Examination of Changes in Prospective Elementary Teachers’ Epistemological Beliefs in Science and Exploration of Factors Meditating That Change

Epistemological beliefs refer to an individual’s thinking and beliefs about the nature of knowledge and knowing. The present study examined two research questions: (1) how do prospective elementary teachers’ epistemological beliefs in science change as a result of instruction specifically designed to improve their epistemological beliefs and (2) what role does the conceptual ecology for epistemological beliefs play in their development? The study was correlational with a sample of 161 prospective elementary teachers (148 female, 13 male). Self-report questionnaires tapping four dimensions of epistemological beliefs (certainty-simplicity, justification, source, attainability of truth) were given to prospective elementary teachers at two time points during an introductory science course. Results indicated that prospective elementary teachers became more sophisticated in their beliefs across all four dimensions of epistemological beliefs. It was found that one component of conceptual ecology for epistemological beliefs, thinking dispositions, was related to the development of epistemological beliefs. Prospective teachers with high thinking dispositions developed more sophisticated beliefs in comparison to prospective teachers with low thinking dispositions.     

Effects of specimen haemolysis on complete blood count results by Abbott Alinity hq System

IntroductionThe current study aimed to assess the interference of in vitro haemolysis on complete blood count (CBC) using Abbott Alinity hq system, and to determine which haemolysis levels affect the reliability of sample results.Materials and methodsBlood samples obtained from 25 volunteers in K3-EDTA tubes were divided into four aliquots. The first aliquot was not subjected to any intervention. The second, third and fourth aliquots were passed through a fine needle 2, 4 and 6 times, respectively. Complete blood count was performed by multi-angle polarized scatter separation technology and haemolysis index (HI) was assessed from the plasma samples separated by centrifugation. Five groups were formed according to the HI values. The percentage biases between the results of non-haemolysed and haemolysed groups were compared with the desirable bias limits from The European Federation of Clinical Chemistry and Laboratory Medicine database and reference change values (RCVs).ResultsIn groups 1 to 4, the effects of haemolysis on CBC parameters were acceptable comparing to the analytical bias except for lymphocytes (7.26%-7.42%), MCH (2.59%), and MCHC (0.47%-2.81%). Results of group 5 (gross haemolysis) showed decreases in HCT(- 4.56%), RBC (- 4.07%) count and increase in lymphocyte (11.60%) count higher than the analytical performance specifications. Moreover, variations in MCH (4.65%) and MCHC (5.24%) were exceeding the RCVs.ConclusionsGross haemolysis (haemoglobin concentration > 10 g/L) is likely to produce unreliable CBC results on non-pathological samples. Further studies including pathological specimens are needed.