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According to optical diffraction limit, the photoresponsity of nanowire (NW)-based photodetector exponentially decreases when its NW diameter reduces to the range of deep subwavelength. In this paper, we demonstrate a photoresponse-enhanced method of the deep-subwavelength GaAs NW photodetector by using a plasmon-driven dipole antenna. Considering that the enhancement is extremely influenced by the shape and size of antenna, the structure of antenna is optimized by finite difference time domain (FDTD) solutions. The optimal structure of antenna optimizes the responsivity-enhanced factors to 1123.3 and 224.7 in NW photodetectors with NW diameters of 20 nm and 60 nm, respectively. This photoresponse-enhanced method is promising for easy-integration high-performance nanoscale photodetectors.

The formation of public opinions is a complex phenomenon that revolves around the aggregation of individuals’ beliefs. To accurately capture this phenomenon, one needs to build links from individualistic experiences to personal beliefs, which evolve in a social space through information exchange and belief revision. Despite many efforts to model opinion dynamics, the role of personal experiences and beliefs has often been overlooked. In this paper, we address this issue and propose an agent-based model in a social network. We explicitly model belief acquisition as a learning process from experiences that take the form of local data sets. Agents interact through a social network and update their beliefs based on how accurately the belief reflects experiences. Through iterations of interactions, the agents are able to arrive at a unified belief. We then focus on the accuracy of the personal beliefs during their evolution and the impact of the social network structure. On a micro-level, we investigate positional attributes such as the centrality of nodes that affect belief accuracy. On a macro-level, we investigate structural features that affect the overall performance. We then investigate a method to intervene in opinion formation through expert agents. Experiments are performed on real-world and synthetic data sets, which validate a number of important structural insights.

Objectives: In this paper, we explore the effects of breathing meditation training on the sustained attention level, mindfulness attention awareness level, and mental state of nurses in the operating room. Methods: We enrolled 40 nurses from September 2019 to December 2019, and divided them into a control group (N=20) and an observation group (N=20) using a random number table. The control group received routine training, based on which the observation group received breathing meditation training. We compared their sustained attention index, fatigue score, mindfulness attention awareness score, mental state score, work stress score, career satisfaction score, and career happiness index. Results: After training, the sustained attention response time was shorter at 8:00 and 18:00 in the observation group than in the control group (p < .05). The physical fatigue score, mental fatigue score, reduced activity score, reduced motivation score, and overall fatigue score of the observation group were lower than those of the control group (p < .05). The observation group had a higher mindfulness attention awareness score than did the control group (p < .05). The SAS and SDS scores of the observation group were lower than those of the control group (p < .05). The work stress score of the observation group was lower than that of the control group, whereas the career satisfaction score and career happiness index were higher (p < .05). Conclusion: Breathing meditation training can improve the sustained attention level and mindfulness attention awareness level, reduce the feeling of fatigue and work stress, help adjust the mental state, and enhance the career satisfaction and career happiness of nurses in the operating room.

The design process of large-scale integrated circuits is complex and time-consuming. The introduction of VLSICAD tools saves a lot of time, manpower and material resources, which is of great significance to the development of integrated circuit technology. Aiming at the difference of area and long side length of each module in VLSI layout planning, the concept of weight is put forward, and according to the difference of weight of each module; In the optimization process, the corresponding modules are selected with different probabilities, and the porous ultra-low K dielectric is simulated by using the self-similar fractal model, and its dielectric constant is analyzed. By comparing with the experimental data, we find that the experimental data are in good agreement with the results obtained according to the theory. This also proves the validity of the model.

The transmission characters of a narrow slit were an interesting topic for a long time. In this paper, the transmission characters of an air slit carved form a metal film was discussed rigorously. The narrow slit was treated to be a three-layer-waveguide with two complex refractive index claddings. The transmission character eigen equations were derived by solving analytically from Maxwells equations and by matching the boundary conditions at the interfaces. The electromagnetic fields in both sides of the claddings and inside of the air slit were obtained. For a given example, numerical simulations were presented. The field distribution and the longitude phase constants at different wavelengths and with different width of the slits were calculated. Five modes were supported, and one surface Plasmon mode was attributed and four guided modes were attributed from their transmission characters. The p-polarized surface Plasmon mode might play an important role in the extraordinary optical transmission of light through arrayed subwavelength holes.

Nitrogen cycling in soil, which associated with microbes, plays an important role in plant growth. Irrational application of nitrogen fertilizer could disrupt the structure of soil microbial community, thus inhibiting the uptake of nitrogen by plants and increasing nitrogen leaching in soil. Field and pot leaching experiments with the combined application of chitin fertilizer and selenium (Se) were carried out in order to develop an approach to improve the efficiency of nitrogen fertilizer utilization and reduce runoff by nitrogen loss in orchards of Guanxi pomelo in Fujian Province. Our results showed that application of chitin fertilizer combined with Se to the soil with reduced nitrogen and phosphate fertilizer (nitrogen fertilizer decreased by 25% and phosphate fertilizer decreased by 50%) could significantly increase the fruit yield, vitamin C and solid-acid ratio in the fruit. The application of chitin fertilizer and Se can not only lead to the increase of total nitrogen content in plant leaves but also the alkali-hydrolyzable nitrogen content in soil which enhancing soil nitrogen supplying capacity. It has been found that the adding the chitin fertilizer and Se into soil can significantly affect the structure and functional categories microbial communities and its activities. This is directly evidenced by the findings that the expression level of several groups of N metabolism and transporting related genes (i.e. amoAB and nxrA in nitrification, narG, nirK, norBC, and nosZ in denitrification, nirD, narH in dissimilatory nitrogen reduction, and ureC in ammoniation) has been drastically up-regulated. Our results indicate this strategy for reducing N and P input while maintaining and improving plant performance by supplementing with micronutrient Se and chitin fertilizer can increase the fruit yield and improve the quality of Guanxi pomelo through improving fertilizer use efficiency.

Huanglongbing (HLB) caused by 'Ca. Liberibacter. Asiaticus (Clas)' is one of the destructive diseases for citrus, threatening the development of citrus industry. Adopting a proper fertilization method instead of using pesticides seems particularly important, which would contribute to a sustainable development of orchard. In this study, the impact of soil application of nutrients combined with foliar spray of macro- and micro-nutrients on the incidence of HLB and the phyllosphere and rhizosphere bacterial microbiome was investigated in Gannan Navel Orange orchard from 2015 to 2018. Compared with the control (T1), the yield of Gannan Navel Orange in all other treatments applied with macro- and micro-nutrients increased significantly in 2018 (by 20.5%-45.8%), but not in the first two years (2016-17). Among treatments, Ca + Mg + B application in soil (T2) showed the highest yield and lowest HLB incidence. According to the PCR results, CLas was negative in T2 but positive in the control, which directly proved HLB incidence was reduced with Ca + Mg + B application in soil. Moreover, 16S rRNA sequencing was used to characterize rhizosphere and phyllosphere microbial communities. Results showed that microbial biodiversity was increased and microbial community structure was altered in T2 treatment, of which the beneficial bacteria were enriched in phyllosphere and rhizosphere. The results of PICRUSt showed that in T2 treatment, rhizosphere microbe contained more membrane transport (ABC transporters) genes, while, carbohydrate metabolism genes were enriched in the control rhizosphere due to HLB obstruct the photosynthetic metabolite transport. In summary, results indicated that macro- and micro-nutrients application improved the yield of Gannan Navel Orange and soil application of Ca + Mg + B reduced HLB incidence by altering microbial community structure and increasing microbial biodiversity. This study developed an environment-friendly way to reduce HLB incidence and improve the yield of citrus.

Xyloglucan endotransglycosylase/hydrolase (XTH) belongs to the GH16 subfamily of the glycoside hydrolases of carbohydrate active enzymes and plays an important role in the structure and function of plant cell walls. In this study, 11 members of the XTH gene family were cloned from Populus tomentosa. A bioinformatics analysis revealed that 11 PtoXTHs could be classified into three groups, where PtoXTH27 and PtoXTH34 were most likely to exhibit XTH activity. Biochemical analyses of purified PtoXTHs demonstrated that PtoXTH27 and PtoXTH34 had detectable xyloglucan endotransglucosylase (XET) activity, while the others did not exhibit XET or XEH activity. Moreover, enzymatic assays revealed that the optimum reaction temperature of both PtoXTH27 and PtoXTH34 was 37 °C, while their optimum pH values differed, such that PtoXTH27 was 6.0 and PtoXTH34 was 5.0. Enzyme kinetic parameters indicated that PtoXTH34 had higher affinity for the receptor substrate, XXXG, implying that PtoXTH34 and PtoXTH27 in plants have different substrate structure specificity. Finally, heterologous expression of XTH significantly increased intracellular total sugar content and osmotolerance of yeast cells, indicating that PtoXTH27 and PtoXTH34 are potentially involved in osmotic stress responses. These results clearly demonstrate the enzymatic characteristics and putative role of XTH in osmotic stress responses.

Ensemble learning aims to train and combine multiple base learners in the hope of improving the overall performance. Existing ensemble algorithms rely on a centralized framework where each base learner has access to the entire training dataset. We combine the technology of blockchains which is mainly used for data validation with ensemble learning and propose a decentralized framework where data are distributed among multiple base learners, who exchange their respective data to improve the collective predictive abilities. We develop two realizations of this framework, based on static and dynamic decision trees, respectively. We evaluate our methods over 20 real-world datasets and compare them against other centralized ensemble methods. Experimental results show that the proposed method obtains improved accuracy scores through sample exchange and achieves competitive performance with state-of-the-art ensemble methods whereas the base learners store only a small fraction of the samples.

An intelligent water regime detection system was designed for water detection. In the designed system, water level is detected by a pressure sensor and water pH is detected by a pH meter. After being processed by the AD chip TLC2543, the data are sent to the MCU via serial communication and the detection result is displayed on OLED screen or Bluetooth mobile phone. The software adopts time-sharing and power-down operation modes, and combines the relay to turn on/off the MCU peripheral circuit to reduce power consumption. The measurement deviations of water level, pH, and voltage were respectively less than 2 mm, 0.1, and 0.01 V and the minimum operating current was less than 6 mA. The low-power, high-precision and intelligent water regime detection is realized by the designed system.

Sclerotinia stem rot (SSR), caused by Sclerotinia sclerotiorum (S. sclerotiorum), one of the most destructive diseases in many crops including Brassica napus L. The extensive use of fungicides to control S. sclerotiorum caused severe damage to the environment in the long term. Increasing study reported that selenium (Se) is a beneficial element for plant by promoting growth and enhancing disease resistance. In this study, it was found that Se in soil shortened lesion length by 19.14% on rape stem infected with S. sclerotiorum. While resistance mechanism of rape stem against S. sclerotiorum remains unknown. Transcriptomic analysis of rape stem was performed and the results indicated that genes related to antifungal pathways were up-regulated. Moreover, metabonomic analysis was carried out to study the inhibitive effect of the dissolved organic matter derived from rape straw with Se pretreatment in soil (RSDOMSe) on S. sclerotiorum mycelium, results showed that RSDOMSe caused severe damage to energy metabolism of mycelium. Further study indicated that RSDOMSe decreased the pathogenicity of mycelium on rape leaves significantly, and enhanced content of chlorophyII, carotenoids, OD phenol and activities of phenylalanine ammonia-lyase (PAL), polyphenol oxidase (PPO) in rape leaves, which suggested that RSDOMSe plays a positive role in regulating oxidative stress responses of plant when infected with S. sclerotiorum. In addition, when compared with dimcthachlon (DIM) treatment alone, DIM combined with RSDOMSe resulted in higher inhibition on mycelial growth of S. sclerotiorum (the inhibition ratio of nearly 60%). Results in this study suggested that Se enhanced the resistance of rape stem against S. sclerotiorum because of the up-regulated genes related to antifungal pathways, and RSDOMSe improved the mycelial growth inhibition and decreased the pathogenicity of mycelium on rape leaves. Overall, Se as well as Se-enrich byproducts, possessed great potential to be developed as ecological fungicides for controlling S. sclerotiorum.

We demonstrate a subwavelength GaAs nanowire photodetector with a half-wave Hertz dipole antenna. An enhancement by a factor of 100 in the responsivity is obtained due to the antenna resonance.

In an increasingly interconnected and distributed world, the ability to ensure communications becomes pivotal in day-to-day operations. Given a network whose edges are prone to failures and disruptions, reliability captures the probability that traffic will reach a target location by traversing edges starting from a given source. This paper investigates reliability in decentralized and complex networks. To evaluate reliability, we introduce a multi-agent method that involves pathfinding agents to reduce the graph. Performance of this method is tested on scale-free and small-world networks as well as real-world spatial networks. We also investigate reliability score which aims to rank the capability of nodes in terms of traffic dissemination traffic across all nodes. Analysis over spatial networks indicates that the reliability score correlates with central and sub-central regions in a geographical region.

A general game playing (GGP) system aims to play previously unknown board games with changeable rules without human intervention. Taking changeable game rules into consideration, a game description language presents formal descriptions of a game. Based on this description, legal moves can be automatically generated so that each player in GGP system only needs to solve the problems of searching and learning for playing well. Traditional search methods demand the player to compute all legal moves, which can be very time consuming. In GGP, the coordinate of cells in the game board is very important in board game rules. Thus we address the relationship among cell coordinates. Borrowing an idea from rule learning to prune the board game search tree, we propose a new search optimization method to reduce running time when searching a large search space. We further prove that this method can effectively improve the searching efficiency through a comparative experiment with Gomoku game in GGP system.

Sclerotinia sclerotiorum (S. sclerotiorum) is a devastating fungal pathogen with worldwide distribution, and threatened the agro-ecological safety in the long term. To control the damage caused by Sclerotinia diseases, as well as consider the fungicide resistance and chemical residues, strategy of which plant nutritional regulation, as an eco-friendly approach, is gaining much significance. Selenium (Se), as a beneficial microelement for plant, has been manifested to be effective in inhibiting the mycelial growth of S.sclerotiorum in our previous study. In the present study, we observed that Se (both selenate and selenite) inhibited the formation of sclerotia, which is an important life form in the disease cycle of S. sclerotiorum. And the inhibition ratios of number of sclerotia in treatments of Se(VI)5.0 and Se(IV)5.0 were 54.55% and 43.84%, respectively; the inhibition ratios of weight of sclerotia in treatments of Se(VI)5.0 and Se(IV)5.0 were 42.29% and 25.67%, respectively. Results suggested that Se inhibited mycelial growth, severely damaged sclerotial ultrastructure, reduced the capacity of acid production, decreased superoxide dismutase (SOD) and catalase (CAT) activities, increased the content of hydrogen peroxide (H2O2) and superoxide anion (O2-) in mycelium, and all of these resulted in the reduction in sclerotial formation. Further studies revealed that Se application in medium increased Se concentration in sclerotia and thus inhibited sclerotial germination. Moreover, the pathogenicity of mycelia germinating from sclerotia that pretreated with Se, decreased significantly to rape leaves. These findings broadened our understanding of Se application in plant protection, as well as provided evidences for developing environment-friendly fungicide for S. sclerotiorum control.

A self-similarity model applying the Sierpinski carpet approximation for the effective dielectric constant of nanoporous low-k dielectrics is proposed based on the statistically self-similar characteristics of pore size distributions in the medium and on the 'mixture rule' technique. The proposed model for the dielectric constant is expressed as a function of porosity (related to stage n of Sierpinski carpet) and the dielectric coefficient of components of the medium. The model predictions are compared with the existing experimental data and with other model predictions, and good agreement is obtained between the present model predictions and the experimental data. The proposed technique may have the potential of analysing other properties such as thermal conductivity and Young's modulus.