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1. A field-deployable diagnostic assay for the visual detection of misfolded prions

   https://doi.org/10.1038/s41598-022-16323-y  

   Christenson, Peter R.; Li, Manci; Rowden, Gage; Schwabenlander, Marc D.; Wolf, Tiffany M.; Oh, Sang-Hyun; Larsen, Peter A. (December 2022, Scientific Reports)

   Abstract Diagnostic tools for the detection of protein-misfolding diseases (i.e., proteopathies) are limited. Gold nanoparticles (AuNPs) facilitate sensitive diagnostic techniques via visual color change for the identification of a variety of targets. In parallel, recently developed quaking-induced conversion (QuIC) assays leverage protein-amplification and fluorescent signaling for the accurate detection of misfolded proteins. Here, we combine AuNP and QuIC technologies for the visual detection of amplified misfolded prion proteins from tissues of wild white-tailed deer infected with chronic wasting disease (CWD), a prion disease of cervids. Our newly developed assay, MN-QuIC, enables both naked-eye and light-absorbance measurements for detection of misfolded prions. MN-QuIC leverages basic laboratory equipment that is cost-effective and portable, thus facilitating real-time prion diagnostics across a variety of settings. In addition to laboratory-based tests, we deployed to a rural field-station in southeastern Minnesota and tested for CWD on site. We successfully demonstrated that MN-QuIC is functional in a non-traditional laboratory setting by performing a blinded analysis in the field and correctly identifying all CWD positive and CWD not-detected deer at the field site in 24 h, thus documenting the portability of the assay. White-tailed deer tissues used to validate MN-QuIC included medial retropharyngeal lymph nodes, parotid lymph nodes, and palatine tonsils. Importantly, all of the white-tailed deer (n = 63) were independently tested using ELISA, IHC, and/or RT-QuIC technologies and results secured with MN-QuIC were 95.7% and 100% consistent with these tests for positive and non-detected animals, respectively. We hypothesize that electrostatic forces help govern the AuNP/prion interactions and conclude that MN-QuIC has great potential for sensitive, field-deployable diagnostics for CWD, with future potential diagnostic applications for a variety of proteopathies. 

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2. Exposing and Circumventing SNI-based QUIC Censorship of the Great Firewall of China

   Zohaib, Ali; Zao, Qiang; Sippe, Jackson; Alaraj, Abdulrahman; Houmansadr, Amir; Durumeric, Zakir; Wustrow, Eric (August 2025, USENIX Security Symposium)

   Despite QUIC handshake packets being encrypted, the Great Firewall of China (GFW) has begun blocking QUIC connections to specific domains since April 7, 2024. In this work, we measure and characterize the GFW’s censorship of QUIC to understand how and what it blocks. Our measurements reveal that the GFW decrypts QUIC Initial packets at scale, applies heuristic filtering rules, and uses a blocklist distinct from its other censorship mechanisms. We expose a critical flaw in this new system: the computational overhead of decryption reduces its effectiveness under moderate traffic loads. We also demonstrate that this censorship mechanism can be weaponized to block UDP traffic between arbitrary hosts in China and the rest of the world. We collaborate with various open-source communities to integrate circumvention strategies into a leading web browser, the quic-go library, and all major QUIC-based circumvention tools. 

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3. A Security Model and Fully Verified Implementation for the IETF QUIC Record Layer

   Delignat-Lavaud, Antoine; Fournet, Cédric; Parno, Bryan; Protzenko, Jonathan; Ramananandro, Tahina; Bosamiya, Jay; Lallemand, Joseph; Rakotonirina, Itsaka; Zhou, Yi (May 2021, Proceedings of the IEEE Symposium on Security and Privacy)

   null (Ed.)

   We investigate the security of the QUIC record layer, as standardized by the IETF in draft version 30. This version features major differences compared to Google's original protocol and prior IETF drafts. We model packet and header encryption, which uses a custom construction for privacy. To capture its goals, we propose a security definition for authenticated encryption with semi-implicit nonces. We show that QUIC uses an instance of a generic construction parameterized by a standard AEAD-secure scheme and a PRF-secure cipher. We formalize and verify the security of this construction in F*. The proof uncovers interesting limitations of nonce confidentiality, due to the malleability of short headers and the ability to choose the number of least significant bits included in the packet counter. We propose improvements that simplify the proof and increase robustness against strong attacker models. In addition to the verified security model, we also give concrete functional specification for the record layer, and prove that it satisfies important functionality properties (such as successful decryption of encrypted packets) after fixing more errors in the draft. We then provide a high-performance implementation of the record layer that we prove to be memory safe, correct with respect to our concrete specification (inheriting its functional correctness properties), and secure with respect to our verified model. To evaluate this component, we develop a provably-safe implementation of the rest of the QUIC protocol. Our record layer achieves nearly 2 GB/s throughput, and our QUIC implementation's performance is within 21% of an unverified baseline. 

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4. Does Quantum Interference Control of injected Photocurrents Produce a Current or Voltage?

   https://doi.org/10.1364/CLEO_AT.2024.JTu2A.134  

   Gong, Yiming; Cundiff, Steven T (January 2024, Optica Publishing Group)

   We address the question “Does Quantum Interference Control (QuIC) of injected Photocurrents Produces a Current or Voltage?” by studying the dependence on external resistance for Schottky- and Ohmic- contact devices, resolving a long-standing puzzle. 

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5. Internet Connection Splitting: What’s Old is New Again

   Yuan, Gina; Rossman, Thea; Winstein, Keith (July 2025, USENIX Association)

   Altınbüken, Deniz; Stutsman, Ryan (Ed.)

   In the 1990s, many networks deployed performance-enhancing proxies (PEPs) that transparently split TCP connections to aid performance, especially over lossy, long-delay paths. Two recent developments have cast doubts on their relevance: the BBR congestion-control algorithm, which de-emphasizes loss as a congestion signal, and the QUIC transport protocol, which prevents transparent connection-splitting yet empirically matches or exceeds TCP’s performance in wide deployment, using the same congestion control. In light of this, are PEPs obsolete? This paper presents a range of emulation measurements indicating: “probably not.” While BBR’s original 2016 version didn’t benefit markedly from connection-splitting, more recent versions of BBR do and, in some cases, even more so than earlier “loss-based” congestion-control algorithms. We also find that QUIC implementations of the “same” congestion-control algorithms vary dramatically and further differ from those of Linux TCP—frustrating head-to-head comparisons. Notwithstanding their controversial nature, our results suggest that PEPs remain relevant to Internet performance for the foreseeable future. 

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