The rapid development and widespread use of ZnO nanoparticles(nZnO) in various industries have raised concerns about their potential environmental impact.Therefore,understanding the fate and role of nZnO in the natura...The rapid development and widespread use of ZnO nanoparticles(nZnO) in various industries have raised concerns about their potential environmental impact.Therefore,understanding the fate and role of nZnO in the natural environment is crucial for mitigating their hazardous effects on the environment and human safety.The purpose of the present study was to provide scientific support for understanding and eliminating the joint risk of nanoparticle and heavy metal pollution in the soil environment by revealing the co-transport characteristics of Cd(Ⅱ) and ZnO nanoparticles(nZnO) in soil under different ionic strength(IS) and pH.The impacts of different IS and pH on the co-transport of Cd(Ⅱ) and nZnO in a20 cm long with an inner diameter of 2.5 cm acrylic column packed with 10 cm high soil samples were investigated in the present study.In the above system,a500 μg L^(-1) Cd(Ⅱ) loaded nZnO suspension pulse with varying IS or pH was introduced into the soil column for leaching over 5 PVs,followed up by 5 PVs background solutions without nZnO.The IS was 1,10,or 50 mM NaCl,with pH6,or the pH was 6,7 or 8 with 1 mM NaCl.Meanwhile,Sedimentation experiments for nZnO,adsorption of Cd(Ⅱ) on soil,and nZnO,DLVO theory calculation for the same background condition were conducted.The presence of nZnO significantly increased the mobility of Cd(Ⅱ) as a result of its strong adsorption capacity for nZnO-associated Cd(Ⅱ).However,with the increase of IS,the co-transport of nZnO and Cd(Ⅱ) was decreased and the retention of nZnO in the soil column due to more nZnO attended to aggregate and sediment during the transport and the decrease in the adsorption capacity of nZnO for Cd(Ⅱ) by competition of Na^(+).When pH was 6,7,and 8,the co-transport of nZnO and Cd(Ⅱ) increased with higher pH due to the lower electrostatic attraction between nZnO and soil under higher pH.Meanwhile,the DLVO theory was fitted to describe the above co-transport process of nZnO and Cd(Ⅱ).More attention should be paid to the presence of nZnO on the migration of Cd(Ⅱ) in the natural soil to control the potential risk of nanoparticles and heavy metals to the environment.The risk of co-transport of nZnO and Cd(Ⅱ) might be controlled by adjusting IS and pH in the soil solution.展开更多
This study aimed to characterize and identify calcium-chelating peptides from rabbit bone collagen and explore the underlying chelating mechanism.Collagen peptides and calcium were extracted from rabbit bone by instan...This study aimed to characterize and identify calcium-chelating peptides from rabbit bone collagen and explore the underlying chelating mechanism.Collagen peptides and calcium were extracted from rabbit bone by instant ejection steam explosion(ICSE)combined with enzymatic hydrolysis,followed by chelation reaction to prepare rabbit bone peptide-calcium chelate(RBCP-Ca).The chelating sites were further analyzed by liquid chromatography-tandem mass(LC-MS/MS)spectrometry while the chelating mechanism and binding modes were investigated.The structural characterization revealed that RBCP successfully chelated with calcium ions.Furthermore,LC-MS/MS analysis indicated that the binding sites included both acidic amino acids(Asp and Glu)and basic amino acids(Lys and Arg),Interestingly,three binding modes,namely Inter-Linking,Loop-Linking and Mono-Linking were for the first time found,while Inter-Linking mode accounted for the highest proportion(75.1%),suggesting that chelation of calcium ions frequently occurred between two peptides.Overall,this study provides a theoretical basis for the elucidation of chelation mechanism of calcium-chelating peptides.展开更多
Photocatalysis is an environmentally friendly and energy-saving technology, which can effectively remove persistent dangerous pollutants in the water. Pitifully, optical absorption capacity and carrier separation have...Photocatalysis is an environmentally friendly and energy-saving technology, which can effectively remove persistent dangerous pollutants in the water. Pitifully, optical absorption capacity and carrier separation have become major bottlenecks for marvelous photocatalytic performance of photocatalysts.Herein, to address these issue, Nanodiamonds/yolk-shell ZnFe_(2)O_(4) spheres(NDs/ZFO) nanocomposites were successfully constructed via a facile two-step of solvothermal and calcination methods. The synthesized optimal NDs/ZFO-10 nanocomposite exhibits superior photocatalytic degradation activity of antibiotic under visible light, approximately 85% of the total tetracycline(TC) is degraded, and this photocatalyst shows durable cycling stability. This stems from two aspects of refinement: improvement of light absorption capacity and photo-induced charges migration and separation. In addition, the NDs/ZFO composite photocatalyst features excellent magnetic recovery capability, facilitating the recovery of photocatalyst in industry. This study opens a new chapter in the combination of NDs with magnetic materials, and deepens the understanding of the application of NDs modified composite photocatalysts.展开更多
There is currently great optimism within the electronics community that gallium oxide(Ga_(2)O_(3)) ultra-wide bandgap semiconductors have unprecedented prospects for eventually revolutionizing a rich variety of power ...There is currently great optimism within the electronics community that gallium oxide(Ga_(2)O_(3)) ultra-wide bandgap semiconductors have unprecedented prospects for eventually revolutionizing a rich variety of power electronic applications. Specially, benefiting from its ultra-high bandgap of around 4.8 eV, it is expected that the emerging Ga_(2)O_(3) technology would offer an exciting platform to deliver massively enhanced device performance for power electronics and even completely new applications.展开更多
Gallium oxide(Ga_(2)O_(3))has garnered world-wide atten-tion as an ultrawide-bandgap semiconductor material from the area of power electronics and DUV optical devices benefit-ing from its outstanding electronic and op...Gallium oxide(Ga_(2)O_(3))has garnered world-wide atten-tion as an ultrawide-bandgap semiconductor material from the area of power electronics and DUV optical devices benefit-ing from its outstanding electronic and optoelectronic proper-ties.For one thing,since Ga_(2)O_(3)features high critical break-down field of 8 MV/cm and Baliga’s figure of merit(BFOM)of 3444,it is a promising candidate for advanced high-power applications.For another thing,due to the bandgap directly corresponding to the deep-ultraviolet(DUV)region,Ga_(2)O_(3)is widely used in DUV optoelectronic devices.展开更多
Objective:Cold exposure has been suggested to be advantageous for the spread and infection of the coronavirus,and the gut microbiota influences the severity of the infection by modulating host inflammatory and immune ...Objective:Cold exposure has been suggested to be advantageous for the spread and infection of the coronavirus,and the gut microbiota influences the severity of the infection by modulating host inflammatory and immune responses.However,it remains unclear whether the promotion of viral infection through cold exposure is linked to the gut microbiota.Methods:In this study,we performed an unbiased analysis of gut microbiota,serum,and lung tissue metabolome changes in cold-exposed and virus-infected mice,alongside the assessment of immune-inflammatory indicators in serum and lung tissue.Results:The results revealed that both cold exposure and viral infection significantly decreased the percentage of peripheral blood lymphocytes(CD4^(+)T cells,CD8^(+)T cells,and B cell)and increased the expression of inflammatory factors(IL-6,IL-1β,TNF-α,and IFN-γ).Meanwhile,cold exposure disrupted the homeostasis of gut microbiota,elevating the abundance of pathogenic bacteria(Staphylococcus)and diminishing the abundance of beneficial bacteria(Alistipes).Notably,in virus-infected mice exposed to a cold environment,the reduction in the abundance of beneficial bacteria Alistipes was more pronounced than in cases of single virus infection and cold exposure.Analysis of altered serum and lung tissue metabolites highlighted glycerophospholipids,fatty acids,and eicosanoids as the most affected metabolites by cold exposure.These metabolites,closely associated with virus infection,exhibited a significant correlation with immune-inflammatory indicators.Conclusion:These findings establish a mechanistic connection between cold exposure and virus infection,suggesting that cold exposure-induced dysregulation of gut microbiota and lipid metabolism diminishes host immunity,promoting virus infection.展开更多
Ultraviolet(UV)-induced photoaging skin has become an urgent issue.The functional foods and cosmetics aiming to improve skin photoaging are developing rapidly,and the demand is gradually increasing year by year.Collag...Ultraviolet(UV)-induced photoaging skin has become an urgent issue.The functional foods and cosmetics aiming to improve skin photoaging are developing rapidly,and the demand is gradually increasing year by year.Collagen peptides have been proven to display diverse physiological activities,such as excellent moisture retention activity,hygroscopicity,tyrosinase inhibitory activity and antioxidant activity,which indicates that they have great potential in amelioration of UV-induced photoaging.The main objective of this article is to recap the main mechanisms to improve photoaging skin by collagen peptides and their physiological activities in photo-protection.Furthermore,the extraction and structural characteristics of collagen peptides are overviewed.More importantly,some clinical trials on the beneficial effect on skin of collagen peptides are also discussed.In addition,prospects and challenges of collagen peptides are emphatically elucidated in this review.This article implies that collagen peptides have great potential as an effective ingredient in food and cosmetics industry with a wide application prospect.展开更多
The joint extraction of entities and their relations from certain texts plays a significant role in most natural language processes.For entity and relation extraction in a specific domain,we propose a hybrid neural fr...The joint extraction of entities and their relations from certain texts plays a significant role in most natural language processes.For entity and relation extraction in a specific domain,we propose a hybrid neural framework consisting of two parts:a span-based model and a graph-based model.The span-based model can tackle overlapping problems compared with BILOU methods,whereas the graph-based model treats relation prediction as graph classification.Our main contribution is to incorporate external lexical and syntactic knowledge of a specific domain,such as domain dictionaries and dependency structures from texts,into end-to-end neural models.We conducted extensive experiments on a Chinese military entity and relation extraction corpus.The results show that the proposed framework outperforms the baselines with better performance in terms of entity and relation prediction.The proposed method provides insight into problems with the joint extraction of entities and their relations.展开更多
The control of crystal growth is important but challenging for multi-disciplinary research.Violet phosphorus,the most stable phosphorus allotrope,has recently been produced as a unique semiconducting layered structure...The control of crystal growth is important but challenging for multi-disciplinary research.Violet phosphorus,the most stable phosphorus allotrope,has recently been produced as a unique semiconducting layered structure.The crystal orientation and morphology bring extra performance due to its unique structure and anisotropy.Herein,the layered violet phosphorus has been controlled to grow along the c-axis to give tunable length up to centimeters with the assistance of tin,while the reported flat bulk ones with thickness are limited to micrometers.The as-produced needle-shaped violet phosphorus has also been demonstrated to significantly enhance the photocatalytic degradation of methyl orange pollutants due to its special crystallographic orientation.About 98.6%of methyl orange pollutants with a concentration of 50 ppm were degraded within 80 min under visible light conditions by needle-shaped violet phosphorus,which is much more effective than that of amorphous red phosphorus with only 14.1%degradation.展开更多
Resistive Random-Access Memory(ReRAM)based Processing-in-Memory(PIM)frameworks are proposed to accelerate the working process of DNN models by eliminating the data movement between the computing and memory units.To fu...Resistive Random-Access Memory(ReRAM)based Processing-in-Memory(PIM)frameworks are proposed to accelerate the working process of DNN models by eliminating the data movement between the computing and memory units.To further mitigate the space and energy consumption,DNN model weight sparsity and weight pattern repetition are exploited to optimize these ReRAM-based accelerators.However,most of these works only focus on one aspect of this software/hardware codesign framework and optimize them individually,which makes the design far from optimal.In this paper,we propose PRAP-PIM,which jointly exploits the weight sparsity and weight pattern repetition by using a weight pattern reusing aware pruning method.By relaxing the weight pattern reusing precondition,we propose a similarity-based weight pattern reusing method that can achieve a higher weight pattern reusing ratio.Experimental results show that PRAP-PIM achieves 1.64×performance improvement and 1.51×energy efficiency improvement in popular deep learning benchmarks,compared with the state-of-the-art ReRAM-based DNN accelerators.展开更多
Blue light-emitting polyfluorenes containing dibenzothiophene-S,S-dioxide(SO) unit in alkyl side chain(PF-FSOs and PF-CzSOs) were synthesized. All the polymers show high thermal stability with the decomposition temper...Blue light-emitting polyfluorenes containing dibenzothiophene-S,S-dioxide(SO) unit in alkyl side chain(PF-FSOs and PF-CzSOs) were synthesized. All the polymers show high thermal stability with the decomposition temperatures over400 °C. The highest occupied molecular orbital(HOMO) and the lowest unoccupied molecular orbital(LUMO) energy levels of the copolymer slightly decrease with the increase of SO content in side chain. PL spectra of the polymers show slightly red shift and broadening with the increase of solvent polarities, indicating unremarkable intramolecular charge transfer(ICT) effect in the polymers containing SO unit in alkyl side chain. EL spectra of the polymers are almost unchanged in the current densities from 100 to 400 mA cm.2, indicating the superb EL stability of the resulted polymers. The EL spectra of the copolymers exhibit obvious blue-shift and narrowing with the CIE of(0.18, 0.11) for PF-FSO10 and(0.17, 0.11) for PF-CzSO10, respectively,compared with PF-SO10 containing SO unit in main chain with the CIE of(0.16, 0.17) and PFO with the CIE of(0.18, 0.18).The superior device performances were obtained with the luminous efficiency(LEmax) of 1.17 and 0.68 cd A.1 for PF-FSO15 and PF-CzSO20, respectively, compared with the LEmax of 0.37 cd A.1 for PFO. The results indicate that linking SO unit to alkyl side chain of the polyfluorene is a promising strategy for efficient blue light-emitting polymers.展开更多
We described a novel single-cell RNA-seq technique called MR-seq(measure a single-cell transcriptome repeatedly),which permits statistically assessing the technical variation and identifying the differentially express...We described a novel single-cell RNA-seq technique called MR-seq(measure a single-cell transcriptome repeatedly),which permits statistically assessing the technical variation and identifying the differentially expressed genes between just two single cells by measuring each single cell twice. We demonstrated that MR-seq gave sensitivity and reproducibility similar to the standard single-cell RNA-seq and increased the positive predicate value. Application of MR-seq to early mouse embryos identified hundreds of candidate intra-embryonic heterogeneous genes among mouse 2-,4-and 8-cell stage embryos. MR-seq should be useful for detecting differentially expressed genes among a small number of cells.展开更多
Passive residual heat removal heat exchanger(PRHR HX),which is a newly designed equipment in the advanced reactors of AP1000 and CAP1400,plays an important role in critical accidental conditions.The primary and second...Passive residual heat removal heat exchanger(PRHR HX),which is a newly designed equipment in the advanced reactors of AP1000 and CAP1400,plays an important role in critical accidental conditions.The primary and secondary side coupling heat transfer characteristics of the passive residual heat removal system(PRHRS)determine the capacity to remove core decay heat during the accidents.Therefore,it is necessary to investigate the heat transfer characteristics and develop applicable heat transfer formulas for optimized design.In the present paper,an overall scaled-down natural circulation loop of PRHRS in AP1000,which comprises a scaleddown in-containment refueling water storage tank(IRWST)and PRHR HX models and a simulator of the reactor core,is built to simulate the natural circulation process in residual heat removal accidents.A series of experiments are conducted to study thermal-hydraulic behaviors in both sides of the miniaturized PRHR HX which is simulated by 12 symmetric arranged C-shape tubes.For the local PRHR HX heat transfer performance,traditional natural convection correlations for both the horizontal and vertical bundles are compared with the experimental data to validate their applicability for the specific heat transfer condition.Moreover,the revised natural convection heat transfer correlations based on the present experimental data are developed for PRHR HX vertical and lower horizontal bundles.This paper provides essential references for the PRHRS operation and further optimized design.展开更多
Power electronics,processing over 50%of world's electric energy,enables very efficient electric energy conversion for a wide range of applications such as electric vehicles,data centers,autonomous driving,robotics...Power electronics,processing over 50%of world's electric energy,enables very efficient electric energy conversion for a wide range of applications such as electric vehicles,data centers,autonomous driving,robotics and smart grids.The availability of low-cost,efficient,and reliable power semiconductor devices that can conduct high current,block high voltage,and switch at high frequencies are key to improving the performance of power electronics systems.展开更多
Congenital heart disease(CHD)is the most common of congenital cardiovascular malformations associated with birth defects,and it results in significant morbidity and mortality worldwide.The classification of CHD is sti...Congenital heart disease(CHD)is the most common of congenital cardiovascular malformations associated with birth defects,and it results in significant morbidity and mortality worldwide.The classification of CHD is still elusive owing to the complex pathogenesis of CHD.Advances in molecular medicine have revealed the genetic basis of some heart anomalies.Genes associated with CHD might be modulated by various epigenetic factors.Thus,the genetic and epigenetic factors are gradually accepted as important triggers in the pathogenesis of CHD.However,few literatures have comprehensively elaborated the genetic and epigenetic mechanisms of CHD.This review focuses on the etiology of CHD from genetics and epigenetics to discuss the role of these factors in the development of CHD.The interactions between genetic and epigenetic in the pathogenesis of CHD are also elaborated.Chromosome abnormalities and gene mutations in genetics,and DNA methylations,histone modifications and on-coding RNAs in epigenetics are summarized in detail.We hope the summative knowledge of these etiologies may be useful for improved diagnosis and further elucidation of CHD so that morbidity and mortality of children with CHD can be reduced in the near future.展开更多
Plant-originated natural products are important drug sources.However,total biosynthesis of these compounds is often not achievable due to their uncharacterized,lengthy biosynthetic pathways.In nature,phenethylisoquino...Plant-originated natural products are important drug sources.However,total biosynthesis of these compounds is often not achievable due to their uncharacterized,lengthy biosynthetic pathways.In nature,phenethylisoquinoline alkaloids(PIAs)such as colchicine are biosynthesized via a common precursor 6,7-dihydroxy-1-(4-hydroxyphenylethyl)-1,2,3,4-tetrahydroisoquinoline(i.e.,phenethylisoquinoline scaffold,PIAS).PIAS is naturally synthesized in plants by using two upstream substrates(L-phenylalanine and L-tyrosine)catalyzed by eight enzymes.To shorten this native pathway,here we designed an artificial route to synthesize PIAS with two enzymatic steps from two alternative substrates of 3-(4-hydroxyphenyl)propanol(4-HPP)and dopamine.In the two-step bioconversion,an alcohol dehydrogenase selected from yeast(i.e.,ADH7)was able to oxidize its non-native alcohol substrate 4-HPP to form the corresponding aldehyde product,which was then condensed with dopamine by the(S)-norcoclaurine synthase(NCS)to synthesize PIAS.After optimization,the final enzymatic reaction system was successfully scaled up by 200 times from 50μL to 10 mL,generating 5.4 mM of PIAS.We envision that this study will provide an easy and sustainable approach to produce PIAS and thus lay the foundation for large-scale production of PIAS-derived natural products.展开更多
基金supported by the National Key Research and Development Project of Chinathe National Natural Science Fund of China (Grant number 2018YFC1800403, 41571226)。
文摘The rapid development and widespread use of ZnO nanoparticles(nZnO) in various industries have raised concerns about their potential environmental impact.Therefore,understanding the fate and role of nZnO in the natural environment is crucial for mitigating their hazardous effects on the environment and human safety.The purpose of the present study was to provide scientific support for understanding and eliminating the joint risk of nanoparticle and heavy metal pollution in the soil environment by revealing the co-transport characteristics of Cd(Ⅱ) and ZnO nanoparticles(nZnO) in soil under different ionic strength(IS) and pH.The impacts of different IS and pH on the co-transport of Cd(Ⅱ) and nZnO in a20 cm long with an inner diameter of 2.5 cm acrylic column packed with 10 cm high soil samples were investigated in the present study.In the above system,a500 μg L^(-1) Cd(Ⅱ) loaded nZnO suspension pulse with varying IS or pH was introduced into the soil column for leaching over 5 PVs,followed up by 5 PVs background solutions without nZnO.The IS was 1,10,or 50 mM NaCl,with pH6,or the pH was 6,7 or 8 with 1 mM NaCl.Meanwhile,Sedimentation experiments for nZnO,adsorption of Cd(Ⅱ) on soil,and nZnO,DLVO theory calculation for the same background condition were conducted.The presence of nZnO significantly increased the mobility of Cd(Ⅱ) as a result of its strong adsorption capacity for nZnO-associated Cd(Ⅱ).However,with the increase of IS,the co-transport of nZnO and Cd(Ⅱ) was decreased and the retention of nZnO in the soil column due to more nZnO attended to aggregate and sediment during the transport and the decrease in the adsorption capacity of nZnO for Cd(Ⅱ) by competition of Na^(+).When pH was 6,7,and 8,the co-transport of nZnO and Cd(Ⅱ) increased with higher pH due to the lower electrostatic attraction between nZnO and soil under higher pH.Meanwhile,the DLVO theory was fitted to describe the above co-transport process of nZnO and Cd(Ⅱ).More attention should be paid to the presence of nZnO on the migration of Cd(Ⅱ) in the natural soil to control the potential risk of nanoparticles and heavy metals to the environment.The risk of co-transport of nZnO and Cd(Ⅱ) might be controlled by adjusting IS and pH in the soil solution.
基金granted by the National Key R&D Program of China (2021YFD21001005)National Natural Science Foundation of China (31972102,32101980)+1 种基金Special key project of Chongqing technology innovation and application development (cstc2021jscx-cylhX0014)Chongqing Technology Innovation and Application Development Special Project (cstc2021jscx-tpyzxX0014)。
文摘This study aimed to characterize and identify calcium-chelating peptides from rabbit bone collagen and explore the underlying chelating mechanism.Collagen peptides and calcium were extracted from rabbit bone by instant ejection steam explosion(ICSE)combined with enzymatic hydrolysis,followed by chelation reaction to prepare rabbit bone peptide-calcium chelate(RBCP-Ca).The chelating sites were further analyzed by liquid chromatography-tandem mass(LC-MS/MS)spectrometry while the chelating mechanism and binding modes were investigated.The structural characterization revealed that RBCP successfully chelated with calcium ions.Furthermore,LC-MS/MS analysis indicated that the binding sites included both acidic amino acids(Asp and Glu)and basic amino acids(Lys and Arg),Interestingly,three binding modes,namely Inter-Linking,Loop-Linking and Mono-Linking were for the first time found,while Inter-Linking mode accounted for the highest proportion(75.1%),suggesting that chelation of calcium ions frequently occurred between two peptides.Overall,this study provides a theoretical basis for the elucidation of chelation mechanism of calcium-chelating peptides.
基金the founding support from the National Natural Science Foundation of China(21906072 and 22006057)the Natural Science Foundation of Jiangsu Province(BK20190982)+2 种基金Henan Postdoctoral Foundation(202003013)“Doctor of Mass entrepreneurship and innovation” Project in Jiangsu ProvinceOpen Fund for Hebei Province Key Laboratory of Sustained Utilization & Development of Water Recourse(HSZYL2021003)。
文摘Photocatalysis is an environmentally friendly and energy-saving technology, which can effectively remove persistent dangerous pollutants in the water. Pitifully, optical absorption capacity and carrier separation have become major bottlenecks for marvelous photocatalytic performance of photocatalysts.Herein, to address these issue, Nanodiamonds/yolk-shell ZnFe_(2)O_(4) spheres(NDs/ZFO) nanocomposites were successfully constructed via a facile two-step of solvothermal and calcination methods. The synthesized optimal NDs/ZFO-10 nanocomposite exhibits superior photocatalytic degradation activity of antibiotic under visible light, approximately 85% of the total tetracycline(TC) is degraded, and this photocatalyst shows durable cycling stability. This stems from two aspects of refinement: improvement of light absorption capacity and photo-induced charges migration and separation. In addition, the NDs/ZFO composite photocatalyst features excellent magnetic recovery capability, facilitating the recovery of photocatalyst in industry. This study opens a new chapter in the combination of NDs with magnetic materials, and deepens the understanding of the application of NDs modified composite photocatalysts.
文摘There is currently great optimism within the electronics community that gallium oxide(Ga_(2)O_(3)) ultra-wide bandgap semiconductors have unprecedented prospects for eventually revolutionizing a rich variety of power electronic applications. Specially, benefiting from its ultra-high bandgap of around 4.8 eV, it is expected that the emerging Ga_(2)O_(3) technology would offer an exciting platform to deliver massively enhanced device performance for power electronics and even completely new applications.
文摘Gallium oxide(Ga_(2)O_(3))has garnered world-wide atten-tion as an ultrawide-bandgap semiconductor material from the area of power electronics and DUV optical devices benefit-ing from its outstanding electronic and optoelectronic proper-ties.For one thing,since Ga_(2)O_(3)features high critical break-down field of 8 MV/cm and Baliga’s figure of merit(BFOM)of 3444,it is a promising candidate for advanced high-power applications.For another thing,due to the bandgap directly corresponding to the deep-ultraviolet(DUV)region,Ga_(2)O_(3)is widely used in DUV optoelectronic devices.
基金supported by the National Key Research and Development Program of China(2020YFC0845400)National Natural Science Foundation of China(82141203,82304753)+2 种基金Innovation Team and Talents Cultivation Program of National Administration of Traditional Chinese Medicine(ZYYCXTD-D-202004)Shanghai Frontiers Science Center of TCM Chemical BiologyWe are very grateful to Professor Xiaolan Cui and her team from the China Academy of Chinese Medical Sciences for their support in animal models.
文摘Objective:Cold exposure has been suggested to be advantageous for the spread and infection of the coronavirus,and the gut microbiota influences the severity of the infection by modulating host inflammatory and immune responses.However,it remains unclear whether the promotion of viral infection through cold exposure is linked to the gut microbiota.Methods:In this study,we performed an unbiased analysis of gut microbiota,serum,and lung tissue metabolome changes in cold-exposed and virus-infected mice,alongside the assessment of immune-inflammatory indicators in serum and lung tissue.Results:The results revealed that both cold exposure and viral infection significantly decreased the percentage of peripheral blood lymphocytes(CD4^(+)T cells,CD8^(+)T cells,and B cell)and increased the expression of inflammatory factors(IL-6,IL-1β,TNF-α,and IFN-γ).Meanwhile,cold exposure disrupted the homeostasis of gut microbiota,elevating the abundance of pathogenic bacteria(Staphylococcus)and diminishing the abundance of beneficial bacteria(Alistipes).Notably,in virus-infected mice exposed to a cold environment,the reduction in the abundance of beneficial bacteria Alistipes was more pronounced than in cases of single virus infection and cold exposure.Analysis of altered serum and lung tissue metabolites highlighted glycerophospholipids,fatty acids,and eicosanoids as the most affected metabolites by cold exposure.These metabolites,closely associated with virus infection,exhibited a significant correlation with immune-inflammatory indicators.Conclusion:These findings establish a mechanistic connection between cold exposure and virus infection,suggesting that cold exposure-induced dysregulation of gut microbiota and lipid metabolism diminishes host immunity,promoting virus infection.
基金financially supported by National Key R&D Program of China(No.2016YFD0400200)National Natural Science Foundation of China(No.31972102,31671881,and 31901683)+4 种基金Chongqing Research Program of Basic Research and Frontier Technology(No.cstc2018jcyj A0939)Chongqing Technology Innovation and Application Demonstration Project(No.cstc2018jscx-msyb X0204)Fundamental Research Funds for the Central Universities(No.XDJK2019B028)Innovation Program for Chongqing’s Overseas Returnees(cx2019072)Fundamental Research Funds for the Central Universities,China(SWU 019009)。
文摘Ultraviolet(UV)-induced photoaging skin has become an urgent issue.The functional foods and cosmetics aiming to improve skin photoaging are developing rapidly,and the demand is gradually increasing year by year.Collagen peptides have been proven to display diverse physiological activities,such as excellent moisture retention activity,hygroscopicity,tyrosinase inhibitory activity and antioxidant activity,which indicates that they have great potential in amelioration of UV-induced photoaging.The main objective of this article is to recap the main mechanisms to improve photoaging skin by collagen peptides and their physiological activities in photo-protection.Furthermore,the extraction and structural characteristics of collagen peptides are overviewed.More importantly,some clinical trials on the beneficial effect on skin of collagen peptides are also discussed.In addition,prospects and challenges of collagen peptides are emphatically elucidated in this review.This article implies that collagen peptides have great potential as an effective ingredient in food and cosmetics industry with a wide application prospect.
基金supported by the Jiangsu Province“333”project BRA2020418the NSFC under Grant Number 71901215+2 种基金the National University of Defense Technology Research Project ZK20-46the Outstanding Young Talents Program of National University of Defense Technologythe National University of Defense Technology Youth Innovation Project。
文摘The joint extraction of entities and their relations from certain texts plays a significant role in most natural language processes.For entity and relation extraction in a specific domain,we propose a hybrid neural framework consisting of two parts:a span-based model and a graph-based model.The span-based model can tackle overlapping problems compared with BILOU methods,whereas the graph-based model treats relation prediction as graph classification.Our main contribution is to incorporate external lexical and syntactic knowledge of a specific domain,such as domain dictionaries and dependency structures from texts,into end-to-end neural models.We conducted extensive experiments on a Chinese military entity and relation extraction corpus.The results show that the proposed framework outperforms the baselines with better performance in terms of entity and relation prediction.The proposed method provides insight into problems with the joint extraction of entities and their relations.
基金support for this research is from the National Natural Science Foundation of China(No.22175136)Fundamental Research Funds for the Central Universities.
文摘The control of crystal growth is important but challenging for multi-disciplinary research.Violet phosphorus,the most stable phosphorus allotrope,has recently been produced as a unique semiconducting layered structure.The crystal orientation and morphology bring extra performance due to its unique structure and anisotropy.Herein,the layered violet phosphorus has been controlled to grow along the c-axis to give tunable length up to centimeters with the assistance of tin,while the reported flat bulk ones with thickness are limited to micrometers.The as-produced needle-shaped violet phosphorus has also been demonstrated to significantly enhance the photocatalytic degradation of methyl orange pollutants due to its special crystallographic orientation.About 98.6%of methyl orange pollutants with a concentration of 50 ppm were degraded within 80 min under visible light conditions by needle-shaped violet phosphorus,which is much more effective than that of amorphous red phosphorus with only 14.1%degradation.
基金partially supported by the National Natural Science Foundation of China(92064008)the CCF-Huawei Huyanglin Project CCF-HuaweiST2021002+1 种基金the Open Project Program of Wuhan National Laboratory for Optoelectronics(2022WNLOKF018)the Shandong Provincial Natural Science Foundation(ZR2022LZH010).
文摘Resistive Random-Access Memory(ReRAM)based Processing-in-Memory(PIM)frameworks are proposed to accelerate the working process of DNN models by eliminating the data movement between the computing and memory units.To further mitigate the space and energy consumption,DNN model weight sparsity and weight pattern repetition are exploited to optimize these ReRAM-based accelerators.However,most of these works only focus on one aspect of this software/hardware codesign framework and optimize them individually,which makes the design far from optimal.In this paper,we propose PRAP-PIM,which jointly exploits the weight sparsity and weight pattern repetition by using a weight pattern reusing aware pruning method.By relaxing the weight pattern reusing precondition,we propose a similarity-based weight pattern reusing method that can achieve a higher weight pattern reusing ratio.Experimental results show that PRAP-PIM achieves 1.64×performance improvement and 1.51×energy efficiency improvement in popular deep learning benchmarks,compared with the state-of-the-art ReRAM-based DNN accelerators.
基金supported by the National Key Basic Research and Development Program of China (2015CB655004)the National Natural Science Foundation of China (51473054, 91333206)the Fundamental Research Funds for the Central Universities, South China of Technology (2017MS020)
文摘Blue light-emitting polyfluorenes containing dibenzothiophene-S,S-dioxide(SO) unit in alkyl side chain(PF-FSOs and PF-CzSOs) were synthesized. All the polymers show high thermal stability with the decomposition temperatures over400 °C. The highest occupied molecular orbital(HOMO) and the lowest unoccupied molecular orbital(LUMO) energy levels of the copolymer slightly decrease with the increase of SO content in side chain. PL spectra of the polymers show slightly red shift and broadening with the increase of solvent polarities, indicating unremarkable intramolecular charge transfer(ICT) effect in the polymers containing SO unit in alkyl side chain. EL spectra of the polymers are almost unchanged in the current densities from 100 to 400 mA cm.2, indicating the superb EL stability of the resulted polymers. The EL spectra of the copolymers exhibit obvious blue-shift and narrowing with the CIE of(0.18, 0.11) for PF-FSO10 and(0.17, 0.11) for PF-CzSO10, respectively,compared with PF-SO10 containing SO unit in main chain with the CIE of(0.16, 0.17) and PFO with the CIE of(0.18, 0.18).The superior device performances were obtained with the luminous efficiency(LEmax) of 1.17 and 0.68 cd A.1 for PF-FSO15 and PF-CzSO20, respectively, compared with the LEmax of 0.37 cd A.1 for PFO. The results indicate that linking SO unit to alkyl side chain of the polyfluorene is a promising strategy for efficient blue light-emitting polymers.
基金supported by grants from the Beijing Municipal Science and Technology Commission (D15110700240000)
文摘We described a novel single-cell RNA-seq technique called MR-seq(measure a single-cell transcriptome repeatedly),which permits statistically assessing the technical variation and identifying the differentially expressed genes between just two single cells by measuring each single cell twice. We demonstrated that MR-seq gave sensitivity and reproducibility similar to the standard single-cell RNA-seq and increased the positive predicate value. Application of MR-seq to early mouse embryos identified hundreds of candidate intra-embryonic heterogeneous genes among mouse 2-,4-and 8-cell stage embryos. MR-seq should be useful for detecting differentially expressed genes among a small number of cells.
基金the National Science and Technology Major Project of China(Grant No.2017ZX06004002-006-002)the National Natural Science Foundation of China(Grant No.51906069)。
文摘Passive residual heat removal heat exchanger(PRHR HX),which is a newly designed equipment in the advanced reactors of AP1000 and CAP1400,plays an important role in critical accidental conditions.The primary and secondary side coupling heat transfer characteristics of the passive residual heat removal system(PRHRS)determine the capacity to remove core decay heat during the accidents.Therefore,it is necessary to investigate the heat transfer characteristics and develop applicable heat transfer formulas for optimized design.In the present paper,an overall scaled-down natural circulation loop of PRHRS in AP1000,which comprises a scaleddown in-containment refueling water storage tank(IRWST)and PRHR HX models and a simulator of the reactor core,is built to simulate the natural circulation process in residual heat removal accidents.A series of experiments are conducted to study thermal-hydraulic behaviors in both sides of the miniaturized PRHR HX which is simulated by 12 symmetric arranged C-shape tubes.For the local PRHR HX heat transfer performance,traditional natural convection correlations for both the horizontal and vertical bundles are compared with the experimental data to validate their applicability for the specific heat transfer condition.Moreover,the revised natural convection heat transfer correlations based on the present experimental data are developed for PRHR HX vertical and lower horizontal bundles.This paper provides essential references for the PRHRS operation and further optimized design.
文摘Power electronics,processing over 50%of world's electric energy,enables very efficient electric energy conversion for a wide range of applications such as electric vehicles,data centers,autonomous driving,robotics and smart grids.The availability of low-cost,efficient,and reliable power semiconductor devices that can conduct high current,block high voltage,and switch at high frequencies are key to improving the performance of power electronics systems.
基金supported by the National Key R&D Program of China(grant number 2018YFC1002700)the National Key R&D Program of China(grant number 2018YFC1002703).
文摘Congenital heart disease(CHD)is the most common of congenital cardiovascular malformations associated with birth defects,and it results in significant morbidity and mortality worldwide.The classification of CHD is still elusive owing to the complex pathogenesis of CHD.Advances in molecular medicine have revealed the genetic basis of some heart anomalies.Genes associated with CHD might be modulated by various epigenetic factors.Thus,the genetic and epigenetic factors are gradually accepted as important triggers in the pathogenesis of CHD.However,few literatures have comprehensively elaborated the genetic and epigenetic mechanisms of CHD.This review focuses on the etiology of CHD from genetics and epigenetics to discuss the role of these factors in the development of CHD.The interactions between genetic and epigenetic in the pathogenesis of CHD are also elaborated.Chromosome abnormalities and gene mutations in genetics,and DNA methylations,histone modifications and on-coding RNAs in epigenetics are summarized in detail.We hope the summative knowledge of these etiologies may be useful for improved diagnosis and further elucidation of CHD so that morbidity and mortality of children with CHD can be reduced in the near future.
基金supported by grants from the National Natural Science Foundation of China(32171427 and 31971348)。
文摘Plant-originated natural products are important drug sources.However,total biosynthesis of these compounds is often not achievable due to their uncharacterized,lengthy biosynthetic pathways.In nature,phenethylisoquinoline alkaloids(PIAs)such as colchicine are biosynthesized via a common precursor 6,7-dihydroxy-1-(4-hydroxyphenylethyl)-1,2,3,4-tetrahydroisoquinoline(i.e.,phenethylisoquinoline scaffold,PIAS).PIAS is naturally synthesized in plants by using two upstream substrates(L-phenylalanine and L-tyrosine)catalyzed by eight enzymes.To shorten this native pathway,here we designed an artificial route to synthesize PIAS with two enzymatic steps from two alternative substrates of 3-(4-hydroxyphenyl)propanol(4-HPP)and dopamine.In the two-step bioconversion,an alcohol dehydrogenase selected from yeast(i.e.,ADH7)was able to oxidize its non-native alcohol substrate 4-HPP to form the corresponding aldehyde product,which was then condensed with dopamine by the(S)-norcoclaurine synthase(NCS)to synthesize PIAS.After optimization,the final enzymatic reaction system was successfully scaled up by 200 times from 50μL to 10 mL,generating 5.4 mM of PIAS.We envision that this study will provide an easy and sustainable approach to produce PIAS and thus lay the foundation for large-scale production of PIAS-derived natural products.
