Stability studies of common biochemical analytes in serum separator tubes with or without gel barrier subjected to various storage conditions

Introduction

The collected and shipped blood samples are exposed to a various extra-analytical factors prior to analysis. The aim of the study was to determine the stability of analytes in serum gel tubes and plain tubes exposed to a range of storage temperatures and times after centrifugation.

Materials and methods:

Fifteen healthy volunteers were recruited and venous blood was collected into four tubes, two with and two without gel separator. Analyzing the baseline samples in 30 min, all were stored at 4ºC or 24ºC for 6, 12, 18, 24, 30, 36, 48 and 72 hours and 1 week. Sixteen biochemical anaytes were measured on each sample. Variations remained under the desirable bias considered as clinically insignificant.

Results:

On day three, most analytes remained stable including albumin, protein, creatinine, cholesterol, triglycerides, gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), alanine aminotransferase (ALT), creatine kinase (CK), lactate dehydrogenase (LD) regardless of tube types. Glucose concentration decreased markedly (P = 0.001) beginning from the first hours of storage in plain serum. The stability maximized for the analytes including glucose, total bilirubin, urea nitrogen (BUN), uric acid stored at 4 ºC in gel tubes. Aspartate aminotransferase (AST) activity increased significantly (P = 0.002) up to 48-h, however bias was not significant clinically. High density lipoprotein (HDL) concentration was stable in gel tubes at 24 ºC, in plain tubes at 4 ºC stored up to 36-h.

Conclusion:

Serum gel or non-gel tubes might be used interchangeably for 11 analytes chilled or at 24 ºC, whereas some restrictions must be applied for glucose, AST, BUN, HDL, and uric acid.     

Chebyshev polynomial solutions of systems of higher-order linear Fredholm-Volterra integro-differential equations

A Chebyshev collocation method, an expansion method, has been proposed in order to solve the systems of higher-order linear integro-differential equations. This method transforms the IDE system and the given conditions into the matrix equations via Chebyshev collocation points. By merging these results, a new system which corresponds to a system of linear algebraic equations is obtained. The solution of this system yields the Chebyshev coefficients of the solution function. Some numerical results are also given to illustrate the efficiency of the method. Moreover, this method is valid for the systems of differential and integral equations.     

Autonomous and controlling reasons underlying achievement goals during task engagement: their relation to intrinsic motivation and cheating

The aim of this study was to investigate the relation of autonomous and controlling reasons underlying an endorsed achievement goal to intrinsic motivation and cheating. The endorsement of the achievement goal was ensured by involving 212 (M_age = 19.24, SD = .97) freshman students in a spatial task and asking them to report their most important achievement goal, as well as the reasons for adopting the goal, during the task. Results from a hierarchical regression analysis revealed that independent of the achievement goal the students adopted, the autonomous reasons for the endorsed goal were positively related to the indices of intrinsic motivation. Furthermore, the autonomous reasons underlying either performance or mastery-avoidance goals were negatively related to cheating. Alternatively, the controlling reasons for the endorsed goal were positively related to pressure and tension. The importance of considering both the ‘what’ and the ‘why’ aspect of achievement motivation are discussed.     

Mobile marketing research: The-state-of-the-art

Rapid proliferation in the business potential of mobile marketing attracts researchers from various fields to contribute to the growing body of knowledge on the phenomena. Although the literature on mobile marketing is accumulating, the stream of research is still in the development stage, hence is highly inconsistent and fragmented. This paper aims to organize and classify the literature on mobile marketing and assess the-state-of-the-art in order to facilitate future research. The review covers 255 peer-reviewed journal articles from 82 journals published between 2000 and 2008. The resulting framework summarizes the progress in mobile marketing research and provides future research directions.     

Visiting Shrines: A Turkish Religious Practice and Its Mental Health Implications

The purpose of the present study was to explore through qualitative methodology the practice of visiting shrines, a religious practice indigenous to Turkish Muslims, and its potential mental health benefits. Thirteen individuals were interviewed at two shrines in Istanbul, Turkey. The researchers focused on visitors’ presenting issues, beliefs regarding the practice, the mental health benefits of the visit, and the behaviors that the visitors engaged in during their visit. The data were analyzed using the Consensual Qualitative Research method. Five domains emerged from the data: (i) degree of religiosity and duties, (ii) knowledge and beliefs about shrines, (iii) purpose of visits, (iv) activities during the visit, and (v) experience and impact of the visit. The findings were discussed based on the mental health benefits of visiting shrines and the counseling and cultural implications.     

A professional development program for primary school English language teachers in Turkey: designing a materials bank

This paper presents and discusses an in-service teacher development program that focussed on establishing a materials bank for English language teachers at a private primary school in Ankara, Turkey, and teachers’ evaluations of the program. The program aimed to lead to teacher change as growth and learning, to address school-based needs, and to provide overall quality improvement. Feedback obtained during the professional development program and after its completion demonstrates that teachers improved their knowledge and skills on materials design and curriculum related issues as well as improving the overall quality of instruction and developing a positive attitude towards professional development.     

Student Participation in Higher Education Institutions in Turkey

After the 2001 meeting of the European Ministers of Education held in Prague, higher education institutions in Turkey took serious actions in order to implement the goals of the Bologna Declaration (1999). Arrangements made for the democratization of universities and student participation in the decision‐making process formed one of the predominant actions. The formal point of these arrangements – aimed at student involvement in the university governance process via Student Councils and their representatives, was prescribed by law and forced universities to comply with the process. The present research provides information about the legal arrangements in higher education institutions concerning student involvement in the university decision‐making process and the obstacles met within the course of application. In addition, it presents the findings of an empirical study related to student representation and involvement in governance through the agency of the Student Councils.     

Raising the language awareness of pre‐service English teachers in an EFL context

This study investigates the challenges that non‐native pre‐service English teachers (Haluk, Gaye, Selin, Öznur and Serkan) experience in their target language use when they do their practicum in actual language classrooms. This study found that the common difficulties the student teachers encounter related to certain grammatical structures, explaining unknown words to students, modifying language according to students’ level, and authenticity of the classroom language. During this study, the target language awareness training session was offered by the university supervisor in order to improve the student teachers’ target language use in the classroom. The training sessions included classroom observations, feedback sessions, semi‐structured interviews, retrospective protocols and discussion meetings with the student teachers. The findings indicated that the language awareness training had a positive impact on the target language use of the pre‐service English teachers. Furthermore, this study discusses the curriculum and the requirements of the language teacher education programme in an EFL setting and makes suggestions for the professional development of non‐native pre‐service language teachers.