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Abstract Cerebral venous sinus thrombosis (CVST) is a type of stroke associated with COVID‐19 vaccine‐induced immune thrombotic thrombocytopenia. The precise etiology of CVST often remains elusive due to the highly heterogeneous nature of its governing mechanisms, specifically, Virchow's triad that involves altered blood flow, endothelial dysfunction, and hypercoagulability, which varies substantially amongst individuals. Existing diagnostic and monitoring approaches lack the capability to reflect the combination of these patient‐specific thrombotic determinants. In response to this challenge, we introduce a Vein‐Chip platform that recapitulates the CVST vascular anatomy from magnetic resonance venography and the associated hemodynamic flow profile using the “Chinese Movable Type‐like” soft stereolithography technique. The resultant full‐lumen personalized Vein‐Chips, functionalized with endothelial cells, enable in‐vitro thrombosis assays that can elucidate distinct thrombogenic scenarios between normal vascular conditions and those of endothelial dysfunction. The former displayed minimal platelet aggregation and negligible fibrin deposition, while the latter presented significant fibrin extrusion from platelet aggregations. The low‐cost movable typing technique further enhances the potential for commercialization and broader utilization of personalized Vein‐Chips in surgical labs and at‐home monitoring. Future research and development in this direction will pave the way for improved management and prevention of CVST, ultimately benefiting both patients and healthcare systems.

A cybersecurity approach for a large-scale user facility is presented—utilizing the National High Magnetic Field Laboratory (NHMFL) at Florida State University (FSU) as an example. The NHMFL provides access to the highest magnetic fields for scientific research teams from a range of disciplines. The unique challenges of cybersecurity at a widely accessible user facility are showcased, and relevant cybersecurity frameworks for the complex needs of a user facility with industrial-style equipment and hazards are discussed, along with the approach for risk identification and management, which determine cybersecurity requirements and priorities. Essential differences between information technology and research technology are identified, along with unique requirements and constraints. The need to plan for the introduction of new technology and manage legacy technologies with long usage lifecycles is identified in the context of implementing cybersecurity controls rooted in pragmatic decisions to avoid hindering research activities while enabling secure practices, which includes FAIR (findable, accessible, interoperable, and reusable) and open data management principles. The NHMFL’s approach to FAIR data management is presented. Critical success factors include obtaining resources to implement and maintain necessary security protocols, interdisciplinary and diverse skill sets, phased implementation, and shared allocation of NHMFL and FSU responsibilities.

Introduction The risk of hemorrhagic transformation (HT) in the early phase of acute ischemic stroke (AIS) remains unknown, leading to potential unnecessary delays in initiation of anticoagulation for secondary stroke prevention. We sought to assess the rate of HT associated withdirect oral anticoagulant (DOAC) initiation within and beyond 48 hours after AIS, using a pooled analysis of available published data. Methods A pooled analysis of 6 studies (4 prospective observational blinded outcome studies and2 randomized trials) of DOAC initiation within 14 days of AIS or transient ischemic attack (TIA) was conducted. The primary endpoint was incident radiographic HT on follow‐up imaging. Secondary endpoints included symptomatic HT, new parenchymal hemorrhage, recurrent ischemic events, extracranial hemorrhage, mortality within the study period, and follow‐up modified Rankin Scale score.The results were reported as odds ratio (OR) andhazard ratio (HR)with 95% confidence interval (CI). Results We evaluated 509 patients; median infarct volume was1.5 (0.1‐7.8) ml, andmedian National Institutes of Health Stroke Scale was2 (0‐3).Incident radiographic HT was seen on follow‐up scan in 34 (6.8%) patients.DOAC initiation within 48 hours from index event was not associated with incident HT (adjusted OR 0.67, [0.30 – 1.50]P = 0.32).No patients developed symptomatic HT.Conversely, 31 (6.1%) patients developedrecurrent ischemic events, 64% of which occurred within 14 days.Initiating a DOAC within 48 hours of onset was associated with a trend towards lower rates of recurrent ischemic events, but this was not statistically significant (HR 0.42, [0.17 – 1.008]P = 0.052). In contrast to HT,recurrent ischemic events were associated with poor functional outcomes (OR = 6.8, [2.84 – 16.24], p< 0.001). Conclusions Initiation of DOAC within 48 hours after stroke was not associated with decreased risk of recurrent ischemic events, or increasedincident risk of HT. Both recurrent ischemic events and incident HT occurred at similar rates.Unlike HT, however, recurrent ischemic events were associated with poor outcomes.

Cayambe Volcano is an ice-capped, 5,790 m high, andesitic-dacitic volcanic complex, located on the equator in the Eastern Cordillera of the Ecuadorian Andes. An eruption at Cayambe would pose considerable hazards to surrounding communities and a nationally significant agricultural industry. Although the only historically documented eruption was in 1785, it remains persistently restless and long-period (LP) seismicity has been consistently observed at the volcano for over 10 years. However, the sparse monitoring network, and complex interactions between the magmatic, hydrothermal, glacial, and tectonic systems, make unrest at Cayambe challenging to interpret. In June 2016 a seismic “crisis” began at Cayambe, as rates of high frequency volcano-tectonic (VT) earthquakes increased to hundreds of events per day, leading to speculation about the possibility of a forthcoming eruption. The crisis began 2 months after the Mw7.8 Pedernales earthquake, which occurred on the coast, 200 km from Cayambe. Here we show that the 2016 seismicity at Cayambe resulted from four distinct source processes. Cross correlation, template matching, and spectral analysis isolate two source regions for VT earthquakes–tectonic events from a regional fault system and more varied VTs from beneath the volcanic cone. The temporal evolution of the LP seismicity, and mean Q value of 9.9, indicate that these events are most likely generated by flow of hydrothermal fluids. These observations are consistent with a model where a new pulse of magma ascent initially stresses regional tectonic faults, and subsequently drives elevated VT seismicity in the edifice. We draw comparisons from models of volcano-tectonic interactions, and speculate that static stress changes from the Pedernales earthquake put Cayambe volcano in an area of dilation, providing a mechanism for magma ascent. Our findings provide a better understanding of “background” seismicity at Cayambe allowing faster characterization of future crises, and a benchmark to measure changes driven by rapid glacial retreat.

Abstract With increased intensity rainfall events globally and urban expansion decreasing permeable surfaces, there is an increasing problem of urban flooding. This study aims to better understand rainfall infiltration into a Sustainable Drainage System (SuDS) permeable pavement, compared with an adjacent Green Area of made ground, in relationship to groundwater levels below both areas. Both areas were instrumented with soil water content and matric potential sensors and four shallow boreholes were instrumented with groundwater level sensors. Surface infiltration rates were measured using a double‐ring infiltrometer. Results showed that average infiltration rates of the SuDS (1,925 mm/hr) were significantly higher than the Green Area (56 mm/hr). The SuDS was well designed to transfer rainfall rapidly to the aquifer below, where groundwater levels rapidly rose within 1 hr of a 1 in 30 year event (32.8 mm/hr). In comparison, soil compaction of the made ground Green Area decreased infiltration rates, but still enabled the majority of rainfall events to infiltrate. The aquifer below the Green Area responded more slowly, as lower matrix potentials facilitated water retention in the soil profile, slowing water draining to the aquifer. This work reiterates the importance of ensuring a 1 m separation depth between the base of the SuDS infiltration zone and aquifer depth.

Background Subacute ischemic lesions in intracerebral hemorrhage (ICH) have been hypothesized to result from hypoperfusion. Although studies of cerebral blood flow (CBF) indicate modest hypoperfusion in ICH, these investigations have been limited to early time points. Arterial spin labeling (ASL), a magnetic resonance imaging technique, can be used to measure CBF without a contrast agent. We assessed CBF in patients with ICH using ASL and tested the hypothesis that CBF is related to systolic blood pressure (SBP). Methods and Results In this cross‐sectional study, patients with ICH were assessed with ASL at 48 hours, 7 days, and/or 30 days after onset. Relative CBF (rCBF; ratio of ipsilateral/contralateral perfusion) was measured in the perihematomal regions, hemispheres, border zones, and the perilesional area in patients with diffusion‐weighted imaging hyperintensities. Twenty‐patients (65% men; mean±SD age, 68.5±12.7 years) underwent imaging with ASL at 48 hours (N=12), day 7 (N=6), and day 30 (N=11). Median (interquartile range) hematoma volume was 13.1 (6.3–19.3) mL. Mean±SD baseline SBP was 185.4±25.5 mm Hg. Mean perihematomal rCBF was 0.9±0.2 at 48 hours at all time points. Baseline SBP and other SBP measurements were not associated with a decrease in rCBF in any of the regions of interest (P≥0.111). rCBF did not differ among time points in any of the regions of interest (P≥0.097). Mean perilesional rCBF was 1.04±0.65 and was unrelated to baseline SBP (P=0.105). Conclusions ASL can be used to measure rCBF in patients with acute and subacute ICH. Perihematomal CBF was not associated with SBP changes at any time point. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT00963976.