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1.
The significance of the alkyl group at the C-4 of (+)-trans-verbenyl acetate, which is the sex pheromone mimic of the American cockroach, was investigated. Seven alcohols possessing an ethyl, propyl, or dimethyl group at this position of the 6,6-dimethylbicyclo[3.1.1]heptane skeleton were synthesized and evaluated by behavioral assay. All of the alcohols were inactive, while three of four acetates of the 2-alcohols induced sexual behavior in male cockroaches at the 0.02 or 0.5 mg dosage level, either of which is many orders of magnitude higher than the threshold level of the natural sex pheromones (10–8 mg). Among the acetates, the compounds with a methyl group or an -oriented ethyl group at C-4 showed the highest activity. The results are discussed in terms of spatial requirements of the molecules for interactions with the receptor.Studies on the sex pheromone mimic of the American cockroach, (+)-trans-verbenyl acetate. Part VIII. For Part VII, seeComp. Biochem. Physiol.,70A: 229–234 (1981).  相似文献   
2.
In recent years drastic shifts in the paradigms of politics, economics and technologies have occurred throughout the world. The shifts in these three fields are all related. It is our responsibility to investigate these shifts from the aspects of society and mankind for the prosperity of future generations. For this, societies should share with each other their wisdom and knowledge in an effort to plan for the future.Presented at conference on Ecology of Science and Technology, Japan Science Foundation, Tokyo, 1992.  相似文献   
3.
以载重子午线轮胎胎面胶为例,应用发泡点分析仪(BPA)测试和计算胶料温度不饱和度及扩散系数,探讨BPA的测试原理和方法。结果表明,热扩散系数与热源温度无关,而与加热时间和厚度相关。应用BPA对胶料进行硫化分析,有助于硫化工艺设计和生产控制。  相似文献   
4.
This paper discusses tree inception and breakdown voltage characteristics of XLPE cable insulation subjected to impulse voltages superimposed on ac voltage. The tree initiation tests were performed on laboratory-molded specimens equipped with needle electrodes, whereas the breakdown tests were conducted on a full-sized cable. The impulse tree initiation stress was found to be dependent on the magnitude of the pre-applied ac stress and the relative polarities of the impulse and the ac peak at the instant of their superposition. Although the impulse polarity has an effect on the tree inception, the general behavior is that the tree inception stress always decreases with an increase of the pre-applied ac stress. This phenomenon is discussed in terms of the space charge effect and the influence of the impulse voltage application itself. The impulse strength of a full-sized cable insulation was found to be independent of the pre-applied ac stress as long as that stress did not exceed the operating stress of a 500 kV cable insulation. However, subjecting cable insulation to higher ac stresses before impulse application caused a reduction of its breakdown strength as compared with the insulation without ac prestressing  相似文献   
5.
In order to study the effect of surface acidity of activated carbons on their adsorption characteristics, three kinds of aromatic amines and four kinds of o-substituted phenols were adsorbed from organic solutions by twelve kinds of activated carbons of different acidity and of known pore-structure. It was demonstrated that the surface acidity had a marked effect on the adsorption characteristics and that the effect was linked with the polarity of the solvents.  相似文献   
6.
The Radio on Fiber (ROF) technique has great potential in wireless communication systems. In this paper, we report on a fundamental examination of microwave wireless access systems based on Radio on Fiber. First, we designed and constructed examination systems by applying dual band (2.4 and 5 GHz) multiservice transmission systems and confirmed that there was sufficient performance through a transmission experiment. Then, application of FP‐LD (Fabry Perot Laser Diode) was considered in order to reduce the system cost, and for the most part degradation of the transmission characteristics was not observed when FP‐LD was used. Finally, a BIDI (bidirectional) module which integrated LD and PD within one package was made to further reduce costs. By measuring the transmission performance, applying the BIDI module to ROF systems was shown to be effective. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 160(4): 32–40, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20471  相似文献   
7.
Heterogeneous curable compositions of divalent metal salts of mono(hydroxyethyl) phthalate–anhydride–bisphenol A diglycidyl ether (BADG) systems were prepared by merely mixing these components at room temperature. Stability at room temperature and cure properties at high temperature of the compositions were investigated for evaluating their applicability as one part adhesive. It was found that the systems containing Mg were generally more stable than those containing Ca. Similarly, at 150°C the Ca-containing systems showed generally shorter gelation time than the Mg-containing ones, due to the fact that the Ca salt dissolves more rapidly and enters into the addition reaction with the anhydride, leading to the faster appearance of the catalytic activities of the Ca carboxylate group. Among the various combinations of components, the metal salt–succinic anhydride (SA)–BADG systems were stable at room temperature for more than 6 months and rapidly cured at high temperature, showing excellent adhesive properties. This result indicates that the SA-containing systems should be of interest in applications to one part adhesives.  相似文献   
8.
Chronic granulomatous disease (CGD) of childhood is a rare inherited disease in which phagocytic cells fail to produce the normal respiratory burst in response to infectious stimuli, leaving the patient particularly susceptible to infections with bacteria and fungi that produce catalase. Between 1988 and 1993 at the NIH, 58 pulmonary cytology specimens were obtained on 24 CGD patients. The number of specimens per patient ranged from one to 13 with an average 2.4. The 58 specimens included: 33 bronchoalveolar lavages; one bronchial brushing; 20 lung or pleural mass fine-needle aspirates; three pleural fluids, and one sputum. Two lung aspirates with insufficient material, five bronchoalveolar lavages performed post-treatment to confirm clinical resolution of disease, and two bronchoalveolar lavages not submitted for culture were excluded from further analysis. Of the 49 remaining specimens obtained from patients clinically suspected of having a pulmonary infection, cytology demonstrated a pathogenic organism in nine (18%). Microbiologic cultures were positive in 19/49 (39%). Cytology identified fungus in 8/13 (62%) of documented fungal infections, including four cases where microbiology was negative. Bacterial and mixed bacterial/fungal infections were usually not detected by cytology even with appropriate strains. No organisms were identified by cytology in the four cases of nocardia or the three cases of pseudomonas infection. The combination of cytology and microbiology provided the greatest diagnostic sensitivity, yielding a diagnosis in 22/49 cases (45%). Of the 27 cases with negative cytology and microbiology, an infectious agent was identified in eight upon submission of additional material: three cytology specimens and five tissue specimens. In the remaining 19 cases, no organisms were identified, however, the patients were treated presumptively. Characteristic pathologic features of granulomatous inflammation, necrosis, and giant cells were present in fine-needle aspirates, often when on organisms could be identified, but were not seen in other types of respiratory specimens.  相似文献   
9.
From the relationship between structures of the 2-substituents of verbanyl analogs and their sex pheromone activities to the American cockroach, electron density of the carbonyl oxygen atom in the substituent, as estimated by the [17O]NMR chemical shift, was estimated to be an important factor which influenced the activity, in addition to length of the substituent and the position of the carbonyl group. (+)-Verbanyl methylcarbonate (XX), possessing the highest electron density on the carbonyl oxygen atom, showed the strongest activity among the analogs.For Part X, see Manabe et al., 1983. J. Chem. Ecol. 9:533–549.  相似文献   
10.
Previously we reported that serum CA125 level is elevated in cases of pericardial effusion. We report three cases in which serum CA125 measurement is useful for assessing clinical status. In case 1, a 19-year-old came to our hospital for cardiac tamponade. Moderate degree of pericardial effusion and high CA125 level were observed. After the pericardectomy the serum CA125 level was normalized and pericardial effusion disappeared. Case 2, a 50-year-old man with mesothelioma and in whom serum CA125 level was elevated with pericardial effusion. After cardiac drainage his condition improved, with decreased CA125 level. However, later the CA125 level rose and recurrent localized pericardial effusion with worsening condition was observed. In case 3, in a 78-year-old woman with pericardial effusion no recurrence was observed after pericardial drainage. Her CA125 value was normal. These results indicated that measurement of CA125 value is a useful marker for assessing the clinical course of this disease.  相似文献   
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