, and the maximum tension needed to completely remove the helmet was measured. RESULTS: A tension of 13.2 +/- 1.8 kg was found. But when cheek pads were removed, the tension required to remove the helmet was 1.7 +/- 0.2 kg. CONCLUSION: We devised a full-face-type helmet that uses removable cheek pads so that helmet removal can be performed safely by removing only the cheek pads in the event of an accident.

Effects of levofolinate calcium on subacute intravenous toxicity of 5-fluorouracil in rats.

To clarify whether levofolinate calcium (1-LV) enhances 5-fluorouracil (5-FU) toxicity, a 4-week toxicity study of 5-FU (10 mg/kg/day) in combination with 1-LV (6, 20 or 60 mg/kg/day) was conducted in rats. In the 5-FU alone group, a decrease in body weight gain, food consumption, RBC parameter and WBC counts were detected. Histopathologically, lymphoid depletion of lymphatic organs, hematopoiesis enhancement of the spleen and myelosuppression were observed. In the group for which 5-FU was combined with 1-LV, the RBC counts decreased, extramedullary hematopoiesis increased and the suppression of lymphatic organs was enhanced. Changes in the lymphatic organs were observed at 20 mg/kg/day of 1-LV and above. In monitoring of blood drug concentrations of 1-LV, 5-methyl tetrahydrofolic acid, a metabolite of 1-LV, and 5-FU after the 1st and 14th dosings, there was no apparent difference between 5-FU alone and 5-FU combined with 1-LV in Cmax and AUC0-infinity. The potentiation induced by 1-LV in the toxicity of 5-FU appeared to be mainly immuno-suppression and myelosuppression, which were related to the anti-tumor activity of 5-FU. Plasma concentrations of 5-FU and 1-LV in this study overwhelmed the concentrations that enhancement of thymidylate synthetase (TS) inhibition due to 5-FU was observed by addition of 1-LV in vitro. Therefore toxic potentiation of 5-FU due to simultaneous 1-LV dosing is presumed to be concerned with an increased ternary complex (FdUMP-TS-5,10-methylenetetrahydrofolate) formation and a greater extent of TS inhibition.

Correlations in one-dimensional fully developed chaos.

Correlations in the baker map and the tent map as examples of one-dimensional, fully developed chaos are considered. It is shown, utilizing symbolic dynamical systems derived from these maps, that the vanishing second-order correlation function is not sufficient to guarantee uncorrelatedness. Importance of the higher-order, especially third-order, correlation functions is emphasized for chaotic systems. In search of the quantities that grasp correlational behaviors as a whole in chaotic systems, it is proposed to use the fixed-separation correlation integral, which is a modified quantity of the usual correlation integral devised to calculate the fractal dimension of strange attractors, for these maps. It is shown that the new quantity contains all the even-number orders of autocorrelation function that are commonly considered.

Purification and characterization of two distinct dipeptidyl aminopeptidases in soluble fraction from monkey brain and their action on enkephalins.

Two distinct dipeptidyl aminopeptidases, which were designated DPP-A and DPP-B, were purified from soluble fraction of monkey brain using Leu-enkephalin as the substrate. The enzymes were purified 187 and 136 fold, respectively. Both enzymes showed the optimum pH in neutral range. Their molecular weights were almost equal and were estimated to be about 100,000. Their Km values with Leu-enkephalin as the substrate were 5.6 X 10(-5) and 1.1 X 10(-5) M, respectively. Among synthesized substrates, the highest affinity of the enzymes was toward arginyl-arginine beta-naphthylamide with the Km values of 6.25 X 10(-5) and 6.41 X 10(-5) M, respectively. Both enzyme activities were inhibited by the metal-chelators DFP and PCMB. Two hundred fifty microM arphamenine A inhibited DPP-A and -B with inhibition of 36.6% and 44.1%, respectively. Beta-endorphin, ACTH, and glucagon inhibited only DPP-B, while beta-lipotropin and angiotensin II inhibited both DPP-A and -B when Leu-enkephalin was used as the substrate.