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Since the beginning of the 110th Congress, increased oversight by congressional committees into activities of the President and Executive Branch has sparked renewed interest in both political and legal questions involving the separation of powers. Congressional subpoenas for general information, documents, and testimony from high-ranking executive officials has not only generated significant inter-branch conflict but has also developed into a controversy that could result in a legal standoff between Congress and the President. Congress's ability to obtain access to information, whether in the form of documents or testimony, from the Executive is primarily enforced through political negotiation and accommodation that generally take place outside of public view. Contempt may be used by Congress to coerce compliance, punish the contemnor, and/or remove the obstruction. This paper focuses on Congress's contempt power and congressional authority to enforce its requests for information, documents, and testimony from both private individuals and the Executive Branch. First, it examines the source of Congress's contempt power. Next, it discusses and analyzes the procedures associated with each of the three different types of contempt proceedings—inherent contempt, statutory criminal contempt, and statutory civil contempt. Finally, this paper concludes by addressing several of the unique constitutional, legal, and political problems that are associated with congressional contempt proceedings against Executive Branch officials.  相似文献   
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Academic libraries are providing technical support and assistance to their patrons using models such as the information commons, learning commons, and designated service points. Applying a constructivist, experiential approach, one small liberal arts college created a team of students to provide peer-to-peer tech support in response to an influx of new technology resources and equipment available for checkout. This team has provided much-needed services to the campus and an important professional development opportunity for its members. This experience offers a useful example for implementing in-house technical support in libraries at similar institutions.  相似文献   
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Confidence intervals are difficult to teach, in part because most students appear to believe they understand how to interpret them intuitively. They rarely do. To help them abandon their misconception and achieve understanding, we have developed a simulation tool that encourages experimentation with multiple confidence intervals derived from the same population.  相似文献   
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In two experiments, we assessed whether rats optimize the number of reinforcers per response. In Experiment 1, one group of rats was trained to leverpress for food reinforcement on a simple variable-interval (VI) 60-sec schedule. For another group, a negative fixed-ratio component was imposed on the VI schedule to produce a conjoint contingency in which reinforcement became available on the VI schedule but was omitted when the ratio criterion was satisfied. In Experiment 2, one group of rats responded on a VI schedule and also received response-independent food. For another group, responding above a certain rate canceled the response-independent food. Despite the negative contingency experienced by the groups in Experiments 1 and 2, responding was maintained at a level at which the number of obtained reinforcers was reduced substantially below the maximum number possible. In addition, in both experiments, the groups that experienced the negative contingency responded at a lower rate than did a yoked control group that experienced the same frequency of reinforcement but lacked the negative component. These results demonstrate that although rats do not optimize their behavior with respect to reinforcement, they are nevertheless sensitive to some aspect of the instrumental contingency in operation.  相似文献   
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Research in Science Education - Set in the context of modeling-based learning (MBL), this research investigated the potential of epistemic frames as a theoretical and analytical framework for...  相似文献   
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ABSTRACT:  More than 76 million persons become ill from foodborne pathogens in the United States each year. To reduce these numbers, food safety education efforts need to be targeted at not only adults, but school children as well. The middle school grades are ideal for integrating food safety education into the curriculum while simultaneously contributing to national and state education standards in science, technology, and family and consumer sciences. For this project, a multimedia, self-paced online resource for delivering a food safety curriculum to middle school children was developed. Animated characters were used to deliver the lesson content. The application also included video segments, quiz feedback, and interactive games and activities. The effectiveness of the Web site was evaluated using validated cognitive and attitudinal assessment tools, and by comparing student cognitive gains to individual student learning styles. Participants were recruited from 6 middle schools in 5 states, totaling 217 students (20 sixth graders, 157 seventh graders, and 40 eighth graders). The results show that students had statistically significant modest gains in pretest to posttest knowledge and enjoyed using the Web site. The 6th grade students had significantly lower pretest to posttest improvement compared to 7th and 8th grade students, suggesting that this program may not be appropriate for this grade level. Furthermore, the results indicate that this Web-based computer application meets the needs of varying individual student learning styles.  相似文献   
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