Time-place learning in the eight-arm radial maze

Rats (n=4) searched for food on an eight-arm radial maze. Daily 56-min sessions were divided into eight 7-min time zones, during each of which a different location provided food; locations were randomized across subjects before training. The rats obtained multiple pellets within each time zone by leaving and returning to the correct location. Evidence that the rats had knowledge about the temporal and spatial features of the task includes the following. The rats anticipated locations before they became active and anticipated the end of the currently active locations. The rats discriminated currently active locations from earlier and forthcoming active locations in the absence of food transition cues. After the rats had left the previously active location, they visited the next correct location more often than would be expected by chance in the absence of food transition cues. The rats used handling or opening doors as a cue to visit the first location and timed successive 7-min intervals to get to subsequent locations.     

The Influence of the Teaching and Learning Environment on the Development of Generic Capabilities Needed for a Knowledge-Based Society

The effect of the teaching and learning environment on the development of generic capabilities was examined through a survey of 1756 undergraduate students at a university in Hong Kong. The survey assessed students' perceptions of the development of the six capabilities of critical thinking, self-managed learning, adaptability, problem solving, communication skills, and interpersonal skills and groupwork. Students were also asked to rate the quality of nine facets of the teaching and learning environment. Structural equation modelling was used to test a model of the influence of teaching on the nurturing of the six capabilities. The model grouped the nine facets of teaching and learning under the three higher-order latent variables of teaching, teacher–student relationship, and student–student relationship. The model showed a good fit to the data, indicating that the teaching and learning environment had a significant impact on the development of the generic capabilities while the students were taking their degree. The teaching latent variable had the strongest effect on the development of all six of the capabilities. A suitable teaching environment was characterised by a focus on understanding, the active participation of students in learning activities, a coherent curriculum, and assessment which focused on analytical skills and self-learning capability. Strong student–student relationships nurtured communication and interpersonal skills. There was a mutually reinforcing effect between the type of teaching, teacher–student relationships and student–student relationships.     

Automated soil resources mapping based on decision tree and Bayesian predictive modeling

This article presents two approaches for automated building of knowledge bases of soil resources mapping.These methods used decision tree and Bayesian predictive modeling,respectively to generate knowledge from training data.With these methods,building a knowledge base for automated soil mapping is easier than using the conventional knowledge acquisition approach.The knowledge bases built by these two methods were used by the knowledge classifier for soil type classification of the Longyou area,Zhejiang Province,China using TM bi-temporal imageries and GIS data.To evaluate the performance of the resultant knowledge bases,the classification results were compared to existing soil map based on field survey.The accuracy assessment and analysis of the resultant soil maps suggested that the knowledge bases built by these two methods were of good quality for mapping distribution model of soil classes over the study area.     

The pigeon’s discrimination of visual entropy: A logarithmic function

We taught 8 pigeons to discriminate 16-icon arrays that differed in their visual variability or “entropy” to see whether the relationship between entropy and discriminative behavior is linear (in which equivalent differences in entropy should produce equivalent changes in behavior) or logarithmic (in which higher entropy values should be less discriminable from one another than lower entropy values). Pigeons received a go/no-go task in which the lower entropy arrays were reinforced for one group and the higher entropy arrays were reinforced for a second group. The superior discrimination of the second group was predicted by a theoretical analysis in which excitatory and inhibitory stimulus generalization gradients fall along a logarithmic, but not a linear scale. Reanalysis of previously published data also yielded results consistent with a logarithmic relationship between entropy and discriminative behavior.     

Water-soluble UV curable urethane methyl acrylate coating: preparation and properties

Two kinds of water-soluble and ultraviolet (UV) curable oligomers were synthesized and characterized. The oligomers were evaluated as resins for water-based UV curable coating. The rheology of the two oligomers' aqueous solutions was investigated in terms of solid fraction, pH dependence, and temperature dependence. The solutions were found to be Newtonian fluid showing rather low viscosity even at high solid fraction of 0.55. The drying process of the coatings and the properties of the cured coatings were studied by comparing them with water-dispersed UV-curable polyurethane methyl acrylate. It was evident that the water-soluble coating dried more slowly; and that the overall properties were inferior to those of the water-dispersed coating.     

Influence of hydroxypropyl methylcellulose edible coating on fresh-keeping and storability of tomato

The effect of application of cellulose-based edible coating, hydroxypropyl methylcellulose (HPMC) to mature-green tomatoes on the firmness and color was investigated. Tomatoes were stored at 20°C for up to 18 days. Firmness decreased as storage time increased in all treatments. However, application of HPMC edible coating delayed softening of tomatoes during 18 days of storage at 20°C. At days 7, 13 and 18, the firmness of tomatoes coated with HPMC was significantly (P≦0.05) greater than the firmness of uncoated tomatoes. The study also confirmed that HPMC coatings could significantly (P≦0.05) delay the changes in color of tomatoes stored at 20°C. The ripening of tomatoes from the pink stage to the red stage was successfully retarded. HPMC coating could extend the shelf life of fresh tomatoes. The retardation of the rate of loss of firmness could reduce the economic loss that would result from spoilage by mechanical injury during transportation of tomatoes. Project partly supported by the Centers for Disease Control and Prevention, U.S. Public Health Service     

Using time dynamically in static intervals: Does it close the achievement gap?

A mixed-methods study was undertaken with 118 biology students in two urban high schools. A Student-Centered Adaptable Learning Environment (SCALE) was created to improve engagement from affective and cognitive perspectives using choice, creativity and technological allowances. Results demonstrated that fast and slow learners are generally separated by about 30 min in terms of inputting speeds, but can be as much as 65 min apart from one another. Given that traditional classrooms afford students only 45 min in which to learn, static time could have become a source of inequity in public schools. SCALE optimally allowed for the dynamic use of time in constrained periods, therefore reducing and even eliminating any negative relationships between speed of learning and resultant achievement gains in the block setting. Especially benefitting from their ability to maneuver were the slowest learners, who showed the largest achievement improvements in either time interval amongst ability groupings. As learning speed can be the most critical contributing component of resultant educational outcomes, providing students the ability to use time dynamically should be considered as a feasible solution to helping teachers reestablish equity in mixed-ability classrooms in public schools.     

投桃授荑 抛梅掷李——《诗经》赠遗兴象的民俗文化内涵

由《诗经》的花草果蔬等兴象可见出先秦婚恋习俗中的赠遗之风。初时 ,女子多任采集之责 ,故蔬果花草之属为女子用于赠答致爱、结恩定情甚是便宜 ,或以芍药、梅子、茅草等取用为求偶媒介 ,或以桃子、花椒等取意于繁殖性能 ,使自然界中的极普遍之物因寓含了特殊而神秘的象征意蕴而别有价值 ,另具风味。