Are All These Rules Necessary? Extension Pesticide Programming with a Regulatory Purpose

Indiana\u27s private applicator recertification program includes state-required, pesticide regulatory topics. This article explores the relationship between Indiana private applicators\u27 dual attitudes towards pesticide handling practices and the pesticide regulations that mandate those practices. Newly recertified private applicators in northwest Indiana were surveyed by a mailed questionnaire. Respondents valued responsible pesticide management practices, but were collectively undecided about regulatory oversight of their pesticide handling activities. These results suggest that Extension pesticide safety educators involved in compliance education may improve their training curriculum by including material on the underlying benefits, personal and social, of pesticide regulation

Uitdagend gedifferentieerd vakonderwijs:Praktisch gereedschap om je onderwijsrepertoire te blijven uitbreiden

Teaching and Teacher Learning (ICLON

STEM students’ career choice for teaching: studying career choice processes using personal projects

Understanding how teaching interest and motivation develop during the academic STEM (science, technology, engineering, and mathematics) study program is essential to design effective interventions to increase teacher recruitment. This article describes a new approach to study STEM teachers’ career choice processes. The retrospective method, which is based on personal projects analysis, focuses on the career choice process of STEM teachers during the academic study program as well as on their current personal values and goals, and the interconnection between these two. Evaluation took place in a small-scale explorative study with recently graduated STEM teachers. The results illustrate that the methodology provides insight into STEM teachers’ career choice processes in a personally salient and ecologically valid way. The use of personal projects provides structure and focus, but also enables large-scale data collection. Therefore, this research methodology could be positioned to complement survey studies and narrative inquiry.Teaching and Teacher Learning (ICLON

Skeletal ¹⁸F-PSMA-1007 uptake in prostate cancer patients

Background/objectives: Accurate and uniform interpretation and reporting of metastatic prostate cancer (PCa) lesions on prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) are indispensable. 18F-PSMA-1007 is increasingly used because of its favorable imaging characteristics. However, increased non-specific skeletal uptake may be an important pitfall of this radioligand. Therefore, we aimed to assess the interobserver variation in reporting skeletal 18F-PSMA-1007 uptake on PET/CT.Design/methods: In total, 33 18F-PSMA-1007 PET/CT scans of 21 patients with primary PCa and 12 patients with biochemical recurrence were included, and a total of 85 skeletal lesions were evaluated by three independent observers. The primary endpoint was the interobserver variability of the likelihood of malignancy of the skeletal lesions on both patient and lesion level (kappa analysis).Results: Observers qualified most lesions as not malignant (81–91%) and the overall mean interobserver agreement was moderate on both patient (κ: 0.54) and lesion level (κ: 0.55). In 52 lesions without corresponding CT substrate, the rating resulted in not malignant in 95–100%. Availability of additional imaging (60% of lesions) did not improve interobserver agreement (κ: 0.39 on lesion level) and resulted in unchanged rating for all observers in 78%.Conclusion: This interobserver analysis of skeletal 18F-PSMA-1007 uptake resulted in moderate agreement, in line with rates reported in literature. Importantly, the presence of non-specific skeletal uptake without CT substrate, as a potential shortcoming of 18F-PSMA-1007, did not impair interobserver agreement.</p

Fully Dynamic Numerical Simulation of the Hammer Peening Fatigue Life Improvement Technique

AbstractThis paper presents the results of the development process for a Finite Element Analysis of the Hammer Peening Fatigue Life Improvement Technique. The Fatigue Life of welded structures is still in need for improvement. The sheer number of Fatigue Live Improvement Techniques parameters leads to the need of simulating and predicting their results. For this study, two different materials were used, an Austenitic Stainless Steel and a Duplex Stainless Steel. Non-load carrying cruciform weld joints were produced and fatigue tested, with and without the Hammer Peening treatment. Finally a FEA code (ABAQUS®) was used to simulate the Hammer Peening technique. A fully dynamic model was used, combined with the Chaboche Kinematic-hardening material model and different Hammering parameter experimentally determined. Alongside the residual stresses introduced by the Hammer Peening Technique, the predicted Fatigue Life using the FEA model were compared with the experimental results, showing a very good agreement between them. Also the effect of several parameters, like the hammering impact load, the hammer positioning or the number of hammering passages, were analysed as a way to validate the FEA model. The most important result was of course the Fatigue Strength Gain factor, for the Hammer Peening Technique, that in both cases was found to be superior to 1.3

Promoting insight into algebraic formulas through graphing by hand

Student insight into algebraic formulas, including the ability to identify the structure of a formula and its components and to reason with and about formulas, is an issue in mathematics education. In this study, we investigated how 16- and 17-year-old pre-university students’ insight into algebraic formulas can be promoted through graphing formulas by hand. In an intervention of five 90-min lessons, 21 grade 11 students were taught to graph formulas by hand. The intervention’s design was based on experts’ strategies in graphing formulas, that is, using a combination of recognition and qualitative reasoning, and on principles of teaching complex skills. To assess the effect of this intervention, pre-, post-, and retention tests were administered, as well as a post-intervention questionnaire. Six students were asked to think aloud during the pre- and posttests. The results show that all students improved their abilities to graph formulas by hand. The think-aloud data suggest that the students improved both on recognition and reasoning, and give a detailed picture of how students used recognition and qualitative reasoning in combination. We conclude that graphing formulas by hand, based on the interplay of recognition and qualitative reasoning, might be a means to promote students’ insight into algebraic formulas