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71.

Introduction

Measurements of blood ethanol concentrations must be accurate and reliable. The most important factors affecting blood ethanol stability are temperature and storage time. In this study, we aimed to compare ethanol stability in plasma samples at -20 °C for the different storage periods.

Materials and methods

Blood samples were collected from intoxicated drivers (N = 80) and initial plasma ethanol concentrations were measured immediately. Plasma samples were then stored at -20 °C and re-assessed after 2, 3, 4, or 5 months of storage. Differences between the initial and stored ethanol concentrations in each group (N = 20) were analyzed using Wilcoxon matched-pairs test. The deviation from the initial concentration was calculated and compared with Clinical Laboratory Improvement Amendments (CLIA’88) Proficiency Testing Limits. Relationships between the initial concentrations and deviations from initial concentrations were analyzed by Spearman’s correlation analysis. For all statistical tests, differences with P values of less than 0.05 were considered statistically significant.

Results

Statistically significant differences were observed between the initial and poststorage ethanol concentrations in the overall sample group (P < 0.001). However, for the individual storage duration groups, analytically significant decreases were observed only for samples stored for 5 months, deviations from the initial concentrations exceeded the allowable total error (TEa). Ethanol decreases in the other groups did not exceed the TEa.

Conclusion

According to our results, plasma ethanol samples can be kept at -20 °C for up to 3-4 months until re-analysis. However, each laboratory should also establish its own work-flow rules and criterion for reliable ethanol measurement in forensic cases.Key words: preanalytical phase, ethanol, stability, storage temperature  相似文献   
72.
Due to the pandemic conditions, hands-on courses in architectural education were conducted remotely and their presentation had to be reconsidered. Hands-on courses, by their nature, support learning and learner-instructor interaction in the classroom environment. It was necessary to develop innovative solutions to ensure this interaction in virtual classrooms. This study discusses a method we experienced in the 2021–2022 spring semester of the “Principles of Digital Design and Fabrication in Architecture” course given at Gazi University. To combat potential interaction deficits, “problem-based learning (PBL)” and “learning by doing (LBD)” teaching methods were applied. While reflecting on foreseen problems in the curriculum on the students, we determined the distance education process causes different reflections on students in terms of digital modelling and fabrication techniques. All constraints and problem determinations obtained by the students were classified and a way to solve these problems developed with the LBD style. By the end of the course, the students, who were expected to design a small 3D object, first designed the mould then realised their fabrication of the object. In this process, while the foreseen problems and curriculum determined at the beginning overlapped, other problem determinations and their reflections formed an important base for the future curriculum.  相似文献   
73.
Education and Information Technologies - This study aims to explore kindergarten student teachers’ readiness to integrate technology into their future classrooms and factors affect their...  相似文献   
74.
A short 12-item version of the Career Adapt-Abilities Scale–Short Form (CAAS-SF) was validated across three different age groups in the Turkish context. Scale scores demonstrated adequate to high internal consistency and 4-week test–retest reliability, good fit with the original four-factor model, factorial invariance across gender and age groups, strong convergence with the 24-item version, negative associations with trait anxiety and work stress, and positive associations with career decision self-efficacy. It was concluded that the Turkish version of the CAAS-SF appears to be a valid and reliable measure for assessing career adaptability and using it in career education and counseling process.  相似文献   
75.
This study aimed to develop a rubric to assess participation of students in online discussion environments. For this purpose, the study included 168 students who participated in a course offered online during the spring semester of the 2015–2016 academic year. Developed based on the literature, the rubric consists of two parts (Form and Content, and Number and Density) and seven criteria in total. “Form and Content” consists of congruity of the message in terms of subject, clarity of the message, original value of the message, interactional value of the message, and directing the subject; whereas, “Number and Density” consists of the number of messages and their density. Four different discussion subjects were presented to the students in an online discussion environment. The researchers analyzed the students’ messages individually. Exploratory Factor Analysis was performed in order to obtain evidence for construct validity. After conducting the factor analysis, results showed that the first dimension, which is “form and content” sub-factor, is unidimensional. The “number and density” sub-factor was included in the graded scoring key based on the literature and expert opinion. The findings show that the graded scoring key is reliable and valid.  相似文献   
76.
The purpose of this study was to examine the correlation of different variables with information retention in guided 3D virtual learning environments by employing three experimental designs. In each experiments, different participants were included in the same population and different variables were considered. Information retention test, flow, presence, engagement scales were used as data collection tools. Namely measures of flow, presence and engagement were examined to see their correlation with retention in experiment 1, 2 and 3. As a result, not the total score of flow but focused attention, enjoyment and skill dimensions has a weak but significant correlation with information retention, while the challenge has a moderate and significant negative correlation. In the second experiment, retention had a significant, low-level relationship with teaching presence and cognitive presence, but it did not have a similar relationship with social presence. In the third experiment, information retention significantly correlated with affective and cognitive engagement, but not with behavioral engagement. Although the three studies’ participants were from the same population, It was seen that the differences in the level of relationship between information retention and the variables studied in each study. Nevertheless, it was found that the levels of flow, presence and engagement of students are important for information retention in a guided 3D virtual learning environment. The study is thought to guide researchers to design 3D virtual learning environments for different purposes, considering these variables.  相似文献   
77.
Math is a subject in which students are generally not very interested and are unsuccessful compared to other courses. It has been suggested that digital stories designed for educational purposes could be used to prevent students’ lack of interest and failure in this subject. However, designing stories that are fit for purpose is important if the use of digital stories is to be successful. The purpose of this study is to investigate pre-service teachers’ opinions about how they utilized the steps of Gagne’s model while designing digital stories for math lessons. The participants in the study were 49 pre-service teachers studying at a Math Department at a Turkish state university in the spring term of the 2014–2015 academic year. The Pre-service Teachers’ Opinion Form and a Personal Information Form, both developed by the researchers, were used as data collection tools in the study, in which the qualitative method was adopted. Content analysis was utilized to analyze the data collected through open-ended questions. When the findings were examined it was seen that pre-service teachers had designed digital stories in which they often chose to attract attention by creating interesting characters in the “gaining students’ attention” step of Gagne’s teaching model, that the main character stated the objectives/topic in the story precisely in the “informing students of the objectives” step, and that the characters created repeated the previous topic in the “stimulating recall of prior learning” step. In the current study, the integration of digital story design into lesson plans in accordance with Gagne’s model was carried out and pre-service teachers’ opinions about their experiences of this process were investigated.  相似文献   
78.
Objective: The major aim was to describe parental attitudes to physical punishments and examine their sociodemographic correlates. A related aim was to assess the association of parents’ own experience of physical punishment with attitudes to punishment of children.Method: A cross-sectional survey was conducted during the second week of December, 1996 in five general clinics covering the major administrative areas of Kuwait: 337 Kuwaiti mothers and fathers with at least one living child were contacted; 95% were successfully interviewed using a structured questionnaire.Results: Eighty-six percent of parents agreed with physical punishment as a means of child disciplining. Agreement with punishment was higher in case of serious misbehaviors such as stealing (63%), sniffing glue and using drugs (77%). Multiple regression results showed that parent’s lower level of education and Bedouin ethnicity were positively associated with agreement on physical punishment. Larger percentages of parents who had experienced physical punishments themselves agreed with such punishment to discipline their children, but this was not statistically significant.Conclusions: In recent years education has become widespread for both sexes. An inverse association between educational level and agreement on physical beating suggest that attitudes to this form of child disciplining are changing. Those with a Bedouin ethnic background still adhere more strictly to the traditional forms of child disciplining including physical beating. There is a need for conducting research on the possible negative psychosocial impacts of physical punishment in view of findings from other countries.  相似文献   
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