AMP-activated protein kinase (AMPK) is a critical regulator of cellular and whole-body energy homeostasis. Twelve AMPK-related kinases (ARKs; BRSK1, BRSK2, NUAK1, NUAK2, QIK, QSK, SIK, MARK1, MARK2, MARK3, MARK4, and MELK) have been identified recently. These kinases show a similar structural organization, including an N-terminal catalytic domain, followed by a ubiquitin-associated domain and a C-terminal spacer sequence, which in some cases also contains a kinase-associated domain 1. Eleven of the ARKs are phosphorylated and activated by the master upstream kinase liver kinase B1. However, most of these ARKs are largely unknown, and the NUAK family seems to have different regulations and functions. This review contains a brief discussion of the NUAK family including the specific characteristics of NUAK1 and NUAK2. Key Words" AMP-activated protein kinase (AMPK)" AMPK-related kinase" sucrose-non-fermenting protein kinase (SNF1)/AMPKrelated kinase (SNARK)Journal of Molecular Endocrinology (2013) 51, R15-R22

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Owing to its lightweight and easiness, the message queue telemetry transport (MQTT) has become one of the most popular communication protocols in the internet-of-things (IoT). However, the security supports in the MQTT are very weak. In this paper, we systematically examine the security requirements of a MQTT-based IoT system, identify the gap between the requirements and the supported functions, and design a security-enhanced MQTT framework. The framework facilitates device authentication, key agreement, and policy authorisation. Additionally, it is desirable that any MQTT-security enhancements should be compatible with existent MQTT Application Programming Interfaces (API). We propose a two-phase authentication approach that can smoothly integrate secure key agreement schemes with the current MQTT-API. To evaluate its effectiveness and efficiency, we implement prototype. Compared to its counterparts, the results show the merits of improved communication performance, MQTT-API compliance, and security robustness.

SUMMARYMany applications of wireless sensor network (WSN) require secure data communications, especially in a hostile environment. In order to protect the sensitive data and the sensor readings, secret keys should be used to encrypt the exchanged messages between communicating nodes. Traditional asymmetric key cryptosystems are infeasible in WSNs due to the extremely low capacity and constrained resources at each senor node. Recently proposed protocols are either vulnerable to the large-scale node capture attacks or lack of performance scalability in terms of storage, communication and computation costs. To address these limitations, we study the key pre-distribution schemes in this paper and propose a new one with all of the following properties which are particularly beneficial to the large-scale resource-constrained WSNs: (1) it completely defends against the node capture attacks, (2) it provides full connectivity of the network, and (3) it reduces the storage and communication overhead significantly compared with the other proposals.