Genetic improvement of drought resistance is one of the main breeding goals for common bean,so molecular markers must be identified to facilitate drought resistance breeding.In this study,we evaluated the proline,treh...Genetic improvement of drought resistance is one of the main breeding goals for common bean,so molecular markers must be identified to facilitate drought resistance breeding.In this study,we evaluated the proline,trehalose,raffinose,and stachyose contents of 210 common bean accessions under two watering conditions and found large variations in all four.The coefficients of variation ranged from 21.21%for proline content to 78.69%for stachyose content under well-watered conditions,and from 20.11%for proline content to 50.08%for trehalose content under drought stress.According to our genome-wide association analysis,32 quantitative trait loci were associated with drought resistance,seven of which overlapped with known loci.Four hotspot regions were identified at Pv01,Pv07 and Pv11.A set of candidate genes was identified,including genes encoding MYB,bZIP,bHLH,ERF,and protein kinases.Among these genes,Phvul.001G189400,Phvul.007G273000 and Phvul.008G270500 were annotated as bZIP,ERF and WRKY,respectively.These genes are reportedly involved in drought stress responses in Arabidopsis thaliana and were induced by drought stress in common bean.Significant SNPs in six candidate gene regions formed different haplotypes,and phenotypic analysis revealed significant differences among the haplotypes.These results provide new insight into the genetic basis of drought resistance in common bean and reveal candidate genes and superior natural variations that will be useful for improving common bean.展开更多
Drought stress severely impairs common bean production.For facilitating drought-resistance breeding in common bean,molecular markers were identified in a genome-wide level marker–trait association study.A panel of 21...Drought stress severely impairs common bean production.For facilitating drought-resistance breeding in common bean,molecular markers were identified in a genome-wide level marker–trait association study.A panel of 210 common bean accessions showed large variation in 11 agronomic traits at the adult stage(plant height,pod number per plant,seed number per pod,seed number per plant,seed yield per plant,pod length,harvest index,pod harvest index,days to maturity,hundred-seed weight,and seed yield)under two water conditions.The coefficient of variation ranged from 6.21% for pod harvest index to51.00% for seed number per plant under well-watered conditions,and from 4.05% for days to maturity to 40.72% for seed number per plant under drought stress.In a genome-wide association study,119quantitative-trait loci were associated with drought resistance,including 41 adjacent to known loci.Among these loci,12 were found to be associated with at least two traits.Three major loci were identified at Pv01 and Pv02.A set of candidate genes were found that encode MYBs,AREBs,WKRYs,and protein kinases.These results reveal promising alleles that control drought resistance,shedding light on the genetic basis of drought resistance and accelerating future efforts for drought resistance improvement in common bean.展开更多
Coal is the dominant energy source in China,and coal-fired power accounts for about half of coal consumption.However,air pollutant emissions from coal-fired power plants cause severe ecological and environmental probl...Coal is the dominant energy source in China,and coal-fired power accounts for about half of coal consumption.However,air pollutant emissions from coal-fired power plants cause severe ecological and environmental problems.This paper focuses on near-zero emission technologies and applications for clean coal-fired power.The long-term operation states of near-zero emission units were evaluated,and synergistic and special mercury(Hg)control technologies were researched.The results show that the principle technical route of near-zero emission,which was applied to 101 of China’s coal-fired units,has good adaptability to coal properties.The emission concentrations of particulate matter(PM),SO2,and NOx were below the emission limits of gas-fired power plants and the compliance rates of the hourly average emission concentrations reaching near-zero emission in long-term operation exceeded 99%.With the application of near-zero emission technologies,the generating costs increased by about 0.01 CNY∙(kW∙h)-1.However,the total emissions of air pollutants decreased by about 90%,resulting in effective improvement of the ambient air quality.Furthermore,while the Hg emission concentrations of the near-zero emission units ranged from 0.51 to 2.89μg∙m^-3,after the modified fly ash(MFA)special Hg removal system was applied,Hg emission concentration reached as low as 0.29μg∙m^-3.The operating cost of this system was only 10%-15%of the cost of mainstream Hg removal technology using activated carbon injection.Based on experimental studies carried out in a 50000 m^3∙h^-1 coal-fired flue gas pollutant control pilot platform,the interaction relationships of multi-pollutant removal were obtained and solutions were developed for emissions reaching different limits.A combined demonstration application for clean coal-fired power,with the new“1123”eco-friendly emission limits of 1,10,20 mg∙m^-3,and 3μg∙m^-3,respectively,for PM,SO2,NOx,and Hg from near-zero emission coal-fired power were put forward and realized,providing engineering and technical support for the national enhanced pollution emission standards.展开更多
As a typical compatible solute, proline is accumulated in plants under environmental stresses. Proline transporter(Pro T) plays an important role in proline distribution between plant organs. Using a candidate gene ap...As a typical compatible solute, proline is accumulated in plants under environmental stresses. Proline transporter(Pro T) plays an important role in proline distribution between plant organs. Using a candidate gene approach, we cloned a c DNA sequence for Pro T from common bean(Phaseolus vulgaris L.) and designated the gene Pv Pro T. The deduced amino acid sequence of Pv Pro T showed high similarity to Bet/Pro T proteins from other leguminous plants, and the highest similarity was observed with mothbean(Vigna aconitifolia L.) Vu Pro T.Relative quantification of the m RNA level of Pv Pro T using real-time PCR analysis showed that the Pv Pro T transcript level was higher in leaves than in stems and roots of common bean plants subjected to drought and salt stress. Under 20%(w/w) PEG-6000 treatment,drought-resistant plants expressed a higher level of Pv Pro T transcripts than droughtsensitive plants. Although heterologous expression of Pv Pro T in the Escherichia coli mutant mkh13 showed that Pv Pro T exhibited uptake activities for proline and betaine, no betaine content was detected in the common bean. These findings suggest that Pv Pro T plays an important role in the transportation of proline in common bean plants exposed to drought and salt stress.展开更多
The ultrahigh vacuum scanning tunneling microscope(STM)was used to characterize the GaSb_(1-x)Bi_(x) films of a few nanometers thickness grown by the molecular beam epitaxy(MBE)on the GaSb buffer layer of 100 nm with ...The ultrahigh vacuum scanning tunneling microscope(STM)was used to characterize the GaSb_(1-x)Bi_(x) films of a few nanometers thickness grown by the molecular beam epitaxy(MBE)on the GaSb buffer layer of 100 nm with the GaSb(100)substrates.The thickness of the GaSb_(1-x)Bi_(x) layers of the samples are 5 and 10 nm,respectively.For comparison,the GaSb buffer was also characterized and its STM image displays terraces whose surfaces are basically atomically flat and their roughness is generally less than 1 monolayer(ML).The surface of 5 nm GaSb_(1-x)Bi_(x) film reserves the same terraced morphology as the buffer layer.In contrast,the morphology of the 10 nm GaSb_(1-x)Bi_(x) film changes to the mound-like island structures with a height of a few MLs.The result implies the growth mode transition from the two-dimensional mode as displayed by the 5 nm film to the Stranski-Krastinov mode as displayed by the 10 nm film.The statistical analysis with the scanning tunneling spectroscopy(STS)measurements indicates that both the incorporation and the inhomogeneity of Bi atoms increase with the thickness of the GaSb_(1-x)Bi_(x) layer.展开更多
This special issue is focused on grain legumes,which belong to the Fabaceae family.Legumes are the second largest family of plants in the world after the grasses and are key components of manmade and natural ecosystem...This special issue is focused on grain legumes,which belong to the Fabaceae family.Legumes are the second largest family of plants in the world after the grasses and are key components of manmade and natural ecosystems[1–3].They provide the environmental service of nitrogen fixation,so essential to soil construction and fertility maintenance,and are thus essential to agricultural systems[4,5].Different species of legumes range from huge trees to shrubs展开更多
Common bacterial blight(CBB), caused by Xanthomonas axonopodis pv. phaseoli and Xanthomonas fuscans subsp. fuscans(Xff), is a worldwide disease of common bean(Phaseolus vulgaris L.).Longyundou 5, a Chinese cultivar in...Common bacterial blight(CBB), caused by Xanthomonas axonopodis pv. phaseoli and Xanthomonas fuscans subsp. fuscans(Xff), is a worldwide disease of common bean(Phaseolus vulgaris L.).Longyundou 5, a Chinese cultivar in the Mesoamerican gene pool of common bean, displays resistance to the Xff strain XSC3-1. To identify the genetic mechanisms behind this resistance,we crossed Long 5 with a susceptible genotype to develop a mapping population of F2 plants.Plant resistance to CBB was identified at 14 and 21 days after inoculation with Xff strain XSC3-1.A major QTL at 14 and 21 days after inoculation was mapped on chromosome Pv10 with LOD scores of 6.41 and 5.35, respectively. This locus was associated with SAP6, a previouslyidentified and much-used dominant marker, but in a 4.2 cM interval between new codominant markers BMp10s174 and BMp10s244. Ten candidate genes were found between markers BMp10s174 and BMp10s244 on chromosome Pv10 and could encode defense response proteins responding to CBB pathogens. Four pairs each of epistatic QTL for CBB resistance were detected at 14 and 21 days after inoculation. Phenotypic variation explained by the epistatic QTL ranged from 7.19% to 12.15% and 7.72% to 8.80% at 14 and 21 days after inoculation, respectively. These results confirmed the importance of epistasis in CBB resistance in common bean. The adjacent markers found may be more efficient for marker assisted selection in common bean breeding for CBB resistance owing to their closer linkage to the target QTL.展开更多
InAs/GaSb type-II superlattce (T2SL) photodetector structures at the MWIR regime were grown by molecular beam epitaxy. The growth temperature and group-V soaking times were optimized with respect to interface and tran...InAs/GaSb type-II superlattce (T2SL) photodetector structures at the MWIR regime were grown by molecular beam epitaxy. The growth temperature and group-V soaking times were optimized with respect to interface and transport quality. Novel strain compensation schemes with insertion of InSb layers were proposed and tested to be efficient to tune the overall strain between tensile and compressive without degradation of interface and optical quality. The effect of the proposed methods is modeled by analytic functions.? Band structure calculations were also carried out for the proposed T2SL structures to assist optimizing sample designs. Single pixel photodiodes with a low dark current were demonstrated.展开更多
Optical gains of type-Ⅱ In Ga As/Ga As Bi quantum wells(QWs) with W, N, and M shapes are analyzed theoretically for near-infrared laser applications. The bandgap and wave functions are calculated using the self-con...Optical gains of type-Ⅱ In Ga As/Ga As Bi quantum wells(QWs) with W, N, and M shapes are analyzed theoretically for near-infrared laser applications. The bandgap and wave functions are calculated using the self-consistent k·p Hamiltonian, taking into account valence band mixing and the strain effect. Our calculations show that the M-shaped type-Ⅱ QWs are a promising structure for making 1.3 um lasers at room temperature because they can easily be used to obtain 1.3 um for photoluminescence with a proper thickness and have large wave-function overlap for high optical gain.展开更多
Strain and stress were simulated using finite element method(FEM)for threeⅢ-V-on-Insulator(Ⅲ-VOI)structures,i.e.,InP/SiO2/Si,InP/Al2O3/SiO2/Si,and GaAs/Al2O3/SiO2/Si,fabricated by ion-slicing as the substrates for o...Strain and stress were simulated using finite element method(FEM)for threeⅢ-V-on-Insulator(Ⅲ-VOI)structures,i.e.,InP/SiO2/Si,InP/Al2O3/SiO2/Si,and GaAs/Al2O3/SiO2/Si,fabricated by ion-slicing as the substrates for optoelectronic devices on Si.The thermal strain/stress imposes no risk for optoelectronic structures grown on InPOI at a normal growth temperature using molecular beam epitaxy.Structures grown on GaAsOI are more dangerous than those on InPOI due to a limited critical thickness.The intermedia Al2O3 layer was intended to increase the adherence while it brings in the largest risk.The simulated results reveal thermal stress on Al2O3 over 1 GPa,which is much higher than its critical stress for interfacial fracture.InPOI without an Al2O3 layer is more suitable as the substrate for optoelectronic integration on Si.展开更多
The characteristics of highway transport and the application of information technology in highway transport service are combined; the information flows' promotion and substitution on highway transport are analyzed; a...The characteristics of highway transport and the application of information technology in highway transport service are combined; the information flows' promotion and substitution on highway transport are analyzed; and the highway transport development strategy based on information flow impact is proposed.展开更多
Photocatalytic CH_(4) coupling into high-valued C_(2)H_(6) is highly attractive,whereas the photosynthetic rate,especially under oxygen-free system,is still unsatisfying.Here,we designed the negatively charged metal s...Photocatalytic CH_(4) coupling into high-valued C_(2)H_(6) is highly attractive,whereas the photosynthetic rate,especially under oxygen-free system,is still unsatisfying.Here,we designed the negatively charged metal supported on metal oxide nanosheets to activate the inert C-H bond in CH_(4)and hence accelerate CH_(4) coupling performance.As an example,the synthetic Au/ZnO porous nanosheets exhibit the C_(2)H_(6) photosynthetic rate of 1,121.6μmol g^(-1)_(cat)h^(-1)and the CH_(4) conversion rate of 2,374.6μmol g^(-1)_(cat)h^(-1) under oxygen-free system,2 orders of magnitude higher than those of previously reported photocatalysts.By virtue of several in situ spectroscopic techniques,it is established that the generated Au^(δ-)and O^-species together polarized the C-H bond,while the Au^(δ-)and O^-species jointly stabilized the CH_(3) intermediates,which favored the coupling of CH_(3) intermediate to photosynthesize C_(2)H_(6) instead of overoxidation into CO_(x).Thus,the design of dual active species is beneficial for achieving high-efficient CH_(4)-to-C_(2)H_(6) photoconversion.展开更多
China has established the largest clean coal-fired power generation system in the world by accomplishing the technological transformation of coal-fired power plants(CFPPs)to achieve ultra-low emission.The potential fo...China has established the largest clean coal-fired power generation system in the world by accomplishing the technological transformation of coal-fired power plants(CFPPs)to achieve ultra-low emission.The potential for further particulate matter(PM)emission reduction to achieve near-zero emission for CFPPs has become a hotspot issue.In this study,PM emission from some ultra-low emission CFPPs adopting advanced air pollutant control technologies in China was reviewed.The results revealed that the average filterable particulate matter(FPM)concentration,measured as the total particulate matter(TPM)according to the current national monitoring standard,was(1.67±0.86)mg/m^(3),which could fully achieve the ultra-low emission standard for key regions(5 mg/m^(3)),but that achieving the near-zero emission standard was difficult(1 mg/m^(3)).However,the condensable particulate matter(CPM),with an average concentration of(1.06±1.28)mg/m^(3),was generally ignored during monitoring,which led to about 38.7%underestimation of the TPM.Even considering both FPM and CPM,the TPM emission from current CFPPs would contribute to less than 5%of atmospheric PM_(2.5) concentrations in the key cities and regions in China.Therefore,further reduction in FPM emission proposed by the near-zero emission plan of CFPPs may have less environmental benefit than emission control of other anthropogenic sources.However,it is suggested that the management of CPM emission should be strengthened,and a national standard for CPM emission monitoring based on the indirect dilution method should be established for CFPPs.Those measurements are helpful for optimal operation of air pollutant control devices and continuously promoting further emission reduction.展开更多
The development of efficient contrast agents for tumor-targeted imaging remains a critical challenge in the clinic.Herein,we proposed a tumor-derived extracellular vesicle(EV)-mediated targeting approach to improve in...The development of efficient contrast agents for tumor-targeted imaging remains a critical challenge in the clinic.Herein,we proposed a tumor-derived extracellular vesicle(EV)-mediated targeting approach to improve in vivo tumor imaging using ternary downconversion nanoparticles(DCNPs)with strong near infrared II(NIR-II)luminescence at 1,525 nm.The EVs were metabolically engineered with azide group,followed by in vivo labeling of DCNPs through copper-free click chemistry.By taking advantage of the homologous targeting property of tumor derived EVs,remarkable improvement in the tumor accumulation(6.5%injection dose(ID)/g)was achieved in the subcutaneous colorectal cancer model when compared to that of individual DCNPs via passive targeting(1.1%ID/g).Importantly,such bioorthogonal labeling significantly increased NIR-II luminescence signals and prolonged the retention at tumor sites.Our work demonstrates the great potential of EVs-mediated bioorthogonal approach for in vivo labeling of NIR-II optical probes,which provides a robust tool for tumor-specific imaging and targeted therapy.展开更多
Photocatalytic antibacterial approach shows great potential in treating multidrug-resistant bacterial infections.However,the bactericidal efficiency heavily depends on the photocatalytic activity of semiconductor mate...Photocatalytic antibacterial approach shows great potential in treating multidrug-resistant bacterial infections.However,the bactericidal efficiency heavily depends on the photocatalytic activity of semiconductor materials,which is limited by the fast recombination of photogenerated electron–hole pairs.Janus nano-heterostructures with spatial control growth of TiO_(2)nanoparticles(NPs)at one end of gold nanorods(Au NRs)are designed via surface ligand regulation for photocatalytic sterilization and infected wound healing.The asymmetric nanostructure of Janus gold nanorod-titanium dioxide nanoparticles(Janus AuNR-TiO_(2) NPs)promotes the directional migration of charge carriers and is more conducive to the spatial separation of electron–hole pairs.Moreover,the injection of hot electrons and enhancement of plasmon near-fields from the surface plasmon resonance(SPR)effect further improve the photocatalytic efficiency of Janus AuNR-TiO_(2) NPs.Under simulated sunlight irradiation,large amounts of reactive oxygen species(ROS)are generated for photocatalytic antibacterial activity.Enhanced bactericidal efficiency up to 99.99%against methicillin-resistant Staphylococcus aureus(MRSA)is achieved in vitro.Furthermore,Janus AuNR-TiO_(2) NPs exhibit superior biocompatibility,structural stability,and also remarkably accelerate MRSA-infected wound healing.Taking the above all into consideration,Janus AuNR-TiO_(2) NPs,as an efficient antibacterial photocatalyst,offers a promising strategy for MRSA infectious therapy.展开更多
Predator–prey interaction has long been an interesting item in the research of animal behaviors.Given that live prey can damage their predators,predators must trade foraging efficiency for safety while hunting,but th...Predator–prey interaction has long been an interesting item in the research of animal behaviors.Given that live prey can damage their predators,predators must trade foraging efficiency for safety while hunting,but the extent of this trade-off is not yet clear.Tiger beetles display diversity in their diets and hunting strategies,and hence,they become an ideal system to address how self-security affects foraging efficiency.We addressed this question in captive adult tiger beetles Cicindela gemmata.By offering several types of arthropod and plant foods,we confirmed that C.gemmata is carnivorous.We found that C.gemmata hunt by either ambushing or chasing their prey,and that they switch between strategies based on differences in the number of prey,the prey status and encounter rate,and the number of predators.Ambushing success increased with the number of prey but decreased with prey encounter rate.Chasing success decreased as prey body size and encounter rate increased.Foraging Cicindela gemmata often gave up an attack when it was nonfatal.This active giving up of hunting may be a consequence of a trade-off between foraging efficiency and self-security.Therefore,it is an adaptive response to the risk of injury when hunting for larger live prey.展开更多
Background:Previous studies have demonstrated the preclinical pharmacological and toxicological consistency,and clinical pharmacokinetic equivalence of bevacizumab biosimilar LY01008 with reference bevacizumab(Avastin...Background:Previous studies have demonstrated the preclinical pharmacological and toxicological consistency,and clinical pharmacokinetic equivalence of bevacizumab biosimilar LY01008 with reference bevacizumab(Avastin).This randomized controlled trial aimed to compare the efficacy and safety of LY01008 with Avastin in first-line treatment of Chinese patients with advanced or recurrent non-squamous non-small cell lung cancer(NSCLC).Methods:StageⅢB-ⅣNSCLC patients with evaluable lesions,good physical status,and adequate organ functions from 67 centers across China were randomized in a ratio of 1:1 to receive LY01008 or Avastin 15 mg/kg intravenously in combination with paclitaxel/carboplatin(combined treatment)for 4-6 cycles,followed by maintenance monotherapy with LY01008 until disease progression,intolerable toxicity,or death.The primary endpoint was objective response rate(ORR)in accordance with Response Evaluation Criteria in Solid Tumors(RECIST)version 1.1 confirmed by independent radiological review committees(IRRC).Secondary endpoints included disease control rate(DCR),duration of response(DoR),progression-free survival(PFS),overall survival(OS),and safety.This study was registered in Clinical Trials.gov(NCT03533127).Results:Between December 15^(th),2017,and May 15^(th),2019,a total of 649 patients were randomized to the LY01008(n=324)or Avastin(n=325)group.As of September 25th,2019 for primary endpoint analysis,589 patients received ORR evaluation,with a median number of combined treatment cycles of 5(range 1-6)andmedian duration of treatment of 3.0(range 0.0-5.1)months.ORRof responseevaluable patients in the LY01008 and Avastin groups were 48.5% and 53.0%,respectively.The stratified ORR ratio was 0.91(90%CI 0.80-1.04,within the prespecified equivalence margin of 0.75-1.33).Up to May 15^(th),2020,with a median follow-up of 13.6(range 0.8-28.4)months,no notable differences in DCR,median DoR,median PFS,median OS,and 1-year OS rate were observed between the LY01008 and Avastin groups.There were no clinically meaningful differences in safety and immunogenicity across treatment groups.Conclusions:LY01008 demonstrated similarity to Avastin in terms of efficacy and safety in Chinese patients with advanced or recurrent non-squamous NSCLC.LY01008 combined with paclitaxel/carboplatin is expected to become a new treatment option for unresectable,metastatic,LY01008 and Avastin groups.There were no clinically meaningful differences in safety and immunogenicity across treatment groups.Conclusions:LY01008 demonstrated similarity to Avastin in terms of efficacy and safety in Chinese patients with advanced or recurrent non-squamous NSCLC.LY01008 combined with paclitaxel/carboplatin is expected to become a new treatment option for unresectable,metastatic,or recurrent non-squamous NSCLC patients in the first-line setting.展开更多
基金supported by the National Key Research and Development Program of China(2019YFD1001300 and 2019YFD1001305)the Fundamental Research Funds for the Central Universities,China(SWUKQ22042)+1 种基金the China Agriculture Research System of MOF and MARA(CARS-08)the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences。
文摘Genetic improvement of drought resistance is one of the main breeding goals for common bean,so molecular markers must be identified to facilitate drought resistance breeding.In this study,we evaluated the proline,trehalose,raffinose,and stachyose contents of 210 common bean accessions under two watering conditions and found large variations in all four.The coefficients of variation ranged from 21.21%for proline content to 78.69%for stachyose content under well-watered conditions,and from 20.11%for proline content to 50.08%for trehalose content under drought stress.According to our genome-wide association analysis,32 quantitative trait loci were associated with drought resistance,seven of which overlapped with known loci.Four hotspot regions were identified at Pv01,Pv07 and Pv11.A set of candidate genes was identified,including genes encoding MYB,bZIP,bHLH,ERF,and protein kinases.Among these genes,Phvul.001G189400,Phvul.007G273000 and Phvul.008G270500 were annotated as bZIP,ERF and WRKY,respectively.These genes are reportedly involved in drought stress responses in Arabidopsis thaliana and were induced by drought stress in common bean.Significant SNPs in six candidate gene regions formed different haplotypes,and phenotypic analysis revealed significant differences among the haplotypes.These results provide new insight into the genetic basis of drought resistance in common bean and reveal candidate genes and superior natural variations that will be useful for improving common bean.
基金supported by the National Key Research and Development Program of China (2019YFD1001300,2019YFD1001305)the China Agriculture Research System of MOF and MARA-Food Legumes (CARS-08)the Agricultural Science and Technology Innovation Program of CAAS。
文摘Drought stress severely impairs common bean production.For facilitating drought-resistance breeding in common bean,molecular markers were identified in a genome-wide level marker–trait association study.A panel of 210 common bean accessions showed large variation in 11 agronomic traits at the adult stage(plant height,pod number per plant,seed number per pod,seed number per plant,seed yield per plant,pod length,harvest index,pod harvest index,days to maturity,hundred-seed weight,and seed yield)under two water conditions.The coefficient of variation ranged from 6.21% for pod harvest index to51.00% for seed number per plant under well-watered conditions,and from 4.05% for days to maturity to 40.72% for seed number per plant under drought stress.In a genome-wide association study,119quantitative-trait loci were associated with drought resistance,including 41 adjacent to known loci.Among these loci,12 were found to be associated with at least two traits.Three major loci were identified at Pv01 and Pv02.A set of candidate genes were found that encode MYBs,AREBs,WKRYs,and protein kinases.These results reveal promising alleles that control drought resistance,shedding light on the genetic basis of drought resistance and accelerating future efforts for drought resistance improvement in common bean.
基金the National Science and Technology Support Program of China(2015BAA05B02).
文摘Coal is the dominant energy source in China,and coal-fired power accounts for about half of coal consumption.However,air pollutant emissions from coal-fired power plants cause severe ecological and environmental problems.This paper focuses on near-zero emission technologies and applications for clean coal-fired power.The long-term operation states of near-zero emission units were evaluated,and synergistic and special mercury(Hg)control technologies were researched.The results show that the principle technical route of near-zero emission,which was applied to 101 of China’s coal-fired units,has good adaptability to coal properties.The emission concentrations of particulate matter(PM),SO2,and NOx were below the emission limits of gas-fired power plants and the compliance rates of the hourly average emission concentrations reaching near-zero emission in long-term operation exceeded 99%.With the application of near-zero emission technologies,the generating costs increased by about 0.01 CNY∙(kW∙h)-1.However,the total emissions of air pollutants decreased by about 90%,resulting in effective improvement of the ambient air quality.Furthermore,while the Hg emission concentrations of the near-zero emission units ranged from 0.51 to 2.89μg∙m^-3,after the modified fly ash(MFA)special Hg removal system was applied,Hg emission concentration reached as low as 0.29μg∙m^-3.The operating cost of this system was only 10%-15%of the cost of mainstream Hg removal technology using activated carbon injection.Based on experimental studies carried out in a 50000 m^3∙h^-1 coal-fired flue gas pollutant control pilot platform,the interaction relationships of multi-pollutant removal were obtained and solutions were developed for emissions reaching different limits.A combined demonstration application for clean coal-fired power,with the new“1123”eco-friendly emission limits of 1,10,20 mg∙m^-3,and 3μg∙m^-3,respectively,for PM,SO2,NOx,and Hg from near-zero emission coal-fired power were put forward and realized,providing engineering and technical support for the national enhanced pollution emission standards.
基金supported by an earmarked fund for China Agriculture Research System (No. CARS-09)the Agricultural Science and Technology Innovation Program (ASTIP) of CAASthe Higher Education Institution Key Research Project Plan of Henan Province (No. 15A210042)
文摘As a typical compatible solute, proline is accumulated in plants under environmental stresses. Proline transporter(Pro T) plays an important role in proline distribution between plant organs. Using a candidate gene approach, we cloned a c DNA sequence for Pro T from common bean(Phaseolus vulgaris L.) and designated the gene Pv Pro T. The deduced amino acid sequence of Pv Pro T showed high similarity to Bet/Pro T proteins from other leguminous plants, and the highest similarity was observed with mothbean(Vigna aconitifolia L.) Vu Pro T.Relative quantification of the m RNA level of Pv Pro T using real-time PCR analysis showed that the Pv Pro T transcript level was higher in leaves than in stems and roots of common bean plants subjected to drought and salt stress. Under 20%(w/w) PEG-6000 treatment,drought-resistant plants expressed a higher level of Pv Pro T transcripts than droughtsensitive plants. Although heterologous expression of Pv Pro T in the Escherichia coli mutant mkh13 showed that Pv Pro T exhibited uptake activities for proline and betaine, no betaine content was detected in the common bean. These findings suggest that Pv Pro T plays an important role in the transportation of proline in common bean plants exposed to drought and salt stress.
基金supported by the National Natural Science Foundation of China(Nos.61474073,61874069 and 61804157).
文摘The ultrahigh vacuum scanning tunneling microscope(STM)was used to characterize the GaSb_(1-x)Bi_(x) films of a few nanometers thickness grown by the molecular beam epitaxy(MBE)on the GaSb buffer layer of 100 nm with the GaSb(100)substrates.The thickness of the GaSb_(1-x)Bi_(x) layers of the samples are 5 and 10 nm,respectively.For comparison,the GaSb buffer was also characterized and its STM image displays terraces whose surfaces are basically atomically flat and their roughness is generally less than 1 monolayer(ML).The surface of 5 nm GaSb_(1-x)Bi_(x) film reserves the same terraced morphology as the buffer layer.In contrast,the morphology of the 10 nm GaSb_(1-x)Bi_(x) film changes to the mound-like island structures with a height of a few MLs.The result implies the growth mode transition from the two-dimensional mode as displayed by the 5 nm film to the Stranski-Krastinov mode as displayed by the 10 nm film.The statistical analysis with the scanning tunneling spectroscopy(STS)measurements indicates that both the incorporation and the inhomogeneity of Bi atoms increase with the thickness of the GaSb_(1-x)Bi_(x) layer.
文摘This special issue is focused on grain legumes,which belong to the Fabaceae family.Legumes are the second largest family of plants in the world after the grasses and are key components of manmade and natural ecosystems[1–3].They provide the environmental service of nitrogen fixation,so essential to soil construction and fertility maintenance,and are thus essential to agricultural systems[4,5].Different species of legumes range from huge trees to shrubs
基金supported by the National Natural Science Foundation of China (31471559)the China Agriculture Research System (CARS-09)+2 种基金the National Key Technology R&D Program of China (2013BAD01B03-18a)the Evans Allen Fund of the U.S. Department of Agriculturethe Agricultural Science and Technology Innovation Program (ASTIP) of the Chinese Academy of Agricultural Sciences
文摘Common bacterial blight(CBB), caused by Xanthomonas axonopodis pv. phaseoli and Xanthomonas fuscans subsp. fuscans(Xff), is a worldwide disease of common bean(Phaseolus vulgaris L.).Longyundou 5, a Chinese cultivar in the Mesoamerican gene pool of common bean, displays resistance to the Xff strain XSC3-1. To identify the genetic mechanisms behind this resistance,we crossed Long 5 with a susceptible genotype to develop a mapping population of F2 plants.Plant resistance to CBB was identified at 14 and 21 days after inoculation with Xff strain XSC3-1.A major QTL at 14 and 21 days after inoculation was mapped on chromosome Pv10 with LOD scores of 6.41 and 5.35, respectively. This locus was associated with SAP6, a previouslyidentified and much-used dominant marker, but in a 4.2 cM interval between new codominant markers BMp10s174 and BMp10s244. Ten candidate genes were found between markers BMp10s174 and BMp10s244 on chromosome Pv10 and could encode defense response proteins responding to CBB pathogens. Four pairs each of epistatic QTL for CBB resistance were detected at 14 and 21 days after inoculation. Phenotypic variation explained by the epistatic QTL ranged from 7.19% to 12.15% and 7.72% to 8.80% at 14 and 21 days after inoculation, respectively. These results confirmed the importance of epistasis in CBB resistance in common bean. The adjacent markers found may be more efficient for marker assisted selection in common bean breeding for CBB resistance owing to their closer linkage to the target QTL.
文摘InAs/GaSb type-II superlattce (T2SL) photodetector structures at the MWIR regime were grown by molecular beam epitaxy. The growth temperature and group-V soaking times were optimized with respect to interface and transport quality. Novel strain compensation schemes with insertion of InSb layers were proposed and tested to be efficient to tune the overall strain between tensile and compressive without degradation of interface and optical quality. The effect of the proposed methods is modeled by analytic functions.? Band structure calculations were also carried out for the proposed T2SL structures to assist optimizing sample designs. Single pixel photodiodes with a low dark current were demonstrated.
基金Supported by the National Basic Research Program of China under Grant No 2014CB643902the Key Program of Natural Science Foundation of China under Grant No 61334004+3 种基金the National Natural Science Foundation of China under Grant No 61404152the Strategic Priority Research Program of the Chinese Academy of Sciences under Grant No XDA5-1the Foundation of National Laboratory for Infrared Physics,the Key Research Program of the Chinese Academy of Sciences under Grant No KGZDEW-804the Creative Research Group Project of Natural Science Foundation of China under Grant No 61321492
文摘Optical gains of type-Ⅱ In Ga As/Ga As Bi quantum wells(QWs) with W, N, and M shapes are analyzed theoretically for near-infrared laser applications. The bandgap and wave functions are calculated using the self-consistent k·p Hamiltonian, taking into account valence band mixing and the strain effect. Our calculations show that the M-shaped type-Ⅱ QWs are a promising structure for making 1.3 um lasers at room temperature because they can easily be used to obtain 1.3 um for photoluminescence with a proper thickness and have large wave-function overlap for high optical gain.
基金Project supported by the National Key Research and Development Program of China(Grant No.2017YFE0131300)the National Natural Science Foundation of China(Grant Nos.U1732268,61874128,11622545,61851406,11705262,and 61804157)+5 种基金the Frontier Science Key Program of the Chinese Academy of Sciences(Grant No.QYZDY-SSW-JSC032)the Chinese-Austrian Cooperative Research and Development Project(Grant No.GJHZ201950)the Science and Technology Innovation Action Plan Program of Shanghai,China(Grant No.17511106202)the Program of Shanghai Academic Research Leader,China(Grant No.19XD1404600)the Sailing Program of Shanghai,China(Grant Nos.19YF1456200 and 19YF1456400)the K C Wong Education Foundation(Grant No.GJTD-2019-11).
文摘Strain and stress were simulated using finite element method(FEM)for threeⅢ-V-on-Insulator(Ⅲ-VOI)structures,i.e.,InP/SiO2/Si,InP/Al2O3/SiO2/Si,and GaAs/Al2O3/SiO2/Si,fabricated by ion-slicing as the substrates for optoelectronic devices on Si.The thermal strain/stress imposes no risk for optoelectronic structures grown on InPOI at a normal growth temperature using molecular beam epitaxy.Structures grown on GaAsOI are more dangerous than those on InPOI due to a limited critical thickness.The intermedia Al2O3 layer was intended to increase the adherence while it brings in the largest risk.The simulated results reveal thermal stress on Al2O3 over 1 GPa,which is much higher than its critical stress for interfacial fracture.InPOI without an Al2O3 layer is more suitable as the substrate for optoelectronic integration on Si.
文摘The characteristics of highway transport and the application of information technology in highway transport service are combined; the information flows' promotion and substitution on highway transport are analyzed; and the highway transport development strategy based on information flow impact is proposed.
基金supported by the National Key R&D Program of China(2019YFA0210004,2022YFA1502904,2021YFA1501502)the National Natural Science Foundation of China(22125503,21975242,U2032212,21890754,22002148)+1 种基金2023 Synchrotron Radiation Joint Fund of USTCthe Youth Innovation Promotion Association of CAS(CX2340007003)。
文摘Photocatalytic CH_(4) coupling into high-valued C_(2)H_(6) is highly attractive,whereas the photosynthetic rate,especially under oxygen-free system,is still unsatisfying.Here,we designed the negatively charged metal supported on metal oxide nanosheets to activate the inert C-H bond in CH_(4)and hence accelerate CH_(4) coupling performance.As an example,the synthetic Au/ZnO porous nanosheets exhibit the C_(2)H_(6) photosynthetic rate of 1,121.6μmol g^(-1)_(cat)h^(-1)and the CH_(4) conversion rate of 2,374.6μmol g^(-1)_(cat)h^(-1) under oxygen-free system,2 orders of magnitude higher than those of previously reported photocatalysts.By virtue of several in situ spectroscopic techniques,it is established that the generated Au^(δ-)and O^-species together polarized the C-H bond,while the Au^(δ-)and O^-species jointly stabilized the CH_(3) intermediates,which favored the coupling of CH_(3) intermediate to photosynthesize C_(2)H_(6) instead of overoxidation into CO_(x).Thus,the design of dual active species is beneficial for achieving high-efficient CH_(4)-to-C_(2)H_(6) photoconversion.
基金supported by the National Key Research and Development Project(No.2019YFC0214800)the Science and Technology Innovation Project of China Energy Investment Corporation Limited(No.51609225)Tsinghua-Foshan Innovation Special Fund(No.2020THFS0102)。
文摘China has established the largest clean coal-fired power generation system in the world by accomplishing the technological transformation of coal-fired power plants(CFPPs)to achieve ultra-low emission.The potential for further particulate matter(PM)emission reduction to achieve near-zero emission for CFPPs has become a hotspot issue.In this study,PM emission from some ultra-low emission CFPPs adopting advanced air pollutant control technologies in China was reviewed.The results revealed that the average filterable particulate matter(FPM)concentration,measured as the total particulate matter(TPM)according to the current national monitoring standard,was(1.67±0.86)mg/m^(3),which could fully achieve the ultra-low emission standard for key regions(5 mg/m^(3)),but that achieving the near-zero emission standard was difficult(1 mg/m^(3)).However,the condensable particulate matter(CPM),with an average concentration of(1.06±1.28)mg/m^(3),was generally ignored during monitoring,which led to about 38.7%underestimation of the TPM.Even considering both FPM and CPM,the TPM emission from current CFPPs would contribute to less than 5%of atmospheric PM_(2.5) concentrations in the key cities and regions in China.Therefore,further reduction in FPM emission proposed by the near-zero emission plan of CFPPs may have less environmental benefit than emission control of other anthropogenic sources.However,it is suggested that the management of CPM emission should be strengthened,and a national standard for CPM emission monitoring based on the indirect dilution method should be established for CFPPs.Those measurements are helpful for optimal operation of air pollutant control devices and continuously promoting further emission reduction.
基金supported by the China Postdoctoral Science Foundation(No.2022M712157)China National Postdoctoral Program for Innovative Talents(No.BX20220215)+5 种基金China Scientific Research Foundation of Peking University Shenzhen Hospital(No.KYQD202100X)the National Natural Science Foundation of China(No.32101074)Shenzhen Science and Technology Innovation Committee Discipline Layout Project(No.JCYJ20170816105345191)National University of Singapore Start-up Grant(No.NUHSRO/2020/133/Startup/08)NUS School of Medicine Nanomedicine Translational Research Programme(No.NUHSRO/2021/034/TRP/09/Nanomedicine)the National Medical Research Council(NMRC)Centre Grant Programme(No.CG21APR1005).
文摘The development of efficient contrast agents for tumor-targeted imaging remains a critical challenge in the clinic.Herein,we proposed a tumor-derived extracellular vesicle(EV)-mediated targeting approach to improve in vivo tumor imaging using ternary downconversion nanoparticles(DCNPs)with strong near infrared II(NIR-II)luminescence at 1,525 nm.The EVs were metabolically engineered with azide group,followed by in vivo labeling of DCNPs through copper-free click chemistry.By taking advantage of the homologous targeting property of tumor derived EVs,remarkable improvement in the tumor accumulation(6.5%injection dose(ID)/g)was achieved in the subcutaneous colorectal cancer model when compared to that of individual DCNPs via passive targeting(1.1%ID/g).Importantly,such bioorthogonal labeling significantly increased NIR-II luminescence signals and prolonged the retention at tumor sites.Our work demonstrates the great potential of EVs-mediated bioorthogonal approach for in vivo labeling of NIR-II optical probes,which provides a robust tool for tumor-specific imaging and targeted therapy.
基金supported by the National Natural Science Foundation of China(Nos.21874024,32101074,and U21A20377)the Joint Research Program of Health and Education Commission of Fujian Province(No.2019-WJ-20)the Natural Science Foundation of Fujian Province(No.2020J02012).
文摘Photocatalytic antibacterial approach shows great potential in treating multidrug-resistant bacterial infections.However,the bactericidal efficiency heavily depends on the photocatalytic activity of semiconductor materials,which is limited by the fast recombination of photogenerated electron–hole pairs.Janus nano-heterostructures with spatial control growth of TiO_(2)nanoparticles(NPs)at one end of gold nanorods(Au NRs)are designed via surface ligand regulation for photocatalytic sterilization and infected wound healing.The asymmetric nanostructure of Janus gold nanorod-titanium dioxide nanoparticles(Janus AuNR-TiO_(2) NPs)promotes the directional migration of charge carriers and is more conducive to the spatial separation of electron–hole pairs.Moreover,the injection of hot electrons and enhancement of plasmon near-fields from the surface plasmon resonance(SPR)effect further improve the photocatalytic efficiency of Janus AuNR-TiO_(2) NPs.Under simulated sunlight irradiation,large amounts of reactive oxygen species(ROS)are generated for photocatalytic antibacterial activity.Enhanced bactericidal efficiency up to 99.99%against methicillin-resistant Staphylococcus aureus(MRSA)is achieved in vitro.Furthermore,Janus AuNR-TiO_(2) NPs exhibit superior biocompatibility,structural stability,and also remarkably accelerate MRSA-infected wound healing.Taking the above all into consideration,Janus AuNR-TiO_(2) NPs,as an efficient antibacterial photocatalyst,offers a promising strategy for MRSA infectious therapy.
基金The procedures of insect capture and measurement are under the Wildlife Conservation Law of China(20170101).
文摘Predator–prey interaction has long been an interesting item in the research of animal behaviors.Given that live prey can damage their predators,predators must trade foraging efficiency for safety while hunting,but the extent of this trade-off is not yet clear.Tiger beetles display diversity in their diets and hunting strategies,and hence,they become an ideal system to address how self-security affects foraging efficiency.We addressed this question in captive adult tiger beetles Cicindela gemmata.By offering several types of arthropod and plant foods,we confirmed that C.gemmata is carnivorous.We found that C.gemmata hunt by either ambushing or chasing their prey,and that they switch between strategies based on differences in the number of prey,the prey status and encounter rate,and the number of predators.Ambushing success increased with the number of prey but decreased with prey encounter rate.Chasing success decreased as prey body size and encounter rate increased.Foraging Cicindela gemmata often gave up an attack when it was nonfatal.This active giving up of hunting may be a consequence of a trade-off between foraging efficiency and self-security.Therefore,it is an adaptive response to the risk of injury when hunting for larger live prey.
基金China National Major Project for New Drug Innovation,Grant/Award Number:2017ZX09304015Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(CIFMS),Grant/Award Number:2016-I2M-1-001。
文摘Background:Previous studies have demonstrated the preclinical pharmacological and toxicological consistency,and clinical pharmacokinetic equivalence of bevacizumab biosimilar LY01008 with reference bevacizumab(Avastin).This randomized controlled trial aimed to compare the efficacy and safety of LY01008 with Avastin in first-line treatment of Chinese patients with advanced or recurrent non-squamous non-small cell lung cancer(NSCLC).Methods:StageⅢB-ⅣNSCLC patients with evaluable lesions,good physical status,and adequate organ functions from 67 centers across China were randomized in a ratio of 1:1 to receive LY01008 or Avastin 15 mg/kg intravenously in combination with paclitaxel/carboplatin(combined treatment)for 4-6 cycles,followed by maintenance monotherapy with LY01008 until disease progression,intolerable toxicity,or death.The primary endpoint was objective response rate(ORR)in accordance with Response Evaluation Criteria in Solid Tumors(RECIST)version 1.1 confirmed by independent radiological review committees(IRRC).Secondary endpoints included disease control rate(DCR),duration of response(DoR),progression-free survival(PFS),overall survival(OS),and safety.This study was registered in Clinical Trials.gov(NCT03533127).Results:Between December 15^(th),2017,and May 15^(th),2019,a total of 649 patients were randomized to the LY01008(n=324)or Avastin(n=325)group.As of September 25th,2019 for primary endpoint analysis,589 patients received ORR evaluation,with a median number of combined treatment cycles of 5(range 1-6)andmedian duration of treatment of 3.0(range 0.0-5.1)months.ORRof responseevaluable patients in the LY01008 and Avastin groups were 48.5% and 53.0%,respectively.The stratified ORR ratio was 0.91(90%CI 0.80-1.04,within the prespecified equivalence margin of 0.75-1.33).Up to May 15^(th),2020,with a median follow-up of 13.6(range 0.8-28.4)months,no notable differences in DCR,median DoR,median PFS,median OS,and 1-year OS rate were observed between the LY01008 and Avastin groups.There were no clinically meaningful differences in safety and immunogenicity across treatment groups.Conclusions:LY01008 demonstrated similarity to Avastin in terms of efficacy and safety in Chinese patients with advanced or recurrent non-squamous NSCLC.LY01008 combined with paclitaxel/carboplatin is expected to become a new treatment option for unresectable,metastatic,LY01008 and Avastin groups.There were no clinically meaningful differences in safety and immunogenicity across treatment groups.Conclusions:LY01008 demonstrated similarity to Avastin in terms of efficacy and safety in Chinese patients with advanced or recurrent non-squamous NSCLC.LY01008 combined with paclitaxel/carboplatin is expected to become a new treatment option for unresectable,metastatic,or recurrent non-squamous NSCLC patients in the first-line setting.