22484 research outputs found
Sort by
Impact of Prior Knowledge on Student Learning: A Narrative Review
No full textIn a learning environment, prior knowledge refers to the knowledge that learners already possess before acquiring new information on a particular topic. Prior knowledge can either support or hinder the learning process. However, inaccurate prior knowledge can be detrimental to learners' ability to acquire new information because it can create misconceptions. This paper aims to review the impact of prior knowledge on student learning, discussing its importance and challenges, and further aims to suggest instructional strategies that educators can employ to help students activate prior knowledge while addressing misconceptions. Accordingly, strategies such as promoting meaningful learning, knowledge retrieval exercises, narrowing the gap between what instructors expect and what students know (knowledge base), and facilitating culturally responsive resources were discussed as key strategies that can be instrumental in the accurate activation of prior knowledge and in addressing misconceptions, ensuring that prior knowledge functions as a foundation for deeper understanding rather than a barrier to new knowledge acquisition
The Pittsburgh Hill/Homewood Research on Neighborhoods and Health (PHRESH)
No full textThe Pittsburgh Hill/Homewood Research on Neighborhoods and Health (PHRESH) is a community-based and engaged suite of research studies in the Hill District and Homewood communities that began in 2011. PHRESH began to understand the impact on resident diet and food purchasing of the new full-service supermarket that opened in the Hill District in 2013. Since 2011, PHRESH has examined whether and how neighborhood investments including greenspace renovations, housing improvements, and commercial development impact resident health. The study has worked with community partners and stakeholders for nearly 15 years. We have had a field office in the Hill District since 2011, where our full-time Field Coordinator (responsible for all data collectors and data collection) sits, and which also serves as a physical resource for the households enrolled in the study. Our current research has focused on how changing neighborhood conditions throughout life contribute to healthy aging, including thinking and memory
Exploring the associations between future orientation and mental health outcomes among youth impacted by community violence
No full textCommunity violence disproportionately affects youth residing in neighborhoods impacted by structural inequities and increases risk for mental health symptoms, including anxiety, depression, and post-traumatic stress. Future orientation—the way young people perceive and plan for their future—can serve as a protective factor, fostering resilience in the context of violence exposure. Through community-partnered, interdisciplinary research, we aim to identify pathways that strengthen youth resilience and inform community-driven interventions. In partnership with youth-serving organizations in Pittsburgh, this study utilizes a cross-sectional social network survey to examine relationships between violence exposure and mental health outcomes among youth ages 13-19. We additionally explore the potential buffering effect of future orientation on mental health outcomes among those who have experienced violence. This work underscores the need for engaged scholarship that bridges research and practice to promote long-term well-being among youth residing in communities affected by violence
Distinct transmission sites within a synapse for strengthening and homeostasis.
No full textAt synapses, miniature synaptic transmission forms the basic unit of evoked transmission, thought to use one canonical transmission site. Two general types of synaptic plasticity, associative plasticity to change synaptic weights and homeostatic plasticity to maintain an excitatory balance, are so far thought to be expressed at individual canonical sites in principal neurons of the cortex. Here, we report two separate types of transmission sites, termed silenceable and idle-able, each participating distinctly in evoked or miniature transmission in the mouse visual cortex. Both sites operated with a postsynaptic binary mode with different unitary sizes and mechanisms. During postnatal development, silenceable sites were unsilenced by associative plasticity with α-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA)-receptor incorporation, increasing evoked transmission. Concurrently, miniature transmission remained constant, where AMPA-receptor state changes balanced unsilencing with increased idling at idle-able sites. Thus, individual cortical spine synapses mediated two parallel, interacting types of transmission, which predominantly contributed to either associative or homeostatic plasticity
Human Metapneumovirus Small Hydrophobic Protein Degrades JAKs to Block Immune Signals
No full textHuman metapneumovirus (HMPV) is an enveloped, single-stranded negative-sense RNA virus in the family Pneumoviridae and is a leading cause of acute lower respiratory tract infections in pediatric and geriatric populations. Since its discovery in 2001, HMPV has been appreciated as a major source of morbidity and mortality. Infection promotes elevation of many inflammatory cytokines, and animal models suggest that these innate immune signals, especially the interferon response, may play an outsized role in causing severe HMPV disease. As a result, understanding how HMPV interacts with and modulates the innate immune response is critically important. Our previous research indicated a role for the HMPV small hydrophobic (SH) protein in inhibiting the JAK/STAT signaling-mediated interferon response in infected cells; however, no mechanism was established. Other research indicated that HMPV infection could deplete JAK signaling proteins in infected cells and separately that HMPV infection could block the IL-6 JAK/STAT signaling pathway, though the viral protein(s) responsible were not identified. Our research established for the first time that SH is responsible for IL-6 signaling inhibition during HMPV infection and that this is accomplished through an SH-dependent depletion of JAK signaling factors required for both interferon and IL-6 signal transduction. This dissertation also provides a summary of JAK/STAT signaling inhibition in the viral families Pneumoviridae and Paramyxoviridae and reviews existing research on SH proteins expressed in the same. This research enhances our understanding of critical mechanisms of immune evasion and interference by diverse pathogens important to public health
Transitional Marketing: Interplay between Online and Offline Business Models
No full textThis dissertation consists of two studies that investigate the transformative impact of digital technology and platform economy on various aspects of Marketing. The first study analyzes the transactional data from a multi-channel retailer in the U.S. that closed many of its brick-and-mortar stores. After the closure, households made fewer trips to the focal retailer, while had a greater basket size for the trips after the closure. These new shopping habits are formed in a short span of two months following the announcement of closure, which highlights a limited time window for retailers to attract these transitional consumers. Households that used to shop in multiple departments before the closure of stores had a greater propensity to stick with the retailer and shift towards the online channel. The second study considers a subscription platform that offers services to variety seeking consumers who incorporate transportation costs in their decision of how many and which vendor services to consume. For the platform to be successful, it should enter markets where consumers’ added benefit from patronizing more than one vendor is relatively high, thus strengthening the position of the platform in negotiations with the vendors. As well, managers should consider entering markets where competition between the vendors is relatively weak, and in particular, where vendors benefit from local monopoly positions due to high transportation costs incurred by consumers. Last, it is important to identify tools that facilitate alleviated price competition with vendors. Negotiating over an appropriate transfer fee per customer to pay the vendor or imposing restrictions on the level of service that their customers can use may be such tools
Microelectronic Devices for Optimizing Neuromorphic Computing Hardware Engineering
No full textNeuromorphic computing, inspired by the structure and function of the human brain, represents a transformative approach to computing. By using artificial neuron and synapse hardware, biological principles can be applied to neural networks to perform tasks in a manner akin to brain function. Various emerging non-volatile memory (NVM) devices, such as resistive random-access memory (RRAM) and phase-change memory (PCM), have been proposed for neuromorphic applications. However, these devices face challenges due to the complex thermal-electrical processes and electrochemical reactions involved, which hinder their performance.
To address these challenges, we first present a study of the transient response of thermoelectric devices to optimize thermal management in spiking neuron networks (SNN) and spike-driven neuromorphic computing hardware. We fabricated a micro-scale silicon thermoelectric cooler (TEC) and conducted measurements to validate our model's predictions. Our results elucidate the transient temperature modulation capabilities of the TEC, its energy efficiency, and the effect of material properties and operation frequency. This work provides a foundation for the theoretical analysis of transient thermal management in emerging spiking-driven devices and neuromorphic hardware.
Additionally, we introduce a novel CMOS-compatible protonic memristor. In contrast to conventional oxygen-based or metal-cation-based memristors, protonic memristors exhibit a significantly smaller ion size, resulting in lower activation energy barriers and faster diffusion speeds. Our experiments demonstrate a notably faster pulse response in protonic memristors compared to their conventional counterparts. Moreover, due to the simple electrochemical processes governing its operation, the protonic memristor performs reliably in diverse environments, such as vacuum and high moisture conditions. This study underscores the potential of proton-based devices in high-speed neuromorphic computing applications, including spiking-rate dependent plasticity (SRDP)
A Configurable CPG Controller using Connectome based SNN on FPGA for Robot Locomotion
No full textMovement control in autonomous robots requires low-power, real-time models, especially for bio-mimetic locomotion in challenging terrains. Human intervention is often impractical in such environments, making specialized neural networks like central pattern geterators critical for offloading computational resources. This paper presents a controller for a bipedal robot using a modified spiking neuron model, adapted for efficient deployment on field-programmable gate arrays. Key modifications were made to ensure lightweight, real-time performance. Additionally, we leverage a unique open-source neuromorphic software platform for the network design and deployment, making the technology accessible to developers aiming to implement autonomous robot locomotion
Regulation of dendritic cell functions by CD91 and its ligand heat shock proteins during immunosurveillance of emerging tumors
No full textDuring cancer immunosurveillance, dendritic cells (DCs) play a central role in orchestrating T cell responses against emerging tumors. Capture of miniscule amounts of antigen along with tumor-derived costimulatory signals can drive maturation and activation of DCs. Expression of the heat shock protein receptor CD91 on DCs is essential in the cross-priming of T cell responses in the context of nascent tumors. There are multiple DC and macrophage subsets that express CD91 and engage tumor-derived gp96 to initiate anti-tumor immune responses, yet the specific CD91+ APCs that are required for efficient T cell cross-priming during cancer immunosurveillance are unknown. We determined that CD91 expression on type 1 conventional DCs is necessary for cancer immunosurveillance, specifically for capture of CD91 ligand, gp96. However, gp96+ cDC1 only facilitate early tumor control, while sustained and long-term tumor rejection is bestowed to the host by other gp96+ cross-priming DCs following intercellular transfer of gp96 between migratory and resident APCs and specific T cell activation. We show the CD91-induced transcriptome in APCs promotes cross-priming of T cell responses while downregulating immune regulatory pathways. Our results show an elaborate and synchronized division of labor amongst APCs for the successful elimination of cancer cells. The specialized functions of APC subsets can be coordinately harnessed for effective immunotherapy of cancer
Conversations for Change: A Discourse & Dialogue Series
No full textThe Office for Equity, Diversity, and Inclusion in partnership with the Division of Student Affairs, presents Conversations for Change--an engaging and thought-provoking series designed to foster meaningful dialogue on critical social issues. This series offers a safe space for participants to explore diverse perspectives, share experiences, and collaborate on solutions that promote equity, inclusion, and positive change. Each session will focus on a key topic and feature guest speakers, interactive discussions, and opportunities for open dialogue. Whether you're passionate about social justice, community building, or simply want to listen and learn, we welcome your participation