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1.
Some therapists hold that the Bobo and other aggressive toys should be excluded from the playroom as they elicit acting-out behavior that is transferred to the world outside the playroom. However, many therapists view the inclusion of these items as imperative elements that facilitate positive growth and maturation in the child. Interviews with authorities in the field of play therapy support the position that the inclusion of the Bobo is not only useful, but a therapeutic necessity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
The rationale for utilizing filial therapy as a treatment intervention with child witnesses of domestic violence while residing with their mothers in a shelter facility is explored and the effectiveness of an intensive 12-session filial therapy parent training group, conducted within 2-3 weeks, is described (n=11; aged 4-10 yrs). Results of analysis of covariance revealed that child witnesses in the experimental group significantly reduced behavior problems prevalent in child witnesses and significantly increased their self-concept as compared to child witnesses in the non-treatment comparison group. In addition, t-test results showed that mothers who facilitated treatment of the experimental group scored significantly higher after training on both their attitudes of acceptance and their empathic behavior. Comparative analysis revealed that intensive filial therapy as facilitated by the children's mothers was as effective in reducing behavior problems as was intensive individual play therapy and intensive sibling group play therapy as facilitated by professionally trained therapists. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
The hydrogenation of diene‐based polymers via diimide is a very attractive alternative to the conventional catalytic hydrogenation route based on gaseous molecular hydrogen. However, serious crosslinking always accompanies it and limits the end‐use properties of the polymers. Gel formation in polymers that are hydrogenated via diimide has been investigated in detail through an inspection of all the chemical reactions involved in the process. The results indicate that hydrogen peroxide decomposition, some reactions related to oxygen, and the redox reaction between hydrogen peroxide and hydrazine are capable of generating radicals. However, radicals generated in the aqueous phase do not appear to initiate the crosslinking of diene‐based polymers in the latex form. It is proposed that the primary radicals giving rise to crosslinking are generated in the polymer phase in situ, and the step responsible for generating these organic radicals is possibly the diimide disproportionation reaction. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1122–1125, 2005  相似文献   
4.
Data acquisition and supervisory control and data acquisition (SCADA) systems have evolved from mainframe-based systems to multilevel tiered systems to flat client-server architecture. This paper examines the necessity for this evolution and the technology that spurred it on. A rod mill is discussed as a case study  相似文献   
5.
Sequences highly similar (>95%) to the mouse mammary tumor virus (MMTV) env gene have been amplified from human DNA samples, including DNA samples from patients with breast cancer (BC) and persons who did not have BC. The sequences from human DNA were distinct from the MMTV sequences used as controls in these PCR reactions, indicating that these results are not simply due to contamination. In addition to both, mouse and human-related sequences were also amplified from some monkey and cat genomic DNA samples. These products were shown to be distinct from, but highly related to, the MMTV env gene, whereas, testing of other sources (lambda phage, snake, cockroach, sea urchin, chicken, or dog) demonstrated no specific amplification. A sequence 90% similar to the MMTV group antigen gene (gag) was amplified from cat DNA. These results indicate that DNA from vertebrate species other than rodents, including some but not all humans, monkeys, and cats, can contain sequences closely related to MMTV.  相似文献   
6.
Neodymium (Nd)‐based Ziegler–Natta catalyst has been well known for preparing polybutadiene rubber (BR) containing high, about 98%, cis−1,4 configuration with extremely low gel content providing superior resistance to low‐temperature fatigue and abrasion. However, its cost is more expensive than a conventional nickel (Ni)‐based catalyst. The Nd‐BR has poor processability with high cold flow due to its high linearity and molecular weight. To compare with a traditional process, the BR produced by Ni‐based catalyst has higher level of branching resulting in the better processability, but it contains medium amount of gel. To balance the catalyst cost and the BR properties, this article reported the influence of a solution containing Ni‐ and Nd‐based Ziegler–Natta catalyst (Ni/Nd) using diethyl aluminum chloride and triethyl aluminum as co‐catalysts on 1,3‐butadiene (BD) conversion and physical properties of the elastomeric materials based on obtained rubber (Ni/Nd‐BR). In the presence of toluene, the increase in the Ni/Nd molar ratio from 0.0/1.0 to 0.4/0.6 yielded Ni/Nd‐BR containing cis−1,4 units of 95%–96% with significantly decreasing both levels of vinyl−1,2 and trans−1,4 configurations from 0.26% to 0.13% and 4.44% to 3.07%, respectively. When cyclohexane was applied as the reaction media, 100% BD conversion was achieved and the Ni/Nd‐BR had very low content of vinyl−1,2 unit (0.07%). The mechanical properties in terms of tensile properties and abrasion resistance of the elastomer based on Ni/Nd‐BR having high cis‐1,4 and relatively higher trans−1,4 configurations were superior to elastomers based on commercial BRs produced by using Ni‐ and Nd‐based catalyst systems. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41834.  相似文献   
7.
8.
Additive manufacturing, sometimes referred to as 3D printing is a new, rapidly developing technology which has the potential to revolutionize fabrication of certain high value, complex products. Until now conventional elastomers have not been widely used in the additive manufacturing process. The goal of our work was to determine the feasibility of additive manufacturing using ink jet printing of elastomeric latex materials. Particle size, viscosity, and surface tension were measured for five different latex materials—poly(2‐chloro‐1,3‐butadiene), carboxylated styrene‐butadiene rubber, carboxylated butadiene‐acrylonitrile copolymer, natural rubber, and prevulcanized natural rubber. The XSBR latex was predicted as the one most likely to be printable. Printing trials carried out with the XSBR as the ink proved it to be printable, although technical problems of agglomeration and print head clogging need to be addressed and both the material and process need to be optimized for consistent printing to be achieved. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42931.  相似文献   
9.
Noncompliance is a common problem exhibited by children with developmental delay (DD; Walker, 1993). The authors evaluated whether performance on the Assessment of Basic Learning Abilities (ABLA) test would predict compliance of children with and without DD to instructions alone (IA) versus instructions with modelling and/or gestures (IMG) administered by their caregivers. The ABLA test uses standard prompting and reinforcement procedures to assess the ease or difficulty with which a testee is able to learn a simple imitation and five two-choice discriminations. Twenty-one children without DD and 16 children with DD were presented with five age-appropriate educational tasks by their respective caregivers in a structured teaching session that included IA on some trials and IMG on others. The ABLA test performance reliably predicted the compliance of the children in the two conditions, and the results were consistent across both groups. The results are important for providing information to caregivers on how best to instruct their children in an effort to increase compliance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Electron beam x-ray tomography is an imaging technique, which can provide cross-sectional images of an object of interest with about 1 mm spatial resolution at frame rates of up to 10,000 frames per second. As a non-intrusive method it is especially suited for studying multiphase flows. For this purpose we devised an experimental limited-angle scan setup which utilizes linear beam deflection to generate radiographic projections. This setup was employed in the study of gas–liquid flow in an experimental flow loop operated at different liquid and gas flow rates. Electron-beam tomography images were compared with image data of a wire-mesh sensor. The latter is a fast but intrusive imaging device which is commonly used in gas–liquid flow imaging and achieves comparable frame rates but at lower spatial resolution. As a novelty we implemented a dual-plane limited-angle electron beam x-ray tomography which allows us to gain information about the phase velocities using cross-correlation data analysis.  相似文献   
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