The no-cloning theorem has sparked considerable interest in achieving high-fidelity approximate quantum cloning.Most of the previous studies mainly focused on the cloning of single particle states,and cloning schemes ...The no-cloning theorem has sparked considerable interest in achieving high-fidelity approximate quantum cloning.Most of the previous studies mainly focused on the cloning of single particle states,and cloning schemes used there are incapable of cloning quantum entangled states in multipartite systems.Few schemes were proposed for cloning multiparticle states,which consume more entanglement resources with loss of qubits,and the fidelity of the cloned state is relatively low.In this paper,cloning schemes for bipartite and tripartite entangled states based on photonic quantum walk and entanglement swapping are proposed.The results show that according to the proposed schemes,two high-fidelity(up to 0.75)cloned states can be obtained with less quantum resource consumption.Because of the simple cloning steps,few quantum resources and high fidelity,these schemes are both efficient and feasible.Moreover,this cloning machine eliminates the need for tracing out cloning machine,thereby minimizing resource waste.展开更多
Since the discovery of carbon dots(CDs)in 2004,the unique photoluminescence phenomenon of CDs has attracted widespread attention.However,the molecular weight of CDs has not been adequately quantified at present,due to...Since the discovery of carbon dots(CDs)in 2004,the unique photoluminescence phenomenon of CDs has attracted widespread attention.However,the molecular weight of CDs has not been adequately quantified at present,due to CDs are atomically imprecise and their molecular weight distribution is broad.In this paper,a series of Pluronic-modified CDs were prepared and the structure of the CDs was briefly analyzed.Subsequently,a molecular weight measurement method based on colligative properties was developed,and the correction coefficient in the algorithm was briefly analyzed.The calculated molecular weight was applied to the determination of surface adsorption capacity.This work provided a method for averaging the molecular weight of atomically imprecise particulate materials,which is expected to provide new opportunities in related fields.展开更多
High-quality antiferromagnetic(AFM)θ-phase manganese nitride(MnN)films were successfully grown on MgO(001)substrates by plasma-assisted molecular beam epitaxy.Structural analysis confirms the high-quality MnN film ha...High-quality antiferromagnetic(AFM)θ-phase manganese nitride(MnN)films were successfully grown on MgO(001)substrates by plasma-assisted molecular beam epitaxy.Structural analysis confirms the high-quality MnN film has a tetragonal distortion with a c/a ratio of~0.98.The film exhibits exceptional stability in both aqueous and ambient conditions,which is a crucial factor for practical applications.Electrical transport reveals its metallic behavior with an upturn at low temperatures,which could be attributed to the Kondo effect originated from nitrogen vacancy-induced magnetic impurities.Room temperature exchange bias has been demonstrated in a MnN/CoFeB heterostructure,verifying the AFM ordering of MnN.Considering its high Néel temperature~650 K,superior stability,and low-cost,this work highlights the epitaxial MnN films as a promising candidate for AFM spintronic applications.展开更多
This paper discusses the influence of Sb/In ratio on the transport properties and crystal quality of the 200 nm InAs_(x)Sb_(1-x)thin film.The Sb content of InAs_(x)Sb_(1-x)thin film in all samples was verified by HRXR...This paper discusses the influence of Sb/In ratio on the transport properties and crystal quality of the 200 nm InAs_(x)Sb_(1-x)thin film.The Sb content of InAs_(x)Sb_(1-x)thin film in all samples was verified by HRXRD of the symmetrical 004 reflections and asymmetrical 115 reflections.The calculation results show that the Sb component was 0.6 in the InAs_(x)Sb_(1-x)thin film grown under the conditions of Sb/In ratio of 6 and As/In ratio of 3,which has the highest electron mobility(28560 cm^(2)/V·s)at 300 K.At the same time,the influence ofⅤ/Ⅲratio on the transport properties and crystal quality of Al_(0.2)In_(0.8)Sb/InAs_(x)Sb_(1-x)quantum well heterostructures also has been investigated.As a result,the Al_(0.2)In_(0.8)Sb/InAs_(0.4)Sb_(0.6)quantum well heterostructure with a channel thickness of 30 nm grown under the conditions of Sb/In ratio of 6 and As/In ratio of 3 has a maximum electron mobility of 28300 cm^(2)/V·s and a minimum RMS roughness of 0.68 nm.Through optimizing the growth conditions,our samples have higher electron mobility and smoother surface morphology.展开更多
Chitin is the most widespread amino polysaccharide in nature. Chitin synthase （CHS） plays an important role in chitin formation in the cuticle and the peritrophic membrane （PM） lining the midgut. Total RNA was iso...Chitin is the most widespread amino polysaccharide in nature. Chitin synthase （CHS） plays an important role in chitin formation in the cuticle and the peritrophic membrane （PM） lining the midgut. Total RNA was isolated from the cuticle of Mamestra brassicae （L.） fourth instar larva, cDNA sequence was cloned by RT-PCR and Rapid Amplification of cDNA Ends （RACE）. cDNA 5 220 bp in length, contained an open reading frame of 4 704 bp coding for a polypeptide of 1 567 amino acid residues with a predicted molecular weight of 178.3 ku and its pI was 6.42. The deduced amino acid sequence from Mi brassicae （L.） shared the high level of identity with chitin synthase sequences from other insects, especially lepidopteran insects, cDNA sequence has been deposited with GenBank under accession No. GQ281761展开更多
Sea Island cotton(Gossypium barbadense L.) has been highly valued in Verticillium wilt resistance and many fiber qualities including fiber length,strength,and fineness.To identify whether
Verticillium dahliae Kleb.is a necrotrophic plant pathogen which causes serious soil borne vascular disease in cotton.The molecular basis the defense response of cotton to this pathogen is
CAP,an adenylyl cyclase-associated protein,is predicted to be involved in cytoskeletal organization and signal transduction.Recently,we found that CAP may play an important role in fuzz-like fiber cell initiation in c...CAP,an adenylyl cyclase-associated protein,is predicted to be involved in cytoskeletal organization and signal transduction.Recently,we found that CAP may play an important role in fuzz-like fiber cell initiation in cotton.For the further research,we isolated two CAP homologues from wild展开更多
Studies on the cold-responsive genes and cold signaling of woody species drop far behind in comparison to herbaceous plants.Due to similar lignified structure,perennial characteristic,and enhanced tolerance,it seems m...Studies on the cold-responsive genes and cold signaling of woody species drop far behind in comparison to herbaceous plants.Due to similar lignified structure,perennial characteristic,and enhanced tolerance,it seems much easier to find strongly antifreeze genes and obtain effective results in transgenic woody plants.In this study,Ammopiptanthus mongolicus,an evergreen,broadleaf and cold-resist leguminous shrub growing in the desert of Inner Mongolia,was used as a material for low-temperature induced gene isolation.Through differential expression analysis induced by low-temperature,thirteen up-regulated cDNAs were identified.One of them,AmEBP1,(accession number:DQ519359)confers enhanced cold-tolerance to both transgenic E.coli and transgenic Arabidopsis.Results suggest that AmEBP1 can stimulate the synthesis of ribosome and the dephosphyration of the α-subunit of initiation factor 2(eIF2α),and subsequently promote the translation process.By which the transgenic plants obtained increased cold-resistant ability.展开更多
The zinc finger proteins belong to the largest family of transcription factors.But there is little research of Cys2/His2 type zinc finger proteins in cotton,and there is no submission of correlating
At the early stage,the transcriptome sequencing technique was used to detect the differentially expressed gene CsFK111 between vine cucumber and dwarf cucumber D0462.The gene was cloned,and bioinformatics software too...At the early stage,the transcriptome sequencing technique was used to detect the differentially expressed gene CsFK111 between vine cucumber and dwarf cucumber D0462.The gene was cloned,and bioinformatics software tools were used to analyze and predict the gene family and this gene.There were 30 members of the cucumber F-box gene family.The coding region of the cucumber CsFK111 gene was full-length 1314 bp,which encoded 437 amino acids and was predicted to be located in the nucleus.The protein encoded by this gene was a non-transmembrane protein,and the prediction of the secondary structure showed thatβ-lamellar structure and irregular crimp were dominant.A comparison of the phylogenetic tree showed that it was closest to cantaloupe and belonged to the same branch.The results provided a basis for future study on the regulation mechanism of the CsFK111 gene on cucumber dwarfing and also laid a foundation for further study of FBK family proteins.展开更多
In this study,circular dichroism(CD)and molecular dynamics(MD)simulation were used to investigate the thermal unfolding pathway of staphylococcal enterotoxin B(SEB)at temperatures of 298–371 and 298–500 K,and the re...In this study,circular dichroism(CD)and molecular dynamics(MD)simulation were used to investigate the thermal unfolding pathway of staphylococcal enterotoxin B(SEB)at temperatures of 298–371 and 298–500 K,and the relationship between the experimental and simulation results were explored.Our computational findings on the secondary structure of SEB showed that at room temperature,the CD spectroscopic results were highly consistent with the MD results.Moreover,under heating conditions,the changing trends of helix,sheet and random coil obtained by CD spectral fitting were highly consistent with those obtained by MD.In order to gain a deeper understanding of the thermal stability mechanism of SEB,the MD trajectories were analyzed in terms of root mean square deviation(RMSD),secondary structure assignment(SSA),radius of gyration(R_(g)),free energy surfaces(FES),solvent-accessible surface area(SASA),hydrogen bonds and salt bridges.The results showed that at low heating temperature,domain Ⅰ without loops(omitting the mobile loop region)mainly relied on hydrophobic interaction to maintain its thermal stability,whereas the thermal stability of domain Ⅱ was mainly controlled by salt bridges and hydrogen bonds.Under high heating temperature conditions,the hydrophobic interactions in domain Ⅰ without loops were destroyed and the secondary structure was almost completely lost,while domain Ⅱ could still rely on salt bridges as molecular staples to barely maintain the stability of the secondary structure.These results help us to understand the thermodynamic and kinetic mechanisms that maintain the thermal stability of SEB at the molecular level,and provide a direction for establishing safer and more effective food sterilization processes.展开更多
The objective of the present study was to investigate the developmental expression patterns of Insulin-like growth factor-binding protein 1 (IGFBP-1) gene in different tissues of postnatal Nanjiang Mongolian Gazelles....The objective of the present study was to investigate the developmental expression patterns of Insulin-like growth factor-binding protein 1 (IGFBP-1) gene in different tissues of postnatal Nanjiang Mongolian Gazelles. Samples of heart, liver, spleen, lung, longissimus dorsi, semimembranosus, m. triceps brachii and biceps muscle of thigh were collected from a total of 36 Nanjiang Mongolian Gazelles at the age of 0, 15, 30, 60, 90 and 120 days after birth (3 males and 3 females at each age). The CDS was sequenced and ontogeny of mRNA levels of IGFBP-1 were measured by real-time fluorescence quantitative RT-PCR. The size of IGFBP-1 ORF was 792 bp encoding 263 amino acid residues, and displayed higher nucleotide/amino acid sequence identities with other ruminants compared to non-ruminants. The levels of IGFBP-1 mRNA in liver were highest (P<0.01), levels were medium in lung, spleen and heart, and the lowest in the muscles; there were no significant differences among the muscles (P>0.05). Three expression patterns of IGFBP-1 mRNA during postnatal growth from birth to day 60 were found: consistently decreasing (liver), fluctuating as increasing then decreasing (heart) or as decreasing then increasing then decreasing (spleen, lung and muscles). The results indicate that the IGFBP-1 gene is highly conserved among species, and liver has the highest expression. It was concluded that IGFBP-1 plays important roles in early postnatal growth and is expressed in a developmental-tissue-dependent manner.展开更多
Improving the energy conversion efficiency in metallic fuel(e.g.,Al)combustion is always desirable but challenging,which often involves redox reactions of aluminum(Al)with various mixed oxidizing environments.For inst...Improving the energy conversion efficiency in metallic fuel(e.g.,Al)combustion is always desirable but challenging,which often involves redox reactions of aluminum(Al)with various mixed oxidizing environments.For instance,Al-O reaction is the most common pathway to release limited energy while Al-F reaction has received much attentions to enhance Al combustion efficiency.However,microscopic understanding of the Al-O/Al-F reaction dynamics remains unsolved,which is fundamentally necessary to further improve Al combustion efficiency.In this work,for the first time,Al-O/Al-F reaction dynamic effects on the combustion of aluminum nanoparticles(n-Al)in oxygen/fluorine containing environments have been revealed via reactive molecular dynamics(RMD)simulations meshing together combustion experiments.Three RMD simulation systems of Al core/O_(2)/HF,n-Al/O_(2)/HF,and n-Al/O_(2)/CF4 with oxygen percentage ranging from 0%to 100%have been performed.The n-Al combustion in mixed O_(2)/CF_4 environments have been conducted by constant volume combustion experiments.RMD results show that Al-O reaction exhibits kinetic benefits while Al-F reaction owns thermodynamic benefits for n-Al combustion.In n-Al/O_(2)/HF,Al-O reaction gives faster energy release rate than Al-F reaction(1.1 times).The optimal energy release efficiency can be achieved with suitable oxygen percentage of 10%and 50%for n-Al/O_(2)/HF and n-Al/O_(2)/CF_4,respectively.In combustion experiments,90%of oxygen percentage can optimally enhance the peak pressure,pressurization rate and combustion heat.Importantly,Al-O reaction prefers to occur on the surface regions while Al-F reaction prefers to proceed in the interior regions of n-Al,confirming the kinetic/thermodynamic benefits of Al-O/Al-F reactions.The synergistic effect of Al-O/Al-F reaction for greatly enhancing n-Al combustion efficiency is demonstrated at atomicscale,which is beneficial for optimizing the combustion performance of metallic fuel.展开更多
In search of natural renewable resource-based bioactive molecules,20 hydroxamate inhibitors were designed and synthesized using cinamaldehyde as the starting material.Their structures were characterized by FT-IR,^(1)H...In search of natural renewable resource-based bioactive molecules,20 hydroxamate inhibitors were designed and synthesized using cinamaldehyde as the starting material.Their structures were characterized by FT-IR,^(1)HNMR,^(13)C NMR,and HRMS.And in vitro antifungal activity of the target compounds against 8 tested fungi was preliminarily evaluated by the agar dilution method.The bioassay results revealed that at the concentration of 50 mg/L,the target compounds exhibited certain inhibitory activity against 8 tested fungi,in which compounds 5r(R=o,o-Cl),5c(R=m-F),5b(R=o-F)and 5p(R=o,p-Cl)displayed better inhibitory activity of 93.3%,76.8%,75.3%and 72.3%,respectively,against P.piricola than that of the positive control chlorothalonil.At the same time,3D-quantitative structure-activity relationship(3D-QSAR)study was carried out to explore the relationship of the molecular structures with their antifungal activity against P.piricola.And a reasonable and effective 3D-QSAR model(r^(2)=0.980,q^(2)=0.501)has been established.Besides,molecular docking was also performed to reveal the binding mode of the target compound 5r(R=o,o-Cl)with succinate dehydrogenase(SDH).It was found that compound 5r could be well embedded in the active pocket of the receptor protein.This showed a similar mode with SDH inhibitors(SDHI)carboxin.展开更多
This study has examined the structure and function of the biliverdin reductase A (BLVRA) gene and its correlation with the green eggshell character in Jinyun ducks. The previously unknown sequences of 3' and 5'...This study has examined the structure and function of the biliverdin reductase A (BLVRA) gene and its correlation with the green eggshell character in Jinyun ducks. The previously unknown sequences of 3' and 5' ends of duck BLVRA mRNA were cloned, using RT-PCR and 5' RACE methods with four pairs of primers designed from the known coding sequence (CDS) of the duck BLVRA gene. Gene expression levels of BLVRA in the shell gland were quantified by real-time PCR, and eggshell colors were determined objectively by the reflection coefficient. The cDNA sequence of BLVRA was comprised of 1071 nucleotides, encoding a protein of 303 amino acids with an isoelectric point of 7.15 and molecular weight of 34.3 kDa. The 5' and 3' ends of the duck BLVRA gene sequence published in the GenBank were extended by 238 and 199 bp, respectively. The deduced amino acid sequence of duck BLVRA had 95.3% identity with Gallus gallus, 95.0% with Taeniopygia guttata, 70.0% with Xenopus tropicalis,61.1% with Bos taurus, 60.5% with Homo sapiens and 59.5% with Mus musculus, which indicated that the BLVRA gene was evolutionarily conserved. The relative gene expression level of BLVRA in shell glands of Jinyun ducks with white eggshells was 3 times higher than that in ducks with dark green eggshells (P<0.01). There was a significant positive correlation between reflection coefficient of eggshells and the relative expression of the BLVRA gene (r=0.719, P<0.05). Together, these findings suggest that the BLVRA gene could be a candidate gene for the molecule breeding of ducks with green eggshells.展开更多
In order to research the feasibility of using the selective adsorption principle to achieve automatic shaping of nano patterns,in this study,using the liquid gallium as the conductive ink and graphene as the printing ...In order to research the feasibility of using the selective adsorption principle to achieve automatic shaping of nano patterns,in this study,using the liquid gallium as the conductive ink and graphene as the printing plate surface,by changing the surface wettability of patterned areas on the nanoscale of graphene printed boards,the automatic formation of liquid gallium patterns on the graphene printed plate surface was simulated.The results indicated that liquid gallium can achieve automatic patterning on the surface of graphene patterned areas;the greater the interaction energy between gallium and carbon atoms,the clearer the pattern;gallium liquid is prone to remain in complex local positions of the pattern,making it difficult to shape the pattern;if the spacing between adjacent pattern lines is too large or too small,it will result in residual gallium liquid between the lines;increasing the thickness of the gallium film will cause the pattern to expand beyond the boundary,but increasing the thickness of the gallium film can also enhance the thickness and uniformity of the pattern lines.In summary,the principle of selective adsorption can be used to achieve the automatic formation of nano patterns,and the pattern formation effect is influenced by factors such as atomic interaction energy and pattern configuration.展开更多
As the simplest hydrogen-bonded alcohol,liquid methanol has attracted intensive experimental and theoretical interest.However,theoretical investigations on this system have primarily relied on empirical intermolecular...As the simplest hydrogen-bonded alcohol,liquid methanol has attracted intensive experimental and theoretical interest.However,theoretical investigations on this system have primarily relied on empirical intermolecular force fields or ab initio molecular dynamics with semilocal density functionals.Inspired by recent studies on bulk water using increasingly accurate machine learning force fields,we report a new machine learning force field for liquid methanol with a hybrid functional revPBE0 plus dispersion correction.Molecular dynamics simulations on this machine learning force field are orders of magnitude faster than ab initio molecular dynamics simulations,yielding the radial distribution functions,selfdiffusion coefficients,and hydrogen bond network properties with very small statistical errors.The resulting structural and dynamical properties are compared well with the experimental data,demonstrating the superior accuracy of this machine learning force field.This work represents a successful step toward a first-principles description of this benchmark system and showcases the general applicability of the machine learning force field in studying liquid systems.展开更多
Limited charge carrier lifetime(τ)leads to the short charge carrier diffusion length(L_(D))and thus impedes the improvement of power conversion efficiencies(PCEs)of organic solar cells(OSCs).Herein,anthracene(AN)as t...Limited charge carrier lifetime(τ)leads to the short charge carrier diffusion length(L_(D))and thus impedes the improvement of power conversion efficiencies(PCEs)of organic solar cells(OSCs).Herein,anthracene(AN)as the additive is introduced into classical donor:acceptor pairs to increase theτ.Introducing AN efficiently enhances the crystallinity of the PM 6:BTP-eC 9+blend film to reduce the trap density and increase theτto 1.484μs,achieving the prolonged L_(D).The prolonged L_(D) enables the PM 6:BTP-eC 9+blend film to gain weaker charge carrier recombination,reduced leakage current,and shorter charge carrier extraction time in devices,compared with PM 6:BTP-eC 9 counterparts.Therefore,PM 6:BTP-eC 9+based OSCs achieve higher PCEs of 18.41%±0.16%than PM 6:BTP-eC 9 based ones(17.08%±0.11%).Moreover,the PM 6:L 8-BO+based OSC presents an impressive PCE of 19.14%.It demonstrates that introducing AN is an efficient method to increase theτfor prolonged L_(D),boosting PCEs of OSCs.展开更多
文摘The no-cloning theorem has sparked considerable interest in achieving high-fidelity approximate quantum cloning.Most of the previous studies mainly focused on the cloning of single particle states,and cloning schemes used there are incapable of cloning quantum entangled states in multipartite systems.Few schemes were proposed for cloning multiparticle states,which consume more entanglement resources with loss of qubits,and the fidelity of the cloned state is relatively low.In this paper,cloning schemes for bipartite and tripartite entangled states based on photonic quantum walk and entanglement swapping are proposed.The results show that according to the proposed schemes,two high-fidelity(up to 0.75)cloned states can be obtained with less quantum resource consumption.Because of the simple cloning steps,few quantum resources and high fidelity,these schemes are both efficient and feasible.Moreover,this cloning machine eliminates the need for tracing out cloning machine,thereby minimizing resource waste.
文摘Since the discovery of carbon dots(CDs)in 2004,the unique photoluminescence phenomenon of CDs has attracted widespread attention.However,the molecular weight of CDs has not been adequately quantified at present,due to CDs are atomically imprecise and their molecular weight distribution is broad.In this paper,a series of Pluronic-modified CDs were prepared and the structure of the CDs was briefly analyzed.Subsequently,a molecular weight measurement method based on colligative properties was developed,and the correction coefficient in the algorithm was briefly analyzed.The calculated molecular weight was applied to the determination of surface adsorption capacity.This work provided a method for averaging the molecular weight of atomically imprecise particulate materials,which is expected to provide new opportunities in related fields.
文摘High-quality antiferromagnetic(AFM)θ-phase manganese nitride(MnN)films were successfully grown on MgO(001)substrates by plasma-assisted molecular beam epitaxy.Structural analysis confirms the high-quality MnN film has a tetragonal distortion with a c/a ratio of~0.98.The film exhibits exceptional stability in both aqueous and ambient conditions,which is a crucial factor for practical applications.Electrical transport reveals its metallic behavior with an upturn at low temperatures,which could be attributed to the Kondo effect originated from nitrogen vacancy-induced magnetic impurities.Room temperature exchange bias has been demonstrated in a MnN/CoFeB heterostructure,verifying the AFM ordering of MnN.Considering its high Néel temperature~650 K,superior stability,and low-cost,this work highlights the epitaxial MnN films as a promising candidate for AFM spintronic applications.
基金Supported by the Natural Science Basic Research Program of Shaanxi Province(2023-JC-QN-0758)Shaanxi University of Science and Technology Research Launch Project(2020BJ-26)Doctoral Research Initializing Fund of Hebei University of Science and Technology,China(1181476).
文摘This paper discusses the influence of Sb/In ratio on the transport properties and crystal quality of the 200 nm InAs_(x)Sb_(1-x)thin film.The Sb content of InAs_(x)Sb_(1-x)thin film in all samples was verified by HRXRD of the symmetrical 004 reflections and asymmetrical 115 reflections.The calculation results show that the Sb component was 0.6 in the InAs_(x)Sb_(1-x)thin film grown under the conditions of Sb/In ratio of 6 and As/In ratio of 3,which has the highest electron mobility(28560 cm^(2)/V·s)at 300 K.At the same time,the influence ofⅤ/Ⅲratio on the transport properties and crystal quality of Al_(0.2)In_(0.8)Sb/InAs_(x)Sb_(1-x)quantum well heterostructures also has been investigated.As a result,the Al_(0.2)In_(0.8)Sb/InAs_(0.4)Sb_(0.6)quantum well heterostructure with a channel thickness of 30 nm grown under the conditions of Sb/In ratio of 6 and As/In ratio of 3 has a maximum electron mobility of 28300 cm^(2)/V·s and a minimum RMS roughness of 0.68 nm.Through optimizing the growth conditions,our samples have higher electron mobility and smoother surface morphology.
基金Supported by Natural Science Foundation of Heilongjiang Province (C2007-7)Scientific and Technical Innovation Fund of Harbin (RC2006QN002027)Northeast Agricultural University Research Fund (2005)
文摘Chitin is the most widespread amino polysaccharide in nature. Chitin synthase （CHS） plays an important role in chitin formation in the cuticle and the peritrophic membrane （PM） lining the midgut. Total RNA was isolated from the cuticle of Mamestra brassicae （L.） fourth instar larva, cDNA sequence was cloned by RT-PCR and Rapid Amplification of cDNA Ends （RACE）. cDNA 5 220 bp in length, contained an open reading frame of 4 704 bp coding for a polypeptide of 1 567 amino acid residues with a predicted molecular weight of 178.3 ku and its pI was 6.42. The deduced amino acid sequence from Mi brassicae （L.） shared the high level of identity with chitin synthase sequences from other insects, especially lepidopteran insects, cDNA sequence has been deposited with GenBank under accession No. GQ281761
文摘Sea Island cotton(Gossypium barbadense L.) has been highly valued in Verticillium wilt resistance and many fiber qualities including fiber length,strength,and fineness.To identify whether
文摘Verticillium dahliae Kleb.is a necrotrophic plant pathogen which causes serious soil borne vascular disease in cotton.The molecular basis the defense response of cotton to this pathogen is
文摘CAP,an adenylyl cyclase-associated protein,is predicted to be involved in cytoskeletal organization and signal transduction.Recently,we found that CAP may play an important role in fuzz-like fiber cell initiation in cotton.For the further research,we isolated two CAP homologues from wild
文摘Studies on the cold-responsive genes and cold signaling of woody species drop far behind in comparison to herbaceous plants.Due to similar lignified structure,perennial characteristic,and enhanced tolerance,it seems much easier to find strongly antifreeze genes and obtain effective results in transgenic woody plants.In this study,Ammopiptanthus mongolicus,an evergreen,broadleaf and cold-resist leguminous shrub growing in the desert of Inner Mongolia,was used as a material for low-temperature induced gene isolation.Through differential expression analysis induced by low-temperature,thirteen up-regulated cDNAs were identified.One of them,AmEBP1,(accession number:DQ519359)confers enhanced cold-tolerance to both transgenic E.coli and transgenic Arabidopsis.Results suggest that AmEBP1 can stimulate the synthesis of ribosome and the dephosphyration of the α-subunit of initiation factor 2(eIF2α),and subsequently promote the translation process.By which the transgenic plants obtained increased cold-resistant ability.
文摘The zinc finger proteins belong to the largest family of transcription factors.But there is little research of Cys2/His2 type zinc finger proteins in cotton,and there is no submission of correlating
基金Supported by the National Natural Science Foundation of China(32272724)the National Science Foundation of Heilongjiang Province,China(LH2019C033)。
文摘At the early stage,the transcriptome sequencing technique was used to detect the differentially expressed gene CsFK111 between vine cucumber and dwarf cucumber D0462.The gene was cloned,and bioinformatics software tools were used to analyze and predict the gene family and this gene.There were 30 members of the cucumber F-box gene family.The coding region of the cucumber CsFK111 gene was full-length 1314 bp,which encoded 437 amino acids and was predicted to be located in the nucleus.The protein encoded by this gene was a non-transmembrane protein,and the prediction of the secondary structure showed thatβ-lamellar structure and irregular crimp were dominant.A comparison of the phylogenetic tree showed that it was closest to cantaloupe and belonged to the same branch.The results provided a basis for future study on the regulation mechanism of the CsFK111 gene on cucumber dwarfing and also laid a foundation for further study of FBK family proteins.
文摘In this study,circular dichroism(CD)and molecular dynamics(MD)simulation were used to investigate the thermal unfolding pathway of staphylococcal enterotoxin B(SEB)at temperatures of 298–371 and 298–500 K,and the relationship between the experimental and simulation results were explored.Our computational findings on the secondary structure of SEB showed that at room temperature,the CD spectroscopic results were highly consistent with the MD results.Moreover,under heating conditions,the changing trends of helix,sheet and random coil obtained by CD spectral fitting were highly consistent with those obtained by MD.In order to gain a deeper understanding of the thermal stability mechanism of SEB,the MD trajectories were analyzed in terms of root mean square deviation(RMSD),secondary structure assignment(SSA),radius of gyration(R_(g)),free energy surfaces(FES),solvent-accessible surface area(SASA),hydrogen bonds and salt bridges.The results showed that at low heating temperature,domain Ⅰ without loops(omitting the mobile loop region)mainly relied on hydrophobic interaction to maintain its thermal stability,whereas the thermal stability of domain Ⅱ was mainly controlled by salt bridges and hydrogen bonds.Under high heating temperature conditions,the hydrophobic interactions in domain Ⅰ without loops were destroyed and the secondary structure was almost completely lost,while domain Ⅱ could still rely on salt bridges as molecular staples to barely maintain the stability of the secondary structure.These results help us to understand the thermodynamic and kinetic mechanisms that maintain the thermal stability of SEB at the molecular level,and provide a direction for establishing safer and more effective food sterilization processes.
基金supported by Scientific Research Fund of Sichuan Province Education Department(No.09ZA073)Sichuan Provincial Technology Support Project(No.2011NZ0003)
文摘The objective of the present study was to investigate the developmental expression patterns of Insulin-like growth factor-binding protein 1 (IGFBP-1) gene in different tissues of postnatal Nanjiang Mongolian Gazelles. Samples of heart, liver, spleen, lung, longissimus dorsi, semimembranosus, m. triceps brachii and biceps muscle of thigh were collected from a total of 36 Nanjiang Mongolian Gazelles at the age of 0, 15, 30, 60, 90 and 120 days after birth (3 males and 3 females at each age). The CDS was sequenced and ontogeny of mRNA levels of IGFBP-1 were measured by real-time fluorescence quantitative RT-PCR. The size of IGFBP-1 ORF was 792 bp encoding 263 amino acid residues, and displayed higher nucleotide/amino acid sequence identities with other ruminants compared to non-ruminants. The levels of IGFBP-1 mRNA in liver were highest (P<0.01), levels were medium in lung, spleen and heart, and the lowest in the muscles; there were no significant differences among the muscles (P>0.05). Three expression patterns of IGFBP-1 mRNA during postnatal growth from birth to day 60 were found: consistently decreasing (liver), fluctuating as increasing then decreasing (heart) or as decreasing then increasing then decreasing (spleen, lung and muscles). The results indicate that the IGFBP-1 gene is highly conserved among species, and liver has the highest expression. It was concluded that IGFBP-1 plays important roles in early postnatal growth and is expressed in a developmental-tissue-dependent manner.
基金support by the National Natural Science Foundation of China(NSFC,Grant Nos.12002324,12372341,12172342)。
文摘Improving the energy conversion efficiency in metallic fuel(e.g.,Al)combustion is always desirable but challenging,which often involves redox reactions of aluminum(Al)with various mixed oxidizing environments.For instance,Al-O reaction is the most common pathway to release limited energy while Al-F reaction has received much attentions to enhance Al combustion efficiency.However,microscopic understanding of the Al-O/Al-F reaction dynamics remains unsolved,which is fundamentally necessary to further improve Al combustion efficiency.In this work,for the first time,Al-O/Al-F reaction dynamic effects on the combustion of aluminum nanoparticles(n-Al)in oxygen/fluorine containing environments have been revealed via reactive molecular dynamics(RMD)simulations meshing together combustion experiments.Three RMD simulation systems of Al core/O_(2)/HF,n-Al/O_(2)/HF,and n-Al/O_(2)/CF4 with oxygen percentage ranging from 0%to 100%have been performed.The n-Al combustion in mixed O_(2)/CF_4 environments have been conducted by constant volume combustion experiments.RMD results show that Al-O reaction exhibits kinetic benefits while Al-F reaction owns thermodynamic benefits for n-Al combustion.In n-Al/O_(2)/HF,Al-O reaction gives faster energy release rate than Al-F reaction(1.1 times).The optimal energy release efficiency can be achieved with suitable oxygen percentage of 10%and 50%for n-Al/O_(2)/HF and n-Al/O_(2)/CF_4,respectively.In combustion experiments,90%of oxygen percentage can optimally enhance the peak pressure,pressurization rate and combustion heat.Importantly,Al-O reaction prefers to occur on the surface regions while Al-F reaction prefers to proceed in the interior regions of n-Al,confirming the kinetic/thermodynamic benefits of Al-O/Al-F reactions.The synergistic effect of Al-O/Al-F reaction for greatly enhancing n-Al combustion efficiency is demonstrated at atomicscale,which is beneficial for optimizing the combustion performance of metallic fuel.
文摘In search of natural renewable resource-based bioactive molecules,20 hydroxamate inhibitors were designed and synthesized using cinamaldehyde as the starting material.Their structures were characterized by FT-IR,^(1)HNMR,^(13)C NMR,and HRMS.And in vitro antifungal activity of the target compounds against 8 tested fungi was preliminarily evaluated by the agar dilution method.The bioassay results revealed that at the concentration of 50 mg/L,the target compounds exhibited certain inhibitory activity against 8 tested fungi,in which compounds 5r(R=o,o-Cl),5c(R=m-F),5b(R=o-F)and 5p(R=o,p-Cl)displayed better inhibitory activity of 93.3%,76.8%,75.3%and 72.3%,respectively,against P.piricola than that of the positive control chlorothalonil.At the same time,3D-quantitative structure-activity relationship(3D-QSAR)study was carried out to explore the relationship of the molecular structures with their antifungal activity against P.piricola.And a reasonable and effective 3D-QSAR model(r^(2)=0.980,q^(2)=0.501)has been established.Besides,molecular docking was also performed to reveal the binding mode of the target compound 5r(R=o,o-Cl)with succinate dehydrogenase(SDH).It was found that compound 5r could be well embedded in the active pocket of the receptor protein.This showed a similar mode with SDH inhibitors(SDHI)carboxin.
文摘This study has examined the structure and function of the biliverdin reductase A (BLVRA) gene and its correlation with the green eggshell character in Jinyun ducks. The previously unknown sequences of 3' and 5' ends of duck BLVRA mRNA were cloned, using RT-PCR and 5' RACE methods with four pairs of primers designed from the known coding sequence (CDS) of the duck BLVRA gene. Gene expression levels of BLVRA in the shell gland were quantified by real-time PCR, and eggshell colors were determined objectively by the reflection coefficient. The cDNA sequence of BLVRA was comprised of 1071 nucleotides, encoding a protein of 303 amino acids with an isoelectric point of 7.15 and molecular weight of 34.3 kDa. The 5' and 3' ends of the duck BLVRA gene sequence published in the GenBank were extended by 238 and 199 bp, respectively. The deduced amino acid sequence of duck BLVRA had 95.3% identity with Gallus gallus, 95.0% with Taeniopygia guttata, 70.0% with Xenopus tropicalis,61.1% with Bos taurus, 60.5% with Homo sapiens and 59.5% with Mus musculus, which indicated that the BLVRA gene was evolutionarily conserved. The relative gene expression level of BLVRA in shell glands of Jinyun ducks with white eggshells was 3 times higher than that in ducks with dark green eggshells (P<0.01). There was a significant positive correlation between reflection coefficient of eggshells and the relative expression of the BLVRA gene (r=0.719, P<0.05). Together, these findings suggest that the BLVRA gene could be a candidate gene for the molecule breeding of ducks with green eggshells.
文摘In order to research the feasibility of using the selective adsorption principle to achieve automatic shaping of nano patterns,in this study,using the liquid gallium as the conductive ink and graphene as the printing plate surface,by changing the surface wettability of patterned areas on the nanoscale of graphene printed boards,the automatic formation of liquid gallium patterns on the graphene printed plate surface was simulated.The results indicated that liquid gallium can achieve automatic patterning on the surface of graphene patterned areas;the greater the interaction energy between gallium and carbon atoms,the clearer the pattern;gallium liquid is prone to remain in complex local positions of the pattern,making it difficult to shape the pattern;if the spacing between adjacent pattern lines is too large or too small,it will result in residual gallium liquid between the lines;increasing the thickness of the gallium film will cause the pattern to expand beyond the boundary,but increasing the thickness of the gallium film can also enhance the thickness and uniformity of the pattern lines.In summary,the principle of selective adsorption can be used to achieve the automatic formation of nano patterns,and the pattern formation effect is influenced by factors such as atomic interaction energy and pattern configuration.
基金supported by the CAS Project for Young Scientists in Basic Research(YSBR-005)the National Natural Science Foundation of China(22325304,22221003 and 22033007)We acknowledge the Supercomputing Center of USTC,Hefei Advanced Computing Center,Beijing PARATERA Tech Co.,Ltd.,for providing high-performance computing services。
文摘As the simplest hydrogen-bonded alcohol,liquid methanol has attracted intensive experimental and theoretical interest.However,theoretical investigations on this system have primarily relied on empirical intermolecular force fields or ab initio molecular dynamics with semilocal density functionals.Inspired by recent studies on bulk water using increasingly accurate machine learning force fields,we report a new machine learning force field for liquid methanol with a hybrid functional revPBE0 plus dispersion correction.Molecular dynamics simulations on this machine learning force field are orders of magnitude faster than ab initio molecular dynamics simulations,yielding the radial distribution functions,selfdiffusion coefficients,and hydrogen bond network properties with very small statistical errors.The resulting structural and dynamical properties are compared well with the experimental data,demonstrating the superior accuracy of this machine learning force field.This work represents a successful step toward a first-principles description of this benchmark system and showcases the general applicability of the machine learning force field in studying liquid systems.
基金Projects(52272056,52372056,52232003)supported by the National Natural Science Foundation of ChinaProject(2023RC3044)supported by the Science and Technology Innovation Program of Hunan Province,China。
文摘Limited charge carrier lifetime(τ)leads to the short charge carrier diffusion length(L_(D))and thus impedes the improvement of power conversion efficiencies(PCEs)of organic solar cells(OSCs).Herein,anthracene(AN)as the additive is introduced into classical donor:acceptor pairs to increase theτ.Introducing AN efficiently enhances the crystallinity of the PM 6:BTP-eC 9+blend film to reduce the trap density and increase theτto 1.484μs,achieving the prolonged L_(D).The prolonged L_(D) enables the PM 6:BTP-eC 9+blend film to gain weaker charge carrier recombination,reduced leakage current,and shorter charge carrier extraction time in devices,compared with PM 6:BTP-eC 9 counterparts.Therefore,PM 6:BTP-eC 9+based OSCs achieve higher PCEs of 18.41%±0.16%than PM 6:BTP-eC 9 based ones(17.08%±0.11%).Moreover,the PM 6:L 8-BO+based OSC presents an impressive PCE of 19.14%.It demonstrates that introducing AN is an efficient method to increase theτfor prolonged L_(D),boosting PCEs of OSCs.
