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141.
142.
This article presents a metalogue discussion about the two focus articles and the six associated review essays on the topic of conceptual change as it applies to research, and science teaching and learning in museum settings. Through the lenses of a sociocultural perspectives of learning we examine the applicability of the ideas presented in the forum for museums and museum educators. First we reflect on the role that emotions can play in concept development; second, we reflect on the role of language, talk, and gestures to concept development and conceptual change in the short-lived nature of experiences and conversations in museums; and third, we consider the nature of objects as representations of science content in museum settings.
Jennifer D. AdamsEmail:

Jennifer D. Adams   is an assistant professor of science education at Brooklyn College, CUNY. She did her doctoral dissertation at the Graduate Center, CUNY on museum-based teacher education at the American Museum of Natural History. Her research focuses on informal science teaching and learning, museum education, and culturally relevant science teaching and learning. Lynn U. Tran   received her PhD in science education at North Carolina State University, and recently finished a post-doctoral fellowship with the Center for Informal Learning and Schools at King’s College London. She is currently a Research Specialist with the Center for Research, Evaluation, and Assessment at the Lawrence Hall of Science at the University of California, Berkeley. Her research focuses on the pedagogical practices and professional development of science educators who teach in museums. Preeti Gupta   is the Senior Vice President of Education and Public Programs at the New York Hall of Science. She is responsible for all programs and projects in the following divisions: Science Career Ladder, the Explainers who serve as interpretation staff, Professional Development, K-12 Student Programs, Digital Learning Programs, Science Technology Library and Public Programs. Ms. Gupta is a graduate of the Science Career Ladder, starting her career in museum education as a high school student. She is currently pursuing a PhD in Urban Education at the CUNY Graduate Center. Helen Creedon-O’Hurley   is a secondary science educator in New York City’s public schools. She is the president of the Science Council of New York City, a science educator organization, and is in the doctoral program in urban education at the Graduate Center, CUNY.  相似文献   
143.
The effect of sodium oxalate and methionine supplementation on stone-related constituents of urine was studied in 18 adult male guinea pigs. Their serum and tissue chemistry and histological changes in urinary tract and liver were also studied. The calciuretic effect of methionine was blocked by oxalate. The decrease in uric acid and citric acid, caused by oxalate, was offset by methionine. Oxalate-induced crystalluria and calcium and oxalate deposition in kidney tissue were lessened by methionine. Administration of Varuna, an indigenuous drug, to oxalate and methionine-supplemented animals prevented either totally or partially most of the urolithogenic effects of oxalate and methionine.  相似文献   
144.
Serum ferroxidase and albumin levels were determined in 98 patients of tubercuiosis, of whom 49 were freshly diagnosed, sputum positive (group-I) & 49 were completely treated patients (group-II). Forty nine age and sex matched healthy individuals were taken as controls. Mean±SD of serum ferroxidase and albumin levels in controls, group-I and group-II was found to be 864.35±106.35 IU/L & 3.91±0.234 g/dL, 1603.76±222.65 IU/L & 3.24±0.518 g/dL and 1001.78±201.63 IU/L & 3.82±0.43 g/dL, respectively. Serum ferroxidase in group I was significantly higher as compared to controls and group-II (p<0.01). The decreased levels of serum albumin in group I, as compared to control and group-II was statistically significant (p<0.01). Serum ferroxidase: albumin ratio (Ferroxidase in International Unit per gram of albumin) in group I (50.47±10.36 IU/g) was significantly higher than controls (22.22±3.3 IU/g), (p<0.001) while in group II it was significantly lower (26.72±7.18 IU/g, p<0.001) than group-I and close to control values. Serum ferroxidase: albumin ratio (IU/g) can therefore be incorporated as a surrogate marker to assist in diagnosis and prognosis of pulmonary tuberculosis.  相似文献   
145.
A study has been carried out on 250 CAD patients to see how the serum levels of three antioxidants i.e., Vitamin C, Bilirubin and Ceruloplasmin are related to the CAD risk factors and characteristics in these patients. The number of severe category CAD patients declined by 7–18% with increasing serum levels of the three antioxidants and, triple vessel disease declined by 14–20%. A decline of 39% in Myocardial Infarction (MI) occurred with increasing serum Ceruloplasmin. Serum Ceruloplasmin was significantly lower in the MI group compared to the non MI group CAD patients. There was a steady and a significant decline in the mean values of serum levels of cholesterol, Triglyceride, VLDL cholesterol along with BMI with increasing serum level. The study indicates that with increasing serum levels of the three antioxidants studied, the % MI along with % Triple vessel disease and severity of CAD goes down suggesting that the modifiable risk factors have to be suitably modified in order to maintain a reasonably high level of these antioxidants, as the risk factors are inversely related to the serum antioxidant levels.  相似文献   
146.
采用UMA方案后,用户在蜂窝网络和WLAN之间切换时可以保持语音和数据会话的无缝连续性,就像原来他们在蜂窝网络中的单元间移动一样透明.在WLAN和蜂窝网络间的呼叫中无缝切换能够确保用户的位置和移动不影响提供给用户的服务质量,用户对全部服务、位置和移动的感受是全透明的,不管是通过WLAN还是蜂窝网络连接,服务都完全一致的(如图1).  相似文献   
147.
Mindful breathing has been linked to changes in physiology, but we took the practice further by examining whether a mindfulness breathing intervention, a three-minute breathing exercise marked by focused attention on the sensations of breath, affected writing anxiety, and writing performance measures. In addition, we examined mindful breathing as an intervention for community college students—some of the most at risk and underprepared students in higher education in the United States. We compared Daly Miller Writing Apprehension surveys and narrative writing samples from 277 students enrolled in a freshman composition course at a southeastern community college, half of the class sections were randomly assigned to practice a mindful-breathing technique at the beginning of class sessions. Students in the class sections that practiced mindful-breathing group experienced a statistically significant decrease in writing apprehension and mechanical error scores from pre- to post-test when compared to students in the comparison class sections.  相似文献   
148.
This paper establishes connection between discrete cosine transform (DCT) and the discrete-time fractional Brownian motion process (dfBm). It is proved that the eigenvectors of the auto-covariance matrix of a dfBm can be approximated by DCT basis vectors in the asymptotic sense. This shows that DCT basis acts as discrete Karhunen–Loève transform (DKLT) for these processes in the approximate sense. Analytic perturbation theory of linear operators is used to prove this result. This result will be of great practical significance in applications where one is looking for an appropriate basis to work with signals that can perhaps be modeled as belonging to fBm processes. The utility of the proposed work has been illustrated with two real-life data (a) on compressive sampling based reconstruction of financial time-series and (b) in denoising gravitational wave event GW150914 data obtained from a binary black hole merger.  相似文献   
149.
150.
Cholinesterases belongs to class hydrolases. There are two types acetylcholinesterase and butyryl cholinesterase. Acetylcholinesterase present in nerve endings and also in the RBC membrane. It helps to maintain the shape and size of RBCs. Any change in shape and size of RBCs may affect the activity of Acetylcholinesterase. Thus this study aimed to estimate RBCs Acetylcholinesterase enzyme activity in various types of anemias and correlate the RBCs Acetylcholinesterase enzyme activity with various hematological indices such as Erythrocyte Sedimentation Rate (ESR), Mean Corpuscular Hemoglobin (MCH), Mean Corpuscular Hemoglobin Concentration (MCHC), Mean Corpuscular Volume (MCV), Red cell Distribution Width (RDW) etc. After obtaining ethical approval from Institutional ethics committee total of 100 samples were collected from Clinical Biochemistry laboratory, Kasturba Medical College, Manipal, Manipal University. 25 were having normal RBC indices, 12 with hemolytic anemia, 26 with microcytic anemia and 26 with macrocytic anemia based on peripheral smear report and RBC indices. Acetylcholinesterase were measured using Ellman’s method. RBC acetylcholinesterase activity was significantly increased in microcytic anemia (58.13 ± 5.4) and macrocytic anemia (76.87 ± 6.7) than normal group (37.62 ± 2.71). Also increased RBC acetylcholinesterase was seen in hemolytic anemia (48.11 ± 5.18) but the increase is not statistically significant. RBC acetylcholinesterase correlated negatively with hemoglobin (r = ?0.356, p = 0.001) and positively with RDW (r = 0.31, p = 0.003). To conclude RBC acetylcholinesterase activity can be used as one of the potential marker for various types of anemia.  相似文献   
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