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As service providers are moving to the cloud, users are forced to provision sensitive data to the cloud. Confidential computing leverages hardware Trusted Execution Environment (TEE) to protect data in use, no longer requiring users’ trust to the cloud. The emerging service model, Confidential Computing as a Service (CCaaS), is adopted by service providers to offer service similar to the Function-as-a-Serivce manner. However, privacy concerns are raised in CCaaS, especially in multi-user scenarios. CCaaS need to assure the data providers that the service does not leak their privacy to any unauthorized parties and clear their data after the service. To address such privacy concerns with security guarantees, we first formally define the security objective, Proof of Being Forgotten (PoBF), and prove under which security constraints PoBF can be satisfied. Then, these constraints serve as guidelines in the implementation of the PoBF-compliant Framework (PoCF). PoCF consists of a generic library for different hardware TEEs, CCaaS prototype enclaves, and a verifier to prove PoBF-compliance. PoCF leverages Rust’s robust type system and security features, to construct a verified state machine with privacy-preserving contracts. Last, the experiment results show that the protections introduced by PoCF incur minor runtime performance overhead. 

In a conjugated polymer‐based single‐particle heterojunction, stochastic fluctuations of the photogenerated hole population lead to spontaneous fluorescence switching. We found that 405 nm irradiation can induce charge recombination and activate the single‐particle emission. Based on these phenomena, we developed a novel class of semiconducting polymer dots that can operate in two superresolution imaging modes. The spontaneous switching mode offers efficient imaging of large areas, with <10 nm localization precision, while the photoactivation/deactivation mode offers slower imaging, with further improved localization precision (ca. 1 nm), showing advantages in resolving small structures that require high spatial resolution. Superresolution imaging of microtubules and clathrin‐coated pits was demonstrated, under both modes. The excellent localization precision and versatile imaging options provided by these nanoparticles offer clear advantages for imaging of various biological systems.

 

In a conjugated polymer‐based single‐particle heterojunction, stochastic fluctuations of the photogenerated hole population lead to spontaneous fluorescence switching. We found that 405 nm irradiation can induce charge recombination and activate the single‐particle emission. Based on these phenomena, we developed a novel class of semiconducting polymer dots that can operate in two superresolution imaging modes. The spontaneous switching mode offers efficient imaging of large areas, with <10 nm localization precision, while the photoactivation/deactivation mode offers slower imaging, with further improved localization precision (ca. 1 nm), showing advantages in resolving small structures that require high spatial resolution. Superresolution imaging of microtubules and clathrin‐coated pits was demonstrated, under both modes. The excellent localization precision and versatile imaging options provided by these nanoparticles offer clear advantages for imaging of various biological systems.

 

Impaired glucose metabolism in diabetes causes severe acute and long‐term complications, making real‐time detection of blood glucose indispensable for diabetic patients. Existing continuous glucose monitoring systems are unsuitable for long‐term clinical glycemic management due to poor long‐term stability. Polymer dot (Pdot) glucose transducers are implantable optical nanosensors that exhibit excellent brightness, sensitivity, selectivity, and biocompatibility. Here, it is shown that hydrogen peroxide—a product of glucose oxidation in Pdot glucose sensors—degrades sensor performance via photobleaching, reduces glucose oxidase activity, and generates cytotoxicity. By adding catalase to a glucose oxidase‐based Pdot sensor to create an enzymatic cascade, the hydrogen peroxide product of glucose oxidation is rapidly decomposed by catalase, preventing its accumulation and improving the sensor's photostability, enzymatic activity, and biocompatibility. Thus, a next‐generation Pdot glucose transducer with a multienzyme reaction system (Pdot–GOx/CAT) that provides excellent sensing characteristics as well as greater detection system stability is presented. Pdot glucose transducers that incorporate this enzymatic cascade to eliminate hydrogen peroxide will possess greater long‐term stability for improved continuous glucose monitoring in diabetic patients.