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101.
Responds to the comments of P. L. Ackerman (see record 2006-12925-012), D. Y. Dai (see record 2006-12925-013), and M. C. Gridley (see record 2006-12925-014) on E. S. Spelke's original article "Sex differences in intrinsic aptitude for mathematics and science? A critical review" (see record 2005-15840-001). Here, the current authors first consider Ackerman's criticism of IQ measures of cognitive sex differences, as well as his suggestion that Advanced Placement tests be used as a second measure. Next, the authors discuss Dai's suggestion that cognition and motivation, abilities and strategies, are inseparably bound in any meaningful measure of aptitude for mathematics and science. Finally, the authors address Gridley's suggestion that differences in men's and women's thinking styles and preferences explain gender disparities in math and science fields. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
102.
The transport properties of a unique family of silane‐modified poly(vinyl chloride) (PVC) pervaporation membranes for the separation of halogenated hydrocarbons from water were investigated. The PVC was modified by using a vinyl silane to improve its resistance to attack by halogenated hydrocarbons and to increase the flux. Two preparation routes were used: Route i included an initiator to promote the vinyl reaction before the hydrolysis and condensation of the methoxy silane group, whereas Route ni did not. The structures of the membranes were characterized and related to the transport properties, as derived from batch pervaporation experiments. The permeability of unmodified PVC membranes increases with exposure to haloorganics at low concentrations. Initially, the modified membranes exhibited a higher permeability than PVC and a lower selectivity. At long pervaporation times, the silane‐modified membranes exhibited a higher selectivity than PVC. The different preparation routes led to different morphologies, which affected the performance of the membranes; Route ni membranes exhibited higher permeabilities and selectivity than Route i membranes. Rubbery polydimethylsiloxane membranes were resistant to haloorganics but their high water permeability and low selectivity make them unsuitable for this pervaporative separation. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1429–1438, 2001  相似文献   
103.
A novel method for the residue analysis of wine spoilage compound 2,4,6-trichloroanisole is reported. Wine (60 ml) was extracted with 2 ml toluene in presence of 24 g MgSO4 and 6 g NaCl. Cleanup of the toluene phase by dispersive solid phase extraction with mixture of 100 mg CaCl2, 25 mg primary secondary amine and 50 mg MgSO4 was effective in minimising co-extractives and matrix effects. Time-of-flight and tandem mass spectrometric parameters were optimised to achieve linearity over 0.25–500 ng ml−1 and method detection limit 0.0083 ng ml−1 which is well below the odour threshold of 0.04 ng ml−1. Recoveries at 0.04, 0.2 and 0.8 ng ml−1 were within 80–110% (±8%). The method was reproducible when tested for Argentinean wines with intra-laboratory Horwitz ratios being <0.20 in white and red wines at both the laboratories of India and Argentina. The method could be successfully applied for incurred wine samples.  相似文献   
104.
105.
We have demonstrated hyperspectral tip-enhanced Raman imaging on dielectric substrates using linearly polarized light and nanofabricated coaxial antenna tips. A full Raman spectrum was acquired at each pixel of a 256 by 256 pixel contact-mode atomic force microscope image of carbon nanotubes grown on a fused silica microscope coverslip, allowing D and G mode intensity and D-mode peak shifts to be measured with ~20 nm spatial resolution. Tip enhancement was sufficient to acquire useful Raman spectra in 50-100 ms. Coaxial scan probes combine the efficiency and enhanced, ultralocalized optical fields of plasmonically coupled antennae with the superior topographical imaging properties of sharp metal tips. The yield of the coaxial tip fabrication process is close to 100%, and the tips are sufficiently durable to support hours of contact-mode force microscope imaging. Our coaxial probes avoid the limitations associated with the "gap-mode" imaging geometry used in most tip-enhanced Raman studies to date, where a sharp metal tip is held ~1 nm above a metallic substrate with the sample located in the gap.  相似文献   
106.
Undefined microbial surface ripening consortia with anti-listerial activity were derived twice from mature retail red smear cheeses produced in factories R and K. Each of the four consortia (R , R , K , K ) was used for inoculation of soft cheeses, which were ripened according to two temperature regimes (13 °C, 13 d and 16 °C, 13 d/12 °C, 7 d, respectively) and subsequently stored at 8 °C. The protective potential of the cultures was determined by monitoring the growth of Listeria monocytogenes on the cheeses. While the protective potential of R and R was stable under both temperature regimes, the anti-listerial activity of cultures from factory K was affected by the ripening temperature. Identification of 1200 isolates revealed significant changes in the bacterial composition of all four consortia until the expiry date, while the flora successions clearly varied with different temperatures. It is shown that the temperature effect on the anti-listerial activity and composition of protective cultures in food production are individual characteristics of the respective consortia that can be monitored and used to optimize its contribution to food safety.  相似文献   
107.
Specifying and analyzing early requirements in Tropos   总被引:2,自引:1,他引:2  
We present a framework that supports the formal verification of early requirements specifications. The framework is based on Formal Tropos, a specification language that adopts primitive concepts for modeling early requirements (such as actor, goal, and strategic dependency), along with a rich temporal specification language. We show how existing formal analysis techniques, and in particular model checking, can be adapted for the automatic verification of Formal Tropos specifications. These techniques have been implemented in a tool, called the T-Tool, that maps Formal Tropos specifications into a language that can be handled by the NuSMV model checker. Finally, we evaluate our methodology on a course-exam management case study. Our experiments show that formal analysis reveals gaps and inconsistencies in early requirements specifications that are by no means trivial to discover without the help of formal analysis tools.
Marco RoveriEmail:
  相似文献   
108.
The effects of UV‐C (4.1 kJ m?2) and heat treatment (45 °C, 3 h in air) either separately or combined on the quality of strawberries (Fragaria × ananassa cv Seascape) at the 75 or 50% surface red ripening stage were assessed, the latter stage being used only in the firmness test. In addition, the development of surface fungal infections was followed and in vitro germination assays on conidia of Botrytis cinerea and Rhizopus stolonifer performed. Both heat and combined treatments, decreased hue and delayed changes of the L* parameter. All treatments reduced the accumulation of anthocyanins. Control fruit softened most while fruit treated by the combined method were the firmest. The combined treatment reduced fungal infections and delayed in vitro germination of Botrytis cinerea conidia. After 2 days at 20 °C, treated fruit had lower amount of phenolics than the control. Neither the heat nor UV‐C irradiation modified the total sugar content, although the combined treatment decreased it slightly relative to the control. Titratable acidity increased through storage at 20 °C in all fruit, but no differences between control and treated fruit were detected. The combination of UV‐C and heat treatments enhanced the benefits of applying each treatment separately, and could be useful to improve and extend strawberry fruit postharvest life. Copyright © 2004 Society of Chemical Industry  相似文献   
109.
In this paper, we examine the ideological implications of racial stereotypes in comedy through a textual and audience analysis of Rush Hour 2 . Although Asian, Black, and White focus group participants differentially engaged with racial stereotypes in the film, most participants, regardless of race, found the film's racial jokes inoffensive. Many Asian and Black participants found a positive source of pleasure in the negative portrayals of their own race and did not produce oppositional discourse. Our study suggests that the generic conventions and textual devices of comedy encourage the audience to naturalize racial differences rather than to challenge racial stereotypes.  相似文献   
110.
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