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101.
The IEEE Computer Society Board of Governors remains focused on continuing the transformation of the Society so that we can provide increasing value to our membership. 相似文献
102.
Ruppel Susan E.; Fleming Carmen N.; Hubbard Timothy L. 《Canadian Metallurgical Quarterly》2009,63(1):49
The influence of feedback on representational momentum for the final location of a moving target was examined in 3 experiments. The presence of binary feedback (correct, error) during practise trials or during larger blocks of experimental trials did not reduce representational momentum, nor did the presence of more informative feedback specifying the direction of error (error—in front of, error—behind) during larger blocks of experimental trials reduce representational momentum. Effects on representational momentum of whether feedback was consistently provided were inconsistent. Even though feedback did not reduce representational momentum per se, feedback did influence the probability of a same response for different probe positions. Implications of the data for R. A. Finke and J. J. Freyd's (1985; J. J. Freyd, 1987) claim that representational momentum is impervious to error feedback, and possible roles of perceptual learning in representational momentum, are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
Selfhout Maarten; Denissen Jaap; Branje Susan; Meeus Wim 《Canadian Metallurgical Quarterly》2009,96(6):1152
The authors examined associations of perceived similarity, actual similarity, and peer-rated similarity in personality with friendship intensity during the acquaintanceship process in a naturalistic setting. Self- and peer-rated personality data were gathered from undergraduates (mean age = 18.9) at 5 time points during the first year of university using a round-robin design. Whereas perceived similarity and peer-rated similarity in personality were concurrently associated with more friendship intensity for just-acquainted individuals, actual similarity in personality was not. Further, bidirectional cross-lagged associations between perceived similarity and friendship intensity were found. Peer-rated similarity was also associated with increases in friendship intensity, and this association was mediated by communication frequency. These results indicate that specific types of similarity in personality are differentially associated with friendship intensity during early phases of acquaintanceship in a real-life setting. Further, insight was provided in the direction of causality between similarity and attraction: Perceived and peer-rated similarity seem to breed friendship intensity, whereas friendship intensity seems to breed perceived similarity only. Finally, peers’ expectations seem to affect individuals’ communicative behaviors, which in turn affect friendship formation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
A Green Revolution for Africa is emerging after decades of neglect of Africa’s agricultural systems. To counter these years of neglect, the then United Nations Secretary-General Kofi Annan called for “a uniquely African Green Revolution”. Since then, a number of initiatives have emerged or are emerging to realize this important vision. As more money and attention galvanizes much-needed action on the African Green Revolution, a vigorous debate is required to ensure that the mission of improving food security on the world’s poorest continent is achieved in the most effective, comprehensive and inclusive manner possible. The African Green Revolution cannot be limited to increasing yields of staple crops but must be designed as a driver of sustainable development, which includes gender empowerment and nutrition elements. This paper first reviews the Asian Green Revolution’s successes and shortcomings from a nutrition and gender perspective and then outlines what the global community can do to ensure that some of the limitations of the Asian Green Revolution, specifically with regard to nutrition and gender, are not repeated. 相似文献
105.
Non-porous ceramic membranes with mixed ionic and electronic conductivity have received significant interest as membrane reactor systems for the conversion of methane to higher value products. In this work, the role of the membrane in the conversion of methane and the interaction with a Pt/CeZrO2 catalyst has been studied. Pulse studies of reactants and products over physical mixtures of crushed membrane material and catalyst have clearly demonstrated that a synergy exists between the membrane and the catalyst under reaction conditions. The degree of catalyst/membrane interaction strongly impacts the conversion of methane and the catalyst performance. 相似文献
106.
Jefferson R. Surles Susan Morris-Natschke Michael H. Marx Claude Piantadosi 《Lipids》1993,28(1):55-57
Phospholipids containing a 1-alkylamido linkage have shown promisingin vitro neoplastic cell growth inhibitory properties and anti-human immunodeficiency viral activity. We have synthesized a series
of alkylamido ether lipid analogues on a milligram scale for initial evaluation, but for furtherin vivo testing of these bioactive phospholipids, synthesis on a larger scale is required. The multigram synthesis of 1-alkylamido
ether phospholipids was accomplished by modifying reaction conditions in the amidation step and changing reagents and solvent
systems in both the detritylation and phosphorylation steps. This was most crucial in the phosphorylation step, where in the
multigram synthesis 2-bromoethyl dichlorophosphate in diethyl ether/tetrahydrofuran (7∶3, vol/vol) gave much improved yields
as compared to the 2-chloro-2-oxo-1,3,2-dioxaphospholane reagent. The modifications also resulted in a product that could
be more easily purified in sufficient quantities for use inin vivo inhibition studies. 相似文献
107.
The photochemical grafting of 2-hydroxyethylmethacrylate onto low-density polyethylene film is described. The grafting technique employed involved irradiating a solution of 2-hydroxyethylmethacrylate and benzophenone in acetone spread between films of poly(ethylene terephthalate) or glass and low-density polyethylene. After irradiation for 2 min, the contact angle of the polyethylene films with water fell from 97° to about 50°. The contact angle of the poly(ethylene terephthalate) substrate also fell during grafting. X-ray photoelectron spectroscopy was consistent with the presence of poly(2-hydroxethylmethacrylate) at the surface of the polyethylene. The effect of solvent on the photochemical grafting of 2-hydroxyethylmethacrylate onto low-density polyethylene is discussed. © 1993 John Wiley & Sons, Inc. 相似文献
108.
Capital cost correlations are given for heat exchangers and furnaces. Correlations available in the literature and current data are compared on a consistent basis. Forty-six graphs show the relative magnitude of the different correlations and the recommended correlation for each type of equipment is summarized in a table. Some data on the costs of installing heat exchange equipment are given. 相似文献
109.
Susan Owens 《Energy Policy》1985,13(6):546-558
During the latter half of the 19ar 1970s there was great concern about potential conflicts over energy development proposals in the UK, most of which were expected to emerge within the framework of land use planning procedures and the associated opportunities for public participation. While there has been widespread dissatisfaction with the way in which the planning system handles energy developments, there is little consensus about the nature of the problem or about possible solutions to it. Greatly reduced energy forecasts allow a pause for reflection, but it is argued that there is no room for complacency about conflict over energy developments in future. 相似文献
110.
Along 25 km of the Lake Ontario shoreline near Toronto, Ontario, small coastal embayments (0.4–32 ha) have been constructed or modified by lake-infilling to restore warmwater fish habitat. The variation in thermal habitat quality for warmwater fishes among these embayments is very high; temperatures range from those found within a small pond to those of much cooler Lake Ontario. Since meteorological conditions and surface heat fluxes are almost identical, the temperature variation among embayments must be caused by differences in bathymetry or exchange with Lake Ontario. However, a previous study on these embayments found paradoxically that temperatures were not strongly associated with channel size or embayment bathymetry. This paper resolves the paradox by showing that flushing times for almost all of the constructed embayments were less than 1 day, and often less than 12 h. With so little time to warm within the embayments, water temperatures of almost all embayments remained very close to the temperatures of the adjacent lake waters. The coldest embayments connected directly to open Lake Ontario and warmer embayments connected to Lake Ontario through other embayments or protected harbors, where the inflowing water from Lake Ontario had already substantially warmed. To allow embayments along the exposed shoreline of Toronto to reach acceptable temperatures for warmwater fish, we use heat budgets to calculate that average summer flushing times must be increased from their current length of 1.5 to 5.5 h to approximately 30 h. Such changes could be achieved through large reductions in the channel cross section. 相似文献