Research on optimization and improvement of agricultural supply chain model under the background of “Internet Plus”

“Internet +” technology brings new opportunities for the optimization of agricultural product supply chain model, and constantly promotes the transformation and upgrading of agricultural product production, processing, sales, transportation and other links. With the development of intelligent and digital technology, the online sales of agricultural products have been more optimized and developed. Under the background of “Internet +”, the supply chain of agricultural products should make use of new technologies on the basis of traditional, provide a good environment for the modernization of agricultural product sales, and form an effi cient supply chain system. Based on this, this paper will focus on the optimization and improvement of agricultural product supply chain model under the background of “Internet +”

AI-Oriented Two-Phase Multi-Factor Authentication in SAGINs: Prospects and Challenges

Space-air-ground integrated networks (SAGINs), which have emerged as an expansion of terrestrial networks, provide flexible access, ubiquitous coverage, high-capacity backhaul, and emergency/disaster recovery for mobile users (MUs). While the massive benefits brought by SAGIN may improve the quality of service, unauthorized access to SAGIN entities is potentially dangerous. At present, conventional crypto-based authentication is facing challenges, such as the inability to provide continuous and transparent protection for MUs. In this article, we propose an AI-oriented two-phase multi-factor authentication scheme (ATMAS) by introducing intelligence to authentication. The satellite and network control center collaborate on continuous authentication, while unique spatial-temporal features, including service features and geographic features, are utilized to enhance the system security. Our further security analysis and performance evaluations show that ATMAS has proper security characteristics which can meet various security requirements. Moreover, we shed light on lightweight and efficient authentication mechanism design through a proper combination of spatial-temporal factors.Comment: Accepted by IEEE Consumer Electronics Magazin

Accelerated partial separable model using dimension-reduced optimization technique for ultra-fast cardiac MRI

Objective. Imaging dynamic object with high temporal resolution is challenging in magnetic resonance imaging (MRI). Partial separable (PS) model was proposed to improve the imaging quality by reducing the degrees of freedom of the inverse problem. However, PS model still suffers from long acquisition time and even longer reconstruction time. The main objective of this study is to accelerate the PS model, shorten the time required for acquisition and reconstruction, and maintain good image quality simultaneously. Approach. We proposed to fully exploit the dimension reduction property of the PS model, which means implementing the optimization algorithm in subspace. We optimized the data consistency term, and used a Tikhonov regularization term based on the Frobenius norm of temporal difference. The proposed dimension-reduced optimization technique was validated in free-running cardiac MRI. We have performed both retrospective experiments on public dataset and prospective experiments on in-vivo data. The proposed method was compared with four competing algorithms based on PS model, and two non-PS model methods. Main results. The proposed method has robust performance against shortened acquisition time or suboptimal hyper-parameter settings, and achieves superior image quality over all other competing algorithms. The proposed method is 20-fold faster than the widely accepted PS+Sparse method, enabling image reconstruction to be finished in just a few seconds. Significance. Accelerated PS model has the potential to save much time for clinical dynamic MRI examination, and is promising for real-time MRI applications.Comment: 23 pages, 11 figures. Accepted as manuscript on Physics in Medicine & Biolog

Inhibition of G1P3 expression found in the differential display study on respiratory syncytial virus infection

<p>Abstract</p> <p>Background</p> <p>Respiratory syncytial virus (RSV) is the leading viral pathogen associated with bronchiolitis and lower respiratory tract disease in infants and young children worldwide. The respiratory epithelium is the primary initiator of pulmonary inflammation in RSV infections, which cause significant perturbations of global gene expression controlling multiple cellular processes. In this study, differential display reverse transcription polymerase chain reaction amplification was performed to examine mRNA expression in a human alveolar cell line (SPC-A1) infected with RSV.</p> <p>Results</p> <p>Of the 2,500 interpretable bands on denaturing polyacrylamide gels, 40 (1.6%) cDNA bands were differentially regulated by RSV, in which 28 (70%) appeared to be upregulated and another 12 (30%) appeared to be downregulated. Forty of the expressed sequence tags (EST) were isolated, and 20 matched homologs in GenBank. RSV infection upregulated the mRNA expression of chemokines CC and CXC and interfered with type α/β interferon-inducible gene expression by upregulation of MG11 and downregulation of G1P3.</p> <p>Conclusion</p> <p>RSV replication could induce widespread changes in gene expression including both positive and negative regulation and play a different role in the down-regulation of IFN-α and up-regulation of IFN-γ inducible gene expression, which suggests that RSV interferes with the innate antiviral response of epithelial cells by multiple mechanisms.</p

Synthesis and Properties of Red Mud-Based Nanoferrite Clinker

Red mud, an industrial waste obtained from alumina plants, is usually discharged into marine or disposed into a landfill polluting the surrounding water, atmosphere, and soil. Thus, disposal of red mud is an environmental concern and it should be recycled in an effective way. Since red mud consists of iron- and aluminum-rich phases, it can potentially be processed into cementitious material and can be used for a construction purpose. This research investigated the synthesis of nanoferrite (NF) clinker by using red mud as a raw material through chemical combustion technology for potential use in cement-based composite. Before the synthesis of NF, red mud was characterized by using XRF, XRD, and SEM techniques. From characterization results, the stoichiometric ratio of raw materials was calculated and experimentally optimized. The sample was then tested at various temperatures (815, 900, 1000, and 1100 degrees C) to find the optimum synthesis temperature. Finally, the hydraulic activity of NF was verified and the contribution to mechanical properties was determined by replacing cement with NF at various substitution levels (0, 5, 10, and 20wt%). Test results showed that the optimum condition for the synthesis of NF was found when the ratio of CaCO3/red mud was 1.5 and the sintering temperature was 815 degrees C. The synthesized NF had an average diameter of 300nm, and the main composition was brownmillerite (C(4)AF) with distinct hydraulic reaction. When NF was used as a substitute of Portland cement in mortar, the flexural strength with a 5% replacement level improved by 15%. Therefore, it can be concluded that the synthesis of NF provides an alternative approach to recycle red mud and could significantly help in reducing environmental pollution

Synthesis and Properties of Red Mud-Based Nanoferrite Clinker

Red mud, an industrial waste obtained from alumina plants, is usually discharged into marine or disposed into a landfill polluting the surrounding water, atmosphere, and soil. Thus, disposal of red mud is an environmental concern and it should be recycled in an effective way. Since red mud consists of iron- and aluminum-rich phases, it can potentially be processed into cementitious material and can be used for a construction purpose. This research investigated the synthesis of nanoferrite (NF) clinker by using red mud as a raw material through chemical combustion technology for potential use in cement-based composite. Before the synthesis of NF, red mud was characterized by using XRF, XRD, and SEM techniques. From characterization results, the stoichiometric ratio of raw materials was calculated and experimentally optimized. The sample was then tested at various temperatures (815, 900, 1000, and 1100 degrees C) to find the optimum synthesis temperature. Finally, the hydraulic activity of NF was verified and the contribution to mechanical properties was determined by replacing cement with NF at various substitution levels (0, 5, 10, and 20wt%). Test results showed that the optimum condition for the synthesis of NF was found when the ratio of CaCO3/red mud was 1.5 and the sintering temperature was 815 degrees C. The synthesized NF had an average diameter of 300nm, and the main composition was brownmillerite (C(4)AF) with distinct hydraulic reaction. When NF was used as a substitute of Portland cement in mortar, the flexural strength with a 5% replacement level improved by 15%. Therefore, it can be concluded that the synthesis of NF provides an alternative approach to recycle red mud and could significantly help in reducing environmental pollution

Graphene/silicon heterojunction for reconfigurable phase-relevant activation function in coherent optical neural networks

Optical neural networks (ONNs) herald a new era in information and communication technologies and have implemented various intelligent applications. In an ONN, the activation function (AF) is a crucial component determining the network performances and on-chip AF devices are still in development. Here, we first demonstrate on-chip reconfigurable AF devices with phase activation fulfilled by dual-functional graphene/silicon (Gra/Si) heterojunctions. With optical modulation and detection in one device, time delays are shorter, energy consumption is lower, reconfigurability is higher and the device footprint is smaller than other on-chip AF strategies. The experimental modulation voltage (power) of our Gra/Si heterojunction achieves as low as 1 V (0.5 mW), superior to many pure silicon counterparts. In the photodetection aspect, a high responsivity of over 200 mA/W is realized. Special nonlinear functions generated are fed into a complex-valued ONN to challenge handwritten letters and image recognition tasks, showing improved accuracy and potential of high-efficient, all-component-integration on-chip ONN. Our results offer new insights for on-chip ONN devices and pave the way to high-performance integrated optoelectronic computing circuits

Geographical subdivision of Alviniconcha snail populations in the Indian Ocean hydrothermal vent regions

The hairy snails of the genus Alviniconcha are representative deep-sea hydrothermal vent animals distributed across the Western Pacific and Indian Ocean. Out of six known species in the genus Alviniconcha, only one nominal species of A. marisindica was found in the Indian Ocean from the Carlsberg Ridge (CR), Central Indian Ridge (CIR) to the northern part of Southwest Indian Ridge (SWIR) and Southeast Indian Ridge (SEIR). Recently, the Alviniconcha snails were found at three new vent fields, named Onnare, Onbada, and Onnuri, in the northern CIR, which promotes a more comprehensive phylogeographic study of this species. Here, we examined the phylogeography and connectivity of the Alviniconcha snails among seven vent fields representing the CR and CIR based on DNA sequence data of a mitochondrial COI gene and two protein-coding nuclear genes. Phylogenetic inferences revealed that the Alviniconcha snails of the newly found in the northern CIR and two vent fields of Wocan and Tianxiu in the CR were divergent with the previously identified A. marisindica in the southern CIR and mitochondrial COI data supported the divergence with at least greater than 3% sequence divergence. Population structure analyses based on the three genetic markers detected a phylogeographic boundary between Onnuri and Solitaire that divides the whole snail populations into northern and southern groups with a low migration rate. The high degree of genetic disconnection around the ‘Onnuri’ boundary suggests that the Alviniconcha snails in the Indian Ocean may undergo allopatric speciation. The border may similarly act as a dispersal barrier to many other vent species co-distributed in the CIR. This study would expand understanding the speciation and connectivity of vent species in the Indian Ocean