Dietary anthocyanins are important health-promoting antioxidants that make a major contribution to the quality of fruits. It is intriguing that most tomato cultivars do not produce anthocyanins in fruit. However, the ...Dietary anthocyanins are important health-promoting antioxidants that make a major contribution to the quality of fruits. It is intriguing that most tomato cultivars do not produce anthocyanins in fruit. However, the purple tomato variety Indigo Rose, which has the dominant Aft locus combined with the recessive atv locus from wild tomato species, exhibits light-dependent anthocyanin accumulation in the fruit skin. Here, we report that Aft encodes a functional anthocyanin activator named SlAN2-like, while atv encodes a nonfunctional version of the anthocyanin repressor SlMYBATV. The expression of SlAN2-like is responsive to light, and the functional SlAN2-like can activate the expression of both anthocyanin biosynthetic genes and their regulatory genes, suggesting that SlAN2-like acts as a master regulator in the activation of anthocyanin biosynthesis. We further showed that cultivated tomatoes contain nonfunctional alleles of SlAN2-like and therefore fail to produce anthocyanins. Consistently, expression of a functional SlAN2-like gene driven by the fruit-specific promoter in a tomato cultivar led to the activation of the entire anthocyanin biosynthesis pathway and high-level accumulation of anthocyanins in both the peel and flesh. Taken together, our study exemplifies that efficient engineering of complex metabolic pathways could be achieved through tissue-specific expression of master transcriptional regulators.展开更多
With the ever-pressing issues of global energy demand and environmental pollution,molecular hydrogen has been receiving increasing attention as a clean alternative energy carrier.For hydrogen production,the design and...With the ever-pressing issues of global energy demand and environmental pollution,molecular hydrogen has been receiving increasing attention as a clean alternative energy carrier.For hydrogen production,the design and development of high-performance catalysts remains rather challenging.As the compositions and structures of catalyst interfaces have paramount influences on the catalytic performances,the central topic here has always been to design and engineer the interface structures via rational routes so as to boost the activities and stabilities of electrocatalysts on hydrogen evolution reaction(HER).Here in this review,we focus on the design and preparation of multi-scale catalysts specifically catering to HER applications.We start from the design and structure-activity relationship of catalytic nanostructures,summarize the research progresses related to HER nanocatalysts,and interpret their high activities from the atomistic perspective;then,we review the studies regarding the design,preparation,HER applications and structure-activity relationship of single-atom site catalysts(SASCs),and thereupon discuss the future directions in designing HER-oriented SASCs.At the end of this review,we present an outlook on the development trends and faced challenges of catalysts for electrochemical HER.展开更多
When material dimensions are reduced to the nanoscale,exceptional physical mechanics properties can be obtained that differ significantly from the corresponding bulk materials.Here we review the physical mechanics of ...When material dimensions are reduced to the nanoscale,exceptional physical mechanics properties can be obtained that differ significantly from the corresponding bulk materials.Here we review the physical mechanics of the friction of low‐dimensional nanomaterials,including zero‐dimensional nanoparticles,one‐dimensional multiwalled nanotubes and nanowires,and two‐dimensional nanomaterials-such as graphene,hexagonal boron nitride(h‐BN),and transition‐metal dichalcogenides-as well as topological insulators.Nanoparticles between solid surfaces can serve as rolling and sliding lubrication,while the interlayer friction of multiwalled nanotubes can be ultralow or significantly high and sensitive to interwall spacing and chirality matching,as well as the tube materials.The interwall friction can be several orders of magnitude higher in binary polarized h‐BN tubes than in carbon nanotubes mainly because of wall buckling.Furthermore,current extensive studies on two‐dimensional nanomaterials are comprehensively reviewed herein.In contrast to their bulk materials that serve as traditional dry lubricants(e.g.,graphite,bulk h‐BN,and MoS_(2)),large‐area high‐quality monolayered two‐dimensional nanomaterials can serve as single‐atom‐thick coatings that minimize friction and wear.In addition,by appropriately tuning the surface properties,these materials have shown great promise for creating energy‐efficient self‐powered electro‐opto‐magneto‐mechanical nanosystems.State‐of‐the‐art experimental and theoretical methods to characterize friction in nanomaterials are also introduced.展开更多
Tomato (Solanum lycopersicum) is the leading vegetable crop worldwide and an essential component of a healthy diet (Lin et al., 2014; Du et al., 2017). Fruit color is regarded as one of the most important commerci...Tomato (Solanum lycopersicum) is the leading vegetable crop worldwide and an essential component of a healthy diet (Lin et al., 2014; Du et al., 2017). Fruit color is regarded as one of the most important commercial traits in tomato (The Tomato Genome Consortium, 2012). Consumers in different regions have different color preferences. For example, European and American consumers prefer red tomatoes, while pink tomatoes are more pop- ular in Asia countries, particularly in China and Japan (Ballester et al., 2010; Lin et al., 2014). However, most of tomato breeding ma- terials are red-fruited, thus the generation of pink-fruited materials is very important for Asian tomato production. Metabolomics and genetics studies demonstrate that the pink trait results from the absence of yellow-colored flavonoid naringenin chalcone (NarCh) in the peels,展开更多
Dear Editor Pepper belongs to the Solanaceae family, which includes many important vegetable crops such as tomato, potato, and eggplant. Not only widely used as vegetables and spicy ingredients, pepper also has divers...Dear Editor Pepper belongs to the Solanaceae family, which includes many important vegetable crops such as tomato, potato, and eggplant. Not only widely used as vegetables and spicy ingredients, pepper also has diverse applications in pharmaceutics, natural coloring agents, cosmetics, defense repellents, and as ornamental plants (Kim et al., 2014; Qin et al., 2014). Pepper is among the most widely cultivated and consumed vegetables in the world, with annual production reachincl to 38 million tons in 2011 (www.fao.展开更多
Intrauterine adhesion(IUA) is a common cause of uterine infertility and one of the most severe clinical features is endometrial fibrosis namely endometrial scarring for which there are few cures currently. Blocked ang...Intrauterine adhesion(IUA) is a common cause of uterine infertility and one of the most severe clinical features is endometrial fibrosis namely endometrial scarring for which there are few cures currently. Blocked angiogenesis is the main pathological change in the scarred endometrium. The fibroblast growth factor 2(b FGF), a member of FGF family, is usually applied to promote healing of refractory ulcer and contributes to angiogenesis of tissues. In this study, the sustained-release system of b FGF100 μg was administrated around scarred endometrium guiding by ultrasound every 4 weeks in 18 patients(2–4 times). Results showed that after treatment, the menstrual blood volume, endometrial thickness and the scarred endometrial area were improved.Histological study showed blood vessel density increased obviously. Three patients(3/18) achieved pregnancy over 20 gestational weeks. Therefore, administrating the b FGF surrounding scarred endometrium may provide a new therapeutic approach for the patients with endometrial fibrosis.展开更多
Nickel-rich cathode materials have attracted considerable interest because of their high specific capacities,voltage ranges,and low cost.However,serious capacity attenuation and poor rate performance limit their appli...Nickel-rich cathode materials have attracted considerable interest because of their high specific capacities,voltage ranges,and low cost.However,serious capacity attenuation and poor rate performance limit their application.This study proposes a novel strategy to improve the cycle stability of the nickel-rich LiNi0.sCo0.1Mn0.1O2(NCM811)layer material by designing core-shell LiNio.sCoo.1 Mno.102(CS-NCM811).CS-NCM811 is designed by the characteristic reaction between dimethylglyoxime(C4H8N2O2)and nickel ion to form Ni(C4H7N2O2)2-The CS-NCM811 is characterized with high nickel content in its core and high manganese content on its surface,leading to a high capacity and excellent cycle stability.The capacity retention of CS-NCM811 was 72.8%,much higher than that of NCM811(47.1%)after 500 cycles at a rate of 5 C.Not only is this method a no vel strategy to desig n high capacity cathode materials but also provides some new in sights into the cycle stability of nickel-rich layered cathode materials.展开更多
We analyzed the deformation characteristics of overlying stratum in backfilling with fully-mechanized and retaining roadways along the gob area coal mining technology, and established a mechanical model for the roof k...We analyzed the deformation characteristics of overlying stratum in backfilling with fully-mechanized and retaining roadways along the gob area coal mining technology, and established a mechanical model for the roof key stratum of retaining roadways along gob under the conditions of backfilling and fully- mechanized coal mining technology. Using Winkler elastic foundation theory, we analyzed a part of the key stratum under the action of elastic foundation coupling problem, and derived deflection analyt- ical expressions. Combined with specific conditions, we obtained the deflection curves for the roof key stratum of retaining roadways along gob under the conditions of backfilling and fully-mechanized coal mining technology. On this basis, we adopted the Coulomb's earth pressure theory to solve the problem of lateral pressure of the gangue filling area on the supporting wall beside the roadway and to provide the theoretical basis for reasonable selection of the distance between gangue concrete wall and roof and fur- ther discussion on the supporting stability of roadway.展开更多
The expression of FOAl (F-box overexpressed/oppressed ABA signaling) in different organs of Arabidopsis, and in response to ABA and NaCI, was analyzed. The expression level of FOAl is higher in the root and is lower...The expression of FOAl (F-box overexpressed/oppressed ABA signaling) in different organs of Arabidopsis, and in response to ABA and NaCI, was analyzed. The expression level of FOAl is higher in the root and is lower in the stem, and is induced rapidly by ABA and NaC1. The phenotypes of T-DNA insertion mutant foal and FOAl overexpression lines FOAloxl and FOAlox2 were analyzed. The foal mutant exhibited a lower germination rate, shorter root length, more stomatal opening, in- creased proline accumulation and hypersensitivity to ABA compared with the wild type. In contrast, the overexpression lines showed lower sensitivity to ABA than the wild type. The expression levels of several ABA and stress-responsive transcription factors and genes were altered in the foal mutant in response to ABA. Compared with the wild type, the expression levels of ABA-responsive transcription factors were higher, but ABA and stress-responsive genes were lower in foal mutant. This study demonstrates that FOAl is an ABA signaling-related gene, and may play a negative role in ABA signaling.展开更多
Flexible supercapacitors are promising energy storage devices in wearable smart electronics. Exploring cost-efficient electrodes with high capacitance would promote the wide-scale application of such capacitors. Herei...Flexible supercapacitors are promising energy storage devices in wearable smart electronics. Exploring cost-efficient electrodes with high capacitance would promote the wide-scale application of such capacitors. Herein, in order to explore a methodology for preparing low cost, flexible, tough, and up-scalable supercapacitor electrodes, silk textile is directly carbonized to make a conductive free-standing textile substrate. Through mildly baking the surfactant-free TiCTflakes suspension loaded on the carbonized silk cloth, a uniform and adhesive coating consisting of nanometer-thick TiCTflakes is well established on the conductive fabric support, forming a MXene-coated flexible textile electrode. The fabricated electrode exhibits a high areal capacitance of 362 m F/cm~2 with excellent cyclability and flexibility. Moreover,capacitance changes neglegibly under the bending deformation mode. This study elucidates the feasibility of using silk-derived carbon cloth from biomss for MXene-based flexible supercapacitor.展开更多
Pollen tube growth is crucial for successful fertilization.In Arabidopsis thaliana,the ANXUR(ANX)/BUPS receptor kinase complex controls and maintains pollen tube growth in response to autocrine rapid alkalin-ization f...Pollen tube growth is crucial for successful fertilization.In Arabidopsis thaliana,the ANXUR(ANX)/BUPS receptor kinase complex controls and maintains pollen tube growth in response to autocrine rapid alkalin-ization factor 4/19(RALF4/19)signaling;however,the molecular and cellular mechanisms underlying the ANX/BUPS-mediated regulation of pollen tube growth remain unclear.In this study,we found that pollen-specific LORELEI-like GPI-anchored proteins 2 and 3(LLG2/3)promote pollen tube growth in vitro and in vivo.LLG2/3 interacte with ANX/BUPS in a RALF4-concentration-dependent manner,suggesting that ANX/BUPS and LLG2/3 might form a receptor-coreceptor complex for perceiving RALF peptide signals.Disruption of the ANX/BUPS-LLG2/3 interaction led to the cytoplasmic retention of ANX1/2,in either llg2/3 knockdown mutants or in anx1/2 mutants lacking the J region,which mediates the ANX/BUPS-LLG2/3 interaction.Moreover,we found that RALF4 induced the production of reactive oxygen species(ROS),which stimulate pollen tube growth and reduce pollen burst rate.ROS levels are reduced in the pollen tubes of LLG2/3 RNAi lines,and application of exogenous H2O2 could partially rescue the defective pollen tube growth of LLG2/3 RNAi lines.Taken together,our study identifies LLG2/3 as novel regulatory components of pollen tube growth,and shows that they chaperone ANX/BUPS for secretion to the apical plasma membrane of pollen tube and act as coreceptors of ANX/BUPS in the acti-vation of ROS production for promoting pollen tube growth.展开更多
To the Editor:In sepsis,bacterial endotoxins play a central role by inducing a dysregulated and exaggerated release of inflammatory mediators and cytokines,often described as the“cytokine storm”or“cytokinemia.”[1]...To the Editor:In sepsis,bacterial endotoxins play a central role by inducing a dysregulated and exaggerated release of inflammatory mediators and cytokines,often described as the“cytokine storm”or“cytokinemia.”[1]Both endotoxins and cytokines have been implicated in the development of organ dysfunction,including acute kidney injury(AKI).[2]Removing circulating endotoxins and excess cytokines from the circulation restores chemotactic gradients,localizing the immune response to the principal site of infection and re-establishing a regulated immune response.[1,3]Therefore,using hemofilters with enhanced endotoxin and cytokine adsorptive properties may bring about additional therapeutic benefits compared with conventional continuous renal replacement therapy(CRRT)filters.展开更多
This paper focused on the pollution characteristics, sources and lung cancer risk of atmospheric polycyclic aromatic hydrocarbons (PAHs) in a new urban district of Nanjing, China. Gaseous and aerosol PM2.5 (particu...This paper focused on the pollution characteristics, sources and lung cancer risk of atmospheric polycyclic aromatic hydrocarbons (PAHs) in a new urban district of Nanjing, China. Gaseous and aerosol PM2.5 (particulate matter with aerodynamic diameter smaller than 2.S μm) samples were collected in spring of 2015. Sixteen PAHs were extracted and analyzed after sampling. Firstly, arithmetic mean concentrations of PAHs and BaPeq (benzo[a]pyrene equivalent) were calculated. The mean concentrations of PAHs were 29.26 ± 14.13,18.14 ± 5.37 and 48.47 ± 16.03 ng/m3 in gas phase, particle phase and both phases, respectively. The mean concentrations of BaPeq were 0.87 ± 0.51, 2.71 ± 2.17 and 4.06 ± 2.31 ng/m3 in gas phase, particle phase and both phases, respectively. Secondly, diagnostic ratios and principal component analysis were adopted to identify the sources of PAHs and the outcomes were the same: traffic exhaust was the predominant source followed by fuel combustion and industrial process. Finally, incremental lung cancer risk (ILCR) induced by whole year inhalation exposure to PAHs for population groups of different age and gender were estimated based on a Monte Carlo simulation. ILCR values caused by particle phase PAHs were greater than those caused by gas phase PAHs. ILCR values for adults were greater than those for other age groups. ILCR values caused by total (gas + particle) PAHs for diverse groups were all greater than the significant level (10-6), indicating high potential lung cancer risk. Sensitivity analysis results showed that cancer slope factor for BaP inhalation exposure and BaPeq concentration had greater impact than body weight and inhalation rate on the ILCR.展开更多
Ferritin,an iron-storage protein,regulates cellular iron metabolism and oxidative stress.The ferritin structure is characterized as a spherical cage,inside which large amounts of iron are deposited in a safe,compact a...Ferritin,an iron-storage protein,regulates cellular iron metabolism and oxidative stress.The ferritin structure is characterized as a spherical cage,inside which large amounts of iron are deposited in a safe,compact and bioavailable form.All ferritins readily catalyze Fe(II)oxidation by peroxides at the ferroxidase center to prevent free Fe(II)from participating in oxygen free radical formation via Fenton chemistry.Thus,ferritin is generally recognized as a cytoprotective stratagem against intracellular oxidative damage.The expression of cytosolic ferritins is usually regulated by iron status and oxidative stress at both the transcriptional and post-transcriptional levels.The mechanism of ferritin-mediated iron recycling is far from clarified,though nuclear receptor co-activator 4(NCOA4)was recently identified as a cargo receptor for ferritin-based lysosomal degradation.Cytosolic ferritins are heteropolymers assembled by H-and L-chains in different proportions.The mitochondrial ferritins are homopolymers and distributed in restricted tissues.They play protective roles in mitochondria where heme-and Fe/S-enzymes are synthesized and high levels of ROS are produced.Genetic ferritin disorders are mainly related to the L-chain mutations,which generally cause severe movement diseases.This review is focused on the biochemistry and function of mammalian intracellular ferritin as the major iron-storage and anti-oxidation protein.展开更多
Although one-dimensional Pt nanocrystals have long been regarded as ideal electrode catalysts for fuel cells,the synthetic techniques commonly involve the use of various complicated templates or surfactants,which have...Although one-dimensional Pt nanocrystals have long been regarded as ideal electrode catalysts for fuel cells,the synthetic techniques commonly involve the use of various complicated templates or surfactants,which have largely hampered their large-scale industrial application.Herein,we present a convenient and cost-effective approach to the stereoassembly of quasi-one-dimensional grain boundary-enriched Pt nanoworms on nitrogen-doped low-defect graphitic carbon nanosheets(Pt NWs/NL-CNS).Benefiting from its numerous catalytically active grain boundaries as well as optimized electronic structure,the as-derived Pt NWs/NL-CNS catalyst possesses exceptionally good electrocatalytic properties for methanol oxidation,including an ultrahigh mass activity of 1949.5 mA mg^(-1), reliable long-term durability,and strong poison tolerance,affording one of the most active Pt-based electrocatalysts for methanol oxidation reaction.Density functional theory calculation further reveals that the formation of worm-shape Pt morphology is attributed to the modified electronic structure as well as controllable defect density of the carbon matrix,which could also weaken the adsorption ability of Pt towards CO molecule and meanwhile synergistically promotes the catalytic reaction kinetics.展开更多
Nanozymes are nanomaterials with enzyme-like properties that have attracted significant interest owing to their capability to address the limitations of traditional enzymes such as fragility,high cost,and impossible m...Nanozymes are nanomaterials with enzyme-like properties that have attracted significant interest owing to their capability to address the limitations of traditional enzymes such as fragility,high cost,and impossible mass production.Over the past decade,a broad variety of nanomaterials have been found to mimic the enzyme-like activity by engineering the active centers of natural enzymes or developing multivalent elements within nanostructures.Carbon nanomaterials with well-defined electronic and geometric structures have served as favorable surrogates of traditional enzymes by mimicking the highly evolved catalytic center of natural enzymes.In particular,by combining the unique electronic,optical,thermal,and mechanical properties,carbon nanomaterials-based nanozymes can offer a variety of multifunctional platforms for biomedical applications.In this review,we will introduce the enzymatic characteristics and recent advances of carbon nanozymes,and summarize their significant applications in biomedicine.展开更多
During criminal case investigations,blood evidence tracing is critical for criminal investigation.However,the blood stains are often cleaned or covered up after the crime,resulting in trace residue and difficult track...During criminal case investigations,blood evidence tracing is critical for criminal investigation.However,the blood stains are often cleaned or covered up after the crime,resulting in trace residue and difficult tracking.Therefore,a highly sensitive and specific method for the rapid detection of human blood stains remains urgent.To solve this problem,we established a nanozyme-based strip for rapid detection of blood evidence with high sensitivity and specificity.To construct reliable nanozyme strips,we synthesized CoFe_(2)O_(4) nanozymes with high peroxidase-like activity by scaling up to gram level,which can be supplied for six million tests,and conjugated antibody as a detection probe in nanozyme strip.The developed CoFe_(2)O_(4) nanozyme strip can detect human hemoglobin(HGB)at a concentration as low as 1 ng/mL,which is 100 times lower than the commercially available colloidal gold strips(100 ng/mL).Moreover,this CoFe_(2)O_(4) nanozyme strip showed high generality on 12 substrates and high specificity to human HGB among 13 animal blood samples.Finally,we applied the developed CoFe_(2)O_(4) nanozyme strip to successfully detect blood stains in three real cases,where the current commercial colloidal gold strip failed to do.The results suggest that the CoFe_(2)O_(4) nanozyme strip can be used as an effective on-scene detection method for human blood stains,and can further be used as a long-term preserved material evidence for traceability inquiry.展开更多
Plant receptor-like protein kinases(RLKs) are transmembrane proteins with an extracellular domain and an intracellular kinase domain, which enable plant perceiving diverse extracellular stimuli to trigger the intracel...Plant receptor-like protein kinases(RLKs) are transmembrane proteins with an extracellular domain and an intracellular kinase domain, which enable plant perceiving diverse extracellular stimuli to trigger the intracellular signal transduction. The somatic embryogenesis receptor kinases(SERKs) code the leucine-rich-repeat receptor-like kinase(LRR-RLK), and have been demonstrated to associate with multiple ligand-binding receptors to regulate plant growth, root development, male fertility, stomatal development and movement, and immune responses. Here, we focus on the progress made in recent years in understanding the versatile functions of Arabidopsis SERK proteins, and review SERK proteins as co-receptor to perceive different endogenous and environmental cues in different signaling pathway, and discuss how the kinase activity of SERKs is regulated by various modification.展开更多
Type 1 diabetes mellitus is heterogeneous in many facets. The patients suffered from type 1 diabetes present several levels of islet function as well as variable number and type of islet-specific autoantibodies. This ...Type 1 diabetes mellitus is heterogeneous in many facets. The patients suffered from type 1 diabetes present several levels of islet function as well as variable number and type of islet-specific autoantibodies. This study was to investigate prevalence and heterogeneity of the islet autoantibodies and clinical phenotypes of type 1 diabetes mellitus; and also discussed the process of islet failure and its risk factors in Chinese type 1 diabetic patients. A total of 1,291 type 1 diabetic patients were enrolled in this study. Demographic information was collected. Laboratory tests including mixed-meal tolerance test, human leukocyte antigen alleles, hemoglobin A1 c, lipids, thyroid function and islet autoantibodies were conducted. The frequency of islet-specific autoantibody in newly diagnosed T1 DM patients(duration shorter than half year) was 73% in East China. According to binary logistic regressions, autoantibody positivity, longer duration and lower Body Mass Index were the risk factors of islet failure. As the disease developed, autoantibodies against glutamic acid decarboxylase declined as well as the other two autoantibodies against zinc transporter 8 and islet antigen 2. The decrease of autoantibodies was positively correlated with aggressive beta cell destruction. Autoantibodies can facilitate the identification of classic T1 DM from other subtypes and predict the progression of islet failure. As there were obvious heterogeneity in autoantibodies and clinical manifestation in different phenotypes of the disease, we should take more factors into consideration when identifying type 1 diabetes mellitus.展开更多
基金This work was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences,China(XDA24020308)the National Key Research and Development Program of China,China(2016YFD0100500)+1 种基金the Ministry of Agriculture of China,China(2016ZX08009-003-001)he Tai-Shan Scholar Program from Shandong Province(No.tsxk20150901).
文摘Dietary anthocyanins are important health-promoting antioxidants that make a major contribution to the quality of fruits. It is intriguing that most tomato cultivars do not produce anthocyanins in fruit. However, the purple tomato variety Indigo Rose, which has the dominant Aft locus combined with the recessive atv locus from wild tomato species, exhibits light-dependent anthocyanin accumulation in the fruit skin. Here, we report that Aft encodes a functional anthocyanin activator named SlAN2-like, while atv encodes a nonfunctional version of the anthocyanin repressor SlMYBATV. The expression of SlAN2-like is responsive to light, and the functional SlAN2-like can activate the expression of both anthocyanin biosynthetic genes and their regulatory genes, suggesting that SlAN2-like acts as a master regulator in the activation of anthocyanin biosynthesis. We further showed that cultivated tomatoes contain nonfunctional alleles of SlAN2-like and therefore fail to produce anthocyanins. Consistently, expression of a functional SlAN2-like gene driven by the fruit-specific promoter in a tomato cultivar led to the activation of the entire anthocyanin biosynthesis pathway and high-level accumulation of anthocyanins in both the peel and flesh. Taken together, our study exemplifies that efficient engineering of complex metabolic pathways could be achieved through tissue-specific expression of master transcriptional regulators.
基金Acknowledgements This work was supported by the National Key R&D Program of China(2016YFA0202801,2017YFA0700101 and 2018YFA0702003)the National Natural Science Foundation of China(21925202,21872076 and 21890383)+4 种基金Beijing Natural Science Foundation(JQ18007)the Fundamental Research Funds for the Central Universities(19CX02008A)the Petro China Innovation Foundation(2019D-5007-0401)Taishan Scholars Program of Shandong Province(tsqn201909065)Tsinghua University Initiative Scientific Research Program.
文摘With the ever-pressing issues of global energy demand and environmental pollution,molecular hydrogen has been receiving increasing attention as a clean alternative energy carrier.For hydrogen production,the design and development of high-performance catalysts remains rather challenging.As the compositions and structures of catalyst interfaces have paramount influences on the catalytic performances,the central topic here has always been to design and engineer the interface structures via rational routes so as to boost the activities and stabilities of electrocatalysts on hydrogen evolution reaction(HER).Here in this review,we focus on the design and preparation of multi-scale catalysts specifically catering to HER applications.We start from the design and structure-activity relationship of catalytic nanostructures,summarize the research progresses related to HER nanocatalysts,and interpret their high activities from the atomistic perspective;then,we review the studies regarding the design,preparation,HER applications and structure-activity relationship of single-atom site catalysts(SASCs),and thereupon discuss the future directions in designing HER-oriented SASCs.At the end of this review,we present an outlook on the development trends and faced challenges of catalysts for electrochemical HER.
基金This work was supported by The National Key Basic Research and Development(973)Program of China(2013CB932604 and 2012CB933403)The National Natural Science Foundation of China(Nos.51472117,11072109,11472131)+3 种基金the Research Fund of State Key Laboratory of Mechanics and Control of Mechanical Structures(0414K01,0413G01,0413Y02)the Jiangsu NSF(BK20131356,BK20130781)the Fundamental Research Funds for the Central Universities of China(No.NE2012005)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘When material dimensions are reduced to the nanoscale,exceptional physical mechanics properties can be obtained that differ significantly from the corresponding bulk materials.Here we review the physical mechanics of the friction of low‐dimensional nanomaterials,including zero‐dimensional nanoparticles,one‐dimensional multiwalled nanotubes and nanowires,and two‐dimensional nanomaterials-such as graphene,hexagonal boron nitride(h‐BN),and transition‐metal dichalcogenides-as well as topological insulators.Nanoparticles between solid surfaces can serve as rolling and sliding lubrication,while the interlayer friction of multiwalled nanotubes can be ultralow or significantly high and sensitive to interwall spacing and chirality matching,as well as the tube materials.The interwall friction can be several orders of magnitude higher in binary polarized h‐BN tubes than in carbon nanotubes mainly because of wall buckling.Furthermore,current extensive studies on two‐dimensional nanomaterials are comprehensively reviewed herein.In contrast to their bulk materials that serve as traditional dry lubricants(e.g.,graphite,bulk h‐BN,and MoS_(2)),large‐area high‐quality monolayered two‐dimensional nanomaterials can serve as single‐atom‐thick coatings that minimize friction and wear.In addition,by appropriately tuning the surface properties,these materials have shown great promise for creating energy‐efficient self‐powered electro‐opto‐magneto‐mechanical nanosystems.State‐of‐the‐art experimental and theoretical methods to characterize friction in nanomaterials are also introduced.
基金supported by the National Key Research and Development Program of China (2016YFD0100500 and 2016YFD0101703)the National Natural Science Foundation of China (Nos. 31601759 and 31471881)+1 种基金the Ministry of Agriculture of China (2016ZX08009-003-001)the Tai-Shan Scholar Program from the Shandong Provincial Government
文摘Tomato (Solanum lycopersicum) is the leading vegetable crop worldwide and an essential component of a healthy diet (Lin et al., 2014; Du et al., 2017). Fruit color is regarded as one of the most important commercial traits in tomato (The Tomato Genome Consortium, 2012). Consumers in different regions have different color preferences. For example, European and American consumers prefer red tomatoes, while pink tomatoes are more pop- ular in Asia countries, particularly in China and Japan (Ballester et al., 2010; Lin et al., 2014). However, most of tomato breeding ma- terials are red-fruited, thus the generation of pink-fruited materials is very important for Asian tomato production. Metabolomics and genetics studies demonstrate that the pink trait results from the absence of yellow-colored flavonoid naringenin chalcone (NarCh) in the peels,
基金This work was supported by the National Key Research and Development Program of China (2016YFD0101704), National Science Foundation of China (31470105), and Huazhong Agriculturat University startup fund (2013RC001).
文摘Dear Editor Pepper belongs to the Solanaceae family, which includes many important vegetable crops such as tomato, potato, and eggplant. Not only widely used as vegetables and spicy ingredients, pepper also has diverse applications in pharmaceutics, natural coloring agents, cosmetics, defense repellents, and as ornamental plants (Kim et al., 2014; Qin et al., 2014). Pepper is among the most widely cultivated and consumed vegetables in the world, with annual production reachincl to 38 million tons in 2011 (www.fao.
基金supported by The Strategic Priority Research Program of the Chinese Academy of Sciences (XDA01030505)Jiangsu Provincial Key Medical Center (YXZXB2016004)+3 种基金Key Research and Development Program of Jiangsu Province (BE2016612)National Natural Science Foundation of China (81771526)Excellent Youth Natural Science Foundation of Jiangsu Province (BK20170051)Six Talent Peaks Projects in Jiangsu Province (WSW-074)
文摘Intrauterine adhesion(IUA) is a common cause of uterine infertility and one of the most severe clinical features is endometrial fibrosis namely endometrial scarring for which there are few cures currently. Blocked angiogenesis is the main pathological change in the scarred endometrium. The fibroblast growth factor 2(b FGF), a member of FGF family, is usually applied to promote healing of refractory ulcer and contributes to angiogenesis of tissues. In this study, the sustained-release system of b FGF100 μg was administrated around scarred endometrium guiding by ultrasound every 4 weeks in 18 patients(2–4 times). Results showed that after treatment, the menstrual blood volume, endometrial thickness and the scarred endometrial area were improved.Histological study showed blood vessel density increased obviously. Three patients(3/18) achieved pregnancy over 20 gestational weeks. Therefore, administrating the b FGF surrounding scarred endometrium may provide a new therapeutic approach for the patients with endometrial fibrosis.
文摘Nickel-rich cathode materials have attracted considerable interest because of their high specific capacities,voltage ranges,and low cost.However,serious capacity attenuation and poor rate performance limit their application.This study proposes a novel strategy to improve the cycle stability of the nickel-rich LiNi0.sCo0.1Mn0.1O2(NCM811)layer material by designing core-shell LiNio.sCoo.1 Mno.102(CS-NCM811).CS-NCM811 is designed by the characteristic reaction between dimethylglyoxime(C4H8N2O2)and nickel ion to form Ni(C4H7N2O2)2-The CS-NCM811 is characterized with high nickel content in its core and high manganese content on its surface,leading to a high capacity and excellent cycle stability.The capacity retention of CS-NCM811 was 72.8%,much higher than that of NCM811(47.1%)after 500 cycles at a rate of 5 C.Not only is this method a no vel strategy to desig n high capacity cathode materials but also provides some new in sights into the cycle stability of nickel-rich layered cathode materials.
基金supported by the National Natural Science Foundation of China (Nos. 51074163 and 50834005)the Ministry of Education Support Program for New Century Excellent of China(No. NCET-08-0837)the Fundamental Research Funds for the Central Universities of China
文摘We analyzed the deformation characteristics of overlying stratum in backfilling with fully-mechanized and retaining roadways along the gob area coal mining technology, and established a mechanical model for the roof key stratum of retaining roadways along gob under the conditions of backfilling and fully- mechanized coal mining technology. Using Winkler elastic foundation theory, we analyzed a part of the key stratum under the action of elastic foundation coupling problem, and derived deflection analyt- ical expressions. Combined with specific conditions, we obtained the deflection curves for the roof key stratum of retaining roadways along gob under the conditions of backfilling and fully-mechanized coal mining technology. On this basis, we adopted the Coulomb's earth pressure theory to solve the problem of lateral pressure of the gangue filling area on the supporting wall beside the roadway and to provide the theoretical basis for reasonable selection of the distance between gangue concrete wall and roof and fur- ther discussion on the supporting stability of roadway.
基金supported by the National Natural Science Foundation of China(Grant No.31171176)Research Fund for the Doctoral Program of Higher Education of China(Grant No.755228001)+1 种基金Natural Science Foundation of Hunan Province(Grant No.11JJA002)the National Key Laboratory of Plant Molecular Genetics(Grant No.Y109Z711T1)
文摘The expression of FOAl (F-box overexpressed/oppressed ABA signaling) in different organs of Arabidopsis, and in response to ABA and NaCI, was analyzed. The expression level of FOAl is higher in the root and is lower in the stem, and is induced rapidly by ABA and NaC1. The phenotypes of T-DNA insertion mutant foal and FOAl overexpression lines FOAloxl and FOAlox2 were analyzed. The foal mutant exhibited a lower germination rate, shorter root length, more stomatal opening, in- creased proline accumulation and hypersensitivity to ABA compared with the wild type. In contrast, the overexpression lines showed lower sensitivity to ABA than the wild type. The expression levels of several ABA and stress-responsive transcription factors and genes were altered in the foal mutant in response to ABA. Compared with the wild type, the expression levels of ABA-responsive transcription factors were higher, but ABA and stress-responsive genes were lower in foal mutant. This study demonstrates that FOAl is an ABA signaling-related gene, and may play a negative role in ABA signaling.
基金supported by the Youth Innovation Promotion Association,Chinese Academy of Sciences(CAS)under grant no.2011152Shenyang National Laboratory for Materials Science,Institute of Metal Research,CAS,under grant no.2017RP06
文摘Flexible supercapacitors are promising energy storage devices in wearable smart electronics. Exploring cost-efficient electrodes with high capacitance would promote the wide-scale application of such capacitors. Herein, in order to explore a methodology for preparing low cost, flexible, tough, and up-scalable supercapacitor electrodes, silk textile is directly carbonized to make a conductive free-standing textile substrate. Through mildly baking the surfactant-free TiCTflakes suspension loaded on the carbonized silk cloth, a uniform and adhesive coating consisting of nanometer-thick TiCTflakes is well established on the conductive fabric support, forming a MXene-coated flexible textile electrode. The fabricated electrode exhibits a high areal capacitance of 362 m F/cm~2 with excellent cyclability and flexibility. Moreover,capacitance changes neglegibly under the bending deformation mode. This study elucidates the feasibility of using silk-derived carbon cloth from biomss for MXene-based flexible supercapacitor.
基金This work was supported by grants from the National Science Foundation of China(grant number 31770307)the Fundamental Research Funds for the Central Universities(grant reference Izujbky-2017-kb05).
文摘Pollen tube growth is crucial for successful fertilization.In Arabidopsis thaliana,the ANXUR(ANX)/BUPS receptor kinase complex controls and maintains pollen tube growth in response to autocrine rapid alkalin-ization factor 4/19(RALF4/19)signaling;however,the molecular and cellular mechanisms underlying the ANX/BUPS-mediated regulation of pollen tube growth remain unclear.In this study,we found that pollen-specific LORELEI-like GPI-anchored proteins 2 and 3(LLG2/3)promote pollen tube growth in vitro and in vivo.LLG2/3 interacte with ANX/BUPS in a RALF4-concentration-dependent manner,suggesting that ANX/BUPS and LLG2/3 might form a receptor-coreceptor complex for perceiving RALF peptide signals.Disruption of the ANX/BUPS-LLG2/3 interaction led to the cytoplasmic retention of ANX1/2,in either llg2/3 knockdown mutants or in anx1/2 mutants lacking the J region,which mediates the ANX/BUPS-LLG2/3 interaction.Moreover,we found that RALF4 induced the production of reactive oxygen species(ROS),which stimulate pollen tube growth and reduce pollen burst rate.ROS levels are reduced in the pollen tubes of LLG2/3 RNAi lines,and application of exogenous H2O2 could partially rescue the defective pollen tube growth of LLG2/3 RNAi lines.Taken together,our study identifies LLG2/3 as novel regulatory components of pollen tube growth,and shows that they chaperone ANX/BUPS for secretion to the apical plasma membrane of pollen tube and act as coreceptors of ANX/BUPS in the acti-vation of ROS production for promoting pollen tube growth.
文摘To the Editor:In sepsis,bacterial endotoxins play a central role by inducing a dysregulated and exaggerated release of inflammatory mediators and cytokines,often described as the“cytokine storm”or“cytokinemia.”[1]Both endotoxins and cytokines have been implicated in the development of organ dysfunction,including acute kidney injury(AKI).[2]Removing circulating endotoxins and excess cytokines from the circulation restores chemotactic gradients,localizing the immune response to the principal site of infection and re-establishing a regulated immune response.[1,3]Therefore,using hemofilters with enhanced endotoxin and cytokine adsorptive properties may bring about additional therapeutic benefits compared with conventional continuous renal replacement therapy(CRRT)filters.
基金supported by the National Natural Science Foundation of China(No.41001344)the China Postdoctoral Science Foundation Funded Project(2013M541696)+5 种基金the Jiangsu Planned Projects for Postdoctoral Research Funds(No.1301040C)the Program of Natural Science Research of Jiangsu Higher Education Institutions of China(No.13KJB610008)the Program of State Key Laboratory of Environmental Criteria and Risk Assessment,Chinese Research Academy of Environmental Sciences(No.SKLECRA2013OFP07)the Scientific Research Foundation of the High-level Personnel of Nanjing Normal University(No.2012105XGQ0102)the Program of Graduate Education Reform and Practice of Nanjing Normal University(No.1812000002A521)the Priority Academic Program Development of Jiangsu Higher Education Institutions(No.164320H116)
文摘This paper focused on the pollution characteristics, sources and lung cancer risk of atmospheric polycyclic aromatic hydrocarbons (PAHs) in a new urban district of Nanjing, China. Gaseous and aerosol PM2.5 (particulate matter with aerodynamic diameter smaller than 2.S μm) samples were collected in spring of 2015. Sixteen PAHs were extracted and analyzed after sampling. Firstly, arithmetic mean concentrations of PAHs and BaPeq (benzo[a]pyrene equivalent) were calculated. The mean concentrations of PAHs were 29.26 ± 14.13,18.14 ± 5.37 and 48.47 ± 16.03 ng/m3 in gas phase, particle phase and both phases, respectively. The mean concentrations of BaPeq were 0.87 ± 0.51, 2.71 ± 2.17 and 4.06 ± 2.31 ng/m3 in gas phase, particle phase and both phases, respectively. Secondly, diagnostic ratios and principal component analysis were adopted to identify the sources of PAHs and the outcomes were the same: traffic exhaust was the predominant source followed by fuel combustion and industrial process. Finally, incremental lung cancer risk (ILCR) induced by whole year inhalation exposure to PAHs for population groups of different age and gender were estimated based on a Monte Carlo simulation. ILCR values caused by particle phase PAHs were greater than those caused by gas phase PAHs. ILCR values for adults were greater than those for other age groups. ILCR values caused by total (gas + particle) PAHs for diverse groups were all greater than the significant level (10-6), indicating high potential lung cancer risk. Sensitivity analysis results showed that cancer slope factor for BaP inhalation exposure and BaPeq concentration had greater impact than body weight and inhalation rate on the ILCR.
基金Sanming Project of Medicine in Shenzhen(SZSM201612031)the National Natural Science Foundation of China(81722024,81772736,81571728)+3 种基金Chinese Academy of Sciences(YJKYYQ20180048)the Basic Research Foundation for Shenzhen’s Science and Technology(20190726095103499)the National Key Research and Development Program of China(2017YFA0205501,2017YFA0205503)the Youth Innovation Promotion Association(2014078).
文摘Ferritin,an iron-storage protein,regulates cellular iron metabolism and oxidative stress.The ferritin structure is characterized as a spherical cage,inside which large amounts of iron are deposited in a safe,compact and bioavailable form.All ferritins readily catalyze Fe(II)oxidation by peroxides at the ferroxidase center to prevent free Fe(II)from participating in oxygen free radical formation via Fenton chemistry.Thus,ferritin is generally recognized as a cytoprotective stratagem against intracellular oxidative damage.The expression of cytosolic ferritins is usually regulated by iron status and oxidative stress at both the transcriptional and post-transcriptional levels.The mechanism of ferritin-mediated iron recycling is far from clarified,though nuclear receptor co-activator 4(NCOA4)was recently identified as a cargo receptor for ferritin-based lysosomal degradation.Cytosolic ferritins are heteropolymers assembled by H-and L-chains in different proportions.The mitochondrial ferritins are homopolymers and distributed in restricted tissues.They play protective roles in mitochondria where heme-and Fe/S-enzymes are synthesized and high levels of ROS are produced.Genetic ferritin disorders are mainly related to the L-chain mutations,which generally cause severe movement diseases.This review is focused on the biochemistry and function of mammalian intracellular ferritin as the major iron-storage and anti-oxidation protein.
基金financially supported by the National Natural Science Foundation of China(51802077,21975129)the Fundamental Research Funds for the Central Universities(2019B16214)+1 种基金China Postdoctoral Science Foundation(2016 T90414)Jiangsu Planned Projects for Postdoctoral Research Funds(1601026A)。
文摘Although one-dimensional Pt nanocrystals have long been regarded as ideal electrode catalysts for fuel cells,the synthetic techniques commonly involve the use of various complicated templates or surfactants,which have largely hampered their large-scale industrial application.Herein,we present a convenient and cost-effective approach to the stereoassembly of quasi-one-dimensional grain boundary-enriched Pt nanoworms on nitrogen-doped low-defect graphitic carbon nanosheets(Pt NWs/NL-CNS).Benefiting from its numerous catalytically active grain boundaries as well as optimized electronic structure,the as-derived Pt NWs/NL-CNS catalyst possesses exceptionally good electrocatalytic properties for methanol oxidation,including an ultrahigh mass activity of 1949.5 mA mg^(-1), reliable long-term durability,and strong poison tolerance,affording one of the most active Pt-based electrocatalysts for methanol oxidation reaction.Density functional theory calculation further reveals that the formation of worm-shape Pt morphology is attributed to the modified electronic structure as well as controllable defect density of the carbon matrix,which could also weaken the adsorption ability of Pt towards CO molecule and meanwhile synergistically promotes the catalytic reaction kinetics.
基金This work was supported by China Postdoctoral Science Foundation(Nos.2019T120754 and 2018M633229)Sanming Project of Medicine in Shenzhen(No.SZSM201612031)+4 种基金Natural Science Foundation of Guangdong Province of China(Nos.2018A030310665 and 2018A0303130295)Shenzhen Science and Technology Innovation Committee(Nos.ZDSYS201707281114196,JCYJ20170306091657539,JCYJ20170413162242627,JCYJ20190806163814395,JCYJ-20170306091452714,and GJHZ20170313172439851)Development and Reform Commission of Shenzhen Municipality(No.S2016005470013)National Key R&D Program of China(No.2017YFA0205501)the National Natural Science Foundation of China(Nos.81722024 and 81571728).
文摘Nanozymes are nanomaterials with enzyme-like properties that have attracted significant interest owing to their capability to address the limitations of traditional enzymes such as fragility,high cost,and impossible mass production.Over the past decade,a broad variety of nanomaterials have been found to mimic the enzyme-like activity by engineering the active centers of natural enzymes or developing multivalent elements within nanostructures.Carbon nanomaterials with well-defined electronic and geometric structures have served as favorable surrogates of traditional enzymes by mimicking the highly evolved catalytic center of natural enzymes.In particular,by combining the unique electronic,optical,thermal,and mechanical properties,carbon nanomaterials-based nanozymes can offer a variety of multifunctional platforms for biomedical applications.In this review,we will introduce the enzymatic characteristics and recent advances of carbon nanozymes,and summarize their significant applications in biomedicine.
基金support from the National Natural Science Foundation of China(No.82072324)the National Key R&D Program of China(No.2019YFA0709200)+1 种基金National Natural Science Foundation of China Foundation of Innovative Research Group grant(No.22121003)the Chongqing Special Key Project of Technological Innovation and Application Development(No.cstc2019jscx-gksbX0053).
文摘During criminal case investigations,blood evidence tracing is critical for criminal investigation.However,the blood stains are often cleaned or covered up after the crime,resulting in trace residue and difficult tracking.Therefore,a highly sensitive and specific method for the rapid detection of human blood stains remains urgent.To solve this problem,we established a nanozyme-based strip for rapid detection of blood evidence with high sensitivity and specificity.To construct reliable nanozyme strips,we synthesized CoFe_(2)O_(4) nanozymes with high peroxidase-like activity by scaling up to gram level,which can be supplied for six million tests,and conjugated antibody as a detection probe in nanozyme strip.The developed CoFe_(2)O_(4) nanozyme strip can detect human hemoglobin(HGB)at a concentration as low as 1 ng/mL,which is 100 times lower than the commercially available colloidal gold strips(100 ng/mL).Moreover,this CoFe_(2)O_(4) nanozyme strip showed high generality on 12 substrates and high specificity to human HGB among 13 animal blood samples.Finally,we applied the developed CoFe_(2)O_(4) nanozyme strip to successfully detect blood stains in three real cases,where the current commercial colloidal gold strip failed to do.The results suggest that the CoFe_(2)O_(4) nanozyme strip can be used as an effective on-scene detection method for human blood stains,and can further be used as a long-term preserved material evidence for traceability inquiry.
基金supported by the National Natural Science Foundation of China(31470376)the"Qilu Scholarship"from Shandong University(11200083963009)"1000-talents Plan"from China for young researchers(11200084963002)
文摘Plant receptor-like protein kinases(RLKs) are transmembrane proteins with an extracellular domain and an intracellular kinase domain, which enable plant perceiving diverse extracellular stimuli to trigger the intracellular signal transduction. The somatic embryogenesis receptor kinases(SERKs) code the leucine-rich-repeat receptor-like kinase(LRR-RLK), and have been demonstrated to associate with multiple ligand-binding receptors to regulate plant growth, root development, male fertility, stomatal development and movement, and immune responses. Here, we focus on the progress made in recent years in understanding the versatile functions of Arabidopsis SERK proteins, and review SERK proteins as co-receptor to perceive different endogenous and environmental cues in different signaling pathway, and discuss how the kinase activity of SERKs is regulated by various modification.
基金supported by the National Natural Science Foundation of China(81270897,81300668,81370939,81400813,81400808,81530026,81370922)the Jiangsu Provincial Special Program of Medical Science(BL2012026)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions support this study
文摘Type 1 diabetes mellitus is heterogeneous in many facets. The patients suffered from type 1 diabetes present several levels of islet function as well as variable number and type of islet-specific autoantibodies. This study was to investigate prevalence and heterogeneity of the islet autoantibodies and clinical phenotypes of type 1 diabetes mellitus; and also discussed the process of islet failure and its risk factors in Chinese type 1 diabetic patients. A total of 1,291 type 1 diabetic patients were enrolled in this study. Demographic information was collected. Laboratory tests including mixed-meal tolerance test, human leukocyte antigen alleles, hemoglobin A1 c, lipids, thyroid function and islet autoantibodies were conducted. The frequency of islet-specific autoantibody in newly diagnosed T1 DM patients(duration shorter than half year) was 73% in East China. According to binary logistic regressions, autoantibody positivity, longer duration and lower Body Mass Index were the risk factors of islet failure. As the disease developed, autoantibodies against glutamic acid decarboxylase declined as well as the other two autoantibodies against zinc transporter 8 and islet antigen 2. The decrease of autoantibodies was positively correlated with aggressive beta cell destruction. Autoantibodies can facilitate the identification of classic T1 DM from other subtypes and predict the progression of islet failure. As there were obvious heterogeneity in autoantibodies and clinical manifestation in different phenotypes of the disease, we should take more factors into consideration when identifying type 1 diabetes mellitus.