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1.
Margeaux A. Miller Prof. Dr. Ellen M. Sletten 《Chembiochem : a European journal of chemical biology》2020,21(24):3451-3462
Perfluorocarbons, saturated carbon chains in which all the hydrogen atoms are replaced with fluorine, form a separate phase from both organic and aqueous solutions. Though perfluorinated compounds are not found in living systems, they can be used to modify biomolecules to confer orthogonal behavior within natural systems, such as improved stability, engineered assembly, and cell-permeability. Perfluorinated groups also provide handles for purification, mass spectrometry, and 19F NMR studies in complex environments. Herein, we describe how the unique properties of perfluorocarbons have been employed to understand and manipulate biological systems. 相似文献
2.
The cyclooxygenase-2 (COX-2) is a potent enzyme that converts arachidonic acid to prostaglandins (PG), including PGE2, a key mediator of inflammation and angiogenesis. Importantly, COX-2 is activated in response to inflammatory stimuli, where it is also believed to promote the development and progression of head and neck cancers (HNC). COX-2 can mediate its protumorigenic effect through various mechanisms, such as inducing cell proliferation, inhibition of apoptosis, and suppressing the host’s immune response. Furthermore, COX-2 can induce the production of vascular endothelial growth factors, hence, promoting angiogenesis. Indeed, the ability of COX-2 inhibitors to selectively restrict the proliferation of tumor cells and mediating apoptosis provides promising therapeutic targets for cancer patients. Thus, in this comprehensive review, we summarized the reported differential expression patterns of COX-2 in different stages of head and neck carcinogenesis—from potentially premalignant lesions to invasive carcinomas. Furthermore, we examined the available meta-analysis evidence for COX-2 role in the carcinogenesis of HNC. Finally, further understanding of the biological processes of COX-2 and its role in orchestrating cell proliferation, apoptosis, and angiogenesis may give therapeutically beneficial insight to develop the management plan of HNC patients and improve their clinical outcomes. 相似文献
3.
The influence of Arnheim's work on the author's research began with an experiment on the perception of visual balance. Two later research projects emerged from the profound influence of Arnheim's stance toward creation in the visual arts as a serious, cognitive endeavor. A series of meta-analyses were first conducted to test the claim that learning in the arts transfers to nonarts cognitive domains, but little evidence was found. Past research on the transfer hypothesis was found to be lacking because of its failure to assess learning in the parent domain. Therefore, a new research project was carried out to identify kinds of learning in the parent domain of visual arts. We identified eight thinking dispositions developed in serious visual arts classes, setting the stage for more plausible transfer studies. This study demonstrates that the visual arts inculcate basic skills in perception and cognition that exist both in the arts and sciences. All of the skills the authors describe can, with some modification, be transferred to the science laboratory. As Rudolf Arnheim has taught us, visual thinking is everywhere. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
Sood Johanna R.; Cisek Edward; Zimmerman Joan; Zaleski Ellen H.; Fillmore Herbert H. 《Canadian Metallurgical Quarterly》2003,48(1):44
Objective: To replicate and extend P. A. Lichtenberg and colleagues' (1996) cross-disciplinary intervention to improve physical and mental health among older adults. Participants: 14 depressed older adults (6 treatment, 8 control). Setting: The short-term rehabilitation unit of an urban nursing home. Intervention: Occupational therapists were trained to treat depression using pleasant events and cognitive-behavioral therapies. Outcome Measures: Geriatric Depression Scale, the Short Form-12, and the Multi-Level Assessment Instrument: Activities of Daily Living. Results: No significant group differences were found in physical or mental health. However, more control group members (75%) than treatment group members (33%) were depressed at study completion. Conclusions: The treatment of depressive symptoms can be integrated with a nonmental health treatment modality. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
5.
Based on a contemporary cognitive-psychoanalytic theory (control-mastery theory; J. Weiss, H. Sampson, & Mount Zion Psychotherapy Research Group, 1986), this study proposed that college students have plans for college that consist of conscious and unconscious goals and obstructions to be overcome in meeting those goals. The construct of unconscious guilt was used to mediate the dual goals of autonomy and attachment. The idiographic plan-formulation method was adapted to derive plans for 12 sophomore women. Acceptable interjudge reliabilities and criterion validity were demonstrated, and several themes in the goals and obstructions were illustrated. Students worried more about mothers than about fathers, particularly when they perceived the mother as weak or needy. The potential of the method for generating inferences about unconscious process for normative development is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Ellen Y. Sun Kathleen B. Alexander Paul F. Becher Shyh-Lung Hwang 《Journal of the American Ceramic Society》1996,79(10):2626-2632
Interfacial microstructures in βP-Si3 N4 ( w )-Si-Al-Y-O-N-glass systems were investigated by systematically varying the nitrogen content and the Al:Y ratio of the glass matrix. High-resolution and analytical transmission electron microscopy (HREM and AEM) studies revealed that the interfacial microstructure is a function of the glass composition. No interfacial phases were formed in glasses with low Al:Y ratios and in glasses with high Al:Y ratios and low nitrogen content, whereas epitaxial growth of an interfacial layer (100–200 μm thick) on the βP-Si3 N4 ( w ) occurred in a glass matrix with high Al:Y ratio and high nitrogen content. The interfacial layer was identified to be a β'-SiAION phase. Interfaces containing the SiAION layer exhibited high debonding energy compared to Si3 N4 ( w )–glass interfaces. HREM studies indicated that the lattice-mismatch strain in the SiAION layer was relieved by dislocation formation at the SiAION–Si3 N4 ( w ) interface. The difference in interfacial debonding energy was, hence, attributed to the local atomic structure and bonding between the glass-β-Si3 N4 and the glass–β'-SiAION phases. This observation was clear evidence of the strong influence of glass chemistry on the interfacial debonding behavior by altering the interfacial microstructure. 相似文献
7.
Ellen Spolsky 《Computers and the Humanities》1993,27(5-6):323-329
Olsen is right to note what can be done with a good theory and the right machine. His particular theory, however, is not transferable to literary studies. If we need a new model, I would suggest that cognitive science can provide a few interesting ones. I have begun to do some work based on David Marr's VISION, in which he hypothesizes two levels of processing within the visual module. My speculation has been on the parallel existence of distinguishable levels of conceptual or language organization which would correspond to the viewer and object centered perspectives Marr describes for vision. I propose to explore the possibility that we may find here the model for the existence of stylistic individualism within overarching historical stylistic generalizations, and even more, that this may be what feminists are searching for when they try to resist being coopted by the masculine language of objectivity.
Ellen Spolsky teaches English literature and literary theory and is the Director of the Lechter Institute for Literary Research at Bar-Ilan University, Israel. Her latest book is Gaps in Nature: Literary Interpretation and the Modular Mind(SUNY Press, 1993). 相似文献
8.
Rice Catherine; Koinis Daphne; Sullivan Kate; Tager-Flusberg Helen; Winner Ellen 《Canadian Metallurgical Quarterly》1997,33(1):54
68 3-yr-olds received a standard appearance–reality task along with either a trick task, in which the appearance question was placed in the context of a deceptive game, or a reduced information processing task, in which a dual object (e.g., a sponge-rock) was presented along with an object that matched the dual object's identity (a sponge) and one that matched the dual object's appearance (a rock). Children were more likely to pass either the trick or reduced information processing task and fail the standard than the reverse. Thus, 3-yr-olds can grasp the distinction between appearance and reality (a) when their goal is to trick someone, which may prime them to think about the other's mental state, and (b) when they do not need to hold conflicting object identities in mind at the same time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
Soft sediments from the Detroit River were analyzed for the USEPA priority pollutants to generally characterize contaminant distribution. Forty-three were detected. Highest heavy metal concentrations were found in the Trenton Channel and immediately downstream of Grosse Ile. They ranged from an area mean (N = 2) of 0.19 mg/kg mercury to 338.7 mg/kg zinc (dry weight). Polynuclear aromatic hydrocarbons ranged from 0.1 mg/kg to 38.8 mg/kg (mean, N = 2) with the highest levels near Grosse Ile. PCBs ranged from 0.015 mg/kg to 1.7 mg/kg (mean, N = 2). Organochlorine pesticides were not detected except for a trace of heptachlor in one sample. Sediment contamination in the Detroit River is widespread with higher concentrations on the U.S. side downstream of the Rouge River and in the Trenton Channel. The significance of these in-place pollutants to biota and as a source to Lake Erie is still unknown. 相似文献
10.
A total of 188 employed mothers and fathers and their 5–7 yr-old child participated in a study of the relations between the nature of adults' work and their parenting attitudes and behaviors (a line of research influenced by both socialization and stress perspectives). In general, positive features of work (i.e., complexity of work with people, challenge, and stimulation) tended to be associated with both self-report and observational measures of developmentally sound parenting (e.g., less harsh discipline, more warmth and responsiveness). Interaction effects indicated that gender of parent and child further condition these relations. Analyses partially support the interpretation that conditions of work influence parenting through their effect on mood but also suggest that certain conditions of work may directly socialize behavior in the parental role (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献