A causal analysis relating previous achievement,attitudes, discourse,and intervention to achievement in biology and chemistry

This study described the relationship of 38 variates to achievement in high school biology and chemistry classes. Forty-four teachers prepared audio tape recordings of discussions throughout a nine-month period. Equal-sized groups received treatment consisting of wait time feedback and/or supportive intervention, a form of peer coaching. Other variables were initial measures, which included the variates of class size and previous science grade, pre- and posttest scores on student attitudes and perceptions, and prediscourse and discourse analyses, which included the variates of wait times, actions, and response durations. While previous research has shown that wait time feedback and supportive intervention are effective means of changing teacher behavior, the results of the present study revealed that previous student achievement and the attitudes of students accounted for 70% of the variation in the final examination scores (New York State Regents) on the basis of only the first three weeks of data collection on the variables assessed. Generally, little emphasis on higher-level thinking, wait time, or problem solving was found at the beginning of the school year, and only minimal changes resulted from the application of the treatment variables. Pressures for content coverage and preparation for externally imposed statewide examinations that emphasize memory-level learning augured against the changes that the independent variables were designed to produce.     

Methods for documenting historical agro-industrial buildings: a comparative study and a simple photogrammetric method

As an important element in the cultural heritage of a people, traditional rural constructions need to be conserved over time. Graphic and metric documentation methods play a key role in the preservation of cultural heritage. In this paper different existing methods of graphic and metric documentation are analysed in order to select the most suitable for the documentation of agro-industrial buildings according to their characteristics. The selected one is a simple close-range photogrammetry method, which is affordable and easy to understand for non experts. It is based on the use of plumb lines, a conventional digital camera and monoscopic restitution. The application of the method is illustrated in a particular case consisting on the graphic and metric documentation of a windmill. Also the accuracy of the method is evaluated in this particular case.     

Secret keys from quantum correlations

Quantum mechanics allows to create information-theoretical secure key based only on observed data. We review the current status of the resulting field quantum key distribution.