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In-Vivo Neural Tissue Impedance Measurements with a 126 Channel Silicon Microelectrode
(Johns Hopkins University, 2023-08-16) Bruns, Nicholas Gordon; Harris, Timothy; Gracias, David
Application of electrical stimulation is an indispensable method within neuroscientific research for investigating neural circuits and connectivity. Optogenetic methods of activation and inhibition have dominated rodent animal model applications, thanks to a high degree of specificity and selectivity, but this success is not easy to implement in NHP (non-human primate) models. Further, electrical stimulation is a clinically accepted means of addressing a variety of human neurological conditions through modulating pathological neural activity with applied currents. Therefore, advancements made in delivering precise electrical stimulation in a research context are sooner to see translation towards human applications than optogenetics methods. Currently, Neuropixels probes are demonstrated to be a highly effective intracortical recording platform with both high spatial resolution and channel counts. This entails a single device that can record several different neurons across multiple brain regions simultaneously. However, this high spatial resolution and programmable position selectivity has yet to be extended towards activating neurons, not just recording them. While much work pertaining to electrical neural stimulation predates Neuropixels, as do multichannel stimulating implementations such as the Utah array, these prior technologies operate on a scale orders of magnitude larger than the microscale distances that CMOS based devices like Neuropixels can resolve. Further still, all existing electrical stimulation systems operate with a large margin of uncertainty on the magnitude to which a delivered stimulus is attenuated throughout the chronic interactions between a foreign electrode and a local biological environment. Here, investigation is undertaken to make use of prototype patterned microelectrode shanks with 126 uniquely addressable and permutable TiN electrode sites; with the objective to establish design requirements for a current steering device. Additionally, investigation is also performed to understand the differing magnitudes of impedance changes in-vivo, comparing outcomes between currents sunk to a traditional headscrew, or to various locations on the probe itself. Leveraging the customizable and dynamically specifiable nature of microelectrodes on this device, hereto referred to as a STIMAL probe, insights are expected to be gained on the failure modes of chronically implanted neural interfaces, and their local impedance contributions
‘Decreasing the Distance’ in the Climate Finance Gap: A Multicriteria Analysis of Policy Options to Generate Carbon Revenues from the International Aviation Sector
(Johns Hopkins University, 2024-03-29) Patel, Urvaksh Daraius; Urpelainen, Johannes; Villiger, Erwin; Repnik, Markus
A significant climate finance gap exists in the shortfall between the climate finance mobilized every year and the climate finance needed, which is estimated to increase to the trillions of dollars over the next few decades. Mobilizing these trillions will require scaling-up existing sources of finance while also raising new, innovative, and additional sources. The international aviation sector offers an interesting opportunity to consider a novel way in which a hard-to-abate industry can generate billions of dollars in carbon revenues every year, without any market distorting effects, to be channeled as a source of climate finance. This creates the possibility of a new climate regime for the international aviation sector that would require the adoption of a policy at the global level. Three potential policy options include: a passenger tax, a jet fuel tax, and an aircraft movement tax, but which of these policies is viable for adoption is the central question of this study. To be viable, such a policy should (i) gain the support of major powers, (ii) be politically feasible, (iii) be able to generate adequate (i.e., substantial) revenues, (iv) be easily implementable, and (v) not create market distortions. A multicriteria analysis was undertaken to assess the policy options and found that a passenger tax would be the most viable for adoption among the three options. A jet fuel tax and aircraft movement tax remain possible alternatives but would pose more challenges to international adoption.
Acceleration: Lessons from the Field
(The Johns Hopkins Institute for Education Policy, 2024-03-28) Steiner, David
The Johns Hopkins Institute for Education Policy, supported by the Louis Calder Foundation and Chiefs for Change, has conducted the first in-depth case study of the use of acceleration strategies by public school districts. Through an analysis of documentation and assessment results, interviews with district leadership and school principals, and using multiple classroom observations, the Institute examined district policy and granular practices in math and ELA instruction at the middle school grade levels. Counter to expectations, we found that teachers in whole-class settings were closely following their respective high-quality curricula in both subjects – a key goal of acceleration. We found too that students were being regularly re-grouped for differential small-group and individualized online instruction – a key component of acceleration models. However, we found that the rigor of whole-class instruction was highly variable, even within the same school. We also found widespread skepticism on the part of principals as to the value of digital platform online learning. Finally, based on the assessment data and the observations we made, we can suggest the hypothesis that acceleration works best for students who are modestly behind in their learning (roughly up to a year), but that for those who are several (or more) grade levels behind, more drastic interventions will be necessary.
Social Studies Knowledge Map: The 1619 Project
(Johns Hopkins Institute for Education Policy, 2021-07-28)
The Institute analyzed The 1619 Project as a single-unit set of materials. In addition to the Institute’s team, five additional teacher experts with extensive curriculum expertise evaluated each resource individually and assessed their cumulative impact as a whole.
(Wolf Legal Publishers, 2021) Chrappan, Magdolna; Cseko_Lengyel, Nora; Engler, agnes; balazs, Szabolcs Gerencser; Polonyi, Istvan
(2023-12) Anna Iwasaki
Traveling exhibitions are unique as they bring thoughtfully curated narratives to far-away visitors. Through the displays, visitors can physically immerse themselves in exhibitions to experience and absorb various cultures and histories without being in an academic setting. While there is benefit such as the spread of cultures, there is also the need to recognize how traveling exhibitions are communicated to the visitors and community of the location of the destination. This research will begin by exploring the significance of exhibitions from a wide perspective by examining materials such as exhibition catalogs and journal articles, using a historical studies approach to answer two research questions: how exhibitions in general served the community over time, and what or if any are the theories and models used for exhibition design. Then the research will be narrowed down to examine a specific traveling exhibition with minimum language barrier and analyze using the document analysis approach to answer two research questions: what differences are there in the way an exhibition is communicated in each location, and whether the location and the community in each location affect how the exhibition is communicated. The traveling exhibition, “Flesh and Blood: Masterpieces from the Capodimonte Museum,” is selected as it comprised of artworks from the Capodimonte Museum in Italy and made its way to the Seattle Art Museum and to the Kimbell Art Museum in the United States. This study concludes that there is a strong relationship between the community and the exhibition that is presented in the community, as it offers a unique experience for visitors, such as a space to satisfy curiosities, to learn, and to socialize. Additionally, examining the traveling exhibition “Flesh and Blood” reveals the differences in how the traveling exhibition is presented in each location and recommends that when organizing a traveling exhibition, there are benefits in researching the location that the exhibition will tour such as the local traditions. The findings from this study contribute to the academic research field of traveling exhibitions and may also help guide future studies when examining the relationship between traveling exhibitions and their local visitors
Chapter 12: Music Copyright and Libraries
(Rowan & Littlefield Publichers, Inc., 2023) DeLaurenti, Kathleen; Harbeson, Eric; Pantaloni, Naz
Libraries play a broad range of functional roles in managing music collections, including acquiring and providing access to music and recordings for entertainment, education, or performance purposes; administering and preserving performances; and maintaining archival records of our musical heritage. Fulfilling these roles requires librarians to understand music copyright and the complicated system of music licensing that has developed in the United States.
Impact Evaluation of Imagine MyPath in Moline-Coal Valley School District
(Center for Research and Reform in Education, 2023-11) Cook, Michael; Storey, Nathan; Eisinger, Jane; Barros, Maria Jose; Ross, Steven
The current study was a mixed-methods evaluation designed to provide efficacy evidence for Imagine Learning’s Imagine MyPath program, as well as data regarding program implementation and teacher perceptions. Achievement impacts were determined by comparing treatment students in kindergarten in the Moline-Coal Valley School District to comparison students identified by NWEA’s Similar Schools Report who did not use the program. Results of the main impact analyses showed mixed patterns of results regarding the efficacy of Imagine MyPath. A significant positive impact of Imagine MyPath on student mathematics achievement gains was evidenced, with treatment students outgaining virtual comparison students by slightly more than 2 points on the NWEA MAP Growth Mathematics assessment. Perceptions of the Imagine MyPath program from Moline-Coal Valley School District teachers were generally positive. Overall, the majority of teachers agreed they would like to use the program again in the future and would recommend it to others. Teachers were highly positive regarding the organization of the program and its impact on student learning. Most teachers agreed that Imagine MyPath helped students improve their reading and mathematics skills and that the program addressed gaps in their knowledge about these subjects. They also largely agreed that the program placed students at the appropriate level initially, challenged them appropriately throughout the program, presented them with content appropriate to their skill level, motivated them to persist through difficult content, and met the needs of diverse learners.
(2023-12) Thomas Patrick Blair
Mechanical and chemical plant structures are important factors in determining herbivorous insect assemblages. During the summer of 2017, 2015 caterpillars (Lepidoptera), classified as either shelter builders or exposed feeders, were collected by hand from 40 felled trees in an oak-hickory temperate forest located in Toms Brook (Shenandoah County, Virginia, eastern USA). Preserved caterpillars were identified by morphological and molecular characteristics. I explored whether there are statistical relationships between caterpillar abundance and plant mechanical traits, such as leaf thickness, leaf toughness, and relative tree height. As a group, caterpillars were concentrated in the relative middle height of each trees’ canopy. Leaf thickness - but not leaf toughness - was correlated to overall caterpillar abundance. Specifically, shelter builders were more abundant on thicker leaves, and, in contrast, exposed feeding caterpillars were more abundant on thinner leaves. Whether caterpillars are shelter builders or exposed feeders, it appears that their presence within a tree varies substantially, and that this variation is related, in part, to relative canopy location and to leaf thickness. Also, these results support the hypothesis that leaves in the relative upper canopy, as defined by a relative tree height formula, experience reduced herbivory possibly due to abiotic factors, such as decreased water availability and increased exposure to UV radiation both of which reduce their nutritional content and palatability.