Employing authentic cases experienced by practitioners in educational contexts is critical to expanding students’ experience and engaging students in authentic problems to promote their real-world problem-solving skills. Although in real life, practitioners experience both success and failure and learn from both, little research has been done so far to conceptualize why and how failure should be employed in case-based learning (CBL) as a way to develop students’ abilities to solve ill-structured problems. The goal of this paper is to theoretically justify the need for integrating failure cases in CBL to help students become better problem solvers. To achieve this, this paper attempted to approach failure from the perspective of human error and proposed a classification of failure based on the degree of explicitness of human error involved in problem solving. Based on discussions of potential benefits and challenges of integrating different types of failure cases in education, this paper also proposed instructional design strategies that can help facilitate better use of failure cases.
Objective： To examine changes of blood oxidative-antiovidative level in schizophrenic patients and its relationship with clinical symptoms. Methods： Forty-six Chinese patients met DSM-IV （Diagnostic and Statistical Manual of Mental Disorders-iV） criteria for schizophrenia and fifty age- and sex-matched healthy controls were enrolled in the present study. Baseline psychiatric symptom severity was assessed with brief psychiatric rating scale, positive and negative syndrome scale on the blood draw day. Fresh blood samples were collected to measure levels of nitric oxide and lipid peroxide in plasma as well as activities of superoxide dismutase, catalase and glutathione peroxidase in red blood cells by spectrophotometric assays simultaneously. Results Comparison of the biochemical parameters indicated that the level of nitric oxide and lipid peroxide increased in patient group, which represented a positive correlation with positive scale scores; while the activities of three critical enzymes decreased and showed a negative linear correlation. Conclusion： This study showed that there are dysregulation of free radical metabolism and poor activities of the antioxidant defense systems in schizophrenic patients. Excess free radicals formation may play a critical role in the etiology of schizophrenia. Using antioxidants might be an effective therapeutic approach to partially alleviate or prevent the symptoms of schizophrenia. 相似文献
