Identity-based encryption (IBE) is an exciting alternative to public-key encryption, as IBE eliminates the need for a Public Key Infrastructure (PKI). Any setting, PKI-or identity-based, must provide a means to revoke users from the system. Efficient revocation is a well-studied problem in the traditional PKI setting. However in the setting of IBE, there has been little work on studying the revocation mechanisms. The most practical solution requires the senders to also use time periods when encrypting, and all the receivers (regardless of whether their keys have been compromised or not) to update their private keys regularly by contacting the trusted authority. We note that this solution does not scale well -as the number of users increases, the work on key updates becomes a bottleneck. We propose an IBE scheme that significantly improves key-update efficiency on the side of the trusted party (from linear to logarithmic in the number of users), while staying efficient for the users. Our scheme builds on the ideas of the Fuzzy IBE primitive and binary tree data structure, and is provably secure.

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Summary To meet the ever‐increasing demand for animal protein, aquaculture continuously requires new techniques to increase the production yield. However, with every step towards intensification of aquaculture practices, there is an increase in stress level on the animal as well as on the environment. Feeding practices in aqua farming usually plays an important role, and the addition of various additives to a balanced feed formula to achieve better growth is a common practice among the fish and shrimp culturists. Probiotics, also known as ‘bio‐friendly agents’, such as LAB (Lactobacillus), yeasts and Bacillus sp., can be introduced into the culture environment to control and compete with pathogenic bacteria as well as to promote the growth of the cultured organisms. In addition, probiotics are non‐pathogenic and non‐toxic micro‐organisms, having no undesirable side effects when administered to aquatic organisms. Probiotics are also known to play an important role in developing innate immunity among the fishes, and hence help them to fight against any pathogenic bacterias as well as against environmental stressors. The present review is a brief but informative compilation of the different essential and desirable traits of probiotics, their mode of action and their useful effects on fishes. The review also highlights the role of probiotics in helping the fishes to combat against the different physical, chemical and biological stress.

The US Department of Transportation (US-DOT) issued a proposed rule on January 12th, 2017 to mandate vehicle-to-vehicle (V2V) safety communications in light vehicles in the US. Cybersecurity and privacy are major challenges for such a deployment. The authors present a Security Credential Management System (SCMS) for vehicle-to-everything (V2X) communications in this paper, which has been developed by the Crash Avoidance Metrics Partners LLC (CAMP) under a Cooperative Agreement with the USDOT. This system design is currently transitioning from research to Proof-of-Concept, and is a leading candidate to support the establishment of a nationwide Public Key Infrastructure (PKI) for V2X security. It issues digital certificates to participating vehicles and infrastructure nodes for trustworthy communications among them, which is necessary for safety and mobility applications that are based on V2X communications. The SCMS supports four main use cases, namely bootstrapping, certificate provisioning, misbehavior reporting and revocation. The main design goal is to provide both security and privacy to the largest extent reasonable and possible. To achieve a reasonable level of privacy in this context, vehicles are issued pseudonym certificates, and the generation and provisioning of those certificates are divided among multiple organizations. Given the large number of pseudonym certificates per vehicle, one of the main challenges is to facilitate efficient revocation of misbehaving or malfunctioning vehicles, while preserving privacy against attacks from insiders. The proposed SCMS supports all identified V2X use-cases and certificate types necessary for V2X communication security. This paper is based upon work supported by the U.S. Department of Transportation. Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the Authors ("we") and do not necessarily reflect the view of the U.S. Department of Transportation.• Step 3. The MA makes a request (signed) to the PCA to map the linkage value lv of the identified

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Tailoring the formation of dynamic and static excimers in a C3-symmetric architecture led to efficient generation of white light and sensitive detection of Fe3+ and Al3+ in a single molecular platform.

The excited-state intramolecular proton transfer (ESIPT)-based molecular probes have drawn significant attention owing to their environment-sensitive fluorescence properties, large Stokes shift, and emerged as building blocks for the development of molecular sensors and switches. However, most of the ESIPT-based fluorophores exhibit weak emission in the solid state limiting the scope of real-time applications. Addressing such issues, herein, we presented a C 3 symmetric-like molecular architecture employing a simple one-step Schiff base condensation between triaminoguanidinium chloride and 3,5-di-tert-butyl-2-hydroxybenzaldehyde (TGHB). The temperature-dependent fluorescence studies including at 77 K indicated the strong emission from the keto tautomer compared to that of the enol tautomer. The facile ESIPT in TGHB in the solid-state led to a remarkable enhancement of fluorescence quantum yield of 1600 times compared to that of the solution (λ em = 545 nm) by restricting the intramolecular rotation and subsequently suppressing the nonradiative deactivation. The excited-state processes were further elucidated through time-resolved fluorescence measurements. TGHB exhibited turn on−off fluorescence upon exposure to acid/base vapor in the form of a powder as well as a transparent, freestanding thin film. A rewritable and erasable fluorescent platform was demonstrated using TGHB as molecular ink, which offers a potential testbed for performing "write-erase-write" cycles multiple times. In addition, TGHB, possessing multiple binding sites (O and N donors) involving the central core of the triaminoguanidinium cation displayed selective turn-on fluorescence with Zn 2+ . The structure−property relationship revealed in the present study provides insight into the development of novel cost-effective multifunctional materials, which are promising for stimuli-responsive molecular switches.

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