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Bi-directional brain-computer interfaces (BD-BCI) to restore movement and sensation must achieve concurrent operation of recording and decoding of motor commands from the brain and stimulating the brain with somatosensory feedback. Previously we developed and validated a benchtop prototype of a fully implantable BCI system for motor decoding. Here, a prototype artificial sensory stimulator was integrated into the benchtop system to develop a prototype of a fully-implantable BD-BCI. The artificial sensory stimulator incorporates an active charge balancing mechanism based on pulse-width modulation to ensure safe stimulation for chronically interfaced electrodes to prevent damage to brain tissue and electrodes. The feasibility of the BD-BCI system's active charge balancing was tested in phantom brain tissue. With the charge-balancing, the removal of the residual charges on an electrode was evident. This is a critical milestone toward fully-implantable BD-BCI systems.

Despite the promise of Informal Science Learning settings (ISLs) in supporting youth science engagement in ways that value their experiences and communities, in practice, such opportunities are limited. While some ISLs promote more culturally relevant approaches to science engagement, many still reflect White supremacist and patriarchal worldviews in discourse and practice. In Research Practice Partnerships, we engaged eight ISL educators from two partner sites--a community center and science center, and youth from across their six programs. Using participatory ethnography we explore how educators' pedagogical practices supported youth in codeveloping more justice-oriented ISL experiences--experiences which disrupt these dominant and oppressive norms. Our analysis pays attention, in particular, to those fraught moments when youth, in interaction with peers and educators, sought to disrupt their ISL experience in ways that centered and amplified their lives, hopes, and desires for being and learning in ISL and humanized the ISL learning community. Two kinds of pedagogical response patterns emerged that we report on in our findings: (1) "collaborative critique" and (2) "critically being with each other towards new relationalities." We discuss how these two practices centered political and ethical dimensions of teaching and learning, fundamentally shifting power and relationalities towards new ISL possibilities. We also discuss how these practices involved leveraging specific moments to resee youths' activities in new ways, making visible how an ISL space limited opportunities for youth visibility of presence in science--a kind of pausing for justice.

Objective: To assess the feasibility of using a novel device designed for minimally invasive suturing to anchor fetal membranes to the uterine wall and to close surgical defects after fetoscopy. Methods: We tested the WestStitch™ suturing device both ex vivo and in vivo. In the ex‐vivo studies, 12‐Fr trocar defects were created with a fetoscope in five specimens of human uterine tissue with fetal membranes attached. Specimens were examined for integrity of the anchoring stitch. For the in‐vivo studies, trocar defects were created in the two uterine horns of three pregnant ewes, each carrying twins at approximately 79–90 days' gestation. One trocar defect in each ewe was repaired using the suture device, and the other was left unrepaired as a control. The repair sites were examined for membrane‐anchoring integrity when the defect was created and at delivery. Results: Fetal membranes were anchored successfully to the uterine myometrium using the suture‐delivery device in all five experiments performed ex vivo. The in‐vivo experiments also revealed successful membrane anchoring compared with controls, both at the time of device deployment and 1–9 weeks after the procedure. Conclusions: We successfully anchored amniotic membranes to the underlying myometrium using a suturing device, both ex vivo and in vivo. Further studies are needed to evaluate the efficacy of the device and to determine whether it can successfully anchor fetal membranes percutaneously in human patients. © 2024 International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

H2 permeation in peroxide-crosslinked EPDM blended with carbon black (CB) and silica fillers was studied at pressures ranging from 1.2 MPa to 90 MPa via the volumetric analysis technique. H2 uptake in the CB-filled EPDM revealed dual-sorption behaviors via Henry’s law and the Langmuir model, which were attributed to H2 absorption by the polymer chains and H2 adsorption at the filler interfaces, respectively. Additionally, single-sorption mechanisms were observed for neat EPDM and silica-blended EPDM according to Henry’s law, indicating H2 absorption by the polymer chain. The linear decreases in the diffusivity with filler content for the silica-blended EPDMs were attributed to increases in the diffusion paths caused by the filler. Exponential decreases in the diffusivity with increasing filler content and in the permeation with the physical/mechanical properties for CB-filled EPDMs were caused by decreases in the fractional free volume due to increased densities for the EPDM composites. Moreover, good filler-dependent correlations between permeability and density, hardness, and tensile strength were demonstrated for EPDMs used as sealing materials for O-rings. From the resulting equation, we predicted the permeation value without further measurements. Thus, we can select EPDM candidates satisfying the permeation guidelines used in hydrogen infrastructure for the future hydrogen economy.

The Gram-negative human pathogen N. gonorrhoeae (Ngo) quickly attaches to epithelial cells, and large numbers of the bacteria remain on the cell surface for prolonged periods. Ngo invades cells but few viable intracellular bacteria are recovered until later stages of infection, leading to the assumption that Ngo is a weak invader. On the cell surface, Ngo quickly recruits CD46-cyt1 to the epithelial cell cortex directly beneath the bacteria and causes its cleavage by metalloproteinases and Presenilin/γSecretease; how these interactions affect the Ngo lifecycle is unknown. Here, we show Ngo induces an autophagic response in the epithelial cell through CD46-cyt1/GOPC, and this response kills early invaders. Throughout infection, the pathogen slowly downregulates CD46-cyt1 and remodeling of lysosomes, another key autophagy component, and these activities ultimately promote intracellular survival. We present a model on the dynamics of Ngo infection and describe how this dual interference with the autophagic pathway allows late invaders to survive within the cell.