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991.
R. A. Grazzini P. R. Paul T. Hage D. L. Cox-Foster J. I. Medford R. Craig R. O. Mumma 《Journal of chemical ecology》1999,25(4):955-968
Anacardic acids, alkyl phenolic acids excreted by tall glandular trichomes of the garden geranium, Pelargonium xhortorum, confer small-pest resistance. Up to 90% of the trichome exudate from mite-resistant P. xhortorum inbreds consists of an unusual anacardic acid with an unsaturated omega-5 (5) alkyl chain. As fatty acids are biochemical precursors to anacardic acids, we examined by GC the fatty acid composition of leaves, pedicels, petals, sepals, mature seeds, and glandular trichomes from pest-resistant and pest-susceptible Pelargonium inbred lines to determine the localization of 5-fatty acids within plant tissues. The fatty acid composition of lipid classes (galactolipids, phospholipids, and neutral lipids) extracted from glandular trichomes from mite-resistant pedicels were also examined. 5-Fatty acids (16:111 and 18:113) were found only in the glandular trichomes from pest-resistant geraniums (27.2% in trichomes of pedicels) and were localized predominantly in the phospho- and galactolipids (phosphatidylinositol, 25.9%; phosphatidylcholine, 18.2%; monogalactosyldiglyceride, 15.5%; and diglactosyldiglyceride, 14.0%). 相似文献
992.
An innovative TPO, based upon a complex fluid, is described, which shows an unusual balance of physical properties. The effects of complex fluid composition are addressed in a statistically designed experiment. Physical performance, rheological effects, thermal analysis, and morphological characterization are reported. J. VINYL ADDIT. TECHNOL., 12:183–191, 2006. © 2006 Society of Plastics Engineers 相似文献
993.
994.
In this paper, we describe a hybrid tool for hardware formal verification that links the HOL (higher-order logic) theorem prover and the MDG (multiway decision graphs) model checker. Our tool supports abstract datatypes and uninterpreted function symbols available in MDG, allowing the verification of high-level specifications. The hybrid tool, HOL-MDG, is based on an embedding in HOL of the grammar of the hardware modeling language, MDG-HDL, as well as an embedding of the first-order temporal logic Lmdg used to express properties for the MDG model checker. Verification with the hybrid tool is faster and more tractable than using either tools separately. We hence obtain the advantages of both verification paradigms. 相似文献
995.
996.
Abstract. Kudo (On the testing of outlying observations. Sankhya 17 (1956), 67–73) has derived an optimal invariant detector of a single additive outlier of unknown position in the context of an underlying Gaussian process consisting of independent and identically distributed random variables. We show how this author's arguments can be extended to derive an invariant detector of an additive outlier of unknown position for an underlying zero-mean Gaussian stochastic process. This invariant detector depends on the parameters of this process; its properties are analysed further for the particular case of an underlying zero-mean Gaussian AR( p ) process. It provides an upper bound on the performance of any invariant detector based solely on the data and it may be 'bootstrapped' to provide an invariant detector based solely on the data. A plausibility argument is presented in favour of the proposition that the bootstrapped detector is nearly optimal for sufficiently large data length n. The truth of this proposition has been confirmed by simulation results for zero-mean Gaussian AR(1) and AR(2) processes (for certain sets of possible outlier positions). The bootstrapped detector is shown to be closely related to the detector based on the approximate likelihood ratio criteria of Fox (Outliers in time series. J. Roy. Statist. Soc. Ser. B 34 (1972), 350–63) and the leave-one-out diagnostic of Bruce and Martin (Leave- k -out diagnostics in time series. J. Roy. Statist. Soc. Ser B 51 (1989), 363–424). It is also shown how the case of an underlying Gaussian process with arbitrary mean can be reduced to the case of an underlying zero-mean Gaussian process. 相似文献
997.
Diagnosis and reduction of conducted noise emissions 总被引:3,自引:0,他引:3
A systematic method for the diagnosis and reduction of conducted noise emissions is described. The method consists of a device for determining whether the differential- or common-mode component of conducted noise is dominant along with a simplified equivalent circuit of the power supply filter for each component. The procedure consists of first using the device to determine which noise-component is dominant in a particular frequency range and then using the simplified equivalent circuits to determine whether an anticipated change in value of an element in the power supply filter will be effective 相似文献
998.
Linking service climate and customer perceptions of service quality: test of a causal model 总被引:2,自引:0,他引:2
A set of foundation issues that support employee work and service quality is conceptualized as a necessary but not sufficient cause of a climate for service, which in turn is proposed to be reflected in customer experiences. Climate for service rests on the foundation issues, but in addition it requires policies and practices that focus attention directly on service quality. Data were collected at multiple points in time from employees and customers of 134 branches of a bank and analyzed via structural equation modeling. Results indicated that the model in which the foundation issues yielded a climate for service, and climate for service in turn led to customer perceptions of service quality, fit the data well. However, subsequent cross-lagged analyses revealed the presence of a reciprocal effect for climate and customer perceptions. Implications of these results for theory and research are offered. 相似文献
999.
This paper presents a potential alternate method for determining operating capacity of motor-operated valves subjected to seismic and other applicable loadings. As a result of programs at nuclear facilities to ensure the operational capability of MOVs (under NRC GL89-10), extensive analytical focus to develop the structural capability of valves has ensued. In the past, seismic qualification of valves typically addressed the strength of the topwork structure to resist inertial loading from excitation of the large valve actuator mass. These evaluations paid little or no consideration to the loading resulting from valve closing forces. The focus of the recent efforts is to develop the maximum operational capability of the valve, in terms of thrust, with consideration of seismic and other services loading as applicable. The alternate method outlined in this paper presents a series of thrust capacity curves, with reduction factors for seismic loading which can be applied and developed to determine safe thrust loadings without performing extensive analytical effort. A similar approach was put forward by the SQUG GIP approach to MOVs to ensure the safe operation of valves based on past earthquake experience. However, the GIP approach cannot be used to determine safe operational loads and thus has limited use in the necessary analysis required for GL89-10 programs at nuclear facilities. 相似文献
1000.
Toro Paul A.; Reischl Thomas M.; Zimmerman Marc A.; Rappaport Julian; Seidman Edward; Luke Douglas A.; Roberts Linda J. 《Canadian Metallurgical Quarterly》1988,56(4):631
This study assessed the impact of professional involvement in mutual help groups for the mentally ill. Social climate data and behavioral data on members in groups led either by a mental health professional (n?=?36) or an indigenous group member (n?=?70) were compared. The results of the study indicated a more formal, psychologically directed approach in the professionally led groups. Although professional involvement in mutual help groups does not necessarily produce different member outcomes, it does seem to affect both the perceptions and the behavior of members. Professionals should be cautious when they get involved in mutual help groups to avoid professionalizing them. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献