Identifying Science Teachers' Needs About Developing Students' Scientific Reasoning Skills

The aim of this study is to determine science teachers' needs about developing students' scientific reasoning skills. The study was qualitative descriptive survey and participants were 32 science teachers working at state middle schools with different socio-economic status in Izmir Data were collected via Needs Determination Survey developed by researchers. Content validity of survey was provided by expert views. Data obtained from survey were analyzed by using content analysis. At the end of the study, findings showed that teachers associated scientific reasoning skills with science process skills mostly; although they knew the place of scientific reasoning skills in the curriculum, they could not make any explanations about them; they could not design a scientific reasoning skills based learning environment due to the lack of their inadequacy and to overcome this, they needed some factors related to them such as training and colleague support and external factors such as enough experimental material and class size and they had an expectancy from a possible training to experience activities which they could use directly in the class and in which simple and cheap materials were used. It is hoped that this need analysis may contribute to other stakeholders to design training programs

Translation and Psychometric Evaluation of the Turkish Version of the Motivation to Change Lifestyle for Dementia Risk Reduction Scale (T-MOCHAD-10)

Background and Objectives: The number of people living with dementia is increasing globally, particularly in middle-income countries like Turkey. To reduce risk of dementia, the implementa-tion of lifestyle changes targeting modifiable risk factors are important. This study aimed to translate and validate the Turkish version of the Motivation to Change Lifestyle for Dementia Risk Reduction (T-MOCHAD-10).Methods: Cross-sectional psychometric study design was used. After translation and back trans-lation, we assessed face and content validity. For construct validation and reliability assessment, we conducted a survey with 601 individuals aged 40 and above using a socio-demographic form and the T-MOCHAD-10. We used Exploratory Principal Axis Factoring with Oblimin rotation to explore the factor structure. We then confirmed the factor structure using fit indices. Reliability was established using test-re-test, Cronbach's alpha coefficient, item-total and item-subdimen-sions correlations, ceiling and floor effects, and the Hotelling's T-squared test.Results: The T-MOCHAD-10 showed adequate face and content validity (Kendall W=0.09, p=0.60). As in the original scale, a two-factor solution was obtained. All fit indices were >= 0.95, and RMSEA was 0.06. A Cronbach's alpha of 0.79 was obtained and no significant differences were found between test and re-test measures (p>0.05). We found no evidence of ceiling or floor effects, nor response bias (Hotelling's T-squared=4683.80, p<0.001)

Improving the flame retardancy properties of PLA/PC blends

Polylactic acid/Polycarbonate (PLA/PC) blend was prepared via twin screw extruder by taking the bio-based content as much as possible and the better mechanical, thermal, and impact properties into consideration. Flame retardant (FR) performance of the PLA/PC blend was improved by using the mixture of ammonium polyphosphate, triphenyl phosphate, and zinc borate. FR properties of PLA/PC blend was evaluated according to the UL 94 test standard. The variations in tensile and flexural strength, and Izod-notched impact strength values were determined. In order to reduce the total amount of flame retardant additive, instead of using a mixture of TPP and APP (weight ratio of 2/1) at 21 wt% weight fraction, 1 wt% Zinc borate together with 18 wt% TPP-APP mixture was used and obtained V0 rating for the thickness of 1.5 mm. It was reported that weight fraction of flame retardant additives (APP and TPP) was successfully reduced by using a mixture of APP, TPP and ZnB without degrading the mechanical properties such as tensile and flexural strengths. Using less total FR additive weight (19 wt%) led to 15 and 24% higher tensile and flexural strength values, respectively, compared to higher FR additive weight (21 wt%)

The Evaluation of "Technological Pedagogical Content Knowledge based Argumentation Practices" Training for Science Teachers

In science education, creating learning environments supported with technology and students' use of theory-evidence coordination when expressing their ideas is emphasized regarding the development of students' scientific reasoning, critical thinking, decision making skills, and etc. In this process, great responsibilities are fallen to teachers as planner and designer of a learning environment. In this study, it is aimed to assess the training which aims the development of science teachers' technological pedagogical content knowledge (TPACK) through argumentation practices. In this context; this study evaluated the science teachers' argumentation skills, self-efficacy perceptions towards TPACK and the teachers' views about the training. 37 science teachers working at different cities in Turkey participated in the one group pre-test post-test experimental training study, which was lasted 54 hours during a week. The training is composed of both hand and minds on argumentation practices based on TPACK. The participants joined different activities such as collaborative group works, drama, modeling, thematic games, art activities, problem-based learning, field trips, observation and workshops. In the study, Argumentation Test, TPACK Self Efficacy Belief Scale were used as data collection tools. At the end of the training written views of science teachers towards activities were taken. In the light of the findings, this training was effective on the participants' self-efficacy levels towards technological pedagogical content knowledge. Moreover, this training resulted in a positive change in the participants' views about how a statement could be accepted as an argument. However, the increase in scores of argumentation skills was not significant. Additionally almost all of the participants stated that they found the activities useful and can use in their classes. By considering these results, some suggestions were given

Investigation of the Fire Performance of Polyamide 6-Based Composites with Halogen-free Flame Retardants and Synergistic Materials

In this study, halogen-free flame retardants and metal synergist materials were used to enhance the flammability of PA6. PA6-based composites including various fractions of additives were manufactured using a twin-screw extruder and an injection molding machine. Mechanical, thermal, physical, morphological, and flame retardant properties were investigated with several characterization methods. The study aims to meet R22 requirements based on the EN45545 standard for fire protection of railway vehicles, according to which limiting oxygen index (LOI), smoke density, and conventional index of toxicity (CIT) values under HL3 hazard levels have to be min 32%, max 300, and max 1.5, respectively. 15FR-2MH, 15FR-5MH, 15FR-1MH-1ZB, 15FR-1MH-1BOH, and 15FR-1MH-1SIL composites exhibited both the required smoke density, CIT, and LOI values for R22. It can be said that hybrid synergists provide all requirements according to the R22-EN45545 standard . Instead of using 15FR-2MH, 15FR-1MH-1BOH led to a lower smoke density value for PA6

Melatonin Modulates NMDA-Receptor 2B/Calpain-1/ Caspase-12 Pathways in Rat Brain After Long Time Exposure to GSM Radiation.

To investigate the potential protective effects of melatonin on the chronic radiation emitted by third generation mobile phones on the brain