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81.
82.
Shigeng Li Kausick Auddy Peter Barber Tara J. Hansen Jisheng Ma Hans‐Conrad zur Loye Harry J. Ploehn 《Polymer Engineering and Science》2012,52(9):1888-1902
This study used in situ polymerization to prepare polyethylene terephthalate (PET) nanocomposites incorporating Ethoquad‐modified montmorillonite (eMMT), unmodified hectorite (HCT), or phenyl hectorite (phHCT) particles to study the impact of platelet surface chemistry and loading on thermal, mechanical, and gas barrier properties. eMMT platelets reduced the PET crystallization rate without altering the ultimate degree of crystallinity. In contrast, HCT and phHCT platelets accelerated the polymer's crystallization rate and increased its crystallinity. DMA results for thermally‐quenched samples showed that as T increased past glass transition temperature (Tg), HCT and phHCT nanocomposites (and control PET) manifested precipitous drops in G′ followed by increasing G′ due to cold crystallization; in contrast, eMMT nanocomposites had much higher G′ values around Tg. This provides direct evidence of eMMT reinforcement in thermally‐quenched eMMT nanocomposites. These results suggest that eMMT has a strong, favorable interaction with PET, possibly through Ethoquad‐PET entanglement. HCT and phHCT have a fundamentally different interaction with PET that increases crystallization rate and Tg by 11 to 17°C. Water barrier improvement in eMMT nanocomposites agrees with previously published oxygen barrier results and can be rationalized in terms of a tortuous path gas barrier model. POLYM. ENG. SCI., 52:1888–1902, 2012. © 2012 Society of Plastics Engineers 相似文献
83.
Professional psychology has increasingly moved toward evidence-based practice. However, instruments used to assess psychologists seeking licensure, such as the Examination for Professional Practice in Psychology (EPPP), have received relatively little empirical scrutiny. Therefore, the authors evaluated the available evidence in support of the EPPP’s validity and current use as a core component of professional licensure. Although the EPPP has in many ways been extensively evaluated, there is a paucity of criterion, predictive, and incremental validity evidence available. Further, several aspects of the content validation studies were examined, and the authors question whether the EPPP, as currently constructed, can meet its stated goals. Given that the EPPP is a high-stakes examination and given the authors’ best estimate (based on a sample of 16 states) that 35% of applicants fail the examination, it is recommended that the EPPP be more extensively evaluated. An outline of major decision points in this proposed evaluation process is provided, several suggestions for further research are proposed, and the field is encouraged to discuss these issues further. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
Daniel A. Barber Lee Stickells Daniel J. Ryan Maren Koehler Philip Goad 《Architectural Theory Review》2013,18(2):249-286
There is increasing interest among architectural historians in addressing environmental concerns on both historical and theoretical terms. Simultaneously, other fields have been looking to architectural scholarship to understand the historical relationship between the built and the natural environment. For architectural historians, and others, this has also involved correlating the shifting discourse on environment with a history of architectural transformations and disciplinary expansions. These engagements have made clear that the environmental history of architecture does not simply add more objects to the historical database, but also changes the terms of historical analysis, as new matters of concern and new conceptual frameworks come to the fore. This paper gathers together a dialogic set of projections from scholars responding to the question of how we might newly understand the historical relationship between the built and the natural environment, and the opportunities and challenges this new phase presents to scholars, design researchers, and architects. 相似文献
85.
Gibbons Mary Beth Connolly; Crits-Christoph Paul; Barber Jacques P.; Wiltsey Stirman Shannon; Gallop Robert; Goldstein Lizabeth A.; Temes Christina M.; Ring-Kurtz Sarah 《Canadian Metallurgical Quarterly》2009,77(5):801
The goal of this article was to examine theoretically important mechanisms of change in psychotherapy outcome across different types of treatment. Specifically, the role of gains in self-understanding, acquisition of compensatory skills, and improvements in views of the self were examined. A pooled study database collected at the University of Pennsylvania Center for Psychotherapy Research, which includes studies conducted from 1995 to 2002 evaluating the efficacy of cognitive and psychodynamic therapies for a variety of disorders, was used. Patient samples included major depressive disorder, generalized anxiety disorder, panic disorder, borderline personality disorder, and adolescent anxiety disorders. A common assessment battery of mechanism and outcome measures was given at treatment intake, termination, and 6-month follow-up for all 184 patients. Improvements in self-understanding, compensatory skills, and views of the self were all associated with symptom change across the diverse psychotherapies. Changes in self-understanding and compensatory skills across treatment were predictive of follow-up symptom course. Changes in self-understanding demonstrated specificity of change to dynamic psychotherapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
87.
This article presents a capability called Adaptive Decision-Making Frameworks (ADMF) and shows that it can result in significantly
improved system performance across run-time situation changes in a multi-agent system. Specifically, ADMF can result in improved
and more robust performance compared to the use of a single static decision-making framework (DMF). The ADMF capability allows
agents to dynamically adapt the DMF in which they participate to fit their run-time situation as it changes. A DMF identifies
a set of agents and specifies the distribution of decision-making control and the authority to assign subtasks among these
agents as they determine how a goal or set of goals should be achieved. The ADMF capability is a form of organizational adaptation
and differs from previous approaches to organizational adaptation and dynamic coordination in that it is the first to allow
dynamic and explicit manipulation of these DMF characteristics at run-time as variables controlling agent behavior. The approach
proposed for selecting DMFs at run-time parameterizes all domain-specific knowledge as characteristics of the agents’ situation,
so the approach is application-independent. The presented evaluation empirically shows that, for at least one multi-agent
system, there is no one best DMF for multiple agents across run-time situational changes. Next, it motivates the further exploration
of ADMF by showing that adapting DMFs to run-time variations in situation can result in improved overall system performance
compared to static or random DMFs. 相似文献
88.
Benztropine and its analogs are tropane ring-containing dopamine uptake inhibitors that produce behavioral effects markedly different from cocaine and other dopamine transporter blockers. We investigated the benztropine binding site on dopamine transporters by covalently attaching a benztropine-based photoaffinity ligand, [125I]N-[n-butyl-4-(4"'-azido-3"'-iodophenyl)]-4', 4"-difluoro-3alpha-(diphenylmethoxy)tropane ([125I]GA II 34), to the protein, followed by proteolytic and immunological peptide mapping. The maps were compared with those obtained for dopamine transporters photoaffinity labeled with a GBR 12935 analog, [125I]1-[2-(diphenylmethoxy)ethyl]-4-[2-(4-azido-3-iodophenyl)ethy l]p iperazine ([125I]DEEP), and a cocaine analog, [125I]3beta-(p-chlorophenyl)tropane-2beta-carboxylic acid, 4'-azido-3'-iodophenylethyl ester ([125I]RTI 82), which have been shown previously to interact with different regions of the primary sequence of the protein. [125I]GA II 34 became incorporated in a membrane-bound, 14 kDa fragment predicted to contain transmembrane domains 1 and 2. This is the same region of the protein that binds [125I]DEEP, whereas the binding site for [125I]RTI 82 occurs closer to the C terminal in a domain containing transmembrane helices 4-7. Thus, although benztropine and cocaine both contain tropane rings, their binding sites are distinct, suggesting that dopamine transport inhibition may occur by different mechanisms. These results support previously derived structure-activity relationships suggesting that benztropine and cocaine analogs bind to different domains on the dopamine transporter. These differing molecular interactions may lead to the distinctive behavioral profiles of these compounds in animal models of drug abuse and indicate promise for the development of benztropine-based molecules for cocaine substitution therapies. 相似文献
89.
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
90.
This paper presents a full reconstruction process of magnetic resonance images. The first step is to bring the acquired data from the frequency domain, using a Fast Fourier Transform algorithm. A Tomographic Image Interpolation is then used to transform a sequence of tomographic slices in an isotropic volume data set, a process also called 3D Reconstruction. This work describes an automatic method whose interpolation stage is based on a previous matching stage using Delaunay Triangulation. The reconstruction approach uses an extrapolation procedure that permits appropriate treatment of the boundaries of the object under analysis. 相似文献