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To explore the performance of improved watershed algorithm in processing magnetic resonance imaging (MRI) images and the effect of the processed images on the treatment of lumbar brucellar spondylitis (BS) with abscess by the posterior approach, the watershed algorithm was improved by adding constraints such as noise reduction and regional area attribute. 50 patients with abscessed lumbar disc herniation admitted to the hospital from January 2018 to January 2019 were selected, and all of them were examined by MRI. They were rolled into two groups in random. The treatment group (n = 25) accepted surgery with the aid of MRI images processed by the improved watershed algorithm, and the control group (Ctrl group) (n = 25) accepted surgery with the aid of unprocessed MRI images. The improved watershed algorithm can accurately segment the spine, and the segmentation results were relatively excellent. In contrast with the unprocessed MRI image, that processed by the improved watershed algorithm had a positive effect on the operation. In contrast with the Ctrl group, the visual analogue scale pain score (VAS), oxygen desaturation index (ODI), erythrocyte sedimentation rate (ESR), and high sensitivity C-reactive protein (CRP) were obviously lower ( p < 0.05 ). The improved watershed algorithm proposed performs better in MRI image processing and can effectively enhance the resolution of MRI images. At the same time, the posterior approach has a good effect in the treatment of lumbar BS with abscess and is worthy of clinical promotion.

Nowadays, various pipelines are broadly used in the transportation of resources in the production process and life applications, such as natural gas, compressed air, water, oil and so on. Pipe leakages usually occur due to the improper manufacturing process, installation of valves or other devices, prolonged use, etc. Pipeline leakage will cause energy loss, pollution and other severe problems, which will lead to equipment damage and even casualties. Therefore, the detection of pipeline leakage is significantly important. Traditional pipeline leak detection requires visual inspection or many fixed detection sensors. This may cause missed inspection by human errors and also will greatly increase the cost on the expensive devices. Compared with visual inspection and specific testing devices, mobile robots have the advantages of portability, economic cost and wide application for effective and efficient pipeline leakage detection. Robots can be deployed on lines or near equipment prone to pipeline leaks which can be detected online according to the path set. This paper presents an effective pipeline leak detection method to monitor the leakage of a two-stage reciprocating compressor with a mobile robot. An android mobile phone is installed on the mobile robot platform. After the robot moves to the monitoring point, the microphone of the mobile phone starts to collect environmental sound. The cross-correlation analysis is then performed on the LABVIEW software platform to implement online detection of different leakage faults. The experimental results show that the extreme value of the correlation number is effective and efficient for real-time detection of the presence of leaks.

In this paper, TC21 titanium alloy welded joints were successfully formed through inertial friction welding (IFW) processes. Microstructure evolution of IFW joints was investigated by way of different analysis methods including optical microscope (OM), scanning electron microscope(SEM), Electron Back-Scattered Diffraction(EBSD), X-Ray Diffraction(XRD), and Energy Dispersive Spectrometer(EDS). The results indicate that large-sized equiaxial β grains, original α phases, and basketweave structure existing in the BM have completely disappeared in the WZ. Instead, fine equiaxial grains sized at 20–30 μm and very fine α + β lamellar microstructure are formed in the WZ. However, as transition zones, the microstructures of the TMAZ and HAZ are also in transition state while the microstructures existing in the BM partially remain in the TMAZ and completely remain in the HAZ. In addition, second α phases are precipitated and fine α + β lamellar microstructure are formed on the original β base in the TMAZ and HAZ. XRD and EBSD results reveal that the proportion of β phase in the WZ zone decreases greatly. EDS results show that there are aggregations of stabilizing elements of β phase in the BM, but no element aggregation in the WZ. Dynamic recrystallization during the IFW process and element distribution under the rapid cooling condition after the welding process are believed to be responsible for formation of the microstructure in the weld zone of IFW joints.

A transformer state assessment method based on an improved extreme learning machine is proposed in this paper, which introduces an adaptive evolution algorithm into the extreme learning machine. This method is used in the evaluation model to evaluate the state of the transformer. The algorithm is trained and tested through sample sets. Furthermore, the test results are analyzed to prove the feasibility of the proposed control strategy.

This paper analyzes the current common problems in substation temperature measurement, and the transformer temperature measurement system is designed. The system includes a temperature collection node, a temperature concentrator and a remote monitoring center, which can perfectly realize the functions of temperature collection, wireless transmission and online monitoring. Through the actual application of the software, it can be seen that the various modules are operating normally and have reached the design goals.

Key message Heterosis QTLs, including qSS7 and qHD8, with dominance effects were identified through GBS and large-scale phenotyping of CSSLs and hybrid F1 populations in a paddy field. Abstract Heterosis has contributed immensely to agricultural production, but its genetic basis is unclear. We evaluated dominance effects by creating two hybrid populations: a B-homo set with a homozygous background and heterozygous chromosomal segments and a B-heter set with a heterozygous background and homozygous segments. This was achieved by crossing a set of 156 backcrossed-derived chromosome segment substitution lines (CSSLs) with their recurrent parent (9311), the male parent of the first super-high-yield hybrid Liangyoupei9 (LYP9), and with the female parent (PA64s) of the hybrid. The CSSLs were subjected to a genotyping-by-sequencing analysis to develop a genetic map of segments introduced from the PA64s. We evaluated the heterotic effects on eight yield-related traits in the hybrid variety and F1 populations in large-scale field experiments over 2 years. Using a linkage map consisting of high-density SNPs, we identified heterosis-associated genes in LYP9. Five candidate genes contributed to the high yield of LYP9, with qSS7 and qHD8 repeatedly detected in both B-hybrid populations. The heterozygous segments harboring qSS7 and qHD8 showed dominance effects that contributed to the heterosis of yield components in the hybrid rice variety Liangyoupei9.

With the development of human-computer interaction technology, the interactive experience between human and machine becomes more and more simple and natural. The ideal state of human-computer interaction can be operated by natural devices such as voice, gestures and expressions, which have been tried and applied in the Kinect field. Kinect, as a new generation of motion sensing device, can achieve the input function by capturing the user’s motion and speech recognition in real time, so as to control the movement of the robot and effectively improve its intelligence. The research of this paper mainly includes skeleton tracking and robot control. Kinect1 generation was used to obtain the human body depth and skeleton images. VS software was used for programming. OpenNI and Kinect SDK libraries were called to identify the human arm joints and obtain the spatial coordinates. The robot controller USES the STMF series 32-bit processor, accepts serial port data, controls the robot arm steering gear, and completes the human body movement imitation. The motion trajectory is smooth and stable, and the motion effect is good.

An ultralow-loss silicon planar waveguide crossing operating in the O-band was experimentally demonstrated based on the Gaussian beam synthesis method. Elliptical parabolic inverted tapers were introduced in our design to reduce the crossing loss. According to the measurement results, the proposed device exhibits an insertion loss of 0.008 dB, which is the lowest reported loss for planar silicon waveguide crossings operating in the O-band. The device exhibits a low crosstalk below -40 dB over a 40 nm wavelength range with a compact footprint of 18 × 18 µm2 and can be fabricated in a complementary metal-oxide-semiconductor-compatible process.

Predicting the dynamic behavior of coexisting ions on mineral interface is essential to understanding their lability in soil matrix, but a mechanical kinetic model for predicting competitive adsorption is lacking. In this study, the thermodynamic and kinetic adsorption behaviors of Ni(II), Co(II), Cr(VI), and P(V) on goethite under various condition were investigated by batch and stirred-flow experiments, respectively. The equilibrium model CD-MUSIC was developed to describe their equilibrium behavior, followed by the development of a multi-rate kinetic model constrained by the equilibrium model to describe their kinetic behavior. Ni(II) and Co(II) exhibit similar adsorption affinities, while the adsorption of P(V) was stronger and faster than that of Cr(VI). The two surface species of Cr(VI) and P(V) differed in dynamic features, a finding confirmed by in-situ ATR-FTIR spectroscopy. The kinetic model was successfully used to predict the binary competitive adsorption of Ni(II)-Co(II) and Cr(VI)-P(V), and especially the overshooting of Cr(VI) induced by P(V). Our results showed that an integrated thermodynamic-kinetic model obtained from a single-ion experiment can be extended to describe complex multi-ion interactions, indicating the robustness and scalability of the model’s parameters. This approach can be used to construct more comprehensive equilibrium and dynamic models of the actual soil environment.

Spectroscopy is an efficient way to estimate the chlorophyll content of crop canopy in the visible and near-infrared region to indicate the photosynthesis capacity and growth status. Although hyperspectral data of crop canopy provide a lot of information, a critical issue is that the subsequent redundant and interference wavelengths could reduce the accuracy and robustness of the estimated results in the field. Therefore, a cascade method of interval-wavelength screening was proposed to reduce the data dimension and improve the crop estimation accuracy and robustness for the chlorophyll content diagnosis of maize crops. In the experiments, spectral reflectance data of maize canopy within 325–1075 nm were obtained, and chlorophyll contents were measured under the conditions of six nitrogen application rates and three growth periods following the early flaring, flaring, and tasseling stages. First, the backward interval partial least squares (BiPLS) method was used to optimize the spectrum interval. Then, competitive adaptive reweighted sampling (CARS) and genetic algorithm (GA) were used for secondary wavelength screening, and the partial least squares regression (Bi-CARS-PLSR and Bi-GA-PLSR) model was established with the chlorophyll content. Compared with the full-spectrum modeling (Full-PLSR) results and the GA and CARS screening wavelength modeling (Full-CARS-PLSR and Full-GA-PLSR) results in the full-spectrum range, the number of wavelengths in the Full-PLSR model was 751. The accuracy of the Full-PLSR model with the coefficient of determination was 0.88 for the calibration set (Rc2) and 0.66 for the verification set (Rv2). The root mean square error (RMSE) was 2.05 mg/L. The wavelength numbers of Full-CARS-PLSR and Full-GA-PLSR were 125 and 99, and their Rc2 and Rv2 were 0.88 and 0.67, respectively. The RMSE values of Full-CARS-PLSR and Full-GA-PLSR were 2.04 and 1.89 mg/L, respectively. By using the proposed cascade method, the wavelength numbers of the Bi-CARS-PLSR model and Bi-GA-PLSR model after interval optimization were 60 and 49, respectively. Their accuracy values for the calibration set (Rc2) were both 0.87, while those for the verification set (Rv2) were 0.7 and 0.78, respectively. The RMSE values of both models were 1.97 and 1.86 mg/L, respectively. The results showed that the proposed cascaded interval-wavelength screening method could eliminate redundant and collinearity variables and improve model performances. At the same time, the Bi-GA-PLSR modeling result was used for field prediction to establish a chlorophyll distribution map, which had a high consistency with the real chlorophyll distribution, and showed the potential to detect chlorophyll content of maize in the field.

Quantum random number generators (QRNGs) can produce true random numbers. Yet, the two most important QRNG parameters highly desired for practical applications, i.e., speed and size, have to be compromised during implementations. Here, we present the fastest and miniaturized QRNG with a record real-time output rate as high as 18.8 Gbps by combining a photonic integrated chip and the technology of optimized randomness extraction. We assemble the photonic integrated circuit designed for vacuum state QRNG implementation, InGaAs homodyne detector and high-bandwidth transimpedance amplifier into a single chip using hybrid packaging, which exhibits the excellent characteristics of integration and high-frequency response. With a sample rate of 2.5 GSa/s in a 10-bit analog-to-digital converter and subsequent paralleled postprocessing in a field programmable gate array, the QRNG outputs ultrafast random bitstreams via a fiber optic transceiver, whose real-time speed is validated in a personal computer., Comment: 5 pages, 4 figures. Accepted for publication in Applied Physics Letters

Nitrate (NO3&minus, ) and ammonium (NH4+) are the main inorganic nitrogen (N) sources absorbed by oilseed rape, a plant that exhibits genotypic differences in N efficiency. In our previous study, the biomass, N accumulation, and root architecture of two oilseed rape cultivars, Xiangyou 15 (high N efficiency, denoted &ldquo, 15&rdquo, ) and 814 (low N efficiency, denoted &ldquo, 814&rdquo, ), were inhibited under NH4+ nutrition, though both cultivars grew normally under NO3&minus, nutrition. To gain insight into the underlying molecular mechanisms, transcriptomic changes were investigated in the roots of 15 and 814 plants subjected to nitrogen-free (control, CK), NO3&minus, (NT), and NH4+ (AT) treatments at the seedling stage. A total of 14,355 differentially expressed genes (DEGs) were identified. Among the enriched Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway categories of these DEGs, carbohydrate metabolism, lipid metabolism, protein metabolism, and cell wall biogenesis were inhibited by AT treatment. Interestingly, DEGs such as N transporters, genes involved in N assimilation and CESA genes related to cellulose synthase were also mostly downregulated in the AT treatment group. This downregulation of genes related to crucial metabolic pathways resulted in inhibition of oilseed rape growth after AT treatment.

Association analysis between constructed single nucleotide polymorphism linkage disequilibrium blocks (SNPLDBs) and general combining ability (GCA) effects is a novel approach to uncover the genetic basis of GCA within the sequence genomes of parents of hybrid rice. Here, we calculated the GCA effect values of 33 parents of hybrid rice and sequenced them to identify genome-wide single nucleotide polymorphisms (SNPs). In total, 64.6 % of the uniquely mapped paired-end short reads revealed a final total of 291 959 SNPs between the 33 parental genomes and the Nipponbare reference genome. The identified SNPs were non-randomly distributed among all chromosomes of rice, whereas one-fourth of the SNPs were situated in the exonic regions with 16 % being non-synonymous. Further, the identified SNPs were merged and optimized for construction of 2612 SNPLDB markers, using linkage disequilibrium information. The single-factor analysis of variance-based association method between the constructed SNPLDB markers and GCA effects values detected 99 significant SNPLDBs for GCA of 11 yield-related traits. The associated SNPLDB markers explained 26.4 % of phenotypic variations with traits, on average. We mined 50 favourable GCA alleles at the associated SNPLDBs regions, distributed across the 33 parental genomes. The parental genomes possessed a small number of favourable GCA alleles for studied traits, with the exception of days to heading and plant height. Our results suggest that the identified GCA alleles could be used to improve the GCA performance of parents of hybrid rice through optimal crossing design. Moreover, favourable GCA alleles should be incorporated in the parental genomes through marker-assisted selection experiments, and the parental lines carrying more alleles could be utilized in breeding as superior parents for developing rice hybrids of desirable characteristics., We calculated the GCA values of 33 parents of hybrid rice and sequenced them to identify SNPs. In total, 64.6 % of the uniquely mapped paired-end reads revealed a final total of 291 959 SNPs between the 33 parents and the Nipponbare reference. The identified SNPs were non-randomly distributed, whereas one-fourth of the SNPs were situated in the exonic regions with 16 % being non-synonymous. The identified SNPs were optimized for construction of 2612 SNPLDB markers, using linkage disequilibrium. The association between SNPLDB markers and GCA values detected 99 significant SNPLDBs of GCA having 26.4 % of phenotypic variations.

The graded treatment system refers to the gradation of diseases according to their priority and ease of treatment, with medical institutions at different levels undertaking the treatment of different diseases and gradually realizing the medical process from general practice to specialization. Since the “new medical reform”, China has been committed to promoting “primary care”, “two-way referral”, “separation of acute and slow treatment” The “new health care reform” has been implemented in China since the beginning of the reform. However, in the process of implementation, the effectiveness of the system has always been controversial due to the inadequate construction of primary medical institutions and the weak awareness of graded treatment among residents.

As electrolytic capacitor is apt to fail in power converters, it is very important to monitor its electrical parameters, mainly the equivalent series resistance (ESR) and capacitance (C). A novel non-invasive online monitoring method of DC-link capacitor's ESR and C for boost power factor correction (PFC) converter is proposed in this paper. By analyzing the capacitor voltage ripple which is composed of that of ESR and C, the calculation model is founded, which shows that instead of additional current sensor, only two values of capacitor voltage in particular moments within a line cycle need to be sampled for the calculation of ESR and C. The schematic of the monitoring system together with the design considerations of the trigger circuit, the isolated voltage amplifier, the isolated current amplifier are described in detail. The experimental results show the effectiveness of the method.

As electrolytic capacitor is apt to fail in power circuits, it is very important to identify its electrical parameters, mainly the equivalent series resistance (ESR) and capacitance ( C ). A noninvasive online identification method of capacitor's ESR and C for continuous-conduction-mode (CCM) buck converter is proposed in this paper. Based on the ac component of capacitor voltage, the calculation model is founded. By sampling the pulse width modulation signal and output voltage, the method needs no current sensor and is effective for the CCM buck converter operating at different conditions. Implementation of the identification system is presented. The tests are carried out for different aged capacitors and ambient temperatures. The experimental results validate the effectiveness of the method.

Mesh plays an indispensable role in dense real-time reconstruction essential in robotics. Efforts have been made to maintain flexible data structures for 3D data fusion, yet an efficient incremental framework specifically designed for online mesh storage and manipulation is missing. We propose a novel framework to compactly generate, update, and refine mesh for scene reconstruction upon a volumetric representation. Maintaining a spatial-hashed field of cubes, we distribute vertices with continuous value on discrete edges that support O(1) vertex accessing and forbid memory redundancy. By introducing Hamming distance in mesh refinement, we further improve the mesh quality regarding the triangle type consistency with a low cost. Lock-based and lock-free operations were applied to avoid thread conflicts in GPU parallel computation. Experiments demonstrate that the mesh memory consumption is significantly reduced while the running speed is kept in the online reconstruction process., Accepted to ICRA 2018

With a limited number of built-in power monitors to detect the optimum operating points of all switch units, we demonstrated a 32 × 32 MZI-based silicon electro-optical switch operating with nanosecond speeds.

To construct large-scale silicon electro-optical switches for optical interconnections, we developed a method using a limited number of power monitors inserted at certain positions to detect and determine the optimum operating points of all switch units to eliminate non-uniform effects arising from fabrication errors. We also introduced an optical phase bias to one phase-shifter arm of a Mach–Zehnder interferometer (MZI)-type switch unit to balance the two operation statuses of a silicon electro-optical switch during push–pull operation. With these methods, a 32 × 32 MZI-based silicon electro-optical switch was successfully fabricated with 180-nm complementary metal–oxide–semiconductor (CMOS) process technology, which is the largest scale silicon electro-optical switch to the best of our knowledge. At a wavelength of 1520 nm, the on-chip insertion losses were 12.9 to 16.5 dB, and the crosstalk ranged from −17.9 to −24.8 dB when all units were set to the ‘Cross’ status. The losses were 14.4 to 18.5 dB, and the crosstalk ranged from −15.1 to −19.0 dB when all units were in the ‘Bar’ status. The total power consumptions of the 32 × 32 switch were 247.4 and 542.3 mW when all units were set to the ‘Cross’ and ‘Bar’ statuses, respectively.

Heterosis or hybrid vigor is closely related with general combing ability (GCA) of parents and special combining ability (SCA) of combinations. The evaluation of GCA and SCA facilitate selection of parents and combinations in heterosis breeding. In order to improve combining ability (CA) by molecular marker assist selection, it is necessary to identify marker loci associated with the CA. To identify the single nucleotide polymorphisms (SNP) loci associated with CA in the parental genomes of japonica rice, genome-wide discovered SNP loci were tested for association with the CA of 18 parents for 12 yield-related traits. In this study, 81 hybrids were created and evaluated to calculate the CA of 18 parents. The parents were sequenced by genotyping by sequencing (GBS) method for identification of genome-wide SNPs. The analysis of genotyping by sequencing indicated that the successful mapping of 9.86×106 short reads in the Nipponbare reference genome consists of 39,001 SNPs in parental genomes at 11,085 chromosomal positions. The discovered SNPs were non-randomly distributed within and among the 12 chromosomes of rice. Overall, 20.4% (8026) of the discovered SNPs were coding types, and 8.6% (3344) and 9.9% (3951) of the SNPs revealed synonymous and non-synonymous changes, which provide valuable knowledge about the underlying performance of the parents. Furthermore, the associations between SNPs and CA indicated that 362 SNP loci were significantly related to the CA of 12 parental traits. The identified SNP loci of CA in our study were distributed genome wide and caused a positive or negative effect on the CA of traits. For the yield-related traits, such as grain thickness, days to heading, panicle length, grain length and 1000-grain weight, a maximum number of positive SNP loci of CA were found in CMS A171 and in the restorers LC64 and LR27. On an individual basis, some of associated loci that resided on chromosomes 2, 5, 7, 9, and 11 recorded maximum positive values for the CA of traits. From our results, we suggest that heterosis in japonica rice would be improved by pyramiding the favorable SNP loci of CA and eliminating the unfavorable loci from parental genomes.

We have synthesized a new catalyst based on thiol-functionalized silica-coated magnetic mesoporous nanocrystals as support and Au nanoparticles as active sites through a facile and environment-friendly approach and characterized by transmission electron microscopy (TEM), N 2 adsorption–desorption, elemental analysis and inductive coupled plasma atomic emission spectrometer (ICP-AES), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and vibrating sample magnetometry (VSM). The synthesized catalyst exhibited high catalytic activity in the oxidations of cyclohexene and styrene by molecular oxygen at atmospheric pressure. Furthermore, this catalyst had an excellent recyclability, evidenced by being extensively reused for five times without any substantial loss of activity, which was mainly attributed to the enough strong combination between the Au nanoparticles and thiol groups onto the surface of support. Meanwhile, the catalyst could be easily separated from the reaction solution by applying an external magnetic field.

In this work, a novel catalyst Fe@Pd/C was synthesized by sequential reduction method. The core–shell catalyst exhibited efficient catalytic activity in Suzuki coupling reaction at mild condition in water. Moreover, the catalyst could be recycled by external magnetic field and the yields achieved above 86% after reused at least 5 times.

A high-performance Ni1−xFex on polyethyleneimine (PEI)-functionalized molybdenum disulfide (MoS2) electrocatalyst has been synthesized by an electroplating in situ growth approach. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy confirm the successful functionalization of MoS2 with PEI. The empty orbitals of Ni2+ and Fe2+ (Ni and Fe precursors) coordinated with the donated lone pairs of nitrogen atoms in PEI-mediated MoS2 and then the Ni2+ and Fe2+ were in situ reduced at a negative potential. Transmission electron microscope images and X-ray diffraction reveal that Ni85Fe15 nanoparticles with an average size of 2.25 nm are uniformly dispersed on the PEI–MoS2 sheets. The Ni1−xFex/PEI–MoS2 catalyst exhibits unexpectedly high activity towards the hydrazine oxidation reaction, which can be attributed to highly homogeneous dispersed Ni1−xFex alloy. It also shows enhanced electrochemical stability due to the structural integrity of PEI–MoS2. Finally, the Ni85Fe15/PEI–MoS2 catalyst is proved to be very valuable for applications in hydrazine fuel cells, as compared with Ni90Fe10/PANi–MoS2 and Ni85Fe15/MoS2 catalysts.

For the first time, Cu nanoparticles were evenly decorated on MoS2 nanosheet by chemical reduction. The as-prepared Cu-MoS2 hybrid was characterized by atomic force microscope (AFM), Raman spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD) and then used to fabricate a non-enzymatic glucose sensor. The performance of our sensor was investigated by cyclic voltammetry and amperometric measurement in alkaline media. Electrochemical tests showed that Cu-MoS2 hybrid exhibited synergistic electrocatalytic activity on the oxidation of glucose with a high sensitivity of 1055 mu A mM(-1) cm(-2) and a linear range up to 4 mM. Crown Copyright (C) 2013 Published by Elsevier Ltd. All rights reserved.

Large-scale optical switches are greatly demanded in building optical interconnections in data centers and high performance computers (HPCs). Silicon optical switches have advantages of being compact and CMOS process compatible, which can be easily monolithically integrated. However, there are difficulties to construct large ports silicon optical switches. One of them is the non-uniformity of the switch units in large scale silicon optical switches, which arises from the fabrication error and causes confusion in finding the unit optimum operation points. In this paper, we proposed a method to detect the optimum operating point in large scale switch with limited build-in power monitors. We also propose methods for improving the unbalanced crosstalk of cross/bar states in silicon electro-optical MZI switches and insertion losses. Our recent progress in large scale silicon optical switches, including 64 × 64 thermal-optical and 32 × 32 electro-optical switches will be introduced. To the best our knowledge, both of them are the largest scale silicon optical switches in their sections, respectively. The switches were fabricated on 340-nm SOI substrates with CMOS 180- nm processes. The crosstalk of the 32 × 32 electro-optic switch was -19.2dB to -25.1 dB, while the value of the 64 × 64 thermal-optic switch was -30 dB to -48.3 dB.

32 × 32 electro-optic and 64 × 64 thermal-optic Mach-Zehnder interferometer (MZI)-based switches were demonstrated using a 180-nm CMOS process. To the best of our knowledge, both switches that were demonstrated were the largest-scale electro-optic and thermal-optical silicon switches available.

OsPPR6, a pentatricopeptide repeat protein involved in editing and splicing chloroplast RNA, is required for chloroplast biogenesis in rice. The chloroplast has its own genetic material and genetic system, but it is also regulated by nuclear-encoded genes. However, little is known about nuclear-plastid regulatory mechanisms underlying early chloroplast biogenesis in rice. In this study, we isolated and characterized a mutant, osppr6, that showed early chloroplast developmental defects leading to albino leaves and seedling death. We found that the osppr6 mutant failed to form thylakoid membranes. Using map-based cloning and complementation tests, we determined that OsPPR6 encoded a new Pentatricopeptide Repeat (PPR) protein localized in plastids. In the osppr6 mutants, mRNA levels of plastidic genes transcribed by the plastid-encoded RNA polymerase decreased, while those of genes transcribed by the nuclear-encoded RNA polymerase increased. Western blot analyses validated these expression results. We further investigated plastidic RNA editing and splicing in the osppr6 mutants and found that the ndhB transcript was mis-edited and the ycf3 transcript was mis-spliced. Therefore, we demonstrate that OsPPR6, a PPR protein, regulates early chloroplast biogenesis and participates in editing of ndhB and splicing of ycf3 transcripts in rice.

Heterosis or hybrid vigor is closely related with general combing ability (GCA) of parents and special combining ability (SCA) of combinations. The evaluation of GCA and SCA facilitate selection of parents and combinations in heterosis breeding. In order to improve combining ability (CA) by molecular marker assist selection, it is necessary to identify marker loci associated with the CA. To identify the single nucleotide polymorphisms (SNP) loci associated with CA in the parental genomes of japonica rice, genome-wide discovered SNP loci were tested for association with the CA of 18 parents for 12 yield-related traits. In this study, 81 hybrids were created and evaluated to calculate the CA of 18 parents. The parents were sequenced by genotyping by sequencing (GBS) method for identification of genome-wide SNPs. The analysis of GBS indicated that the successful mapping of 9.86 × 106 short reads in the Nipponbare reference genome consists of 39,001 SNPs in parental genomes at 11,085 chromosomal positions. The discovered SNPs were non-randomly distributed within and among the 12 chromosomes of rice. Overall, 20.4% (8026) of the discovered SNPs were coding types, and 8.6% (3344) and 9.9% (3951) of the SNPs revealed synonymous and non-synonymous changes, which provide valuable knowledge about the underlying performance of the parents. Furthermore, the associations between SNPs and CA indicated that 362 SNP loci were significantly related to the CA of 12 parental traits. The identified SNP loci of CA in our study were distributed genome wide and caused a positive or negative effect on the CA of traits. For the yield-related traits, such as grain thickness, days to heading, panicle length, grain length and 1000-grain weight, a maximum number of positive SNP loci of CA were found in CMS A171 and in the restorers LC64 and LR27. On an individual basis, some of associated loci that resided on chromosomes 2, 5, 7, 9, and 11 recorded maximum positive values for the CA of traits. From our results, we suggest that heterosis in japonica rice would be improved by pyramiding the favorable SNP loci of CA and eliminating the unfavorable loci from parental genomes.

Background Single-nucleotide polymorphisms (SNPs) have become the genetic markers of choice in various genetic, ecological, and evolutionary studies. Genotyping-by-sequencing (GBS) is a next-generation-sequencing based method that takes advantage of reduced representation to enable high-throughput genotyping using a large number of SNP markers. Results In the present study, the distribution of non-redundant SNPs in the parents of 12 rice recombination line populations was evaluated through GBS. A total of 45 Gigabites of nucleotide sequences conservatively provided satisfactory genotyping of rice SNPs. By assembling to the genomes of reference genomes of japonica Nipponbare, we detected 22,682 polymorphic SNPs that may be utilized for QTL/gene mapping with the Recombinant Inbred Lines (RIL) populations derived from these parental lines. Meanwhile, we identified polymorphic SNPs with large effects on protein-coding and miRNA genes. To validate the effect of the polymorphic SNPs, we further investigated a SNP (chr4:28,894,757) at the miRNA binding site in the 3′-UTR region of the locus Os4g48460, which is associated with rice seed size. Os4g48460 encodes a putative cytochrome P450, CYP704A3. Direct degradation of the 3′-UTR of the CYP704A3 gene by a miRNA (osa-miRf10422-akr) was validated by in planta mRNA degradation assay. We also showed that rice seeds of longer lengths may be produced by downregulating CYP704A3 via RNAi. Conclusions Our study has identified the genome-wide SNPs by GBS of the parental varieties of RIL populations and identified CYP704A3, a miRNA-regulated gene that is responsible for rice seed length. Electronic supplementary material The online version of this article (doi:10.1186/s12870-016-0779-3) contains supplementary material, which is available to authorized users.

A non-blocking 16×16 silicon electro-optic switch based on Benes network was demonstrated. The extinction ratios of the switch are 20.2∼29.8 dB. It consists of 56 MZI switch units, whose switching time are 1 nanosecond.

An optical time-domain reflectometer (OTDR) based on silicon oxynitride (SiON) waveguides was demonstrated to have a dynamic range of 10 dB. The compact OTDR optical device was fabricated with III-V/Si hybrid integration technology.

Nanostructured zirconia thermal barrier coatings (TBCs) have been prepared by atmospheric plasma spraying using the reconstituted nanosized yttria partially stabilized zirconia powder. Field emission scanning electron microscope was applied to examine the microstructure of the resulting TBCs. The results showed that the TBCs exhibited a unique, complex structure including nonmelted or partially melted nanosized particles and columnar grains. A CO2 continuous wave laser beam has been applied to laser glaze the nanostructured zirconia TBCs. The effect of laser energy density on the microstructure and thermal shock resistance of the as-glazed coatings has been systematically investigated. SEM observation indicated that the microstructure of the as-glazed coatings was very different from the microstructure of the as-sprayed nanostructured TBCs. It changed from single columnar grain to a combination of columnar grains in the fracture surface and equiaxed grains on the surface with increasing laser energy density. Thermal shock resistance tests have showed that laser glazing can double the lifetime of TBCs. The failure of the as-glazed coatings was mainly due to the thermal stress caused by the thermal expansion coefficient mismatch between the ceramic coat and metallic substrate.

The increases in the usage of nitrogen fertilizer result in deleterious impacts on the environment; thus, there is an urgent need to improve nitrogen use efficiency (NUE) in crops including rice (Oryza sativa L.). Attentions have focused on quantitative trait loci (QTL) mapping of NUE-related traits using single experimental population, but to date, very few studies have taken advantage of association mapping to examine hundreds of lines for identifying potentially novel QTLs in rice. Here, we conducted association analysis on NUE-related traits using a population containing 184 varieties, which were genotyped with 157 genome-wide simple sequence repeat (SSR) markers. We detected eight statistically significant marker loci associating with NUE-related traits, of which two QTLs at RM5639 and RM3628 harbored known NUE-related genes GS1;2 and AspAt3, respectively. At a novel NUE-related locus RM5748, we developed Kompetitive Allele Specific PCR (KASP) single nucleotide polymorphism (SNP) markers and searched for putative NUE-related genes which are close to the associated SNP marker. Based on a transcriptional map of N stress responses constructed by our lab, we evaluated expressions of the NUE-related genes in this region and validated their effect on NUE. Meanwhile, we analyzed NUE-related alleles of the eight loci that could be utilized in marker-assisted selection. Moreover, we estimated breeding values of all the varieties through genomic prediction approach that could be beneficial for rice NUE enhancement.

A re-arrangeable non-blocking 8×8 silicon electro-optic switch was demonstrated. It had extinction ratios of 18.3∼25.5dB on all "Cross" status and 13.3∼19dB on all "Bar" status at 1550nm.

A high-speed non-blocking silicon 8×8 switch matrix was demonstrated based on Benes network and carrier-dispersion electro-optic controlling. The extinction ratios are 18.3∼25.5dB on “all-Cross” and 13.3∼19.0dB on “all-Bar” status at 1550nm.

In power factor correction (PFC) converter, an electrolytic capacitor (E-Cap) is usually used, which has the shortest lifetime. The mathematical relationship between the root mean square (RMS) value of E-Cap's ripple current and the converter's parameters are derived in this paper for DCM boost PFC converter. The corresponding 3rd input current harmonic is figured out for the optimal reduction of the ripple current RMS value so that the E-Cap's lifetime can be greatly improved. A method of fitting the variable duty cycle and the simplified circuit implementation are further proposed. Compared with the constant duty cycle control (CDC), the variable duty cycle control (VDC) also achieves efficiency improvement as the critical inductance is increased and the peak and RMS current value of the power components are therefore decreased. The experimental results from a prototype of 120W are given to verify the effectiveness of the analysis.

Three-phase single-switch boost power factor correction (PFC) converter features zero-current turn-on for the switch, no reverse recovery in diode, constant frequency operation, simple control and low cost. That makes it suitable for low-to-medium power and cost-sensitive applications. Due to Discontinuous current mode (DCM), energy transfer does not cover the whole switching cycle, the rms and peak values of the inductor current is large which will increase the conduction and switching turn-off loss, resulting a lower efficiency of the converter. An optimum utilization control of switching cycles (OUCSC) is proposed in this paper so as to increase the critical boost inductance. A larger inductance is helpful for reducing the rms and peak current values of the main power components which will lower the conduction and switching turn-off loss, leading to a higher efficiency. The proposed method also achieves the output voltage ripple or the output storage capacitance reduction. And the harmonics comply with IEC 61000-3-2 Class A regulations.

As substitutions for transition metal oxides (MOs), transition metal carbonates (MCO3) have been attracting more and more attention because of their lithium storage ability in recent years. Is MCO3 better than MOs for lithium storage? To answer this question, monodisperse CoCO3 and CoO microspindles with comparable structures were synthesized and investigated as a case study. Excluding its structural effect, we found CoCO3 still exhibited reversible capacities and rate capabilities much higher than those of CoO. The reversible capacity of CoCO3 after 10 cycles was 1065 mAh g(-1), 48.2% higher than that (∼720 mAh g(-1)) of CoO. Furthermore, the greatly different electrochemical behaviors were investigated by analyzing the discharge-charge profiles, cyclic voltammetry curves, and Nyquist plots in depth. This work can improve our understanding of the lithium storage advantages of MCO3 against MOs and enlighten us in terms of developing high-performance MCO3 with favorable structures.

The terminal loop region of primary miRNA transcripts is an important determinant controlling miRNA function in human, animals and plants. However, the effects of polymorphisms in loop region of miRNA precusors on phenotypic variation have not been reported, especially on agronomic traits in rice. From rice japonica variety Koshihikari and indica Guichao2, we isolated a precursor of putative miRNA osa-MIR2923a. We detected a GG/AA polymorphism in the loop structure from japonica and indica rice varieties, which was corresponding to japonica/indica rice differentiation. By using high-resolution melting (HRM) analysis, we measured the polymorphisms in a RIL (recombinant inbred lines) population derived from japonica variety Koshihikari and indica Guichao2. We found that the GG/AA polymorphism in the osa-MIR2923a loop was correlated to grain length and length-width ratio. We further found the significant association between seed length and GG/AA polymorphism in a population consisting of 72 rice landraces. Three targets were predicted, whose expressions showed significant differences between the two varieties. Our results suggested that the putative miRNA precursor and the three target genes could play functional roles for indica/japonica seed differentiation.

A new type of composite brush which consists of property-modified graphite matrix and copper plated carbon fiber has been investigated. These brushes possess high current carrying capacity, excellent commutating performance and good wearing resistance as well as performance designability. In order to adapt different kinds of electrical machines such as 55 kW DC machine, 600,000 kW turbogenerator, 60 kW traction motor and 800 kW rolling machine, varied composite brushes were optimally designed by pretreating the fibers, modifying the graphite matrix and changing the distribution of the fibers. Results indicated an excellent performance of these brushes. For instance, the comparisons of composite brushes with commercial electrographite brush after more than 1200 hours dynamic test on a 551 kW DC machine showed that the current density had been increased by 4 times (0.36 MA/m/sup 2/), the width of the no sparking zone had been enlarged by 2-9 times and the mechanical loss had been decreased by 15-25%. In the meantime, the wear of the commutator was as usual. It means that such fiber composite brushes have great potential in improving the performance and structure of electrical machines.