Maturation of NaV and KV channel topographies in the auditory nerve spike initiator before and after developmental onset of hearing function

Auditory nerve excitation and thus hearing depend on spike-generating ion channels and their placement along the axons of auditory nerve fibers (ANFs). The developmental expression patterns and native axonal locations of voltage-gated ion channels in ANFs are unknown. Therefore, we examined the development of heminodes and nodes of Ranvier in the peripheral axons of type I ANFs in the rat cochlea with immunohistochemistry and confocal microscopy. Nodal structures presumably supporting presensory spiking formed between postnatal days 5 (P5) and P7, including Ankyrin-G, NaV1.6, and Caspr. These immature nodal structures lacked low-voltage-activated KV1.1 which was not enriched at juxtaparanodes until approximately P13, concurrent with the developmental onset of acoustic hearing function. Anatomical alignment of ANF spike-initiating heminodes relative to excitatory input from inner hair cell (IHC) ribbon synapses continued until approximately P30. High-voltage-activated KV3.1b and KV2.2 were expressed in mutually exclusive domains: KV3.1b was strictly localized to nodes and heminodes, whereas KV2.2 expression began at the juxtaparanodes and continued centrally along the first internode. At spike-initiating heminodes in the distal osseous spiral lamina, NaV1.1 partly overlapped NaV1.6 and ankyrin-G. ANFs displayed KV7.2 and KV7.3 at heminodes, nodes, internodes, and the unmyelinated synaptic terminal segments beneath IHCs in the organ of Corti. In response to sound, spikes are initiated at the heminode, which is tightly coupled to the IHC ribbon synapse ∼20–40 μm away. These results show that maturation of nodal alignment and ion channel content may underlie postnatal improvements of ANF excitability and discharge synchrony.SIGNIFICANCE STATEMENTAcoustic and electrical hearing depends on rapid, reliable, and precise spike generation in auditory nerve fibers. A limitation of current models and therapies is a lack of information on the identities and topographies of underlying ion channels. We report the developmental profile of the auditory nerve spike generator with a focus on NaV1.1, NaV1.6, KV1.1, KV2.2, KV3.1b, KV7.2, and KV7.3 in relation to the scaffold ankyrin-G. Molecular anatomy of the spike generator matures in the weeks after developmental onset of hearing function. Subcellular positioning of voltage-gated ion channels will enable multicompartmental modeling of auditory nerve responses elicited by afferent chemical neurotransmission from hair cells and modulated by efferent neurotransmitters or evoked by extracellular field stimulation from a cochlear implant.</jats:p

Understanding Point and Slope in Linear Equations and Approximations: A Case Study

This article delves into an intervention designed to enhance a precalculus student’s understanding in constructing linear equations and in approximating function values. Before the intervention, the student primarily relied on the algebraic formula y2-y1/x2-x1 to determine slope, knew slope geometrically as Δy/Δx solely for integer values, and struggled to construct a linear equation without an explicitly shown y-intercept. Through the intervention, the student comprehended slope m as a unit rate and expanded this understanding to Δy = Δ for integer Δx by iterating m, Δ number of times. She also successfully used this newfound understanding to construct linear equations, including tangent line equations, and approximate function values. Nonetheless, she faced some challenges in comprehending Δy = Δ for non-integer Δ and in conceiving point as a multiplicative object with its coordinates representing covarying quantities. Further exploration is needed to validate these findings and address potential difficulties that students might face in grasping slope in the context of linear equations and approximations

Graphs of Two Variable Inequalities: Alternate Approaches to the Solution Test

In this article I suggest some alternatives to the solution test for the understanding of graphs of inequalities in two variables. Based on the work done with two groups of preservice secondary mathematics teachers, and by using the idea of variation and the framework of action and process conceptions of inequalities, I explain how graphs of inequalities can be viewed as a collection of rays or curves. I also explain the potential benefits of these alternative explanations in the solving of optimization problems and in the instruction of functions as a medium of one variable and two variable functions

A teacher's use of play to promote literacy learning in a prekindergarten classroom serving children from diverse language backgrounds

textThis study looked at both a teacher’s beliefs about the role of play and that teacher’s use of play in literacy learning serving children from diverse language backgrounds. Although several researchers have explored children’s literacy development in a play context, there is little research on this topic for children from diverse language backgrounds. In order to explore the role of play in literacy learning for children from diverse language backgrounds, I used a qualitative research approach to collect data from interviews, informal conversations, observations, and self-reflexive notes. In this study, the teacher believed play could be an ideal medium for ESL children who did not speak English fluently. Play gave them a relaxed and comfortable environment to practice a new language, English, without worrying about making mistakes. She understood play as a “concrete,” “hands-on,” “fun,” and “manipulative” activity that provides a relaxed and comfortable environment, becomes a good medium for integrated lessons, and gives a natural connection between the home language and English. She used play for a warm-up, games or tricks, integrated lessons, assessment, acting out characters, dramatic play, and block play in literacy learning for children from diverse language backgrounds. This study revealed that when a teacher believes that play takes an important role in children’s learning and development, she uses playful activities as potential teaching and learning mediums for ESL children’s literacy learning and development. In addition, the result supported that each teacher may have a unique understanding or practical notion of play in literacy learning, and it may strongly affect his/her classroom practices.Curriculum and Instructio

Cultural Hybridity in the Contemporary Korean Popular Culture through the Practice of Genre Transformation

The focus of this dissertation is to show how the media of contemporary Korean popular culture, specifically films, are transformed into “hybrid cultural forms” through the practice of genre transformation. Since the early 21st century, South Korean popular culture has been increasingly spreading across the globe. Despite its growing attention and popularity, Korean pop culture has been criticized for its explicit copying of Western culture with no unique cultural identity. Others view the success of Korean media, both its creative mimicry and its critique of the West, as a new hybrid form that offers the opportunity for reassertion of local identity as well as challenging the global hegemony of the West. Chapter 1 explains the focus of my study and objectives, research questions, methods and background. Chapter 2 provides a literature review that examines the major scholarly works that characterize contemporary Korean film and surveys the historical development of Korean popular culture in its historical and social context. Chapter 3 considers how I approach Korean films from the perspective of theories of cultural hybridity and film genre, introducing the work of Homi Bhabha, Rick Altman, Thomas Schatz, John Cawelti and other scholars. The two chapters that follow analyze the case studies of two genre films—the Korean Western, The Good, the Bad, the Weird (2008) and the post-apocalyptic sci-fi action film, Snowpiercer (2013)—to elucidate how these films function as a “hybrid cultural form,” and how the practice of genre transformation has a role in unsettling and changing the cultural messages and codes of the dominant culture’s forms. This dissertation argues that cultural hybridization is a key survival strategy of the contemporary Korean media production commercially, aesthetically and culturally. The practice of genre transformation plays a decisive role in creating cultural hybrid texts, which contribute not only to increasing cultural exchange and dissemination but also to the artistic development of cultural expression and, more importantly, to enhancing cultural diversity in an age of global transnationalism

Antagonistic Regulation of Circadian Output and Synaptic Development by JETLAG and the DYSCHRONIC-SLOWPOKE Complex

Circadian output genes act downstream of the clock to promote rhythmic changes in behavior and physiology, yet their molecular and cellular functions are not well understood. Here we characterize an interaction between regulators of circadian entrainment, output, and synaptic development in Drosophila that influences clock-driven anticipatory increases in morning and evening activity. We previously showed the JETLAG (JET) E3 ubiquitin ligase resets the clock upon light exposure, whereas the PDZ protein DYSCHRONIC (DYSC) regulates circadian locomotor output and synaptic development. Surprisingly, we find that JET and DYSC antagonistically regulate synaptic development at the larval neuromuscular junction, and reduced JET activity rescues arrhythmicity of dysc mutants. Consistent with our prior finding that DYSC regulates SLOWPOKE (SLO) potassium channel expression, jet mutations also rescue circadian and synaptic phenotypes in slo mutants. Collectively, our data suggest that JET, DYSC, and SLO promote circadian output in part by regulating synaptic morphology

TOGO truck information service: Based on mobile tracking system

In our current economic state, instant gratification from the satisfaction by the real time products and services and experiences are in demand for consumers. As a result, there are several if not many of these real-time base services that have arisen from what the consumers\u27 desire. During the research, I have witnessed the phenomenon that would fit the criteria. The perfect example would be the popularity of meals on wheels in the United States. Setting a new trend in the fast food market, the food truck industry has reached the numbers well over the thousands and still counting with their own unique ideas and innovations. I can confidently say, with the rise of the food truck industry, we have observed the decline of stationary restaurants. But, unlike the mobile counterpart, the stationary restaurants still have one distinct advantage; consumers know where to find them. For example, when struck with a craving for tacos, it is easier to Google a Mexican restaurant down the street, rather than to track down a taco truck. To counterstrike the stationary opposition to quench the hunger for the food truck enthusiasts, several apps have been created. The applications general idea is to pin point gourmet food trucks on mobile maps to even the reliability of playing fields via Twitter feeds, GPS and truck-reported location data. While none of which has achieved an exhaustive or completely accurate system, the search still continues for trucks for users depending on their location. During the present market condition, I am certain of making an accurate and effective real-time information service would be an interesting subject to approach in satisfying users and business owners desires. In demand of real-time information services, I will create a prototype for a food truck information service, inclusive of real-time location service; GPS, mobile tracking, truck-reported data and alert service. The consumers and the food truck owners will both come out as winners, with relaying precise information via real time communication devices. As a student studying the art of user experience and interaction design, goal of this study is to figure out how to enhance the user friendly interface along with meeting the expectations of actual consumers. In order to have a deeper understanding about interaction between users and real time location applications to heighten the level of services, I am willing to go above and beyond with through research to develop a next generation real time app during this project. Another critical factor that I, a user experience designer would point out would be communication. A key factor in completing the task, finding a significant way of communication method would be an additional goal throughout this project