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41.
History is bunk, declared Henry Ford; he wanted to sell new cars every year. For psychoanalysis history is not bunk; it is its very heart and guts. Like an individual or a nation, psychoanalysis lives its history and rediscovers it in every generation. Psychoanalytic pioneers, authors of new rallying cries and new theories, seem to think otherwise: History of psychoanalysis begins with them. The author suggests a different approach: to see the new as a historical continuity of the old. The advocates of the relational approach in psychoanalysis will be surprised to hear that Freud was a Sullivanian, even though--like the proverbial M. Jourdain who never heard the word prose--he never heard of the word interpersonal. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
42.
This paper examines the elastoplastic buckling of a rectangular plate, with various boundary conditions, under uniform compression combined with uniform tension (or compression) in the perpendicular direction. The analysis is based on the standard linear buckling equations and material behaviour is modelled by the small strain J2 flow and deformation theories of plasticity. A detailed parametric study has been made for Al 7075 T6 over a range of plate geometries (a/b=0.25–4,a/h≈20–100) and with three sets of boundary conditions (four simply supported boundaries and the symmetric combinations of clamped/simply supported sides). For sufficiently thin plates we recover with both theories the classical elastic results. However, for thicker plates there is a remarkable difference in the buckling loads predicted by these two theories. Apart from the expected observation that deformation theory gives lower critical stresses than those obtained from the flow theory, we report on the existence of an optimal loading path for the deformation theory model. Buckling loads attained along the optimal path—specified by particular compression/tension ratios—are the highest possible over the entire space of loading histories. By contrast, no similar optimum has been found with the flow theory. This discrepancy in the buckling behaviour, obtained from the two competing plastic theories, provides a possibly new illustration of the plastic buckling paradox. 相似文献
43.
Zvi C Koren 《Coloration Technology》1994,110(8):273-277
A linear gradient elution method has been applied to the HPLC analysis of plant and scale insect red anthraquinonoid mordant dyes and molluscan blue and red-purple indigoid vat dyes. The method enables the use of the same elution program for the determination of different chemical classes of dyes. In addition, it significantly shortens the retention times of natural anthraquinonoid dyes over those previously published. For the first time a new dye, probably dibromoindirubin, has been detected in the Murex trunculus sea snail. The dye families investigated include the ones most often found on ancient textiles and shards from dyeing vessels in Israel and other regions. 相似文献
44.
Zvi Cohen 《Journal of the American Oil Chemists' Society》1990,67(12):916-920
The red microalgaPorphyridium cruentum is a new source for eicosapentanoic acid (EPA) and arachidonic acid (AA) fatty acids of potential pharmaceutical value. The
conditions leading to a high content of either fatty acid were investigated. The highest EPA content was obtained under conditions
resulting in high growth rate (2.4% of ash free dry weight in Strain 1380-1d). High AA content was obtained under slow growth
conditions and was maximal in th stationary phase or under nitrogen starvation (2.9%). Strain 1380-la had the highest content
(1.9%) of arachidonic acid under exponential growth conditions. By imposing nitrogen starvation, it was possible to obtain
a lipid mixture which may be separated into AA and EPA rich fractions. 相似文献
45.
In this paper, the formalism of
Relational Transition Systems (RTSes)
is used to model data-intensive reactive systems, and
four RTS models of reactive systems based on temporal
logic programming, production systems,
recurrence equations, and Petri nets are presented.
The paper also describes different methods of comparison of the
expressive powers of various RTSes in terms of the trajectories
they can generate and carries out this
comparison for the four RTS formalisms.
It is shown that these formalisms have the same expressive power in
the deterministic case.
The paper also compares expressive powers of non-deterministic
production systems and non-deterministic
temporal logic programming systems.
It is shown that, although the two formalisms are incomparable in the
general case, their restricted versions are isomorphic to each other.
Received December 7, 1993 / January 26, 1995 相似文献
46.
The complete and parametrically continuous (CPC) robot kinematic modeling convention has no model singularities and allows the modeling of the robot base and tool in the same manner by which the internal links are modeled. These two properties can be utilized to construct robot kinematic error models employing the minimum number of kinematic error parameters. These error parameters are independent and span the entire geometric error space. The BASE and TOOL error models are derived as special cases of the regular CPC error model. The CPC error model is useful for both kinematic identification and kinematic compensation. This paper focuses on the derivation of the CPC error models and their use in the experimental implementation of robot calibration. 相似文献
47.
Zvi Cohen 《Journal of the American Oil Chemists' Society》1994,71(9):941-945
Interest in the polyunsaturated fatty acid eicosapentaenoic acid (EPA) as a therapeutic agent is steadily increasing. The
microalgaMonodus subterraneus produces EPA, which is concentrated mainly in the galactolipid fraction, as its major fatty acid. Nitrogen starvation increased
the fatty acid content but reduced the proportion and content of EPA to 19.5% (of fatty acids) and 1.8% (of dry weight), respectively.
Cultivation under low light intensity or high biomass concentration enhanced the proportion of EPA up to 36.7% of fatty acids
and the content to 4.4% of dry weight. Maximal EPA productivity of 25.7 mg·L−1·d−1 was obtained at the biomass concentration that resulted in the highest biomass productivity.M. subterraneus is thus one of the most promising candidates for phototrophic production of EPA. 相似文献
48.
Specificity of Pheromonal and Kairomonal Response of the Israeli Pine Bast Scale Matsucoccus josephi and Its Predator Elatophilus hebraicus 总被引:1,自引:0,他引:1
Ezra Dunkelblum Miriam Harel Fabienne Assael Kenji Mori Zvi Mendel 《Journal of chemical ecology》2000,26(7):1649-1657
It has been demonstrated previously that the sex pheromone of the Israeli pine bast scale, Matsucoccus josephi, (2E,5R,6E,8E)-5,7-dimethyl2,6,8-decatrien-4-one (1) is also a potent kairomone of the scale insect's predator Elatophilus hebraicus. Surprisingly, the sex pheromones of M. feytaudi (2) and M. matsumurae (3) also attract E. hebraicus. These results have prompted us to prepare a series of analogs of 1 with variations in the two moieties attached to the C=O group (4–9) in order to probe the structure–activity relationship of the pheromonal/kairomonal response of M. josephi and E. hebraicus. The most selective and active pheromone analog is 8, attracting only M. josephi males and the most selective and active kairomone analog is the M. feytaudi pheromone 2, attracting only adults of E. hebraicus. A dose–response field test of these analogs and the chiral and racemic M. josephi pheromone 1 indicates that the specificity is maintained at a broad range between 25 and 400 g corresponding to 1. Analog 5, which is neither a parapheromone nor a kairomone, and analog 8, which is only a parapheromone, are not inhibitory to M. josephi or to E. hebraicus. Our study indicates that alterations in the diene side chain of 1, common to all three Matsucoccus pheromones, strongly reduce the kairomonal activity while structural changes in the second side chain significantly reduce the pheromonal activity. The discovery of selective analogs of 1 has practical implications and enables specific monitoring of M. josephi or E. hebraicus. Particularly important is the possibility to mass-trap males of M. josephi without reducing the population of E. hebraicus. 相似文献
49.
The flooding limitations of liquid-liquid countercurrent two-phase flow in a phase transition extraction (PTE) column were investigated both experimentally and theoretically. The solvents used in the PTE process are partially miscible and posses a critical point of miscibility. In the experiments, the effect of the settlers’ inclination on the onset of flooding in non-isothermal PTE column was investigated. It was found that flooding conditions in the column can be postponed by using off-horizontal settlers. This led to the development of a novel structure of a PTE column with improved throughputs.A model is suggested for predicting flooding conditions in the PTE column. It combines a recently developed two-fluid model with improved theory-based closure relations for laminar stratified flow, with a non-isothermal model for evaluating the composition in the mixing section and the internal streams in the column. The results of the combined model favorably predict the experimental flooding flow rates. 相似文献
50.
Failure Waves in Glass 总被引:3,自引:0,他引:3
Stephan J. Bless N. Singh Brar Gennady Kanel Zvi Rosenberg 《Journal of the American Ceramic Society》1992,75(4):1002-1004
Failure waves have been recently observed in glass plates and rods struck by high-speed projectiles. These waves propagate into material that has been prestressed by a compressive shock. The wave propagation speed exceeds the maximum crack speed and is not constant. Behind the failure wave there is a total loss of tensile strength and a substantial drop in shear strength. The failure is explosive, leading to radial expansion in unconfined targets and presurization in confined targets. 相似文献