High-temperature polymer electrolyte membrane fuel cells (HT-PEMFCs) show excellent application prospects due to its enhanced tolerance of hydrogen impurity.However,the sluggish electrode kinetics caused by its ineffi...High-temperature polymer electrolyte membrane fuel cells (HT-PEMFCs) show excellent application prospects due to its enhanced tolerance of hydrogen impurity.However,the sluggish electrode kinetics caused by its inefficient electrocatalytic interface and proton transfer severely restricts its performance.To overcome the sluggish electrode kinetics,the ethylenediamine tetramethylenephosphonic acid(EDTMPA) was successfully incorporated into the catalysts layer to regulate the phosphoric acid (PA) distribution to boost the electrocatalytic reaction interface and proton transfer,thus increasing the output power and stability of HT-PEMFCs.The hydrophilic H_(2)PO_(4)^(-) and electron donor N atom of EDTMPA could efficiently decrease the absorption of PA on the catalyst surface and facilitate proton transportation in the membrane electrode,as demonstrated by our experiments.The fuel cell assembled with the prepared membrane electrode shows a high reactivity of 1175 mW cm^(-2)and excellent stability,which is much better than the past reference report.The results of this work provide new insights into the utilization of small molecules with phosphate groups to enhance phosphate tolerance and proton conduction,and there is also a further improvement in the reactivity,durability,and utilization of the electrocatalysts in HT-PEMFCs.展开更多
Super-resolution imaging with superlens has been one of the fundamental research topics. Unfortunately, the resolution of superlens is inevitably restrained by material loss. To address the problem, we introduce the s...Super-resolution imaging with superlens has been one of the fundamental research topics. Unfortunately, the resolution of superlens is inevitably restrained by material loss. To address the problem, we introduce the solid immersion mechanism into the slab superlens and the cylindrical superlens. The proposed solid immersion slab superlens(SISSL) and the solid immersion cylindrical superlens(SICSL) can improve the resolution by converting evanescent wave to propagating wave using high refractive index materials. From the perspective of applications, the cylindrical superlens with finite cross section and the ability of magnification or demagnification has more advantages than the slab superlens. Therefore,we focus on demonstrating analytically the super-resolution imaging of SICSL. Due to the impedance mismatching caused by solid immersion mechanism, the whispering gallery modes(WGMs) are excited between SICSL and the air interface.We clarify the excitation conditions of WGMs and analyze their influence on the imaging quality of SICSL. The SISSL and SICSL may pave a way to apply in lithography technique and real-time biomolecular imaging in future.展开更多
Recently,in cooperation with the Netherlands Cancer Institute,we demonstrated that epidermal growth factor receptor(EGFR)activation limited the response of liver cancer to lenvatinib.The original article was published...Recently,in cooperation with the Netherlands Cancer Institute,we demonstrated that epidermal growth factor receptor(EGFR)activation limited the response of liver cancer to lenvatinib.The original article was published in Nature as a cover story,which resulted in considerable attention from major scientific journals.Here,we were invited by Cancer Biology&Medicine to provide comments on preclinical and clinical findings about the combination of lenvatinib plus EGFR inhibitors as a promising strategy for hepatocellular carcinoma(HCC)treatment.Primary liver cancer represents the sixth most common malignancy and the third leading cause of cancer-related mortality worldwide,with an estimated 906,000 new cases and 830,000 deaths in 20201.展开更多
1.Introduction As an important resource,forests not only provide irreplaceable economic benefits,but also yield ecological benefits that maintain the balance of terrestrial ecosystems.In addition,forests are an energy...1.Introduction As an important resource,forests not only provide irreplaceable economic benefits,but also yield ecological benefits that maintain the balance of terrestrial ecosystems.In addition,forests are an energy base of the biosphere.With the development of information-based technologies and globalization,accurate information regarding individual trees and standing forests in forest resource investigations is increasingly needed in order to achieve sustainable development of forestry[1–6].As an important means of obtaining information,unmanned aerial vehicles(UAVs)are becoming increasingly popular in a wide range of fields,given their developmental trends of miniaturization and diversification[7–9].Moreover,geographic information system(GIS)technology,as another type of core technology in the digital world,is undergoing rapid development.展开更多
Super-resolution imaging is vital for optical applications, such as high capacity information transmission, real-time bio-molecular imaging, and nanolithography. In recent years, technologies and methods of super-reso...Super-resolution imaging is vital for optical applications, such as high capacity information transmission, real-time bio-molecular imaging, and nanolithography. In recent years, technologies and methods of super-resolution imaging have attracted much attention. Different kinds of novel lenses, from the superlens to the super-oscillatory lens, have been designed and fabricated to break through the diffraction limit. However, the effect of the super-resolution imaging in these lenses is not satisfactory due to intrinsic loss, aberration, large sidebands, and so on. Moreover, these lenses also cannot realize multiple super-resolution imaging. In this research, we introduce the solid immersion mechanism to Mikaelian lens(ML) for multiple super-resolution imaging. The effect is robust and valid for broadband frequencies. Based on conformal transformation optics as a bridge linking the solid immersion ML and generalized Maxwell's fish-eye lens(GMFEL), we also discovered the effect of multiple super-resolution imaging in the solid immersion GMFEL.展开更多
Surface modification techniques with plasma are widely investigated to improve the surface insulation capability of polymers under dry conditions,while the relationship between treatment method,surface physical and ch...Surface modification techniques with plasma are widely investigated to improve the surface insulation capability of polymers under dry conditions,while the relationship between treatment method,surface physical and chemical properties,and wet flashover voltage is still unclear for inorganic ceramics.In this work,the surface insulation properties of ceramics under wet conditions are improved using nanosecond-pulsed dielectric barrier discharge with polydimethylsiloxane(PDMS)as the precursor.The relationships between PDMS concentration and the water contact angle,dry and wet flashover voltages are obtained to acquire the optimal concentration.The surface charge dissipation test and surface physio-chemical property measurement with SEM,AFM,XPS are carried out to further explore the mechanism of surface insulation enhancement.The results show that film deposition with micron thickness and superhydrophobicity occurs at the PDMS concentration of 1.5%.The dry flashover voltage is increased by 14.6%due to the induction of deep traps,while the wet flashover voltage is increased by 66.7%.The gap between dry-wet flashover voltage is decreased by 62.3%compared with the untreated one due to the self-cleaning effect.展开更多
Immature embryos of inbred maize(Zea mays)lines(H8183,H8184,and H8185)were used for Agrobacterium infection.We used theβ-glucuronidase gene(GUS)as the target gene and the glufosinate resistance gene(bar)as the select...Immature embryos of inbred maize(Zea mays)lines(H8183,H8184,and H8185)were used for Agrobacterium infection.We used theβ-glucuronidase gene(GUS)as the target gene and the glufosinate resistance gene(bar)as the selection marker.We conducted research on several aspects,such as different genotypes,coculture conditions,screening agent concentrations,and concentrations of indole-3-butytric acid(IBA),6-benzylaminopurine(6-BA),and ascorbic acid(Vc)in the differentiation medium.We optimized the genetic transformation system,and the obtained results indicated that among the three lines studied,the induction rate of H8185 was the highest at 93.2%,followed by H8184,with H8183 having the lowest induction rate(80.1%).The best coculture method was that using the N6 coculture medium layered with a sterile filter paper.Using orthogonal analysis,we found that the optimal combination of the three factors in the differentiation medium was A_(3)(1 mg mL^(−1)IBA),B_(3)C_(1)(1.6 mg mL^(−1)6-BA),and D_(3)(1.5 mg mL^(−1)Vc).Through GUS staining analysis,Bar test-strip analysis,and polymerase chain reaction,five transgenic plants were finally obtained.This study established the optimal conditions for genetic transformation in maize.展开更多
Maize flowering is an important agronomic character,which is controlled by quantitative trait loci(QTL).Over the years,a large number of flowering-related QTL have been found in maize and exist in public databases.How...Maize flowering is an important agronomic character,which is controlled by quantitative trait loci(QTL).Over the years,a large number of flowering-related QTL have been found in maize and exist in public databases.However,combining these data,re-analyzing and mining candidate loci and fine mapping of flowering-related traits to reduce confidence intervals has become a hot issue in maize.In this study,the QTL of 6 important agronomic traits of maize flowering were collected from 15 published articles,including flowering period(DA),Days to tasseling(DTT),Days to silking(DS),Days to pollen shedding(DTP),anthesis-silking interval(ASI)and the photosensitive(PS).Through meta-analysis,622 QTL were integrated into 26 meta-QTLs(MQTL).Finally,the candidate genes related to maize flowering(Gene IDs:ZM00001D005791,ZM00001D019045,ZM00001D050697,ZM00001D011139)were identified by Gene Ontology(GO)enrichment and hierarchical cluster analysis of expression profile.Based on the results of this study,the genetic characteristics of maize flowering traits will be further analyzed,which is of great significance to guide the improvement of important agronomic characters and improve the efficiency of breeding.展开更多
The energy crisis has aroused widespread concern, and the reform of energy structure is imminent. In the future,the energy structure will be dominated by the solar energy and other renewable energy sources. The solar ...The energy crisis has aroused widespread concern, and the reform of energy structure is imminent. In the future,the energy structure will be dominated by the solar energy and other renewable energy sources. The solar concentrating technology as a promising method has been widely studied for collecting solar energy. However, the previous solar concentrating technologies suffer from some drawbacks, such as low focusing efficiency and large concentrating size. The Luneburg lens with highly efficient aberration-free focusing provides a new route for solar/energy concentrator. In this work, we designed a plane focal surface Luneburg lens(PFSLL) by transformation optics(TO). The PFSLL provides a relatively high focusing efficiency and concentration ratio of collection of energy. At the same time, it circumvents the disadvantage of curve surface of the classical Luneburg lens in device integration. Based on the reciprocity of electromagnetic waves, the PFSLL can also be applied to the antenna field to achieve broadband wide-angle scanning and highly directional radiation.展开更多
In electrochemical energy devices,the operating conditions always exert enormous influence on electrocatalysts'performances.Phosphoric acid(PA),acted as the proton carriers,can be adsorbed on Pt surface,block acti...In electrochemical energy devices,the operating conditions always exert enormous influence on electrocatalysts'performances.Phosphoric acid(PA),acted as the proton carriers,can be adsorbed on Pt surface,block active sites and affect the electronic structure of Pt unfavorably,which severely restricts the performance of high-temperature proton exchange membrane fuel cells(HT-PEMFCs).Herein,simply basic organic compounds,such as dicyandiamide(DCD),melamine(Mel)and cyanuric acid(CA),are decorated on Pt surface(DCD-Pt/C,Mel-Pt/C and CA-Pt/C)to induce the adsorption transfer of proton carriers.The decoration can not only inject electrons to Pt and enhance oxygen reduction reaction(ORR)activity but also can induce PA to transfer from Pt surface to organic compounds,decontaminating active sites.In addition,the organic compounds with the larger conjugated system and the smaller electronegativity of ligating atoms would have a greater interaction with Pt,causing a larger decoration amount on Pt surface,which leads to more excellent ORR activity and resistance to PA blockage effect.Therefore,MelPt/C shows a peak power density of 629 mW/cm^(2),exceeding commercial Pt/C(437 mW/cm^(2)),DCD-Pt/C(539 m W/cm^(2))and CA-Pt/C(511 mW/cm^(2))with the same loading.展开更多
With the development of synthesis technology, modified messenger RNA(mRNA) has emerged as a novel category of therapeutic agents for a broad of diseases. However, effective intracellular delivery of mRNA remains chall...With the development of synthesis technology, modified messenger RNA(mRNA) has emerged as a novel category of therapeutic agents for a broad of diseases. However, effective intracellular delivery of mRNA remains challenging, especially for its sensitivity to enzymatic degradation. Here, we propose a polyphenol-assisted handy delivery strategy for efficient in vivo delivery of IL-10 mRNA.IL-10 mRNA binds to polyphenol ellagic acid through supramolecular binding to yield a negatively charged core, followed by complexing with linear polyetherimide and coating with bilirubin-modified hyaluronic acid to obtain a layer-by-layer nanostructure. The nanostructure specifically up-regulated the level of IL-10, effectively inhibited the expression of inflammatory factors, promoted mucosal repair, protected colonic epithelial cells against apoptosis, and exerted potent therapeutic efficacy in dextran sulfate sodium salt-induced acute and chronic murine models of colitis. The designed delivery system without systemic toxicity has the potential to facilitate the development of a promising platform for mRNA delivery in ulcerative colitis treatment.展开更多
Patients with COVID-19 have revealed a massive outbreak around the world,leading to widespread concerns in global scope.Figuring out the transmission route of COVID-19 is necessary to control further spread.We analyze...Patients with COVID-19 have revealed a massive outbreak around the world,leading to widespread concerns in global scope.Figuring out the transmission route of COVID-19 is necessary to control further spread.We analyzed the data of 43 patients in Baodi Department Store(China)to supplement the transmission route and epidemiological characteristics of COVID-19 in a cluster outbreak.Incubation median was estimated to endure 5.95 days(2-13 days).Almost 76.3%of patients sought medical attention immediately upon illness onset.The median period of illness onset to hospitalization and confirmation were 3.96 days(0-14)and 5.58 days(1-21),respectively.Patients with different cluster case could demonstrate unique epidemiological characteristics due to the particularity of outbreak sites.SRAS-CoV-2 can be released into the surrounding air through patient's respiratory tract activities,and can exist for a long time for long-distance transportation.SRAS-CoV-2 RNA can be detected in aerosol in different sites,including isolation ward,general ward,outdoor,toilet,hallway,and crowded public area.Environmental factors influencing were analyzed and indicated that the SARS-CoV-2 transportation in aerosol was dependent on temperature,air humidity,ventilation rate and inactivating chemicals(ozone)content.As for the infection route of case numbers 2 to 6,10,13,16,17,18,20 and 23,we believe that aerosol transmission played a significant role in analyzing their exposure history and environmental conditions in Baodi Department Store.Aerosol transmission could occur in some cluster cases when the environmental factors are suitable,and it is an indispensable route of COVID-19 spread.展开更多
In the current world,people have ever-increasing demand for energy.Fossil fuels are now the primary source of energy,and their excess use results in severe problems,such as environmental pollution and global warming.C...In the current world,people have ever-increasing demand for energy.Fossil fuels are now the primary source of energy,and their excess use results in severe problems,such as environmental pollution and global warming.Consequently,it is essential to develop a new society based on sustainable energies such as wind,tidal and solar energy sources.Due to the intermittence and instability of the above new energies,smart grids with the core technology展开更多
Herein,we report a microwave-assisted acid-induced post-treatment method for the formation of linker vacancies within Zr-based metal organic frameworks(Zr-MOFs).The number of linker vacancies can be easily regulated w...Herein,we report a microwave-assisted acid-induced post-treatment method for the formation of linker vacancies within Zr-based metal organic frameworks(Zr-MOFs).The number of linker vacancies can be easily regulated with this method by changing the concentration of the HCl solution and the duration of microwave irradiation.The optimized defective UiO-66 showed higher linker defects with a higher specific surface area and thermal stability.The results of the catalytic cyclization of citronella showed that the Zr-MOFs with more defects exhibited enhanced catalytic performance.This work may provide a new method for the creation of defective MOFs with high activity and stability.展开更多
PICKLE(PKL), a putative CHD3 chromatin remodeling factor, has been suggested to be involved in multiple processes in Arabidopsis. Here, we confirmed the late-flowering phenotype caused by pkl mutation with pkl mutants...PICKLE(PKL), a putative CHD3 chromatin remodeling factor, has been suggested to be involved in multiple processes in Arabidopsis. Here, we confirmed the late-flowering phenotype caused by pkl mutation with pkl mutants in two different ecotypes, and investigated the possible mechanisms that account for PKL regulation of flowering time. Quantitative RT-PCR and RNA-seq assays showed that expression of the LEAFY gene(LFY) and a number of LFY-regulated floral homeotic genes were down-regulated in seedlings of the pkl mutants. As predicted, overexpression of LFY restored normal flowering time of pkl mutants. Our results suggest that PKL may be involved in regulating flowering time via LFY expression. To uncover the underlying mechanism, Ch IP-PCR using anti-PKL was performed on materials from three developmental stages of seedlings. Our results showed that PKL associated with the genomic sequences of LFY, particularly at 10-day and 25-day after germination. We also showed that loss of PKL affected H3K27me3 level at the promoter of LFY. Taken together, our data suggest that transcriptional regulation of LFY at the chromatin level by PKL may at least partially account for the late-flowering phenotype of pkl mutants.展开更多
Background:This study analyzed the safety and efficacy of Enterprise 2 stent-assisted coil embolization for wide-necked intracranial aneurysms by examining stent-vessel apposition,operative complications,embolization ...Background:This study analyzed the safety and efficacy of Enterprise 2 stent-assisted coil embolization for wide-necked intracranial aneurysms by examining stent-vessel apposition,operative complications,embolization outcomes,and clinical outcomes.Methods:We retrospectively reviewed the medical records of patients with wide-necked intracranial aneurysms who underwent Enterprise 2 stent-assisted coiling in our hospital from November 2018 to October 2019.Intraoperative VasoCT was performed immediately after stent release in a continuous cohort of patients to observe stent-vessel apposition.Patient demographic,clinical,and imaging data were recorded and analyzed.Results:A total of 106 wide-necked aneurysms in 106 patients were treated.Stent release was successful in all patients.Twenty-one patients were enrolled consecutively for VasoCT scanning,and incomplete stent apposition was observed in 5(23.8%).Perioperative complications occurred in 10 patients(9.4%):cerebral infarction in 6,intraoperative coil prolapse in 1,puncture site pseudoaneurysm in 1,deep vein thrombosis at multiple sites in 1,and transient brainstem mass effect in 1.Among the 95 aneurysms with angiographic follow-up,embolization was satisfactory(Raymond-Roy classifications I and II)in 89(93.7%).Hyperlipidemia was an independent risk factor for incomplete aneurysm occlusion.At the last clinical follow-up,seven patients had a poor clinical outcome(modified Rankin Scale score≥3).Independent risk factors for poor outcomes were preoperative subarachnoid hemorrhage at presentation and cerebral infarction.Conclusion:Enterprise 2 stent-assisted coiling for treatment of wide-necked intracranial aneurysms showed good safety and efficacy;however,incomplete stent apposition can still occur in vessels with a large curvature.Preoperative subarachnoid hemorrhage at presentation and cerebral infarction are the main reasons for poor clinical outcomes after stent-assisted coil embolization.展开更多
Broadband super-resolution imaging is important in the optical field.To achieve super-resolution imaging,various lenses from a superlens to a solid immersion lens have been designed and fabricated in recent years.Howe...Broadband super-resolution imaging is important in the optical field.To achieve super-resolution imaging,various lenses from a superlens to a solid immersion lens have been designed and fabricated in recent years.However,the imaging is unsatisfactory due to low work efficiency and narrow band.In this work,we propose a solid immersion square Maxwell's fish-eye lens,which realizes broadband(7-16 GHz)achromatic super-resolution imaging with full width at half-maximum around 0.2λ based on transformation optics at microwave frequencies.In addition,a super-resolution information transmission channel is also designed to realize long-distance multi-source super-resolution information transmission based on the super-resolution lens.With the development of 3D printing technology,the solid immersion Maxwell's fish-eye lens is expected to be fabricated in the high-frequency band.展开更多
Whispering-gallery-mode(WGM)cavity is important for exploring physics of strong light-matter interaction.Yet it suffers from the notorious radiation loss universally due to the light tunneling effect through the curve...Whispering-gallery-mode(WGM)cavity is important for exploring physics of strong light-matter interaction.Yet it suffers from the notorious radiation loss universally due to the light tunneling effect through the curved boundary.In this work,we propose and demonstrate an optical black hole(OBH)cavity based on transformation optics.The radiation loss of all WGMs in the ideal OBH cavity is completely inhibited by an infinite wide potential barrier.Besides,the WGM field in the OBH cladding is revealed to follow 1/rdecay rule based on conformal mapping,which is fundamentally different from the conventional Hankel-function distributions in a homogeneous cavity.Experimentally,a truncated OBH cavity is achieved based on the effective medium theory,and both the Q-factor enhancement and tightly confined WGM fields are measured in the microwave spectra which agree well with the theoretical results.The circular OBH cavity is further applied to the arbitrary-shaped cavities including single-core and multi-core structures with high-Q factor via the conformal mapping.The OBH cavity design strategy can be generalized to resonant modes of various wave systems,such as acoustic and elastic waves,and finds applications in energy harvesting and optoelectronics.展开更多
Background and purpose Light transmission aggregometry(LTA)and CYP2C19 genotype analysis are commonly used to evaluate the antiplatelet effects of clopidogrel during the interventional treatment of intracranial aneury...Background and purpose Light transmission aggregometry(LTA)and CYP2C19 genotype analysis are commonly used to evaluate the antiplatelet effects of clopidogrel during the interventional treatment of intracranial aneurysms.The aim of this study was to determine which test can predict ischaemic events during these treatments.Methods Patient demographic information,imaging data,laboratory data and ischaemic complications were recorded.LTA and CYP2C19 genotype results were compared,and multiple linear regression was performed to examine factors related to platelet reactivity.Multivariate regression analysis was performed to determine whether LTA and CYP2C19 could predict ischaemic complications and to identify other clinical risk factors.Receiver operating characteristic curve analysis was conducted to calculate the cut-off value for predicting ischaemic complications.A subgroup analysis was also performed for different CYP2C19 genotype metabolisers,as well as for patients with flow diverters and traditional stents.Results A total of 379 patients were included,of which 22 developed ischaemic events.Maximum platelet aggregation induced by ADP(ADP-MPA)could predict ischaemic events(p<0.001;area under the curve,0.752(95%CI 0.663 to 0.842)),and its cut-off value was 41.5%.ADP-MPA(p=0.001)and hypertension duration>10 years(p=0.022)were independent risk factors for ischaemic events,while the CYP2C19 genotype was not associated with ischaemic events.In the subgroup analysis,ADP-MPA could predict ischaemic events in fast metabolisers(p=0.004)and intermediate metabolisers(p=0.003).The cut-off value for ischaemic events was lower in patients with flow diverters(ADP-MPA=36.4%)than in patients with traditional stents(ADP-MPA=42.9%).Conclusions ADP-MPA can predict ischaemic complications during endovascular treatment of intracranial aneurysms.Patients with flow diverters require stronger antiplatelet medication than patients with traditional stents.展开更多
The dialogue system has always been one of the important topics in the domain of artificial intelligence.So far,most of the mature dialogue systems are task-oriented based,while non-task-oriented dialogue systems stil...The dialogue system has always been one of the important topics in the domain of artificial intelligence.So far,most of the mature dialogue systems are task-oriented based,while non-task-oriented dialogue systems still have a lot of room for improvement.We propose a data-driven non-task-oriented dialogue generator“CERG”based on neural networks.This model has the emotion recognition capability and can generate corresponding responses.The data set we adopt comes from the NTCIR-14 STC-3 CECG subtask,which contains more than 1.7 million Chinese Weibo post-response pairs and 6 emotion categories.We try to concatenate the post and the response with the emotion,then mask the response part of the input text character by character to emulate the encoder-decoder framework.We use the improved transformer blocks as the core to build the model and add regularization methods to alleviate the problems of overcorrection and exposure bias.We introduce the retrieval method to the inference process to improve the semantic relevance of generated responses.The results of the manual evaluation show that our proposed model can make different responses to different emotions to improve the human-computer interaction experience.This model can be applied to lots of domains,such as automatic reply robots of social application.展开更多
基金financially supported by the National Key R&D Program of China (2021YFA 1500900)the National Natural Science Foundation of China (Grant No.:22425021, 22102053)+5 种基金the Provincial Natural Science Foundation of Hunan (2024JJ2012)the Science and Technology Innovation Program of Hunan Province (Grant Nos.2022RC1036)the Top ten Technological Breakthrough Projects in Hunan Province (2023GK1050)the Guangdong Basic and Applied Basic Research Foundation (2024A1515012889)the Shenzhen Science and technology program (JCYJ20210324122209025)the Major Program of the Natural Science Foundation of Hunan Province(2021JC0006)。
文摘High-temperature polymer electrolyte membrane fuel cells (HT-PEMFCs) show excellent application prospects due to its enhanced tolerance of hydrogen impurity.However,the sluggish electrode kinetics caused by its inefficient electrocatalytic interface and proton transfer severely restricts its performance.To overcome the sluggish electrode kinetics,the ethylenediamine tetramethylenephosphonic acid(EDTMPA) was successfully incorporated into the catalysts layer to regulate the phosphoric acid (PA) distribution to boost the electrocatalytic reaction interface and proton transfer,thus increasing the output power and stability of HT-PEMFCs.The hydrophilic H_(2)PO_(4)^(-) and electron donor N atom of EDTMPA could efficiently decrease the absorption of PA on the catalyst surface and facilitate proton transportation in the membrane electrode,as demonstrated by our experiments.The fuel cell assembled with the prepared membrane electrode shows a high reactivity of 1175 mW cm^(-2)and excellent stability,which is much better than the past reference report.The results of this work provide new insights into the utilization of small molecules with phosphate groups to enhance phosphate tolerance and proton conduction,and there is also a further improvement in the reactivity,durability,and utilization of the electrocatalysts in HT-PEMFCs.
基金Project supported by the National Key Research and Development Program of China (Grant No. 2020YFA0710100)the National Natural Science Foundation of China (Grant Nos. 92050102 and 11874311)the Fundamental Research Funds for the Central Universities (Grant Nos. 20720220033 and 20720200074)。
文摘Super-resolution imaging with superlens has been one of the fundamental research topics. Unfortunately, the resolution of superlens is inevitably restrained by material loss. To address the problem, we introduce the solid immersion mechanism into the slab superlens and the cylindrical superlens. The proposed solid immersion slab superlens(SISSL) and the solid immersion cylindrical superlens(SICSL) can improve the resolution by converting evanescent wave to propagating wave using high refractive index materials. From the perspective of applications, the cylindrical superlens with finite cross section and the ability of magnification or demagnification has more advantages than the slab superlens. Therefore,we focus on demonstrating analytically the super-resolution imaging of SICSL. Due to the impedance mismatching caused by solid immersion mechanism, the whispering gallery modes(WGMs) are excited between SICSL and the air interface.We clarify the excitation conditions of WGMs and analyze their influence on the imaging quality of SICSL. The SISSL and SICSL may pave a way to apply in lithography technique and real-time biomolecular imaging in future.
基金This work was supported by grants from the National Natural Science Foundation of China(Grant No.81920108025)the Shanghai Municipal Science and Technology Project(Grant No.20JC1411100)the 111 Project(Grant No.B21024).
文摘Recently,in cooperation with the Netherlands Cancer Institute,we demonstrated that epidermal growth factor receptor(EGFR)activation limited the response of liver cancer to lenvatinib.The original article was published in Nature as a cover story,which resulted in considerable attention from major scientific journals.Here,we were invited by Cancer Biology&Medicine to provide comments on preclinical and clinical findings about the combination of lenvatinib plus EGFR inhibitors as a promising strategy for hepatocellular carcinoma(HCC)treatment.Primary liver cancer represents the sixth most common malignancy and the third leading cause of cancer-related mortality worldwide,with an estimated 906,000 new cases and 830,000 deaths in 20201.
基金We are grateful to the staff of the Precision Forestry Key Laboratory of Beijing,Beijing Forestry University,and to acknowledge all the people who have contributed to this paperThis research was jointly supported by the Fundamental Research Funds for the Central Universities(2015ZCQ-LX-01)the National Natural Science Foundation of China(U1710123).
文摘1.Introduction As an important resource,forests not only provide irreplaceable economic benefits,but also yield ecological benefits that maintain the balance of terrestrial ecosystems.In addition,forests are an energy base of the biosphere.With the development of information-based technologies and globalization,accurate information regarding individual trees and standing forests in forest resource investigations is increasingly needed in order to achieve sustainable development of forestry[1–6].As an important means of obtaining information,unmanned aerial vehicles(UAVs)are becoming increasingly popular in a wide range of fields,given their developmental trends of miniaturization and diversification[7–9].Moreover,geographic information system(GIS)technology,as another type of core technology in the digital world,is undergoing rapid development.
基金Project supported by the National Natural Science Foundation of China (Grant No. 92050102)the National Key Research and Development Program of China (Grant No. 2020YFA0710100)the Fundamental Research Funds for Central Universities, China (Grant Nos. 20720200074, 20720220134, 202006310051, and 20720220033)。
文摘Super-resolution imaging is vital for optical applications, such as high capacity information transmission, real-time bio-molecular imaging, and nanolithography. In recent years, technologies and methods of super-resolution imaging have attracted much attention. Different kinds of novel lenses, from the superlens to the super-oscillatory lens, have been designed and fabricated to break through the diffraction limit. However, the effect of the super-resolution imaging in these lenses is not satisfactory due to intrinsic loss, aberration, large sidebands, and so on. Moreover, these lenses also cannot realize multiple super-resolution imaging. In this research, we introduce the solid immersion mechanism to Mikaelian lens(ML) for multiple super-resolution imaging. The effect is robust and valid for broadband frequencies. Based on conformal transformation optics as a bridge linking the solid immersion ML and generalized Maxwell's fish-eye lens(GMFEL), we also discovered the effect of multiple super-resolution imaging in the solid immersion GMFEL.
基金partially supported by National Natural Science Foundation of China(Nos.51977104,52037004 and 52207160)the Natural Science Foundation of Jiangsu Province(No.BK20220341)。
文摘Surface modification techniques with plasma are widely investigated to improve the surface insulation capability of polymers under dry conditions,while the relationship between treatment method,surface physical and chemical properties,and wet flashover voltage is still unclear for inorganic ceramics.In this work,the surface insulation properties of ceramics under wet conditions are improved using nanosecond-pulsed dielectric barrier discharge with polydimethylsiloxane(PDMS)as the precursor.The relationships between PDMS concentration and the water contact angle,dry and wet flashover voltages are obtained to acquire the optimal concentration.The surface charge dissipation test and surface physio-chemical property measurement with SEM,AFM,XPS are carried out to further explore the mechanism of surface insulation enhancement.The results show that film deposition with micron thickness and superhydrophobicity occurs at the PDMS concentration of 1.5%.The dry flashover voltage is increased by 14.6%due to the induction of deep traps,while the wet flashover voltage is increased by 66.7%.The gap between dry-wet flashover voltage is decreased by 62.3%compared with the untreated one due to the self-cleaning effect.
基金This work was supported by Jilin Provincial Natural Science Foundation Project[20190201168JC]“Thirteenth Five-Year”Science and Technology Project of Jilin Provincial Department of Education[JJKH20200341KJ]+3 种基金Science and Technology Project of Jilin Provincial Department of Education[JJKH20210351KJ,JJKH20210346KJ]Jilin Province Science and Technology Development Plan Project[20200402023NC]Jilin Province Key Technology R&D Project[20180201029NY]Jilin Province Support for the Science and Technology Development Program[20190802012ZG]College Student Innovation and Entrepreneurship Training Program Project[202010193087].Furthermore,the funding body have no role in designing of study,collection and interpretation of data or writing up the manuscript.
文摘Immature embryos of inbred maize(Zea mays)lines(H8183,H8184,and H8185)were used for Agrobacterium infection.We used theβ-glucuronidase gene(GUS)as the target gene and the glufosinate resistance gene(bar)as the selection marker.We conducted research on several aspects,such as different genotypes,coculture conditions,screening agent concentrations,and concentrations of indole-3-butytric acid(IBA),6-benzylaminopurine(6-BA),and ascorbic acid(Vc)in the differentiation medium.We optimized the genetic transformation system,and the obtained results indicated that among the three lines studied,the induction rate of H8185 was the highest at 93.2%,followed by H8184,with H8183 having the lowest induction rate(80.1%).The best coculture method was that using the N6 coculture medium layered with a sterile filter paper.Using orthogonal analysis,we found that the optimal combination of the three factors in the differentiation medium was A_(3)(1 mg mL^(−1)IBA),B_(3)C_(1)(1.6 mg mL^(−1)6-BA),and D_(3)(1.5 mg mL^(−1)Vc).Through GUS staining analysis,Bar test-strip analysis,and polymerase chain reaction,five transgenic plants were finally obtained.This study established the optimal conditions for genetic transformation in maize.
基金Science and Technology Project of Jilin Provincial Department of Education[JJKH20210351KJ,JJKH20210346KJ]Jilin Province Science and Technology Development Plan Project[20200402023NC]。
文摘Maize flowering is an important agronomic character,which is controlled by quantitative trait loci(QTL).Over the years,a large number of flowering-related QTL have been found in maize and exist in public databases.However,combining these data,re-analyzing and mining candidate loci and fine mapping of flowering-related traits to reduce confidence intervals has become a hot issue in maize.In this study,the QTL of 6 important agronomic traits of maize flowering were collected from 15 published articles,including flowering period(DA),Days to tasseling(DTT),Days to silking(DS),Days to pollen shedding(DTP),anthesis-silking interval(ASI)and the photosensitive(PS).Through meta-analysis,622 QTL were integrated into 26 meta-QTLs(MQTL).Finally,the candidate genes related to maize flowering(Gene IDs:ZM00001D005791,ZM00001D019045,ZM00001D050697,ZM00001D011139)were identified by Gene Ontology(GO)enrichment and hierarchical cluster analysis of expression profile.Based on the results of this study,the genetic characteristics of maize flowering traits will be further analyzed,which is of great significance to guide the improvement of important agronomic characters and improve the efficiency of breeding.
基金Project supported by the National Key Research and Development Program of China (Grant No. 2020YFA0710100)the National Natural Science Foundation of China (Grant Nos. 92050102 and 11874311)+1 种基金the Shenzhen Science and Technology Program (Grant No. JCYJ20210324121610028)the Fundamental Research Funds for the Central Universities (Grant Nos. 20720220033 and 20720200074)。
文摘The energy crisis has aroused widespread concern, and the reform of energy structure is imminent. In the future,the energy structure will be dominated by the solar energy and other renewable energy sources. The solar concentrating technology as a promising method has been widely studied for collecting solar energy. However, the previous solar concentrating technologies suffer from some drawbacks, such as low focusing efficiency and large concentrating size. The Luneburg lens with highly efficient aberration-free focusing provides a new route for solar/energy concentrator. In this work, we designed a plane focal surface Luneburg lens(PFSLL) by transformation optics(TO). The PFSLL provides a relatively high focusing efficiency and concentration ratio of collection of energy. At the same time, it circumvents the disadvantage of curve surface of the classical Luneburg lens in device integration. Based on the reciprocity of electromagnetic waves, the PFSLL can also be applied to the antenna field to achieve broadband wide-angle scanning and highly directional radiation.
基金supported by the National Key R&D Program of China(No.2021YFA1500900)the National Natural Science Foundation of China(Nos.22102053,21825201,22172047 and U19A2017)+7 种基金the Provincial Natural Science Foundation of Hunan(Nos.2019GK2031,2016TP1009,2020JJ5045 and 2021JJ30089)the Science and Technology Innovation Program of Hunan Province,China(Nos.2020RC2020,2022RC1036)Shenzhen Science and Technology Program(No.JCYJ20210324122209025)Basic and Applied Basic Research Foundation of Guangdong Province-Regional joint fund project(No.2021B1515120024)Natural Science Foundation of Chongqing(No.cstc2021jcyj-msxmX0770)the Science Funds of the Education Office of Jiangxi Province(No.GJJ2201324)the Science Funds of Jiangxi Province(No.20224BAB213018)the China Postdoctoral Science Foundation(Certificate No.2023M741121)。
文摘In electrochemical energy devices,the operating conditions always exert enormous influence on electrocatalysts'performances.Phosphoric acid(PA),acted as the proton carriers,can be adsorbed on Pt surface,block active sites and affect the electronic structure of Pt unfavorably,which severely restricts the performance of high-temperature proton exchange membrane fuel cells(HT-PEMFCs).Herein,simply basic organic compounds,such as dicyandiamide(DCD),melamine(Mel)and cyanuric acid(CA),are decorated on Pt surface(DCD-Pt/C,Mel-Pt/C and CA-Pt/C)to induce the adsorption transfer of proton carriers.The decoration can not only inject electrons to Pt and enhance oxygen reduction reaction(ORR)activity but also can induce PA to transfer from Pt surface to organic compounds,decontaminating active sites.In addition,the organic compounds with the larger conjugated system and the smaller electronegativity of ligating atoms would have a greater interaction with Pt,causing a larger decoration amount on Pt surface,which leads to more excellent ORR activity and resistance to PA blockage effect.Therefore,MelPt/C shows a peak power density of 629 mW/cm^(2),exceeding commercial Pt/C(437 mW/cm^(2)),DCD-Pt/C(539 m W/cm^(2))and CA-Pt/C(511 mW/cm^(2))with the same loading.
基金funded by the Science and Technology Development Fund,Macao SAR (00151/2020/A3 & SKL-QRCM(UM)2020-2022,China)Major Basic and Applied Basic Research Projects of Guangdong Province of China (2019B030302005)+1 种基金Guangxi Science and Technology Research Project (GuiKe AA18242040,China)the University of Macao (MYRG2020-00141-ICMS and EF013/ICMS-WYT/2019/GPU,China)。
文摘With the development of synthesis technology, modified messenger RNA(mRNA) has emerged as a novel category of therapeutic agents for a broad of diseases. However, effective intracellular delivery of mRNA remains challenging, especially for its sensitivity to enzymatic degradation. Here, we propose a polyphenol-assisted handy delivery strategy for efficient in vivo delivery of IL-10 mRNA.IL-10 mRNA binds to polyphenol ellagic acid through supramolecular binding to yield a negatively charged core, followed by complexing with linear polyetherimide and coating with bilirubin-modified hyaluronic acid to obtain a layer-by-layer nanostructure. The nanostructure specifically up-regulated the level of IL-10, effectively inhibited the expression of inflammatory factors, promoted mucosal repair, protected colonic epithelial cells against apoptosis, and exerted potent therapeutic efficacy in dextran sulfate sodium salt-induced acute and chronic murine models of colitis. The designed delivery system without systemic toxicity has the potential to facilitate the development of a promising platform for mRNA delivery in ulcerative colitis treatment.
基金the Key Technologies R&D Program of Tianjin(No.20ZXGBSY00100)。
文摘Patients with COVID-19 have revealed a massive outbreak around the world,leading to widespread concerns in global scope.Figuring out the transmission route of COVID-19 is necessary to control further spread.We analyzed the data of 43 patients in Baodi Department Store(China)to supplement the transmission route and epidemiological characteristics of COVID-19 in a cluster outbreak.Incubation median was estimated to endure 5.95 days(2-13 days).Almost 76.3%of patients sought medical attention immediately upon illness onset.The median period of illness onset to hospitalization and confirmation were 3.96 days(0-14)and 5.58 days(1-21),respectively.Patients with different cluster case could demonstrate unique epidemiological characteristics due to the particularity of outbreak sites.SRAS-CoV-2 can be released into the surrounding air through patient's respiratory tract activities,and can exist for a long time for long-distance transportation.SRAS-CoV-2 RNA can be detected in aerosol in different sites,including isolation ward,general ward,outdoor,toilet,hallway,and crowded public area.Environmental factors influencing were analyzed and indicated that the SARS-CoV-2 transportation in aerosol was dependent on temperature,air humidity,ventilation rate and inactivating chemicals(ozone)content.As for the infection route of case numbers 2 to 6,10,13,16,17,18,20 and 23,we believe that aerosol transmission played a significant role in analyzing their exposure history and environmental conditions in Baodi Department Store.Aerosol transmission could occur in some cluster cases when the environmental factors are suitable,and it is an indispensable route of COVID-19 spread.
基金supported by the National Natural Science Foundation of China(21773126)the ‘‘100 Projects" of Creative Research for the Undergraduates of Nankai University(BX15250)
文摘In the current world,people have ever-increasing demand for energy.Fossil fuels are now the primary source of energy,and their excess use results in severe problems,such as environmental pollution and global warming.Consequently,it is essential to develop a new society based on sustainable energies such as wind,tidal and solar energy sources.Due to the intermittence and instability of the above new energies,smart grids with the core technology
基金supported by the National Natural Science Foundation of China (No.21573063)the Hunan Provincial Natural Science Foundation of Youth Fund (No.2020JJ3002)+1 种基金Open Fund from Hunan Provincial Key Laboratory of Advanced Materials for New Energy Storage and Conversion (No.2018TP1037201902)the Training Program of Hunan University of Youth Fund。
文摘Herein,we report a microwave-assisted acid-induced post-treatment method for the formation of linker vacancies within Zr-based metal organic frameworks(Zr-MOFs).The number of linker vacancies can be easily regulated with this method by changing the concentration of the HCl solution and the duration of microwave irradiation.The optimized defective UiO-66 showed higher linker defects with a higher specific surface area and thermal stability.The results of the catalytic cyclization of citronella showed that the Zr-MOFs with more defects exhibited enhanced catalytic performance.This work may provide a new method for the creation of defective MOFs with high activity and stability.
文摘PICKLE(PKL), a putative CHD3 chromatin remodeling factor, has been suggested to be involved in multiple processes in Arabidopsis. Here, we confirmed the late-flowering phenotype caused by pkl mutation with pkl mutants in two different ecotypes, and investigated the possible mechanisms that account for PKL regulation of flowering time. Quantitative RT-PCR and RNA-seq assays showed that expression of the LEAFY gene(LFY) and a number of LFY-regulated floral homeotic genes were down-regulated in seedlings of the pkl mutants. As predicted, overexpression of LFY restored normal flowering time of pkl mutants. Our results suggest that PKL may be involved in regulating flowering time via LFY expression. To uncover the underlying mechanism, Ch IP-PCR using anti-PKL was performed on materials from three developmental stages of seedlings. Our results showed that PKL associated with the genomic sequences of LFY, particularly at 10-day and 25-day after germination. We also showed that loss of PKL affected H3K27me3 level at the promoter of LFY. Taken together, our data suggest that transcriptional regulation of LFY at the chromatin level by PKL may at least partially account for the late-flowering phenotype of pkl mutants.
文摘Background:This study analyzed the safety and efficacy of Enterprise 2 stent-assisted coil embolization for wide-necked intracranial aneurysms by examining stent-vessel apposition,operative complications,embolization outcomes,and clinical outcomes.Methods:We retrospectively reviewed the medical records of patients with wide-necked intracranial aneurysms who underwent Enterprise 2 stent-assisted coiling in our hospital from November 2018 to October 2019.Intraoperative VasoCT was performed immediately after stent release in a continuous cohort of patients to observe stent-vessel apposition.Patient demographic,clinical,and imaging data were recorded and analyzed.Results:A total of 106 wide-necked aneurysms in 106 patients were treated.Stent release was successful in all patients.Twenty-one patients were enrolled consecutively for VasoCT scanning,and incomplete stent apposition was observed in 5(23.8%).Perioperative complications occurred in 10 patients(9.4%):cerebral infarction in 6,intraoperative coil prolapse in 1,puncture site pseudoaneurysm in 1,deep vein thrombosis at multiple sites in 1,and transient brainstem mass effect in 1.Among the 95 aneurysms with angiographic follow-up,embolization was satisfactory(Raymond-Roy classifications I and II)in 89(93.7%).Hyperlipidemia was an independent risk factor for incomplete aneurysm occlusion.At the last clinical follow-up,seven patients had a poor clinical outcome(modified Rankin Scale score≥3).Independent risk factors for poor outcomes were preoperative subarachnoid hemorrhage at presentation and cerebral infarction.Conclusion:Enterprise 2 stent-assisted coiling for treatment of wide-necked intracranial aneurysms showed good safety and efficacy;however,incomplete stent apposition can still occur in vessels with a large curvature.Preoperative subarachnoid hemorrhage at presentation and cerebral infarction are the main reasons for poor clinical outcomes after stent-assisted coil embolization.
基金This work was supported by the National Key Research and Development Program of China(No.2020YFA0710100)National Natural Science Foundation of China(Nos.92050102 and 11874311)Fundamental Research Funds for the Central Universities(No.20720200074).
文摘Broadband super-resolution imaging is important in the optical field.To achieve super-resolution imaging,various lenses from a superlens to a solid immersion lens have been designed and fabricated in recent years.However,the imaging is unsatisfactory due to low work efficiency and narrow band.In this work,we propose a solid immersion square Maxwell's fish-eye lens,which realizes broadband(7-16 GHz)achromatic super-resolution imaging with full width at half-maximum around 0.2λ based on transformation optics at microwave frequencies.In addition,a super-resolution information transmission channel is also designed to realize long-distance multi-source super-resolution information transmission based on the super-resolution lens.With the development of 3D printing technology,the solid immersion Maxwell's fish-eye lens is expected to be fabricated in the high-frequency band.
基金National Key Research and Development Program of China(2020YFA0710100)National Natural Science Foundation of China(62005231,92050102)Fundamental Research Funds for the Central Universities(20720210045,20720200074,20720220033,and 20720220134)。
文摘Whispering-gallery-mode(WGM)cavity is important for exploring physics of strong light-matter interaction.Yet it suffers from the notorious radiation loss universally due to the light tunneling effect through the curved boundary.In this work,we propose and demonstrate an optical black hole(OBH)cavity based on transformation optics.The radiation loss of all WGMs in the ideal OBH cavity is completely inhibited by an infinite wide potential barrier.Besides,the WGM field in the OBH cladding is revealed to follow 1/rdecay rule based on conformal mapping,which is fundamentally different from the conventional Hankel-function distributions in a homogeneous cavity.Experimentally,a truncated OBH cavity is achieved based on the effective medium theory,and both the Q-factor enhancement and tightly confined WGM fields are measured in the microwave spectra which agree well with the theoretical results.The circular OBH cavity is further applied to the arbitrary-shaped cavities including single-core and multi-core structures with high-Q factor via the conformal mapping.The OBH cavity design strategy can be generalized to resonant modes of various wave systems,such as acoustic and elastic waves,and finds applications in energy harvesting and optoelectronics.
基金funded by the National Natural Science Foundation of China(81671139 and 82072036)Capital's Funds for Health Improvement and Research(2022-1-2041)and Summit Talent Program(DFL20220503).
文摘Background and purpose Light transmission aggregometry(LTA)and CYP2C19 genotype analysis are commonly used to evaluate the antiplatelet effects of clopidogrel during the interventional treatment of intracranial aneurysms.The aim of this study was to determine which test can predict ischaemic events during these treatments.Methods Patient demographic information,imaging data,laboratory data and ischaemic complications were recorded.LTA and CYP2C19 genotype results were compared,and multiple linear regression was performed to examine factors related to platelet reactivity.Multivariate regression analysis was performed to determine whether LTA and CYP2C19 could predict ischaemic complications and to identify other clinical risk factors.Receiver operating characteristic curve analysis was conducted to calculate the cut-off value for predicting ischaemic complications.A subgroup analysis was also performed for different CYP2C19 genotype metabolisers,as well as for patients with flow diverters and traditional stents.Results A total of 379 patients were included,of which 22 developed ischaemic events.Maximum platelet aggregation induced by ADP(ADP-MPA)could predict ischaemic events(p<0.001;area under the curve,0.752(95%CI 0.663 to 0.842)),and its cut-off value was 41.5%.ADP-MPA(p=0.001)and hypertension duration>10 years(p=0.022)were independent risk factors for ischaemic events,while the CYP2C19 genotype was not associated with ischaemic events.In the subgroup analysis,ADP-MPA could predict ischaemic events in fast metabolisers(p=0.004)and intermediate metabolisers(p=0.003).The cut-off value for ischaemic events was lower in patients with flow diverters(ADP-MPA=36.4%)than in patients with traditional stents(ADP-MPA=42.9%).Conclusions ADP-MPA can predict ischaemic complications during endovascular treatment of intracranial aneurysms.Patients with flow diverters require stronger antiplatelet medication than patients with traditional stents.
基金This work was partially supported by the Research Clusters Program of Tokushima University.
文摘The dialogue system has always been one of the important topics in the domain of artificial intelligence.So far,most of the mature dialogue systems are task-oriented based,while non-task-oriented dialogue systems still have a lot of room for improvement.We propose a data-driven non-task-oriented dialogue generator“CERG”based on neural networks.This model has the emotion recognition capability and can generate corresponding responses.The data set we adopt comes from the NTCIR-14 STC-3 CECG subtask,which contains more than 1.7 million Chinese Weibo post-response pairs and 6 emotion categories.We try to concatenate the post and the response with the emotion,then mask the response part of the input text character by character to emulate the encoder-decoder framework.We use the improved transformer blocks as the core to build the model and add regularization methods to alleviate the problems of overcorrection and exposure bias.We introduce the retrieval method to the inference process to improve the semantic relevance of generated responses.The results of the manual evaluation show that our proposed model can make different responses to different emotions to improve the human-computer interaction experience.This model can be applied to lots of domains,such as automatic reply robots of social application.
