Developmental Differences in Relations Between Episodic Memory and Hippocampal Subregion Volume During Early Childhood

Episodic memory shows striking improvement during early childhood. However, neural contributions to these behavioral changes are not well understood. This study examined associations between episodic memory and volume of subregions (head, body, and tail) of the hippocampus—a structure known to support episodic memory in school‐aged children and adults—during early childhood (n = 45). Results revealed significant positive relations between episodic memory and volume of the hippocampal head in both the left and right hemispheres for 6‐ but not 4‐year‐old children, suggesting brain–behavior relations vary across development. These findings add new information regarding neural mechanisms of change in memory development during early childhood and suggest that developmental differences in hippocampal subregions may contribute to age‐related differences in episodic memory ability.     

Fostering Instructor Knowledge of Student Thinking Using The Flipped Classroom

Abstract

In this article, we share a model of flipped instruction that allowed us to gain a window into our students’ mathematical thinking. We depict how that increased awareness of student thinking shaped our mathematics instruction in productive ways. Drawing on our experiences with students in our own classrooms, we show how flipped instruction can be used to design experiences that help students make sense of mathematics during class sessions.     

Professional development to support principals' vision of science instruction: Building from their prior experiences to support the science practices

The implementation of science reform must be viewed as a systems-level problem and not just focus on resources for teachers and students. High-capacity instructional leadership is essential for supporting classroom science instruction. Recent reform efforts include a shift from learning about science facts to figuring out scientific phenomena in which students use science practices as they build and apply disciplinary core ideas. We report findings from a research study on professional development (PD) to support instructional leaders' learning about the science practices. After participating in the PD, the instructional leaders' familiarity with and leadership content knowledge of the science practices significantly improved. Initially, principals used their understandings from other disciplines and content neutral visions of classrooms to make sense of science instruction. For example, they initially used their understandings of models and argument from ELA and math to make sense of science classroom instruction. Furthermore, some principals focused on content neutral strategies, like a clear objective. Over the course of the PD workshops, principals took up the language of the science practices in more nuanced and sophisticated ways. Principals' use of the language of the science practices became more frequent and shifted from identifying or defining them to considering quality and implementation in science classrooms. As we design tools to support science, we need to consider instructional leaders as important stakeholders and develop resources to specifically meet their needs. If the science feels too unfamiliar or intimidating, principals may avoid or reframe science reform efforts. Consequently, it is important to leverage instructional leaders' resources from other disciplines and content neutral strategies as bridges for building understanding in science. We argue that the science practices are one potential lever to engage in this work and shift instructional leaders' understandings of science instruction.     

Exploring the experiences and responses of LGBTQ+ adolescents to school-based sexuality education

The purpose of this study is to describe the experiences of lesbian, gay, bisexual, transgender, questioning, intersex, two spirit, and queer (LGBTQ+) youth with school-based sexuality education (SBSE), as well as to document strategies LGBTQ+ youth are using to address their evolving and specific sexual health needs outside of SBSE. Researchers conducted focus groups with 17 adolescents (ages 14–18) from urban and suburban Midwestern cities. Results of this study indicate LGBTQ+ youth find SBSE to be heteronormative, cisgender focused, and primarily focused on pregnancy and disease prevention, which contributes to LGBTQ+ youth experiences of exclusion. In response to SBSE that did not meet student needs, participants reported seeking sexual health information outside of SBSE. Other sources included family and other trusted adults, the Internet, and community resource centers. Students reported variable rates of use and trustworthiness across these resources. Results of this study suggest that school personnel should consider alternatives to traditional SBSE models to meet the needs of LGBTQ+ youth, and that an important part of SBSE should include guidelines for Internet safety.     

The professional role and exercise of the role of educational assistance professionals in schools with School Integration Programs in Chile

The incorporation of health professionals into inclusive schools is increasingly necessary. However, the work of these professionals has not yet been studied globally. This qualitative research analyses the perceptions of speech therapists, psychologists, physical therapists and occupational therapists on the role that educational policy defines for working in schools with School Integration Programmes in Chile. Through chain sampling, 52 professionals were interviewed. The data were analysed inductively through thematic analysis. The results show that the role defined by policies for professionals is not in line with the needs of schools and the aspirations of the inclusive approach. The exercise of the role emerges as a distinct entity from the defined role that seems to be more responsive to the needs of schools and students. Interviewees described tensions related to the role in schools, professional training, working conditions and contextual features that would permeate the role that the policy mandates them to play. The findings of the study promote new research horizons related to the role of professional assistants, where research is still incipient worldwide, and invite reflection on the importance of designing education policies with a bottom-up approach to capture the needs presented by learners and professional teams.     

Optical chromatographic sample separation of hydrodynamically focused mixtures

Optical chromatography relies on the balance between the opposing optical and fluid drag forces acting on a particle. A typical configuration involves a loosely focused laser directly counter to the flow of particle-laden fluid passing through a microfluidic device. This equilibrium depends on the intrinsic properties of the particle, including size, shape, and refractive index. As such, uniquely fine separations are possible using this technique. Here, we demonstrate how matching the diameter of a microfluidic flow channel to that of the focusing laser in concert with a unique microfluidic platform can be used as a method to fractionate closely related particles in a mixed sample. This microfluidic network allows for a monodisperse sample of both polystyrene and poly(methyl methacrylate) spheres to be injected, hydrodynamically focused, and completely separated. To test the limit of separation, a mixed polystyrene sample containing two particles varying in diameter by less than 0.5 μm was run in the system. The analysis of the resulting separation sets the framework for continued work to perform ultra-fine separations.     

Solution pH change in non-uniform alternating current electric fields at frequencies above the electrode charging frequency

AC Faradaic reactions have been reported as a mechanism inducing non-ideal phenomena such as flow reversal and cell deformation in electrokinetic microfluidic systems. Prior published work described experiments in parallel electrode arrays below the electrode charging frequency (f_c), the frequency for electrical double layer charging at the electrode. However, 2D spatially non-uniform AC electric fields are required for applications such as in plane AC electroosmosis, AC electrothermal pumps, and dielectrophoresis. Many microscale experimental applications utilize AC frequencies around or above f_c. In this work, a pH sensitive fluorescein sodium salt dye was used to detect [H⁺] as an indicator of Faradaic reactions in aqueous solutions within non-uniform AC electric fields. Comparison experiments with (a) parallel (2D uniform fields) electrodes and (b) organic media were employed to deduce the electrode charging mechanism at 5 kHz (1.5f_c). Time dependency analysis illustrated that Faradaic reactions exist above the theoretically predicted electrode charging frequency. Spatial analysis showed [H⁺] varied spatially due to electric field non-uniformities and local pH changed at length scales greater than 50 μm away from the electrode surface. Thus, non-uniform AC fields yielded spatially varied pH gradients as a direct consequence of ion path length differences while uniform fields did not yield pH gradients; the latter is consistent with prior published data. Frequency dependence was examined from 5 kHz to 12 kHz at 5.5 V_pp potential, and voltage dependency was explored from 3.5 to 7.5 V_pp at 5 kHz. Results suggest that Faradaic reactions can still proceed within electrochemical systems in the absence of well-established electrical double layers. This work also illustrates that in microfluidic systems, spatial medium variations must be considered as a function of experiment time, initial medium conditions, electric signal potential, frequency, and spatial position.     

Strategic ambiguity in the role development process

Today's turbulent business and social environment often compels organizations to adopt internal programs that will help them cope with complexity. One organizational sector in which this is particularly true is the health care industry, as managed care programs and competitive forces have changed the way hospitals and clinics operate. This study looks at a specific organizational program designed to cope with these industry changes and considers the impact of the program on the nurses involved. Drawing on theory and research on role development and strategic ambiguity, this case analysis looks at a hospital system in which the nursing role of “care coordinator”; was defined in a strategically ambiguous way. After analyzing interviews with 19 care coordinators, conclusions are drawn regarding affective reactions to strategic role ambiguity, behavioral adaptation to strategic role ambiguity, and the importance of conceptualizing role ambiguity as a systemic process.