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We propose a cascaded neural network (NN) to simultaneously identify the modulation formats and monitor the optical-signal-to-noise ratio (OSNR). In the second-level network, it is a single deep NN (DNN) rather than multiple sub-networks, which makes the architecture more compact and can save the resource for real implementation. However, since the data set is constituted from all modulation formats, the universality can be guaranteed but not for the accuracy and the complexity. To accelerate the estimation process and improve the accuracy, we introduce the transfer learning (TL) and reconstruct the data set with a part from all of the modulation formats for universality and another part from a specific modulation format for TL to pursue higher accuracy. In the experiment, we compare the proposed cascaded single neural network (CSNN) with or without TL, cascaded multiple neural networks (CMNN) and adaptive multi-task learning (MTL) for MFI and OSNR monitoring. In the first-level NN, all of the three schemes can achieve the accuracy of MFI as 100%. In the second-level NN, the CSNN with TL (TL-CSNN) can significantly improve the training speed and decline the RMSE of 0.19 dB compared with CSNN without TL. The TL-CSNN also has faster convergence speed and is more stable compared with CMNN and adaptive MTL.

Radish (Raphanus sativus L.), an important root vegetable crop of the Brassicaceae family, has a high level of anthocyanin accumulation in its pigment root tissues. It was reported that MYB transcription factors (TFs) play vital roles in plant development and anthocyanin metabolism, and the PAP1/2 could promote expression of anthocyanin biosynthesis genes. In this study, a total of 187 radish MYB genes (RsMYBs) were identified in the radish genome and clustered into 32 subfamilies. Among them, 159 RsMYBs were localized on nine radish chromosomes. Interestingly, 14 RsMYBs exhibited differential expression profiles in different taproot developmental stages among four differently colored radish lines. A number of RsMYBs were highly expressed in the pigmented root tissues at the maturity stage, several genes including RsMYB41, RsMYB117, and RsMYB132 being homologous to PAP1/2, showed high expression levels in the red skin of NAU-YH (red skin-white flesh) taproot, while RsMYB65 and RsMYB159 were highly expressed in the purple root skin of NAU-YZH (purple skin-red flesh), indicating that these RsMYBs might positively regulate the process of anthocyanin accumulation in radish taproot. These results would provide valuable information for further functional characterization of RsMYBs, and facilitate clarifying the molecular mechanism underlying anthocyanin biosynthesis in radish.

In this work, by performing state-of-the-art first-principles methods combined with molecular dynamic (MD) simulation, we theoretically investigate the electronic and mechanical behaviours of small-angle twisted bilayer black phosphorus (tbBP) under uniaxial tensile deformation. Twistronics, namely the regulation of electronic properties by Moiré physics, is demonstrated as the gene - the most crucial factor dominating not only electronic behaviour but also mechanical behaviour of tensile deformed tbBP. Compared to untwisted few-layer black phosphorus (utBP) with strong electronic sensitivity to geometric deformation, the existence of Moiré patterns in tbBP leads to spatial electronic localization, giving rise to the conservation of direct band gaps and stability of phonon limited carrier mobility under tensile deformation along the armchair direction. Moreover, during the fracture failure process, the nucleation of micro-cracks is preferentially detected at the transitional pattern boundary areas in tbBP, which could be attributed to the intra-layer maldistribution of mechanical strengths in Moiré superlattices. The explorations of twistronics in tensile strained bilayer black phosphorus contribute to the better understanding of such Moiré superlattice structures and provide insights for the design of new 2D van der Waals heterostructures in flexible nano-electronic devices.

Purpose The purpose of this paper is to study where to place industrial solid waste treatment centers among the 16 prefecture-level cities under its jurisdiction. Design/methodology/approach This paper adopts the cross-efficiency data envelopment analysis (DEA) model, with the industrial land price and average annual salary per capita as inputs, while coverage, total transportation distance, number of industrial enterprises and total amount of industrial solid waste are used as outputs. Findings Based on the spatial efficiency scores calculated by using the new presented models, the authors find that the most efficient construction site are Chizhou, Chuzhou, Suzhou and Bengbu. That is quite different from the results obtained by using traditional approach. Originality/value This paper evaluates the spatial efficiency by using combinations of the four locations as the decision-making units of the DEA model, which could be used as an objective way to allocate limited resource. In addition to the resource allocation of the industrial solid waste treatment center, the method in this paper can also be applied to other spatial aspects of resource allocation.

We present here three chromophores with the same tricyanofuran acceptor, but with different donor moieties and bridges, synthesized by the conventional technique. Compared with chromophore without the substituted group, these modified chromophores show better stability. Structure analysis and photophysical properties were carried out to compare the molecular mobility and steric hindrance effect on chromophores. Density functional theory (DFT)was used to calculate the hyperpolarizability (β), and the results showed that the high molecular hyperpolarizability of these chromophores can be effectively translated into large electro-optic coefficients. By doping these chromophores with a high loading of 25 wt% in amorphous polycarbonate (APC), electro-optic (EO) coefficients (r33) of up to 163 pm V−1 at 1310 nm can be achieved. These results indicated that the introduced alkoxy group on the donor part or bridge part can enhance the donor ability and can also reduce intermolecular electrostatic interactions, thus enhancing the macroscopic electro-optic activity, which indicated that the structure–property relationship was essential.

The CPA (cation proton antiporter) family plays an essential role during plant stress tolerance by regulating ionic and pH homeostasis of the cell. Radish fleshy roots are susceptible to abiotic stress during growth and development, especially salt stress. To date, CPA family genes have not yet been identified in radish and the biological functions remain unclear. In this study, 60 CPA candidate genes in radish were identified on the whole genome level, which were divided into three subfamilies including the Na+/H+ exchanger (NHX), K+ efflux antiporter (KEA), and cation/H+ exchanger (CHX) families. In total, 58 of the 60 RsCPA genes were localized to the nine chromosomes. RNA-seq. data showed that 60 RsCPA genes had various expression levels in the leaves, roots, cortex, cambium, and xylem at different development stages, as well as under different abiotic stresses. RT&ndash, qPCR analysis indicated that all nine RsNHXs genes showed up regulated trends after 250 mM NaCl exposure at 3, 6, 12, and 24h. The RsCPA31 (RsNHX1) gene, which might be the most important members of the RsNHX subfamily, exhibited obvious increased expression levels during 24h salt stress treatment. Heterologous over-and inhibited-expression of RsNHX1 in Arabidopsis showed that RsNHX1 had a positive function in salt tolerance. Furthermore, a turnip yellow mosaic virus (TYMV)-induced gene silence (VIGS) system was firstly used to functionally characterize the candidate gene in radish, which showed that plant with the silence of endogenous RsNHX1 was more susceptible to the salt stress. According to our results we provide insights into the complexity of the RsCPA gene family and a valuable resource to explore the potential functions of RsCPA genes in radish.

A series of novel chromophores based on same bis (N,N-diethyl) aniline donor have been synthesized and systematically characterized. Chromophores with rigid steric hindrance groups showed superb thermal stabilities with high thermal decomposition temperatures above 260 °C. Besides, compared with the chromophore (y2) without isolation group, these new chromophores show better intramolecular charge-transfer absorption. Most importantly, the introduction of rigid steric hindrance groups can effectively reduce dipole–dipole interactions to translate their relatively β values into bulk large electro-optic activities. The electro-optic coefficient of poled films containing 25 wt % of these new chromophores doped in amorphous polycarbonate afforded values of 163, 129, 183 and 196 pm V−1 at 1310 nm for chromophores y1-y4 respectively. These results indicated that introducing rigid isolation group to control the shape of chromophores can efficiently reduce intermolecular electrostatic interactions, thus enhancing the macroscopic electro-optic activity. These properties, together with good solubility, suggest the potential use of these chromophores as advanced material devices.

With the aim to effectively improve the interface between ZrO2 toughened Al2O3 (ZTA) particles and metal matrix, nickel was deposited on the surface of ZTA particles by electroless plating method. Formation mechanism of nickel coating and effects of the solution pH, loading capacity of ZTA particles and temperature on the nickel deposition were investigated. Microstructures, thickness and element distributions of nickel coating were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The results showed that the nickel was successfully deposited on the surface of ZTA particles by electroless plating without noticeable defects. The process of electroless nickel plating could be explained by combination of atomic hydrogen and electrochemistry theories. The interfacial nucleation of nickel is easier to form than spontaneous nucleation in the solution. Deposited Nickel has priority on the surface of ZTA particles comparing to that in solution. The optimal conditions to coat nickel on the surface of ZTA particles are: solution pH 4.7–4.8, loading capacity 15–20 g/L, and electroless plating temperature 85 °C. The ZTA particle reinforced iron matrix composites prepared by powder metallurgy could have better interfacial bonding between ZTA particle and iron matrix because of the nickel coating on the surface of ZTA particle. Nickel diffuses into the iron matrix during the sintering preparation of composite materials. The interface between ZTA particle and iron matrix presents the evidence of non-chemical bonding.

We propose a novel cascaded neural network with abnormality monitoring to simultaneously identify the modulation format and monitor the OSNR. The experimental results show 97.5 % MFI accuracy and 0.167dB average MAE for OSNR monitoring.

In recent years, with the rapid development of China’s logistics industry and urban service industry, electric bicycles have gradually become an important means of transportation in cities due to their flexibility, green technology, and low operating costs. Because electric bicycles travel though motor vehicle lanes and nonmotor vehicle lanes, the conflict between motor and nonmotor vehicles has become increasingly prominent, and the safety situation is not optimistic. However, most theories and models of mixed traffic flow are based on motor vehicles and bicycles and few involve electric bicycles. To explore the traffic safety situation in an urban mixed traffic environment, this paper first uses cellular automata (CA) to establish a three-strand mixed traffic flow model of motor vehicles, electric bicycles, and bicycles and verifies the reliability of the model by using a MATLAB simulation based on the actual survey data. Then, using the technology of traffic conflicts and the conflict rate as the index to evaluate the traffic safety situation, the change in the conflict rate with different road occupancies and different proportional coefficients of motor vehicles is studied. In the end, the conflict rate is compared between the mixed traffic flow and the setting of a physical isolation divider, which provides some suggestions on when to set a physical isolation divider to separate motor vehicles from nonmotor vehicles. The results show that in a mixed traffic environment, the conflict rate first increases and then decreases with increasing road occupancy and reaches a peak when the road occupancy is 0.6. In addition, in mixed traffic environments, the conflict rate increases with an increasing proportional coefficient of the motor vehicle. When the road occupancy rate is within the range of [0.6, 0.9] or when the proportional coefficient of motor vehicle is between [0.8, 0.9], a physical isolation divider can be set to separate motor vehicles and nonmotor vehicles from the space to improve traffic safety.

Hydrazinolyzed cellulose-graft-polymethyl acrylate (Cell-g-PMA-HZ), an efficient adsorbent for removal of Cd(II) and Pb(II) from aqueous solution, has been prepared by ceric salt-initiated graft polymerization of methyl acrylate from microcrystalline cellulose surface and subsequent hydrazinolysis. The influences of initial pH, contact time, and temperature on adsorption capacity of Cell-g-PMA-HZ as well as adsorption equilibrium, kinetic and thermodynamic properties were examined in detail. As for Cd(II) adsorption, kinetic adsorption can be explained by pseudo-second-order, while adsorption isotherm fits well with Langmuir isotherm model, from which maximum equilibrium adsorption capacity can be derived as 235.85 mg g−1 at 28 °C. Further thermodynamic investigation indicated that adsorption of Cd(II) by adsorbent Cell-g-PMA-HZ is endothermic and spontaneous under studied conditions. On the other hand, isotherm of Pb(II) adsorption fits well with Freundlich isotherm model and is more likely to be a physical-adsorption-dominated process. Consecutive adsorption–desorption experiments showed that Cell-g-PMA-HZ is reusable with satisfactory adsorption capacity.

Calcium-activated chloride channels (CaCCs) as a kind of widely expressed ion channels play crucial roles in a variety of physiological regulation. TMEM16A has been identified as the molecular basis of CaCCs in numerous cell types and is considered a new drug target for many diseases. Regulating the function of TMEM16A through small molecule modulators has become a new strategy to improve respiratory and digestive dysfunction and even tumor therapy. Herein, we obtained 5 sesquiterpenoids, named curzerenone, curdione, furanodienone, curcumol and germacrone with TMEM16A inhibition and revealed their mechanism of action by fluorescent and electrophysiological assays. Cell-based YFP fluorescence data demonstrated that 5 compounds inhibited TMEM16A-mediated I- influx in a dose-dependent manner. To explore the mechanism of 5 compounds on CaCCs, FRT cells with high expression of TMEM16A, HBE, HT-29 and T84 cells and mouse colons were used in short-circuit current assay. Our results showed that 5 compounds inhibited the Ca2+-activated Cl- currents generated by the Eact, ATP and UTP stimulation, and this inhibitory effect was related not only to the direct inhibition of channel opening, but also the inhibition of intracellular Ca2+ concentration and K+ channel activity. In addition to CaCCs, these 5 compounds also had definite inhibitory activities against cystic fibrosis transmembrane regulator (CFTR) at the cellular level. In summary, these compounds have the potential to regulate the activites of TMEM16A/CaCCs and CFTR channels in vitro, providing a new class of lead compounds for the development of drugs for diseases related to chloride channel dysfunction.

Aerobic photosynthetic organisms such as algae produce reactive oxygen species (ROS) as by-products of metabolism. ROS damage biomolecules such as proteins and lipids in cells, but also act as signaling molecules. The mechanisms that maintain the metabolic balance in aerobic photosynthetic organisms and how the cells specifically respond to different levels of ROS are unclear. Glutathione peroxidase (GPX) enzymes detoxify hydrogen peroxide or organic hydroperoxides, and thus are important components of the antioxidant system. In this study, we employed a Chlamydomonas reinhardtii glutathione peroxidase knockout (gpx5) mutant to identify the genetic response to singlet oxygen (1O2) generated by the photosensitizer rose bengal (RB). To this end, we compared the transcriptomes of the parental strain CC4348 and the gpx5 mutant sampled before, and 1 h after, the addition of RB. Functional annotation of differentially expressed genes showed that genes encoding proteins related to ROS detoxification, stress-response-related molecular chaperones, and ubiquitin&ndash, proteasome pathway genes were upregulated in CC4338. When GPX5 was mutated, higher oxidative stress specifically induced the TCA cycle and enhanced mitochondrial electron transport. Transcription of selenoproteins and flagellar-associated proteins was depressed in CC4348 and the gpx5 mutant. In addition, we found iron homeostasis played an important role in maintaining redox homeostasis, and we uncovered the relationship between 1O2 stress and iron assimilation, as well as selenoproteins. Based on the observed expression profiles in response to different levels of oxidative stress, we propose a model for dose-dependent responses to different ROS levels in Chlamydomonas.

Moir\'e patterns on two-dimensional van der Waals heterostructure can give rise to unique electronic and transport properties. In this work we report a theoretical investigation of Moir\'e patterns on twisted bilayer black phosphorus (tbBP). It is found that the Moir\'e pattern has extraordinary effects and leads to significant asymmetry with respect to transport direction and carrier type. The high-symmetry local stacking configurations in the Moir\'e pattern act as impurities with sizes at the Moir\'e length scale, and these ``Moir\'e impurities'' induce flatbands and localized states in tbBPs. Because both the conduction band minimum and valence band maximum are dominated by these localized states, the deformation potential limited carrier mobility is significantly affected: the electron mobility of tbBPs reduces by almost 20-fold when twisting from zero angle $(\ensuremath{\sim}2560\phantom{\rule{0.222222em}{0ex}}\phantom{\rule{4pt}{0ex}}{\mathrm{cm}}^{2}\phantom{\rule{0.16em}{0ex}}{\mathrm{V}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}{\mathrm{s}}^{\ensuremath{-}1})$ to just $1.{8}^{\ensuremath{\circ}}$ $(\ensuremath{\sim}131\phantom{\rule{0.28em}{0ex}}{\mathrm{cm}}^{2}\phantom{\rule{0.16em}{0ex}}{\mathrm{V}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}{\mathrm{s}}^{\ensuremath{-}1})$. The microscopic physics behind these effects are revealed by the real-space wave functions.

A novel broadband light source based on supercontinuum (SC) generation seeded by random distributed feedback fiber laser (RFL) is proposed and demonstrated for the first time. A half-opened fiber cavity formed by FBG and TrueWave fiber is used to generate random lasing and SC simultaneously. Experimental results indicate that RFL can be used as an effective pump for generation of SC. SC with 20-dB bandwidth of >250 nm was obtained. Such a broadband SC light source seeded by RFL may pave a way to generate high power broadband RFLs for use in optical sensing and measurement.

Organic dyes have received extensive attention due to their broad applications related to nonlinear optics, biological and chemical sensors. Herein, a novel chromophore based on double donors and tricyanofuran acceptor was prepared and studied. This new chromophore displayed excellent thermal stability showing the onset decomposition temperature higher than 230 °C. Moreover, density functional theory calculation shows that chromophore y1 presented a lower HOMO-LUMO energy gap and a much larger hyperpolarizability (β) than the single donor chromophore. These results showed that the double donors can increase the donor ability and thus enhance nonlinear optical properties.

Broadly-tunable pulse generation in cavity-free graphene random lasers is reported, with tunable pulsewidths across two orders-of-magnitude to less-than 900 ps, tunable repetition over three orders-of-magnitude up to 3 MHz, and 41-dB singly-polarized extinction ratio.