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81.
Avoidance of a target flavor can be produced by providing rats with a highly nutritious solution of 20?% maltodextrin (20?%Malto) in some sessions and a 3?% maltodextrin (3?%Malto) solution containing the target flavor in intermixed sessions. Since 20?%Malto is both more nutritious and more palatable than 3?%Malto, flavor avoidance could arise because the flavor signals either a reduction in calories or reduced palatability, or both. Pilot testing established that rats strongly preferred 3?%Malto plus 0.1?% saccharin to both unflavored 3?%Malto and unflavored 20?%Malto. The two main experiments tested whether the palatability difference, which the pilot data had suggested was larger than the difference between 20?%Malto and 3?%Malto, could produce flavor avoidance. In both experiments, one group of rats were given 3?%Malto plus 0.1?% saccharin on some days, intermixed with other days on which this group was given 3?%Malto plus the target flavor, almond. Neither when trained and tested under conditions of food deprivation (Experiment 1) nor when trained and tested sated (Experiment 2) did palatability reduction produce almond avoidance. In contrast, calorie reduction produced almond avoidance under both conditions. These results suggest that flavor avoidance can be produced by intermixed training involving solutions that differ in nutritious value and palatability, but not when they differ only in palatability.  相似文献   
82.
Developing carriers of active ingredients with pre-determined release kinetics is a main challenge in the field of controlled release. In this work, we fabricate designer microparticles as carriers of active ingredients using droplet microfluidics. We show that monodisperse droplet templates do not necessarily produce monodisperse particles. Magnetic stirring, which is often used to enhance the droplet solidification rate, can promote breakup of the resultant microparticles into fragments; with an increase in the stirring time, microparticles become smaller in average size and more irregular in shape. Thus, the droplet solidification conditions affect the size, size distribution and morphology of the fabricated particles, and these attributes of the microparticles strongly influence their release kinetics. The smaller the average size of the microparticles is, the higher the initial release rate is. The release kinetics of drug carriers is strongly related to their characteristics. The understanding of this relationship enables the fabrication of tailor-designed carriers with a specified release rate, and even programmed release to meet the needs of applications that require a complex release profile of the active ingredients.  相似文献   
83.
84.
Hong Kong and Singapore were former British colonies, have a predominant Chinese population and value. They began to develop quickly in the late 1960s, become financial hubs of the world in the 21st century. This paper reviews the tertiary education development of the two cities, particularly on the perspective of university rankings. It first elaborates about the emergence of university rankings, and the reason why it becomes a growing exercise, and who would be the benefactors of these exercises. Then it examines the performance of universities of the two cities in the international university ranking systems, makes a general assessment about the relative merits of the higher education systems in both cities. The paper requests ranking comparisons on the detailed items rather than just the sums, and argues that universities in the two cities are on par.  相似文献   
85.
Based on some longitudinal studies of private tutoring in twelve cities, towns, municipalities and provinces of China, the paper endeavours to depict demand intensity, articulate market parameters and reflect on policy responses towards the demand-supply mechanism of the vast shadowy educational phenomena at primary and secondary levels. Such educational phenomena are so hidden that there is a complete lack of official statistical figures in measuring the full scale of tutoring and identifying tutors in some cases. In Hong Kong and Macao, parents and their schooling children take up responsibilities to consume various types of tutoring without state intervention into quality assurance. In Mainland China, local ministries of education prohibit home tutoring delivered by daytime teachers to their daytime students whilst take a laissez-faire approach towards mass tutorials that run in private business sphere. Lastly, a multi-level societal movement framework is recommended with strategic action plans in school practitioners’ and policy-makers’ perspectives for effectively monitoring or hampering the growth of such shadowy educational phenomena in China.  相似文献   
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