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Evoking stable and precise tactile sensations via multi-electrode intracortical microstimulation of the somatosensory cortex
Get PDFTactile feedback from brain-controlled bionic hands can be partially restored via intracortical microstimulation (ICMS) of the primary somatosensory cortex. In ICMS, the location of percepts depends on the electrode’s location and the percept intensity depends on the stimulation frequency and amplitude. Sensors on a bionic hand can thus be linked to somatotopically appropriate electrodes, and the contact force of each sensor can be used to determine the amplitude of a stimulus. Here we report a systematic investigation of the localization and intensity of ICMS-evoked percepts in three participants with cervical spinal cord injury. A retrospective analysis of projected fields showed that they were typically composed of a focal hotspot with diffuse borders, arrayed somatotopically in keeping with their underlying receptive fields and stable throughout the duration of the study. When testing the participants’ ability to rapidly localize a single ICMS presentation, individual electrodes typically evoked only weak sensations, making object localization and discrimination difficult. However, overlapping projected fields from multiple electrodes produced more localizable and intense sensations and allowed for a more precise use of a bionic hand
Universal coherent atom-molecule oscillations in the dynamics of the unitary Bose gas near a narrow Feshbach resonance
Get PDFQuench experiments on a unitary Bose gas around a broad Feshbach resonance have led to the discovery of universal dynamics. This universality manifests in the measured atomic momentum distributions, where, asymptotically, a quasiequilibrated metastable state is found in which both the momentum distribution and the timescales are determined by the particle density. In this Letter we present counterpart studies for the case of a very narrow Feshbach resonance of atoms with a width of 8.3 mG. In dramatic contrast to the behavior reported earlier, a rapid quench of an atomic condensate to unitarity is observed to ultimately lead to coherent oscillations involving dynamically produced condensed and noncondensed molecules and atoms. The same characteristic frequency, determined by the Feshbach coupling, is observed in all types of particles. To understand these quench dynamics and how these different particle species are created, we develop a beyond Hartree-Fock-Bogoliubov dynamical framework including a type of cross-correlation between atoms and molecules. This leads to quantitative consistency with the measured frequency. Our results, which can be applied to the general class of bosonic superfluids associated with narrow Feshbach resonances, establish a alternate paradigm for universal dynamics dominated by quantum many-body interactions
A paradoxical population structure of <i>var</i> DBLα types in Africa
Get PDFThe var multigene family encodes Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1), central to host-parasite interactions. Genome structure studies have identified three major groups of var genes by specific upstream sequences (upsA, B, or C). Var with these ups groups have different chromosomal locations, transcriptional directions, and associations with disease severity. Here we explore temporal and spatial diversity of a region of var genes encoding the DBLα domain of PfEMP1 in Africa. By applying a novel ups classification algorithm (cUps) to publicly-available DBLα sequence datasets, we categorised DBLα according to association with the three ups groups, thereby avoiding the need to sequence complete genes. Data from deep sequencing of DBLα types in a local population in northern Ghana surveyed seven times from 2012 to 2017 found variants with rare-to-moderate-to-extreme frequencies, and the common variants were temporally stable in this local endemic area. Furthermore, we observed that every isolate repertoire, whether mono- or multiclonal, comprised DBLα types occurring with these frequency ranges implying a common genome structure. When comparing African countries of Ghana, Gabon, Malawi, and Uganda, we report that some DBLα types were consistently found at high frequencies in multiple African countries while others were common only at the country level. The implication of these local and pan-Africa population patterns is discussed in terms of advantage to the parasite with regards to within-host adaptation and resilience to malaria control
Favelas e as pós-vidas da cidade escrava / Favelas and the Visual Afterlives of Slavery’s Cities / Favela y la vida después de la muerte de la ciudad esclavista
Get PDFEste artigo examina as representações visuais da urbanidade negra do século XIX ao início do século XX. Considera-se como a urbanidade negra foi vivida, imaginada e visualizada nas cidades do século XIX, enfocando a tensa interdependência entre a cidade escrava (a cidade estruturada pela prática da escravidão) e a cidade negra (a cidade criada por e para os negros). Em seguida, analisa como os fotógrafos municipais representaram as favelas e os mocambos do século XX por meio dos regimes visuais da cidade escrava. Conclui-se que, a despeito de tais representações, o urbanismo informal constituiu sua própria prática visual, permitindo que os afrodescendentes inscrevessem a cidade negra de forma definitiva na tela urbana. This article uses examines how Black urbanity was represented from the 19th to the early 20th centuries. It considers how Black urbanity was lived, imagined, and visualized in the nineteenth-century city, focusing on the tense interdependence between the slave city (the city structured by slavery) and the cidade negra (the city created by and for Black people). It then analyzes how municipal photographers represented 20th century favelas and mocambos through the visual regimes of the slave city. But informal urbanism constituted its own visual practice, allowing Afro-descendants to indelibly inscribe the Black city onto the urban canvas. Este artículo examina las representaciones visuales de la urbanidad negra del siglo XIX y de inicios del XX. Se aborda cómo la urbanidad negra fue vivida, imaginada y visualizada en las ciudades del siglo XIX, enfocándose en la tensa interdependencia entre la ciudad esclava (la ciudad estructurada por la práctica de la esclavitud) y la ciudad negra (la ciudad creada por y para los negros). Seguidamente, se analiza cómo los fotógrafos municipales representaron las favelas y los mocambos del siglo XX a través de los regímenes visuales de la ciudad esclava. Se concluye que, pese a tales representaciones, el urbanismo informal constituyó su propia práctica visual, permitiendo a los afrodescendientes inscribir definitivamente la ciudad negra en el lienzo urbano.</p
NCES NAEP-National Indian Education Survey
No full textNCES NAEP-NIES includes years from 2016-2005 in csv format, Fourth through Eighth grade reading and mathematics assessments and survey data. Survey responses are also included
NCES Education of Longitudinal Study 2002
No full textExcel sheets containing comparative data regarding AP/IB Prevalance and Availability, Career Academies Available in HS, CTE in High School, Employment and Hours Worked, Financial and Employment Status of 2002 HS Sophomores by 2012, GEDs and HS complemetions of 2003-04 graduates by 2006, Marital Status Parental Status Community Service and Military Service, On-time and Late HS Competion of 1992 and 2004 Seniors, Postsecondary Enrollment of of 2003-04 HS Seniors by College Preparation Activities, HS Graduates from 2003-04 Postsecondary Enrollments by 2006, Postsecondary Persistence of 2003-04 HS Graduates by 2006, Postsecondary Student Financial Aid Applications of 2003-04 HS Graduates, Reasons for Postsecondary Enrollment Decisions of 2006, Selected Characteristics of Postsecondary STEM and non-STEM Majors (2006
NCES Academic Library Data Files (ALS)
No full textThe Academic Libraries Survey (ALS) is a periodic survey conducted by the National Center for Education Statistics (NCES) to collect data on academic libraries in the United States. The dataset, available in zip file from the original ASCII format and pdf files, includes survey results from 1996, 1998, 2000, 2002, 2004, 2006, 2008, 2010, 2011, and 2012. It provides comprehensive information on library collections, expenditures, staffing, services, and usage across higher education institutions. These data files are essential for analyzing trends in academic library operations, resource allocation, and service provision over time
Hypothesizing mechanistic links between microbes and disease using knowledge graphs
Get PDFKnowledge graphs have been a useful tool for many biomedical applications because of their effective representation of biological concepts. Plentiful evidence exists linking the gut microbiome to disease in a correlative context, but uncovering the mechanistic explanation for those associations remains a challenge. Here we demonstrate the potential of knowledge graphs to hypothesize plausible mechanistic accounts of host-microbe interactions in disease. We have constructed a knowledge graph of linked microbes, genes and metabolites called MGMLink, and, using a shortest path or template-based search through the graph and a novel path-prioritization methodology based on the structure of the knowledge graph, we show that this knowledge supports inference of mechanistic hypotheses that explain observed relationships between microbes and disease phenotypes. We discuss specific applications of this methodology in inflammatory bowel disease and Parkinson’s disease. This approach enables mechanistic hypotheses surrounding the complex interactions between gut microbes and disease to be generated in a scalable and comprehensive manner