A novel single-base mutation in CaSGR1 confers the stay-green phenotype in pepper

The stay-green trait is of considerable importance in extending the shelf life of green pepper fruit(Capsicum annuum L.)and in enhancing the appearance of ornamental plants.The study revealed the genetic and regulatory mechanisms of the stay-green trait in pepper,which will aid in the selection of ornamental pepper varieties.In this study,a pepper mutant with stay-green fruit named TNX348 was identified from a germplasm resource bank.Two segregating populations were constructed using the stay-green mutant TNX348 and then used in bulked segregant analysis combined with RNA sequencing and linkage analyses.The causal gene of the stay-green trait was mapped to an approximately 131-kb region,and a senescence-induced chloroplast protein gene,CaSGR1(Capana01g000359),was identified as a candidate gene.Sequencing analysis revealed a G→A single-base mutation of CaSGR1 in TNX348 that led to early termination of translation.Based on the single-base mutation,a single nucleotide polymorphism(SNP)marker co-segregating with the stay-green trait was developed.Furthermore,in transcriptome analysis,expression patterns of 11 hormone transduction-related transcription factors,such as abscisic acid-insensitive(ABI),abscisic acidresponsive element-binding factor(ABF),and NAC transcription factor,were similar or opposite to that of CaSGR1.The results indicated that the transcription factors might mediate chlorophyll degradation by regulating the expression of CaSGR1.

MXene-Based Quantum Dots Optimize Hydrogen Production via Spontaneous Evolution of Cl-to O-Terminated Surface Groups

MXene quantum dots(MQDs)offer wide applications owing to the abundant surface chemistry,tunable energy-level structure,and unique properties.However,the application of MQDs in electrochemical energy conversion,including hydrogen evolution reaction(HER),remains to be realized,as it remains a challenge to precisely control the types of surface groups and tune the structure of energy levels in MQDs,owing to the high surface energy-induced strong agglomeration in post-processing.Consequently,the determination of the exact catalytically active sites and processes involved in such an electrocatalysis is challenging because of the complexity of the synthetic process and reaction conditions.Herein,we demonstrated the spontaneous evolution of the surface groups of the Ti_(2)CT_(x)MQDs(x:the content of O atom),i.e.,replacement of the-Cl functional groups by O-terminated ones during the cathode reaction.This process resulted in a low Gibbs free energy(0.26 eV)in HER.Our steady Ti_(2)CO_(x)/Cu_(2)O/Cu foam systems exhibited a low overpotential of 175 mV at 10 mA cm^(-2)in 1 M aq.KOH,and excellent operational stability over 165 h at a constant current density of-10 mA cm^(-2).

Synthesis of HTLcs modified by K_(3)PO_(4) for side chain alkylation of toluene with methanol

A series of calcined HTLcs catalysts were prepared and modified with potassium phosphate by impregnation method to clarify the influence of catalyst alkalinity on the side chain alkylation of toluene with methanol for synthesis of ethylbenzene and styrene.The catalysts were characterized by X-ray diffraction(XRD),N_(2)physical adsorption-desorption,Fourier-transform infrared spectroscopy(FT-IR),Scanning electron microscopy(SEM),X-ray photoelectron spectrometry(XPS),NH_(3)temperature-programmed desorption(NH_(3)-TPD)and CO_(2)temperature-programmed desorption(CO_(2)-TPD).It was found that the selectivity of styrene was highest(39.25%)when the K_(3)PO_(4)loading was 7.5 wt%.And the total yield of styrene and ethylbenzene could reach 65.08%with 10 wt%K_(3)PO_(4)loading.This might due to the fact that the addition of K_(3)PO_(4)could adjust the acid and basic sites of catalysts.In addition,appropriate strength and amount of basic sites were favorable to producing more styrene.

Quantum Dots Compete at the Acme of MXene Family for the Optimal Catalysis

It is well known that two-dimensional(2D)MXene-derived quan-tum dots(MQDs)inherit the excellent physicochemical properties of the parental MXenes,as a Chinese proverb says,“Indigo blue is extracted from the indigo plant,but is bluer than the plant it comes from.”Therefore,0D QDs harvest larger surface-to-volume ratio,outstanding optical properties,and vigorous quantum confinement effect.Currently,MQDs trigger enormous research enthusiasm as an emerging star of functional materials applied to physics,chemistry,biology,energy conversion,and storage.Since the surface properties of small-sized MQDs include the type of surface functional groups,the functionalized surface directly determines their performance.As the Nobel Laureate Wolfgang Pauli says,“God made the bulk,but the surface was invented by the devil,”and it is just on the basis of the abundant surface functional groups,there is lots of space to be thereof excavated from MQDs.We are witnessing such excellence and even more promising to be expected.Nowadays,MQDs have been widely applied to catalysis,whereas the related reviews are rarely reported.Herein,we provide a state-of-the-art overview of MQDs in catalysis over the past five years,ranging from the origin and development of MQDs,synthetic routes of MQDs,and functionalized MQDs to advanced characterization techniques.To explore the diversity of catalytic application and perspectives of MQDs,our review will stimulate more efforts toward the synthesis of optimal MQDs and thereof designing high-performance MQDs-based catalysts.

Comparative Transcriptome Analysis between Cytoplasmic Male-sterile Line and Its Maintainer During the Floral Bud Development of Pepper

The male-sterile line has been largely used in the hybrid seed production of pepper, which can effectively improve the efficiency of hybrid seed production. However, the formation mechanism of male sterility in pepper remains unclear. In the present study, we compared the gene expression patterns between pepper cytoplasmic male sterile line 9704 A and its maintainer 9704 B during floral bud development using RNA sequencing technology. A total of 547 976 and 2 416 Differentially Expressed Genes(DEGs) were identified in the stage S1, S2 and S3, respectively,and more than 70% of the DEGs were down-regulated in the sterile line. Gene Ontology(GO), and Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment analyses were performed to further understand the functions of these identified DEGs. The results showed that the DEGs were mainly enriched in pathways of starch and sucrose metabolism, pentose and glucuronate interconversions. A number of genes, such as MS1, PME5, ATPB, and lots of transcription factors were found down-regulated in the sterile line, and we also identified a series of genes with large differences in expression patterns between sterile line and maintainer line. Collectively, our findings laid a foundation for further molecular breeding in pepper and provided new insights into its mechanism underlying the male sterility.

Surface chemistry of MXene quantum dots:Virus mechanism-inspired mini-lab for catalysis

Scientific research is currently more interdisciplinary.Researchers have parsed the surface structure of virus,constructed the interaction model of virus-receptors,offering the clues for studying efficient targeted drugs.Likewise,catalysis is also highly relevant to modern human life.Exploring the surface structure and physicochemical properties of catalysts is of great significance for the design of efficient catalysts.Great progresses have been made for endowing specific physicochemical properties of catalysts through controlling the size of materials and coordination chemistry of active sites,particularly at nanometer scale since Sir John Meurig Thomas and Tao Zhang’s early ground-breaking contribution,with casting on a very surface issue.Herein,functional regulation renders the emerging MXene quantum dots(MQDs)excel in contrast to the typical carbon-based quantum dots.In fact,similar to the interaction of virus-receptors model,the surface functional groups decorated MQDs provide a mini-lab to afford a variety of adjustments,involved with the type modification and electronic structure tuning of groups as well as their arrangement,together with the interaction between the groups and active materials/support,ultimately for packaging or designing high-activity catalysts.

Fractionation and structural identification of antibiotic activity substances from <i>Streptomyces herbaricolor</i>HNS2-2

Four groups of antibiotic activity compounds were separated and purified from the ethyl acetate fraction of a broth culture of Streptomyces herbaricolor HNS2-2.Trace analyses were performed and anti-microbial activities were determined. The antibiotic activity compounds were identified as quercetin dehydrate ①, p-hydroxyphenyl ②, 4’-hydroxyflavanone ③, and 3-hydroxyflavone ④ based on spectroscopic data. Compounds 1-4 showed significant antimicrobial activities against Staphylococcus aureus and the tobacco mosaic virus in vitro, suggesting their potential agricultural and medical applications.

Association of the p73 Gene G4C14-to-A4T14 Polymorphism with Increased Gastric Cancer Risk in a Northwestern Chinese Population

OBJECTIVE To evaluate the p73 gene G4C14-to-A4T14 double nucleotide polymorphism with both increased gastric cancer(GC) risk and different histological subtypes of GC in a northwestern Chinese population. METHODS Genotyping of the polymorphism of the p73 gene was conducted with PCR-CTPP. RESULTS All 385 GC patients including 305 diffuse-type and 80 intestinal-type cases and 412 healthy controls were investigated.The frequencies of p73 AT/AT,AT/GC,and GC/GC genotypes were 28.1%,47.1%,and 24.8% in the controls,and were 22.0%,45.0%,and 33.0% in GC cases respectively;the GC/GC homozygote frequency was higher in GC cases,mainly in diffuse type compared to the controls with OR=1.71(1.16～2.51) and 1.87 (95%CI,1.24～2.81) respectively.The results showed that carriers of the p73 G4A GC/GC homozygote had a 1.71-time higher risk of GC,especially of the diffuse-type GC compared to the controls. The carriers of the AT/GC heterozygote also had a slightly increased risk of GC cancer,mainly on intestinal-type GC.This is the first report that the p73 G4A double-nucleotide polymorphism is associated with an increased risk of diffuse-type gastric cancer. CONCLUTION The p73 G4A GC/GC genotype is associated with an increased risk of gastric cancer,especially of the GC diffuse-type.

Antioxidant capacity of chemical constituents and antiinflammatory activity of ethanol extract from Semen sojae praeparatum

Semen sojae praeparatum is a kind of plant resource used both as medicine and food and has been used in preventing oxidative damage and treating some clinical inflammatory symptoms. However, the involved active mechanisms and the pharmacodynamic material basis of this fermented legume are not clear. Therefore, this study attempts to evaluate the chemical composition and provide further insights of the antioxidant activities of isolated compounds. In the meantime, the anti-inflammatory role and potential mechanisms were investigated. The all results revealed that genistein and it derivatives showed significantly high antioxidant activity. In anti-inflammatory assay, Semen sojae praeparatum extract significantly suppressed acute and chronic inflammation. In vitro results also verified that the extract markedly inhibited inflammatory mediator production at 120 mg/mL. These effects are consistent with previous research about anti-inflammatory activity of flavonoids. Our research also discussed the anti-inflammatory activity of detected constituents on the basis of literature data. It could be concluded that genistein might be showed the most powerful anti-inflammatory activity due to the presence of the phenolic hydroxyl at C-5, C-7 and C-4'. These finding highlight the very powerful antioxidant activity and anti-inflammatory activity of genistein and Semen sojae praeparatum extract, thereby considering its availability as a medicinal or an edible treatment against oxidative and inflammatory diseases.

面向碱性析氢反应的原子级优化Fe-Pt金属间化合物催化剂表面终结态探索

Controlling the atomic arrangement of elemental atoms in intermetallic catalysts to govern their surface and subsurface properties is a crucial but challenging endeavor in electrocatalytic reactions.In hydrogen evolution reaction(HER),adjusting the d-band center of the conventional noble-metallic Pt by introducing Fe enables the optimization of catalytic performance.However,a notable gap exists in research on the effective transition from disordered Fe/Pt alloys to highly ordered intermetallic compounds(IMCs)such as FePt_(3)in the alkaline HER,hampering their broader application.In this study,a series of catalysts FePt_(3-x)H(x=5,6,7,8 and 9)supported on carbon nanotubes(CNTs)were synthesized via a simple impregnation method,along with a range of heat treatment processes,including annealing in a reductive atmosphere,to regulate the order degree of the arrangement of Fe/Pt atoms within the FePt_(3)catalyst.By using advanced microscopy and spectroscopy techniques,we systematically explored the impact of the order degree of FePt_(3)in the HER.The as-prepared FePt_(3)-8H exhibited notable HER catalytic activity with low overpotentials(η=37 mV in 1.0 mol L^(-1)KOH)at j=10 mA cm^(-2).The surface of the L1_(2)FePt_(3)-8H catalyst was demonstrated to be Pt-rich.The Pt on the surface was not easily oxidized due to the unique Fe/Pt coordination,resulting in significant enhancement of HER performance.

Highly-efficient CoRuO_(x)nanocatalysts for acidic oxygen evolution:The merit of optimum ordering degree of carbon nanotube support

Hydrogen production from proton exchange membrane water electrolysis is constrained by the sluggish kinetics of the anodic oxygen evolution reaction.RuO_(2)has attracted considerable attention due to its low reaction overpotential,but its inferior stability remains a major challenge.Herein,a strategy is proposed to enhance the catalytic activity and stability of CoRuOx nanoparticles by doping Co and regulating the ordering degree of carbon nanotubes(CNTs)by air annealing.It was found that the CoRuOx@CNTs-300 catalyst exhibited the best catalytic activity and stability when the annealing temperature was 300°C.At the current density of 10 mA cm−2,the overpotential of this catalyst was only 201 mV,which was nearly 100 mV lower than that of commercial RuO_(2)(300 mV).Surprisingly,there was no significant increase in the overpotential when tested at a current density of 10 mA cm−2 for 50 h.The density functional theory calculations indicate that the high activity of the catalyst is due to the electronic coupling of CoRuOx nanoparticles and CNTs,and that the introduction of Co and CNTs improves the electronic structure and solvation energies of the Ru in the active site,dramatically increasing the structural stability.

Study on myocardial infarction based on nationwide inpatient sample database:a bibliometric analysis from 2000 to 2022

Background:Studies on myocardial infarction(MI)based on large medical databases have become popular in recent years.The influence of the National Inpatient Sample(NIS),the largest collection of administrative healthcare data across the United States,on the field of MI has not been well investigated.This study aimed to quantify the contribution of NIS to MI research using bibliometric methods.Methods:We searched the Web of Science Core Collection database to identify publications on MI using NIS from 2000 to 2022.Bibliometric indicators,such as the number of publications,citations,and Hirsch index(H-index),were summarized by years,authors,organizations,and journals.VOSviewer and CiteSpace software were used to analyze the keywords and trends of the hot spots.Results:A total of 342 articles on MI based on NIS were included.A significant growth in outputs related to MI using the NIS from 2000 to 2020 was observed.The publications were mainly from the United States.The Mayo Clinic was the most prolific institution and had the most citations and the highest H-index.The American Journal of Cardiology ranked first among journals with the highest number of publications,citations,and H-index.Mortality and healthcare management are the main focuses of this field.Personalized risks and care are receiving increased attention.Conclusion:This study suggests that NIS significantly contributes to high-quality output in MI research.More efforts are needed to improve the impact of knowledge gained from the NIS on MI.

层间Cu^(+)离子重排诱导体系超导转变

层间离子插层的层状材料表现出多样有趣的物理和化学特性.为了获得奇特的二维材料,离子客体对晶体的掺杂和调控在材料科学中得到广泛应用.然而,在离子插层层状材料的研究中,由层间结构变化所引起的性质研究较少.因此,在本文中我们展示了由于Cu_(0.65)NbS_(2)纳米片的新型层间结构导致的超导性.随着维度的降低,层间铜离子的占位从体相结构时的单一四面体位点转变为混合四面体位点,导致原本的普通金属态转变成超导体.值得注意的是,材料的超导转变温度具有强烈的厚度依赖性,并且随厚度变化呈火山曲线,展现出了与纯NbS2体系不同的随样品层数变化关系.操控层间离子的排列方式将成为促进二维材料领域新本征性质研究的重要方法之一.

A chiral lead-free tin(Ⅳ)-based halide organic-inorganic semiconductor with dielectric switching and phase transition

Chiral organic-inorganic metal halide semiconductors(OIMHSs)have recently attracted numerous interests due to their unique chirality,structural tunability,and extensive physical properties.However,most reported chiral OIMHSs contain toxic lead,which will be a potential obstacle to their further applications.Herein,we successfully synthesized a novel chiral lead-free tin(IV)-based OIMHS[(R)-3-hydroxyquinuclidinium]_(2)SnCl_(6)([R-HQ]_(2)SnCl_(6)).It exhibits a wide band gap(Eg)of about 4.11 eV.Moreover,[R-HQ]_(2)SnCl6 undergoes a phase transition around 330 K(Tc)and shows distinct dielectric switching characteristics with good repeatability.This work enriches the chiral lead-free OIMHS family and stimulates further exploration of chiral lead-free OIMHS switching materials.

Inverted-design for highly-active hydrogen evolution electrocatalyst of MoS_(2)@Ni_(3)S_(2)core-shell via unlocking the potential of Mo

Through inverted-design rather than modifying the generally-assumed S active sites in popular MoS_(2),we unlock the potential of Mo sites and successfully prepared novel MoS_(2)@Ni_(3)S_(2)/NF core-shell nanospheres as a catalyst for the high-performance hydrogen evolution reaction(HER).TheΔGH at the Mo site is optimized via Ni_(3)S_(2)to achieve excellent HER activity.At low current densities,it has similar activity to the Pt/C.However,its performance is better than Pt/C at high density.Moreover,our catalyst shows a considerable stability at a variety of current densities for 50 h,promising to substitute noble metal catalysts in application of commercial alkaline electrocatalysts.

Screening of Ginkgo Individuals with Superior Growth Structural Characteristics in Different Genetic Groups Using Terrestrial Laser Scanning(TLS)Data

With the concept of sustainable management of plantations,individual trees with excellent characteristics in plantations have received attention from breeders.To improve and maintain long-term productivity,accurate and high-throughput access to phenotypic characteristics is essential when establishing breeding strategies.Meanwhile,genetic diversity is also an important issue that must be considered,especially for plantations without seed source information.This study was carried out in a ginkgo timber plantation.We used simple sequence repeat(SSR)markers for genetic background analysis and high-density terrestrial laser scanning for growth structural characteristic extraction,aiming to provide a possibility of applying remote sensing approaches for forest breeding.First,we analyzed the genetic diversity and population structure,and grouped individual trees according to the genetic distance.Then,the growth structural characteristics(height,diameter at breast height,crown width,crown area,crown volume,height to living crown,trunk volume,biomass of all components)were extracted.Finally,individual trees in each group were comprehensively evaluated and the best-performing ones were selected.Results illustrate that terrestrial laser scanning(TLS)point cloud data can provide nondestructive estimates of the growth structural characteristics at fine scale.From the ginkgo plantation containing high genetic diversity(average polymorphism information content index was 0.719)and high variation in growth structural characteristics(coefficient of variation ranged from 21.822%to 85.477%),11 excellent individual trees with superior growth were determined.Our study guides the scientific management of plantations and also provides a potential for applying remote sensing technologies to accelerate forest breeding.

Joining of Zirconia and Ti-6Al-4V Using a Ti-based Amorphous Filler

Polycrystalline ZrO2-3 mol.%Y2O3 was brazed to Ti-6Al-4V by using a Ti47Zr28Cu14Ni11（at.%） amorphous ribbon at 1123–1273 K in a high vacuum. The influences of brazing temperature on the microstructure and shear strength of the joints were investigated. The interfacial microstructures can be described as ZrO2/TiO＋TiO2＋Cu2Ti4O＋Ni2Ti4O/α-Ti＋（Ti,Zr）2（Cu,Ni） eutectic/acicular Widmanst¨aten structure/Ti–6Al–4V alloy. With the increase in the brazing temperature, the thickness of the TiO＋TiO2＋Cu2Ti4O＋Ni2Ti4O layer reduced, the content of the α-Ti＋（Ti,Zr）2（Cu,Ni） eutectic phase decreased, while that of the coarse α-Ti phase gradually increased. The shear strength of the joints did not show a close relationship with the thickness of the TiO＋TiO2＋Cu2Ti4O＋Ni2Ti4O layer. However, when the coarse （Ti,Zr）2（Cu,Ni） phase was non-uniformly distributed in the α-Ti phase, or when α-Ti solely situated at the center of the joint, forming a coarse block or even connecting into a continuous strip, the shear strength greatly decreased.

Opposite effects of miR-155 in the initial and later stages of lipopolysaccharide(LPS)-induced inflammatory response

Although microRNA-155(miR-155)is considered a pro-inflammatory mediator,cumulative evidence indicates that it also has anti-inflammatory effects in macrophages and dendritic cells.In this study,we identified the dramatic expression changes of more than half of potential miR-155-targeted genes upon lipopolysaccharide(LPS)stimulation;223 genes were down-regulated and 85 genes were up-regulated,including suppressor of cytokine signaling 1(SOCS1)and transforming growth factor-β-activated kinase 1-binding protein 2(TAB2),two well-known genes involved in miR-155-mediated regulation of the Toll-like receptor 4(TLR4)signaling pathway.We also found that miR-155 acted as an anti-inflammatory mediator in the initial stage of LPS-induced inflammatory response mainly through repressing TAB2 protein translation,and as a proinflammatory mediator by down-regulating SOCS1 in the later stage.Meanwhile,overexpression of TAB23'untranslated region(UTR)in macrophages promoted the development of endotoxin tolerance by competing for binding with miR-155,which resulted in an elevated expression level of SOCS1 protein.These findings provide new insights for understanding the regulatory mechanisms in fine-tuning of LPS-induced innate immune response.

Efficient Synthesis of Triarylamines Catalyzed by Copper(I)Diazabutadiene Complexes

Cuprous chloride was coordinated by diazabutadiene(DAB-R)ligands to form Cu(I)-(DAB-R)complexes,most of which have a 1∶1 ratio of Cu to DAB-R as reported.In the case of a special DAB-iPP,N,N'-bis(2,6-diiso-propylphenyl)-1,4-diaza-1,3-butadiene,an unexpected composition of complex was found with the formula Cu(I)Cl(DAB)_(2).When employed as catalyst for triarylamine synthesis from the coupling of aryl halides with pri-mary and secondary arylamines,the new Cu(I)-(DAB-iPP)complex displayed high efficiency.

Effect of parameters on interface of the brazed ZrO_2 ceramic and Ti-6Al-4V joint using Ti-based amorphous filler

A commercially available Ti47Zr2sCu14Nin （at. pct） amorphous filler foil was used to join ZrO2 ceramic and Ti-6A1-4V alloy. According to experimental observations, the interface microstructure accounts for the mechanical properties of the joints. The effects of brazing conditions and parameters on the joint properties were investigated. The joint shear strength showed the highest value of about 108 MPa and did not monotonously increase with the brazing time increasing. It was shown that decreasing of brazing cooling rate and appropriate filler foil thickness gave higher joint strength.