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991.
Soil transformation of 2(3H)-benzoxazolone of rye into phytotoxic 2-amino-3H-phenoxazin-3-one 总被引:4,自引:0,他引:4
Nonsterile soil transforms the rye metabolite 2(3H)-benzoxazolone (BOA) into 2-amino-3H-phenoxazin-3-one, which is an order
of magnitude more toxic to barnyard grass than benzoxazolone. Benzoxazolone was recovered unchanged from sterile soil. However,o-aminophenol is converted to aminophenoxazinone by both sterile and nonsterile soil in the presence of air. Aminophenoxazinone
is probably produced by microbial hydrolysis of benzoxazolone intoo-aminophenol, which is oxidized to aminophenoxazinone in both sterile and nonsterile soil. No 2,2′-oxo-1,1′-azobenzene was
found in any incubations of soil with benzoxazolone,o-aminophenol, oro-azophenol. 相似文献
992.
Butler Stephen F.; Newman Frederick L.; Cacciola John S.; Frank Arlene; Budman Simon H.; McLellan A. Thomas; Ford Sabrina; Blaine Jack; Gastfriend David; Moras Karla; Salloum Ihsan M.; Barber Jacques P. 《Canadian Metallurgical Quarterly》1998,10(4):399
The Addiction Severity Index (ASI) is a reliable and valid measure of problem severity among addicted patients. Concerns have been raised about the reliability of the Interviewer Severity Rating (ISR), a summary score for each of 7 domains. As part of an effort to build a computer-administered ASI, regression equations were developed to predict the ISR. Repeated resampling of a large dataset, consisting of 1,124 ASIs conducted by trained interviewers, permitted derivation of stable regression equations predicting the ISR for each ASI domain from patients' answers to preselected interview items. The resulting 7 Predicted Severity Ratings (PSRs) were tested on 8, standardized vignettes, with "gold standard," expert-generated ISRs. Reliabilities compared well with those of intensively trained interviewers. The PSRs could provide an alternative to potentially unreliable interviewer ratings, enhancing the ASI's role in treatment planning and treatment matching and make possible a computer-administered version of the ASI. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
William R. King 《Information Systems Management》1998,15(1):1-3
Applications of modern information technology - the management philosophy engendered by TQM and BPR, global networks, the Internet, intranets, mass customization and integrated logistics, and data warehousing and mining - have significantly affected business profitability and productivity. By standing ready to serve as innovators in continuing this trend, IS people will not only help their organizations compete, but will also help finally lay the productivity paradox to rest. 相似文献
994.
Hoffman James E.; Houck Michael R.; MacMillan Frank W. III; Simons Robert F.; Oatman Lynn C. 《Canadian Metallurgical Quarterly》1985,11(1):50
Investigated the role of limited capacity processes in the detection of automatic targets in a dual-task paradigm using both behavioral and event-related potential (ERP) measures. Six right-handed undergraduates served as Ss. An automatic detection task was paired with another concurrent discrimination while the relative importance of each task was systematically varied. The resulting performance operating characteristic showed that both the speed and accuracy of automatic detection responses were affected by the allocation of attention. Reductions in the accuracy of each task were accompanied by reductions in the amplitude of a late-positive component of the ERP (P300). The latency of the P300 component elicited by automatic targets was increased in dual-task conditions. A comparison of behavioral and ERP measures suggested the involvement of 2 separate limited-capacity processes in automatic detection: one concerned with the formation of an episodic representation of target occurrence and the other with the execution of rapid motor responses. (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
The behavior of Escherichia coli O157:H7 inoculated in 10% rehydrated nonfat dry milk adjusted to pH levels between 3.8 and 5.4 with lactic acid, salt levels of 0 to 6%, and diacetyl levels of 0, 5, and 10 micrograms/g was determined at 4 and 12 degrees C. Cell populations were determined by surface plating on tryptic soy agar after 7 and 35 days of incubation. Survival was also determined using retail cultured diary products. E. coli O157:H7 did not survive in skim milk at pH 3.8 and was reduced by 3 log cycles at pH 4.1, regardless of salt, diacetyl, and temperature levels. At pH levels above 4.4, survival was observed at lower salt concentrations for up to 35 days at both 12 and 4 degrees C. The organism grew (up to a 2.2-log increase) at pH 5.0 at 2% salt levels after 35 days of storage at 12 degrees C. Diacetyl at a concentration of 10 ppm had no effect on survival and growth. In all but one case, E. coli O157:H7 was inactivated in yogurt, sour cream, and buttermilk at a rate similar to or greater than what was consistent with the acidified skim milk data. Also consistent with the skim milk data, growth occurred in two of the three cottage cheese samples at 12 degrees C after 7 days but not after 35 days or at 4 degrees C, when a 1- to 2-log decline was observed. 相似文献
996.
OBJECTIVE: To compare the efficacy of IUI husband in natural versus FSH stimulated cycles. DESIGN: Prospective, controlled study. MATERIALS AND METHODS: IUI were performed in 57 infertile couples with natural cycles, and in 16 under FSH and GnRH stimulation (Short protocol). In stimulated patients also hCG and hydrogesteron were given. Indication in both groups was idiopathic infertility. Duration of infertility and the age were comparable. Semen preparation and ovarian monitoring were the same in 2 groups. RESULTS: Three pregnancies in 57 natural IUI cycles (5.3%) and 5 out of 16 cycles in stimulated women (31.2% per cycle-with one triple pregnancy). CONCLUSION: In couples with idiopathic infertility FSH stimulation significantly increases rate of pregnancy and multiple gestation. 相似文献
997.
Frank R. Juretzko Doru M. Stefanescu Brij K. Dhindaw Subhayu Sen Peter A. Curreri 《Metallurgical and Materials Transactions A》1998,29(6):1691-1696
Directional solidification experiments have been carried out to determine the pushing/engulfment transition for two different
metal/particle systems. The systems chosen were aluminum/zirconia particles and zinc/zirconia particles. Pure metals (99.999
pct A1 and 99.95 pct Zn) and spherical particles (500 μm in diameter) were used. The particles were nonreactive with the matrices within the temperature range of interest. The experiments
were conducted so as to ensure a planar solid/liquid (SL) interface during solidification. Particle location before and after
processing was evaluated by X-ray transmission microscopy (XTM) for the Al/ZrO2 samples. All samples were characterized by optical metallography after processing. A clear methodology for the experiment
evaluation was developed to unambiguously interpret the occurrence of the pushing/engulfment transition (PET). It was found
that the critical velocity for engulfment ranges from 1.9 to 2.4 μm/s for Al/ZrO2 and from 1.9 to 2.9 μm/s for Zn/ZrO2. 相似文献
998.
Effects of 3-pentanone and eight low molecular weight aliphatic alcohols and aldehydes identifed in the mixtures of volatiles released byAmaranthus palmeri S. Wats. (AMAPA) residues were determined on germination of onion, carrot, AMAPA, and tomato seeds. Three-day exposures to these volatiles significantly inhibited germination of these assay seeds, and the inhibition was dependent upon exposure time and concentration. Based on the degree of inhibition observed in both time- and concentration-dependent assays, the following activity series was obtained: 2-heptanol > 3-methyl-1-butanol, 1-hexanol > hexanal, 1-pentanol, 3-pentanone, acetaldehyde > ethanol, 2-methyl-1-propanol. The activities of this group of compounds with that of 2-heptanone appear to be additive and related to test compound volatility and hydrophilicity. 2-Heptanol and 2-heptanone also significantly inhibited the germination of other species, including shepherdspurse, soybean, lettuce, alfalfa, common purslane, oats, and lovegrass.Name of companies or commercial products are given solely for the purpose of providing specific information; their mention does not imply recommendation or endorsement by the U.S. Department of Agriculture over others not mentioned. 相似文献
999.
1000.
Reviewed and critiqued the relevance of the DSM-III-R for school psychological practice. Five misguided assumptions on which the use of the DSM-III-R system is based are presented. These assumptions deal with (1) medical model conceptualization of behavior, (2) reliability, (3) validity, (4) relevance for special education placement, and (5) treatment validity. Based on a critical analysis of each assumption, it was concluded that the DSM-III-R is largely irrelevant for the practice of school psychology. The absence of treatment validity was judged to be the most substantial deficit of the DSM-III-R. An alternative classification system based on a functional analysis of behavior was proposed as being more relevant for assessment, classification, placement, and intervention with students who are behaviorally disordered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献