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Direct tension tests are indispensable for obtaining an accurate understanding of the deformation and failure characteristics of rocks in tension. For this technical note, the authors collected original papers published in international journals and surveyed the previously reported methods and results of direct tension tests on rocks. Some important factors affecting the strength and stress–strain curve are discussed, such as the shape, size, anisotropy, and water content of the specimen; the loading rate; and the confining pressure. The relationship between the results of the direct tension tests and those of other tests also is discussed. Although various types of testing apparatuses have been adopted in direct tension tests on rocks, the dependence of test results on the apparatuses has not been investigated. In this study, direct tension tests were conducted using various testing apparatuses in seven laboratories. The results of the direct tension tests showed that direct tensile strengths were not dependent on the type of test apparatus used or whether a flexible linkage system was used. The results of the tuff in this study showed that the coefficient of variation of the direct tensile strengths is smaller than that of the Brazilian tensile strengths. Moreover, the results revealed that the coefficient of variation of the direct tensile strengths is comparable to that of the uniaxial compressive strengths of the tuff. The authors noted that to obtain the stress–strain curve from the pre-failure region to the post-failure region, it is necessary to conduct a test with a high-stiffness machine and without a flexible linkage system. This technical note summarized the results of the standardization activity by the authors in the Japanese Geotechnical Society.

This work aims at understanding the formation and stability of a layered structure of brucite mineral [Mg(OH)2] via density functional calculations. Because Mg−O−Mg bond formation from a hydrolyzed species of Mg(II) ion is a critical elemental step of mineralization, we studied the reaction mechanism of Mg−O−Mg linkage using a model cluster, [Mg(OH)2]n (n = 1−10), in the gas phase and a water solution. The results indicate that no barrier exists during the reaction path from [Mg(OH)2]n-1 + Mg(OH)2 to [Mg(OH)2]n with no significant solvent effect of water. It has been confirmed that this polymerization reaction leads spontaneously to a planar cluster, which is regarded as a part of the brucite layer. The results suggest that the layered structure of brucite is a natural consequence of polymerization. These findings will be utilized to establish microscopic modeling for studying a templating effect on the formation of an inorganic thin film.

We have developed a novel method of modifying a solid surface with a single-layered film of anionic phyllosilicate as an anchor of cationic functional molecules. According to the method, a hybrid film of octadecylammonium and montmorillonite layer was deposited onto a Si substrate by the Langmuir−Blodgett method. Thereafter the Si substrate was immersed in methanol to remove an organic layer, leaving a single-layered montmorillonite film. As a final step, a cationic chiral molecule, Δ-[Ru(phen)3]²⁺ (phen = 1,10-phenanthroline), was self-assembled from its aqueous solution onto the single-layered montmorillonite film. The thickness of a single-layered montmorillonite film was estimated to be ca. 1.5−1.6 nm by atomic force microscopy observation. The thickness of the film increased to ca. 2.6−2.7 nm after the self-assembly treatment. The results were consistent with the analyses of interference oscillation patterns of specular X-ray reflectivity (SXR) curves. From the analyses of SXR curves, the thickness of the adlayer of Δ-[Ru(phen)3]²⁺ was estimated to be ca. 1.5−1.6 nm. On the basis of this, it was concluded that Δ-[Ru(phen)3]²⁺ formed an adlayer within a monolayer scale. The present method may open a way to modify a solid surface by use of a water-soluble functional molecule with neither cross-linking group nor amphiphilic property.

BACKGROUND: Non-selective cyclooxygenase (COX) inhibitors (non-steroidal anti-inflammatory drugs) inhibit large bowel carcinogenesis in patients with familial adenomatous polyposis (FAP). Their role in the duodenum of these patients is less certain. The disease modifying activity of specific COX-2 inhibitors has not been explored in humans. Patients and methods: This was a randomised, double blind, placebo controlled study of celecoxib (100 mg twice daily (n=34) or 400 mg twice daily (n=32)) versus placebo (n=17), given orally twice daily for six months to patients with FAP. Efficacy was assessed qualitatively by blinded review of shuffled endoscopy videotapes comparing the extent of duodenal polyposis at entry and at six months and quantitatively by measurement of the percentage change in duodenal area covered by discrete and plaque-like adenomas from photographs of high and low density polyposis. RESULTS: Shuffled and blinded video review showed a statistically significant effect of 400 mg twice daily celecoxib compared with placebo treatment (p=0.033) with all five independent observers scoring a beneficial effect. Overall, patients taking celecoxib 400 mg twice daily showed a 14.5% reduction in involved areas compared with a 1.4% for placebo (p=0.436). However, patients with clinically significant disease at baseline (greater than 5% covered by polyps) showed a 31% reduction in involved areas with celecoxib 400 mg twice daily compared with 8% on placebo (p=0.049). CONCLUSIONS: A panel of five endoscopists found a significant reduction in duodenal polyposis after six months of treatment with celecoxib 400 mg twice daily. COX-2 inhibition may help this otherwise untreatable condition.

Structure-activity relationship (SAR) observations were made for theZ-type European corn borer moth pheromone, (Z)-11-tetradecen-1-ol acetate, and a series of analogs with fluorination in the alcohol portion of the molecule. The attractiveness of these analogs and the pheromone was compared to the electrostatic potential map of the molecular mechanics (MM) minimized lowest energy conformation for each compound. A critical range of electrostatic potential on the protons of the double-bond appears to be essential for optimal acceptor fit and attractiveness.

Conventionally a processing program for NC (numerical control) machine is coded by a skilled operator or programmer, who has the excellent experience of machine work. As compared with the processing time taken by NC machine, the programming time is extremely long even the skilled programmer does it. According to our supporting system, a processing program is automatically generated from the output of CAD (computer aided design) system. The prototype of our supporting system is applied to the NC turret punch press machine, wherein the shape, size of the holes to be punched out and the order of the processings are indicated by the program. Usually the skilled programmer knows which tools installed in the turret of the machine should be used and how the order of the processings should be determined. The present system contains such information in the knowledgebase and uses it to generate the processing program. The knowledge in the knowledgebase consists of two kinds of the informations. The prototype system developed generates a processing program much faster than a skilled programmer. The result shows that the practical model can be developed by increasing the amount of knowledges.

Transcription factor Nrf2 is essential for the antioxidant responsive element (ARE)-mediated induction of phase II detoxifying and oxidative stress enzyme genes. Detailed analysis of differential Nrf2 activity displayed in transfected cell lines ultimately led to the identification of a new protein, which we named Keap1, that suppresses Nrf2 transcriptional activity by specific binding to its evolutionarily conserved amino-terminal regulatory domain. The closest homolog of Keap1 is a Drosophila actin-binding protein called Kelch, implying that Keap1 might be a Nrf2 cytoplasmic effector. We then showed that electrophilic agents antagonize Keap1 inhibition of Nrf2 activity in vivo, allowing Nrf2 to traverse from the cytoplasm to the nucleus and potentiate the ARE response. We postulate that Keap1 and Nrf2 constitute a crucial cellular sensor for oxidative stress, and together mediate a key step in the signaling pathway that leads to transcriptional activation by this novel Nrf2 nuclear shuttling mechanism. The activation of Nrf2 leads in turn to the induction of phase II enzyme and antioxidative stress genes in response to electrophiles and reactive oxygen species.

Inelastic neutron spectra of acetamide-h5 and acetamide-h2 have been measured at different temperatures below 40K and with high energy resolution in the energy range up to 15 meV. A lattice dynamical model on the basis of atom-atom potentials and electric charges obtained from first principles calculations describes the spectra well if soft internal molecular modes are included. The model is used to reproduce the temperature dependence of the tunnelling transition of the methyl group. For this purpose the density of states is split into that of an isolated rotor in a static field and that of the phonon bath. The effects of the rotor-phonon coupling are evaluated in second order perturbation theory. The broadening of tunnelling lines comes out correctly when the atom atom potentials taken from literature are scaled down by 20%. To get the shift right the strength of the coupling to the lattice needed to be different for the A type symmetry state from that for the E type state. The coupling with the low frequency phonons appears to be very weak.

The lattice dynamics of layered compounds is discussed on the basis of a set of two-dimensional lattices perturbed by weak interlayer interactions. Experimental observations which indicate quasi-two-dimensional character such as the temperature dependence of Debye temperatures and the Kohn anomalies are emphasized. Si discute sulla base di un insieme di reticoli bidimensionali perturbati da interazioni deboli fra strati la dinamica reticolare di composti stratificati. Si pone l’accento sulle osservazioni sperimentali che indicano un carattere quasi bidimensionale come la dipendenza delle temperature di Debye dalla temperatura e le anomalie di Kohn. Обсуждается динамика решетки слоистых соединений на основе системы двухмерных решеток, возмущенных слабыми взаимодействиями между слоями. Особое значение придается экспериментальным наблюдениям, которые указывают на квази-двухмерный характер температурной зависимости дебаевских температур и аномалий Кона.

Statement of problem . Superplastic forming of Ti-6Al-4V alloy has been used in the fabrication of a removable denture framework. The method provides the titanium alloy denture framework with excellent physical properties not seen in cast titanium prostheses. Purpose . This study describes the technical procedure for fabricating removable dentures with this type of framework and evaluates clinical applications of the dentures in short-term follow-up periods from 6 months to 3 years. Results . Results of this study demonstrated that the dentures functioned well and did not cause any major clinical difficulties. The patients have expressed satisfaction with the dentures at regular recall appointments. Conclusion . The clinical observations suggest that this method is suitable for fabricating titanium alloy removable dentures. (J Prosthet Dent 1997;77:583-7.)

A human-mouse hybridoma has been produced by fusion of Hashimoto thyroid lymphocytes with the mouse myeloma line X63-Ag8.653. The cloned hybridoma secreted 2.5 µg per 106 cells per day of an IgG kappa thyroid peroxidase (TPO) autoantibody (2G4) with high affinity (2.5×109 molar-1) and specificity for human TPO. 2G4 did not react with lactoperoxidase, horseradish peroxidase or human myeloperoxidase or with porcine TPO or with human thyroglobulin. Plastic tubes coated with 2G4 bound about 50% of 125I-labelled human TPO added and the binding was inhibited by IgGs prepared from 18/18 TPO autoantibody-positive sera. This indicated that all 18 sera contained autoantibodies which recognised the same (or closely related) epitope as 2' 34. Plastic tubes coated with IgGs from different TPO autoantibody-positive patient sera also bound 125I-labelled TPO but inhibition by 2G4 in this system was not complete. This suggested that the sera contained at least 2 types of TPO autoantibodies. with only one type of autoantibody reactive with the same epitope as 2G4.

The electrical conductivities of the copper (I) halide-sulphonium halide systems were measured and high conductivity copper ion conductors were found in the copper (I) iodide-1-methyl-1-thioniacyclohexane iodide (C5H10SCH3I) and copper (I) iodide-4-methyl-1, 4-oxathianium iodide (C4H8OSCH3I) systems. The dependence of electrical conductivity on the composition showed that the maximum conductivity appeared at 83.4 mol% CuI for these two systems. The highest conductivities of the systems, CuI-C5H10SCH3I and CuI-C4H8OSCH3I, were 1.4×10-3 and 7.2×10-4 (O cm)-1 at 25‡ C, respectively. The conduction in these systems was essentially ionic.

Abstract: A 1 Ci Pu−Be neutron source and a low-background beta-spectrometer were used to activate and to measure the beta-rays of low-activity. The main characteristics of this method can be given as follow: The determined S/N ratio increases because the background beta-rays are lower than the gamma-rays. For example, the sensitivity obtained for quantitative analysis of sulphur in silicon is 100 ppm in case of S/N=1.0.

Extensive measurements of the phonon dispersion curves of trigonal mercury have been carried out by neutron inelastic scattering. Some transverse branches of the phonon spectrum have very low frequencies, as small as 0.9 meV at the zone boundary, compared with a maximum lattice frequency of 15 meV. The data have been accurately fitted with an 8-neighbor Born-von Kármán model, and a reliable phonon density of states F(ω) has been calculated. Comparison with α2(ω)F(ω) derived from tunneling measurements reveals a substantial increase in α2(ω) at low frequencies. Direct calculation of α2(ω)F(ω) from the BvK model, assuming a simple form for the electron-phonon matrix element, gives λ = 2.0 compared with λ = 1.6 from tunneling. We discuss the origin of the frequency dependence of α2 (ω).

We have devised a funnel-shaped transparent cap for the endoscopic diagnosis and treatment of stenosis in the digestive tract. This funnel-shaped cap is made of highly transparent methacrylic resin. A 73-year-old woman with reflux esophagitis (categorized as grade D by the Los Angeles Classification) visited our hospital with the chief complaint of dysphagia. She was examined using an endoscope equipped with a transparent vinyl chloride hood at its tip. Many pieces of food were found to be trapped in the esophagus. These were removed using tripod forceps or aspirated into the hood. The internal diameter of the stenotic segment was as small as 1 or 2 mm, and it was difficult to advance the endoscope past the stenosis. The endoscope was withdrawn, and the attached hood was removed and replaced with a transparent cap. This provided clear visualization of the mucosal surface of the stenotic segment, which could not be examined using any conventional device, permitting the stenosis to be relieved.

A nine-component synthetic mixture was developed to replace protein hydrolysates as food bait for melon flies, Dacus cucurbitae Coquillett, based on likely breakdown products of protein fermentation and on nutritional considerations. The nine-component mixture was found to be as attractive as a standard hydrolyzed protein bait. Subsequent research showed that only four of the nine components were important. The four-component mixture, made up of ammonium bicarbonate, linolenic acid, putrescine, and pyrrolidine, was as effective as the standard food bait.

Aryl esters of citronellylcarbamic and a few related acids were prepared and tested for juvenile hormone activity against the yellow mealworm, Tenebrio molitor L., and the large milkweed bug, Oncopeltus fasciatus (Dallas). Most of these compounds, especially the phenyl, p-toly1, 3,4-(methylenedioxy) phenyl, and o-chlorophenyl esters, were active against T. molitors; their activity against O. fasciatus was generally much lower.

We recently reported (Braun et al. 1968) 2 convenient synthetic pathways leading to methyl 10,11-epoxy-7-ethyl- 3,11-dimethyl-2,6-tridecadienoate (I) (see Fig. 1), the insect juvenile hormone isolated by Röller et al. (1967) from adult male cecropia moths, Hyalophora cecropia (L.), and later identified by the same group (Dahm et al. 1967). Even though compound I, I-a, when it is prepared by our methods, is presumably a mixture of all 16 possible isomers, it displayed very high juvenile hormone activity when it was assayed with pupae of the yellow mealworm, Tenebrio molitor L., by the method of Bowers and Thompson (1963). Compound I-a was about ⅓ as active as the natural juvenile hormone (Röller et al. 1965) and twice as active as methyl 10,11-epoxy-3,7,11-trimethyl-2,6- dodecadienoate (II) (Bowers et al. 1965), one of the most active synthetic compounds to date. Subsequent preparation of additional quantities of I by reaction scheme B outlined in our earlier publication (Braun et al. 1968) and the more convenient epoxidation procedure using m-chloroperbenzoic acid led to a product (I-b) with activity about ⅓ that of our product (I-a), which was prepared using the epoxidation method of van Tamelen and Sharpless (1967). This loss of activity is not surprising, since peracid epoxidation is known to be much less selective (leading to a mixture of 10,11 and 6,7 epoxides) than the van Tamelen procedure, which yields terminal epoxides almost exclusively.

Squalene 2,3-oxide has been established as an intermediate in the conversion of squalene (an acyclic triterpene) into the familiar polycyclic systems, lanosterol and cholesterol (Godtfredsen et al. 1968, and references cited therein). The suggestion has been made that squalene 2,3-epoxide may have a general role in nature as the immediate acyclic precursor of polycyclic triterpenes having a 3ß-hydroxy group.