Beyond the beaker: students’ use of a scaffold to connect observations with the particle level in the organic chemistry laboratory

Author(s):  
Liz Keiner ◽  
Nicole Graulich

Understanding ongoing chemical processes in the laboratory requires constant shifting between different representational levels—the macroscopic, submicroscopic, and symbolic levels—and analysis of the various mechanistic features of each of these levels. Thus, the ability to explain observations of chemical phenomena with regard to their submicroscopic levels in the laboratory is a key requirement. Research shows that students have difficulty in discerning and comprehending the meaning and visualization of the submicroscopic level. Traditional laboratory instruction often fails to help students discern the relationship between their observations and the corresponding chemical processes. Consequently, there is a high demand for new teaching strategies which address these issues. Therefore, we developed and implemented a scaffold for the organic laboratory and tested it in a research study using qualitative methods. The scaffold encourages students to purposefully separate and connect the macroscopic and submicroscopic representational levels. The implementation of the scaffold was accompanied by semi-structured pre- and post-interviews with students (N = 22) and an analysis of students’ work with the scaffold in the laboratory. We analysed students’ sense-making approach while reflecting on organic syntheses before and after working with the scaffold, and characterized changes in their approach. The findings emphasize the need to develop further resources to support students’ understanding of the submicroscopic level. Implications of these findings for research and teaching to foster meaningful learning in the organic laboratory are discussed.

2012 ◽  
Vol 33 (2) ◽  
pp. 83-88 ◽  
Author(s):  
David Moreau ◽  
Jérome Clerc ◽  
Annie Mansy-Dannay ◽  
Alain Guerrien

This experiment investigated the relationship between mental rotation and sport training. Undergraduate university students (n = 62) completed the Mental Rotation Test ( Vandenberg & Kuse, 1978 ), before and after a 10-month training in two different sports, which either involved extensive mental rotation ability (wrestling group) or did not (running group). Both groups showed comparable results in the pretest, but the wrestling group outperformed the running group in the posttest. As expected from previous studies, males outperformed women in the pretest and the posttest. Besides, self-reported data gathered after both sessions indicated an increase in adaptive strategies following training in wrestling, but not subsequent to training in running. These findings demonstrate the significant effect of training in particular sports on mental rotation performance, thus showing consistency with the notion of cognitive plasticity induced from motor training involving manipulation of spatial representations. They are discussed within an embodied cognition framework.


2020 ◽  
Vol 22 (3) ◽  
pp. 341-361
Author(s):  
Gonzalo Grau-Pérez ◽  
J. Guillermo Milán

In Uruguay, Lacanian ideas arrived in the 1960s, into a context of Kleinian hegemony. Adopting a discursive approach, this study researched the initial reception of these ideas and its effects on clinical practices. We gathered a corpus of discursive data from clinical cases and theoretical-doctrinal articles (from the 1960s, 1970s and 1980s). In order to examine the effects of Lacanian ideas, we analysed the difference in the way of interpreting the clinical material before and after Lacan's reception. The results of this research illuminate some epistemological problems of psychoanalysis, especially the relationship between theory and clinical practice.


2016 ◽  
Vol 045 (06) ◽  
Author(s):  
Eleanor Sterling ◽  
Adriana Bravo ◽  
Ana Luz Porzecanski ◽  
Romi Burks ◽  
Joshua Linder ◽  
...  

2020 ◽  
Author(s):  
William J. Howitz ◽  
Kate J. McKnelly ◽  
Renee Link

<p>Large, multi-section laboratory courses are particularly challenging when managing grading with as many as 35 teaching assistants (TAs). Traditional grading systems using point-based rubrics lead to significant variations in how individual TAs grade, which necessitates the use of curving across laboratory sections. Final grade uncertainty perpetuates student anxieties and disincentivizes a collaborative learning environment, so we adopted an alternative grading system, called specifications grading. In this system each student knows exactly what level of proficiency they must demonstrate to earn their desired course grade. Higher grades require demonstrating mastery of skills and content at defined higher levels. Each students’ grade is solely dependent on the work they produce rather than the performance of other students. We piloted specifications grading in the smaller, third quarter course of the lower division organic chemistry laboratory series held during a summer term. Open-ended questions were chosen to gather student and TA perceptions of the new grading system. TAs felt that the new grading system reduced the weekly grading time because it was less ambiguous. Responses from students about the nature of the grading system were mixed. Their perceptions indicate that initial buy-in and multiple reminders about the bigger picture of the grading system will be essential to the success of this grading system on a larger scale.</p>


2017 ◽  
pp. 119-124
Author(s):  

Introduction: Intestinal parasite infections werecommonintropical country such as Vietnam. Having good knowledge of parasitic infectious prevention and changing risk behaviors can decrease the infection rate. Objective: To evaluate the parasitic infectious rate in Vinh Thai community before and after being health education and the changing of knowledge of parasitic infectious prevention and risk behaviors. Materials and methods: 60 households in Vinh Thai commune were interviewed their knowledge of parasitic infectious prevention and examined intestinal parasite infection by Kato technique and then trained the knowledge of parasitic infectious prevention. The interview and examination parasite infectiousrate were carried out after 6 months to evaluating their knowledge. Result: Before health education, the rate of intestinal parasite infection was 17.4% with the prevalence of Ascaris lumbricoides, hookworm, whipworm, pinworm, small fluke worm and co-infection with A. lumbricoides - whipworm, hookworm-whipworm were 0.1%; 8.0%; 5.8%; 0.6%; 0.3%; 1.2% and 3.0% respectively. Six months later the rate of intestinal parasite infection was decreased in 12.6% even though not statistical significantly. However, there were no case of small fluke worm and co-infection with hookworm-whipworm. Receiving health education, their knowledge of parasitic infectious prevention was higher significantly but their risk behaviors were not changed so much. Conclusion: Health education can change the rate of parasite infection with higher knowledge of parasitic infectious prevention but it was necessary continuous study to change the risk behaviors. Key words: intestinal parasite, health education


2018 ◽  
Vol 69 (05) ◽  
pp. 381-389
Author(s):  
MENGÜÇ GAMZE SÜPÜREN ◽  
TEMEL EMRAH ◽  
BOZDOĞAN FARUK

This study was designed to explore the relationship between sunlight exposure and the mechanical properties of paragliding fabrics which have different colors, densities, yarn counts, and coating materials. This study exposed 5 different colors of paragliding fabrics (red, turquoise, dark blue, orange, and white) to intense sunlight for 150 hours during the summer from 9:00 a.m. to 3:00 p.m. for 5 days a week for 5 weeks. Before and after the UV radiation aging process, the air permeability, tensile strength, tear strength, and bursting strength tests were performed. Test results were also evaluated using statistical methods. According to the results, the fading of the turquoise fabric was found to be the highest among the studied fabrics. It was determined that there is a significant decrease in the mechanical properties of the fabrics after sunlight exposure. After aging, the fabrics become considerably weaker in the case of mechanical properties due to the degradation in both the dyestuff and macromolecular structure of the fiber


Author(s):  
P.A. Popov ◽  
◽  
D.V. Gruznov ◽  
S.V. Tokarev ◽  
◽  
...  

The article presents the results of determining the relationship between the total microbial number and microbial ATP on the surface of milking equipment before and after treatment with neutral anolyte ANK-SUPER. The possibility of using the ATP-bioluminescence method to control the quality of sanitation of milking equipment on dairy farms is shown. Laboratory studies revealed a proportional relationship between the level of bacterial ATP and the number of bacteria on the surface of milking equipment before and after sanitation.


Sensors ◽  
2021 ◽  
Vol 21 (15) ◽  
pp. 4997
Author(s):  
Victor C. Le ◽  
Monica L. H. Jones ◽  
Kathleen H. Sienko

Postural sway has been demonstrated to increase following exposure to different types of motion. However, limited prior studies have investigated the relationship between exposure to normative on-road driving conditions and standing balance following the exposure. The purpose of this on-road study was to quantify the effect of vehicle motion and task performance on passengers’ post-drive standing balance performance. In this study, trunk-based kinematic data were captured while participants performed a series of balance exercises before and after an on-road driving session in real-time traffic. Postural sway for all balance exercises increased following the driving session. Performing a series of ecologically relevant visual-based tasks led to increases in most post-drive balance metrics such as sway position and velocity. However, the post-drive changes following the driving session with a task were not significantly different compared to changes observed following the driving session without a task. The post-drive standing balance performance changes observed in this study may increase vulnerable users’ risk of falling. Wearable sensors offer an opportunity to monitor postural sway following in-vehicle exposures.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Brianna L. Martinez ◽  
Ryan D. Sweeder ◽  
Jessica R. VandenPlas ◽  
Deborah G. Herrington

Abstract Background Engagement with particle-level simulations can help students visualize the motion and interactions of gas particles, thus helping them develop a more scientifically accurate mental model. Such engagement outside of class prior to formal instruction can help meet the needs of students from diverse backgrounds and provide instructors with a common experience upon which to build with further instruction. Yet, even with well-designed scaffolds, students may not attend to the most salient aspects of the simulation. In this case, a screencast where an instructor provides narrated use of the simulation and points students towards the important observations may provide additional benefits. This study, which is part of the larger ChemSims project, investigates the use of simulations and screencasts to support students’ developing understanding of gas properties by examining student learning gains. Results This study indicates that both students manipulating the simulation on their own and those observing a screencast exhibited significant learning gains from pre- to post-assessment. However, students who observed the screencast were more than twice as likely to transition from a macroscopic explanation to a particle-level explanation of gas behavior in answering matched pre- and post-test questions. Eye-tracking studies indicated very similar viewing and usage patterns for both groups of students overall, including when using the simulation to answer follow-up questions. Conclusion Significant learning gains by both groups across all learning objectives indicate that either scaffolded screencast or simulation assignments can be used to support student understanding of gas particle behavior and serve as a first experience upon which to build subsequent instruction. There is some indication that the initial use of the screencast may better help students build correct mental models of gas particle behavior. Further, for this simulation, watching the instructor manipulate the simulation in the screencast allowed students to subsequently use the simulation on their own at a level comparable to those students who had manipulated the simulation on their own throughout the assignment, suggesting that the screencast students were not disadvantaged by not initially manipulating the simulation on their own.


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