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In order to achieve metallurgical bonding in the form of solid solution at the Cu/W interface and avoid the formation of intermetallic compounds, the novel high entropy alloys (HEAs) were designed on the basis of the mature high entropy alloy criteria. The CuCrCoFeNixTi high entropy alloys interlayers were applied to weld the CuW and CuCr bimetals by sintering–infiltration technology. Scanning electron microscope, energy dispersive spectrometry, and X-ray diffraction were used to explore the interfacial microstructure evolutions and strengthening mechanism of CuW/CuCr joints with applied HEA interlayers. The interfacial characterization results show that HEAs were diffused and dissolved into bimetallic materials, and a diffusion solution layer of 2–3 μm thickness was formed at the Cu/W phase interface, and there is no new phase generated at the CuW/CuCr interface. When CuCrCoFeNi1.5Ti interlayer was infiltrated into the CuW/CuCr interface, the electrical conductivity of CuCr side is 71.6%IACS, and the interfacial tensile strength reaches 484.5 MPa. Compared with the CuW/CuCr integral material without interlayer, the interfacial bonding strength is increased by 43.1%. And the SEM fracture morphology presents a larger amount of cleavage fractures of W particles. It indicates the appropriate solid solution layer on edge of W skeletons formed at the Cu/W phases interface. The Cu/W phase interface is strengthened, and it can effectively transfer and disperse the external load. Tungsten phase with higher elastic modulus endures a large amount of load, resulting in enhancing the CuW/CuCr interfacial bonding strength. When CuCrCoFeNi2Ti high entropy alloy interlayer was applied, the W skeleton near the CuW/CuCr interface was eroded, the imperfect W skeleton cannot withstand the tensile load effectively, resulting in decrease in the CuW/CuCr interfacial bonding strength. In the interfacial fracture, appears some fragmentations of W particles, and fewer W particles occur at the cleavage fracture.

Hydrogen-induced embrittlement is a significant safety concern for steel pipelines used in the transmission of hydrogen-blended natural gas. To mitigate this issue, hydrogen barrier coatings can be applied to the surface of steel substrates to reduce hydrogen permeation. In this study, rare earth oxides were optimized via first-principles calculations to identify the most effective doping agents. Subsequently, a FexAly/Al/Al2O3 composite coating doped with La2O3 and Ce2O3 was successfully applied to the surface of X80 steel using hot-dip aluminum plating combined with anodic oxidation. The coating was characterized using various techniques, including SEM, EDS, XRD, XPS, and hydrogen permeation tests. The results demonstrated that co-doping La2O3 and Ce2O3 resulted in a lower adsorption energy of Al2O3 to hydrogen molecules, and improved the surface quality of the aluminizing layer and the composite coating. Electrochemical hydrogen permeation tests showed that the FexAly/Al/Al2O3 composite coating significantly improved the hydrogen barrier property of X80 steel. The anodizing current density was found to have a significant effect on the coating's morphology, which in turn affected the hydrogen barrier property of the coating. The composite coating obtained at an anodizing current density of 2 A/dm2 was uniform and dense, without noticeable defects, and exhibited the best hydrogen barrier property. [ABSTRACT FROM AUTHOR]

When dealing with safety‐critical applications that involve multiphase permanent magnet synchronous motors (PMSMs), the current source inverter (CSI) is a superior choice compared with the voltage source inverter. The conventional technique of pulse width modulation (PWM) presents a challenge for CSI, particularly during faults. The fault‐tolerant control of multiphase PMSMs fed by CSIs has not been well investigated, particularly in situations involving double‐phase open‐circuit faults. Furthermore, fault‐tolerant control becomes more complex when the multiphase PMSM includes harmonic back electromotive forces (EMFs). To deal with these issues, an ampere‐second (AS) vector PWM technique is developed for a five‐phase PMSM powered by CSI11. The modulation ratio of the proposed PWM is identical to that of space vector PWM. The proposed method, however, is easier to implement. A fault‐tolerant control method using AS‐vector is proposed for single‐phase, adjacent double‐phase, and non‐adjacent double‐phase open‐circuit faults. Additionally, a method is developed to suppress the torque ripple that results from harmonic back‐EMFs during fault conditions. Compared without the torque ripple suppression method, during the speed rising, the proposed method can reduce torque ripple to 16.7%, 54.5%, and 37.5%, respectively. The experiments have confirmed the effectiveness of the proposed PWM technique and fault‐tolerant control method. [ABSTRACT FROM AUTHOR]

This study presents a detailed numerical investigation into the web buckling behaviour exhibited by high-strength aluminium alloy channels, namely 7075-T6 and AA-6086, when subjected to concentrated loading. A nonlinear finite element (FE) model was established and verified using the experimental data reported by other researchers, and the material properties of 7075-T6 and AA-6086 high-strength aluminium alloy were obtained through the literature. A parametric study comprising 1024 models was performed using the validated FE models. Variables examined in this work included web slenderness ratio, internal corner radii, bearing lengths, and aluminium alloy grades. The numerical results generated by the parametric investigation were used to evaluate the applicability and reliability of the most recent design specifications given in the Australian and New Zealand Standards (AS/NZ S4600) (2018) and Australian Standards (AS/NZS 1664.1) (1997). The comparison indicated that the calculated design strength using AS/NZ S4600 was over-conservative by 41% and 43% for 7075-T6 and AA-6086 aluminium alloy, correspondingly, while the design strength computed using AS/NZS 1664.1 was marginally unconservative, compared to numerical results. Finally, using bivariate linear regression analysis, new design formulas with new coefficients for determining the web buckling behaviour of 7075-T6 and AA-6086 high-strength aluminium alloy channels were proposed. A reliability analysis was then undertaken, indicating that the proposed design equations possess the capability of accurately predicting the web buckling behaviour of these members. [ABSTRACT FROM AUTHOR]

Recently, new types of C-shaped members made from AA-6086 and 7075-T6 high-strength aluminium alloy have become more popular due to their high yield strength and lower cost. These members are often manufactured with pre-punched web perforations to simplify the installation of services, but this can reduce their strength. Also, such aluminium C-shaped members that contain perforated webs are vulnerable to web buckling failure, as aluminium alloy has a lower elastic modulus compared to steel. However, this influence has not been investigated for high-strength aluminium alloy sections to date. An extensive numerical investigation was undertaken to examine the effect of web perforations on the web buckling resistance of high-strength aluminium alloy C-shaped members under an end-two-flange (ETF) loading case, and this study focused on two types of aluminium alloys, namely 7075-T6 and AA-6086. To achieve this, a nonlinear finite element (FE) model was developed and validated using the test data in the literature. The material properties used in the FE models were obtained from the relevant literature. A parametric investigation was carried out, consisting of a total of 1458 models. In this investigation, a number of variables were examined, including the web hole size, web hole location, bearing length, fillet radius and aluminium alloy grades. The results showed that increasing the a/h ratio from 0.1 to 0.5 resulted in a decrease of 9.7% and 9.3% in the web buckling resistance for the 7075-T6 aluminium and AA-6086 aluminium, respectively. When the length of the bearing plates (N) varied from 100 mm to 200 mm, the web buckling resistance experienced an average increase of 61.7% for the 7075-T6 aluminium and 54.1% for the AA-6086 aluminium. Also, the web buckling resistance increased by 6.2% for the 7075-T6 aluminium alloy, while the strength increased by 4.0% for the AA-6086 aluminium alloy when the x/h ratio increased from 0.1 to 0.5. The numerical data generated from the parametric study were used to assess the accuracy and suitability of the latest design recommendations, and it was found that the design rules presented in the previous literature cannot provide reliable and safe predictions for estimating the web buckling resistance of aluminium C-shaped members that contain perforated webs under an ETF loading case. Finally, new design formulas were proposed in the form of strength reduction factors. A reliability assessment was then undertaken, and the results of this analysis indicated that the proposed design formulas can accurately predict the web buckling resistance of such members with perforated webs. [ABSTRACT FROM AUTHOR]

In interior permanent magnet synchronous motor (IPMSM) position‐sensorless drives, the high‐frequency (HF) square‐wave voltage injection method is often used to estimate the rotor position and speed in low‐speed range by tracking the salient polarity of the motor. In order to reduce the torque ripple caused by HF signal injection, a strategy to update the magnitude of the injected signal online by back propagation neural network is proposed in this paper. With the proposed method, the neural network can update the magnitude of the injected signal online according to the d‐axis current and the position error information. It can not only ensure the accuracy of position extraction but also effectively reduce the current harmonics caused by the injected signal, and then the torque ripple can be reduced. In addition, the proposed method is easy to implement, resulting in low computation burden. Finally, the experiments are implemented on a 1‐kW IPMSM drive. The experimental results show that compared with the conventional fixed magnitude injection, the peak‐to‐peak value of the torque ripple is reduced by nearly half along with the decrease of the injected magnitude. [ABSTRACT FROM AUTHOR]

Light detection and ranging (LiDAR) is widely used in the automotive industry as it can provide point cloud information containing precise distances. Three-dimensional (3D) object detection based on LiDAR point clouds is significant for environment perception tasks. However, feature learning for point clouds remains challenging. This paper proposes a two-stage voxel-based LiDAR 3D object detector, referred to as density-aware and neighborhood attention (DenNet), that focuses on the neighborhood information of objects. DenNet mainly integrates two modules: voxel density-aware (VDA) and neighborhood attention (NA). VDA introduces density information of the point cloud. Here, point cloud density information was added as voxel features in the voxel-based framework to alleviate the information loss during voxelization. Additionally, to extract neighbor information, the characteristics of 3D objects were analyzed for traffic scenes. The NA mechanism was adopted, which localizes the receptive field for each query to its nearest neighboring points. DenNet yielded competitive results, as compared with state-of-the-art methods, for the KITTI and One Million Scenes (ONCE) datasets; notably, it afforded an improvement of 3.96% relative to the baseline mean average precision on the more challenging ONCE dataset. [ABSTRACT FROM AUTHOR]

Purpose. To analyse the clinical efficacy of biofeedback electrical stimulation combined with doxycycline in the treatment of type IIIA chronic prostatitis. Methods. Eighty patients who met the diagnostic criteria of type IIIA chronic prostatitis in our hospital between February 2020 and February 2022 were selected and equally divided into the drug group and electrical stimulation group according to the random number table method. The drug group was treated with medication alone for 4 weeks; the electrostimulation group was treated with biofeedback electrostimulation on top of medication for 12 weeks. The expressed prostatic secretious (EPS) routine (lecithin bodies, white blood cells) and the maximum urinary flow rate (Qmax) and mean urinary flow rate (Qave) were measured before and after treatment in both groups, and the National Institutes of Health chronic prostatitis symptom index (NIH-CPSI) was used to score the urinary symptom, pain or discomfort, and quality of life and determine the efficacy of the treatment in both groups. Results. After treatment, the number of lecithin bodies and white blood cells in EPS improved significantly in both groups compared to before, and both the electrical stimulation group was better than the drug group (P < 0.05). After treatment, the Qmax and Qave were significantly higher in both groups than before, and both the electrical stimulation groups were higher than the drug group (P < 0.05). After treatment, the urinary symptom scores, pain or discomfort scores, quality of life scores, and total NIH-CPSI scores were significantly lower in both groups than before, and all were lower in the electrical stimulation group than in the drug group (P < 0.05). After treatment, the overall efficiency of patients in the electrical stimulation group was significantly higher than that of the drug group (P < 0.05). Conclusion. Biofeedback electrical stimulation combined with doxycycline in the treatment of type IIIA chronic prostatitis can synergistically improve the patient's inflammation level, urinary dysfunction, relieve pelvic floor tension myalgia, and improve their quality of life, opening up new avenues for the rehabilitation of patients with type IIIA chronic prostatitis. [ABSTRACT FROM AUTHOR]

Lodging is one of the primary factors that reduce wheat yield; therefore, rapid and accurate monitoring of wheat lodging helps to provide data support for crop loss and damage response and the subsequent settlement of agricultural insurance claims. In this study, we aimed to address two problems: (1) calculating the wheat lodging area. Through comparative experiments, the SegFormer-B1 model can achieve a better segmentation effect of wheat lodging plots with a higher prediction rate and a stronger generalization ability. This model has an accuracy of 96.56%, which realizes the accurate extraction of wheat lodging plots and the relatively precise calculation of the wheat lodging area. (2) Analyzing wheat lodging areas from various growth stages. The model established, based on the mixed-stage dataset, generally outperforms those set up based on the single-stage datasets in terms of the segmentation effect. The SegFormer-B1 model established based on the mixed-stage dataset, with its mIoU reaching 89.64%, was applicable to wheat lodging monitoring throughout the whole growth cycle of wheat. [ABSTRACT FROM AUTHOR]

Among the existing harmonic current suppression methods, it is difficult and complicated to suppress any nth harmonic current accurately for multi-phase permanent magnet synchronous motors (PMSMs). To solve this problem, this paper takes a five-phase dual-rotor PMSM fed with a current source inverter (CSI) as an example, and proposes an nth harmonic current suppression method based on the impulse current PWM algorithm. Firstly, the analysis is conducted and presented for the nth harmonic current in the mth harmonic space. Then, based on the Sliding Discrete Fourier Transformation (SDFT), a low-pass filter (LPF) named SDFT-LPF is designed. Additionally, the impulse current PWM technique for the five-phase CSI is realized. In this paper, the experiments have confirmed that the SDFT-LPF has good filter performance. Compared with the SVPWM, the impulse current PWM technique has the same DC-link current utilization rate, but it is easier to implement. Moreover, the proposed harmonic current control method can accurately control any nth harmonic current without changing the PWM technique, which has significantly reduced the complexity of the harmonic current control. Additionally, the proposed scheme is easy to implement and can be directly extended to the multiple harmonic current's control. [ABSTRACT FROM AUTHOR]

HIV infection results in gastrointestinal (GI) tract damage, microbial translocation, and immune activation, which are not completely ameliorated with suppression of viremia by antiretroviral (ARV) therapy. Furthermore, increased morbidity and mortality of ARV-treated HIV-infected individuals is associated with these dysfunctions. Thus, to enhance GI tract physiology, we treated SIV-infected pigtail macaques with ARVs, probiotics, and prebiotics or with ARVs alone. This synbiotic treatment resulted in increased frequency and functionality of GI tract APCs, enhanced reconstitution and functionality of CD4+ T cells, and reduced fibrosis of lymphoid follicles in the colon. Thus, ARV synbiotic supplementation in HIV-infected individuals may improve GI tract immunity and thereby mitigate inflammatory sequelae, ultimately improving prognosis., Introduction Antiretroviral (ARV) treatment of HIV-infected individuals improves their prognosis; however, ARV-treated individuals still have increased morbidity and mortality compared with uninfected individuals (1). During progressive HIV infection of humans [...]

CD4 T follicular helper (TFH) cells interact with and stimulate the generation of antigen-specific B cells. TFH cell interaction with B cells correlates with production of SIV-specific immunoglobulins. However, the fate of TFH cells and their participation in SIV-induced antibody production is not well understood. We investigated the phenotype, function, location, and molecular signature of TFH cells in rhesus macaques. Similar to their human counterparts, TFH cells in rhesus macaques represented a heterogeneous population with respect to cytokine function. In a highly differentiated subpopulation of TFH cells, characterized by [CD150.sup.lo] expression, production of Th1 cytokines was compromised while IL-4 production was augmented, and cells exhibited decreased survival, cycling, and trafficking capacity. TFH cells exhibited a distinct gene profile that was markedly altered by SIV infection. TFH cells were infected by SIV; yet, in some animals, these cells actually accumulated during chronic SIV infection. Generalized immune activation and increased IL-6 production helped drive TFH differentiation during SIV infection. Accumulation of TFH cells was associated with increased frequency of activated germinal center B cells and SIV-specific antibodies. Therefore, chronic SIV does not disturb the ability of TFH cells to help B cell maturation and production of SIV-specific immunoglobulins., Introduction The generation of antigen-specific B cells is dependent upon their interaction with T follicular helper (TFH) cells in the B cell follicles of the LN and spleen (SP) (1), [...]

This article proposes and investigates two asymmetric consequent-pole hybrid excited flux reversal machine (AS-CP-HEFRM) topologies, which have same numbers of iron poles and permanent magnets (PMs) with concentrated ac and dc windings on each stator pole and a salient pole rotor. If PM number on one stator pole is larger than 1, PMs are magnetized radially in the same direction on one stator pole, while opposite on adjacent stator poles. The phenomenon of the phase shift between the flux linkages of dc and PM excitations in the AS-CP-HEFRMs is revealed for the first time, which will weaken the regulation of dc excitation field to PM produced field. The elimination condition of the phase shift is derived and verified by finite-element analysis in this article, which can be considered as design guidelines in AS-CP-HEFRMs. Airgap magnetic field space harmonics of AS-CP-HEFRM are also investigated and verified by finite-element analyses. Meanwhile, the relationship between the rotor pole number and the stator pole arc (PM ratio) is derived and verified by global optimization based on genetic algorithm for maximum average torque. The influence of stator/rotor pole number combinations is also studied and compared in terms of torque, torque ripple, and flux regulation capability. The torque components produced by airgap magnetic field space harmonics are calculated and compared. A prototype has been built and tested to validate the finite element calculations. [ABSTRACT FROM AUTHOR]

A fast and low-complexity blind chromatic dispersion (CD) estimation method is proposed by a stepwise optimal order search of fractional Fourier transform (FrFT) in coherent optical communications. The method can track the cumulative dispersion over time in future dynamic and flexible scenarios. The validity of the FrFT method is verified by analogy to the field of CD estimation from the energy concentration property of the chirp signal, and the estimation equation of the CD value is obtained by parameter transformation. Numerical simulations have been carried out in the CD range of 1600 ps/nm to 32,000 ps/nm for 28 GBaud PM-QPSK and 14 GBaud PM-16QAM signals. The results show that the proposed algorithm achieves a high CD estimation accuracy with an average estimation error of less than 50 ps/nm within the 4096 sampling points and an order search interval of 0.0001. The effects of the polarization mode dispersion, optical signal-to-noise ratio and nonlinearity on CD estimation performance are discussed. In addition, the stepwise optimal order search method can achieve the purpose of greatly reducing the computational complexity under the premise of ensuring the accuracy of CD estimation. [ABSTRACT FROM AUTHOR]

The induced voltage ripple in DC field windings can cause many problems in hybrid excitation machines (HEMs). It can generate ripple current in field winding, thus causing unsteady magnetic field excitation and hence additional torque ripple and losses. Besides, the torque and power density of hybrid excitation machines may be deteriorated as a result of the influence of the induced voltage ripple on field winding's excitation circuit, particularly under high-speed conditions. Based on a hybrid excitation switched flux machine (HESFM), the influence of stator slot and rotor pole number combination on no-load and on-load field winding induced voltage ripples are studied and compared by the finite element method (FEM). It reveals that the harmonic content and thus the peak-to-peak value of the field winding induced voltage ripple are closely related to the stator slot and rotor pole number combination at both no-load and on-load operating conditions. The FEM calculations are verified by experiments on a prototype HESFM. [ABSTRACT FROM AUTHOR]

Abstract Background Graphics play an important and unique role in population pharmacokinetic (PopPK) model building by exploring hidden structure among data before modeling, evaluating model fit, and validating results after modeling. Results The work described in this paper is about a new R package called PKreport, which is able to generate a collection of plots and statistics for testing model assumptions, visualizing data and diagnosing models. The metric system is utilized as the currency for communicating between data sets and the package to generate special-purpose plots. It provides ways to match output from diverse software such as NONMEM, Monolix, R nlme package, etc. The package is implemented with S4 class hierarchy, and offers an efficient way to access the output from NONMEM 7. The final reports take advantage of the web browser as user interface to manage and visualize plots. Conclusions PKreport provides 1) a flexible and efficient R class to store and retrieve NONMEM 7 output, 2) automate plots for users to visualize data and models, 3) automatically generated R scripts that are used to create the plots; 4) an archive-oriented management tool for users to store, retrieve and modify figures, 5) high-quality graphs based on the R packages, lattice and ggplot2. The general architecture, running environment and statistical methods can be readily extended with R class hierarchy. PKreport is free to download at http://cran.r-project.org/web/packages/PKreport/index.html.

The dc winding induced voltage in hybrid-excited machines can lead to dc winding current ripple and hence, fluctuating field excitation. It may also challenge the dc power source and increase the difficulty of machine control, especially at high speed. The dc winding induced voltage in a hybrid-excited switched-flux permanent magnet (HESFPM) machine is investigated in this article. The phenomenon and mechanism of the dc winding induced voltages under both open-circuit and on-load conditions are analyzed, with particular emphasis on on-load operation which consists of open-circuit induced voltage and armature current induced voltage, respectively. Two techniques, i.e., rotor step skewing and unequal rotor teeth, are proposed and comparatively investigated by the finite-element (FE) method to suppress the dc winding induced voltage under on-load condition. FE results show that the peak-to-peak value of on-load dc winding induced voltage can be effectively suppressed by 96.15% or 89.05% by rotor step skewing or unequal rotor teeth, respectively, while the average on-load electromagnetic torque can be maintained at 89.4% or 87.8%. A prototype HESFPM machine is built and tested to verify the FE results. [ABSTRACT FROM AUTHOR]

Circular RNAs are widely existing in eukaryotes. However, there is as yet no tissue-specific Arabidopsis circular RNA database, which hinders the study of circular RNA in plants. Here, we used 622 Arabidopsis RNA sequencing data sets from 87 independent studies hosted at NCBI SRA and developed AtCircDB to systematically identify, store and retrieve circular RNAs. By analyzing back-splicing sites, we characterized 84 685 circular RNAs, 30 648 tissue-specific circular RNAs and 3486 microRNA–circular RNA interactions. In addition, we used a metric (detection score) to measure the detection ability of the circular RNAs using a big-data approach. By experimental validation, we demonstrate that this metric improves the accuracy of the detection algorithm. We also defined the regions hosting enriched circular RNAs as super circular RNA regions. The results suggest that these regions are highly related to alternative splicing and chloroplast. Finally, we developed a comprehensive tissue-specific database (AtCircDB) to help the community store, retrieve, visualize and download Arabidopsis circular RNAs. This database will greatly expand our understanding of circular RNAs and their related regulatory networks. AtCircDB is freely available at http://genome.sdau.edu.cn/circRNA. [ABSTRACT FROM AUTHOR]

Owing to the ferromagnetism and stray fields of inertial navigation system, component compensation of magnetic field distortion is significant for geomagnetic field vector measurement system. However, traditional scalar compensation methods cannot be used for component compensation of magnetic field distortion, so some improvement works have been researched for component compensation in the study, the major of which is estimating compensation parameters using the Lagrange multiplier method. Experiment results show that the performance of the component compensation method is much better than traditional scalar compensation method. After compensation, the maximal measurement errors of north, vertical, east components and total intensity caused by magnetic field distortion are reduced to 10.4 nT (0.91% of the raw error), 32.5 nT (5.20%), 12.9 nT (1.27%), and 18.4 nT (2.02%), respectively. In addition, compared with previous component compensation method, the proposed method has three advantages: (i) simplified equipment, (ii) easier operation process, and (iii) better generality. [ABSTRACT FROM AUTHOR]

A new regulatory class of small endogenous RNAs called circular RNAs (circRNAs) has been described as miRNA sponges in animals. Using 16 Arabidopsis thaliana RNA-Seq data sets, we identified 803 circRNAs in RNase R-/non-RNase R-treated samples. The results revealed the following features: Canonical and noncanonical splicing can generate circRNAs; chloroplasts are a hotspot for circRNA generation; furthermore, limited complementary sequences exist not only in introns, but also in the sequences flanking splice sites. The latter finding suggests that multiple combinations between complementary sequences may facilitate the formation of the circular structure. Our results contribute to a better understanding of this novel class of plant circRNAs. [ABSTRACT FROM AUTHOR]

The photovoltaic properties of nanoporous TiO2 films treated by different hydrochloric acid (HCl) concentrations were investigated in dye-sensitized solar cells (DSSCs). The nanostructure of the films was reformed, and the thickness decreased after the HCl hydrothermal treatment, which was observed by SEM analysis. It was found that the electron lifetime, band gap, recombination rate and TiO2 film electron injection efficiency had been changed by the processing when different analysis methods were employed to analyze the experimental results, including OCVD, UV-Vis and Mott–Schottky plots. In addition, the schematic for electron transfer and recombination was shown to discuss the process in clear detail. The performance of the DSSCs based on the different TiO2 films was measured by J–V curves and IPCE. When the TiO2 film was treated by 1 mol L−1 HCl at 180 °C for 3 h, the device had the optimum 7.77% photo-electric conversion performance and 16.04 mA cm−2Jsc. The results suggested that the reformed film nanostructure led to an optimized electron transportation pathway, and the decreased electron recombination and increased injection efficiency resulted in improved DSSCs. [ABSTRACT FROM AUTHOR]

Regulation of proteome diversity by alternative splicing has been widely demonstrated in plants and animals. NAGNAG splicing, which was recently defined as a tissue specific event, results in the production of two distinct isoforms that are distinguished by three nucleotides (NAG) as a consequence of the intron proximal or distal to the splice site. Since the NAGNAG mechanism is not well characterized, tools for the identification and quantification of NAGNAG splicing events remain under-developed. Here we report nagnag, an R-based NAGNAG splicing detection tool, which accurately identifies and quantifies NAGNAG splicing events using RNA-Seq. Overall, nagnag produces user-friendly visualization reports and highlights differences between the DNA/RNA/protein across the identified isoforms of the reported gene. The package is available on https://sourceforge.net/projects/nagnag/files/ ; or http://genome.sdau.edu.cn/research/software/nagnag.html . [ABSTRACT FROM AUTHOR]