Live Imaging of the Zebrafish Embryonic Brain by Confocal Microscopy

In this video, we demonstrate the method our lab has developed to analyze the cell shape changes and rearrangements required to bend and fold the developing zebrafish brain (Gutzman et al, 2008). Such analysis affords a new understanding of the underlying cell biology required for development of the 3D structure of the vertebrate brain, and significantly increases our ability to study neural tube morphogenesis. The embryonic zebrafish brain is shaped beginning at 18 hours post fertilization (hpf) as the ventricles within the neuroepithelium inflate. By 24 hpf, the initial steps of neural tube morphogenesis are complete. Using the method described here, embryos at the one cell stage are injected with mRNA encoding membrane-targeted green fluorescent protein (memGFP). After injection and incubation, the embryo, now between 18 and 24 hpf, is mounted, inverted, in agarose and imaged by confocal microscopy. Notably, the zebrafish embryo is transparent making it an ideal system for fluorescent imaging. While our analyses have focused on the midbrain-hindbrain boundary and the hindbrain, this method could be extended for analysis of any region in the zebrafish to a depth of 80-100 μm

Basal constriction : shaping the vertebrate brain

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Biology, February 2011.Cataloged from PDF version of thesis.Includes bibliographical references.Organs are primarily formed from epithelia, polarized sheets of cells with an apical surface facing a lumen and basal surface resting on the underlying extracellular matrix. Cells within a sheet are joined by junctions, and changes in cell shape and size drive epithelial bending and folding during morphogenesis. These shape changes include constriction and expansion of the cell surfaces, elongation or shortening of the apical-basal length, or cell spreading. In this thesis, I present the first description of basal constriction, a process by which cells narrow on their basal surfaces to bend the neuroepithelium. Specifically, I describe morphogenesis of a major conserved bend in the vertebrate neural tube, the midbrain-hindbrain boundary constriction (MHBC). The MHBC forms between 17 and 24 hours post fertilization in zebrafish, concomitant with, but independent of ventricle inflation. Cells shorten to 75% the length of the surrounding cells prior to basal constriction, during which a band of 3-4 cells becomes wedge-shaped. Subsequently, these cells apically expand by twice the width of the surrounding cells. Basal constriction is laminin-dependent, with actin enriched at the basolateral surface of the constricted cells. Wnt5 is highly expressed specifically at the MHBC prior to and during basal constriction and is required for this process. Focal adhesion kinase (FAK) is activated by phosphorylation at the MHBC and is required for basal constriction. FAK activation at the MHBC is dependent upon Wnt5 function. Loss of basal constriction in Wnt5 and FAK loss-of-function embryos can be rescued by inhibiting Gsk3p. These data suggest a novel pathway in which Wnt5 activates FAK in conjunction with the inhibition of Gsk3P to drive basal constriction at the MHBC. This study is the first to describe basal constriction during epithelial morphogenesis and provides mechanistic insights into a newly described cell shape change required for normal brain development.by Ellie Graham Graeden.Ph.D

Rethinking Flood Analytics: Proceedings from the 2017 Flood Analytics Colloquium

This report documents outcomes from the Flood Analytics Colloquium held at the Renaissance Computing Institute (RENCI) in Chapel Hill, NC, on November 7-9, 2017. The Colloquium was sponsored jointly by the Coastal Resilience Center of Excellence (CRC), RENCI, and two organizations within the U.S. Department of Homeland Security’s Science and Technology Directorate: the First Responders Group (FRG) and the Office of University Programs. The overall purpose of the Colloquium was to support the Flood Apex Program, which is managed by the FRG with the goals of reducing fatalities and property losses from future flood events, increasing community resilience to disruptions caused by flooding, and developing better investment strategies to prepare for, respond to, recover from and mitigate against flood hazards. The Colloquium convened a group of approximately 50 selected persons from a variety of sectors and disciplines to explore the future of flood analytics and how it can better address the increasingly complex needs of society in dealing with flood events

A new framework for global data regulation

Under the current regulatory framework for data protections, the protection of human rights writ large and the corresponding outcomes are regulated largely independently from the data and tools that both threaten those rights and are needed to protect them. This separation between tools and the outcomes they generate risks overregulation of the data and tools themselves when not linked to sensitive use cases. In parallel, separation risks under-regulation if the data can be collected and processed under a less-restrictive framework, but used to drive an outcome that requires additional sensitivity and restrictions. A new approach is needed to support differential protections based on the genuinely high-risk use cases within each sector. Here, we propose a regulatory framework designed to apply not to specific data or tools themselves, but to the outcomes and rights that are linked to the use of these data and tools in context. This framework is designed to recognize, address, and protect a broad range of human rights, including privacy, and suggests a more flexible approach to policy making that is aligned with current engineering tools and practices. We test this framework in the context of open banking and describe how current privacy-enhancing technologies and other engineering strategies can be applied in this context and that of contract tracing applications. This approach for data protection regulations more effectively builds on existing engineering tools and protects the wide range of human rights defined by legislation and constitutions around the globe.Comment: 15 pages, 2 figure

Law, criminalisation and HIV in the world: have countries that criminalise achieved more or less successful pandemic response?

How do choices in criminal law and rights protections affect disease-fighting efforts? This long-standing question facing governments around the world is acute in the context of pandemics like HIV and COVID-19. The Global AIDS Strategy of the last 5 years sought to prevent mortality and HIV transmission in part through ensuring people living with HIV (PLHIV) knew their HIV status and could suppress the HIV virus through antiretroviral treatment. This article presents a cross-national ecological analysis of the relative success of national AIDS responses under this strategy, where laws were characterised by more or less criminalisation and with varying rights protections. In countries where same-sex sexual acts were criminalised, the portion of PLHIV who knew their HIV status was 11% lower and viral suppression levels 8% lower. Sex work criminalisation was associated with 10% lower knowledge of status and 6% lower viral suppression. Drug use criminalisation was associated with 14% lower levels of both. Criminalising all three of these areas was associated with approximately 18%-24% worse outcomes. Meanwhile, national laws on non-discrimination, independent human rights institutions and gender-based violence were associated with significantly higher knowledge of HIV status and higher viral suppression among PLHIV. Since most countries did not achieve 2020 HIV goals, this ecological evidence suggests that law reform may be an important tool in speeding momentum to halt the pandemic

Basal constriction during midbrain–hindbrain boundary morphogenesis is mediated by Wnt5b and focal adhesion kinase

Basal constriction occurs at the zebrafish midbrain-hindbrain boundary constriction (MHBC) and is likely a widespread morphogenetic mechanism. 3D reconstruction demonstrates that MHBC cells are wedge-shaped, and initially constrict basally, with subsequent apical expansion. wnt5b is expressed in the MHB and is required for basal constriction. Consistent with a requirement for this pathway, expression of dominant negative Gsk3β overcomes wnt5b knockdown. Immunostaining identifies focal adhesion kinase (Fak) as active in the MHB region, and knockdown demonstrates Fak is a regulator of basal constriction. Tissue specific knockdown further indicates that Fak functions cell autonomously within the MHBC. Fak acts downstream of wnt5b, suggesting that Wnt5b signals locally as an early step in basal constriction and acts together with more widespread Fak activation. This study delineates signaling pathways that regulate basal constriction during brain morphogenesis.National Science Foundation (U.S.). Graduate Research Fellowship (Grant 1122374)National Science Foundation (U.S.) (Grant 1258087

Alignment between first edition JEE, SPAR, and WHO Global Health Observatory data.

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Overall and per capita costs by World Bank income group.

Per capita costs reflect the costs of investments over a period of five years. All costs reported in approximate 2021 USD, and rounded to the nearest hundred million, as such, numbers reported may not sum precisely to total.</p