The traditional standard wet sieving method uses steel sieves with aperture?0.063 mm and can only determine the particle size distribution(PSD)of gravel and sand in general soil.This paper extends the traditional meth...The traditional standard wet sieving method uses steel sieves with aperture?0.063 mm and can only determine the particle size distribution(PSD)of gravel and sand in general soil.This paper extends the traditional method and presents an extended wet sieving method.The extended method uses both the steel sieves and the nylon filter cloth sieves.The apertures of the cloth sieves are smaller than 0.063 mm and equal 0.048 mm,0.038 mm,0.014 mm,0.012 mm,0.0063 mm,0.004 mm,0.003 mm,0.002 mm,and 0.001 mm,respectively.The extended method uses five steps to separate the general soil into many material sub-groups of gravel,sand,silt and clay with known particle size ranges.The complete PSD of the general soil is then calculated from the dry masses of the individual material sub-groups.The extended method is demonstrated with a general soil of completely decomposed granite(CDG)in Hong Kong,China.The silt and clay materials with different particle size ranges are further examined,checked and verified using stereomicroscopic observation,physical and chemical property tests.The results further confirm the correctness of the extended wet sieving method.展开更多
Background:Glioma is a kind of tumor that easily deteriorates and originates from glial cells in nerve tissue.Honokiol is a bisphenol compound that is an essential monomeric compound extracted from the roots and bark ...Background:Glioma is a kind of tumor that easily deteriorates and originates from glial cells in nerve tissue.Honokiol is a bisphenol compound that is an essential monomeric compound extracted from the roots and bark of Magnoliaceae plants.It also has anti-infection,antitumor,and immunomodulatory effects.In this study,we found that honokiol induces cell apoptosis in the human glioma cell lines U87-MG and U251-MG.However,the mechanism through which honokiol regulates glioma cell apoptosis is still unknown.Methods:We performed RNA-seq analysis of U251-MG cells treated with honokiol and control cells.Protein-protein interaction(PPI)network analysis was performed,and the 10 top hub unigenes were examined via real-time quantitative PCR.Furthermore,MAPK signaling and ferroptosis were detected via western blotting.Results:332 differentially expressed genes(DEGs)were found,comprising 163 increased and 169 decreased genes.Analysis of the DEGs revealed that various biological processes were enriched,including‘response to hypoxia’,‘cerebellum development cellular response to hypoxia,’‘iron ion binding,’‘oxygen transporter activity,’‘oxygen binding,’‘ferric iron binding,’and‘structural constituent of cytoskeleton.’Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis revealed that the DEGs were enriched in the following pathways:‘mitogen-activated protein kinases(MAPK)’,‘Hypoxia-inducible factor 1(HIF-1)’,‘ferroptosis,’‘Peroxisome proliferator-activated receptor(PPAR),’‘Phosphatidylinositol-4,5-bisphosphate 3-kinase(PI3K)-protein kinase B(Akt),’and‘phagosome.’Among these pathways,the MAPK signaling pathway and ferroptosis were verified.Conclusion:This study revealed the potential mechanism by which honokiol induces apoptosis and provided a comprehensive analysis of DEGs in honokiol-treated U251-MG cells and the associated signaling pathways.These data could lead to new ideas for future research and therapy for patients with glioma.展开更多
As industrialization and informatization becomemore deeply intertwined,industrial control networks have entered an era of intelligence.The connection between industrial control networks and the external internet is be...As industrialization and informatization becomemore deeply intertwined,industrial control networks have entered an era of intelligence.The connection between industrial control networks and the external internet is becoming increasingly close,which leads to frequent security accidents.This paper proposes a model for the industrial control network.It includes a malware containment strategy that integrates intrusion detection,quarantine,and monitoring.Basedonthismodel,the role of keynodes in the spreadofmalware is studied,a comparisonexperiment is conducted to validate the impact of the containment strategy.In addition,the dynamic behavior of the model is analyzed,the basic reproduction number is computed,and the disease-free and endemic equilibrium of the model is also obtained by the basic reproduction number.Moreover,through simulation experiments,the effectiveness of the containment strategy is validated,the influence of the relevant parameters is analyzed,and the containment strategy is optimized.In otherwords,selective immunity to key nodes can effectively suppress the spread ofmalware andmaintain the stability of industrial control systems.The earlier the immunization of key nodes,the better.Once the time exceeds the threshold,immunizing key nodes is almost ineffective.The analysis provides a better way to contain the malware in the industrial control network.展开更多
Morphology of hydraulic fracture surface has significant effects on oil and gas flow,proppant migration and fracture closure,which plays an important role in oil and gas fracturing stimulation.In this paper,we analyze...Morphology of hydraulic fracture surface has significant effects on oil and gas flow,proppant migration and fracture closure,which plays an important role in oil and gas fracturing stimulation.In this paper,we analyzed the fracture surface characteristics induced by supercritical carbon dioxide(SC-CO_(2))and water in open-hole and perforation completion conditions under triaxial stresses.A simple calculation method was proposed to quantitatively analyze the fracture surface area and roughness in macro-level based on three-dimensional(3D)scanning data.In micro-level,scanning electron micrograph(SEM)was used to analyze the features of fracture surface.The results showed that the surface area of the induced fracture increases with perforation angle for both SC-CO_(2)and water fracturing,and the surface area of SC-CO_(2)-induced fracture is 6.49%e58.57%larger than that of water-induced fracture.The fractal dimension and surface roughness of water-induced fractures increase with the increase in perforation angle,while those of SC-CO_(2)-induced fractures decrease with the increasing perforation angle.A considerable number of microcracks and particle peeling pits can be observed on SC-CO_(2)-induced fracture surface while there are more flat particle surfaces in water-induced fracture surface through SEM images,indicating that fractures tend to propagate along the boundary of the particle for SC-CO_(2)fracturing while water-induced fractures prefer to cut through particles.These findings are of great significance for analyzing fracture mechanism and evaluating fracturing stimulation performance.展开更多
There is an increasing demand for rechargeable batteries in high-performance energy storage systems.The current dominating Li-ion batteries are limited by price,resource availability,as well as their theoretical capac...There is an increasing demand for rechargeable batteries in high-performance energy storage systems.The current dominating Li-ion batteries are limited by price,resource availability,as well as their theoretical capacities.So that the community has started to explore alternative battery chemistries.As a promising multivalent battery type,rechargeable magnesium batteries(RMBs)have attracted increasing attention because of high safety,high volumetric energy density,and low cost thanks to abundant resource of Mg.However,the development of high-performance anodes is still hampered by formation of passivating layers on the Mg surface.Additionally,dendrites can also grow under certain conditions with pure Mg anodes,which requires further studies for reliable operation window and substitutes.Therefore,this review specifically aims to provide an overview on the often overlooked yet very important anode materials of RMBs,with the hope to inspire more attention and research efforts for the achievement of over-all better performance of future RMBs.c 2020 Published by Elsevier B.V.on behalf of Chongqing University.展开更多
Catalytic CO_(2)conversion has witnessed a dynamic growth in recent decades.Various materials have been applied to reduce CO_(2)into fuels and value-added chemicals.Normally,the powder-based catalysts cannot be direct...Catalytic CO_(2)conversion has witnessed a dynamic growth in recent decades.Various materials have been applied to reduce CO_(2)into fuels and value-added chemicals.Normally,the powder-based catalysts cannot be directly utilized for CO_(2)conversion.Much attention was paid to the study of catalytic membranes in order to overcome this issue,since it is convenient for catalytic membranes to be employed in devices for practical applications.In this review,the recent research development of porous catalytic membranes for CO_(2)conversion is summarized.The preparations of representative porous catalytic membranes and their CO_(2)conversion methods,including electrocatalysis,photocatalysis,photoelectrocatalysis,thermalcatalysis and biocatalysis,are discussed in detail.This review is expected to provide deep understanding on the utilization of porous catalytic membranes for CO_(2)conversion.展开更多
Semiconductor nanomaterial-based epitaxial heterostructures with precisely controlled compositions and morphologies are of great importance for various applications in optoelectronics,thermoelectrics,and catalysis.Unt...Semiconductor nanomaterial-based epitaxial heterostructures with precisely controlled compositions and morphologies are of great importance for various applications in optoelectronics,thermoelectrics,and catalysis.Until now,various kinds of epitaxial heterostructures have been constructed.In this minireview,we will first introduce the synthesis of semiconductor nanomaterial-based epitaxial heterostructures by wet-chemical methods.Various architectures based on different kinds of seeds or templates are illustrated,and their growth mechanisms are discussed in detail.Then,the applications of epitaxial heterostructures in optoelectronics,catalysis,and thermoelectrics are described.Finally,we provide some challenges and personal perspectives for the future research directions of semiconductor nanomaterial-based epitaxial heterostructures.展开更多
Manganese fluoride(MnF2)is a high-performance lithium-ion battery anode material with an excellent structural stability,low synthesis cost,and better manufacturing convenience.However,its low theoretical capacity(577 ...Manganese fluoride(MnF2)is a high-performance lithium-ion battery anode material with an excellent structural stability,low synthesis cost,and better manufacturing convenience.However,its low theoretical capacity(577 mAh g^(-1)),weak conductivity of fluoride,and poor recyclability limit its practical application.Fortunately,oxygen vacancies(Ov)and heteroatomic doping are among the most promising strategies to modulate the inherent reduced electronic conductivity and kinetic response of electrode materials in order to boost their lithium storage capacity.Herein,self-templating,self-optimizing,and self-supporting metal-organic framework template approach with the introduction of oxygen vacancies by substitution of exogenous heteroatoms is proposed,where triple heteroatom-doped(N,O,and F)carbon-encapsulated MOF-derived manganese fluoride(Ov-ZMF@NOFs)microstructures are designed.Interestingly,the exogenously introduced triple heteroatomic carbon matrix forms a fluffy three-dimensional mechanical structure,interlaced conducting networks,efficient conducting pathways,and intense electrochemical dynamics at the periphery of the manganese fluoride nanoparticles.Benefiting from the above-mentioned features,the Ov-ZMF@NOFs exhibit expected electrochemical properties with ultra-long recyclability(high reversible capacity of 419 mAh g^(-1)at 6 A g^(-1))and good rate performance(capacity of 232 mAh g^(-1)at a current density of 16 A g^(-1)).Theoretical calculations underline the essential contribution of multiple heteroatoms doping in boosting the electrode conductivity and reducing the lithium-ion migration energy barrier.Combining controllable vacancy engineering and heteroatom doping technology at the nanoscale provides a new philosophy and concept for the design and fabrication of next-generation high-energy lithium-ion battery materials.展开更多
Soybean agglutinin(SBA)is an important anti-nutritional factor in soybean.SBA can induce animal growth inhibition,cause pathological changes of intestinal tissue,and decrease in the immune system functioning.Recently,...Soybean agglutinin(SBA)is an important anti-nutritional factor in soybean.SBA can induce animal growth inhibition,cause pathological changes of intestinal tissue,and decrease in the immune system functioning.Recently,a great deal of research has been done on the effects of SBA on cell morphology,division,apoptosis,autophagy,as well as the correlated signal transduction pathway.This review mainly covers the chemical and biological characteristics of SBA,describes the multifaceted aspects of SBA anti-nutritional functions,and highlights the possible cellular and molecular mechanism of anti-nutritional effects of SBA.This review has important implications for the prevention and treatment of SBA-induced diseases,drug development,processing techniques of plant products,prevention of food-borne toxins,as well as human and animal health protection.展开更多
[Objectives] To compare content of proanthocyanidins and polysaccharides in wild Lycium ruthenicum. [Methods] The wild L. ruthenicum collected from different regions such as Qinghai, Inner Mongolia, Ningxia and Gansu ...[Objectives] To compare content of proanthocyanidins and polysaccharides in wild Lycium ruthenicum. [Methods] The wild L. ruthenicum collected from different regions such as Qinghai, Inner Mongolia, Ningxia and Gansu Province were taken as the research objects. The conventional indicators such as proanthocyanidins and polysaccharides of the experimental materials were determined, and the proanthocyanidins and polysaccharides of the experimental materials in different regions were compared and analyzed. The difference in content and correlation, and the cluster analysis method were used to divide clusters of the experimental materials. [Results] The absorbance of proanthocyanidins in the fruit of wild L. ruthenicum was No.4>No.1>No.5>No.6>No.3>No.2, among which the absorbance of anthocyanin(2.43) of wild L. ruthenicum variety No.4 was significantly higher than other experimental materials(P<0.05), and proanthocyanidin of No.2 had the lowest absorbance value of 1.35. There was no significant difference between No.3 and No.6(P>0.05), and there were significant differences among other experimental materials(P<0.05). The content of polysaccharides was: No.3>No.7>No.2>No.4>No.5>No.6>No.1; there was no significant difference between No.3 and No.7(P>0.05), but significantly higher than other materials(P<0.05). Besides, proanthocyanidins and polysaccharides showed significant variability, but there was no consistency in the correlation between them. [Conclusions] In terms of the absorbance of proanthocyanidins, the experimental materials No.1 and No.4 can be classified into a cluster; experimental materials No.2, No.3, No.5 and No.6 can be classified into another cluster. This can provide a theoretical basis for the introduction and breeding of fine varieties.展开更多
It becomes increasingly clear that non-uniform distribution of immiscible fluids in porous rock is particularly relevant to seismic wave dispersion. White proposed a patchy saturation model in 1975, in which spherical...It becomes increasingly clear that non-uniform distribution of immiscible fluids in porous rock is particularly relevant to seismic wave dispersion. White proposed a patchy saturation model in 1975, in which spherical gas pockets were located at the center of a liquid saturated cube. For an extremely light and compressible inner gas, the physical properties can be approximated by a vacuum with White's model. The model successfully analyzes the dispersion phenomena of a P-wave velocity in gas-water- saturated rocks. In the case of liquid pocket saturation, e.g., an oil-pocket surrounded by a water saturated host matrix, the light fluid-pocket assumption is doubtful, and few works have been reported in White's framework. In this work, Poisson's ratio, the bulk modulus, and the effective density of a dual-liquid saturated medium are formulated for the heterogeneous porous rocks containing liquid-pockets. The analysis of the difference between the newly derived bulk modulus and that of White's model shows that the effects of liquid-pocket saturation do not disappear unless the porosity approaches zero. The inner pocket fluid can no longer be ignored. The improvements of the P-wave velocity predictions are illustrated with two examples taken from experiments, i.e., the P-wave velocity in the sandstone saturated by oil and brine and the P-wave velocity for heavy oils and stones at different temperatures.展开更多
A preliminary miRNA screening showed that expression levels of rno-miRNA-27a-3p were significantly increased in the serum and brain tissues of rats undergoing cerebral ischemia.In recent years,there is evidence of the...A preliminary miRNA screening showed that expression levels of rno-miRNA-27a-3p were significantly increased in the serum and brain tissues of rats undergoing cerebral ischemia.In recent years,there is evidence of the protective capacity of the saponins extracted from panax ginseng and its primary active ingredient ginsenosideRg1oncerebral ischemic injury.Methods:Fetal rat neurons(FRNs)were cultured in glucose-and-serumfree medium and exposed to hypoxia to establish a cerebral ischemia model in vitro(oxygen and glucose deprivation model,OGD).Antioxidant indexes(CAT,SOD),inflammatory markers(MPO,TNF-αand IL-6),and the expression of apoptosis and proliferation associated proteins(NF kB-p65,Caspase 3-cleaved,BCL-2)were examined.Results:Pre-treatment of Rg1(30–100μg/mL)could effectively inhibit the decline of antioxidant indexes(CAT,SOD)and increase in inflammatory markers(MPO,TNF-αand IL-6),and effectively inhibited the apoptosis in FRNs induced by OGD in a gradient-dependent manner.The mechanism analysis showed that the role of Rg1 in protecting against ischemia-induced neuron damage depends on its indirect up-regulation of PPAR protein via suppression of rnomiRNA-27a-3p.Moreover,these effects of Rg1 could be reversed by exogenous rno-miRNA-27a-3p and PPAR gene silencing in FRNs exposed to OGD.Conclusion:To summarize,our study demonstrates that Rg1 could effectively attenuate neuronal damage caused by cerebral ischemia via the rno-miRNA-27a-3p/PPARγpathway.Further,clarification of the novel mechanism will certainly improve our previous understanding of the role of Rg1 and enhancing its level in treatments for alleviating ischemic brain injury.展开更多
Water resources are one of the key factors restricting the development of arid areas,and cloud water resources is an important part of water resources.The arid region of central Asia is the core region of the current ...Water resources are one of the key factors restricting the development of arid areas,and cloud water resources is an important part of water resources.The arid region of central Asia is the core region of the current national green silk road construction,and is the largest arid region in the world.Based on cloud cover data of ECMWF,the current study analyzed temporal and spatial characteristics of cloud properties in arid regions of Central Asia between 1980 and 2019.Our findings show that:(1)From the point of view of spatial distribution,total cloudiness in arid regions of Central Asia was low in the south and high in the north.The distribution of high cloud frequency and medium cloud frequency was higher in the south and lower in the north,while low cloud frequency distribution was low in the south and high in the north.(2)In terms of time,the variation of cloud cover and cloud type frequency had obvious seasonal characteristics.From winter to spring,cloud cover increased,and the change of cloud type frequency increased.From spring to summer,cloud cover continued to increase and the change of cloud type frequency increased further.Cloud cover began to decrease from summer to autumn,and the change of cloud type frequency also decreased.(3)Generally,average total cloud cover decreased in most of central Asia,and high and medium cloud cover increased while low cloud cover decreased.This study provides a reference for the rational development of cloud resources in the region.展开更多
Apigenin (4’, 5, 7-trihydroxyflavone, AP), a dietary flavonoid, is reported to have several therapeutic effects in different diseases including cancer. In the present study, in order to explore the potential mechanis...Apigenin (4’, 5, 7-trihydroxyflavone, AP), a dietary flavonoid, is reported to have several therapeutic effects in different diseases including cancer. In the present study, in order to explore the potential mechanism and provide the references for further studies, we investigated the effect of apigenin at various dosages on the hepatic oxidative stress of male rats. Totally 48 SD male rats were randomly divided into control group (saline, 1 ml/100g·bw), low-dose group (AP, 234 mg/kg·bw), middle-dose group (AP, 468 mg/kg·bw) and high-dose group (AP, 936 mg/kg·bw). The rats were administered with apigenin or saline via intragastriation once a day, 6 days per week, and 5 consecutive weeks. Rats were sacrificed and the livers were harvested and then immediately preserved at ﹣20°C. Liver homogenate was prepared before detection. Hepatic malondialdehyde (MDA), nitric oxide syntheses (NOS), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC) and glutathione (GSH) were determined by colorimetric methods according to the provided procedures. The weights of liver and spleen in apigenin treatment groups did not reveal statistically significant difference when compared with that in the control group (P > 0.05). Total protein (TP), albumin (ALB) and globulin (GLO) in apigenin treatment groups were significantly lower than those in the control group (P < 0.05). SOD in the middle-dose group (AP, 468 mg/kg·bw) and high-dose group (AP, 936 mg/kg·bw) were significantly higher than that in the control group (P < 0.05). T-AOC, CAT and GSH-Px in apigenin treatment groups were significantly lower than those in the control group (P < 0.05). In high-dose AP group (AP, 936 mg/kg·bw), apigenin can result in the reduction of T-AOC, thus leading to the oxidative damage of liver tissues. In contrast, in middle-dose AP group (AP, 468 mg/kg·bw), apegenin can reduce the elimination capacity of oxygen free radicals.展开更多
As a superior alternative to sutures,tissue adhesives have been developed significantly in recent years.However,existing tissue adhesives struggle to form fast and stable adhesion between tissue interfaces,bond weakly...As a superior alternative to sutures,tissue adhesives have been developed significantly in recent years.However,existing tissue adhesives struggle to form fast and stable adhesion between tissue interfaces,bond weakly in wet environments and lack bioactivity.In this study,a degradable and bioactive citrate-based polyurethane adhesive is constructed to achieve rapid and strong tissue adhesion.The hydrophobic layer was created with polycaprolactone to overcome the bonding failure between tissue and adhesion layer in wet environments,which can effectively improve the wet bonding strength.This citrate-based polyurethane adhesive provides rapid,non-invasive,liquid-tight and seamless closure of skin incisions,overcoming the limitations of sutures and commercial tissue adhesives.In addition,it exhibits biocompatibility,biodegradability and hemostatic properties.The degradation product citrate could promote the process of angiogenesis and accelerate wound healing.This study provides a novel approach to the development of a fast-adhering wet tissue adhesive and provides a valuable contribution to the development of polyurethane-based tissue adhesives.展开更多
Diazocines,a type of photoswitch molecules,are distinguished by their unique conformation and photochromic properties.Molecular engineering of diazocines,especially theπ-extended ones,remains challenging due to limit...Diazocines,a type of photoswitch molecules,are distinguished by their unique conformation and photochromic properties.Molecular engineering of diazocines,especially theπ-extended ones,remains challenging due to limited synthetic methods.Here,we developed threeπ-fused diazocines(BAZO-1,BAZO-2,and BAZO-3)via Bischler–Napieralski cyclization.Their isomerizations(Z⇆E)were switchable under visible light sources(427 and 630 nm).The size of theirπ-extension exerted a significant influence on the isomerization process,whereby the biggest fourfold ring-closure diazocine(BAZO-3)showed the fastest conversion rate(Z→E).Notably,the half-life(t1/2)of the E isomer of BAZO-3 was 14.6 times higher than that of the twofold ring-closure BAZO-1.Thus,BAZO-3 acted as a molecular tweezer based on double N-embedded pyrene units,allowing it to bind to pyrene through supramolecular interactions.This work may pave the way for designing novel photoswitches with long half-lives and lightcontrolled properties.展开更多
基金The work described in this paper was partially supported by grants from the Research Grant Council of the Hong Kong Special Administrative Region,China(Project Nos.HKU 17207518 and R5037-18).
文摘The traditional standard wet sieving method uses steel sieves with aperture?0.063 mm and can only determine the particle size distribution(PSD)of gravel and sand in general soil.This paper extends the traditional method and presents an extended wet sieving method.The extended method uses both the steel sieves and the nylon filter cloth sieves.The apertures of the cloth sieves are smaller than 0.063 mm and equal 0.048 mm,0.038 mm,0.014 mm,0.012 mm,0.0063 mm,0.004 mm,0.003 mm,0.002 mm,and 0.001 mm,respectively.The extended method uses five steps to separate the general soil into many material sub-groups of gravel,sand,silt and clay with known particle size ranges.The complete PSD of the general soil is then calculated from the dry masses of the individual material sub-groups.The extended method is demonstrated with a general soil of completely decomposed granite(CDG)in Hong Kong,China.The silt and clay materials with different particle size ranges are further examined,checked and verified using stereomicroscopic observation,physical and chemical property tests.The results further confirm the correctness of the extended wet sieving method.
基金The study was supported by the Natural Science Foundation of Jilin Province(Grant No.20200201444JC).
文摘Background:Glioma is a kind of tumor that easily deteriorates and originates from glial cells in nerve tissue.Honokiol is a bisphenol compound that is an essential monomeric compound extracted from the roots and bark of Magnoliaceae plants.It also has anti-infection,antitumor,and immunomodulatory effects.In this study,we found that honokiol induces cell apoptosis in the human glioma cell lines U87-MG and U251-MG.However,the mechanism through which honokiol regulates glioma cell apoptosis is still unknown.Methods:We performed RNA-seq analysis of U251-MG cells treated with honokiol and control cells.Protein-protein interaction(PPI)network analysis was performed,and the 10 top hub unigenes were examined via real-time quantitative PCR.Furthermore,MAPK signaling and ferroptosis were detected via western blotting.Results:332 differentially expressed genes(DEGs)were found,comprising 163 increased and 169 decreased genes.Analysis of the DEGs revealed that various biological processes were enriched,including‘response to hypoxia’,‘cerebellum development cellular response to hypoxia,’‘iron ion binding,’‘oxygen transporter activity,’‘oxygen binding,’‘ferric iron binding,’and‘structural constituent of cytoskeleton.’Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis revealed that the DEGs were enriched in the following pathways:‘mitogen-activated protein kinases(MAPK)’,‘Hypoxia-inducible factor 1(HIF-1)’,‘ferroptosis,’‘Peroxisome proliferator-activated receptor(PPAR),’‘Phosphatidylinositol-4,5-bisphosphate 3-kinase(PI3K)-protein kinase B(Akt),’and‘phagosome.’Among these pathways,the MAPK signaling pathway and ferroptosis were verified.Conclusion:This study revealed the potential mechanism by which honokiol induces apoptosis and provided a comprehensive analysis of DEGs in honokiol-treated U251-MG cells and the associated signaling pathways.These data could lead to new ideas for future research and therapy for patients with glioma.
基金Scientific Research Project of Liaoning Province Education Department,Code:LJKQZ20222457&LJKMZ20220781Liaoning Province Nature Fund Project,Code:No.2022-MS-291.
文摘As industrialization and informatization becomemore deeply intertwined,industrial control networks have entered an era of intelligence.The connection between industrial control networks and the external internet is becoming increasingly close,which leads to frequent security accidents.This paper proposes a model for the industrial control network.It includes a malware containment strategy that integrates intrusion detection,quarantine,and monitoring.Basedonthismodel,the role of keynodes in the spreadofmalware is studied,a comparisonexperiment is conducted to validate the impact of the containment strategy.In addition,the dynamic behavior of the model is analyzed,the basic reproduction number is computed,and the disease-free and endemic equilibrium of the model is also obtained by the basic reproduction number.Moreover,through simulation experiments,the effectiveness of the containment strategy is validated,the influence of the relevant parameters is analyzed,and the containment strategy is optimized.In otherwords,selective immunity to key nodes can effectively suppress the spread ofmalware andmaintain the stability of industrial control systems.The earlier the immunization of key nodes,the better.Once the time exceeds the threshold,immunizing key nodes is almost ineffective.The analysis provides a better way to contain the malware in the industrial control network.
基金National Natural Science Foundation of China(Grant No.51804318)the China Postdoctoral Science Foundation Founded Project(Grant No.2019M650963)National Key Basic Research and Development Program of China(Grant No.2014CB239203).
文摘Morphology of hydraulic fracture surface has significant effects on oil and gas flow,proppant migration and fracture closure,which plays an important role in oil and gas fracturing stimulation.In this paper,we analyzed the fracture surface characteristics induced by supercritical carbon dioxide(SC-CO_(2))and water in open-hole and perforation completion conditions under triaxial stresses.A simple calculation method was proposed to quantitatively analyze the fracture surface area and roughness in macro-level based on three-dimensional(3D)scanning data.In micro-level,scanning electron micrograph(SEM)was used to analyze the features of fracture surface.The results showed that the surface area of the induced fracture increases with perforation angle for both SC-CO_(2)and water fracturing,and the surface area of SC-CO_(2)-induced fracture is 6.49%e58.57%larger than that of water-induced fracture.The fractal dimension and surface roughness of water-induced fractures increase with the increase in perforation angle,while those of SC-CO_(2)-induced fractures decrease with the increasing perforation angle.A considerable number of microcracks and particle peeling pits can be observed on SC-CO_(2)-induced fracture surface while there are more flat particle surfaces in water-induced fracture surface through SEM images,indicating that fractures tend to propagate along the boundary of the particle for SC-CO_(2)fracturing while water-induced fractures prefer to cut through particles.These findings are of great significance for analyzing fracture mechanism and evaluating fracturing stimulation performance.
基金the German Research Foundation DFG project(LI 2839/1-1)National Natural Science Foundation of China(51971044)MF acknowledges funding from EU research and innovation framework programme via ttE-MAGIC,project(ID:824066)。
文摘There is an increasing demand for rechargeable batteries in high-performance energy storage systems.The current dominating Li-ion batteries are limited by price,resource availability,as well as their theoretical capacities.So that the community has started to explore alternative battery chemistries.As a promising multivalent battery type,rechargeable magnesium batteries(RMBs)have attracted increasing attention because of high safety,high volumetric energy density,and low cost thanks to abundant resource of Mg.However,the development of high-performance anodes is still hampered by formation of passivating layers on the Mg surface.Additionally,dendrites can also grow under certain conditions with pure Mg anodes,which requires further studies for reliable operation window and substitutes.Therefore,this review specifically aims to provide an overview on the often overlooked yet very important anode materials of RMBs,with the hope to inspire more attention and research efforts for the achievement of over-all better performance of future RMBs.c 2020 Published by Elsevier B.V.on behalf of Chongqing University.
基金supported by the Ministry of Education Singapore under the Academic Research Funds(RT12/19 and MOE-MOET2EP10120-0003)the Singapore National Research Foundation Investigatorship(NRF-NRFI2018-03)。
文摘Catalytic CO_(2)conversion has witnessed a dynamic growth in recent decades.Various materials have been applied to reduce CO_(2)into fuels and value-added chemicals.Normally,the powder-based catalysts cannot be directly utilized for CO_(2)conversion.Much attention was paid to the study of catalytic membranes in order to overcome this issue,since it is convenient for catalytic membranes to be employed in devices for practical applications.In this review,the recent research development of porous catalytic membranes for CO_(2)conversion is summarized.The preparations of representative porous catalytic membranes and their CO_(2)conversion methods,including electrocatalysis,photocatalysis,photoelectrocatalysis,thermalcatalysis and biocatalysis,are discussed in detail.This review is expected to provide deep understanding on the utilization of porous catalytic membranes for CO_(2)conversion.
基金supported by MOE under AcRF Tier 2(ARC 19/15,No.MOE2014-T2-2-093,MOE2015T2-2-057,MOE2016-T2-2-103,MOE2017-T2-1-162)and AcRF Tier 1(2016-T1-001-147,2016-T1-002-051,2017-T1001-150,2017-T1-002-119)NTU under Start-Up Grant(M4081296.070.500000)in Singapore.
文摘Semiconductor nanomaterial-based epitaxial heterostructures with precisely controlled compositions and morphologies are of great importance for various applications in optoelectronics,thermoelectrics,and catalysis.Until now,various kinds of epitaxial heterostructures have been constructed.In this minireview,we will first introduce the synthesis of semiconductor nanomaterial-based epitaxial heterostructures by wet-chemical methods.Various architectures based on different kinds of seeds or templates are illustrated,and their growth mechanisms are discussed in detail.Then,the applications of epitaxial heterostructures in optoelectronics,catalysis,and thermoelectrics are described.Finally,we provide some challenges and personal perspectives for the future research directions of semiconductor nanomaterial-based epitaxial heterostructures.
基金support from Guangzhou Science and Technology Project,China(no.201904010213)Special Funds for the Cultivation of Guangdong College Students'Scientific and Technological Innovation(“Climbing Program”Special Funds,pdjh2021a0129).
文摘Manganese fluoride(MnF2)is a high-performance lithium-ion battery anode material with an excellent structural stability,low synthesis cost,and better manufacturing convenience.However,its low theoretical capacity(577 mAh g^(-1)),weak conductivity of fluoride,and poor recyclability limit its practical application.Fortunately,oxygen vacancies(Ov)and heteroatomic doping are among the most promising strategies to modulate the inherent reduced electronic conductivity and kinetic response of electrode materials in order to boost their lithium storage capacity.Herein,self-templating,self-optimizing,and self-supporting metal-organic framework template approach with the introduction of oxygen vacancies by substitution of exogenous heteroatoms is proposed,where triple heteroatom-doped(N,O,and F)carbon-encapsulated MOF-derived manganese fluoride(Ov-ZMF@NOFs)microstructures are designed.Interestingly,the exogenously introduced triple heteroatomic carbon matrix forms a fluffy three-dimensional mechanical structure,interlaced conducting networks,efficient conducting pathways,and intense electrochemical dynamics at the periphery of the manganese fluoride nanoparticles.Benefiting from the above-mentioned features,the Ov-ZMF@NOFs exhibit expected electrochemical properties with ultra-long recyclability(high reversible capacity of 419 mAh g^(-1)at 6 A g^(-1))and good rate performance(capacity of 232 mAh g^(-1)at a current density of 16 A g^(-1)).Theoretical calculations underline the essential contribution of multiple heteroatoms doping in boosting the electrode conductivity and reducing the lithium-ion migration energy barrier.Combining controllable vacancy engineering and heteroatom doping technology at the nanoscale provides a new philosophy and concept for the design and fabrication of next-generation high-energy lithium-ion battery materials.
基金supported by the National NaturalScienceFoundationofChina(No.31802093)Fund Project of Jilin Agricultural University(2019019).
文摘Soybean agglutinin(SBA)is an important anti-nutritional factor in soybean.SBA can induce animal growth inhibition,cause pathological changes of intestinal tissue,and decrease in the immune system functioning.Recently,a great deal of research has been done on the effects of SBA on cell morphology,division,apoptosis,autophagy,as well as the correlated signal transduction pathway.This review mainly covers the chemical and biological characteristics of SBA,describes the multifaceted aspects of SBA anti-nutritional functions,and highlights the possible cellular and molecular mechanism of anti-nutritional effects of SBA.This review has important implications for the prevention and treatment of SBA-induced diseases,drug development,processing techniques of plant products,prevention of food-borne toxins,as well as human and animal health protection.
基金Supported by Science and Technology Program of Inner Mongolia(201602083)Special Fund for Scientific Research of Inner Mongolia Agricultural University"Special Program for Breeding(Selection)of Animal and Plant Varieties"(YZGC2017023)
文摘[Objectives] To compare content of proanthocyanidins and polysaccharides in wild Lycium ruthenicum. [Methods] The wild L. ruthenicum collected from different regions such as Qinghai, Inner Mongolia, Ningxia and Gansu Province were taken as the research objects. The conventional indicators such as proanthocyanidins and polysaccharides of the experimental materials were determined, and the proanthocyanidins and polysaccharides of the experimental materials in different regions were compared and analyzed. The difference in content and correlation, and the cluster analysis method were used to divide clusters of the experimental materials. [Results] The absorbance of proanthocyanidins in the fruit of wild L. ruthenicum was No.4>No.1>No.5>No.6>No.3>No.2, among which the absorbance of anthocyanin(2.43) of wild L. ruthenicum variety No.4 was significantly higher than other experimental materials(P<0.05), and proanthocyanidin of No.2 had the lowest absorbance value of 1.35. There was no significant difference between No.3 and No.6(P>0.05), and there were significant differences among other experimental materials(P<0.05). The content of polysaccharides was: No.3>No.7>No.2>No.4>No.5>No.6>No.1; there was no significant difference between No.3 and No.7(P>0.05), but significantly higher than other materials(P<0.05). Besides, proanthocyanidins and polysaccharides showed significant variability, but there was no consistency in the correlation between them. [Conclusions] In terms of the absorbance of proanthocyanidins, the experimental materials No.1 and No.4 can be classified into a cluster; experimental materials No.2, No.3, No.5 and No.6 can be classified into another cluster. This can provide a theoretical basis for the introduction and breeding of fine varieties.
基金Project supported by the Open Foundation of SINOPEC Key Laboratory of Geophysics(No.WTYJY-WX2013-04-02)the National Key Basic Research Program of China(973 Program)(No.2014CB239006)the 12th 5-Year Basic Research Program of China National Packaging Corporation(CNPC)(No.2014A-3611)
文摘It becomes increasingly clear that non-uniform distribution of immiscible fluids in porous rock is particularly relevant to seismic wave dispersion. White proposed a patchy saturation model in 1975, in which spherical gas pockets were located at the center of a liquid saturated cube. For an extremely light and compressible inner gas, the physical properties can be approximated by a vacuum with White's model. The model successfully analyzes the dispersion phenomena of a P-wave velocity in gas-water- saturated rocks. In the case of liquid pocket saturation, e.g., an oil-pocket surrounded by a water saturated host matrix, the light fluid-pocket assumption is doubtful, and few works have been reported in White's framework. In this work, Poisson's ratio, the bulk modulus, and the effective density of a dual-liquid saturated medium are formulated for the heterogeneous porous rocks containing liquid-pockets. The analysis of the difference between the newly derived bulk modulus and that of White's model shows that the effects of liquid-pocket saturation do not disappear unless the porosity approaches zero. The inner pocket fluid can no longer be ignored. The improvements of the P-wave velocity predictions are illustrated with two examples taken from experiments, i.e., the P-wave velocity in the sandstone saturated by oil and brine and the P-wave velocity for heavy oils and stones at different temperatures.
基金supported by the National Natural Science Foundation of China,Nos.81973317,81374007,81870977the Natural Science Foundation of Heilongjiang Province,HL2019H062+1 种基金the Projects of Basic Scientific Research Business Expenses in Higher Education Institutions of Heilongjiang Province,No.2018-KYYWF-MY-005the Students Innovative and the Entrepreneurship Training Scientific Research Foundation of Heilongjiang Province,No.102292017001.
文摘A preliminary miRNA screening showed that expression levels of rno-miRNA-27a-3p were significantly increased in the serum and brain tissues of rats undergoing cerebral ischemia.In recent years,there is evidence of the protective capacity of the saponins extracted from panax ginseng and its primary active ingredient ginsenosideRg1oncerebral ischemic injury.Methods:Fetal rat neurons(FRNs)were cultured in glucose-and-serumfree medium and exposed to hypoxia to establish a cerebral ischemia model in vitro(oxygen and glucose deprivation model,OGD).Antioxidant indexes(CAT,SOD),inflammatory markers(MPO,TNF-αand IL-6),and the expression of apoptosis and proliferation associated proteins(NF kB-p65,Caspase 3-cleaved,BCL-2)were examined.Results:Pre-treatment of Rg1(30–100μg/mL)could effectively inhibit the decline of antioxidant indexes(CAT,SOD)and increase in inflammatory markers(MPO,TNF-αand IL-6),and effectively inhibited the apoptosis in FRNs induced by OGD in a gradient-dependent manner.The mechanism analysis showed that the role of Rg1 in protecting against ischemia-induced neuron damage depends on its indirect up-regulation of PPAR protein via suppression of rnomiRNA-27a-3p.Moreover,these effects of Rg1 could be reversed by exogenous rno-miRNA-27a-3p and PPAR gene silencing in FRNs exposed to OGD.Conclusion:To summarize,our study demonstrates that Rg1 could effectively attenuate neuronal damage caused by cerebral ischemia via the rno-miRNA-27a-3p/PPARγpathway.Further,clarification of the novel mechanism will certainly improve our previous understanding of the role of Rg1 and enhancing its level in treatments for alleviating ischemic brain injury.
基金financially supported by the National Natural Science Foundation of China (41867030, 41971036)the National Natural Science Foundation innovation research group science foundation of China (41421061)
文摘Water resources are one of the key factors restricting the development of arid areas,and cloud water resources is an important part of water resources.The arid region of central Asia is the core region of the current national green silk road construction,and is the largest arid region in the world.Based on cloud cover data of ECMWF,the current study analyzed temporal and spatial characteristics of cloud properties in arid regions of Central Asia between 1980 and 2019.Our findings show that:(1)From the point of view of spatial distribution,total cloudiness in arid regions of Central Asia was low in the south and high in the north.The distribution of high cloud frequency and medium cloud frequency was higher in the south and lower in the north,while low cloud frequency distribution was low in the south and high in the north.(2)In terms of time,the variation of cloud cover and cloud type frequency had obvious seasonal characteristics.From winter to spring,cloud cover increased,and the change of cloud type frequency increased.From spring to summer,cloud cover continued to increase and the change of cloud type frequency increased further.Cloud cover began to decrease from summer to autumn,and the change of cloud type frequency also decreased.(3)Generally,average total cloud cover decreased in most of central Asia,and high and medium cloud cover increased while low cloud cover decreased.This study provides a reference for the rational development of cloud resources in the region.
文摘Apigenin (4’, 5, 7-trihydroxyflavone, AP), a dietary flavonoid, is reported to have several therapeutic effects in different diseases including cancer. In the present study, in order to explore the potential mechanism and provide the references for further studies, we investigated the effect of apigenin at various dosages on the hepatic oxidative stress of male rats. Totally 48 SD male rats were randomly divided into control group (saline, 1 ml/100g·bw), low-dose group (AP, 234 mg/kg·bw), middle-dose group (AP, 468 mg/kg·bw) and high-dose group (AP, 936 mg/kg·bw). The rats were administered with apigenin or saline via intragastriation once a day, 6 days per week, and 5 consecutive weeks. Rats were sacrificed and the livers were harvested and then immediately preserved at ﹣20°C. Liver homogenate was prepared before detection. Hepatic malondialdehyde (MDA), nitric oxide syntheses (NOS), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC) and glutathione (GSH) were determined by colorimetric methods according to the provided procedures. The weights of liver and spleen in apigenin treatment groups did not reveal statistically significant difference when compared with that in the control group (P > 0.05). Total protein (TP), albumin (ALB) and globulin (GLO) in apigenin treatment groups were significantly lower than those in the control group (P < 0.05). SOD in the middle-dose group (AP, 468 mg/kg·bw) and high-dose group (AP, 936 mg/kg·bw) were significantly higher than that in the control group (P < 0.05). T-AOC, CAT and GSH-Px in apigenin treatment groups were significantly lower than those in the control group (P < 0.05). In high-dose AP group (AP, 936 mg/kg·bw), apigenin can result in the reduction of T-AOC, thus leading to the oxidative damage of liver tissues. In contrast, in middle-dose AP group (AP, 468 mg/kg·bw), apegenin can reduce the elimination capacity of oxygen free radicals.
基金supported by grants from the National Natural Science Foundation of China(52372272,32201109,32360234)the Key Basic Research Program of Shenzhen(JCYJ20200109150218836)+1 种基金the Guangdong Basic and Applied Basic Research Foundation(2022B1515120052,2021A1515110557)the Self-innovation Research Funding Project of Hanjiang Laboratory(HJL202202A002).
文摘As a superior alternative to sutures,tissue adhesives have been developed significantly in recent years.However,existing tissue adhesives struggle to form fast and stable adhesion between tissue interfaces,bond weakly in wet environments and lack bioactivity.In this study,a degradable and bioactive citrate-based polyurethane adhesive is constructed to achieve rapid and strong tissue adhesion.The hydrophobic layer was created with polycaprolactone to overcome the bonding failure between tissue and adhesion layer in wet environments,which can effectively improve the wet bonding strength.This citrate-based polyurethane adhesive provides rapid,non-invasive,liquid-tight and seamless closure of skin incisions,overcoming the limitations of sutures and commercial tissue adhesives.In addition,it exhibits biocompatibility,biodegradability and hemostatic properties.The degradation product citrate could promote the process of angiogenesis and accelerate wound healing.This study provides a novel approach to the development of a fast-adhering wet tissue adhesive and provides a valuable contribution to the development of polyurethane-based tissue adhesives.
基金supported financially by the Singapore Agency for Science,Technology,and Research(A*STAR)under its Manufacturing,Trade and Connectivity Individual Research Grant(IRG,grant no.M22K2c0077)National Natural Science Foundation of China(NSFC,grant no.21975178).
文摘Diazocines,a type of photoswitch molecules,are distinguished by their unique conformation and photochromic properties.Molecular engineering of diazocines,especially theπ-extended ones,remains challenging due to limited synthetic methods.Here,we developed threeπ-fused diazocines(BAZO-1,BAZO-2,and BAZO-3)via Bischler–Napieralski cyclization.Their isomerizations(Z⇆E)were switchable under visible light sources(427 and 630 nm).The size of theirπ-extension exerted a significant influence on the isomerization process,whereby the biggest fourfold ring-closure diazocine(BAZO-3)showed the fastest conversion rate(Z→E).Notably,the half-life(t1/2)of the E isomer of BAZO-3 was 14.6 times higher than that of the twofold ring-closure BAZO-1.Thus,BAZO-3 acted as a molecular tweezer based on double N-embedded pyrene units,allowing it to bind to pyrene through supramolecular interactions.This work may pave the way for designing novel photoswitches with long half-lives and lightcontrolled properties.