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81.
A high-yielding fluorination of (triphos)Pt-R(+) has been achieved using an array of F(+) sources, with XeF(2) yielding R-F in minutes. The C-F coupling proved to be a stereoretentive process that proceeds via a concerted reductive elimination from a putative dicationic Pt(IV) center. The larger the steric congestion of the (triphos)Pt-C(sp3) (+) complexes, the more efficient the fluorination, seemingly a result of sterically accelerated C-F reductive elimination along with simultaneous deceleration of its competing processes (β-H elimination). 相似文献
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David A. X. Nayagam Richard A. Williams Jun Chen Kylie A. Magee Jennifer Irwin Justin Tan Peter Innis Ronald T. Leung Sue Finch Chris E. Williams Graeme M. Clark Gordon G. Wallace 《Small (Weinheim an der Bergstrasse, Germany)》2011,7(8):981-981
In vivo host responses to an electrode‐like array of aligned carbon nanotubes (ACNTs) embedded within a biopolymer sheet are reported. This biocompatibility study assesses the suitability of immobilized carbon nanotubes for bionic devices. Inflammatory responses and foreign‐body histiocytic reactions are not substantially elevated when compared to negative controls following 12 weeks implantation. A fibrous capsule isolates the implanted ACNTs from the surrounding muscle tissue. Filamentous nanotube fragments are engulfed by macrophages, and globular debris is incorporated into the fibrous capsule with no further reaction. Scattered leukocytes are observed, adherent to the ACNT surface. These data indicate that there is a minimal local foreign‐body response to immobilized ACNTs, that detached fragments are phagocytosed into an inert material, and that ACNTs do not attract high levels of surface fouling. Collectively, these results suggest that immobilized nanotube structures should be considered for further investigation as bionic components. 相似文献
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Roles of Levies for Sustainable Domestic Water Consumption 总被引:1,自引:1,他引:0
Sustainable development is the modern rhetoric to guide environmental or natural resources management. There are many ways to do this and one is the wider utilization of economic instruments, such as taxes and levies. Although such levies are becoming common in Australia and worldwide, the role of the taxes or levies is still limited. In many cases, these taxes/levies -although environmentally related- have a fiscal rather than a purely environmental motive, for example, the Natural Resources Management (NRM) Levy in South Australia. This study evaluates the NRM levy policy using one NRM region and focussing on the Adelaide urban community. Data was collected through a web-based survey with 770 respondents who answered 59 questions. The research found that community strongly prefers a levy calculated on the volume of water consumed. Respondents also indicated that they would use less water if the levy were calculated on the volume of water consumed. The clear implications of the results suggest that if a tax or levy aims to change water consumption behaviour then it should be based on the volume of water consumed not on property value. 相似文献
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Ray Lara A.; Miranda Robert Jr.; MacKillop James; McGeary John; Tidey Jennifer W.; Rohsenow Damaris J.; Gwaltney Chad; Swift Robert W.; Monti Peter M. 《Canadian Metallurgical Quarterly》2009,17(2):122
Topiramate, an anticonvulsant medication, is an efficacious treatment for alcohol dependence. To date, little is known about genetic moderators of side effects from topiramate. The objective of this study was to examine 3 single nucleotide polymorphisms (SNPs) of the glutamate receptor GluR5 gene (GRIK1) as predictors of topiramate-induced side effects in the context of a laboratory study of topiramate. Heavy drinkers (n = 51, 19 women and 32 men), 75% of whom met criteria for an alcohol use disorder, completed a 5-week dose escalation schedule to a target dose of either 200 or 300 mg or matched placebo. The combined medication groups were compared with placebo-treated individuals for side effects at target dose. Analyses revealed that an SNP in intron 9 of the GRIK1 gene (rs2832407) was associated with the severity of topiramate-induced side effects and with serum levels of topiramate. Genes underlying glutamatergic neurotransmission, such as the GRIK1 gene, may help predict heterogeneity in topiramate-induced side effects. Future studies in larger samples are needed to more fully establish these preliminary findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Across 6 studies, Whites expressed more negative attitudes toward strongly identified racial minorities than toward weakly identified minorities. Whites who personally endorsed worldviews that legitimize the status hierarchy were particularly likely to express negative attitudes toward strongly identified minorities relative to weakly identified minorities, whereas Whites who personally rejected status-legitimizing worldviews displayed the opposite pattern. In addition, Whites' biases against strongly identified minorities dissipated when strongly identified minorities expressed strong endorsement of status-legitimizing worldviews. These studies suggest that Whites do not distribute their prejudicial attitudes equally among all members of minority groups and that some subsets of minorities (the strongly identified) might bear the brunt of racial prejudice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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