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A synthetic route that allows modification of 1‐vinyl‐2‐pyrrolidone with an alcohol or thiol group in its 3‐position in a one‐pot reaction without using protecting groups is described. The strategy used to achieve this goal is the reaction of the carboxamide anion of 1‐vinyl‐2‐pyrrolidone with cyclic precursors of these functionalities. It is furthermore shown that VP‐monomers functionalized with OH groups are suitable for the preparation of the corresponding copolymers with pure VP. As a second application of the new compounds, we also describe the synthesis of the first asymmetric crosslinker based on VP.

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The “living” free radical ring‐opening polymerization of 2‐methylene‐4‐phenyl‐1,3‐dioxolane (MPDO) in the presence of ethyl α‐bromobutyrate/CuBr/2,2′‐bipyridine at various temperatures has been investigated. In comparison with the conventional ring‐opening polymerization of MPDO, a lower content of ring‐opened unit in the polymer was found. The results of ln[M]0/[M]) against polymerization time, (Mn)th and (Mn)NMR vs conversion, and GPC of the polymers are strongly indicative of the “living” polymerization process. Initiator efficiency was measured. The mechanism of polymerization, and the effect of pyridine on the polymerization mechanism were discussed.  相似文献   

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In this article, we review and evaluate changes in the depressive disorders section from DSMIV to DSM‐5. We describe characteristics of three new depressive disorders: disruptive mood dysregulation disorder, premenstrual dysphoric disorder, and persistent depressive disorder. We also discuss the controversial decision in DSM‐5 to remove the bereavement exclusion from the criteria for major depressive disorder. Next, we review the decision to replace the diagnosis of depressive disorder not otherwise specified with two new diagnoses: other specified depressive disorder and unspecified depressive disorder. Finally, we discuss the inclusion of two novel specifiers in the DSM‐5 depressive disorders section: “with anxious distress” and “with mixed features.” For each of these changes, we examine the relevant research and discuss implications of the changes for research and clinical practice.  相似文献   

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The soluble microtubule‐associated protein tau forms hyperphosphorylated, insoluble and filamentous inclusions in a number of neurodegenerative diseases referred to as “tauopathies.” In Alzheimer's disease, tau pathology develops in a stereotypical manner, with the first lesions appearing in the locus coeruleus and entorhinal cortex, from where they appear to spread to the hippocampus and neocortex. Propagation of tau pathology is also a characteristic of argyrophilic grain disease, where the tau lesions spread throughout the limbic system. Significantly, isoform composition and morphology of tau filaments can differ between tauopathies, suggesting the existence of distinct tau strains. Extensive experimental findings indicate that prion‐like mechanisms underly the pathogenesis of tauopathies.  相似文献   

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Reflections on the history of real‐world (applied) community psychologists trace their participation in the field's official guild, the Society for Community Research and Action (SCRA), beginning with the Swampscott Conference in 1965 through the current date. Four benchmarks are examined. The issues these real‐world psychologists bring to the field include academic and community legitimacy, community psychology as an interdisciplinary field, and politics and advocacy. Challenges these issues create among community psychologists—real‐world and academic—are briefly addressed. These reflections end with a vision of the future of community psychology that includes a strong recommitment to social change and social justice. © 2008 Wiley Periodicals, Inc.  相似文献   

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COVID‐19 has generated a global need for technologies that enable communication, collaboration, education and scientific discourse whilst maintaining physical distance. University closures due to COVID‐19 and physical distancing measures disrupt academic activities that previously occurred face‐to‐face. Restrictions placed on universities due to COVID‐19 have precluded most conventional forms of education, assessment, research and scientific discourse. Anatomists now require valid, robust and easy‐to‐use communication tools to facilitate remote teaching, learning and research. Recent advances in communication, video conferencing and digital technologies may facilitate continuity of teaching and research activities. Examples include highly‐interactive video conferencing technology, collaborative tools, social media and networking platforms. In this narrative review, we examine the utility of these technologies in supporting effective communication and professional activities of anatomists during COVID‐19 and after.  相似文献   

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Heavy‐atom substitution chemistry in donor–acceptor (D–A) conjugated polymers has gained increasing attention in the past few years. Overall, the introduction of “heavy” atoms (below C in group 14; below N in group 15; below S in group 16) into D–A conjugated polymers allows control over properties through relatively straightforward synthetic chemistry, and produces materials with high molecular weights (>20 000 g mol?1), strong absorption (ε ≈ 40 000 L mol?1 cm?1), narrow highest occupied molecular orbital (HOMO)–lowest unoccupied molecular orbital (LUMO) gaps (<1 eV), as well as high charge‐carrier mobility (>10?2 cm2 V?1 s?1). This Trend article aims to describe heavy‐atom substitution effects in D–A polymers, and their applications, by systematically examining representative polymer structures.

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The issue of co‐author relationships on medical sciences journal publications has become more pronounced as advances in technology have enabled collaboration across countries and institutions to occur much more efficiently. These relationships often have underlying political motivations and outcomes, including career advancement, attempting to increase prestige of a project, and maintaining research grants. Some authors may be listed as senior or honorary authors despite offering little or no contribution to the original research project. This may be done in an effort to enhance the gravitas of a research project, and attain publication in a highly regarded medical journal. The current review covers the topic of political co‐authorship and germane literature and lists strategies to combat this phenomenon. Such co‐authorship practices corrupt the integrity of the research process as they attempt to bypass the safeguard that medical journals and institutions have put in place to prevent fraud and falsification. A number of strategies have been proposed to combat the practice of co‐authorship, but it may ultimately be an unavoidable feature of contemporary medical research publishing that is difficult to police. Clin. Anat. 30:831–834, 2017. © 2017Wiley Periodicals, Inc.  相似文献   

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Ethylene/4‐methyl‐1‐pentene (E/4M1P) copolymers were synthesized by [Me2Si(η5‐Me4C5)‐(η1‐N‐tBu)TiCl2] and methylalumoxane (MAO) catalyst ( CG ) and analyzed by 13C NMR. The low regio‐ and stereoregularity of CG leads to spectral multiplicities which can be ascribed not only to differences in comonomer sequences but also to the presence of regio‐ and stereoirregularities. The tendency of CG to give a nearly random comonomer distribution gives rise to so far undetectable alternating sequences. The complete set of assignments proposed allows a satisfactory characterization of variously microstructured E/4M1P copolymers and the evaluation of the amount of regioirregular sequences in addition to the full determination of dyad and triad copolymer composition.

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“Personal” and “shared” aspects of sense of community identity are explored in a an established community in Durham City, England. Durham City has a history of over 1,000 years of continuous settlement, and is generally viewed as a stable and relatively harmonious setting. In the study 102 residents responded to a Community Response Questionnaire based on Puddifoot's taxonomy of elements of sense of community. The findings suggest the existence of three underlying “personal” dimensions of Sense of Community Identity (SOCI), namely, “Sense of Personal Support,” “Sense of Personal Contentedness,” and “Personal Involvement,” and three “shared” dimensions of SOCI, namely, “Perceived Community Engagement,” “Perceived Neighborliness,” and “Perceived Settledness.” This article discusses these findings and the prospect of creating a measure for comparative analysis around these dimensions. © 2003 Wiley Periodicals, Inc.  相似文献   

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