The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides...The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)Fe.In this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the China Institute of Atomic Energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy degrader.For particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the spectrograph.Finally,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS system.These results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)Ni.The sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated.展开更多
Background:The specific impact of sphingolipid metabolism on developing hepatocellular Carcinoma(HCC)remains unclear.This study aims to explore the relationship between sphingolipid metabolism and HCC prognosis,immune ...Background:The specific impact of sphingolipid metabolism on developing hepatocellular Carcinoma(HCC)remains unclear.This study aims to explore the relationship between sphingolipid metabolism and HCC prognosis,immune response,and drug sensitivity.Methods:Data were obtained from The Cancer Genome Atlas(TCGA)-Hepatocellular Carcinoma(LIHC)and Gene Expression Omnibus(GEO,GSE14520 datasets).47 sphingolipid metabolism genes were obtained from the Kyoto Encyclopedia of Genes and Genomes(KEGG)database.After classifying HCC samples using the Non-negative Matrix Factorization(NMF)clustering method,differentially expressed genes were screened.Then,8 risk genes were obtained by univariate analysis,survival random forest reduction and lasso analysis.The expression of 8 risk genes was verified in vitro.Results:8 risk genes were used to construct the Sphingolipid score model.High-Sphingolipid score predicted poor prognosis of HCC patients.Sphingolipid score was associated with immune checkpoints(IL-1B,TLR4,TGFB1,and IL-10),immune cells(Th2,Treg,MDSC,Neutrophil,Fibroblasts and macrophage),and MAPK Cascade.In the High-Sphingolipid score group,a significantly higher proportion of patients with TP53(p53)mutations was significantly higher(56%).Furthermore,patients with a high-Sphingolipid score were predicted to have a higher sensitivity to chemotherapy drugs.In vitro validation showed that compared with normal liver cells LX-2,TRIM47,and S100A9 significantly increased in liver cancer cells Hep G2,MHCC-97H,and Hep3B2.1-7,while SLC1A7,LPCAT1,and CFHR4 significantly decreased.Silencing TRIM47 reduced the proliferation and promoted apoptosis.The levels of ceramide synthesis-related indexes(CERS1,CERS6,CERS5,and SPTLC2)increased,and the ACER3 related to catalytic hydrolysis decreased.Conclusion:We constructed a sphingolipid metabolism-related prognostic signature(Sphingolipid score)based on 8 risk genes.TRIM47 may affect the development of liver cancer by regulating the relevant indicators of ceramide synthesis and catalytic hydrolysis.展开更多
BACKGROUND The clinical effects and detailed roles of long non-coding RNA(LncRNA)steroid receptor RNA activator 1(SRA1)in esophageal squamous cell carcinoma(ESCC)remain ambiguous.In the present study,the complementary...BACKGROUND The clinical effects and detailed roles of long non-coding RNA(LncRNA)steroid receptor RNA activator 1(SRA1)in esophageal squamous cell carcinoma(ESCC)remain ambiguous.In the present study,the complementary sites between lncRNA SRA1,miRNA-363-5p,and phospholysine phosphohistidine inorganic pyrophosphate phosphatase(LHPP)predicted via bioinformatics analysis stimulated us to hypothesize that miRNA-363-5p/LHPP axis might be required for SRA1-mediated ESCC progression.AIM To investigate the molecular events of SRA1 in the malignant behavior in ESCC.METHODS Thirty-eight ESCC tissues and paired adjacent normal tissues were acquired.SRA1 expression was detected in ESCC tissues and cell lines using quantitative reverse transcription-polymerase chain reaction.Cell counting Kit-8 assay,transwell invasion assay,glycolysis assay,and xenograft tumor model were performed to address the malignant biological behaviors of ESCC cells after the introduction of SRA1.The t-test and theχ2 test were used for comparison between groups.Survival curve analysis was performed using the Kaplan-Meier method.RESULTS SRA1 downregulation was identified in ESCC.ESCC patients exhibiting a low SRA1 expression faced shorter overall survival than those with a high SRA1 expression.The introduction of SRA1 inhibited cell proliferation,glucose uptake,and lactate production in ESCC.In vivo,the growth of ESCC was hindered by SRA1 overexpression.Then,SRA1 overexpresses the LHPP by inhibiting miRNA-363-5p.Lastly,the introduction of small interfering RNA si-LHPP or miRNA-363-5p mimic could abrogate the inhibition roles triggered by SRA1.CONCLUSION SRA1 inhibits the oncogenicity of ESCC via miRNA-363-5p/LHPP axis.The SRA1/miRNA-363-5p/LHPP pathway may be a therapeutic target for ESCC.展开更多
This study proposes a double-rough-walled fracture model to represent the natural geometries of rough fractures.The rough surface is generated using a modified successive random additions(SRA)algorithm and the apertur...This study proposes a double-rough-walled fracture model to represent the natural geometries of rough fractures.The rough surface is generated using a modified successive random additions(SRA)algorithm and the aperture distribution during shearing is calculated using a mechanistic model.The shear-flow simulations are performed by directly solving the Navier-Stokes(NS)equations.The results show that the double-rough-walled fracture model can improve the accuracy of fluid flow simulations by approximately 14.99%-19.77%,compared with the commonly used single-rough-walled fracture model.The ratio of flow rate to hydraulic gradient increases by one order of magnitude for fluids in a linear flow regime with increment of shear displacement from 2.2 mm to 2.6 mm.By solving the NS equations,the inertial effect is taken into account and the significant eddies are simulated and numerically visualized,which are not easy to be captured in conventional experiments.The anisotropy of fluid flow in the linear regime during shearing is robustly enhanced as the shearing advances;however,it is either increased or decreased for fluids in the nonlinear flow regime,depending on the geometry of shear-induced void spaces between the two rough walls of the fracture.The present study provides a method to represent the real geometry of fractures during shearing and to simulate fluid flow by directly solving the NS equations,which can be potentially utilized in many applications such as heat and mass transfer,contaminant transport,and coupled hydro-thermo-mechanical processes within rock fractures/fracture networks.展开更多
Electrochemical CO_(2)reduction to formate is a promising approach to store renewable electricity and utilize CO_(2).Tin oxide catalysts are efficient catalysts for this process,while the mechanisms underneath,especia...Electrochemical CO_(2)reduction to formate is a promising approach to store renewable electricity and utilize CO_(2).Tin oxide catalysts are efficient catalysts for this process,while the mechanisms underneath,especially the existence and role of oxidized tin species under CO2 electroreduction conditions remain unclear.In this work,we provide strong evidence on the presence of oxidized tin species on both SnO_(2)and Sn during CO_(2)reduction via in situ surface‐enhanced Raman spectroscopy,while in different nature.Reactivity measurements show similar activity and selectivity to formate production on SnO_(2)and Sn catalysts.Combined analysis of Raman spectra and reactivity results suggests that Sn(IV)and Sn(II)oxide species are unlikely the catalytic species in CO_(2)electroreduction to formate.展开更多
Feather, as a by-product of the poultry industry, has long been treated as a solid waste, which causes environ- mental and economic problems. In this work, the hydrolyzed feather keratin (HFK) was extracted from the...Feather, as a by-product of the poultry industry, has long been treated as a solid waste, which causes environ- mental and economic problems. In this work, the hydrolyzed feather keratin (HFK) was extracted from the chicken feather using a cost-effective method of alkali-extraction and acid-precipitation by applying urea and sodium sulfide. The aim was development and characterization of the eco-friendly films based on the HFK with variable glycerol contents by a thermoplastic process. The thermal analysis showed that high temperature and high pres- sure improved the compatibility between the glycerol and the HFI( molecules. Also it was shown that the addi- tion of water is necessary in the hot-pressing process of films, The FT-IR analysis indicated that the formation of the new hydrogen bonds between HFK and glycerol. By increasing the glycerol content, the film tensile strength (orb ) decreases from 10,5 MPa to 5.7 MPa and the solubility increases from 15.3% to 20.9%, while the elongation at break (εb) achieves the maximum value of 63,8% for the film with 35% glycerol. The swelling was just below 16.9% at 25 ℃ for 24 h, suggesting a good stability of the films in water. The water vapor permeability (WVP) varied between 3.02 x 10 ^10g. m 2. s-1 . pa-1 and 4.11 x 10-10g · m-2 · s-1 · Pa-1 for the films with 20%and 40% glycerol, respectively. The HFK film was uniform, translucent and tough, which could be used in packaging and agricultural field.展开更多
An experimental and numerical study was carried out to investigate the solute removal process through a large-scale fracture plane considering different flow paths and hydraulic head differences.The visualization tech...An experimental and numerical study was carried out to investigate the solute removal process through a large-scale fracture plane considering different flow paths and hydraulic head differences.The visualization techniques were utilized in the experiment to capture the removal process images,which were then transferred to binary images.The variations in dimensionless concentration,which is defined as saturation of solute phase,were analyzed.With increasing hydraulic head difference,the speed of solute removal increases and the dimensionless concentration decreases.The flow paths result in different solute distribution patterns and different mechanisms for solute removal such as advection and diffusion,thus the curves of dimensionless concentration versus time are different.The dimensionless concentration over time decreases from approximately 1,which is smaller than 1 due to the existence of bubbles,to approximately 0,which is larger than 0 because the folds of the background are dealt as“solute”.A significant longer time is needed to achieve a certain fixed dimensionless concentration for a smaller hydraulic head difference.With the finite element software COMSOL multiphysics,the solute removal process,flow velocity fields,flow streamlines,as well as the hydraulic pressure fields were analyzed,which shows a good consistency with the experimental results.In practical engineering,when the solute pollutes the underground environment,the removal ability can be more significantly enforced by immediately applying a larger hydraulic head difference along a longer distance between the inlet and outlet boundaries.展开更多
In this study,carboxymethylation,which introduces carboxyl groups to hydroxyl sites in pulp fibers,was used as a pretreatment before mechanical nanofibrillation.The carboxyl group content of the pulp fibers was greatl...In this study,carboxymethylation,which introduces carboxyl groups to hydroxyl sites in pulp fibers,was used as a pretreatment before mechanical nanofibrillation.The carboxyl group content of the pulp fibers was greatly affected by the dosage of chloroacetic acid and the reaction temperature.During the following fibrillation process,it was found that pulp fibers with higher carboxyl group content exhibited higher water holding capacities and smaller dimensions.A more homogenous structure with a higher amount of individual fibrils was also observed in FE-SEM images of pulp fibers with high carboxyl group content.This can be explained by a high ionic group content in the fiber wall resulting in lower delamination resistance,making the fibrils easier to separate.Carboxymethylation pretreatment as a facilitator of fibrillation in cellulosic pulps is an efficient way to obtain cellulose nanofibrils and consequently decrease the energy consumption of the process.展开更多
In this paper, the totally non-positive matrix is introduced. The totally non-positive completion asks which partial totally non-positive matrices have a completion to a totally non-positive matrix. This problem has. ...In this paper, the totally non-positive matrix is introduced. The totally non-positive completion asks which partial totally non-positive matrices have a completion to a totally non-positive matrix. This problem has. in general, a negative answer. Therefore, our question is for what kind of labeled graphs G each partial totally non-positive matrix whose associated graph is G has a totally non-positive completion? If G is not a monotonically labeled graph or monotonically labeled cycle, we give necessary and sufficient conditions that guarantee the existence of the desired completion.展开更多
The fluid-structure interaction of the oscillating bubble and floating body with circular hole is essentially the nonlinear coupling problem among the incomplete movable boundary,free surface and bubble.This problem i...The fluid-structure interaction of the oscillating bubble and floating body with circular hole is essentially the nonlinear coupling problem among the incomplete movable boundary,free surface and bubble.This problem is particularly complicated in bubble dynamics.Combined with the volume of fluid method,the Eulerian finite element method is employed to deal with the fluid movement.Based on the improved penalty immersed boundary method,the transient axisymmetric numerical model is established in this paper,considering the fluid-structure interaction effect.The results of simulation are consistent with those of the electric discharge bubble experiment and explosion experiment.Subsequently,considering the influence of the hole size,floating body density,explosive location,and buoyancy,this complex fluid-structure interaction problem is analyzed systematically.Through numerical simulation,we get some new conclusions.When the radius of the hole Rh less than the maximum radius of the oscillating bubble,the changes in the whole system are incredibly intense,and the free surface crushing will emerge.The energy of the bubble acts more on the radial direction of the floating body,when the explosive location parameter is small.When the floating body has the same density as the water,the multiple spike skirt is displayed vividly.And the buoyancy of fluid can produce a lifting effect on the floating body.展开更多
Although CRISPR/Cas9 has been widely used in insect gene editing,the need for the microinjection of preblastoderm embryos can preclude the technique being used in insect species with eggs that are small,have hard shel...Although CRISPR/Cas9 has been widely used in insect gene editing,the need for the microinjection of preblastoderm embryos can preclude the technique being used in insect species with eggs that are small,have hard shells,and/or are difficult to collect and maintain outside of their normal environment.Such is the case with Sogatella furcifera,the white-backed planthopper(WBPH),a significant pest of Oryza sativa(rice)that oviposits inside rice stems.Egg extraction from the stem runs the risk of mechanical damage and hatching is heavily influenced by the micro-environment of the rice stem.To bypass these issues,we targeted embryos prior to oviposition via direct parental(DIPA)-CRISPR,in which Cas9 and single-guide RNAs(sgRNAs)for the WBPH eye pigment gene tryptophan 2,3-dioxygenase were injected into the hemocoel of adult females.Females at varying numbers of days posteclosion were evaluated to determine at what stage their oocyte might be most capable of taking up the gene-editing components.An evaluation of the offspring indicated that the highest G0 gene-edited efficacy(56.7%)occurred in females injected 2 d posteclosion,and that those mutations were heritably transmitted to the G1 generation.This study demonstrates the potential utility of DIPA-CRISPR for future gene-editing studies in non-model insect species and can facilitate the development of novel pest management applications.展开更多
In the present study,the antioxidant and anti-human liver cancer(HepG2)cells effects of bioactive peptides from cowhide collagen(BPCC)were evaluated.BPCC exhibited significant scavenging effect on l,1-diphenyl-2-picry...In the present study,the antioxidant and anti-human liver cancer(HepG2)cells effects of bioactive peptides from cowhide collagen(BPCC)were evaluated.BPCC exhibited significant scavenging effect on l,1-diphenyl-2-picrylhydrazyl(DPPH)radicals((60.09±3.51)%),2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS)radicals((77.40±3.10)%)and hydroxyl radicals((56.00±2.30)%)as well as strong reducing power(0.320士0.025).Meanwhile,BPCC effectively protected biomacromolecules including proteins,lipids and DNA from oxidative damage induced by Cu^(2+)H_(2)O_(2)and 2,2'-azobis(2-methylpropionamidine)dihydrochloride(AAPH).Moreover,BPCC significantly inhibited cell viability of HepG2 cells in a dose-dependent manner with an estimated IC_(50)of 7.61 mg/mL.The results of 4',6-diamidino-2-phenylindole(DAPI)and acridine:orange/ethidium bromide(AO/EB)staining demonstrated the apoptotic morphological changes and cell mediated death in BPCC treated HepG2 cells.In addition,BPCC induced decrease of mitochondrial membrane potential(MMP)in HepG2 cells.Therefore,the present finding proved that BPCC encompasses significant antioxidant activity and anticancer property on HepG2 cells and can be used as alternative food antioxidants for cancer prevention benefits.展开更多
It is significant to research the impact resistance properties of hydraulic support due to its key support role in the fully mechanized mining face.However,it is difficult for the entire hydraulic support to implement...It is significant to research the impact resistance properties of hydraulic support due to its key support role in the fully mechanized mining face.However,it is difficult for the entire hydraulic support to implement the impact experiment underground and analyze the response characteristic.Therefore,a dynamic impact experiment for the entire hydraulic support was proposed in this paper,where a 1:2 reducedscale model of hydraulic support was designed and its response characteristics under dynamic impact load were analyzed.Firstly,a comprehensive monitoring scheme was proposed to achieve an effective monitoring for dynamic response of hydraulic support.Secondly,a multi-scale impact experiment was carried out for the entire hydraulic support and dynamic behaviors of hydraulic support under the multi-scale impact load were revealed by experimental data.Then a dynamic impact experiment of the entire hydraulic support was simulated in ADAMS with the same experiment conditions,and the experimental and simulation data were verified mutually.Finally,the characteristics of energy conversion and dissipation of the entire experiment system after impact were analyzed.The experiment results showed that the impact resistance properties of hydraulic support largely depended on the initial support conditions and different vertical rigidities affected energy distribution proportion of the entire support system.展开更多
Guaranteed cost consensus analysis and design problems for high-dimensional multi-agent systems with time varying delays are investigated. The idea of guaranteed cost con trol is introduced into consensus problems for...Guaranteed cost consensus analysis and design problems for high-dimensional multi-agent systems with time varying delays are investigated. The idea of guaranteed cost con trol is introduced into consensus problems for high-dimensiona multi-agent systems with time-varying delays, where a cos function is defined based on state errors among neighboring agents and control inputs of all the agents. By the state space decomposition approach and the linear matrix inequality(LMI)sufficient conditions for guaranteed cost consensus and consensu alization are given. Moreover, a guaranteed cost upper bound o the cost function is determined. It should be mentioned that these LMI criteria are dependent on the change rate of time delays and the maximum time delay, the guaranteed cost upper bound is only dependent on the maximum time delay but independen of the Laplacian matrix. Finally, numerical simulations are given to demonstrate theoretical results.展开更多
n the area of naval architecture and ocean engineering,the research about the underwater xplosion problem is of great significance.To achieve prolonged simulation of near-free surface underwater explosion,the underwat...n the area of naval architecture and ocean engineering,the research about the underwater xplosion problem is of great significance.To achieve prolonged simulation of near-free surface underwater explosion,the underwater explosion transient numerical model is established in this paper based on compressible Eulerian finite element method(EFEM).Compared with Geers Hunter formula,EFEM is availably validated by simulating the free-field underwater xplosion case.Then,the bubble pulsation and flow field dynamic characteristics of the cases with different underwater explosive depth are compared in this work.Lastly,the height of the water hump and the pressure of flow flied are analyzed quantitatively through the simulation results.展开更多
Underwater target recognition is a key technology for underwater acoustic countermeasure.How to classify and recognize underwater targets according to the noise information of underwater targets has been a hot topic i...Underwater target recognition is a key technology for underwater acoustic countermeasure.How to classify and recognize underwater targets according to the noise information of underwater targets has been a hot topic in the field of underwater acoustic signals.In this paper,the deep learning model is applied to underwater target recognition.Improved anti-noise Power-Normalized Cepstral Coefficients(ia-PNCC)is proposed,based on PNCC applied to underwater noises.Multitaper and normalized Gammatone filter banks are applied to improve the anti-noise capacity.The method is combined with a convolutional neural network in order to recognize the underwater target.Experiment results show that the acoustic feature presented by ia-PNCC has lower noise and are wellsuited to underwater target recognition using a convolutional neural network.Compared with the combination of convolutional neural network with single acoustic feature,such as MFCC(Mel-scale Frequency Cepstral Coefficients)or LPCC(Linear Prediction Cepstral Coefficients),the combination of the ia-PNCC with a convolutional neural network offers better accuracy for underwater target recognition.展开更多
基金supported by the National Natural Science Foundation of China(Nos.12125509,12222514,11961141003,and 12005304)National Key Research and Development Project(No.2022YFA1602301)+1 种基金CAST Young Talent Support Planthe CNNC Science Fund for Talented Young Scholars Continuous support for basic scientific research projects。
文摘The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)Fe.In this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the China Institute of Atomic Energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy degrader.For particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the spectrograph.Finally,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS system.These results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)Ni.The sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated.
基金The work was supported by funds from The Science and Technology Project of Hangzhou City(Agriculture and Social Development,No.2016007)&(Agriculture and Social Development,No.20201231Y131)&(Social Development,No.20140633B57)The Science and Technology Project of Yuhang District,Hangzhou City(Nos.2017002&2014003)+2 种基金The Health Science and Technology Project of Hangzhou City(No.2015B32)Zhejiang Provincial Natural Science Foundation of China under Grant(No.LTGY23H160006)The Health Science and Technology Project of Zhejiang Province(No.2023XY009).
文摘Background:The specific impact of sphingolipid metabolism on developing hepatocellular Carcinoma(HCC)remains unclear.This study aims to explore the relationship between sphingolipid metabolism and HCC prognosis,immune response,and drug sensitivity.Methods:Data were obtained from The Cancer Genome Atlas(TCGA)-Hepatocellular Carcinoma(LIHC)and Gene Expression Omnibus(GEO,GSE14520 datasets).47 sphingolipid metabolism genes were obtained from the Kyoto Encyclopedia of Genes and Genomes(KEGG)database.After classifying HCC samples using the Non-negative Matrix Factorization(NMF)clustering method,differentially expressed genes were screened.Then,8 risk genes were obtained by univariate analysis,survival random forest reduction and lasso analysis.The expression of 8 risk genes was verified in vitro.Results:8 risk genes were used to construct the Sphingolipid score model.High-Sphingolipid score predicted poor prognosis of HCC patients.Sphingolipid score was associated with immune checkpoints(IL-1B,TLR4,TGFB1,and IL-10),immune cells(Th2,Treg,MDSC,Neutrophil,Fibroblasts and macrophage),and MAPK Cascade.In the High-Sphingolipid score group,a significantly higher proportion of patients with TP53(p53)mutations was significantly higher(56%).Furthermore,patients with a high-Sphingolipid score were predicted to have a higher sensitivity to chemotherapy drugs.In vitro validation showed that compared with normal liver cells LX-2,TRIM47,and S100A9 significantly increased in liver cancer cells Hep G2,MHCC-97H,and Hep3B2.1-7,while SLC1A7,LPCAT1,and CFHR4 significantly decreased.Silencing TRIM47 reduced the proliferation and promoted apoptosis.The levels of ceramide synthesis-related indexes(CERS1,CERS6,CERS5,and SPTLC2)increased,and the ACER3 related to catalytic hydrolysis decreased.Conclusion:We constructed a sphingolipid metabolism-related prognostic signature(Sphingolipid score)based on 8 risk genes.TRIM47 may affect the development of liver cancer by regulating the relevant indicators of ceramide synthesis and catalytic hydrolysis.
基金Supported by Innovative Team of Jiangsu Province,No.CXTDA2017042Jiangsu Provincial Medical Youth Talent,No.QNRC2016508In-Hospital Project of Taizhou People's Hospital,No.ZL201930.
文摘BACKGROUND The clinical effects and detailed roles of long non-coding RNA(LncRNA)steroid receptor RNA activator 1(SRA1)in esophageal squamous cell carcinoma(ESCC)remain ambiguous.In the present study,the complementary sites between lncRNA SRA1,miRNA-363-5p,and phospholysine phosphohistidine inorganic pyrophosphate phosphatase(LHPP)predicted via bioinformatics analysis stimulated us to hypothesize that miRNA-363-5p/LHPP axis might be required for SRA1-mediated ESCC progression.AIM To investigate the molecular events of SRA1 in the malignant behavior in ESCC.METHODS Thirty-eight ESCC tissues and paired adjacent normal tissues were acquired.SRA1 expression was detected in ESCC tissues and cell lines using quantitative reverse transcription-polymerase chain reaction.Cell counting Kit-8 assay,transwell invasion assay,glycolysis assay,and xenograft tumor model were performed to address the malignant biological behaviors of ESCC cells after the introduction of SRA1.The t-test and theχ2 test were used for comparison between groups.Survival curve analysis was performed using the Kaplan-Meier method.RESULTS SRA1 downregulation was identified in ESCC.ESCC patients exhibiting a low SRA1 expression faced shorter overall survival than those with a high SRA1 expression.The introduction of SRA1 inhibited cell proliferation,glucose uptake,and lactate production in ESCC.In vivo,the growth of ESCC was hindered by SRA1 overexpression.Then,SRA1 overexpresses the LHPP by inhibiting miRNA-363-5p.Lastly,the introduction of small interfering RNA si-LHPP or miRNA-363-5p mimic could abrogate the inhibition roles triggered by SRA1.CONCLUSION SRA1 inhibits the oncogenicity of ESCC via miRNA-363-5p/LHPP axis.The SRA1/miRNA-363-5p/LHPP pathway may be a therapeutic target for ESCC.
基金partially funded by National Natural Science Foundation of China(Grant Nos.51979272 and 51709260)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20170276).
文摘This study proposes a double-rough-walled fracture model to represent the natural geometries of rough fractures.The rough surface is generated using a modified successive random additions(SRA)algorithm and the aperture distribution during shearing is calculated using a mechanistic model.The shear-flow simulations are performed by directly solving the Navier-Stokes(NS)equations.The results show that the double-rough-walled fracture model can improve the accuracy of fluid flow simulations by approximately 14.99%-19.77%,compared with the commonly used single-rough-walled fracture model.The ratio of flow rate to hydraulic gradient increases by one order of magnitude for fluids in a linear flow regime with increment of shear displacement from 2.2 mm to 2.6 mm.By solving the NS equations,the inertial effect is taken into account and the significant eddies are simulated and numerically visualized,which are not easy to be captured in conventional experiments.The anisotropy of fluid flow in the linear regime during shearing is robustly enhanced as the shearing advances;however,it is either increased or decreased for fluids in the nonlinear flow regime,depending on the geometry of shear-induced void spaces between the two rough walls of the fracture.The present study provides a method to represent the real geometry of fractures during shearing and to simulate fluid flow by directly solving the NS equations,which can be potentially utilized in many applications such as heat and mass transfer,contaminant transport,and coupled hydro-thermo-mechanical processes within rock fractures/fracture networks.
文摘Electrochemical CO_(2)reduction to formate is a promising approach to store renewable electricity and utilize CO_(2).Tin oxide catalysts are efficient catalysts for this process,while the mechanisms underneath,especially the existence and role of oxidized tin species under CO2 electroreduction conditions remain unclear.In this work,we provide strong evidence on the presence of oxidized tin species on both SnO_(2)and Sn during CO_(2)reduction via in situ surface‐enhanced Raman spectroscopy,while in different nature.Reactivity measurements show similar activity and selectivity to formate production on SnO_(2)and Sn catalysts.Combined analysis of Raman spectra and reactivity results suggests that Sn(IV)and Sn(II)oxide species are unlikely the catalytic species in CO_(2)electroreduction to formate.
基金Supported by the National Natural Science Foundation of China(21176269,31371880,31401526)Higher School Science and Technology Innovation Project of Guangdong Province(2013KJCX0102)Science and Technology Plan Project of Guangdong Province(2013B010403029)
文摘Feather, as a by-product of the poultry industry, has long been treated as a solid waste, which causes environ- mental and economic problems. In this work, the hydrolyzed feather keratin (HFK) was extracted from the chicken feather using a cost-effective method of alkali-extraction and acid-precipitation by applying urea and sodium sulfide. The aim was development and characterization of the eco-friendly films based on the HFK with variable glycerol contents by a thermoplastic process. The thermal analysis showed that high temperature and high pres- sure improved the compatibility between the glycerol and the HFI( molecules. Also it was shown that the addi- tion of water is necessary in the hot-pressing process of films, The FT-IR analysis indicated that the formation of the new hydrogen bonds between HFK and glycerol. By increasing the glycerol content, the film tensile strength (orb ) decreases from 10,5 MPa to 5.7 MPa and the solubility increases from 15.3% to 20.9%, while the elongation at break (εb) achieves the maximum value of 63,8% for the film with 35% glycerol. The swelling was just below 16.9% at 25 ℃ for 24 h, suggesting a good stability of the films in water. The water vapor permeability (WVP) varied between 3.02 x 10 ^10g. m 2. s-1 . pa-1 and 4.11 x 10-10g · m-2 · s-1 · Pa-1 for the films with 20%and 40% glycerol, respectively. The HFK film was uniform, translucent and tough, which could be used in packaging and agricultural field.
基金supported by National Natural Science Foundation of China(Nos.51979272,51904290,51979156)the Natural Science Foundation of Jiangsu Province,China(No.BK20180663)State Key Laboratory for Geomechanics and Deep Underground Engineering,China University of Mining&Technology,China(No.SKLGDUEK1906).
文摘An experimental and numerical study was carried out to investigate the solute removal process through a large-scale fracture plane considering different flow paths and hydraulic head differences.The visualization techniques were utilized in the experiment to capture the removal process images,which were then transferred to binary images.The variations in dimensionless concentration,which is defined as saturation of solute phase,were analyzed.With increasing hydraulic head difference,the speed of solute removal increases and the dimensionless concentration decreases.The flow paths result in different solute distribution patterns and different mechanisms for solute removal such as advection and diffusion,thus the curves of dimensionless concentration versus time are different.The dimensionless concentration over time decreases from approximately 1,which is smaller than 1 due to the existence of bubbles,to approximately 0,which is larger than 0 because the folds of the background are dealt as“solute”.A significant longer time is needed to achieve a certain fixed dimensionless concentration for a smaller hydraulic head difference.With the finite element software COMSOL multiphysics,the solute removal process,flow velocity fields,flow streamlines,as well as the hydraulic pressure fields were analyzed,which shows a good consistency with the experimental results.In practical engineering,when the solute pollutes the underground environment,the removal ability can be more significantly enforced by immediately applying a larger hydraulic head difference along a longer distance between the inlet and outlet boundaries.
基金financial support from the National Key Research and Development Program of China (Grant No.2017YFB0307900)the National Natural Science Foundation of China (Grant No.31470602,31670595,31770628)the Taishan Scholars Program
文摘In this study,carboxymethylation,which introduces carboxyl groups to hydroxyl sites in pulp fibers,was used as a pretreatment before mechanical nanofibrillation.The carboxyl group content of the pulp fibers was greatly affected by the dosage of chloroacetic acid and the reaction temperature.During the following fibrillation process,it was found that pulp fibers with higher carboxyl group content exhibited higher water holding capacities and smaller dimensions.A more homogenous structure with a higher amount of individual fibrils was also observed in FE-SEM images of pulp fibers with high carboxyl group content.This can be explained by a high ionic group content in the fiber wall resulting in lower delamination resistance,making the fibrils easier to separate.Carboxymethylation pretreatment as a facilitator of fibrillation in cellulosic pulps is an efficient way to obtain cellulose nanofibrils and consequently decrease the energy consumption of the process.
基金The work was supported by the National Science Foundation of China (10571146).
文摘In this paper, the totally non-positive matrix is introduced. The totally non-positive completion asks which partial totally non-positive matrices have a completion to a totally non-positive matrix. This problem has. in general, a negative answer. Therefore, our question is for what kind of labeled graphs G each partial totally non-positive matrix whose associated graph is G has a totally non-positive completion? If G is not a monotonically labeled graph or monotonically labeled cycle, we give necessary and sufficient conditions that guarantee the existence of the desired completion.
基金The National Key R and D Program of China(2018YFC0308900)the National Natural Science Foundation of China(Grant No.51879050)+1 种基金the Industrial Technology Development Program(Grant No.JCKY2018604C010)the China Postdoctoral Science Foundation(Grant Nos.2016M600244,2018T110271).
文摘The fluid-structure interaction of the oscillating bubble and floating body with circular hole is essentially the nonlinear coupling problem among the incomplete movable boundary,free surface and bubble.This problem is particularly complicated in bubble dynamics.Combined with the volume of fluid method,the Eulerian finite element method is employed to deal with the fluid movement.Based on the improved penalty immersed boundary method,the transient axisymmetric numerical model is established in this paper,considering the fluid-structure interaction effect.The results of simulation are consistent with those of the electric discharge bubble experiment and explosion experiment.Subsequently,considering the influence of the hole size,floating body density,explosive location,and buoyancy,this complex fluid-structure interaction problem is analyzed systematically.Through numerical simulation,we get some new conclusions.When the radius of the hole Rh less than the maximum radius of the oscillating bubble,the changes in the whole system are incredibly intense,and the free surface crushing will emerge.The energy of the bubble acts more on the radial direction of the floating body,when the explosive location parameter is small.When the floating body has the same density as the water,the multiple spike skirt is displayed vividly.And the buoyancy of fluid can produce a lifting effect on the floating body.
基金supported by:the National Natural Science Foundation of China(grants 32370527,for PH,and 32260671,for MH)the Scientific Research Foundation of Guizhou University of China(grant 2017-33,for MH)+3 种基金the Program of Talent Cultivation of Guizhou University(grant(2019)05,for PH)the Science and Technology Support of Guizhou province(grant QKH(2017)2956,for MH)the Program of Introducing Talents of Discipline to Universities of China(111 Program,D20023)the Frontiers Science Center for Asymmetric Synthesis and Medicinal Molecules,Department of Education,Guizhou Province(Qianjiaohe KY number(2020)004).
文摘Although CRISPR/Cas9 has been widely used in insect gene editing,the need for the microinjection of preblastoderm embryos can preclude the technique being used in insect species with eggs that are small,have hard shells,and/or are difficult to collect and maintain outside of their normal environment.Such is the case with Sogatella furcifera,the white-backed planthopper(WBPH),a significant pest of Oryza sativa(rice)that oviposits inside rice stems.Egg extraction from the stem runs the risk of mechanical damage and hatching is heavily influenced by the micro-environment of the rice stem.To bypass these issues,we targeted embryos prior to oviposition via direct parental(DIPA)-CRISPR,in which Cas9 and single-guide RNAs(sgRNAs)for the WBPH eye pigment gene tryptophan 2,3-dioxygenase were injected into the hemocoel of adult females.Females at varying numbers of days posteclosion were evaluated to determine at what stage their oocyte might be most capable of taking up the gene-editing components.An evaluation of the offspring indicated that the highest G0 gene-edited efficacy(56.7%)occurred in females injected 2 d posteclosion,and that those mutations were heritably transmitted to the G1 generation.This study demonstrates the potential utility of DIPA-CRISPR for future gene-editing studies in non-model insect species and can facilitate the development of novel pest management applications.
基金supported by Shandong Provincial Natural Science Foundation,China(ZR2014CQ002)SDUT and Zibo City Integration Development Project(2017ZBXC004)。
文摘In the present study,the antioxidant and anti-human liver cancer(HepG2)cells effects of bioactive peptides from cowhide collagen(BPCC)were evaluated.BPCC exhibited significant scavenging effect on l,1-diphenyl-2-picrylhydrazyl(DPPH)radicals((60.09±3.51)%),2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS)radicals((77.40±3.10)%)and hydroxyl radicals((56.00±2.30)%)as well as strong reducing power(0.320士0.025).Meanwhile,BPCC effectively protected biomacromolecules including proteins,lipids and DNA from oxidative damage induced by Cu^(2+)H_(2)O_(2)and 2,2'-azobis(2-methylpropionamidine)dihydrochloride(AAPH).Moreover,BPCC significantly inhibited cell viability of HepG2 cells in a dose-dependent manner with an estimated IC_(50)of 7.61 mg/mL.The results of 4',6-diamidino-2-phenylindole(DAPI)and acridine:orange/ethidium bromide(AO/EB)staining demonstrated the apoptotic morphological changes and cell mediated death in BPCC treated HepG2 cells.In addition,BPCC induced decrease of mitochondrial membrane potential(MMP)in HepG2 cells.Therefore,the present finding proved that BPCC encompasses significant antioxidant activity and anticancer property on HepG2 cells and can be used as alternative food antioxidants for cancer prevention benefits.
基金supported by National Key R&D Program of China for the 13th Five-Year Plan(No.2017YFC0603005)National Natural Science Foundation of China(Nos.51874174and 51834006)。
文摘It is significant to research the impact resistance properties of hydraulic support due to its key support role in the fully mechanized mining face.However,it is difficult for the entire hydraulic support to implement the impact experiment underground and analyze the response characteristic.Therefore,a dynamic impact experiment for the entire hydraulic support was proposed in this paper,where a 1:2 reducedscale model of hydraulic support was designed and its response characteristics under dynamic impact load were analyzed.Firstly,a comprehensive monitoring scheme was proposed to achieve an effective monitoring for dynamic response of hydraulic support.Secondly,a multi-scale impact experiment was carried out for the entire hydraulic support and dynamic behaviors of hydraulic support under the multi-scale impact load were revealed by experimental data.Then a dynamic impact experiment of the entire hydraulic support was simulated in ADAMS with the same experiment conditions,and the experimental and simulation data were verified mutually.Finally,the characteristics of energy conversion and dissipation of the entire experiment system after impact were analyzed.The experiment results showed that the impact resistance properties of hydraulic support largely depended on the initial support conditions and different vertical rigidities affected energy distribution proportion of the entire support system.
基金supported by Shaanxi Province Natural Science Foundation of Research Projects(2016JM6014)the Innovation Foundation of High-Tech Institute of Xi’an(2015ZZDJJ03)the Youth Foundation of HighTech Institute of Xi’an(2016QNJJ004)
文摘Guaranteed cost consensus analysis and design problems for high-dimensional multi-agent systems with time varying delays are investigated. The idea of guaranteed cost con trol is introduced into consensus problems for high-dimensiona multi-agent systems with time-varying delays, where a cos function is defined based on state errors among neighboring agents and control inputs of all the agents. By the state space decomposition approach and the linear matrix inequality(LMI)sufficient conditions for guaranteed cost consensus and consensu alization are given. Moreover, a guaranteed cost upper bound o the cost function is determined. It should be mentioned that these LMI criteria are dependent on the change rate of time delays and the maximum time delay, the guaranteed cost upper bound is only dependent on the maximum time delay but independen of the Laplacian matrix. Finally, numerical simulations are given to demonstrate theoretical results.
基金The authors would like to acknowledge the support of the National Natural Science Foundation of China(Grant 11672081)the Industrial Technology Development Program(Grants JCKY2018604C010 and JCKY2017604C002).Finally,Thanks for the help of Zu-Hui Li during writing the paper.
文摘n the area of naval architecture and ocean engineering,the research about the underwater xplosion problem is of great significance.To achieve prolonged simulation of near-free surface underwater explosion,the underwater explosion transient numerical model is established in this paper based on compressible Eulerian finite element method(EFEM).Compared with Geers Hunter formula,EFEM is availably validated by simulating the free-field underwater xplosion case.Then,the bubble pulsation and flow field dynamic characteristics of the cases with different underwater explosive depth are compared in this work.Lastly,the height of the water hump and the pressure of flow flied are analyzed quantitatively through the simulation results.
基金This work was funded by the National Natural Science Foundation of China under Grant(Nos.61772152,61502037)the Basic Research Project(Nos.JCKY2016206B001,JCKY2014206C002,JCKY2017604C010)and the Technical Foundation Project(No.JSQB2017206C002).
文摘Underwater target recognition is a key technology for underwater acoustic countermeasure.How to classify and recognize underwater targets according to the noise information of underwater targets has been a hot topic in the field of underwater acoustic signals.In this paper,the deep learning model is applied to underwater target recognition.Improved anti-noise Power-Normalized Cepstral Coefficients(ia-PNCC)is proposed,based on PNCC applied to underwater noises.Multitaper and normalized Gammatone filter banks are applied to improve the anti-noise capacity.The method is combined with a convolutional neural network in order to recognize the underwater target.Experiment results show that the acoustic feature presented by ia-PNCC has lower noise and are wellsuited to underwater target recognition using a convolutional neural network.Compared with the combination of convolutional neural network with single acoustic feature,such as MFCC(Mel-scale Frequency Cepstral Coefficients)or LPCC(Linear Prediction Cepstral Coefficients),the combination of the ia-PNCC with a convolutional neural network offers better accuracy for underwater target recognition.