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21.
The University of Helsinki established a Teachers’ Academy to reward excellence in teaching. This study focuses on teachers’ significant networks and their meaningful conversations about teaching and learning before the establishment of the Teachers’ Academy. The research data consisted of answers to open-ended questions, and were examined using social network analysis. The teachers’ network consisted of significant relations with (1) colleagues and other teachers, (2) peers in pedagogical courses and pedagogical experts, (3) students, and (4) family members and friends. The conversations with different parties varied in nature, content and the level of confidentiality.  相似文献   
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European Journal of Psychology of Education - School motivation is key to promoting optimal educational pathways. Some studies suggest that parental monitoring behaviors foster school motivation...  相似文献   
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In this paper, we present a functional variable method for finding periodic wave and solitary wave solutions of complex nonlinear evolution equations in mathematical physics and engineering sciences. The proposed technique is tested on the generalized Zakharov equation and higher-order nonlinear Schrödinger equations. The method is straightforward and concise, and it can also be applied to other nonlinear evolution equations in applied mathematics.  相似文献   
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The initial time difference practical stability in terms of two measures has been investigated for nonlinear fractional differential equations in Caputo's sense and these properties have been unified with Lyapunov-like functions to establish a comparison result.  相似文献   
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Background:

The ultra-large von Willebrand factor (vWF) multimers are very active and must be degraded by ADAMTS13 for optimal activity. A severe functional deficiency of ADAMTS13 has been associated with thrombotic thrombocytopenic purpura. The correct interpretation of patient vWF and ADAMTS13 plasma levels requires an understanding of the biological variation associated with these analytes. In the present paper, we aimed to determine the biological variation of ADAMTS13 and vWF in human adults.

Materials and methods:

Blood samples were collected weekly from 19 healthy subjects for 5 consecutive weeks. vWF activity and antigenicity were determined using aggregometric and immunoturbidimetric methods. ADAMTS13 antigenicity and activity were determined by ELISA.

Results:

The within-subject biological variations for vWF activity and antigenicity were 8.06% and 14.37%, respectively, while the between-subject biological variations were 18.5% and 22.59%, respectively. The index of individuality for vWF activity was 0.44, while vWF antigenicity was 0.64. Similarly, ADAMTS13 activity and antigenicity within-subject biological variations were 12.73% and 9.75%, respectively, while between-subject biological variations were 9.63% and 6.28%, respectively. The ADAMTS13 indexes of individuality were 1.32 and 1.55, respectively.

Conclusion:

We report high biological variation and individuality in vWF antigenicity and activity levels. However, ADAMTS13 antigenicity and activity displayed high biological variation, but low individuality. Thus, population-based reference intervals may be useful for monitoring ADAMTS13 antigenicity and activity, but not for vWF, which displays high individuality. These findings should be considered when determining the reference interval and other clinical variables associated with ADAMTS13 and vWF levels.  相似文献   
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Introduction:

There are a number of pre-analytical and analytical factors, which cause false results in the complete blood count. The present case identifies cold agglutinins as the cause for the mismatch between hematocrit and hemoglobin values.

Materials and methods:

70-year old female patient had a history of cerebrovascular diseases and rheumatoid arthritis. During routine laboratory examination, the patient had normal leukocyte and platelet counts; however, the hemoglobin (Hb: 105 g/L) and hematocrit (HCT: 0.214 L/L) results were discordant. Hemolysis, lipemia and cold agglutinin were evaluated as possible reasons for the mismatch between hematocrit and hemoglobin values.

Results:

First blood sample was slightly hemolysed. Redrawn sample without hemolysis or lipemia was analyzed but the mismatch became even more distinct (Hb: 104 g/L and HCT: 0.08 L/L). In this sample, the titration of the cold agglutinin was determined and found to be positive at 1:64 dilution ratios. After an incubation of the sample at 37°C for 2 hours, reversibility of agglutination was observed.

Conclusion:

We conclude that cold agglutinins may interfere with the analysis of erythrocyte and erythrocyte-related parameters (HCT, MCV, MCH and MCHC); however, Hb, leukocyte and platelet counts are not affected.  相似文献   
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