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Existing literature reports the positive image impact of major sports events on sport tourists. This paper empirically tests the image impact of an overall sports events initiative on a host city, and on intention to revisit from the perspective of general international tourists. The findings show that major sports events, in general, can be useful in reaching out to tourists. However, it questions the utilisation of sports events in destination marketing to general tourists - as awareness of sports events actually depresses tourism atmosphere and service image, as well as the overall destination image. Practical implications and future research are suggested. [ABSTRACT FROM AUTHOR]

CeO2-coated SiO2 composite particles with Core-shell structure were successfully prepared, and the dispersion behavior in water was investigated under different pH values, ion-surfactant types and contents by means of Zeta potential and absorbance. Potential energy between particles in suspension was precisely evaluated via DLVO theory, by which the dispersion mechanism of SiO2/CeO2 core-shell composite particles was analyzed, combined with adsorption isotherms and infrared (IR) spectra measurements. The results showed that Zeta potential had a quite coherence with dispersion stability which was greatly affected by pH value, surfactant types and contents. The particles retained dispersion balance by adjusting pH value of suspension to increase electrostatic repulsion energy between particles, and the dispersion stability of suspension was preferable under pH value being 10 around. The adsorption of composite particles was physical adsorption, maximum amount of which reached 31.7 mg/g for CTAB and 19.23 mg/g for SDBS in certain range of concentration. The adding of surfactant SDBS proper dosage improved dispersion behavior greatly, and the adsorption layer of SDBS weakened the Van der Waals attractive energy dramatically and enhanced the absolute value of Zeta potential meanwhile, therefore, heightening of the electrostatic repulsion energy, then, leading to the improvement of dispersion stability of suspension. For the dispersion stability of suspension, SDBS was preferable to CTAB. [ABSTRACT FROM PUBLISHER]

By means of an iteration method and taking into account the broadening of the infrared pumping laser, the spectrum of a miniature, optically pumped, superradiant NH3 submillimeter-wave(SMMW) gas laser pumped by CO2-10R(8) has been calculated and studied by solving density matrix equations. Experimentally, the interferogram of miniature SMMW laser pumped by a TEA-CO2 laser with 10R(8) line is measured. This is the first time that the theoretical spectrum has been in good agreement with experimental results. [ABSTRACT FROM AUTHOR]

Seed laser pulses with average power of 146 μW and pulse duration of 480 fs were amplified to 14.5 mW. The pulse duration was compressed to 260 fs using 6 m high concentration E3+ r -doped fiber under forward pumping. The amplified signal pulse energy was 0.691 nJ (corresponding to a peak power of 2 657.7 W) and the repetition rate was 20.84 MHz. Spectrum breakup was observed simultaneously. The spectrum of pulses amplified by 3 m E3+ r -doped fiber remains a single peak under different pump power. The amplified pulse duration was compressed abnormally with the increasing pump power using the backward pumping; that is, the amplified pulses were compressed with the increasing pump power under low pump power. When the pump power reached 38 mW, the shortest amplified pulse duration was 309 fs. With further increase in pump power, the amplified pulses began broadening, accompanied by a single peak spectrum under different pump power. [ABSTRACT FROM AUTHOR]

The mechanism of femtosecond optical pulse generation in a self-starting Er3+-doped fiber ring soliton laser and experimental research results are discussed. Using the nonlinear polarization rotation effect of the fiber for sat-urable absorbers (and then self-amplitude modulation) which acts as the mode locking mechanism in an Er3+-doped fiber ring cavity laser, stable self-starting mode locking pulses have been generated. The shortest output pulse is 269 fs, with the central wavelength of 1,531 pm at the repetition rate of 21.37 MHz. The average output powen of the two terminators of the laser are 0.25 mW and 0.08 mW respectively. The threshold pump power which sustains the mode locking is 15 mW. Under high pump power, the laser works in a high order harmonic mode locking state. The mode locking pulse durations vs different cavity lengths are also studied. [ABSTRACT FROM AUTHOR]

We report on an all normal dispersion harmonically mode-locked ytterbium-doped femtosecond fiber laser. The mode-locking mechanism of the laser is based on nonlinear polarization evolution with strong pulse shaping. Bandpass filtering is achieved with a cascaded long-period fiber grating, forming highly chirped pulses. The laser generates stable 2.5-ps duration pulses at a repetition rate of 125.39 MHz that could be dechirped externally to 310 fs with a maximum pulse energy of 0.36 nJ. [ABSTRACT FROM PUBLISHER]

Rapeseed–rice rotation is a cropping system that improves the land-use rate. The present study conducted a field experiment with winter planting of rapeseed as treatment (WR) and winter fallow as control (CK) to investigate the effects of winter planting of rapeseed on growth, yield formation, and 2-acetyl-1-pyrroline (2-AP) biosynthesis of fragrant rice in the two subsequent cropping seasons. The results show that WR treatment improved alkali-hydro nitrogen and rapidly available phosphorus contents in soil. Compared with CK, WR treatment significantly increased grain yield and effective panicle number per plant by 21.16–27.26% and 7.33–21.24%, respectively. Higher net photosynthetic rate, leaf area index, and dry matter accumulation of fragrant rice plants were recorded in WR treatment and CK. Furthermore, compared with CK, WR treatment significantly increased grain 2-AP content, which could be explained by increased content of pyrroline-5-carboxylic acid, methylglyoxal, 1-pyrroline, and enhanced activity of proline dehydrogenase. In addition, future studies should be conducted at a molecular level to reveal the regulation mechanism in 2-AP biosynthesis of fragrant rice under conditions of winter planting of rapeseed. [ABSTRACT FROM AUTHOR]

• By combining automatic image acquisition-transmission system, the image segmentation model trained on U 2− net , and an improved structure from motion algorithm (IVOP & AKAZE-SFM), a 3D reconstruction method is proposed for obtaining high-precision point cloud of complex plant automatically. • A scale restoration method including color filtering, Euclidean clustering, and a size calibration algorithm based on prior information is proposed to obtain a clean and proportional point cloud of complex plant. • A plant phenotyping platform based on the multi-view images to reconstruct high-precision and proportional point clouds for complex plants is constructed, which integrates hardware components such as the Raspberry Pi camera and motorized turntable, as well as algorithms for image acquisition, image segmentation, 3D reconstruction, and point cloud processing. Three-dimensional reconstruction plays a crucial role in quantifying crop phenotypes and exploring crop physiological structures. This paper presents a phenotyping platform designed for the 3D reconstruction of complex plants, utilizing multi-view images and introducing a joint evaluation criterion for both the reconstruction algorithm and the platform. Initially, a device composed of Raspberry Pi camera, SSH protocol, USB-TTL, motorized turntable, and shadow booth is built for automated image acquisition and transmission. Then, a dataset containing carex cabbage and kale is created and trained based on U 2 - n e t to achieve precise image segmentation. After that, an improved structure from motion algorithm, named IVOP & AKAZE-SFM, and multi-view stereo algorithm are utilized for the fine-scale reconstruction of plants. Next, by combing color filtering and Euclidean clustering, a denoising algorithm is proposed to obtain clean point clouds of plants. Finally, a method for calibrating the size of the plant point cloud based on priori condition is proposed to solve the problem of point cloud deformation in reconstruction. The evaluation of image segmentation model resulted in a precision of 0.91, a recall of 0.972, an IOU of 0.943, and a max F β of 0.099. The proposed IVOP&AKAZE-SFM is assessed against mainstream algorithms, the results show that our algorithm has the minimum average track length, minimum average reprojection error and generated the most points. The correlation coefficient (R 2) between the extracted traits and measured phenotype, such as plant height and plant width, are 0.999 and 1.000, while the root means squared errors (RMSE) are 0.298 cm and 0.338 cm. Consequently, the platform offers a cost-effective, automated, and integrated solution for fine-scale plant 3D reconstruction. [ABSTRACT FROM AUTHOR]

Treatment of Parkinson's disease with levodopa/carbidopa/entacapone (LCE) has been studied for a long time. However, the efficacy and safety of LCE in the treatment of early Parkinson's disease (PD) still need to be assessed. Our objective was to do a meta-analysis of relevant randomized controlled trials (RCTs) to evaluate the efficacy and safety of LCE for early PD. PubMed, Embase, the Cochrane Library, and the Web of Science were searched for RCTs with "levodopa/carbidopa/entacapone" and "Parkinson's disease" as keywords. The search period was from inception to October 2018. The quality of included studies was strictly evaluated. We evaluated the quality of included studies strictly and six studies met all inclusion criteria. The results showed that LCE could improve activities of daily living and motor function in PD patients. However, LCE therapy was associated with higher risks of total AEs and single AEs compared with traditional therapy. [ABSTRACT FROM AUTHOR]

The morphological characteristics of rock joints have a significant impact on the peak shear strength of a rock mass. In this study, three-dimensional scanning tests have been conducted on 39 joint specimens. Based on the scanning data, the morphological parameter C′ has been developed to describe the joint roughness. With an explicit physical meaning, this index is negatively correlated with the joint roughness and can reflect the anisotropy of surface morphology. Using a newly developed derivation method, the morphological parameter C′ of each joint from the earlier studies has been determined. The scanning test results in this study have been used to confirm the feasibility of this new derivation method. By applying the least square fitting method to the Grasselli’s (Shear strength of rock joints based on quantified surface description. Dissertation, Swiss Federal Institute of Technology, 2001) test results, a new peak shear strength model has been developed. Finally, a comparison of the peak shear strength of rock joint predicted by the new model and other classic models shows that the new model, characterized by simplicity, relatively higher precision, and a definite physical meaning, is feasible to predict the peak shear strength of rock joints. [ABSTRACT FROM AUTHOR]

Streaming transports of the two-dimensional electron gas (2DEG) in AlGaN/GaN/AlGaN double heterostructures (DHs) are investigated by using the ensemble Monte Carlo simulation method. The dependence of streaming transport on basic parameters of DHs, such as Al composition, GaN channel width, interface roughness, and temperature, is obtained. It is demonstrated that streaming transports of 2DEG in DHs only can be realized by careful choice of those basic parameters and the externally applied electric field parallel to the interface. Weak alloy disorder (ADO) and interface roughness (IFR) scatterings, which can be obtained by using low Al compositions and wide GaN channels, are of benefit to streaming transport in DHs. On the other hand, it is found that dislocation scattering does not play an obvious influence on the transient drift velocity, compared to ADO and IFR scatterings. [ABSTRACT FROM AUTHOR]

The surface morphology of joints has a significant effect on the mechanical properties of rock masses. The key morphological indices developed in this study have been used to analyze the joint surface morphology quantitatively, and a new peak shear strength model has also been developed. Firstly, three-dimensional morphology scanning tests have been carried out on seven groups (27 blocks in total) of rock joints with different surface morphologies, and a new functional relationship between the apparent dip angle and the initial contact area ratio has been established: i.e. A θ ∗ + = exp − θ ∗ / θ ¯ ∗ n , where A θ ∗ + is the contact area ratio, θ ¯ ∗ is the characteristics angle, and n is a fitting parameter. The average joint height has been used to account for the effect of the joint fluctuation on the surface morphology. Ten standard roughness profiles have been digitalized to compute the roughness indices of each profile and to establish a relationship with the JRC (joint roughness coefficient). The direct shear tests have been carried out. By analyzing the test results, a new peak shear strength model has been developed. Comparing with the results from five classical models, the error between the calculated results of the new model and the experimental results is the smallest. Hence, the new model is a reliable tool for the estimation of the peak shear strength of rock joints. [ABSTRACT FROM AUTHOR]

Background: Hexaploid bread wheat (Triticum aestivum L) arose by two polyploidisation events from three diploid species with homoeologous genomes. Nullisomic-tetrasomic (nulli-tetra or NT) lines are aneuploid wheat plants lacking two and adding two of six homoeologous chromosomes. These plants can grow normally, but with significantly morphological variations because the adding two chromosomes or the remaining four chromosomes compensate for those absent. Despite these interesting phenomena, detailed molecular mechanisms underlying dosage deletion and compensation in these useful genetic materials have not been determined. Results: By sequencing the transcriptomes of leaves in two-week-old seedlings, we showed that the profiles of differentially expressed genes between NT stocks for homoeologous group 7 and the parent hexaploid Chinese Spring (CS) occurred throughout the whole genome with a subgenome and chromosome preference. The deletion effect of nulli-chromosomes was compensated partly by the tetra-chromosomes via the dose level of expressed genes, according to the types of homoeologous genes. The functions of differentially regulated genes primarily focused on carbon metabolic process, photosynthesis process, hormone metabolism, and responding to stimulus, and etc., which might be related to the defective phenotypes that included reductions in plant height, flag leaf length, spikelet number, and kernels per spike. Conclusions: The perturbation of the expression levels of transcriptional genes among the NT stocks for homoeologous group 7 demonstrated the gene dosage effect of the subgenome at the genome-wide level. The gene dosage deletion and compensation can be used as a model to elucidate the functions of the subgenomes in modern polyploid plants. [ABSTRACT FROM AUTHOR]

In this paper, the energy levels and the wave functions of the schrödinger equation with position-dependent mass (PDM) are theoretically deduced, and they are brought into the nonlinear optical rectification (OR) and the second harmonic generation (SHG). We find that the peaks of coefficient curves of optical rectification and second harmonic generation become larger and occur blue shift under the condition of variable mass. Moreover, with the increment of mass variable k , the energy interval E i j decreases, which makes the coefficients suffer a red shift, and the absolute value of the matrix elements product | M i j M j k M k i | presents different monotonicity, that makes the peaks value of coefficients change regularly. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three probiotics were combined to ferment blueberry juice. • Regrssion modeling and genetic algorithm were used to optimize inoculation proportion. • The combined L. plantarum and L. fermentum at 0.5:0.5 enriched phenolics best. • Mixed fermented juices had highest rutin and quercetin-3-rhamnoside contents. • Mixed fermentation produced more alcohols and ketones than L. fermentum fermentation. Three strains, including L. fermentum , L. plantarum and S. thermophilus, were combined to ferment blueberry juice. Through the sequential simplex lattice mixture design, regression modeling and genetic algorithm optimization, it was found that the combination of S. thermophilus with either L. fermentum or L. plantarum weakened the capacity of Lactobacillus strains to enrich phenolics, and the combinations of these strains had no synergistic effect of synthesizing lactic acid. The resulting optimal inoculation proportion to enrich phenolics was the mixed L. fermentum and L. plantarum at 0.5:0.5. After fermentation for 48 h, total phenolic, ferulic acid, rutin, and quercetin-3-rhamnoside of mixed fermented samples were 82.19 %, 15.22 %, 79.08 % and 98.59 % higher than the unfermented juice, and their contents were all highest among the fermented samples. Moreover, the samples fermented by mixed strains possessed higher amounts of 3-methyl-1-butanol, 2-methyl-1-propanol, 2-heptanone and 2-pentanone than samples fermented by L. fermentum , S. thermophilus and unfermented samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • The components and factors in the metabolic pathways of glucoraphanin were analyzed. • Melatonin or vitamin C pretreatments protected broccoli sulforaphane during drying. • The exogenous pretreatments also protected broccoli myrosinase during drying. • Contact sonication during drying promoted the degradation of glucoraphanin. In this investigation, the combinations of exogenous pretreatment (melatonin or vitamin C) and contact ultrasound-assisted air drying were utilized to dry broccoli florets. To understand the influences of the studied dehydration methods on the conversion of glucoraphanin to bioactive sulforaphane in broccoli, various components (like glucoraphanin, sulforaphane, myrosinase, etc.) and factors (temperature and moisture) involved in the metabolism pathway were analyzed. The results showed that compared with direct air drying, the sequential exogenous pretreatment and contact ultrasound drying shortened the drying time by 19.0–22.7%. Meanwhile, contact sonication could promote the degradation of glucoraphanin. Both melatonin pretreatment and vitamin C pretreatment showed protective effects on the sulforaphane content and myrosinase activity during the subsequent drying process. At the end of drying, the sulforaphane content in samples dehydrated by the sequential melatonin (or vitamin C) pretreatment and ultrasound-intensified drying was 14.4% (or 26.5%) higher than only air-dried samples. The correlation analysis revealed that the exogenous pretreatment or ultrasound could affect the enzymatic degradation of glucoraphanin and the generation of sulforaphane through weakening the connections of sulforaphane-myrosinase, sulforaphane-VC, and VC-myrosinase. Overall, the reported results can enrich the biochemistry knowledge about the transformation of glucoraphanin to sulforaphane in cruciferous vegetables during drying, and the combined VC/melatonin pretreatment and ultrasound drying is conducive to protect bioactive sulforaphane in dehydrated broccoli. [ABSTRACT FROM AUTHOR]

Pretreatments of either water blanching or NaCl immersion and airborne ultrasound-assisted air drying were combined to dehydrate apple slices. The drying time was found to be reduced by 1.6–69.0% compared with air drying without any pretreatment and sonication. Meanwhile, it was found that sequential water blanching coupled with air drying with sonication gave the shortest drying time. A modified diffusional model incorporating temperature-dependent moisture diffusivity (D eff) could simulate the apple drying process well. Water blanching pretreatment and airborne sonication were found to lower the activation energy required for the enhancement of moisture diffusive ability, and intensify water exchange on apple surface to speed up the drying process. Both water blanching and NaCl immersion significantly increased the amounts of procyanidin B2 in dehydrated apple slices. However, airborne sonication promoted the loss of procyanidin B2 in apple slices with pretreatments during air drying. In addition, sonication had no obvious influences on apple PPO activity and individual organic acids throughout drying. Overall, the sequential NaCl immersion pretreatment (or water blanching pretreatment) and drying with airborne sonication are effective to improve the quality of dried apple slices. [Display omitted] • Pretreatments and air drying with sonication reduced apple drying time by 1.5–68.9%. • A modified diffusional model with temperature factor predicted apple drying well. • Water blanching and NaCl immersion enhanced procyanidin B2 content of dehydrated apple. • Sonication promoted the loss of procyanidin B2 in apple samples with pretreatments. • Organic acid profile and PPO activity were less affected by ultrasound-assisted drying. [ABSTRACT FROM AUTHOR]

The chilling stress induced by the global climate change harms rice production, especially at seedling and booting stage, which feed half the population of the world. Although there are key quantitative trait locus genes identified in the individual stage, few genes have been reported and functioned at both stages. Utilizing chromosome segment substitution lines (CSSLs) and a combination of map-based cloning and phenotypes of the mutants and overexpression lines, we identified the major gene Chilling-tolerance in Geng/japonica rice 3 (COG3) of q chilling-tolerance at the booting and seedling stage 11 (qCTBS11) conferred chilling tolerance at both seedling and booting stages. COG3 was significantly upregulated in Nipponbare under chilling treatment compared with its expression in 93-11. The loss-of-function mutants cog3 showed a reduced chilling tolerance. On the contrary, overexpression enhanced chilling tolerance. Genome evolution and genetic analysis suggested that COG3 may have undergone strong selection in temperate japonica during domestication. COG3, a putative calmodulin-binding protein, physically interacted with OsFtsH2 at chloroplast. In cog3-1, OsFtsH2-mediated D1 degradation was impaired under chilling treatment compared with wild-type. Our results suggest that COG3 is necessary for maintaining OsFtsH2 protease activity to regulate chilling tolerance at the booting and seedling stage., (© 2024 The Authors. New Phytologist © 2024 New Phytologist Foundation.)

Background: The P-stalk is a conserved and vital structural element of ribosome. The eukaryotic P-stalk exists as a P0-(P1-P2) 2 pentameric complex, in which P0 function as a base structure for incorporating the stalk onto 60S pre-ribosome. Prior studies have suggested that P0 genes are indispensable for survival in yeast and animals. However, the functions of P0 genes in plants remain elusive., Results: In the present study, we show that rice has three P0 genes predicted to encode highly conserved proteins OsP0A, OsP0B and OsP0C. All of these P0 proteins were localized both in cytoplasm and nucleus, and all interacted with OsP1. Intriguingly, the transcripts of OsP0A presented more than 90% of the total P0 transcripts. Moreover, knockout of OsP0A led to embryo lethality, while single or double knockout of OsP0B and OsP0C did not show any visible defects in rice. The genomic DNA of OsP0A could well complement the lethal phenotypes of osp0a mutant. Finally, sequence and syntenic analyses revealed that OsP0C evolved from OsP0A, and that duplication of genomic fragment harboring OsP0C further gave birth to OsP0B, and both of these duplication events might happen prior to the differentiation of indica and japonica subspecies in rice ancestor., Conclusion: These data suggested that OsP0A functions as the predominant P0 gene, playing an essential role in embryo development in rice. Our findings highlighted the importance of P0 genes in plant development., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Fertilizer management can influence soil microbes, soil properties, enzymatic activities, abundance and community structure. However, information on the effects of biochar in combination with organic-inorganic fertilizer after 3 years under pomelo orchard on soil bacterial abundance, soil properties and enzyme activities are not clear. Therefore, we conducted a field experiment with seven treatments, i.e., (1) Ck (control), (2) T1 (2 kg biochar plant -1 ), (3) T2 (4 kg biochar plant -1 ), (4) T3 (2 kg organic-inorganic mixed fertilizer plant -1 ), (5) T4 (4 kg biochar + 1.7 kg organic-inorganic mixed fertilizer plant -1 ), (6) T5 (4 kg biochar + 1.4 kg organic-inorganic mixed fertilizer plant -1 ), and (7) T6 (4 kg biochar + 1.1 kg organic-inorganic mixed fertilizer plant -1 ). The soil microbial communities were characterized using high-throughput sequencing of 16S and internal transcribed spacer (ITS) ribosomal RNA gene amplicons. The results showed that biochar combined with organic-organic fertilizer significantly improved soil properties (pH, alkali hydrolysable nitrogen, available phosphorus, available potassium, and available magnesium) and soil enzymatic activities [urease, dehydrogenase (DHO), invertase and nitrate reductase (NR) activities]. Furthermore, soil bacterial relative abundance was higher in biochar and organic-inorganic treatments as compared to control plots and the most abundant phyla were Acidobacteria (40%), Proteobacteria (21%), Chloroflexi (17%), Planctomycetes (8%), Bacteroidetes (4%), Verrucomicrobia (2%), and Gemmatimonadetes (1%) among others. Among the treatments, Acidothermus, Acidibacter , Candidatus Solibacter and F473 bacterial genera were highest in combined biochar and organic-inorganic treatments. The lowest bacterial abundance and bacterial compositions were recorded in control plots. The correlation analysis showed that soil attributes, including soil enzymes, were positively correlated with Chloroflexi, Planctomycetes, verrucomicrobia, GAL15 and WPS-2 bacterial abundance. This study demonstrated that biochar with organic-inorganic fertilizer improves soil nutrients, enzymatic activities and bacterial abundance., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Song, Zhao, Guo, Ali, Li, Lin and Liu.)

Citrate salts (CSs), as one type of organic salts, have been widely used in the food and pharmaceutical industries. Accurate and quantitative detection of CSs in food and medicine is very important for health and safety. In this study, an asymmetric double-opening ring metamaterial sensor is designed, fabricated, and used to detect citrate salts combined with THz spectroscopy. Factors that influence the sensitivity of the metamaterial sensor including the opening positions and the arrangement of the metal opening ring unit, the refraction index and the thickness of the analyte deposited on the metamaterial sensor were analyzed and discussed from electromagnetic simulations and THz spectroscopy measurements. Based on the high sensitivity of the metamaterial sensor to the refractive index of the analyte, six different citrate salt solutions with low concentrations were well identified. Therefore, THz spectroscopy combined with a metamaterials sensor can provide a new, rapid, and accurate detection of citrate salts.

Using Shanghai Tennis Masters as an example, this study seeks to explore the psychic income associated with major sports events hosting and whether the psychic income would predict the attitudes of local residents toward events hosting. In addition, the moderating effect of sport involvement on the relationship between psychic income and attitude is also tested. In this study, a questionnaire survey is adopted. The structured questionnaire was developed based on 4 parts, including the demographics of the residents, involvement in the sport event, psychic income from the sport event, and their attitudes toward the sports event, there were 47 items in total. Data were collected from the local residents of Shanghai (including 16 districts or counties), as a result, 1,302 valid questionnaires were collected. A series of statistical analyses were conducted by using SPSS25.0 and AMOS 24.0 to examine the reliability and validity of the scales and to test the hypotheses. The results showed that the event has brought a significant level of psychic income to the local community, and the perceived psychic income would predict the attitudes of the residents toward the event hosting. The moderating effect of sports involvement on the relationship between psychic income and attitude is also confirmed., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zhang, Liu, Plumley and Chai.)

The bacterium Xanthomonas oryzae pv. Oryzae (Xoo) causes blight in rice worldwide, resulting in significant crop loss. However, no gene underlying a quantitative trait locus (QTL) for resistance against Xoo has been cloned yet. Here, we report the map-based cloning of a QTL, in which the NBS8R gene confers quantitative resistance to Xoo. NBS8R encodes an NB-ARC protein, which is involved in pathogen/microbe-associated molecular pattern-triggered immunity and whose expression is regulated by non-TAL effector XopQ-inducible Osa-miR1876 through DNA methylation. Sequence analysis of NBS8R in wild rice species and rice cultivars suggests that the Osa-miR1876 binding sites in the 5' UTR of NBS8R are inserted by chance and have undergone variations with Osa-miR1876 throughout evolution. The interaction between NBS8R and XopQ-inducible Osa-miR1876 is partially in keeping with the zigzag model, revealing that quantitative genes may also follow this model to control the innate immune response or basal disease resistance, and may prove valuable in utilizing the existing landraces that harbor the NBS8R gene but with no Osa-miR1876 binding site in rice breeding for bacterial blight resistance., (Copyright © 2020 The Author. Published by Elsevier Inc. All rights reserved.)

MicroRNAs (miRNAs) are crucial player in plant-pathogen interaction. While the evidence has demonstrated that rice miRNAs mediate immune response to pathogens invasion, the roles of miRNAs on Xanthomonas oryzae pv. oryzae ( Xoo ) attack remain be in place. Herein, we monitored the responsive changes of rice miRNAs at 0, 8, 24 h across Xoo strain PXO86 infection in its compatible rice variety IR24 and incompatible variety IRBB5 by small RNA sequencing, and the genes targeted by miRNAs were also detected via degradome technology. The faithfulness of sequencing data was validated through quantitative real-time stem-loop reverse transcription-polymerase chain reaction assay. Bioinformatic analysis showed that the differentially expressed miRNAs could be divided into three immunity-related clusters, and 80 regulatory units were emerged in infection process, which comprises 29 differentially expressed known miRNAs and 38 cleaved targets. Furthermore, the miRNA presumptive function of separate immunity cluster in rice-Xoo interplay was confirmed through overexpressing osa-miR164a, osa-miR167d and osa-miR159b, and the disruption of regulatory units, osa-miR164a/ OsNAC60, osa-miR167d-5p/ OsWD40-174 and osa-miR159b/ OsMYBGA , OsLRR-RLK2 , OsMPK20-4 , may reset rice defense response to Xoo infestation in a controllable manner . These findings provide new insights into the complex roles of characteristic miRNAs and their targets in rice- Xoo interactions., Competing Interests: The authors declare that they have no competing interests.

A pollen defective male sterile rice mutant, osms55, was isolated from an elite indica cultivar HHZ using EMS (ethyl methanesulfonate) mutagenesis strategy. Genetic analysis showed that osms55 was controlled by a single recessive gene. Genome-wide SNP analysis using the high-throughput Illumina Infinium iSelect SNP (50 K) microarray technology indicated that the genetic makeup of osms55 is the same as wild type (WT) HHZ. Using a modified MutMap method, we successfully identified a mutation in the LOC_Os02g40450 (MER3) gene that is co-segregated with the male sterility phenotype. The mutation is located at the intron splice-recognition site, leading to a 15 nucleotide deletion in the fifth exon. Different from the published MutMap method that aligns the mutant pool DNA sequence with the assembled WT genome, the method used in this study was to align the re-sequencing data of the mutant pool DNA and WT HHZ with the Nipponbare reference genome. The resulting SNPs of mutant/Nipponbare and WT HHZ/Nipponbare were further compared to determine the candidate mutant gene. This modified method does not need an assembled WT genome as reference and thus is more cost-effective and widely applicable.

The highly conserved florigen gene FLOWERING LOCUS T (FT) functions at the core of the flowering pathways. Extensive studies have examined the transcriptional regulation of FT; however, other layers of FT regulation remain unclear. Here, we identified miR5200 a Pooideae-specific microRNA that is expressed in leaves and targets Brachypodium distachyon FT orthologs for mRNA cleavage. miR5200 was abundantly expressed in plants grown under short-day (SD) conditions but was dramatically repressed in plants transferred to long-day (LD) conditions. We also found that the epigenetic chromatin status, specifically the levels of histone methylation marks, at miR5200 precursor loci changed in response to daylength. Moreover, artificial interruption of miR5200 activity by target mimicry in B. distachyon altered flowering time in SD but not in LD conditions, suggesting that miR5200 functions in photoperiod-mediated flowering time regulation. Together, these findings illustrate a posttranscriptional regulation mechanism of FT and provide insights into understanding of the multiple concerted pathways for flowering time control in plants.

Rice OsERF922, encoding an APETELA2/ethylene response factor (AP2/ERF) type transcription factor, is rapidly and strongly induced by abscisic acid (ABA) and salt treatments, as well as by both virulent and avirulent pathovars of Magnaporthe oryzae, the causal agent of rice blast disease. OsERF922 is localized to the nucleus, binds specifically to the GCC box sequence, and acts as a transcriptional activator in plant cells. Knockdown of OsERF922 by means of RNAi enhanced resistance against M. oryzae. The elevated disease resistance of the RNAi plants was associated with increased expression of PR, PAL, and the other genes encoding phytoalexin biosynthetic enzymes and without M. oryzae infection. In contrast, OsERF922-overexpressing plants showed reduced expression of these defence-related genes and enhanced susceptibility to M. oryzae. In addition, the OsERF922-overexpressing lines exhibited decreased tolerance to salt stress with an increased Na(+)/K(+) ratio in the shoots. The ABA levels were found increased in the overexpressing lines and decreased in the RNAi plants. Expression of the ABA biosynthesis-related genes, 9-cis-epoxycarotenoid dioxygenase (NCED) 3 and 4, was upregulated in the OsERF922-overexpressing plants, and NCED4 was downregulated in the RNAi lines. These results suggest that OsERF922 is integrated into the cross-talk between biotic and abiotic stress-signalling networks perhaps through modulation of the ABA levels.

We report an all-normal-dispersion, low-repetition-rate, high-energy, twin-pulse, passively mode locked ytterbium-doped fiber laser. The mode-locking mechanism of the laser is based on nonlinear polarization evolution and strong pulse shaping with a cascade long-period fiber grating bandpass filtering in a highly chirped pulse. The laser generates a highly stable twin-pulse group with 248 ps and 296 ps duration simultaneously and maximum pulse energy of 26.8 nJ-each pulse at a 2.5445 MHz repetition rate. Energy quantization is observed, which demonstrates the nonparabolic nature of these pulses. The laser can also work in third-harmonic mode locking with 17.8 nJ energy (at a repetition rate of 7.65 MHz and pulse width of 780 ps).