An optimum non-circular chainwheel design for a bicycle drive system

A new and systematic approach for the analysis and simulation of a non-circular chainwheel in a bicycle drive system is presented. The proposed leg-bicycle model is based on a five-bar linkage and explicit expressions for the kinematics and kinetics are derived. The generated shape of the chainwheel is smoothed to an ellipse, for practical reasons. The performance of this elliptical chainwheel is assessed by comparing the joint moments, leg angular accelerations, crank angular velocities, crank angular accelerations and output forces with those of a conventional circular chainwheel. The results suggest combining the elliptical and circular chainwheels into a single unit, in order to accommodate a wide range of pedalling speeds. At low speeds, the elliptical chainwheel is engaged, but as the speed increases, a switch over to the circular chainwheel is recommended.     

History of Spanish Mathematics Education Focusing on PhD Theses

This article offers an overview of mathematics education in Spain, analyzing the production of PhD theses over the last 30 years. This period has been divided into four cycles that describe the evolution of Spanish research in the field of mathematics education, together with changes in university and social politics. This paper also includes a forecast of the number of theses that will be produced over the next 7 years, thus predicting the future progress and development of this area of research.     

Attitudes of Australian chiropractic students toward whole body donation: A cross‐sectional study

Cadavers play an important role in anatomy education. In Australia, bodies for anatomy education are acquired only through donations. To gain insight into educational dynamics in an anatomy laboratory as well as to facilitate body donation programs and thanksgiving ceremonies, it is important to understand students' attitudes toward body donation. In this cross‐sectional study, the attitudes of Macquarie University's first, second, and fifth year chiropractic students toward body donation were investigated. Macquarie University chiropractic students have a four semester long anatomy program, which includes cadaver‐based instruction on prosected specimens. A questionnaire was used to record respondents' demographics and attitudes toward body donation: personal, by a relative, and by a stranger. It was found that ethnicity and religion affect attitudes toward body donation, with Australian students being more willing to donate a stranger's body and atheists and agnostics being more willing to donate in general. Furthermore, willingness to donate one's own or a family member's body decreases as year of study increases, suggesting a possible negative impact of exposure to cadavers in the anatomy laboratory. This was only true, however, after controlling for age. Thus, the impact of viewing and handling prosected specimens, which is the norm in anatomy classes in Australia, may not be as strong as dissecting cadavers. It is suggested that anatomists and educators prepare students for cadaver‐based instruction as well as exhibit sensitivity to cultural differences in how students approach working with cadavers, when informing different communities about body donation programs and in devising thanksgiving ceremonies. Anat Sci Educ 7: 117–123. © 2013 American Association of Anatomists.     

Phospholipid—polymer amphiphile hybrid assemblies and their interaction with macrophages

Recently, the combination of lipids and block copolymers has become an alternative to liposomes and polymersomes as nano-sized drug carriers. We synthesize novel block copolymers consisting of poly(cholesteryl acrylate) as the hydrophobic core and poly(N-isopropylacrylamide) (PNIPAAm) as the hydrophilic extensions. Their successful phospholipid-assisted assembly into vesicles is demonstrated using the evaporation-hydration method. The preserved thermo-responsive property of the lipid-polymer hybrids is shown by a temperature dependent adsorption behaviour of the vesicles to poly(l lysine) coated surfaces. As expected, the vesicle adsorption is found to be higher at elevated temperatures. The cellular uptake efficiency of hybrids is assessed using macrophages with applied shear stress. The amount of adhering macrophages is affected by the time and level of applied shear stress. Further, it is found that shorter PNIPAAm extensions lead to higher uptake of the assemblies by the macrophages with applied shear stress. No inherent cytotoxicity is observed at the tested conditions. Taken together, this first example of responsive lipid-polymer hybrids, and their positive biological evaluation makes them promising nano-sized drug carrier candidates.     

An Assessment of Pronouns as Linguistic Cues for Predicting Work Attitudes

Former Secretary of Labor Robert Reich (Reich, 1993) proposed that the pronouns employees use to describe their organization reveal information about their levels of engagement and affective commitment at work. In particular, he predicted that employees who describe their organization using the pronoun “we” are more engaged and committed than those who use the pronoun “they” in describing their organization. Reich's proposal has intuitive appeal and has been repeated in popular press accounts, but the accuracy of his prediction has not been empirically evaluated. In this article, we systematically examine the “Reich test” and find that the gender of the respondent is an important boundary condition to Reich's prediction. That is, our findings suggest that use of the pronoun “we” may serve as a predictor of work engagement and affective commitment for men, but not for women. We discuss the implications of these findings and the promise of exploring employees' linguistic indicators to understand social, affective, and cognitive psychological processes.     

Use of the MSJCC: A content analysis of ACA journals

Using quantitative content analysis, we examined the prevalence and use of the Multicultural Social Justice Counseling Competencies (MSJCC) in 21 ACA journals between June 2015 and July 2021. We found that only 7.62% of the articles (n = 2860) referenced the MSJCC. Implications for counselor educators are discussed.     

Contradictions in mathematical modeling with digital technologies

Education and Information Technologies - This article presents an analysis of contradictions expressed by pre-service mathematics teachers when performing two modeling tasks using their own...     

Understanding video as a tool for teacher education: investigating instructional strategies to promote reflection

There is a general consensus among researchers and teacher educators that classroom video can be a valuable tool for pre-service teacher education. Media such as video are not, however, in themselves effective. They have to be embedded in an instructional program to be useful. Yet, little empirical research examines how specific instructional approaches might effectively exploit the potential of video in teacher education. In this study we explored the use of two video-based university courses, one representing a cognitive instructional strategy integrating video, the other representing a situative strategy. Using data from learning journals we analyzed the effects of the two strategies on pre-service teachers’ (N = 28) ability to reflect on classroom video. We found that the two strategies have distinct impacts on the kinds of reflection patterns that are fostered. Our findings suggest that the learning goal and purpose at hand should determine which instructional strategy should be employed when embedding classroom video into teacher education courses.     

Attributional beliefs of Singapore students: relations to self-construal,competence and achievement goals

This study investigates attributional beliefs of Singapore secondary students in their English study and how they can be predicted by self-construal, competence and achievement goals. A total of 1,496 students were administered surveys on seven attributions, independent and interdependent self-construals, previous achievement, self-efficacy, mastery approach and avoidance goals and performance approach and avoidance goals. We found that Singapore students attributed academic success mainly to internal regulation (effort, interest and study skills), followed by teachers’ help, ability, parents’ help and tuition classes. Hierarchical regression analyses showed that three predictors (self-construal, competence and achievement goals) explained 4.2–12.3% of the variances in students’ attributional beliefs. In particular, students with interdependent self-construal, high competence or mastery goals tended to attribute academic success to internal regulation (effort, interest and study skills) and support from teachers and parents. Students with low competence, high mastery avoidance goals or high performance goals were more likely to value tuition classes, and those with high performance avoidance goals also tended to ascribe academic success to ability and parent’s help. The findings are discussed in relation to the culture of Singapore.     

Comparative education research framed by neo-institutional theory: a review of diverse approaches and conflicting assumptions

The rise in globalisation studies in comparative education places neo-institutional theory at the centre of many debates among comparative education researchers. However, uncertainty about how to interpret neo-institutional theory still persists among educational comparativists. With this uncertainty comes misinterpretation of its principles, variations and explanatory power. Two problematic misconceptions prevail: (1) the belief that the ‘world culture’ strand is the only version of neo-institutional theory applicable to comparative education research; and (2) the assumption that the global homogenisation of society, culture and schooling is a goal of researchers applying neo-institutional theory to comparative education phenomena. This article addresses these misconceptions, elucidating neo-institutional theory and its applicability to comparative education research. Our findings suggest that neo-institutional frameworks for comparative education research are useful, but that complementary approaches and methods are also necessary.