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Addressing the optimization problem during the simultaneous energy and information transmission stage in the simultaneous wireless information and power transfer (SWIPT), an optimal energy efficiency strategy based on mmWave cooperative communication small cell is proposed to maximize the link energy efficiency. This strategy, under the joint constraints of minimum link transmission rate and minimum collected energy, employs a power splitting mode at the receding end of energy-constrained user devices. By optimizing transmit power control and power splitting factors, it aims to maximize the systems link energy efficiency. Recognizing the original problem as a nonconvex fractional programming problem with NP-hard characteristics, the Dinkelbach method is utilized to transform the objective function into a convex optimization problem that is easier to solve. An iterative algorithm is designed to find the optimal solution through cross iterations. Simulation results demonstrate that the proposed strategy outperforms traditional power control methods and maximum transmit power approaches in optimizing system energy efficiency. [ABSTRACT FROM AUTHOR]

The white-back planthopper (WBPH), Sogatella furcifera, is a major rice pest in China and in some other rice-growing countries of Asia. The extensive use of pesticides has resulted in severe resistance of S. furcifera to variety of chemical insecticides. Sulfoxaflor is a new diamide insecticide that acts on nicotinic acetylcholine receptors (nAChRs) in insects. The aim of this study was to explore the key genes related to the development of resistance to sulfoxaflor in S. furcifera and to verify their functions. Transcriptomes were compared between white-back planthoppers from a susceptible laboratory strain (Sus-Lab) and Sus-Lab screened with the sublethal LC25 dose of sulfoxaflor for six generations (SF-Sel). Two P450 genes (CYP6FD1 and CYP4FD2) and three transcription factors (NlE78sf, C2H2ZF1 and C2H2ZF3) with upregulated expression verified by qRT-PCR were detected in the Sus-Lab and SF-Sel strains. The functions of CYP6FD1 and CYP4FD2 were analyzed by RNA interference, and the relative normalized expressions of CYP6FD1 and CYP4FD2 in the SF-Sel population were lower than under dsGFP treatment after dsRNA injection. Moreover, the mortality rates of SF-Sel population treated with the LC50 concentration of sulfoxaflor after the injecting of dsRNA targeting CYP6FD1 and CYP4FD2 were significantly higher than in the dsGFP group from 72 h to 96 h (p < 0.05), and mortality in the CYP6FD1 knockdown group was clearly higher than that of the CYP4FD2 knockdown group. The interaction between the tertiary structures of CYP6FD1 and CYP4FD2 and sulfoxaflor was also predicted, and CYP6FD1 showed a stronger metabolic ability to process sulfoxaflor. Therefore, overexpression of CYP6FD1 and CYP4FD2 may be one of the primary factors in the development of sulfoxaflor resistance in S. furcifera.

Wireless sensor networks (WSN) are used extensively in various important areas of agriculture. Many of the associated activities involve the transmission of data or control commands through gateways that connect the servers to 3G networks. In this paper, we investigate the issues caused by Radio Resource Control (RRC) state transitions, which introduce high sudden delays in TCP packets. The packets that are subjected to these delays are then usually retransmitted because of timeouts. Further, the recently recommended TCP retransmission timer settings (RFC6298) reduce the initial retransmission timeout (RTO) from the previous three seconds to one second, further exacerbating the phenomenon of SYN packet retransmission, because a SYN packet is always the first packet to trigger the RRC state to change. We conduct a number of tests to examine the phenomenon and analyze the effect of this spurious retransmission timeout. Consequently, we propose recommendations for improvement. [ABSTRACT FROM AUTHOR]

Partially blurred images caused by motion or out of focus are common in life, we need to detect and segment blurred image region when doing some multimedia analyzing tasks. As for the problem of blurred region detection and segmentation of partially blurred images, we propose a method based on singular value decomposition and image matting is presented in this paper. Making use of the different changes of image blurred regions and clear regions under a low-pass filtering, partially blurred image is firstly partitioned into patches and each image patch is re-blurred by a Gaussian function, then a trimap is got after comparing the singular value feature difference of the patches to distinguish blurred regions and clear regions. Secondly, a image matting technique is combined with the trimap to automatically segment blurred regions from the partially blurred images. Experiments show that this method can detect and segment the blurred regions accurately. [ABSTRACT FROM AUTHOR]

The Wittig olefination of trifluromethyl ketones and allylic carbonates mediated by tributylphosphine was realized to give corresponding trifluoromethyl dienes in good yields with excellent E-selectivities. [ABSTRACT FROM AUTHOR]

The cinchona alkaloid-catalyzed γ-amination of α,β-unsaturated acyl chlorides with azodicarboxylates to give the corresponding dihydropyridazinones in good yields with high enantioselectivities has been developed. Reductive ring opening of the dihydropyridazinones afforded series of cyclic and acyclic γ-amino acid derivatives in good yields with high enantiopurity [ABSTRACT FROM AUTHOR]

Similar to traditional wireless sensor networks (WSN), the nodes only have limited memory and energy in low-duty-cycle sensor networks (LDC-WSN). However, different from WSN, the nodes in LDC-WSN often sleep most of their time to preserve their energies. The sleeping feature causes serious data transmission delay. However, each source node that has sensed data needs to quickly disseminate its data to other nodes in the network for redundant storage. Otherwise, data would be lost due to its source node possibly being destroyed by outer forces in a harsh environment. The quick dissemination requirement produces a contradiction with the sleeping delay in the network. How to quickly disseminate all the source data to all the nodes with limited memory in the network for effective preservation is a challenging issue. In this paper, a low-latency and energy-efficient data preservation mechanism in LDC-WSN is proposed. The mechanism is totally distributed. The data can be disseminated to the network with low latency by using a revised probabilistic broadcasting mechanism, and then stored by the nodes with LT (Luby Transform) codes, which are a famous rateless erasure code. After the process of data dissemination and storage completes, some nodes may die due to being destroyed by outer forces. If a mobile sink enters the network at any time and from any place to collect the data, it can recover all of the source data by visiting a small portion of survived nodes in the network. Theoretical analyses and simulation results show that our mechanism outperforms existing mechanisms in the performances of data dissemination delay and energy efficiency.