Catechol - an Oviposition Stimulant for Cigarette Beetle in Roasted Coffee Beans

The cigarette beetle, Lasioderma serricorne, is a serious global pest that preys on stored food products. Larvae of the beetle cannot grow on roasted coffee beans or dried black or green tea leaves, although they oviposit on such products. We investigated oviposition by the beetles on MeOH extracts of the above products. The number of eggs laid increased with an increase in dose of each extract, indicating that chemical factors stimulate oviposition by the beetles. This was especially true for \ coffee bean extracts, which elicited high numbers of eggs even at a low dose (0.1 g bean equivalent/ml) compared to other extracts. Coffee beans were extracted in hexane, chloroform, 1-butanol, MeOH, and 20 % MeOH in water. The number of eggs laid was higher on filter papers treated with chloroform, 1-butanol, MeOH, and 20 % MeOH in water extracts than on control (solvent alone) papers. The chloroform extract was fractionated by silica-gel column chromatography. Nine compounds were identified by gas chromatography/mass spectrometry from an active fraction. Of these compounds, only a significant ovipositional response to catechol was observed.     

Antinociceptive effects of ONO-9902, an enkephalinase inhibitor, after visceral stress condition in rats

PURPOSE: The present study was designed to examine the antinociceptive effects of orally administered ONO-9902, an enkephalinase inhibitor, on both somatic and visceral pain after visceral stress conditions. METHODS: Twenty six male rats were examined. Tail-flick (TF) and colorectal distension (CD) tests were used to determine somatic and visceral antinociceptive effects, respectively. Measurements were performed in rats under immediate post-stress conditions (group ST; n = 14) and in rats nor under stress conditions (group NST; n = 12). In the stressed group, the same device, CD, for visceral antinociceptive effects was used for visceral stress and was applied with an intracolonic pressure of 60 mmHg for 20 min after drug administration. The TF latency and CD threshold were measured before and at 30, 40, 50, 60 and 90 min after administration of ONO-9902 300 mg.kg-1 or distilled water. RESULTS: Orally administered ONO-9902 did not produce any changes in the % maximum possible effect (%MPE) in either TF or CD tests in the unstressed group. In the stressed group, %MPE in the CD test increased 18% and 31% at 30 and 40 min, respectively, after oral administration of ONO-9902 compared with the control group (P < 0.05). However, %MPE to TF test did not alter even after the CD-induced stress condition. CONCLUSION: These results suggest that ONO-9902 may have analgesic effects on visceral pain but not on somatic pain under immediate post-stress conditions.     

Effect of interferon-gamma on nitric oxide hemoglobin production in endotoxin-treated rats and its synergism with interleukin 1 or tumor necrosis factor

We studied the in vivo effect of interferon-gamma (IFN-gamma) on nitric oxide (NO) generation. ESR spectra of nitric oxide hemoglobin (HbNO) appeared after a lag time of 2h in the blood of rats treated with Escherichia coli lipopolysaccharide (LPS). IFN-gamma enhanced LPS-induced HbNO formation in rats without modifying the time lag, although IFN-gamma alone did not induce HbNO formation. The plasma nitrate concentration was approximately one order of magnitude higher than the HbNO concentration. On treatment with LPS alone, the amount of tumor necrosis factor (TNF) released decreased after 2 h. Simultaneous addition of IFN-gamma and LPS increased TNF release for at least 8 h. Interleukin 1 (IL-1) release was detected only at 2 h in both groups. We also investigated the in vivo interactions of these cytokines. TNF plus IL-1 induced the greatest HbNO generation, followed by TNF plus IFN-gamma, and then IL-1 plus IFN-gamma. These results suggest that increase of TNF release by IFN-gamma plays a key role in NO generation in LPS-treated rats.     

Sensorless control of SRM using magnetizing curves

Among various variable speed drives, switched reluctance motors (SRMs) have been found to be competitive with traditional ac and dc motors because of their simple construction and drive electronics. However, the necessity of using a shaft‐mounted position sensor is one of the drawbacks of the SRM from the standpoint of cost, size, and reliability. Position sensorless SRM drives are expected to solve these problems. This paper presents a method of position sensorless control based on a simple fuzzy model of nonlinear position‐dependent magnetizing curves. The sensors needed for the drive are one voltage sensor and one current sensor. Experimental studies using a 1.5‐kW, 5400‐rpm SRM with a 6/4 tooth configuration show that the maximum error of rotor position estimation is less than three mechanical degrees in the 1:20 speed range under any load conditions. © 2001 Scripta Technica, Electr Eng Jpn, 135(2): 60–68, 2001     

Dislocation and point-force-based approach to the special Green's Function BEM for elliptic hole and crack problems in two dimensions

In this paper we give the theoretical foundation for a dislocation and point-force-based approach to the special Green's function boundary element method and formulate, as an example, the special Green's function boundary element method for elliptic hole and crack problems. The crack is treated as a particular case of the elliptic hole. We adopt a physical interpretation of Somigliana's identity and formulate the boundary element method in terms of distributions of point forces and dislocation dipoles in the infinite domain with an elliptic hole. There is no need to model the hole by the boundary elements since the traction free boundary condition there for the point force and the dislocation dipole is automatically satisfied. The Green's functions are derived following the Muskhelishvili complex variable formalism and the boundary element method is formulated using complex variables. All the boundary integrals, including the formula for the stress intensity factor for the crack, are evaluated analytically to give a simple yet accurate special Green's function boundary element method. The numerical results obtained for the stress concentration and intensity factors are extremely accurate. © 1997 John Wiley & Sons, Ltd.     

Experience of superheater tubes in municipal waste incineration plant

Two years after the start of operations at the Tokachi Association for Municipal Waste Disposal and Treatment Services municipal waste incineration plant (name: Kuririn Center), which generates 400°C steam, an investigation of the plant's superheater tubes was conducted. The investigation consisted primarily of analyzing ash deposits, measuring tube wall thickness loss and observing tube sections after removal. The concentration of Cl in the deposited ash was found to increase as the temperature of the gas rose, and the amount of deposited ash tended to increase as the temperature of the gas rose. Tube damage consisted primarily of a uniform loss in thickness. Intergranular corrosion and other local corrosion was not observed. The results of thickness‐loss measurements showed that, after approximately two years in operation, tubes (SUS310) lost a maximum of 0.45 mm in thickness due to high‐temperature corrosion in locations where the steam temperature reached 400°C. Superheater tubes were also apparently damaged from the effects of a soot blower, resulting in an observed maximum loss of 0.9 mm thickness after approximately two years. Furthermore, the rate of thickness loss tended to increase after one year had passed.     

Radially and azimuthally dependent resonance self-shielding treatment for general multi-region geometry based on a unified theory

A unified resonance self-shielding method, which can treat general sub-divided fuel regions, is developed for lattice physics calculations in reactor physics field. In a past study, a hybrid resonance treatment has been developed by theoretically integrating equivalence theory and ultra-fine-group slowing-down calculation. It can be applied to a wide range of neutron spectrum conditions including low moderator density ranges in severe accident states, as long as each fuel region is not sub-divided. In order to extend the method for radially and azimuthally sub-divided multi-region geometry, a new resonance treatment is established by incorporating the essence of sub-group method. The present method is composed of two-step flux calculation, i.e. ‘coarse geometry + fine energy’ (first step) and ‘fine geometry + coarse energy’ (second step) calculations. The first step corresponds to a hybrid model of the equivalence theory and the ultra-fine-group calculation, and the second step corresponds to the sub-group method. From the verification results, effective cross-sections by the new method show good agreement with the continuous energy Monte-Carlo results for various multi-region geometries including non-uniform fuel compositions and temperature distributions. The present method can accurately generate effective cross-sections with short computation time in general lattice physics calculations.     

Pixels consisting of a single vertical-cavity laser thyristor and adouble vertical-cavity phototransistor

Bidirectionally cascadable optical pixels that consist of a single-vertical-cavity surface-emitting laser (VCSEL) thyristor and a double-vertical-cavity phototransistor are proposed. Despite almost identical layer structures, each device characteristic can be independently optimized by introducing a λ/2-spacer layer into the phototransistor section. A lasing threshold of 0.8 mA and a slope efficiency of 0.25 W/A are obtained for the laser thyristor, and a flat-topped photocurrent spectrum over 30 A and a photocurrent gain of 70 A/W are obtained for the phototransistor at the resonant wavelength. This work demonstrates the possibility of monolithic integration using thermal desorption and a regrowth technique and the suitability of these devices for massively parallel optical interconnections     

Ferrimagnetic Particles in the Lung Part 1: The Magnetizing Process

The magnetization process of ferrimagnetic particles in the lung takes place when an external magnetic field is applied to the lung; the particles both become magnetized and rotate toward alignment with the applied field. The purpose here is to consolidate previous and new measurements of this process, for Fe3O4 particles in the human lung, and to interpret the measurements. The particular quantity measured was Bn, the remanent magnetic field at the chest produced by the particles after removal of the applied field. Bn was measured as a function of three variables. The first two are the strength and duration of the applied field, yielding the remanent magnetization curve and the viscosity curve respectively; these were measured both for particles initially unmagnetized and initialiy magnetized. The curves are qualitatively explained by a simple physics model consisting of single-domain and multidomain particles; these reside in a viscous fluid and experience physiological impulses (relaxation) which oppose the alignment during magnetization. The third variable is the state of breathing; Bn was measured when normal breathing was switched to exhale-and-hold during either magnetization or measurement. The effects on Bn of this switch are explained by considering the alveolar walls; forced exhalation is assumed to "crumple" the walls, thereby realigning the particles contained in the alveoli.     

Thin CdS films prepared by metalorganic chemical vapor deposition

Polycrystalline CdS thin films have been deposited on borosilicate glass substrates coated with ITO film by metalorganic chemical vapor deposition using dimethyl cadmium and diethyl sulfide as source materials. The growth of CdS film occurred at substrate temperatures within the range of 280–360°C. The deposition rate increased with increasing VI/II molar ratio at any substrate temperature and showed a maximum value at the VI/II molar ratio of 4. The grain size of as-deposited CdS film prepared at substrate temperatures from 300°C to 360°C was about 0.1 μm. The CdS films consist of hexagonal form with a preferential orientation of the (0 0 2) plane parallel to the substrate. Thin CdS film with high optical transmittance was prepared at 350°C with the VI/II molar ratio of 4. The CdS film deposited by MOCVD may be used as a window layer for CdS/CdTe solar cell.