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Named entity recognition is a fundamental subtask for knowledge graph construction and question-answering in the agricultural diseases and pests field. Although several works have been done, the scarcity of the Chinese annotated dataset has restricted the development of agricultural diseases and pests named entity recognition(ADP-NER). To address the issues, a large-scale corpus for the Chinese ADP-NER task named AgCNER was first annotated. It mainly contains 13 categories, 206,992 entities, and 66,553 samples with 3,909,293 characters. Compared with other datasets, AgCNER maintains the best performance in terms of the number of categories, entities, samples, and characters. Moreover, this is the first publicly available corpus for the agricultural field. In addition, the agricultural language model AgBERT is also fine-tuned and released. Finally, the comprehensive experimental results showed that BiLSTM-CRF achieved F1-score of 93.58%, which would be further improved to 94.14% using BERT. The analysis from multiple aspects has verified the rationality of AgCNER and the effectiveness of AgBERT. The annotated corpus and fine-tuned language model are publicly available at https://doi.org/XXX and https://github.com/guojson/AgCNER.git. [ABSTRACT FROM AUTHOR]

One of the thorny problems currently impeding the applications of the fluorescence imaging technique is the poor spatial resolution in deep tissue. Ultrasound-switchable fluorescence (USF) imaging is a novel imaging tool that has recently been explored to possibly surmount the above-mentioned bottleneck. Herein, a β-cyclodextrin/indocyanine green (ICG) complex-encapsulated poly(N-isopropylacrylamide) (PNIPAM) nanogel was synthesized and studied for ex vivo/in vivo deep tissue/high-resolution near infrared USF (NIR-USF) imaging. To be specific, our results revealed that the average diameter of the as-prepared nanogels was significantly decreased to ~ 32 nm from ~ 335 nm compared to the reported ICG-PNIPAM nanoparticles. Additionally, the excitation/ emission characteristics of the ICG itself in present nanogels were almost completely retained, and the resultant nanogel exhibited high physiological stability and positive biocompatibility. In particular, the signal-to-noise ratio of the USF image for the PNIPAM/ β-cyclodextrin/ICG nanogel (33.01 ± 2.42 dB) was prominently higher than that of the ICG-PNIPAM nanoparticles (18.73 ± 0.33 dB) in 1.5-cm-thick chicken breast tissues. The NIR-USF imaging in 3.5-cm-thick chicken breast tissues was achieved using this new probe. The ex vivo NIR-USF imaging of the mouse liver was also successfully obtained. Animal experiments showed that the present nanogels were able to be effectively accumulated into U87 tumor-bearing mice via enhanced permeability and retention effects, and the high-resolution NIR-USF imaging of in vivo tumor was efficiently acquired. The metabolism and in vivo biodistribution of the nanogels were evaluated. Overall, the results suggest that the current nanogel is a highly promising NIR-USF probe for deep tissue and high-resolution USF imaging. [ABSTRACT FROM AUTHOR]

It is significant to study thermal balance of diesel engine under different variable geometry turbocharger (VGT) vane openings at variable altitudes, which is helpful to assess the heat distribution, control the heat load and improve the heat efficiency of the diesel engine. A thermal balance test system was built to study the influence of the VGT vane opening angles on a regulated two-stage turbocharged (RTST) diesel engine's thermal balance performance. The experiment was conducted under full load operating conditions at different altitudes (0 m, 3500 m and 5500 m). Results indicated that the heat load of engine increased and the thermal efficiency decreased with the increase of altitudes under all operating conditions. As the VGT vane openings increased, the exhaust and maximum combustion temperature increased, while the maximum cylinder combustion pressure decreased. In particular, the maximum combustion temperature was more than 2000 K when the VGT vane openings were greater than 70% at the altitude of 5500 m, and the maximum combustion pressure exceeded 17 MPa when the opening of VGT vane was 70% at 0 m. The thermal efficiency of the engine decreased with the increase of VGT vane openings at the altitudes of 0 m and 5500 m, but the thermal efficiency increased and then decreased at the altitude of 3500 m. It was finally obtained that the best openings of VGT vane was 80%, 60% and 50% under the engine speed of 2100 r/min at 0 m, 3500 m and 5500 m, respectively. [ABSTRACT FROM AUTHOR]

Non-uniform node densities occur and intermittent links exist in highly dynamic ad hoc networks. To fit these networks, researchers usually combine delay tolerant network (DTN) routing protocols and mobile ad hoc network (MANET) routing protocols. The DTN protocol separates end-to-end links into multiple DTN links, which consist of multi-hop MANET links. Determining how to arrange DTN links and MANET links from source to end and dealing with intermittent links are performance issues, because node density ranges from sparse to dense and MANET protocols are much lighter than DTN protocols. This paper presents HMDTN, an application-network cross-layer framework, to solve the previously mentioned issues. The application layer in HMDTN supports disrupt tolerance with a large data buffer while adjusting the routing table on the basis of the connection state of links (link is disrupted or recovered), which are collected by the network layer. As a result, HMDTN increases the bandwidth utilization of intermittent links without compromising the efficiency of the MANET protocol in a reliable network. The HMDTN prototype was implemented based on Bytewalla (a Java version of DTN2) and Netfilter-based AODV. Experiments on Android devices show that unlike AODV and Epidemic, HMDTN increases the bandwidth utilization of intermittent links with a negligible increase of network overhead. In particular, HMDTN maintains the network throughput as high as regular network conditions even if the network undergoes relatively long-term (dozens of seconds or few minutes) data link disruptions. [ABSTRACT FROM AUTHOR]

Background: Phospholipase D (PLD) has been proved to be involved in regulating function of fibroblasts and might play a role in mediating organic fibrosis. Aims: To investigate the role and mechanism of PLD on dimethylnitrosamine (DMN)-induced rat liver fibrosis. Methods: Fifty-five male Wistar rats were divided into normal control group, DMN model group, N-methylethanolamine (MEA) control group, and MEA-intervention group. We observed the effects of MEA, a PLD inhibitor on the development and progression of rat liver fibrosis by comparing the physical and biochemical indexes, tissue pathology, PLD activity, and typical markers and cytokines related to fibrosis in the four groups. Results: Accompanied by the down-regulation of PLD1 expression, the MEA-intervention group had improved outcomes compared with the DMN model group in terms of spleen weight, spleen/weight index, serum and tissue biochemical indexes, tissue hydroxyproline, and tissue pathology. The MEA-intervention group had lower TIMP1, COL1A1, and higher MMPs expression level than the DMN model group. The activity of PLD and PLD1, α-SMA expression level in the MEA-intervention group was much lower than those in the DMN model group. There was no significant difference between the two groups in the expression level of TGF-β1 and MCP1. Meanwhile, there were no significant differences between normal control group and MEA control group in the parameters stated above. Conclusion: Phospholipase D1 may play an important role in the development and progression of rat liver fibrosis. Inhibition of PLD may become a new strategy to prevent or alleviate liver fibrosis. [ABSTRACT FROM AUTHOR]

The wireless data collected in mobile environments provides tremendous opportunities to build new applications in various domains such as Vehicular Ad Hoc Networks and mobile social networks. Storing the data decentralized in wireless devices brings major advantages over centralized ones. In this work, to facilitate effective access control of the wireless data in the distributed data storage, we propose a fully decentralized key management framework by utilizing a cryptography-based secret sharing method. The secret sharing method splits the keys into multiple shares and distributes them to multiple nodes. However, due to node mobility, these key shares may not be available in the neighborhood when they are needed for key reconstruction. To address this challenge, we propose the Transitive Prediction (TRAP) protocol that distributes key shares among devices that are traveling together. We develop three key distribution schemes that utilize the correlation relationship embedded among devices that are traveling together. Our key distribution schemes maximize the chance of successful key reconstruction and minimize the communication overhead. We provide theoretical analysis of the robustness and security of TRAP. Our simulation results, by using the generated data from city environment and NS-2 simulator, demonstrate the efficiency and effectiveness of our key distribution schemes. [ABSTRACT FROM AUTHOR]

Recent years have witnessed the emergence of data-centric storage that provides energy-efficient data dissemination and organization in mobile wireless environments. However, limited resources of wireless devices bring unique challenges to data access and information sharing. To address these challenges, we introduce the concept of content caching networks, in which the collected data will be stored by its contents in a distributed manner, while the data in the network is cached for a certain period of time before it is sent to a centralized storage space for backup. Furthermore, we propose a metadata-guided query evaluation approach to achieve query efficiency in content caching networks. By this approach, each cache node will maintain the metadata that summarizes the data content on itself. Queries will be evaluated first on the metadata before on the cached data. By ensuring that queries will only be evaluated on relevant nodes, the metadata-guided query evaluation approach can dramatically improve the performance of query evaluation. We design efficient algorithms to construct metadata for both numerical and categorical data types. Our theoretical and empirical results both show that our metadata-guided approach can accelerate query evaluation significantly, while achieving the memory requirements on wireless devices. [ABSTRACT FROM AUTHOR]

The solubilities of 1,2,3-trimethylbenzene, 1,2,4-trimethylbenzene and 1,3,5-trimethylbenzene in mixed solvents of t-butyl alcohol (TBA) and water at 283.15, 288.15, 293.15 and 298.15 K have been determined by spectmphotometry. The mole fractions of TBA [x(TBA)] in the mixed solvent are0.000, 0.010, 0.020, 0.030, 0.040, 0.045, 0.050, 0.060, 0.080 and 0.1000. The Gibbs energies of hydrophobic interaction (HI) for the aggregating process of three methane molecules with one benene molecule in the mixed solvent are studied, and the effect of solvent structure and solute aggregating state on the strength of HI is discussed. [ABSTRACT FROM AUTHOR]

The solubilitices of benzene, toluene and diphenyl in mixed solvents of t-butyl alcohol (TBA) and water at 283.15, 288.15, 293.15 and 298.15 K have been determined by spectrophotometry. The mole fraction of TBA [ x (TBA)] in the mixed solvent are 0.000, 0.010, 0.020, 0.030, 0.040, 0.045, 0.050, 0.060, 0.080 and 0.100, respectively. The standard Gibbs energies of solution of benzene, toluene and diphenyl in the mixed solvent have also been calculated based on the solubility data. The hydrophobic interactions (HI) for the pairs of benzene-benzene, methane-benzene and methane-methane in the mixed solvent were calculated and discussed. [ABSTRACT FROM AUTHOR]

A molecularly imprinted polymer photoelectrochemical (MIP-PEC) sensor based on bismuth sulfide (Bi2S3) is described for the determination of the plasticizer dioctyl phthalate (DOP). Bi2S3 was used as the photoelectrical converter of the sensor, and visible light was utilized as the excitation source. The molecular imprinting film was prepared through the electropolymerization of monomers in the presence of DOP. Under optimal experimental conditions, the photoelectrochemical response was linearly proportional to the logarithm of the DOP concentration in the 0.5–70 pM DOP concentration range, and the detection limit was 0.1 pM. The method is highly stable and reproducible. It was applied to the determination of DOP in spiked water samples. [ABSTRACT FROM AUTHOR]