Factors revealed while posing mathematical modelling problems by mathematics student teachers

The purpose of this study is to reveal factors considered by mathematics student teachers while posing modelling problems. The participants were twenty-seven mathematics student teachers and posed their modelling problems within their groups. The data were obtained from the modelling problems posed by the participants, their solutions on these problems and the groups’ reflective diaries regarding their problem posing and solution processes. The data were analyzed by using content analysis and the codes were constructed according to the problems’ contents. The participants' diaries were examined in terms of generated codes and the expressions supporting/relating the codes were determined. While designing the problems, the participants considered the factors such as being interesting, understandable, appropriateness to real life and modelling process, model construction, and usability of different mathematical concepts. Their solutions were generally handled in terms of usage of the mathematical statements, appropriateness to the modelling process and being meaningful for real life. Modelling training should be provided to enable the student teachers to develop modelling problems and their designs should be examined and the feedbacks should be given. © 2018 Eurasian Society of Educational Research. All Rights Reserved

Aqua-toxicological Effects of Water Soluble Fractions (WSF) Of Diesel Fuel On O. Niloticus Fingerlings

Five concentrations of water soluble fraction (WSF) of diesel fuel (1.6 ppm, 3.2ppm, 6.4ppm, 12.3ppm and 19.2ppm) were made. To each of the concentrations of the WSF, ten fingerlings of O. niloticus with an average weight of 3g were incubated for 96hours. The 96hour LC50 was determined (8.08ppm). Histopathological examination of the fish gills following exposure to the LC50 and LC100 concentrations of the WSF showed gill elongation and lamellar hyperplasia respectively. There was reduction of dissolved oxygen content (from 7.2 to 4.5 mg/l) caused by diesel that dissolved in water. This was below acceptable levels for the sustenance of aquatic life (i.e. 6.0 - 8.0 mg/L). However, the pH reading was not adversely affected. The result tended to suggest that the death of the fingerlings might be related to the decreased dissolved oxygen content of the water due to the presence of diesel. The structural changes of the gills observed may be an adaptation by the fingerlings to oxygen stress. @JASE

Mathematics student teachers' modelling approaches while solving the designed Eşme Rug Problem

The purpose of the study is to analyze the mathematics student teachers' solutions on the Eşme Rug Problem through 7-stage mathematical modelling process. This problem was designed by the researchers by considering the modelling problems' main properties. The study was conducted with twenty one secondary mathematics student teachers. The data were collected from the participants' written solutions related to the problem. To analyze the students' answers through mathematical modelling process, the researchers compiled 7-stage mathematical modelling process from the literature. It was observed that the problem created an appropriate process for mathematical modelling. While examining the solutions of the participants who were informed about this 7-stage mathematical modelling process, it was generally observed that their solution approaches toward the problem decreased while progressing in modelling stages. © Authors

Halofantrine Hydrochloride (Halfan) Induced Toxicity of the Pancreas in Wistar Rats

The toxicity of halofantrine hydrochloride to the pancreas of wistar rats (Rattus norvegicus) was studied using twenty five male wistar rats divided into five groups of five rats per group. Group A (control group) was given only clean water. Groups B. C. D and E received 0.7; 1.4; 2.1 and 2. 8g/kg Body not of halofantrine hydrochloride administered orally every six hours for three times (complete dose) respectively. The results showed Odema and swelling of pancreatic acini cells and obliteration of interstitial spaces. This toxicity effect was found to be dose dependent and significantly different from the normal integrity of the cells observed in the control experiment: The result underscored a possible toxic effect halofantrine when administered into man. Based on the result obtained, there was need for caution on the use of halfan in the treatment of malaria, particularly in cases of drug abuse. It is suggested that further studies are required to elucidate the implication of this toxicity to both the endocrine and exocrine functions of the pancreas

Assessment of Psychophysiological Differences of West Point Cadets and Civilian Controls Immersed within a Virtual Environment

Abstract. An important question for ecologically valid virtual environments is whether cohort characteristics affect immersion. If a method for assessing a cer-tain neurocognitive capacity (e.g. attentional processing) is adapted to a cohort other than the one that was used for the initial normative distribution, data ob-tained in the new cohort may not be reflective of the neurocognitive capacity in question. We assessed the psychophysiological impact of different levels of immersion upon persons from two cohorts: 1) civilian university students; and 2) West Point Cadets. Cadets were found to have diminished startle eyeblink amplitude compared with civilians, which may reflect that cadets experienced less negative affect during the scenario in general. Further, heart rate data re-vealed that Cadets had significantly lower heart rates than Civilians in the “low ” but not “high ” immersion condition. This suggests that “low ” immersion conditions may not have the ecological validity necessary to evoke consistent affect across cohorts

Halofantrine Hydrochloride (Halfan) Induced Toxicity of the Pancreas in Wistar Rats

The toxicity of halofantrine hydrochloride to the pancreas of wistar rats (Rattus norvegicus) was studied using twenty five male wistar rats divided into five groups of five rats per group. Group A (control group) was given only clean water. Groups B. C. D and E received 0.7; 1.4; 2.1 and 2. 8g/kg Body not of halofantrine hydrochloride administered orally every six hours for three times (complete dose) respectively. The results showed Odema and swelling of pancreatic acini cells and obliteration of interstitial spaces. This toxicity effect was found to be dose dependent and significantly different from the normal integrity of the cells observed in the control experiment: The result underscored a possible toxic effect halofantrine when administered into man. Based on the result obtained, there was need for caution on the use of halfan in the treatment of malaria, particularly in cases of drug abuse. It is suggested that further studies are required to elucidate the implication of this toxicity to both the endocrine and exocrine functions of the pancreas

Examining of model eliciting activities developed by mathematics student teachers

The purpose of this study is to examine the model eliciting activities developed by the mathematics student teachers in the context of the principles of the model eliciting activities. The participants of the study conducted as a case study design were twenty one mathematics student teachers working on seven groups. The data collection tools were the developed model eliciting activities and semi-structured interviews. The model eliciting activities and the transcriptions of the interviews were deeply analyzed based on the principles. The results showed that while one group's activity was not a model eliciting activity, the ones of two groups were appropriate to the all principles. Other model eliciting activities were completely or partly appropriate to the principles. It was seen that the reality and model construction principles were binding role in developing these activities. The self-assessment and construct documentation principles were directly related to each other. The construct share ability and reusability, and effective prototype principles were the principles which were associated with the others and could be elicited effectively by tracking future implementations. © 2017 Journal on Mathematics Education. All rights reserved