“Where Your Ethnic Kids Go”: How Counselors as First Responders Legitimate Proper Course Placements for Community College Students

ABSTRACT

Previous research on remediation has examined course placement practices, but little is known about first responders and how their beliefs about proper course placements help maintain patterns in course access. This study examined how taken-for-granted racial beliefs were used as legitimate knowledge by community college counselors. Haney López’s (2000) race as commonsense theoretical perspective was used to analyze interview data from 34 counselors in 2 southern California community colleges. Data showed that counselors recreated race categories and racial hierarchy, and they did so by reinforcing beliefs about white students as intelligent and deserving higher placements and Latina/o students as comparatively lower in ability and deserving remediation. The results suggest that counselors begin institutionalizing racial sorting immediately as first-time students begin to enroll. The findings highlight the importance of racial mindfulness in policy, practice, and research.     

“Did you do your homework?” Mathematics teachers’ homework follow‐up practices at middle school level

Teachers’ homework follow‐up practices, the in‐class strategies teachers use to monitor their students’ homework assignments, have an impact on their students’ homework behaviors and academic achievement. The current study explored the perspectives of middle school mathematics teachers on the three domains of homework follow‐up: the practices used in class, the purposes of each practice, and the aspects that may influence this process. Data were collected from two data sources (i.e., focus groups and classroom observations) and were analyzed using thematic analysis. The findings showed that teachers monitored homework either using a single strategy or a combination of strategies (e.g., checking homework completion and providing individual feedback) linked to a specific purpose (e.g., promote students’ involvement). The teachers also reported that they were under certain constraints when they delivered homework follow‐up practices (e.g., pressure to follow the curriculum), so their practices’ effectiveness sometimes can be compromised. Implications for practice are discussed.     

Probing transient protein-mediated DNA linkages using nanoconfinement

We present an analytic technique for probing protein-catalyzed transient DNA loops that is based on nanofluidic channels. In these nanochannels, DNA is forced in a linear configuration that makes loops appear as folds whose size can easily be quantified. Using this technique, we study the interaction between T4 DNA ligase and DNA. We find that T4 DNA ligase binding changes the physical characteristics of the DNA polymer, in particular persistence length and effective width. We find that the rate of DNA fold unrolling is significantly reduced when T4 DNA ligase and ATP are applied to bare DNA. Together with evidence of T4 DNA ligase bridging two different segments of DNA based on AFM imaging, we thus conclude that ligase can transiently stabilize folded DNA configurations by coordinating genetically distant DNA stretches.     

Floating-electrode enhanced constriction dielectrophoresis for biomolecular trapping in physiological media of high conductivity

We present an electrokinetic framework for designing insulator constriction-based dielectrophoresis devices with enhanced ability to trap nanoscale biomolecules in physiological media of high conductivity, through coupling short-range dielectrophoresis forces with long-range electrothermal flow. While a 500-fold constriction enables field focusing sufficient to trap nanoscale biomolecules by dielectrophoresis, the extent of this high-field region is enhanced through coupling the constriction to an electrically floating sensor electrode at the constriction floor. However, the enhanced localized fields due to the constriction and enhanced current within saline media of high conductivity (1 S/m) cause a rise in temperature due to Joule heating, resulting in a hotspot region midway within the channel depth at the constriction center, with temperatures of ∼8°–10°K above the ambient. While the resulting vortices from electrothermal flow are directed away from the hotspot region to oppose dielectrophoretic trapping, they also cause a downward and inward flow towards the electrode edges at the constriction floor. This assists biomolecular trapping at the sensor electrode through enabling long-range fluid sampling as well as through localized stirring by fluid circulation in its vicinity.     

Plato, Pascal, and the dynamics of personal knowledge

Abstract educational practices are to be based on proven scientific knowledge, not least because the function science has to perform in human culture consists of unifying practical skills and general beliefs, the episteme and the techne (Amsterdamski, 1975, pp. 43–44). Now, modern societies first of all presuppose regular and standardized ways of organizing both our concepts and our institutions. The explanatory schemata resulting from this standardization tend to destroy individualism and enchantment. But mathematics education is in fact the only place in which to treat the human subject’s relationship with mathematics. And that is what mathematics education is all about: make the human subject grow intellectually and as a person by means of mathematics. At first sight, mathematics, in its formal guise, seems the opposite of philosophy, because philosophy constructs concepts (meanings), whereas mathematics deals with extensions of concepts (sets). We shall, however, turn this problem into an instrument, using the complementarity of intensions and extensions of theoretical terms as our main device for discussing the relationship between philosophy and mathematics education. The complementarity of the “how” and the “what” of our representations outlines, in fact, the terrain on which epistemology and education are to meet.