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91.
24 couples seeking outpatient treatment for marital problems were randomly assigned to 1 of 4 treatment conditions and to 1 of 4 therapists. Two of the treatment formats involved the use of videotape feedback as part of the marital therapy procedure. To measure the expected additive effects of videotherapy techniques, comparisons between couples were made of marital adjustment, self-concept, and satisfaction with therapy (e.g., Marital Adjustment Scale, Pre-Counseling Inventory). At the conclusion of therapy, both marital adjustment reports and self-perception scores had significantly increased from the pretreatment data obtained for all groups. There was a significant therapist effect and a significant overall therapist-by-treatment format interaction, but the expected main effect for treatment format was not obtained. The interpretable patterns found in the significant therapist-by-treatment interactions suggest that there is an enhancement effect for at least some forms of psychotherapy in which some clinicians employ video techniques. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
92.
The requirements and issues associated with computational representations for planning extend beyond those apparent in real-time control, where a substantial, existing research literature informs designers. To assist in the identification of requirements for planning representations, this paper provides two resources: (1) a theoretical foundation drawn from computer science and (2) illustrations of representations and corresponding work practice for real-time control and planning for the US Shuttle program. Together, these resources illustrate the human role in the planning process, and the need for work practices and information that combine to assist human operators in interpreting a representation that is loosely coupled to the physical world while shared among and modified by multiple participants in the planning process.
Valerie L. ShalinEmail:
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93.
94.
Clifford Fourier transform on vector fields   总被引:1,自引:0,他引:1  
Image processing and computer vision have robust methods for feature extraction and the computation of derivatives of scalar fields. Furthermore, interpolation and the effects of applying a filter can be analyzed in detail and can be advantages when applying these methods to vector fields to obtain a solid theoretical basis for feature extraction. We recently introduced the Clifford convolution, which is an extension of the classical convolution on scalar fields and provides a unified notation for the convolution of scalar and vector fields. It has attractive geometric properties that allow pattern matching on vector fields. In image processing, the convolution and the Fourier transform operators are closely related by the convolution theorem and, in this paper, we extend the Fourier transform to include general elements of Clifford Algebra, called multivectors, including scalars and vectors. The resulting convolution and derivative theorems are extensions of those for convolution and the Fourier transform on scalar fields. The Clifford Fourier transform allows a frequency analysis of vector fields and the behavior of vector-valued filters. In frequency space, vectors are transformed into general multivectors of the Clifford Algebra. Many basic vector-valued patterns, such as source, sink, saddle points, and potential vortices, can be described by a few multivectors in frequency space.  相似文献   
95.
Contrasted 30 13–15 yr old delinquents who had attempted suicide with 120 delinquent controls. Multiple regression analyses showed that suicidal ideation, depression, gender, a tendency to act out, conflict with parents, childhood hyperactivity, and the interactions of gender with depression and with acting out accounted for 49% of the variance in suicide attempts. Females were found to attempt suicide 2? times as often as males. Females were also more likely to attempt suicide when depressed than were similarly depressed males. Male and female delinquents who engaged in a high level of acting out were equally likely to attempt suicide, but females who did not act out were more likely to attempt suicide than males who did not act out. Similarities between these adolescent attempters and adult suicide attempters described in the literature are discussed. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
96.
97.
Spherical Pd nanoparticles (2–8 nm) were immobilized on the nanometer-scaled platelets of montmorillonite (MMT) by means of cation exchange of Pd2+ for Na+ followed by chemical reduction. The resulting Pd catalysts were readily dispersible in water and polar solvents. Polarity design and thus, variation of the dispersion behavior was achieved by subsequent organophilic MMT modification involving cation exchange with N-alkyl and N-perfluoroalkylethyl pyridinium cations. This allowed for easy catalyst dispersion in a wide range of organic solvents. According to characterization by TEM, EDXS, AAS and WAXS the nanoparticle formation did not destroy the superstructure of unmodified and organophilic MMT. Catalysts were applied to hydrogenation, Suzuki–Miyaura C–C coupling and fluorous biphase catalysis. The tunable dispersion behavior of MMT catalysts was successfully employed to guarantee easy catalyst recovery and recycling.  相似文献   
98.
The big screen : We have devised a high‐throughput screening method for organic peroxide‐dependent P450 reactivity by taking advantage of a previously undescribed activity of catalase, which was used as reporter enzyme. This two‐step assay, followed by liquid chromatography/mass spectrometry analyses, allowed the facile identification of several new substrates for bacterial P450 enzymes.

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99.
Combinatorial biosynthesis meets combinatorial pharmacology, cyanobacterial style : A new antimitotic natural product with features of both dolastatins 10 and 15 was isolated from the same Floridian Symploca sp. sample that produced the histone deacetylase inhibitor largazole. Both agents in combination are more effective in inhibiting cancer cell proliferation than either agent alone.

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100.
Root-knot nematodes (Meloidogyne spp.) are obligate endoparasites of a wide range of plant species. The infective stage is attracted strongly to and enters host roots at the zone of elongation, but the compounds responsible for this attraction have not been identified. We developed a simple assay to investigate nematode response to chemical gradients that uses Pluronic F-127, a synthetic block copolymer that, as a 23% aqueous solution, forms a liquid at low temperature and a gel at room temperature. Test chemicals are put into a modified pipette tip, or ‘chemical dispenser,’ and dispensers are inserted into the gel in which nematodes have been dispersed. Meloidogyne hapla is attracted to pH gradients formed by acetic acid and several other Brønsted acids and aggregates between pH 4.5 and 5.4. While this pH range was attractive to all tested root-knot nematode strains and species, the level of aggregation depended on the species/strain assessed. For actively growing roots, the pH at the root surface is most acidic at the zone of elongation. This observation is consistent with the idea that low pH is an attractant for nematodes. Root-knot nematodes have been reported to be attracted to carbon dioxide, but our experiments suggest that the observed attraction may be due to acidification of solutions by dissolved CO2 rather than to CO2 itself. These results suggest that Pluronic F-127 gel will be broadly applicable for examining responses of a range of organisms to chemical gradients or to each other.  相似文献   
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