Practical stability in terms of two measures for fractional order dynamic systems in Caputo's sense with initial time difference

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.     

当今我国政府有效性建设探索

在我国的社会经济发展过程中,政府的有效性建设是个事关全局的问题,它的妥善解决对于推动社会进步和经济发展具有不言自明的意义.文章试从政府的有效性概念入手,结合我国实际,指出了我国政府有效性建设的努力方向.     

A meta-analysis of the impact of mobile learning on mathematics achievement

Education and Information Technologies - The technological developments of the twenty-first century have enabled the emergence of alternative teaching-learning models and instructional tools. One...     

The mathematics teacher identity of two early career mathematics teachers and the influence of their working communities on its development

Journal of Mathematics Teacher Education - To better understand the critical early years of teaching and teacher identity development, this study explored the mathematics teacher identity of two...     

Algorithmic thinking development through physical computing activities with Arduino in STEM education

Education and Information Technologies - The need to benefit from information technologies in the twenty-first century digital age is increasing in all economies to overcome problems and...     

试论冯友兰教育哲学

冯友兰是哲学家,也是教育家,他的教育理念和教学实践以他的教育哲学为基础,其中人性论、境界论和创新论是他教育哲学的主要内容。从人性论出发,冯友兰认为人性既是伦理的也是理智的,所以培养学生要德智双修;从境界论出发,冯友兰着眼学生全面发展,注重提升学生的精神境界;从创新论出发,冯友兰认为教育的关键是培养学生的创新能力。     

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.     

Effect of a semi electro-mechanical engine valve on performance and emissions in a single cylinder spark ignited engine

In this study, an electro-mechanical valve （EMV） system for the intake valve ofa fottr stroke, single cylinder, overhead valve and spark ignition （SI） engine was designed and constructed. An engine with the EMV system and a standard engine were tested to observe the effects of the EMV on engine performance and emissions at different speeds under full load. The EMV engine showed improved engine power, engine torque and break specific fuel consumption （BSFC）. A 66% decrease in CO emissions was also obtained with the EMV system, but hydrocarbons （HC） and NOx emissions increased by 12% and 13% respectively.     

The Effect of Computer-Assisted Learning Integrated with Metacognitive Prompts on Students’ Affective Skills

The purpose of this study is to investigate the effect of computer-assisted learning integrated with metacognitive prompts on elementary students’ affective skills on the subject of electricity. The researchers developed educational software to enable students to easily and comprehensively learn the concepts in the subject of electricity. A case study method was used. Eighteen students from the seventh grade (12–13 years) participated in the study. Students’ views on their performances while using educational software and the impact of the software on their affective skills towards the subject of electricity were examined. Data were collected by open-ended questions in the educational software. According to the research results, there were students who had negative attitudes and perceptions before starting to learn about the subject of electricity. Interactive activities, animations, and visual experiments in the educational software were effective in overcoming the students’ negative attitudes and perceptions about the subject. Besides, students who assessed their own performances during the learning process believed themselves to be more successful over time. In the light of the research results, some suggestions are made for future studies.