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Welan gum (WG) has a wide range of applications, but it is not yet suitable for applications such as oil recovery profile control that have complex requirements for viscosity, gelation properties, and so forth. Grafting modification is an important strategy for improving the property of WG, but there are few reports on controllable modification of WG to customize it for specific application. Acrylamide (AM) dosage was identified as the key factor affecting the grafting ratio of AM onto WG by a uniform experimental design. The grafting ratio can be directly adjusted between 99% and 378% based on the positive correlation with dosage of AM, and viscosity can be adjusted between 206 and 327 mPa s based on the negative correlation with grafting ratio. The 50% weight loss temperature of W11 with a grafting ratio of 110% raised from 314 to 336°C after grafting. The viscosity of the hydrogel formed with WG11 reached 15,654 mPa s, nearly nine times higher than that of unmodified WG. In addition, the gelation time can be controlled within 5 days, so that it can be injected to the optimal area in oilfield profile, avoiding pipeline blockage. This study enables adjusting viscosity of WG grafted with AM by controlling the grafting rate, and enhances gelation performance and thermal stability of WG, which will expand the application of WG in oil recovery and other fields.
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Group 1 innate lymphoid cells (ILCs) comprise conventional natural killer (cNK) cells and type 1 innate lymphoid cells (ILC1s). The main functions of liver cNK cells and ILC1s not only include directly killing target cells but also regulating local immune microenvironment of the liver through the secretion of cytokines. Uncovering the intricate mechanisms by which transcriptional factors regulate and influence the functions of liver cNK cells and ILC1s, particularly within the context of liver tumors, presents a significant opportunity to amplify the effectiveness of immunotherapies against liver malignancies. Using Ncr1-drived conditional knockout mouse model, our study reveals the regulatory role of Prdm1 in shaping the composition and maturation of cNK cells. Although Prdm1 did not affect the killing function of cNK cells in an in vivo cytotoxicity model, a significant increase in cancer metastasis was observed in Prdm1 knockout mice. Interferon-gamma (IFN-γ), granzyme B, and perforin secretion decreased significantly in Prdm1-deficient cNK cells and liver ILC1s. Single-cell RNA sequencing (scRNA-seq) data also provided evidences that Prdm1 maintains functional subsets of cNK cells and liver ILC1s and facilitates communications between cNK cells, liver ILC1s, and macrophages. The present study unveiled a novel regulatory mechanism of Prdm1 in cNK cells and liver ILC1s, showing promising potential for developing innovative immune therapy strategies against liver cancer.
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Neoplasias Hepáticas , Camundongos Knockout , Fator 1 de Ligação ao Domínio I Regulador Positivo , Animais , Camundongos , Fator 1 de Ligação ao Domínio I Regulador Positivo/genética , Fator 1 de Ligação ao Domínio I Regulador Positivo/metabolismo , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/genética , Células Matadoras Naturais/imunologia , Interferon gama/metabolismo , Imunidade Inata , Linfócitos/imunologia , Vigilância Imunológica , Granzimas/metabolismo , Granzimas/genética , Receptor 1 Desencadeador da Citotoxicidade Natural/metabolismo , Receptor 1 Desencadeador da Citotoxicidade Natural/genética , Perforina/metabolismo , Perforina/genética , Fígado/imunologia , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Microambiente Tumoral/imunologia , Antígenos LyRESUMO
AIM: Biotechnical processes in Escherichia coli often operate with artificial plasmids. However, these bioprocesses frequently encounter plasmid loss. To ensure stable expression of heterologous genes in E. coli BL21(DE3), a novel plasmid addiction system (PAS) was developed. METHODS AND RESULTS: This PAS employed an essential gene grpE encoding a cochaperone in the DnaK-DnaJ-GrpE chaperone system as the selection marker, which represented a chromosomal ΔgrpE mutant harboring episomal expression plasmids that carry supplementary grpE alleles to restore the deficiency. To demonstrate the feasibility of this system, it was implemented in phloroglucinol (PG) biosynthesis, manifesting improved host tolerance to PG and increased PG production. Specifically, PG titer significantly improved from 0.78 ± 0.02 to 1.34 ± 0.04 g l-1, representing a 71.8% increase in shake-flask fermentation. In fed-batch fermentation, the titer increased from 3.71 ± 0.11 to 4.54 ± 0.10 g l-1, showing a 22.4% increase. RNA sequencing and transcriptome analysis revealed that the improvements were attributed to grpE overexpression and upregulation of various protective chaperones and the biotin acetyl-CoA carboxylase ligase coding gene birA. CONCLUSION: This novel PAS could be regarded as a typical example of nonanabolite- and nonmetabolite-related PAS. It effectively promoted plasmid maintenance in the host, improved tolerance to PG, and increased the titer of this compound.
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Proteínas de Escherichia coli , Proteínas de Choque Térmico , Floroglucinol , Plasmídeos , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Fermentação , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Floroglucinol/metabolismo , Floroglucinol/análogos & derivados , Plasmídeos/genéticaRESUMO
Graft copolymerization is an effective approach to improve performance of polysaccharide. However, selecting the most suitable modification strategy can be challenging due to the intricate molecular structure. Rational design through computer aided molecular dynamics (MD) simulations requires substantial computational resources. This study designed a simplified MD simulation strategy and suggested that grafting acrylamide (AM) could effectively adjust the molecular conformation of xanthan gum (XG) and its derivatives, thus regulating its viscosity and gelation properties. To rationally modify XG, a uniform experimental design was applied to tune the grafting ratios ranging from 72 % to 360 %, resulting in XG-AM solutions with viscosity ranging from 9 to 104 mPaâ¢s at a concentration of 0.3 %. XG-AM was crosslinked by acid phenolic resin to generate gel with the viscosity of 7890 mPa·s in 3 days, which was 13 times the viscosity of unmodified XG. The controllable gelation will enhance the efficacy of XG-AM in oil recovery. By integrating rational selection of grafting strategies based on simplified MD simulation of polysaccharide derivatives and controllable grafting modification with specified grafting rates, customized production of polysaccharide derivatives can meet the requirements of a diverse range of applications.
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Simulação de Dinâmica Molecular , Polissacarídeos Bacterianos , Polissacarídeos Bacterianos/química , Viscosidade , Acrilamida/química , PolimerizaçãoRESUMO
To realize the high sensitivity polarization sensitive optical coherence tomography (PS-OCT) imaging, a fiber-based full-range depth-encoded swept source PS-OCT (SS-PS-OCT) method is proposed. The two OCT images corresponding to the orthogonal polarized input light are located on the high sensitivity imaging region of the opposite sides relative to the zero optical path difference position. The full-range OCT images can be obtained by implementing the spatial phase modulation in the reference arm. The detection sensitivity of the system was measured experimentally to be 67â dB when the imaging depth approaching to 2 mm. The imaging of the biological tissue verifies that the proposed full-range depth-encoded SS-PS-OCT system has the higher detection sensitivity compared with the conventional depth encoded SS-PS-OCT system. Finally, we demonstrated the full-range high sensitivity phase retardation image of the bovine tendon and skin of human fingertip. The fiber-based full-range depth-encoded SS-PS-OCT method can realize the high sensitivity birefringence imaging in the medical diagnosis scenes with the requirements for long imaging range and high detection sensitivity.
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As an intrinsically direct current device, quantum-dot LED cannot be directly driven by household alternating current electricity. Thus, a driver circuit is required, which increases the complexity and cost. Here, by using a transparent and conductive indium-zinc-oxide as an intermediate electrode, we develop a tandem quantum-dot LED that can be operated at both negative and positive alternating current cycles with an external quantum efficiency of 20.09% and 21.15%, respectively. Furthermore, by connecting multiple tandem devices in series, the panel can be directly driven by household alternating current electricity without the need for complicated back-end circuits. Under 220 V/50 Hz driving, the red plug-and-play panel demonstrates a power efficiency of 15.70 lm W-1 and a tunable brightness of up to 25,834 cd m-2. The developed plug-and-play quantum-dot LED panel could enable the production of cost-effective, compact, efficient, and stable solid-state light sources that can be directly powered by household alternating current electricity.
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Totally extraperitoneal prosthetic (TEP) is a surgical technique for the treatment of hernia. The purpose of this research is to compare the efficacy of both general anaesthesia and spine anaesthesia for TEP herniorrhaphy. The number of patients who received TEP operations related to the injury from 2008 to 2022 was counted in this study. Patients with TEP operation were classified into general anaesthesia and spine anaesthesia. In this research, 186 related articles were found in the data base, and in the end, 8 were analysed. This study involved 2452 cases of hernia. The data of the operation time, the infection of the wound and the bleeding of the wound were analysed. The analysis of the data was done with RevMan 5.3. Results indicated that there was no significant difference between general anaesthesia and spinal anaesthesia in post-surgical rates for post-operative wound infection (odds ratio [OR], 0.94; 95% confidence interval [CI], 0.49-1.83; p = 0.86); In general anaesthesia, there was no difference in the risk of post-operative wound haematoma when compared with those treated with spinal anaesthesia (OR, 2.96; 95% CI, 0.37-23.69; p = 0.31). In the seven trials, there was no difference in the duration of the surgery between the general anaesthetic and the spinal anaesthesia group (mean difference, -1.44; 95% CI, -4.11 to 1.22; p = 0.29). Data from the available meta-analysis indicate that there is no difference in the risk of post-operative wound infection or wound haematoma when treated with TEP.
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Raquianestesia , Hérnia Inguinal , Laparoscopia , Humanos , Laparoscopia/métodos , Hérnia Inguinal/cirurgia , Herniorrafia/métodos , Infecção da Ferida Cirúrgica/cirurgia , Cicatrização , Hematoma/cirurgia , Resultado do TratamentoRESUMO
Lissajous micro scanners are very attractive in compact laser scanning applications for biomedical endoscopic imaging, such as confocal microscopy, endomicroscopy or optical coherence tomography. The scanning frequencies have a very important effect on the quality of the resulting Lissajous scanning imaging. In this paper, we propose a frequency selection rule for high definition and high frame-rate (HDHF) Lissajous scanning imaging, by deriving the relationship among the scanning field of view (FOV), actuation frequencies and pixel size based on the characteristics of the scanning trajectory. The minimum sampling rate based on the proposed frequency selection rule is further discussed. We report a lead zirconate titanate piezoelectric ceramic (PZT) based Lissajous fiber scanner to achieve HDHF Lissajous scanning imaging. Based on the frequency selection rule, different frequency combinations are calculated, under which the Lissajous fiber scanner can work at the frame rate (FR) of 10â Hz, 20â Hz, 40â Hz and 52â Hz. The trajectory evolution of the Lissajous scanning at the frame rate of 10â Hz has been obtained to verify the applicability of the proposed rule. The measured resolution of the scanner is 50.8 lp/mm at the unit optical magnification, and the measured FOV at the FR of 10â Hz and 40â Hz are 1.620 mm ×1.095 mm and 0.405 mm ×0.27 mm, respectively. HDHF Lissajous scanning images of the customized spatial varying binary pattern are obtained and reconstructed at the FR of 10â Hz and 40â Hz, demonstrating the practicability of the frequency selection rule.
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Alternating current (AC)-driven quantum-dot light-emitting diodes (QLEDs) are superior to direct current-driven QLEDs because they can be directly integrated into household AC electricity and have high stability. However, achieving high-performance AC-driven QLEDs remains challenging. In this work, a bipolar QLED with coplanar electrodes is realized by horizontally connecting a regular QLED and an inverted QLED in series using an Al bridging layer. The bipolar QLED can be turned on with either a positive or a negative bias voltage, with a high external quantum efficiency (EQE) of 22.9%. By replacing the Al with Ag, the resistances of the electron transport layers are effectively reduced, and thus the bipolar QLED shows an enhanced brightness of 16370 cd m-2 at 15 V. By connecting multiple bipolar QLEDs in series, the resulting light source can be directly driven by a 220 V/50 Hz household power supply without the need for back-end electronics. The bipolar QLED can also be realized by vertically stacking a regular QLED and an inverted QLED with a metallic intermediate connection layer. It is demonstrated that the coplanar or vertical bipolar QLEDs could find potential applications in household AC electricity play-and-plug solid-state lighting and single- or double-sided displays.
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A zinc supracluster [Zn24(ATZ)18(AcO)30(H2O)1.5]·(H2O)3.5 (Zn24), and a 1D zinc supracluster chain {[Zn24(ATZ)18(AcO)30(C2H5OH)2(H2O)3]·(H2O)2.5}n (1-D⊂Zn24) with molecular diameters of 2 nm were synthesized under regulatory solvothermal conditions or the micro bottle method. In an N,N-dimethylformamide solution of Zn24, Fe3+, Ni2+, Cu2+, Cr2+ and Co2+ ions exhibited fluorescence-quenching effects, while the rare earth ions Ce3+, Dy3+, Er3+, Eu3+, Gd3+, Ho3+, La3+, Nd3+, Sm3+, and Tb3+showed no obvious fluorescence quenching. In ethanol solution, the Zn24 supracluster can be used to selectively detect Ce3+ ions with excellent efficiency (limit of detection (LOD) = 8.51 × 10-7 mol/L). The Zn24 supracluster can also detect wavelengths between 302 and 332 nm using the intensity of the emitted light.
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FBXL19 is a member of the Skp1-Cullin-F-box family of E3 ubiquitin ligases and is linked to a variety of vital biological processes, such as cell proliferation, migration, and differentiation. Previous studies have identified it as an oncogene in breast cancer and glioma. However, its role in hepatocellular carcinoma (HCC) remains unclear. To comprehensively elucidate its role in tumour biology and its underlying mechanisms, a variety of sophisticated methods, including bioinformatics analysis, RNA-sequencing technique, and in vitro cell biology experiments, were used. Here, we found that FBXL19 was upregulated in patients with HCC and correlated with poor prognosis. In in vitro experiments, the specific targeting of short hairpin RNAs via lentiviruses successfully induced the knockdown of FBXL19, resulting in notable inhibition of the proliferation, migration, and invasion of HCC cells. Furthermore, FBXL19 downregulation resulted in significant induction of G0/G1 phase cell cycle arrest. Importantly, FBXL19 knockdown inhibited tumour malignant behaviour primarily by inactivating extracellular signal-regulated protein kinase 1/2 and p38 mitogen-activated protein kinases. In conclusion, this study revealed that FBXL19 was upregulated in patients with HCC, and that its expression was negatively correlated with prognosis. Thus, FBXL19 displays oncogenic properties in HCC by activating mitogen-activated protein kinase signalling.
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The effects of exogenous γ-aminobutyric acid (GABA) and melatonin (MT) on tomato seed germination and shoot growth exposed to cadmium stress were investigated. On the one hand, treatment with MT (10-200 µM) or GABA (10-200 µM) alone could significantly relieve cadmium stress in tomato seedlings, which is reflected in increasing the germination rate, vigor index, fresh weight, dry weight and radicle lengths of tomato seeds, as well as the soluble content compared to the absence of exogenous treatment, and the alleviating effect reached the peak in the 200 µM GABA or 150 µM MT alone. On the other hand, exogenous MT and GABA showed synergistic effects on the germination of tomato seed under cadmium stress. Moreover, the application of 100 µM GABA combined with 100 µM MT markedly decreased the contents of Cd and MDA by upregulating the activities of antioxidant enzymes, thereby alleviating the toxic effect of cadmium stress on tomato seeds. Collectively, the combinational strategy showed significant positive effects on seed germination and cadmium stress resistance in tomato.
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Melatonina , Solanum lycopersicum , Germinação , Melatonina/farmacologia , Cádmio/toxicidade , Sementes , Plântula , Antioxidantes/farmacologia , Ácido gama-Aminobutírico/farmacologiaRESUMO
Rhizosphere microbiota play an important role in regulating soil physical and chemical properties and improving crop production performance. This study analyzed the relationship between the diversity of rhizosphere microbiota and the yield and quality of flue-cured tobacco at different transplant times (D30 group, D60 group and D90 group) and in different regions [Linxiang Boshang (BS) and Linxiang ZhangDuo (ZD)] by high-throughput sequencing technology. The results showed that there were significant differences in the physicochemical properties and rhizosphere microbiota of flue-cured tobacco rhizosphere soil at different transplanting times, and that the relative abundance of Bacillus in the rhizosphere microbiota of the D60 group was significantly increased. RDA and Pearson correlation analysis showed that Bacillus, Streptomyces and Sphingomonas were significantly correlated with soil physical and chemical properties. PIGRUSt2 function prediction results showed that compared with the D30 group, the D60 group had significantly increased metabolic pathways such as the superpathway of pyrimidine deoxyribonucleoside salvage, allantoin degradation to glyoxylate III and pyrimidine deoxyribonucleotides de novo biosynthesis III metabolic pathways. The D90 group had significantly increased metabolic pathways such as ubiquitol-8 biosynthesis (prokaryotic), ubiquitol-7 biosynthesis (prokaryotic) and ubiquitol-10 biosynthesis (prokaryotic) compared with the D60 group. In addition, the yield and quality of flue-cured tobacco in the BS region were significantly higher than those in the ZD region, and the relative abundance of Firmicutes and Bacillus in the rhizosphere microbiota of flue-cured tobacco in the BS region at the D60 transplant stage was significantly higher than that in the ZD region. In addition, the results of the hierarchical sample metabolic pathway abundance map showed that the PWY-6572 metabolic pathway was mainly realized by Paenibacillus, and that the relative abundance of flue-cured tobacco rhizosphere microbiota (Paenibacillus) participating in PWY-6572 in the D60 transplant period in the BS region was significantly higher than that in the ZD region. In conclusion, different transplanting periods of flue-cured tobacco have important effects on soil physical and chemical properties and rhizosphere microbial communities. There were significant differences in the rhizosphere microbiota and function of flue-cured tobacco in different regions, which may affect the performance and quality of this type of tobacco.
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Fraxinus angustifolia is a type of street tree and shade tree with ornamental value. It has a beautiful shape and yellow or reddish purple autumn leaves, but its leaf color formation mechanism and molecular regulation network need to be studied. In this study, we integrated the metabolomes and transcriptomes of stage 1 (green leaf) and stage 2 (red-purple leaf) leaves at two different developmental stages to screen differential candidate genes and metabolites related to leaf color variation. The results of stage 1 and stage 2 transcriptome analysis showed that a total of 5,827 genes were differentially expressed, including 2,249 upregulated genes and 3,578 downregulated genes. Through functional enrichment analysis of differentially expressed genes, we found that they were involved in flavonoid biosynthesis, phenylpropanoid biosynthesis, pigment metabolism, carotene metabolism, terpenoid biosynthesis, secondary metabolite biosynthesis, pigment accumulation, and other biological processes. By measuring the metabolites of Fraxinus angustifolia leaves, we found the metabolites closely related to the differentially expressed genes in two different periods of Fraxinus angustifolia, among which flavonoid compounds were the main differential metabolites. Through transcriptome and metabolomics data association analysis, we screened nine differentially expressed genes related to anthocyanins. Transcriptome and qRT-PCR results showed that these nine genes showed significant expression differences in different stages of the sample, and we speculate that they are likely to be the main regulatory factors in the molecular mechanism of leaf coloration. This is the first time that we have analyzed the transcriptome combination metabolome in the process of leaf coloration of Fraxinus angustifolia, which has important guiding significance for directional breeding of colored-leaf Fraxinus species and will also give new insights for enriching the landscape.
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Fraxinus , Transcriptoma , Transcriptoma/genética , Antocianinas/genética , Fraxinus/genética , Melhoramento Vegetal , Perfilação da Expressão Gênica/métodos , Folhas de Planta/genética , Flavonoides , MetabolômicaRESUMO
CH4 -CO2 reforming is a good way to convert two environmentally harmful greenhouse gases into a high value syngas. However, the catalytic activity and stability of the catalysts need to be further improved. In this paper, the effects of promoter Y and calcination temperature on the catalytic activity and stability of Co/WC-AC catalysts were investigated. The catalysts were characterized by BET, XRD, CO2 -TPD, H2 -TPR, XPS, and TG-DSC. XPS and H2 -TPR. The results indicated that the introduction of Y decreased the reduction temperature of Co2 O3 species and facilitated the formation of Co2+ species. Meanwhile, the addition of Y increased the content of lattice oxygen on the catalyst surface, which enhanced the carbon elimination capacity of the catalyst. The TG-DSC results showed that the activity and stability of the catalysts calcined at 550 °C were poor due to the presence of carbon materials with weak carbon interactions on the catalyst support surface. Meanwhile, the catalyst calcined at 700 °C lead to the collapse of the pores due to the high calcination temperature, which eventually led to the decrease of the catalyst stability. It was found that the Co-Y/WC-AC catalysts prepared at the calcination temperature of 600 °C had the best catalytic activity and stability.
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Comparative study of macrofaunal assemblages in seagrass meadows and neighboring seabeds along the southeastern coast of Shandong Peninsula, China were performed. A total of 136 species were identified, including polychaetes (49 species), crustaceans (28), molluscs (58), and echinoderms (1). Species numbers of macrofauna in seagrass meadows and the neighboring seabeds were 52 and 65, respectively, whereas those in autumn were 90 and 56, respectively. Average macrofaunal abundances in spring in seagrass and neighboring seabeds were 2388.9 and 2516.7 ind./m2, respectively, whereas those in autumn were 11,689.0 and 1733.3 ind./m2, respectively. Ranges of species richness index, evenness index, and Shannon-Wiener index in seagrass meadows and the neighboring seabeds were 1.3-2.7, 0.7-0.9, 2.8-3.8, and 1.04-2.4, 0.5-0.9, 1.6-3.4 during spring, whereas those in autumn were 0.1-4.2, 0.3-0.8, 0.8-3.6 and 1.4-3.5, 0.5-0.9, 2.2-4.5. Bottom water temperature, salinity, sediment chlorophyll a concentration, and water content were the most important environmental factors influencing macrofaunal assemblages.
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Equinodermos , Ecossistema , Animais , Clorofila A , Água , ChinaRESUMO
Tobacco (Nicotiana tabacum L.) was an important economic crop in China. A survey in Yunnan Province in the last several years showed that the incidence of tobacco root rot was 3 to 30%. In July 2021, root rot symptoms were observed with an average incidence of 5% on tobacco (cultivar Yunyan 87) in Dali (25.61° N, 100.27° E). Typical disease symptoms included plants stunted at early stages, brown-colored withering lower leaves and roots that became brown. Under high humidity conditions, symptoms of rot expanded in the roots, also the whole plant became wilted and stunted, and some plants ultimately died. Infected pieces of stem tissues and root were dissected and then sterilized with 2% NaOCl for 30 s, rinsed three times with sterile distilled water, and dried with sterilized filter paper. Three pieces were plated onto potato dextrose agar (PDA) for 3 days at 25°C with a 12-h light period. Colonies on PDA were characterized by white to pale yellow flocculent aerial mycelium, and a pink to red pigment in the agar. To induce sporulation, mycelium on PDA was transferred to carnation leaf agar (CLA) medium. After incubation for 7 days, a single spore was isolated from representative isolate 21DL16 for morphological and molecular analyses. Macroconidia observed on CLA were falcate, slightly curved, three to five septate, measured 33.1 to 53.7 × 3.2 to 4.6 µm (n=50), with a typical foot shaped basal cell. Morphological characteristics of the fungus were in agreement with the description of Fusarium graminearum (Leslie and Summerell 2006). For further identification, the internal transcribed spacer (ITS) region rDNA, translation elongation factor 1É (EF-1α) and RNA polymerase II second largest subunit (RPB2) gene were amplified and sequenced using primers ITS1/ITS4 (White et al. 1990), EF1/EF2 (O'Donnell et al. 2015) and RPB2-5F/RPB2-7cR (Reeb et al. 2004), respectively. Although the ITS sequence (GenBank accession no. OM392025) cannot distinguish F. meridionale from F. graminearum, combined phylogenetic analysis of the sequence of TEF1 (ON062055) and RPB2 (ON211932) clearly showed that the pathogen is F. meridionale that the sequences were 100% similarity, 0.0e-value and 100% query coverage to F. meridionale. Pathogenicity studies were conducted on six-leaf-stage tobacco seedlings cultivar Yunyan 87. A conidial suspension (1×105 spores/mL) was poured over the roots of tobacco seedlings. Three seedlings were treated with sterile water that served as controls. All 10 seedlings were maintained at 25°C at 70% relative humidity. After 5 days, the lower leaves showed symptoms of wilting and the roots of all inoculated seedlings become discolored, that were similar with the original symptoms, whereas the control seedlings did not develop symptoms. The fungus reisolated from the inoculated seedlings was identical to F. meridionale using the EF-1α gene sequence. To date, Fusarium root rot on tobacco in China was caused by F. oxysporium (Chen 2013). However, to the best of our knowledge, this is the first report of F. meridionale causing root rot on tobacco in China. Identification of F. meridionale as a root rot agent might provide important insight for disease management practices on tobacco caused by Fusarium species.
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Egusi watermelon has a unique egusi seed type, which could be useful for breeding both edible seeds and edible flesh in watermelon. However, the genetic basis of the unique egusi seed type is not clear. In the present study, we first reported that at least two genes with inhibitory epistasis were responsible for the thin seed coat (unique egusi seed type) in watermelon. Inheritance analysis of five populations, including F2, BC, and BCF2, suggested that the thin seed coat trait was controlled by a suppressor gene together with the egusi seed locus (eg) in egusi watermelon. Based on high-throughput sequencing technology, two quantitative trait loci located on chromosome 1 and chromosome 6 were identified for the thin seed coat trait in watermelon. One of the loci, the eg locus on chromosome 6, was finely mapped to a genomic region of 15.7 kb, which contained only one candidate gene. Comparative transcriptome analysis highlighted differentially expressed genes involved in cellulose and lignin synthesis between watermelon genotypes varying in the thickness of the seed coat and provided several potential candidate genes for the thin seed coat trait. Taken together, our data suggest that at least two genes are complementarily involved in the thin seed coat trait and will be useful for cloning novel genes. The results presented here provide a new reference for uncovering egusi seed genetic mechanisms and valuable information for marker-assisted selection in seed coat breeding.
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We showed the local polarization properties extraction method for the single incident state, all-single-mode-fiber-based spectral domain polarization-sensitive optical coherence tomography (SD-PS-OCT) system that uses the single linear-in-wavenumber spectral camera. Polarization controllers are used in the single-mode-fiber-based SD-PS-OCT system to provide a compact structure with polarization state stability. The local polarization properties of the birefringent sample are extracted from the cumulative polarization properties iteratively. The reconstructed polarization images demonstrate the local polarization properties extraction ability of the system.
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We introduce a calcium carbonate birefringent crystal into an Er-fiber laser mode-locked by a saturable absorber, where dual-comb ultrashort pulses with orthogonal polarization have been obtained. The two ultrashort pulse trains from the laser exhibit polarization contrast ratios of 30â dB and 20â dB, indicating that the dual-comb mode-locking is due to the polarization-multiplexing mechanism. The dual-comb ultrashort pulses have central wavelengths of 1564.41â nm and 1564.51â nm, and pulse durations of 825 fs and 805 fs respectively. The optical spectra and pulse durations of the asynchronous ultrashort pulses are nearly identical, so that the output of the laser could be directly used for dual-comb applications. Besides, the repetition-rate difference of the two mode-locked pulses is 673â Hz, while its drift is only 0.093â Hz within 2 hours' time. The low drift of the repetition-rate difference manifests the single-cavity dual-comb Er-fiber laser has a high stability and high common-mode noise suppression. At last, we have tested the dual-comb fiber laser in a ranging experiment, where clear interferogram signal can be observed. The experimental results prove that this single-cavity dual-comb Er-fiber laser based on the birefringent crystal and saturable absorber can be a potential source for spectroscopy, optical imaging, absolute distance measurement and other dual-comb applications.