β-Sitosterol is a type of phytosterol that occurs naturally in plants.Previous studies have shown that it has anti-oxidant,anti-hyperlipidemic,anti-inflammatory,immunomodulatory,and anti-tumor effects,but it is unkno...β-Sitosterol is a type of phytosterol that occurs naturally in plants.Previous studies have shown that it has anti-oxidant,anti-hyperlipidemic,anti-inflammatory,immunomodulatory,and anti-tumor effects,but it is unknown whetherβ-sitosterol treatment reduces the effects of ischemic stroke.Here we found that,in a mouse model of ischemic stroke induced by middle cerebral artery occlusion,β-sitosterol reduced the volume of cerebral infarction and brain edema,reduced neuronal apoptosis in brain tissue,and alleviated neurological dysfunction;moreover,β-sitosterol increased the activity of oxygen-and glucose-deprived cerebral cortex neurons and reduced apoptosis.Further investigation showed that the neuroprotective effects ofβ-sitosterol may be related to inhibition of endoplasmic reticulum stress caused by intracellular cholesterol accumulation after ischemic stroke.In addition,β-sitosterol showed high affinity for NPC1L1,a key transporter of cholesterol,and antagonized its activity.In conclusion,β-sitosterol may help treat ischemic stroke by inhibiting neuronal intracellular cholesterol overload/endoplasmic reticulum stress/apoptosis signaling pathways.展开更多
In this study,a human-sensitive frequency band vibration isolator(HFBVI)with quasi-zero stiffness(QZS)characteristics for heavy-duty truck seats is designed to improve the comfort of heavy-duty truck drivers on uneven...In this study,a human-sensitive frequency band vibration isolator(HFBVI)with quasi-zero stiffness(QZS)characteristics for heavy-duty truck seats is designed to improve the comfort of heavy-duty truck drivers on uneven roads.First,the analytical expressions for the force and displacement of the HFBVI are derived with the Lagrange equation and d'Alembert's principle,and are validated through the prototype restoring force testing.Second,the harmonic balance method(HBM)is used to obtain the dynamic responses under harmonic excitation,and further the influence of pre-stretching on the dynamic characteristics and transmissibility is discussed.Finally,the experimental prototype of the HFBVI is fabricated,and vibration experiments are conducted under harmonic excitation to verify the vibration isolation performance(VIP)of the proposed vibration isolator.The experimental results indicate that the HFBVI can effectively suppress the frequency band(4-8 Hz)to which the human body is sensitive to vertical vibration.In addition,under real random road spectrum excitation,the HFBVI can achieve low-frequency vibration isolation close to 2 Hz,providing new prospects for ensuring the health of heavy-duty truck drivers.展开更多
"Synthetic"allopolyploids recreated by interspecific hybridization play an important role in providing novel genomic variation for crop improvement.Such synthetic allopolyploids often undergo rapid genomic s..."Synthetic"allopolyploids recreated by interspecific hybridization play an important role in providing novel genomic variation for crop improvement.Such synthetic allopolyploids often undergo rapid genomic structural variation(SV).However,how such SV arises,is inherited and fixed,and how it affects important traits,has rarely been comprehensively and quantitively studied in advanced generation synthetic lines.A better understanding of these processes will aid breeders in knowing how to best utilize synthetic allopolyploids in breeding programs.Here,we analyzed three genetic mapping populations(735 DH lines)derived from crosses between advanced synthetic and conventional Brassica napus(rapeseed)lines,using whole-genome sequencing to determine genome composition.We observed high tolerance of large structural variants,particularly toward the telomeres,and preferential selection for balanced homoeologous exchanges(duplication/deletion events between the A and C genomes resulting in retention of gene/chromosome dosage between homoeologous chromosome pairs),including stable events involving whole chromosomes("pseudoeuploidy").Given the experimental design(all three populations shared a common parent),we were able to observe that parental SV was regularly inherited,showed genetic hitchhiking effects on segregation,and was one of the major factors inducing adjacent novel and larger SV.Surprisingly,novel SV occurred at low frequencies with no significant impacts on observed fertility and yield-related traits in the advanced generation synthetic lines.However,incorporating genome-wide SV in linkage mapping explained significantly more genetic variance for traits.Our results provide a framework for detecting and understanding the occurrence and inheritance of genomic SV in breeding programs,and support the use of synthetic parents as an important source of novel trait variation.展开更多
For improving the actuation performance at low electric fields of dielectric elastomers,achieving high dielectric constant(εr)and low modulus(Y)simultaneously has been targeted in the past decades,but there are few w...For improving the actuation performance at low electric fields of dielectric elastomers,achieving high dielectric constant(εr)and low modulus(Y)simultaneously has been targeted in the past decades,but there are few ways to accomplish both.In contrast to the classical strategies such as incorporating plasticizers or ceramic to prepare the silicon-based dielectric elastomers,here,blending an amino-complexed hybrid(polyethyleneimine(PEI)-Ag)with polydimethylsiloxane(PDMS)elastomer is reported as an alternative strategy to tailor theεr and Y.PEI-Ag not only exhibits excellent dielectric enhancement properties but also minimizes the PDMS crosslinking through amino-complexed reaction between PEI and Pt catalysts.The prepared dielectric elastomers have aεr of 7.2@10^(3)Hz and Y of 1.14 MPa,leading to an actuation strain of 22.27%at 35 V/μm.Hence,incorporating such novel hybrids based on dual amino-complexed effect on both matrix and particles sufficiently promotes the actuated performance of dielectric elastomers.展开更多
High-energy lithium-sulfur batteries(LSBs)have experienced relentless development over the past decade with discernible improvements in electrochemical performance.However,a scrutinization of the cell operation condit...High-energy lithium-sulfur batteries(LSBs)have experienced relentless development over the past decade with discernible improvements in electrochemical performance.However,a scrutinization of the cell operation conditions reveals a huge gap between the demands for practical batteries and those in the literature.Low sulfur loading,a high electrolyte/sulfur(E/S)ratio and excess anodes for lab-scale LSBs significantly offset their high-energy merit.To approach practical LSBs,high loading and lean electrolyte parameters are needed,which involve budding challenges of slow charge transfer,polysulfide precipitation and severe shuttle effects.To track these obstacles,the exploration of electrocatalysts to immobilize polysulfides and accelerate Li-S redox kinetics has been widely reported.Herein,this review aims to survey state-of-the-art catalytic materials for practical LSBs with emphasis on elucidating the correlation among catalyst design strategies,material structures and electrochemical performance.We also statistically evaluate the state-of-the-art catalyst-modified LSBs to identify the remaining discrepancy between the current advancements and the real-world requirements.In closing,we put forward our proposal for a catalytic material study to help realize practical LSBs.展开更多
American lotus(Nelumbo lutea)is one of the two species in Nelumbo and has only yellow flower.Identification of total flavonoids showed wild American lotus contained almost only flavonols with quercetin 3-O-glucuronide...American lotus(Nelumbo lutea)is one of the two species in Nelumbo and has only yellow flower.Identification of total flavonoids showed wild American lotus contained almost only flavonols with quercetin 3-O-glucuronide to be the dominant pigment.The variation tendency of the total flavonol content was coincident with yellow color variation of petals during flower development.To understand the mechanism of accumulation and constituent of pigments in petals,three pivotal genes,NlFLS1,NlFLS2 and NlFLS3,which were predicted to encode flavonol synthases were isolated and characterized by analyses of basic bioinformatics,temporal and spatial expression patterns and enzymatic activity.Their temporal expression levels showed the same variation tendency,which was also consistent with the development-dependent variation of total flavonol content.Spatial expression patterns indicated the three genes should function in petals.All the three proteins were demonstrated to be bifunctional dioxygenase,possessing both flavonol synthase activity and flavanone 3-hydroxylase activity.Besides,other flavonol biosynthesis related genes were also investigated on their expression levels to give more clues on the mechanism.Substrate preferences of the three FLSs,substrate competitions between the FLSs and other flavonol biosynthesis related enzymes,and the greatly differential expression levels between F3’H(flavonoid 3-hydroxylase)and F3’5’H(flavonoid 3,5-hydroxylase)contributed to the flavonol constituent in the petals of America lotus,namely abundant quercetin-derivatives while very few kaempferol-derivatives and myricetin-derivatives.展开更多
Diabetes mellitus, a type of chronic metabolic disease, is occurring more frequently and causes severe threats to human health. In vivo, exercise can stimulate skeletal muscle cells to secrete and release myokines int...Diabetes mellitus, a type of chronic metabolic disease, is occurring more frequently and causes severe threats to human health. In vivo, exercise can stimulate skeletal muscle cells to secrete and release myokines into blood circulation, which will participate in metabolism and act on multiple organs or systems. Recently, the relationship between myokines and diabetes mellitus was a hot research topic, and myokines may be potential targets for the diagnosis, monitoring, prevention and treatment of diabetes mellitus. In this review, we elucidated the multiple effects of common myokines in the pathogenesis and therapy of diabetes mellitus, which will provide a theoretical foundation of the mechanism in the positive effects of exercises on humans.展开更多
Begonia, one of the most diverse plant taxa and the fifth or sixth largest angiosperm genus, consists of over1800 accepted species. The number of species recognized within this genus has greatly increased over the pas...Begonia, one of the most diverse plant taxa and the fifth or sixth largest angiosperm genus, consists of over1800 accepted species. The number of species recognized within this genus has greatly increased over the past 20 years, rising from 80 to 200 species in China alone. Based on recent field surveys, the number of begonia species in China is predicted to be between 250 and 300. Given the large number of begonia species that still remain to be described, further taxonomical work is urgently required. This is especially true for Chinese Begonia, in which there is a huge diversity of habitat, habit, plant size, leaf type, flower and fruit morphology, and most species are narrowly distributed in isolated habitats that are subject to negative disturbances from climate change, as well as agricultural and industrial activities. Although the conservation status for the majority of species has been evaluated using the standards of the International Union for Conservation of Nature, the results don't represent the truth in many species, and also about11.5% of which are data-absent. In addition, illegal collection and over-harvesting of wild begonias for ornamental or medicinal use has increased due to the rapid development of internet commerce. Far more often than predicted, these species should be categorized as rare and endangered and require immediate protection. Ex situ conservation of Chinese begonias started in 1995 and over 60% of the total species have been so far introduced into cultivation by several major botanical gardens in China. However, only few research institutions, limited funds and human resources have been involved in Begonia conservation;moreover, no project has conducted reintroduction. Therefore, more conservation-based work remains to be done. Improved conservation of Chinese begonias in the future depends on further field survey, an improved understanding of population diversity, and integrative approaches, including in situ and ex situ conservation, seed banking, and plant reintroduction. Species-targeted conservation zones should be established for endangered species excluded from the existing nature reserves. Additionally, laws pertaining to plant protection should be extended to prevent the illegal collection and transaction of wild plants, particularly for those species with unique habitats and small populations.展开更多
Previous study have demonstrated that a compound composed of water-soluable Ganoderma lucidum polysaccharides(GLP)and Polyporus umbellatus polysaccharides(PUP)in a ratio of 3:1 named GPP enhances innate immune functio...Previous study have demonstrated that a compound composed of water-soluable Ganoderma lucidum polysaccharides(GLP)and Polyporus umbellatus polysaccharides(PUP)in a ratio of 3:1 named GPP enhances innate immune function in mice through enhancing the function of macrophage cells and activity of natural killer(NK)cells.Here in our research,we further investigated the effect of GPP on the diversity and composition of intestinal flora,and explored its effect on colitis model mice.The immunoregulatory verification experiments of GPP were conducted in both normal and DSS-induced mice model.Our research showed that GPP increased the diversity of intestinal microorganisms in mice with the extension of administration time.Daily GPP intake attenuated DSS-induced colon injury,protected the splenic lymphocyte proliferation ability,enhanced the serum hemolysin synthesis,and increased peripheral phagocytes and NK cell activity in model mice.Comparisons of the predominant gene pathways of the bacterial microbiota showed that DNA repair and recombination,base mismatch repair pathways was stronger in GPP-treatment group than in control group,indicating the possible molecular mechanisms of immune function regulation.Our study showed that GPP regulated immune function in both health and colitis model,and had a positive effect on maintaining intestinal flora homeostasis.展开更多
Aurelia spp.ephyrae have been reported to form blooms in sea cucumber aquaculture ponds in the Bohai and Yellow Seas.To identify the species,we carried out a genetic analysis of Aurelia spp.ephyrae and medusae based o...Aurelia spp.ephyrae have been reported to form blooms in sea cucumber aquaculture ponds in the Bohai and Yellow Seas.To identify the species,we carried out a genetic analysis of Aurelia spp.ephyrae and medusae based on mitochondrial 16 S rRNA gene.Samples offour Aurelia sp.ephyrae populations were collected in sea cucumber aquaculture ponds and samples offour Aurelia sp.medusae populations were collected in coastal waters.Using a BLASTn search,we found that both the ephyrae collected in the aquaculture ponds and medusae collected in coastal waters belong to Aurelia coerulea.Seventeen haplotypes were recovered from the 16 S rRNA gene.The overall haplotype diversity and nucleotide diversity of the 166 A.coerulea individuals were 0.686%and 0.329%,respectively,indicating high haplotype diversity and low nucleotide diversity.Moreover,the haplotype diversity of ephyrae populations were generally lower than that of medusae populations with close sampling points.The genetic differentiation between ephyrae populations collected in the sea cucumber aquaculture ponds and A.coerulea medusae collected in coastal waters was not significant,suggesting the ephyrae populations in the sea cucumber culture ponds were part of the same genetic group as the medusae populations in the coastal waters.Phylogeographic analysis of the 16 S rRNA region revealed that there was no significant correlation between the haplotypes and the geographic distribution of populations.Pairwise fixation index values showed significant genetic differentiation and limited gene flow between A.coerulea population of Weifang and other locations.展开更多
Objective:Previous studies have found that Qidi Tangshen granules(QDTS),a combination therapy of supplementing essence(Tianjing,TJ)and unblocking the collaterals(Tongluo,TL),can reduce kidney damage in db/db mice.This...Objective:Previous studies have found that Qidi Tangshen granules(QDTS),a combination therapy of supplementing essence(Tianjing,TJ)and unblocking the collaterals(Tongluo,TL),can reduce kidney damage in db/db mice.This study aimed to explore the effect of QDTS and their separate prescriptions on podocytes in mice with diabetic nephropathy.Methods:The db/db mice were used in this experiment as an animal model,while wild-type C57BL/6J mice were used as normal controls.At the age of 12 weeks,the db/db mice were randomly divided into 5 groups(db/db,db/dbþvalsartan,db/dbþQDTS,db/dbþTJ and db/dbþTL).The urine albumin excretion ratio(UAE)was measured by enzyme-linked immunosorbent assay before and after the intervention.The ultrastructure of the kidney podocytes was observed by transmission electron microscopy.The protein expression levels of nephrin and desmin were detected by immunohistochemistry.Results:QDTS and their separate prescriptions significantly decreased the UAE and attenuated the renal pathological injury.QDTS and their separate prescriptions also reduced the fusion rate of the foot processes and increased the expression of nephrin protein.In contrast,QDTS and their separate prescriptions(TJ and TL)reduced the expression level of desmin protein.Conclusion:QDTS and their separate prescriptions might reduce diabetes-induced renal injury by reducing podocyte damage.The therapeutic effect of QDTS was more pronounced than TJ and TL.展开更多
The spreading of cancer cells from the primary tumor site to other parts of the body,known as metastasis,is the leading cause of cancer recurrence and mortality in patients with triple-negative breast cancer(TNBC).Ove...The spreading of cancer cells from the primary tumor site to other parts of the body,known as metastasis,is the leading cause of cancer recurrence and mortality in patients with triple-negative breast cancer(TNBC).Overexpression of epidermal growth factor receptor(EGFR)is observed in approximately 70%of TNBC patients.EGFR is crucial for promoting tumor metastasis and associated with poor prognosis.Therefore,it is vital to identify effective therapeutic strategies targeting EGFR inhibition.Ononin,an isoflavonoid found in various plants,such as clover and soybeans,has been shown to have anticancer properties in several cancers.In the present study,we aimed to investigate the effects of ononin on TNBC lung metastasis and the associated molecular pathways.We used various assays,including cell viability,colony formation,Transwell,wound healing,ELISA,Western blotting,and staining techniques,to achieve this objective.The results demonstrated that ononin effectively suppressed cellular proliferation and induced apoptosis,as evidenced by the cell viability assay,colony formation assay,and expression of apoptosis markers,and reduced the metastatic capabilities of TNBC cells.These effects were achieved through the direct suppression of cell adhesion,invasiveness and motility.Furthermore,in TNBC xenograft lung metastatic models,ononin treatment significantly reduced tumor growth and lung metastasis.Additionally,ononin reversed the epithelial-mesenchymal transition(EMT)by downregulating the expression of EMT markers and matrix metalloproteinases,as confirmed by Western blot analysis.Furthermore,ononin treatment reduced EGFR phosphorylation and suppressed the PI3K,Akt,and m TOR signaling pathways,which was further confirmed using EGFR agonists or inhibitors.Importantly,ononin treatment did not exert any toxic effects on liver or kidney function.In conclusion,our findings suggest that ononin is a safe and potentially therapeutic treatment for TNBC metastasis that targets the EGFRmediated PI3K/Akt/m TOR pathway.Further studies are warranted to validate its efficacy and explore its potential clinical applications.展开更多
The binary polyhydrides of heavy rare earth lutetium that shares a similar valence electron configuration to lanthanum have been experimentally discovered to be superconductive.The lutetium polyhydrides were successfu...The binary polyhydrides of heavy rare earth lutetium that shares a similar valence electron configuration to lanthanum have been experimentally discovered to be superconductive.The lutetium polyhydrides were successfully synthesized at high pressure and high temperature conditions using a diamond anvil cell in combinations with the in-situ high pressure laser heating technique.The resistance measurements as a function of temperature were performed at the same pressure of synthesis in order to study the transitions of superconductivity(SC).The superconducting transition with a maximum onset temperature(Tc)71 K was observed at pressure of 218 GPa in the experiments.The Tcdecreased to 65 K when pressure was at 181 GPa.From the evolution of SC at applied magnetic fields,the upper critical field at zero temperatureμ0Hc2(0)was obtained to be~36 T.The in-situ high pressure X-ray diffraction experiments imply that the high TcSC should arise from the Lu4H23phase with Pm3n symmetry that forms a new type of hydrogen cage framework different from those reported for previous light rare earth polyhydride superconductors.展开更多
Interface regulation plays a key role in the electrochemical performance for biosensors.By controlling the interfacial interaction,the electronic structure of active species can be adjusted effectively at micro and na...Interface regulation plays a key role in the electrochemical performance for biosensors.By controlling the interfacial interaction,the electronic structure of active species can be adjusted effectively at micro and nano-level,which results in the optimal reaction energy barrier.Herein,we propose an interface electronic engineering scheme to design a strongly coupled 1T phase molybdenum sulfide(1T-MoS2)/MXene hybrids for constructing an efficient electrocatalytic biomimetic sensor.The local electronic and atomic structures of the 1T-MoS2/Ti3C2TX are comprehensively studied by synchrotron radiation-based X-ray photoelectron spectroscopy(XPS),as well as X-ray absorption spectroscopy(XAS)at atomic level.Experiments and theoretical calculations show that there are interfacial stresses,atomic defects and adjustable bond-length between MoS2/MXene nanosheets,which can significantly promote biomolecular adsorption and rapid electron transfer to achieve excellent electrochemical activity and reaction kinetics.The 1T-MoS2/Ti3C2TX modified electrode shows ultra high sensitivity of 1.198μA/μM for dopamine detection with low limit of 0.05μM.We anticipate that the interface electronic engineering investigation could provide a basic idea for guiding the exploration of advanced biosensors with high sensitivity and low detection limit.展开更多
Single-atom nanozymes(SAzymes)are emerging as promising alternatives to mimic natural enzyme,which is due to high atomic utilization efficiency,well-defined geometric,and unique electronic structure.Herein,Fe single a...Single-atom nanozymes(SAzymes)are emerging as promising alternatives to mimic natural enzyme,which is due to high atomic utilization efficiency,well-defined geometric,and unique electronic structure.Herein,Fe single atoms supported on Ti_(3)C_(2)T_(x)(Fe-SA/Ti_(3)C_(2)T_(x))with intrinsic peroxidase activity is developed,further constructing a sensitive Raman sensor array for sensing of five antioxidants.Fe-SA/Ti_(3)C_(2)T_(x)shows excellent peroxidase-like performance in catalyzing the oxidation of 3,3',5,5'-tetramethylbenzidine(TMB)with colorimetric reactions.X-ray adsorption fine structure(XAFS)reveals that the electron transport between the Ti_(3)C_(2)T_(x)and Fe atoms occurs along Fe-O-Ti ligands,meanwhile the density functional theory(DFT)calculations confirm the spontaneous dissociation of H_(2)O_(2)and the formation of OH radicals.Furthermore,the peroxidase-like Fe-SA/Ti_(3)C_(2)T_(x)was used as surface enhanced Raman scattering(SERS)substrate of oxidized TMB(TMB+)and achieved satisfied signal amplification performance.Using the blocking effects of free radical reactions,one-off identification of 5 antioxidants,including ascorbic acid(AA),uric acid(UA),glutathione(GSH),melatonin(Mel),and tea polyphenols(TPP),could be realized with this high identifiable catalytic property.This principle could realize 100%distinguish accuracy combined with linear discriminant analysis(LDA)and heat map data analysis.A wide detection concentration ranges from 10^(-8)to 10^(-3)M for five antioxidants was also achieved.展开更多
Owing to the unique coordination environment and high atom utilization efficiency,single atom catalysts have been considered as an ideal artificial enzyme to mimic natural enzymes.Herein,single-atom Fe nanozyme anchor...Owing to the unique coordination environment and high atom utilization efficiency,single atom catalysts have been considered as an ideal artificial enzyme to mimic natural enzymes.Herein,single-atom Fe nanozyme anchored on N-doped Ti_(3)C_(2)Tx(Fe SA/N-Ti_(3)C_(2)Tx)with asymmetrically coordinated Fe-N_(1)C_(2)configuration is synthesized by vacancy capture and heteroatom doping strategy,which exhibits excellent peroxidase-like activity.Based on the results of peroxidase catalytic kinetics and X-ray adsorption fine spectroscopy,the Fe-N_(1)C_(2)active sites in Fe SA/N-Ti_(3)C_(2)Tx are responsible for the excellent performance.Furthermore,the developed Fe SA/N-Ti_(3)C_(2)Tx can be employed to quantitative detection of melatonin(MT),which shows a wide linear detection range(0.01-100μM)and an excellent detection limit(7.3 nM)in buffer,0.01-100μM and 7.8 nM in serum samples.Our work proves that MXene-based single atoms can be promising nanozyme in the field of bioassays.展开更多
基金supported by the National Natural Science Foundation of China,Nos.82104158(to XT),31800887(to LY),31972902(to LY),82001422(to YL)China Postdoctoral Science Foundation,No.2020M683750(to LY)partially by Young Talent Fund of University Association for Science and Technology in Shaanxi Province of China,No.20200307(to LY).
文摘β-Sitosterol is a type of phytosterol that occurs naturally in plants.Previous studies have shown that it has anti-oxidant,anti-hyperlipidemic,anti-inflammatory,immunomodulatory,and anti-tumor effects,but it is unknown whetherβ-sitosterol treatment reduces the effects of ischemic stroke.Here we found that,in a mouse model of ischemic stroke induced by middle cerebral artery occlusion,β-sitosterol reduced the volume of cerebral infarction and brain edema,reduced neuronal apoptosis in brain tissue,and alleviated neurological dysfunction;moreover,β-sitosterol increased the activity of oxygen-and glucose-deprived cerebral cortex neurons and reduced apoptosis.Further investigation showed that the neuroprotective effects ofβ-sitosterol may be related to inhibition of endoplasmic reticulum stress caused by intracellular cholesterol accumulation after ischemic stroke.In addition,β-sitosterol showed high affinity for NPC1L1,a key transporter of cholesterol,and antagonized its activity.In conclusion,β-sitosterol may help treat ischemic stroke by inhibiting neuronal intracellular cholesterol overload/endoplasmic reticulum stress/apoptosis signaling pathways.
基金supported by the National Natural Science Foundation of China(No.12172226)。
文摘In this study,a human-sensitive frequency band vibration isolator(HFBVI)with quasi-zero stiffness(QZS)characteristics for heavy-duty truck seats is designed to improve the comfort of heavy-duty truck drivers on uneven roads.First,the analytical expressions for the force and displacement of the HFBVI are derived with the Lagrange equation and d'Alembert's principle,and are validated through the prototype restoring force testing.Second,the harmonic balance method(HBM)is used to obtain the dynamic responses under harmonic excitation,and further the influence of pre-stretching on the dynamic characteristics and transmissibility is discussed.Finally,the experimental prototype of the HFBVI is fabricated,and vibration experiments are conducted under harmonic excitation to verify the vibration isolation performance(VIP)of the proposed vibration isolator.The experimental results indicate that the HFBVI can effectively suppress the frequency band(4-8 Hz)to which the human body is sensitive to vertical vibration.In addition,under real random road spectrum excitation,the HFBVI can achieve low-frequency vibration isolation close to 2 Hz,providing new prospects for ensuring the health of heavy-duty truck drivers.
基金supported by the National Natural Science Foundation of China(NSFC,31970564,32000397,32171982)the Fundamental Research Funds for the Central Universities(2662023PY004)。
文摘"Synthetic"allopolyploids recreated by interspecific hybridization play an important role in providing novel genomic variation for crop improvement.Such synthetic allopolyploids often undergo rapid genomic structural variation(SV).However,how such SV arises,is inherited and fixed,and how it affects important traits,has rarely been comprehensively and quantitively studied in advanced generation synthetic lines.A better understanding of these processes will aid breeders in knowing how to best utilize synthetic allopolyploids in breeding programs.Here,we analyzed three genetic mapping populations(735 DH lines)derived from crosses between advanced synthetic and conventional Brassica napus(rapeseed)lines,using whole-genome sequencing to determine genome composition.We observed high tolerance of large structural variants,particularly toward the telomeres,and preferential selection for balanced homoeologous exchanges(duplication/deletion events between the A and C genomes resulting in retention of gene/chromosome dosage between homoeologous chromosome pairs),including stable events involving whole chromosomes("pseudoeuploidy").Given the experimental design(all three populations shared a common parent),we were able to observe that parental SV was regularly inherited,showed genetic hitchhiking effects on segregation,and was one of the major factors inducing adjacent novel and larger SV.Surprisingly,novel SV occurred at low frequencies with no significant impacts on observed fertility and yield-related traits in the advanced generation synthetic lines.However,incorporating genome-wide SV in linkage mapping explained significantly more genetic variance for traits.Our results provide a framework for detecting and understanding the occurrence and inheritance of genomic SV in breeding programs,and support the use of synthetic parents as an important source of novel trait variation.
基金supported by Sichuan Science and Technology Program(2022ZHCG0122)the NSAF project(U2230120)+1 种基金Youth Science and Technology Innovation Team of Sichuan Province of Functional Polymer Composites(2021JDTD0009)the Key Researched Development Program of Sichuan Province(2022YFG0271).
文摘For improving the actuation performance at low electric fields of dielectric elastomers,achieving high dielectric constant(εr)and low modulus(Y)simultaneously has been targeted in the past decades,but there are few ways to accomplish both.In contrast to the classical strategies such as incorporating plasticizers or ceramic to prepare the silicon-based dielectric elastomers,here,blending an amino-complexed hybrid(polyethyleneimine(PEI)-Ag)with polydimethylsiloxane(PDMS)elastomer is reported as an alternative strategy to tailor theεr and Y.PEI-Ag not only exhibits excellent dielectric enhancement properties but also minimizes the PDMS crosslinking through amino-complexed reaction between PEI and Pt catalysts.The prepared dielectric elastomers have aεr of 7.2@10^(3)Hz and Y of 1.14 MPa,leading to an actuation strain of 22.27%at 35 V/μm.Hence,incorporating such novel hybrids based on dual amino-complexed effect on both matrix and particles sufficiently promotes the actuated performance of dielectric elastomers.
基金supported by grants from the Research Grants Council of the Hong Kong Special Administrative Region,China(Poly U25216121,Poly U15303219)the National Natural Science Foundation of China for Young Scholar(52102310)the Research Committee of the Hong Kong Polytechnic University(A-PB1 M,1-BBXK,1-CD4 M,and G-UAMV)。
文摘High-energy lithium-sulfur batteries(LSBs)have experienced relentless development over the past decade with discernible improvements in electrochemical performance.However,a scrutinization of the cell operation conditions reveals a huge gap between the demands for practical batteries and those in the literature.Low sulfur loading,a high electrolyte/sulfur(E/S)ratio and excess anodes for lab-scale LSBs significantly offset their high-energy merit.To approach practical LSBs,high loading and lean electrolyte parameters are needed,which involve budding challenges of slow charge transfer,polysulfide precipitation and severe shuttle effects.To track these obstacles,the exploration of electrocatalysts to immobilize polysulfides and accelerate Li-S redox kinetics has been widely reported.Herein,this review aims to survey state-of-the-art catalytic materials for practical LSBs with emphasis on elucidating the correlation among catalyst design strategies,material structures and electrochemical performance.We also statistically evaluate the state-of-the-art catalyst-modified LSBs to identify the remaining discrepancy between the current advancements and the real-world requirements.In closing,we put forward our proposal for a catalytic material study to help realize practical LSBs.
基金supported by the Biological Resources Programme,Chinese Academy of Sciences(Grant No.KFJ-BRP-007)the National Natural Science Foundation of China(Grant No.32072620)the Shanghai Landscaping Administration Bureau(Grant No.G202405,G192415,G192407,G182412)。
文摘American lotus(Nelumbo lutea)is one of the two species in Nelumbo and has only yellow flower.Identification of total flavonoids showed wild American lotus contained almost only flavonols with quercetin 3-O-glucuronide to be the dominant pigment.The variation tendency of the total flavonol content was coincident with yellow color variation of petals during flower development.To understand the mechanism of accumulation and constituent of pigments in petals,three pivotal genes,NlFLS1,NlFLS2 and NlFLS3,which were predicted to encode flavonol synthases were isolated and characterized by analyses of basic bioinformatics,temporal and spatial expression patterns and enzymatic activity.Their temporal expression levels showed the same variation tendency,which was also consistent with the development-dependent variation of total flavonol content.Spatial expression patterns indicated the three genes should function in petals.All the three proteins were demonstrated to be bifunctional dioxygenase,possessing both flavonol synthase activity and flavanone 3-hydroxylase activity.Besides,other flavonol biosynthesis related genes were also investigated on their expression levels to give more clues on the mechanism.Substrate preferences of the three FLSs,substrate competitions between the FLSs and other flavonol biosynthesis related enzymes,and the greatly differential expression levels between F3’H(flavonoid 3-hydroxylase)and F3’5’H(flavonoid 3,5-hydroxylase)contributed to the flavonol constituent in the petals of America lotus,namely abundant quercetin-derivatives while very few kaempferol-derivatives and myricetin-derivatives.
文摘Diabetes mellitus, a type of chronic metabolic disease, is occurring more frequently and causes severe threats to human health. In vivo, exercise can stimulate skeletal muscle cells to secrete and release myokines into blood circulation, which will participate in metabolism and act on multiple organs or systems. Recently, the relationship between myokines and diabetes mellitus was a hot research topic, and myokines may be potential targets for the diagnosis, monitoring, prevention and treatment of diabetes mellitus. In this review, we elucidated the multiple effects of common myokines in the pathogenesis and therapy of diabetes mellitus, which will provide a theoretical foundation of the mechanism in the positive effects of exercises on humans.
基金supported by the funds from National Natural Science Foundation of China (31570199)the project of Shanghai Landscaping Administration Bureau (F122416)
文摘Begonia, one of the most diverse plant taxa and the fifth or sixth largest angiosperm genus, consists of over1800 accepted species. The number of species recognized within this genus has greatly increased over the past 20 years, rising from 80 to 200 species in China alone. Based on recent field surveys, the number of begonia species in China is predicted to be between 250 and 300. Given the large number of begonia species that still remain to be described, further taxonomical work is urgently required. This is especially true for Chinese Begonia, in which there is a huge diversity of habitat, habit, plant size, leaf type, flower and fruit morphology, and most species are narrowly distributed in isolated habitats that are subject to negative disturbances from climate change, as well as agricultural and industrial activities. Although the conservation status for the majority of species has been evaluated using the standards of the International Union for Conservation of Nature, the results don't represent the truth in many species, and also about11.5% of which are data-absent. In addition, illegal collection and over-harvesting of wild begonias for ornamental or medicinal use has increased due to the rapid development of internet commerce. Far more often than predicted, these species should be categorized as rare and endangered and require immediate protection. Ex situ conservation of Chinese begonias started in 1995 and over 60% of the total species have been so far introduced into cultivation by several major botanical gardens in China. However, only few research institutions, limited funds and human resources have been involved in Begonia conservation;moreover, no project has conducted reintroduction. Therefore, more conservation-based work remains to be done. Improved conservation of Chinese begonias in the future depends on further field survey, an improved understanding of population diversity, and integrative approaches, including in situ and ex situ conservation, seed banking, and plant reintroduction. Species-targeted conservation zones should be established for endangered species excluded from the existing nature reserves. Additionally, laws pertaining to plant protection should be extended to prevent the illegal collection and transaction of wild plants, particularly for those species with unique habitats and small populations.
基金financially supported by grants from the National Key R&D Program of China(2018YFD0400204)the National Natural Science Foundation of China(81974503,81871095)the Key International S&T Cooperation Program of China(2016YFE113700)。
文摘Previous study have demonstrated that a compound composed of water-soluable Ganoderma lucidum polysaccharides(GLP)and Polyporus umbellatus polysaccharides(PUP)in a ratio of 3:1 named GPP enhances innate immune function in mice through enhancing the function of macrophage cells and activity of natural killer(NK)cells.Here in our research,we further investigated the effect of GPP on the diversity and composition of intestinal flora,and explored its effect on colitis model mice.The immunoregulatory verification experiments of GPP were conducted in both normal and DSS-induced mice model.Our research showed that GPP increased the diversity of intestinal microorganisms in mice with the extension of administration time.Daily GPP intake attenuated DSS-induced colon injury,protected the splenic lymphocyte proliferation ability,enhanced the serum hemolysin synthesis,and increased peripheral phagocytes and NK cell activity in model mice.Comparisons of the predominant gene pathways of the bacterial microbiota showed that DNA repair and recombination,base mismatch repair pathways was stronger in GPP-treatment group than in control group,indicating the possible molecular mechanisms of immune function regulation.Our study showed that GPP regulated immune function in both health and colitis model,and had a positive effect on maintaining intestinal flora homeostasis.
基金Supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA23050301)the Special Exchange Program from the Chinese Academy of Sciences,the National Natural Science Foundation of China(Nos.41576152,41876138)+1 种基金the Instrument Developing Project of the Chinese Academy of Sciences(No.YJKYYQ20180047)the Key Research and Development Program of Yantai(No.2018ZHGY073)。
文摘Aurelia spp.ephyrae have been reported to form blooms in sea cucumber aquaculture ponds in the Bohai and Yellow Seas.To identify the species,we carried out a genetic analysis of Aurelia spp.ephyrae and medusae based on mitochondrial 16 S rRNA gene.Samples offour Aurelia sp.ephyrae populations were collected in sea cucumber aquaculture ponds and samples offour Aurelia sp.medusae populations were collected in coastal waters.Using a BLASTn search,we found that both the ephyrae collected in the aquaculture ponds and medusae collected in coastal waters belong to Aurelia coerulea.Seventeen haplotypes were recovered from the 16 S rRNA gene.The overall haplotype diversity and nucleotide diversity of the 166 A.coerulea individuals were 0.686%and 0.329%,respectively,indicating high haplotype diversity and low nucleotide diversity.Moreover,the haplotype diversity of ephyrae populations were generally lower than that of medusae populations with close sampling points.The genetic differentiation between ephyrae populations collected in the sea cucumber aquaculture ponds and A.coerulea medusae collected in coastal waters was not significant,suggesting the ephyrae populations in the sea cucumber culture ponds were part of the same genetic group as the medusae populations in the coastal waters.Phylogeographic analysis of the 16 S rRNA region revealed that there was no significant correlation between the haplotypes and the geographic distribution of populations.Pairwise fixation index values showed significant genetic differentiation and limited gene flow between A.coerulea population of Weifang and other locations.
基金This study was supported by the National Natural Science Foundation of China program(81774273 and 82004275)Beijing Municipal Science and Technology Commission(Z161100001816003).
文摘Objective:Previous studies have found that Qidi Tangshen granules(QDTS),a combination therapy of supplementing essence(Tianjing,TJ)and unblocking the collaterals(Tongluo,TL),can reduce kidney damage in db/db mice.This study aimed to explore the effect of QDTS and their separate prescriptions on podocytes in mice with diabetic nephropathy.Methods:The db/db mice were used in this experiment as an animal model,while wild-type C57BL/6J mice were used as normal controls.At the age of 12 weeks,the db/db mice were randomly divided into 5 groups(db/db,db/dbþvalsartan,db/dbþQDTS,db/dbþTJ and db/dbþTL).The urine albumin excretion ratio(UAE)was measured by enzyme-linked immunosorbent assay before and after the intervention.The ultrastructure of the kidney podocytes was observed by transmission electron microscopy.The protein expression levels of nephrin and desmin were detected by immunohistochemistry.Results:QDTS and their separate prescriptions significantly decreased the UAE and attenuated the renal pathological injury.QDTS and their separate prescriptions also reduced the fusion rate of the foot processes and increased the expression of nephrin protein.In contrast,QDTS and their separate prescriptions(TJ and TL)reduced the expression level of desmin protein.Conclusion:QDTS and their separate prescriptions might reduce diabetes-induced renal injury by reducing podocyte damage.The therapeutic effect of QDTS was more pronounced than TJ and TL.
基金supported by the Guangxi Science and Technology Key Research and Development Program(AB16450012)。
文摘The spreading of cancer cells from the primary tumor site to other parts of the body,known as metastasis,is the leading cause of cancer recurrence and mortality in patients with triple-negative breast cancer(TNBC).Overexpression of epidermal growth factor receptor(EGFR)is observed in approximately 70%of TNBC patients.EGFR is crucial for promoting tumor metastasis and associated with poor prognosis.Therefore,it is vital to identify effective therapeutic strategies targeting EGFR inhibition.Ononin,an isoflavonoid found in various plants,such as clover and soybeans,has been shown to have anticancer properties in several cancers.In the present study,we aimed to investigate the effects of ononin on TNBC lung metastasis and the associated molecular pathways.We used various assays,including cell viability,colony formation,Transwell,wound healing,ELISA,Western blotting,and staining techniques,to achieve this objective.The results demonstrated that ononin effectively suppressed cellular proliferation and induced apoptosis,as evidenced by the cell viability assay,colony formation assay,and expression of apoptosis markers,and reduced the metastatic capabilities of TNBC cells.These effects were achieved through the direct suppression of cell adhesion,invasiveness and motility.Furthermore,in TNBC xenograft lung metastatic models,ononin treatment significantly reduced tumor growth and lung metastasis.Additionally,ononin reversed the epithelial-mesenchymal transition(EMT)by downregulating the expression of EMT markers and matrix metalloproteinases,as confirmed by Western blot analysis.Furthermore,ononin treatment reduced EGFR phosphorylation and suppressed the PI3K,Akt,and m TOR signaling pathways,which was further confirmed using EGFR agonists or inhibitors.Importantly,ononin treatment did not exert any toxic effects on liver or kidney function.In conclusion,our findings suggest that ononin is a safe and potentially therapeutic treatment for TNBC metastasis that targets the EGFRmediated PI3K/Akt/m TOR pathway.Further studies are warranted to validate its efficacy and explore its potential clinical applications.
基金supported by the Natural Science Foundation of Chinathe National Key R&D Program of ChinaChinese Academy of Sciences through research projects(Grant Nos.2018YFA0305700,2021YFA1401-800,and XDB33010200)。
文摘The binary polyhydrides of heavy rare earth lutetium that shares a similar valence electron configuration to lanthanum have been experimentally discovered to be superconductive.The lutetium polyhydrides were successfully synthesized at high pressure and high temperature conditions using a diamond anvil cell in combinations with the in-situ high pressure laser heating technique.The resistance measurements as a function of temperature were performed at the same pressure of synthesis in order to study the transitions of superconductivity(SC).The superconducting transition with a maximum onset temperature(Tc)71 K was observed at pressure of 218 GPa in the experiments.The Tcdecreased to 65 K when pressure was at 181 GPa.From the evolution of SC at applied magnetic fields,the upper critical field at zero temperatureμ0Hc2(0)was obtained to be~36 T.The in-situ high pressure X-ray diffraction experiments imply that the high TcSC should arise from the Lu4H23phase with Pm3n symmetry that forms a new type of hydrogen cage framework different from those reported for previous light rare earth polyhydride superconductors.
基金This work was supported by the National Natural Science Foundation of China(Nos.51872011,51902011,and 22005013)The authors thank the BL14W1 in the Shanghai Synchrotron Radiation Facility(SSRF),BL10B and BL12B in the National Synchrotron Radiation Laboratory(NSRL)for help with characterizations.
文摘Interface regulation plays a key role in the electrochemical performance for biosensors.By controlling the interfacial interaction,the electronic structure of active species can be adjusted effectively at micro and nano-level,which results in the optimal reaction energy barrier.Herein,we propose an interface electronic engineering scheme to design a strongly coupled 1T phase molybdenum sulfide(1T-MoS2)/MXene hybrids for constructing an efficient electrocatalytic biomimetic sensor.The local electronic and atomic structures of the 1T-MoS2/Ti3C2TX are comprehensively studied by synchrotron radiation-based X-ray photoelectron spectroscopy(XPS),as well as X-ray absorption spectroscopy(XAS)at atomic level.Experiments and theoretical calculations show that there are interfacial stresses,atomic defects and adjustable bond-length between MoS2/MXene nanosheets,which can significantly promote biomolecular adsorption and rapid electron transfer to achieve excellent electrochemical activity and reaction kinetics.The 1T-MoS2/Ti3C2TX modified electrode shows ultra high sensitivity of 1.198μA/μM for dopamine detection with low limit of 0.05μM.We anticipate that the interface electronic engineering investigation could provide a basic idea for guiding the exploration of advanced biosensors with high sensitivity and low detection limit.
基金This work was supported by the National Natural Science Foundation of China(Nos.51872011,51902011,and 22005013)Beijing Natural Science Foundation(No.2212018)+1 种基金Beijing Institute of Technology Research Fund Program for Young Scholars(No.2022CX01011)Chinese Academy of Sciences。
文摘Single-atom nanozymes(SAzymes)are emerging as promising alternatives to mimic natural enzyme,which is due to high atomic utilization efficiency,well-defined geometric,and unique electronic structure.Herein,Fe single atoms supported on Ti_(3)C_(2)T_(x)(Fe-SA/Ti_(3)C_(2)T_(x))with intrinsic peroxidase activity is developed,further constructing a sensitive Raman sensor array for sensing of five antioxidants.Fe-SA/Ti_(3)C_(2)T_(x)shows excellent peroxidase-like performance in catalyzing the oxidation of 3,3',5,5'-tetramethylbenzidine(TMB)with colorimetric reactions.X-ray adsorption fine structure(XAFS)reveals that the electron transport between the Ti_(3)C_(2)T_(x)and Fe atoms occurs along Fe-O-Ti ligands,meanwhile the density functional theory(DFT)calculations confirm the spontaneous dissociation of H_(2)O_(2)and the formation of OH radicals.Furthermore,the peroxidase-like Fe-SA/Ti_(3)C_(2)T_(x)was used as surface enhanced Raman scattering(SERS)substrate of oxidized TMB(TMB+)and achieved satisfied signal amplification performance.Using the blocking effects of free radical reactions,one-off identification of 5 antioxidants,including ascorbic acid(AA),uric acid(UA),glutathione(GSH),melatonin(Mel),and tea polyphenols(TPP),could be realized with this high identifiable catalytic property.This principle could realize 100%distinguish accuracy combined with linear discriminant analysis(LDA)and heat map data analysis.A wide detection concentration ranges from 10^(-8)to 10^(-3)M for five antioxidants was also achieved.
基金supported by Beijing Natural Science Foundation(No.2212018)the National Natural Science Foundation of China(No.21801015).
文摘Owing to the unique coordination environment and high atom utilization efficiency,single atom catalysts have been considered as an ideal artificial enzyme to mimic natural enzymes.Herein,single-atom Fe nanozyme anchored on N-doped Ti_(3)C_(2)Tx(Fe SA/N-Ti_(3)C_(2)Tx)with asymmetrically coordinated Fe-N_(1)C_(2)configuration is synthesized by vacancy capture and heteroatom doping strategy,which exhibits excellent peroxidase-like activity.Based on the results of peroxidase catalytic kinetics and X-ray adsorption fine spectroscopy,the Fe-N_(1)C_(2)active sites in Fe SA/N-Ti_(3)C_(2)Tx are responsible for the excellent performance.Furthermore,the developed Fe SA/N-Ti_(3)C_(2)Tx can be employed to quantitative detection of melatonin(MT),which shows a wide linear detection range(0.01-100μM)and an excellent detection limit(7.3 nM)in buffer,0.01-100μM and 7.8 nM in serum samples.Our work proves that MXene-based single atoms can be promising nanozyme in the field of bioassays.
基金supported by the Ministry of Science and Technology of China(2018YFA0703200 and 2022YFB3603800)the National Natural Science Foundation of China(21875259,52233010,51725304,61890943 and 22021002)+4 种基金the Chinese Academy of Sciences Project for Young Scientists in Basic Research(YSBR-053)the Youth Innovation Promotion Association of the Chinese Academy of Sciencesthe National Program for Support of Top-notch Young ProfessionalsBeijing National Laboratory for Molecular Sciences(BNLMS-CXXM-202012)the Key Research Program of the Chinese Academy of Sciences(XDPB13)。
