Plasmonic Demultiplexer and Guiding

Two-dimensional plasmonic demultiplexers for surface plasmon polaritons (SPPs), which consist of concentric grooves on a gold film, are proposed and experimentally demonstrated to realize light-SPP coupling, effective dispersion and multiple-channel SPP guiding. A resolution as high as 10 nm is obtained. The leakage radiation microscopy imaging shows that the SPPs of different wavelengths are focused and routed into different SPP strip waveguides. The plasmonic demultiplexer can thus serve as a wavelength division multiplexing element for integrated plasmonic circuit and also as a plasmonic spectroscopy or filter.Comment: 17 pages, 5 figure

Power Optimization in Multi-IRS Aided Delay-Constrained IoVT Systems

With the advancement of video sensors in the Internet of Things, Internet of Video Things (IoVT) systems, capable of delivering abundant and diverse information, have been increasingly deployed for various applications. However, the extensive transmission of video data in IoVT poses challenges in terms of delay and power consumption. Intelligent reconfigurable surface (IRS), as an emerging technology, can enhance communication quality and consequently improve system performance by reconfiguring wireless propagation environments. Inspired by this, we propose a multi-IRS aided IoVT system that leverages IRS to enhance communication quality, thereby reducing power consumption while satisfying delay requirements. To fully leverage the benefits of IRS, we jointly optimize power control for IoVT devices and passive beamforming for IRS to minimize long-term total power consumption under delay constraints. To solve this problem, we first utilize Lyapunov optimization to decouple the long-term optimization problem into each time slot. Subsequently, an alternating optimization algorithm employing optimal solution-seeking and fractional programming is proposed to effectively solve the optimization problems at each time slot. Simulation results demonstrate that the proposed algorithm significantly outperforms benchmark algorithms in terms of long-term total power consumption. Moreover, a trade-off between the number of IRS elements and system performance is also proved

Histone H3 Lysine 9 Methyltransferase DIM5 Is Required for the Development and Virulence of Botrytis cinerea

Histone methylation is widely present in animals, plants and fungi, and the methylation modification of histone H3 has important biological functions. Methylation of Lys9 of histone H3 (H3K9) has been proven to regulate chromatin structure, gene silencing, transcriptional activation, plant metabolism and other processes. In this work, we investigated the functions of a H3K9 methyltransferase gene BcDIM5 in Botrytis cinerea, which contains a PreSET domain, a SET domain and a PostSET domain. Characterization of BcDIM5 knockout transformants showed that the hyphal growth rate and production of conidiophores and sclerotia were significantly reduced, while complementary transformation of BcDIM5 could restore the phenotypes to the levels of wild type. Pathogenicity assays revealed that BcDIM5 was essential for full virulence of B. cinerea. BcDIM5 knockout transformants exhibited decreased virulence, down-regulated expression of some pathogenic genes and drastically decreased H3K9 trimethylation level. However, knockout transformants of other two genes heterochromatin protein 1 (HP1) BcHP1 and DNA methyltransferase (DIM2) BcDIM2 did not exhibit significant change in the growth phenotype and virulence compared with the wild type. Our results indicate that H3K9 methyltransferase BcDIM5 is required for H3K9 trimethylation to regulate the development and virulence of B. cinerea

Effect of 26 Years of Intensively Managed Carya cathayensis

Chinese hickory (Carya cathayensis), a popular nut food tree species, is mainly distributed in southeastern China. A field study was carried out to investigate the effect of long-term intensive management on fertility of soils under a C. cathayensis forest. Results showed that after 26 years’ intensive management, the soil organic carbon (SOC) content of the A and B horizons reduced by 19% and 14%, respectively. The reduced components of SOC are mainly the alkyl C and O-alkyl C, whereas the aromatic C and carbonyl C remain unchanged. The reduction of active organic matter could result in degradation of soil fertility. The pH value of soil in the A horizon had dropped by 0.7 units on average. The concentrations of the major nutrients also showed a decreasing trend. On average the concentrations of total nitrogen (N), phosphorus (P), and potassium (K) of tested soils dropped by 21.8%, 7.6%, and 13.6%, respectively, in the A horizon. To sustain the soil fertility and C. cathayensis production, it is recommended that more organic fertilizers (manures) should be used together with chemical fertilizers. Lime should also be applied to reduce soil acidity

Symmetry-dependent electron-electron interaction in coherent tunnel junctions resolved by zero bias anomaly measurements

We provide conclusive experimental evidence that zero bias anomaly in the differential resistance of magnetic tunnel junctions (MTJs) is due to electron-electron interaction (EEI), clarifying a long standing issue. Magnon effect that caused confusion is now excluded by measuring at low temperatures down to 0.2 K and with reduced AC measurement voltages down to 0.06 mV. The normalized change of conductance is proportional to $\ln{(eV/k_{B}T)}$, consistent with the Altshuler-Aronov theory of tunneling that describes the reduction of density of states due to EEI, but inconsistent with magnetic impurity scattering. The slope of the $\ln{(eV/k_{B}T)}$ dependence is symmetry dependent: the slopes for P and AP states are different for coherent tunnel junctions with symmetry filtering, while nearly the same for those without symmetry filtering (amorphous barriers). This observation may be helpful for verifying symmetry preserved filtering in search of new coherent tunneling junctions, and for probing and separating electron Bloch states of different symmetries in other correlated systems.Comment: preprint, 22 pages, 7 figures, expanded introductio

Poet: Product-oriented Video Captioner for E-commerce

In e-commerce, a growing number of user-generated videos are used for product promotion. How to generate video descriptions that narrate the user-preferred product characteristics depicted in the video is vital for successful promoting. Traditional video captioning methods, which focus on routinely describing what exists and happens in a video, are not amenable for product-oriented video captioning. To address this problem, we propose a product-oriented video captioner framework, abbreviated as Poet. Poet firstly represents the videos as product-oriented spatial-temporal graphs. Then, based on the aspects of the video-associated product, we perform knowledge-enhanced spatial-temporal inference on those graphs for capturing the dynamic change of fine-grained product-part characteristics. The knowledge leveraging module in Poet differs from the traditional design by performing knowledge filtering and dynamic memory modeling. We show that Poet achieves consistent performance improvement over previous methods concerning generation quality, product aspects capturing, and lexical diversity. Experiments are performed on two product-oriented video captioning datasets, buyer-generated fashion video dataset (BFVD) and fan-generated fashion video dataset (FFVD), collected from Mobile Taobao. We will release the desensitized datasets to promote further investigations on both video captioning and general video analysis problems.Comment: 10 pages, 3 figures, to appear in ACM MM 2020 proceeding