Exploring teachers’ beliefs and feelings about race and police violence

ABSTRACT

In this article, the authors analyzed White teachers’ open-ended responses to three critical items on the Teachers’ Race Talk Survey (TRTS). The authors focused on: (1) teachers’ beliefs about the importance of discussing race in the classroom with their students; (2) teachers’ feelings of preparedness to have race conversations in the classroom with their students; and (3) teachers’ beliefs about discussing, in class, police violence against Black people. Findings showed that while most White teachers believed race was important to discuss in order to unlearn and disrupt their prior beliefs, the majority described fear as a primary factor for feeling unprepared to actually discuss race in the classroom. Despite their beliefs about the importance of race, teachers’ beliefs about police violence against Black bodies reflect a color-blind approach by either viewing police violence as a natural occurrence or minimizing the role that race plays. To continue developing teachers’ critical knowledge related to race, the authors discuss implications for examining the quality of race-centered curriculum in teacher education programs and they pose broader questions related to the evolving knowledge base for teaching.     

Self-Efficacy Beliefs,Classroom Management,and the Cradle-to-Prison Pipeline

In this article, we focus on connections between and among teachers’ self-efficacy beliefs, classroom management practices, and the cradle to prison pipeline. Drawing from Bandura’s (1986) theorization of self-efficacy, we discuss how teachers’ beliefs shape their classroom management practices and how these beliefs and practices can be essential sites to understanding and decreasing disparate outcomes in disciplinary referral patterns among practicing teachers. We emphasize the importance of building teachers’ self-efficacy beliefs and sense of efficacy to inform their classroom management practices/decisions. In particular, we focus on three sites of learning that, we argue, are essential to building teachers’ sense of efficacy in the classroom: learning about and building powerful and sustainable relationships with students; learning about and developing an understanding of outside of school contexts that students experience; and recognizing and appropriately responding to traumatic experiences of students.     

Diversity of Students' Views about Evidence,Theory, and the Interface between Science and Religion in an Astronomy Course

Arguments for teaching about the nature of science have been made for several decades. The most recent science education policy documents continue to assert the need for students to understand the nature of science. However, little research actually explores how students develop these understandings in the context of a specific course. We examine the growth in students' understanding about the nature of astronomy in a one‐semester college course. In addition to student work collected for 340 students in the course, we also interviewed focus students three times during the course. In this article we briefly describe class data and discuss in detail how five students developed their ideas throughout the course. In particular, we show the ways in which students respond to instruction with respect to the extent to which they (a) demand and examine evidence used for justifying claims, (b) integrate scientific and religious views, and (c) distinguish between scientific and nonscientific theories. © 2000 John Wiley & Sons, Inc. J Res Sci Teach 37: 340–362, 2000.     

Language,culture and border lives: mestizaje as positionality / Lengua,cultura y vidas de frontera: el mestizaje como posicionalidad

Recent scholarly work has focused on borders, both geopolitical and cultural, giving attention to border lives and identities. This article, which focuses on sociocultural practices, addresses what can be called border languaculture. With attention on the Texas-Mexico border in North America, the authors discuss three key features of hybrid practices on the US ‘side’: (1) code-mixing that has a strong rhetorical component; (2) cross-border continuation but transformation of ‘traditional’ forms and conventions associated historically with Spain and Mexico; and (3) creation of ‘new’ hybrid forms and cultural products that establish social affiliations and distinctions. These languacultural features support the central point of the article: that self-positioning in this borderland is characterized by the multiplicity, contradictions and syncretism now being labeled mestizaje. Although cultural change has often been explained through acculturation, the syncretic nature of these border practices is better explained through transculturation, which emphasizes mutual influences and shifting power relations.     

Magnetographic array for the capture and enumeration of single cells and cell pairs

We present a simple microchip device consisting of an overlaid pattern of micromagnets and microwells capable of capturing magnetically labeled cells into well-defined compartments (with accuracies >95%). Its flexible design permits the programmable deposition of single cells for their direct enumeration and pairs of cells for the detailed analysis of cell-cell interactions. This cell arraying device requires no external power and can be operated solely with permanent magnets. Large scale image analysis of cells captured in this array can yield valuable information (e.g., regarding various immune parameters such as the CD4:CD8 ratio) in a miniaturized and portable platform.The emergent need for point-of-care devices has spurred development of simplified platforms to organize cells across well-defined templates.¹ These devices employ passive microwells, immunospecific adhesive islands, and electric, optical, and acoustic traps to manipulate cells.^2–6 In contrast, magnetic templating can control the spatial organization of cells through its ability to readily program ferromagnetic memory states.⁷ While it has been applied to control the deposition of magnetic beads,^8–13 it has not been used to direct the deposition of heterogeneous cell pairs, which may help provide critical insight into the function of single cells.^14,15 As such, we developed a simple magnetographic device capable of arraying single cells and pairs of cells with high fidelity. We show this magnetic templating tool can use immunospecific magnetic labels for both the isolation of cells from blood and their organization into spatially defined wells.We used standard photolithographic techniques to fabricate the microchips (see supplementary material¹⁶). Briefly, an array of 10 × 30 μm cobalt micromagnets were patterned by a photolithographic liftoff process and overlaid with a pattern of dumbbell-shaped microwells formed in SU-8 photoresist (Fig. 1(a)). The micromagnets were designed to produce a predominantly vertical field in the microwells by aligning the ends of the micromagnet at the center of each well of the dumbbell. These features were deposited across an area of ≈400 mm² (>50 000 well pairs per microchip) (Fig. 1(b)). Depending on the programmed magnetization state with respect to the external field, magnetic beads or cells were attracted to one pole and repelled by the other pole of each micromagnet, leading to a biased deposition (Fig. 1(c)).¹²Open in a separate windowFIG. 1.Magnetographic array for single cell analysis. (a) SEM image of the dumbbell-shaped well pairs for capturing magnetically labelled cells. (b) Photograph of the finished device. (c) An array of well pairs displaying a pitch of 60 × 120 μm before (top) and 10 min after the deposition of magnetic beads (bottom).To demonstrate the capability of the array to capture cells into a format amenable for rapid image processing, we organized CD3+ lymphocytes using only hand-held permanent magnets. We isolated CD3+ lymphocytes from blood via positive selection using anti-CD3 magnetic nanoparticles (EasySep™, STEMCELL Technologies) with purities confirmed by flow cytometry (97.8%; see supplementary material¹⁶). We then stained 1 × 10⁶ CD3+ cells with anti-CD8 Alexa-488 and anti-CD4 Alexa-647 (5 μl of each antibody in 100 μl for 20 min; BD Bioscience) to determine the CD4:CD8 ratio, a prognostic ratio for assessing the immune system.^17,18Variably spaced neodymium magnets (0.5 in. × 0.5 in. × 1 in.; K&J Magnetics, Inc.) were fixed on either side of the microchip to generate a tunable magnetic field (0–400 G; Fig. 2(a)). Using this setup, fluorescently labeled cells were deposited, and the populations of CD4+ and CD8+ cells were indiscriminately arrayed, imaged, and enumerated using ImageJ. The resulting CD4:CD8 ratio of 1.84 ± 0.18 (Fig. 2(b)) was confirmed by flow cytometry with a high correlation (5.4% difference; Fig. 2(c)), indicating the magnetographic microarray can pattern cells for the rapid and accurate assessment of critical phenotypical parameters without complex equipment (e.g., function generators or flow cytometers).Open in a separate windowFIG. 2.CD8 analysis of CD3+ lymphocytes. (a) Photograph of the magnetographic device activated by permanent magnets (covered with green tape). The CD4:CD8 ratio determined by the (b) magnetographic microarray and (c) and (d) flow cytometry was 1.84 and 1.74, respectively.More complex operations, such as the programmed deposition of cell pairs, can be achieved by leveraging the switchable, bistable magnetization of the micromagnets for the detailed studies of cell-cell interactions (Figs. 3(a)–3(d)).¹² For these studies, a 200 G horizontal field generated from an electromagnetic coil was used to magnetize the micromagnets.¹⁹ We then captured different concentrations of magnetic beads as surrogates for cells (8.4 μm polystyrene, Spherotech, Inc.) and found that higher bead concentrations did not affect the capture accuracy (>95%; see supplementary material¹⁶).Open in a separate windowFIG. 3.Programmed pairing of magnetic beads and CD3+ lymphocytes. (a) Schematic of the magnetographic cell pair isolations. (b) Polarized micromagnets isolate cells of one type to one side in a vertical magnetic field and then cells of a second type to the other side when the field is reversed. (c) Fluorescent image of magnetically trapped green stained (top) and red stained (bottom) cell pairs. (d) SEM image of magnetically labeled cells in the microwells. (e) Capture accuracy of magnetic bead pairs. (Each color (and shape) represents the field strength of the reversed field.) (f) Change in the capture accuracy (loss) of initially captured beads after reversing the magnetic field. The capture accuracy of (g) magnetically labeled cell pairs and (h) the second magnetically labeled cell (for (e)–(h): n = 5; time starts from the deposition of the second set of cells or beads).The opposite side of each micromagnet was then populated with the second (yellow fluorescent) bead by reversing the direction of the applied magnetic field. We tested several field strengths (i.e., 10, 25, 40, or 55 G) to optimize the conditions for isolating the desired bead in the opposite well without ejecting the first bead. If the field strength was too large, the previously deposited beads could be ejected from their wells due to the repulsive magnetic force overcoming gravity.¹² As shown in Figure 3(e), increasing the field strength from 10 to 25 G significantly increased the capture accuracy at 60 min from the deposition of the second bead (p < 0.01), but increases from 25 to 55 G did not affect the capture accuracy (p > 0.10). As shown in Figure 3(f), higher field strengths (i.e., 40 and 55 G) resulted in lower capture accuracies compared to lower field strengths (i.e., 10 and 25 G) (p < 0.01), which was primarily due to ejection of the initially captured beads when the micromagnets reversed their polarity.We then arranged pairs of membrane dyed (calcein AM, Invitrogen; PKH26, Sigma) magnetically labeled CD3+ lymphocytes. First, red stained cells (150 μl of 2 × 10⁴ cells/ml) were deposited on the microchip in the presence of 250 G vertical magnetic field. After 20 min, the field was reversed (i.e., to 40, 55, and 70 G) and green stained cells (150 μl of 2 × 10⁴ cells/ml) were deposited on the microchip with images taken in 10 min intervals. Fluorescence images were overlaid (Fig. 3(c)) and the capture accuracy of cell pairs was determined (ImageJ).As seen in Figure 3(g), the capture accuracy of pairs of CD3+ lymphocytes was lower than that of magnetic beads (Fig. 3(e)). However, as shown in Figure 3(h), the second set of cells (green fluorescent) exhibited an average capture accuracy of 91.8% ± 1.9%. This indicates that the lower capture accuracy of cell pairs was either due to the ejection of initially captured (red fluorescent) cells or the migration of initially captured cells through the connecting channel, resulting from their relatively high deformability compared to magnetic beads.In summary, we developed a simple device capable of organizing magnetic particles, cells, and pairs of cells into well-defined compartments. A major advantage of this system is the use of specific magnetic labels to both isolate cells and program their deposition. While the design of this device does not enable dynamic control of the spacing between captured cell pairs as does some dielectrophoresis-based devices,²⁰ it can easily capture cells with high fidelity using only permanent magnets and has clinical relevance in the assessment of immune parameters. These demonstrations potentiate a relatively simple and robust device where highly organized spatial arrangement of cells facilitates rapid and accurate analyses towards a functional and low-cost point-of-care device.     

Disrupting deficit notions of difference: Counter-narratives of teachers and community in urban education

The author reports on research conducted of teachers and their instruction in a US urban public school, with narrative and counter-narrative employed as analytic tools. Central questions guiding the study included: How do teachers’ counter-narratives and experiences influence them in their urban school classrooms? How do teachers’ multiple and varied identities, especially their racial and cultural backgrounds, emerge in their counter-narratives and in their conceptions of and representations of their teaching? And how do teachers’ stories “counter” ways of knowing urban education in the US and influence their interactions with their students and the learning opportunities available in their classrooms? The evidence in the study suggests that although teachers in urban schools may employ pedagogical and curricular tools that differ from many mainstream classrooms, different does not necessarily mean deficit or deficient. The study does not present a romanticized version of the school or those in it; the teachers and students in the study experience adversity and difficulty as is the case with teachers and students in other contexts. However, implications are drawn from the teachers’ successful practices in urban schools to counter, disrupt, and interrupt pervasive discourses that only focus on the negative characteristics of teachers and students in urban schools.