72 research outputs found

    Following Intellectual Genealogies: The Construction of Mare Liberum and Mare Clausum, 1603-1652

    Get PDF
    This thesis traces the early modern intellectual lineages of Mare Liberum, the idea that the ocean should be common to all, and Mare Clausum, the idea that the ocean can be owned. It examines the genesis of Mare Liberum in jurist Hugo Grotius’s Mare Liberum as well as the genesis of Mare Clausum in eminent and well-developed responses to Grotius: William Welwod’s De Dominio Maris, Serafim de Freitas’s Do Justo Império Asiático dos Portugueses, and John Selden’s Mare Clausum: Of The Dominion, or, Ownership of the Sea. In bringing each theorist into dialogue and debate with the others, this thesis bridges language barriers and demonstrates the importance of understanding each theorist in his context. Ultimately, it argues that the continued existence of Mare Liberum and Mare Clausum as distinct “genealogies” of ideas centered on the fact that Grotius justified Mare Liberum on a philosophical level while jurists like Welwod, de Freitas, and Selden justified Mare Clausum on a practical level. With justifications resting in two separate spheres – one regarding what the nature of the ocean was and one regarding what the state of the ocean ought to have been – Mare Liberum and Mare Clausum were unable to speak discursively to one another. In the early seventeenth century, Mare Clausum and Mare Liberum were ships passing in the night

    NASA SpaceCube Edge TPU SmallSat Card for Autonomous Operations and Onboard Science-Data Analysis

    Get PDF
    Using state-of-the-art artificial intelligence (AI)frameworks onboard spacecraft is challenging because common spacecraft processors cannot provide comparable performance to data centers with server-grade CPUs and GPUs available for terrestrial applications and advanced deep-learning networks. This limitation makes small, low-power AI microchip architectures, such as the Google Coral Edge Tensor Processing Unit (TPU), attractive for space missions where the application-specific design enables both high-performance and power-efficient computing for AI applications. To address these challenging considerations for space deployment, this research introduces the design and capabilities of a CubeSat-sized Edge TPU-based co-processor card, known as the SpaceCube Low-power Edge Artificial Intelligence Resilient Node (SC-LEARN). This design conforms to NASA’s CubeSat Card Specification (CS2) for integration into next-generation SmallSat and CubeSat systems. This paper describes the overarching architecture and design of the SC-LEARN, as well as, the supporting test card designed for rapid prototyping and evaluation. The SC-LEARN was developed with three operational modes: (1) a high-performance parallel-processing mode,(2)a fault-tolerant mode for onboard resilience, and (3) a power-saving mode with cold spares. Importantly, this research also elaborates on both training and quantization of TensorFlow models for the SC-LEARN for use onboard with representative, open-source datasets. Lastly, we describe future research plans, including radiation-beam testing and flight demonstration

    NF-M is an essential target for the myelin-directed “outside-in” signaling cascade that mediates radial axonal growth

    Get PDF
    Neurofilaments are essential for acquisition of normal axonal calibers. Several lines of evidence have suggested that neurofilament-dependent structuring of axoplasm arises through an “outside-in” signaling cascade originating from myelinating cells. Implicated as targets in this cascade are the highly phosphorylated KSP domains of neurofilament subunits NF-H and NF-M. These are nearly stoichiometrically phosphorylated in myelinated internodes where radial axonal growth takes place, but not in the smaller, unmyelinated nodes. Gene replacement has now been used to produce mice expressing normal levels of the three neurofilament subunits, but which are deleted in the known phosphorylation sites within either NF-M or within both NF-M and NF-H. This has revealed that the tail domain of NF-M, with seven KSP motifs, is an essential target for the myelination-dependent outside-in signaling cascade that determines axonal caliber and conduction velocity of motor axons

    NASA SpaceCube Next-Generation Artificial-Intelligence Computing for STP-H9-SCENIC on ISS

    Get PDF
    Recently, Artificial Intelligence (AI) and Machine Learning (ML) capabilities have seen an exponential increase in interest from academia and industry that can be a disruptive, transformative development for future missions. Specifically, AI/ML concepts for edge computing can be integrated into future missions for autonomous operation, constellation missions, and onboard data analysis. However, using commercial AI software frameworks onboard spacecraft is challenging because traditional radiation-hardened processors and common spacecraft processors cannot provide the necessary onboard processing capability to effectively deploy complex AI models. Advantageously, embedded AI microchips being developed for the mobile market demonstrate remarkable capability and follow similar size, weight, and power constraints that could be imposed on a space-based system. Unfortunately, many of these devices have not been qualified for use in space. Therefore, Space Test Program - Houston 9 - SpaceCube Edge-Node Intelligent Collaboration (STP-H9-SCENIC) will demonstrate inflight, cutting-edge AI applications on multiple space-based devices for next-generation onboard intelligence. SCENIC will characterize several embedded AI devices in a relevant space environment and will provide NASA and DoD with flight heritage data and lessons learned for developers seeking to enable AI/ML on future missions. Finally, SCENIC also includes new CubeSat form-factor GPS and SDR cards for guidance and navigation

    A dualistic model of primary anal canal adenocarcinoma with distinct cellular origins, etiologies, inflammatory microenvironments and mutational signatures: implications for personalised medicine.

    Get PDF
    Primary adenocarcinoma of the anal canal is a rare and aggressive gastrointestinal disease with unclear pathogenesis. Because of its rarity, no clear clinical practice guideline has been defined and a targeted therapeutic armamentarium has yet to be developed. The present article aimed at addressing this information gap by in-depth characterising the anal glandular neoplasms at the histologic, immunologic, genomic and epidemiologic levels. In this multi-institutional study, we first examined the histological features displayed by each collected tumour (n = 74) and analysed their etiological relationship with human papillomavirus (HPV) infection. The intratumoural immune cell subsets (CD4, CD8, Foxp3), the expression of immune checkpoints (PD-1, PD-L1), the defect in mismatch repair proteins and the mutation analysis of multiple clinically relevant genes in the gastrointestinal cancer setting were also determined. Finally, the prognostic significance of each clinicopathological variable was assessed. Phenotypic analysis revealed two region-specific subtypes of anal canal adenocarcinoma. The significant differences in the HPV status, density of tumour-infiltrating lymphocytes, expression of immune checkpoints and mutational profile of several targetable genes further supported the separation of these latter neoplasms into two distinct entities. Importantly, anal gland/transitional-type cancers, which poorly respond to standard treatments, displayed less mutations in downstream effectors of the EGFR signalling pathway (i.e., KRAS and NRAS) and demonstrated a significantly higher expression of the immune inhibitory ligand-receptor pair PD-1/PD-L1 compared to their counterparts arising from the colorectal mucosa. Taken together, the findings reported in the present article reveal, for the first time, that glandular neoplasms of the anal canal arise by HPV-dependent or independent pathways. These etiological differences leads to both individual immune profiles and mutational landscapes that can be targeted for therapeutic benefits

    Deciphering the Multifactorial Susceptibility of Mucosal Junction Cells to HPV Infection and Related Carcinogenesis

    No full text
    Human papillomavirus (HPV)-induced neoplasms have long been considered to originate from viral infection of the basal cell layer of the squamous mucosa. However, this paradigm has been recently undermined by accumulating data supporting the critical role of a discrete population of squamo-columnar (SC) junction cells in the pathogenesis of cervical (pre)cancers. The present review summarizes the current knowledge on junctional cells, discusses their high vulnerability to HPV infection, and stresses the potential clinical/translational value of the novel dualistic model of HPV-related carcinogenesis
    corecore