LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)layered oxides have been regarded as promising alternative cathodes for the next generation of high-energy lithium ion batteries(LIBs)due to high discharge capacities and energy ...LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)layered oxides have been regarded as promising alternative cathodes for the next generation of high-energy lithium ion batteries(LIBs)due to high discharge capacities and energy densities at high operation voltage.However,the capacity fading under high operation voltage still restricts the practical application.Herein,the capacity degradation mechanism of NCM811 at atomic-scale is studied in detail under various cut-off voltages using aberration-corrected scanning transmission electron microscopy(STEM).It is observed that the crystal structure of NCM811 evolution from a layered structure to a rock-salt phase is directly accompanied by serious intergranular cracks under 4.9 V,which is distinguished from the generally accepted structure evolution of layered,disordered layered,defect rock salt and rock salt phases,also observed under 4.3 and 4.7 V.The electron energy loss spectroscopy analysis also confirms the reduction of Ni and Co from the surface to the bulk,not the previously reported only Li/Ni interlayer mixing.The degradation mechanism of NCM811 at a high cut-off voltage of4.9 V is attributed to the formation of intergranular cracks induced by defects,the direct formation of the rock salt phase,and the accompanied reduction of Ni^(2+)and Co^(2+)phases from the surface to the bulk.展开更多
The concept of combining metallic honeycomb with folded thin metallic sheets(corrugation) to construct a novel core type for lightweight sandwich structures is proposed. The honeycomb–corrugation hybrid core is manuf...The concept of combining metallic honeycomb with folded thin metallic sheets(corrugation) to construct a novel core type for lightweight sandwich structures is proposed. The honeycomb–corrugation hybrid core is manufactured by filling the interstices of aluminum corrugations with precision-cut trapezoidal aluminum honeycomb blocks, bonded together using epoxy glue. The performance of such hybrid-cored sandwich panels subjected to out-of-plane compression, transverse shear, and three-point bending is investigated, both experimentally and numerically. The strength and energy absorption of the sandwich are dramatically enhanced, compared to those of a sandwich with either empty corrugation or honeycomb core. The enhancement is induced by the beneficial interaction effects of honeycomb blocks and folded panels on improved buckling resistance as well as altered crushing modes at large plastic deformation.The present approach provides an effective method to further improve the mechanical properties of conventional honeycomb-cored sandwich constructions with low relative densities.展开更多
CdS nanowires-nitrogen doped graphene(CdS NWs-NGR) nanocomposites have been fabricated by an electrostatic self-assembly strategy followed by a hydrothermal reduction. The CdS NWs-NGR exhibits higher photoactivity for...CdS nanowires-nitrogen doped graphene(CdS NWs-NGR) nanocomposites have been fabricated by an electrostatic self-assembly strategy followed by a hydrothermal reduction. The CdS NWs-NGR exhibits higher photoactivity for selective reduction of aromatic nitro organics in water under visible light irradiation than blank CdS nanowires(CdS NWs) and CdS nanowires-reduced graphene oxide(CdS NWs-RGO)nanocomposites. The enhanced photoactivity of CdS NWs-NGR can be attributed to the improved electronic conductivity due to the introduction of nitrogen atoms, which thus enhances the separation and transfer of charge carriers photogenerated from CdS NWs.Our work could provide a facile method to synthesize NGR based one-dimensional(1D) semiconductor composites for selective organic transformations, and broaden the potential applications for NGR as a cocatalyst.展开更多
Cemented paste backill(CPB)is a susta inable mining technology that is widely used in mines and helps to improve the mine environment.To investigate the relationship between aggregate grading and different affecting f...Cemented paste backill(CPB)is a susta inable mining technology that is widely used in mines and helps to improve the mine environment.To investigate the relationship between aggregate grading and different affecting factors and the uniaxial compressive strength(UCS)of the cemented paste backill(CPB),Talbol gradation theory and neural networks is used to evaluate aggregate gradation to determine the optimum aggregate ratio.The mixed aggregate ratio with the least amount of cement(waste stone content river sand content=7:3)is obtained by using Talbol grading theory and pile compactness function and combined with experiments.In addition,the response surface method is used to design strength speaific ratio experiments.The UCS prediction model which ues the ISTM and considers the aggregates gradation have high accuracy.The root mean square error(RMSE)of the prediction results is 0.0914,the coefficient of determination(R^(2))is 0.9973 and the variance account for(VAF)is 99.73.Compared with back propagation neural network(BP-ANN),extreme lea ming machine(ELM)and madal basis function neural network(RBF ANN),LSTM can efectively characterize the nonlinear relationship between UCS and individual affecting factors and predict UCS with high accuracy.The sensitivity analysis of different affecting factors on UCS shows that all 4 factors have significant effect on UCS and sensitivity is in the following ranking:cement content(0.9264)>slurry concentration(0.9179)>aggregate gradation(waste rodk content)(0.9031)>curing time(09031).展开更多
The In segregation and its suppression in InGaAs/AlGaAs quantum well are investigated by using high-resolution x-ray diffraction(XRD)and photoluminescence(PL),combined with the state-of-the-art aberration corrected sc...The In segregation and its suppression in InGaAs/AlGaAs quantum well are investigated by using high-resolution x-ray diffraction(XRD)and photoluminescence(PL),combined with the state-of-the-art aberration corrected scanning transmission electron microscopy(Cs-STEM)techniques.To facility our study,we grow two multiple quantum wells(MQWs)samples,which are almost identical except that in sample B a thin GaAs layer is inserted in each of the InGaAs well and AlGaAs barrier layer comparing to pristine InGaAs/AlGaAs MQWs(sample A).Our study indeed shows the direct evidences that In segregation occurs in the InGaAs/AlGaAs interface,and the effect of the Ga As insertion layer on suppressing the segregation of In atoms is also demonstrated on the atomic-scale.Therefore,the atomic-scale insights are provided to understand the segregation behavior of In atoms and to unravel the underlying mechanism of the effect of GaAs insertion layer on the improvement of crystallinity,interface roughness,and further an enhanced optical performance of InGaAs/AlGaAs QWs.展开更多
The development of solid waste resources as constituent materials for wet shotcrete has significant economic and environmental advantages. In this study, the concept of using tailings as aggregate and fly ash and slag...The development of solid waste resources as constituent materials for wet shotcrete has significant economic and environmental advantages. In this study, the concept of using tailings as aggregate and fly ash and slag powder as auxiliary cementitious material is proposed and experiments are carried out by response surface methodology(RSM). Multivariate nonlinear response models are constructed to investigate the effect of factors on the uniaxial compressive strength(UCS) of tailings wet shotcrete(TWSC). The UCS of TWSC is predicted and optimized by constructing Gaussian process regression(GPR) and genetic algorithm(GA). The UCS of TWSC is gradually enhanced with the increase of slag powder dosage and fineness modulus, and it is enhanced first and then decreased with the increase of fly ash dosage. The microstructure of TWSC has the highest gray value and the highest UCS when the fly ash dosage is about 120 kg·m^(-3). The GPR–GA model constructed in this study achieves high accuracy prediction and optimization of the UCS of TWSC under multi-factor conditions.展开更多
Tailings known as solid waste are generated by the mining industry.The development of tailings as wet shotcrete aggregates has significant economic and environmental benefits.The fine particle size of the tailings res...Tailings known as solid waste are generated by the mining industry.The development of tailings as wet shotcrete aggregates has significant economic and environmental benefits.The fine particle size of the tailings results in a large consumption of traditional cement as a cementitious material and insignificant improvement in strength.Therefore,a composite cementitious system of cement and solid waste resources(fly ash and slag powder)is explored for this study.In this paper,the response surface methodology(RSM)is used to optimize the experimental design and a multivariate nonlinear response model with cement,fly ash and slag powder contents as variables are constructed,which can investigate the effect of the composite cementitious system on the strength of tailing wet shotcrete(TWSC).In addition,the information entropy(IE)is introduced and combined with the RSM to evaluate the composite cementitious system.Finally,the desirability function(DF)combined with RSM is used to optimize the composite cementitious system.The results show that the response model constructed in this paper has R^(2)=0.96 and P-value<0.01(the test result of the model is P-value<0.01),which indicates that the model has high reliability.The higher the content of slag powder and cement in the composite cementitious system,the higher the strength and comprehensive score of the TWSC.There is a critical value of fly ash content,which makes the maximum cementation of the composite cementing system.The optimal mix proportion of the composite cementitious system is obtained based on RSM-DF,which leads to the strength of TWSC at different curing time to achieve the expected index.展开更多
Glioblastoma(GBM)is the most aggressive cancer of the brain and has a high mortality rate due to the lack of effective treatment strategy.Clarification of molecular mechanisms of GBM’s characteristic invasive growth ...Glioblastoma(GBM)is the most aggressive cancer of the brain and has a high mortality rate due to the lack of effective treatment strategy.Clarification of molecular mechanisms of GBM’s characteristic invasive growth is urgently needed to improve the poor prognosis.Single-nuclear sequencing of primary and recurrent GBM samples revealed that levels of M3 muscarinic acetylcholine receptor(CHRM3)were significantly higher in the recurrent samples than in the primary samples.Moreover,immunohistochemical staining of an array of GBM samples showed that high levels of CHRM3 correlated with poor prognosis,consistent with The Cancer Genome Atlas database.Knockdown of CHRM3 inhibited GBM cell growth and invasion.An assay of orthotopic GBM animal model in vivo indicated that inhibition of CHRM3 significantly suppressed GBM progression with prolonged survival time.Transcriptome analysis revealed that CHRM3 knockdown significantly reduced an array of classic factors involved in cancer invasive growth,including MMP1/MMP3/MMP10/MMP12 and CXCL1/CXCL5/CXCL8.Taken together,CHRM3 is a novel and vital factor of GBM progression via regulation of multiple oncogenic genes and may serve as a new biomarker for prognosis and therapy of GBM patients.展开更多
The super-fine particle size of tailings is its drawback as a recycled resource,which is reflected in the low strength of the new construction and industrial materials formed when it is mixed with cement and other cem...The super-fine particle size of tailings is its drawback as a recycled resource,which is reflected in the low strength of the new construction and industrial materials formed when it is mixed with cement and other cementitious materials.Therefore,it is crucial to study the effect of tailings particle size and cementitious material on the strength of tailings wet shotcrete(TWSC)and to investigate the optimal mix proportion.In this paper,a multivariate nonlinear response model was constructed by conducting central composite experiments to investigate the effect of different factors on the strength of TWSC.The strength prediction and mix proportion optimization of TWSC are carried out by machine learning techniques.The results show that the response model has R^(2)>0.94 and P<0.01,which indicates that the model has high reliability.Moreover,the strength of TWSC increases with the increase of tailings fineness modulus and decrease of water-binder ratio,while it also increases and then decreases with the increase of replacement rate of slag powder to cement(SRC rate).The extreme learning machine(ELM)constructed in this paper predicts the strength of TWSC with an accuracy of more than 98%and achieves rapid prediction under multi-factor conditions.It is worth mentioning that the ELM combined with the genetic algorithm(ELM-GA)collaboratively solved to obtain the mix proportion for C15 and C20 strength grades of TWSC and the maximum error is verified by experiments to be less than 2%.展开更多
The development of automation,the Internet of Things(IoT),artificial intelligence(AI),big data,and other digi-tal technologies has made it imperative for pharmaceutical companies to undergo digital transformation to i...The development of automation,the Internet of Things(IoT),artificial intelligence(AI),big data,and other digi-tal technologies has made it imperative for pharmaceutical companies to undergo digital transformation to improve their research and development capabilities,increase the quality of their products,lower operating costs,and gain a competitive edge.One of the most crucial steps in the life-cycle riskman-agement chain for drugs is digital quality assurance(DQA).Based on a literature review,questionnaire survey,and expert consensus,a panel of experts was convened in Shanghai to generate a set of conceptual,pharmaceutical manufacturing-specific DQA specifications.The goal of the consensus is to advance common practices that use digital tools to quickly collect,record,evaluate,and review particular forms of data to enhance the automation of quality assurance and make drug quality activities more efficient.展开更多
BACKGROUND Exosomal miRNAs play crucial roles in many central nervous system diseases.Cerebral small vessel disease(CVSD)is a small vessel disease that is affected by various factors.This study aimed to investigate th...BACKGROUND Exosomal miRNAs play crucial roles in many central nervous system diseases.Cerebral small vessel disease(CVSD)is a small vessel disease that is affected by various factors.This study aimed to investigate the role of exosomal miR-320e in the Wnt/β-catenin pathway stimulated by oxidative stress and assess its clinical correlation with psychiatric symptoms in patients with CVSD.AIM To explore whether exosomal miR-320e could suppress the Wnt/β-catenin pathway and play a protective role in CVSD progression,as well as examine its potential correlation with cognitive impairment and depression in patients with CVSD.METHODS Differentially expressed exosomal miRNAs were filtered by sequencing plasma exosomes from patients with CVSD and healthy controls.Bioinformatics and dual luciferase analyses were used to confirm the binding of miR-320e to Wnt2,and the mRNA and protein levels of downstream components in the Wnt/β-catenin pathway were evaluated when overexpressed or with knockdown of miR-320e under H2O2-induced oxidative stress.In addition,Wnt2-targeting siRNA was used to confirm the role of miR-320e in the Wnt2-mediated inhibition of the Wnt/β-catenin pathway.A retrospective analysis was conducted among patients with CVSD to confirm the correlation between miR-320e expression and the severity of cognitive impairment and depression,which were quantified using the Montreal Cognitive Assessment(MoCA)/Executive Function Assessment(EFA),and the Hamilton Depression Scale(HAMD)/Beck Depression Inventory(BDI),respectively.RESULTS High-throughput sequencing revealed that exosomal miR-320e was downregulated in patients with CVSD.Bioinformatics analysis and dual-luciferase reporter gene experiments showed that exosomal miR-320e inhibited the Wnt/β-catenin pathway in response to oxidative stress by targeting the 3'noncoding region of Wnt2.Uptake of exosomes carrying miR-320e into endothelial cells could also target Wnt2 and inhibit the Wnt2/β-catenin pathway.Elevated miR-320e expression may protect patients with CVSD from relatively severe cognitive impairment and depression,as it was found to have a positive correlation with the MoCA/EFA and HAMD/BDI scores.CONCLUSION Our results suggest that exosomal miR-320e suppresses the Wnt/β-catenin pathway and may play a protective role in CVSD progression.展开更多
BACKGROUND: Transplantation of mesenchymal stem cells(MSCs) has been regarded as a potential treatment for acute liver failure(ALF), but the optimal route was unknown. The present study aimed to explore the most effec...BACKGROUND: Transplantation of mesenchymal stem cells(MSCs) has been regarded as a potential treatment for acute liver failure(ALF), but the optimal route was unknown. The present study aimed to explore the most effective MSCs transplantation route in a swine ALF model.METHODS: The swine ALF model induced by intravenous injection of D-Gal was treated by the transplantation of swine MSCs through four routes including intraportal injection(In P group), hepatic intra-arterial injection(AH group), peripheral intravenous injection(PV group) and intrahepatic injection(IH group). The living conditions and survival time were recorded. Blood samples before and after MSCs transplantation were collected for the analysis of hepatic function. The histology of liver injury was interpreted and scored in terminal samples. Hepatic apoptosis was detected by TUNEL assay. Apoptosis and proliferation related protein expressions including cleaved caspase-3, survivin, AKT, phospho-AKT(Ser473), ERK and phospho-ERK(Tyr204) were analyzed by Western blotting.RESULTS: The average survival time of each group was 10.7 ±1.6 days(In P), 6.0±0.9 days(AH), 4.7±1.4 days(PV), 4.3±0.8 days(IH), respectively, when compared with the average survival time of 3.8±0.8 days in the D-Gal group. The survival rates between the In P group and D-Gal group revealed a statistically significant difference(P<0.01). Pathological and biochemical analysis showed that liver damage was the worst in the D-Gal group, while less injury in the In P group. Histopathological scores revealed a significant decrease in the In P group(3.17±1.04, P<0.01) and AH group(8.17±0.76, P<0.05) as compared with that in the D-Gal group(11.50±1.32). The apoptosis rate in the In P group(25.0%±3.4%, P<0.01) and AH group(40.5%±1.0%, P<0.05) was lower than that in the D-Gal group(70.6%±8.5%). The expression of active caspase-3 was inhibited, while the expression of survivin, AKT, phosphoAKT(Ser473), ERK and phospho-ERK(Tyr204) was elevated in the In P group.CONCLUSIONS: Intraportal injection was superior to other pathways for MSC transplantation. Intraportal MSC transplantation could improve liver function, inhibit apoptosis and prolong the survival time of swine with ALF. The transplanted MSCs may participate in liver regeneration via promoting cell proliferation and suppressing apoptosis during the initial stage of ALF.展开更多
AIM:To investigate the associations of interleukin-17(IL-17)genetic polymorphisms and serum levels with ulcerative colitis(UC)risk.METHODS:Relevant articles were identified through a search of the following electronic...AIM:To investigate the associations of interleukin-17(IL-17)genetic polymorphisms and serum levels with ulcerative colitis(UC)risk.METHODS:Relevant articles were identified through a search of the following electronic databases,excluding language restriction:(1)the Cochrane Library Database(Issue 12,2013);(2)Web of Science(1945-2013);(3)PubMed(1966-2013);(4)CINAHL(1982-2013);(5)EMBASE(1980-2013);and(6)the Chinese Biomedical Database(1982-2013).Meta-analysis was conducted using STATA 12.0 software.Crude odds ratios and standardized mean differences(SMDs)with corresponding95%confidence intervals(CIs)were calculated.All of the included studies met all of the following five criteria:(1)the study design must be a clinical cohort or a case-control study;(2)the study must relate to the relationship between IL-17A/F genetic polymorphismsor serum IL-17 levels and the risk of UC;(3)all patients must meet the diagnostic criteria for UC;(4)the study must provide sufficient information about single nucleotide polymorphism frequencies or serum IL-17 levels;and(5)the genotype distribution of healthy controls must conform to the Hardy-Weinberg equilibrium(HWE).The Newcastle-Ottawa Scale(NOS)criteria were used to assess the methodological quality of the studies.The NOS criteria included three aspects:(1)subject selection:0-4;(2)comparability of subjects:0-2;and(3)clinical outcome:0-3.NOS scores ranged from 0 to 9,with a score≥7 indicating good quality.RESULTS:Of the initial 177 articles,only 16 case-control studies met all of the inclusion criteria.A total of1614 UC patients and 2863 healthy controls were included in this study.Fourteen studies were performed on Asian populations,and two studies on Caucasian populations.Results of the meta-analysis revealed that IL-17A and IL-17F genetic polymorphisms potentially increased UC risk under both allele and dominant models(P<0.001 for all).The results also showed that UC patients had higher serum IL-17 levels than healthy controls(SMD=5.95,95%CI:4.25-7.65,P<0.001).Furthermore,serum IL-17 levels significantly correlated with the severity of UC(moderate vs mild:SMD=2.59,95%CI:0.03-5.16,P<0.05;severe vs mild:SMD=7.09,95%CI:3.96-10.23,P<0.001;severe vs moderate:SMD=5.84,95%CI:5.09-6.59,P<0.001).The NOS score was≥5 for all of the included studies.Based on the sensitivity analysis,no single study influenced the overall pooled estimates.Neither the Begger’s funnel plots nor Egger’s test displayed strong statistical evidence for publication bias(IL-17A/F genetic polymorphisms:t=-2.60,P=0.019;serum IL-17 levels:t=-1.54,P=0.141).CONCLUSION:The findings strongly suggest that IL-17A/F genetic polymorphisms and serum IL-17 levels contribute to the development and progression of UC.展开更多
A novel square honeycomb-cored sandwich beam with perforated bottom facesheet is investigated under threepoint bending,both analytically and numerically.Perforated square holes in the bottom facesheet are characterize...A novel square honeycomb-cored sandwich beam with perforated bottom facesheet is investigated under threepoint bending,both analytically and numerically.Perforated square holes in the bottom facesheet are characterized by the area ratio of the hole to intact facesheet(perforation ratio).While for large-scale engineering applications like the decks of cargo vehicles and transportation ships,the perforations are needed to facilitate the fabrication process(e.g.,laser welding)as well as service maintenance,it is demonstrated that these perforations,when properly designed,can also enhance the resistance of the sandwich to bending.For illustration,fair comparisons among competing sandwich designs having different perforation ratios but equal mass is achieved by systematically thickening the core webs.Further,the perforated sandwich beam is designed with a relatively thick facesheet to avoid local indention failure so that it mainly fails in two competing modes:(1)bending failure,i.e.,yielding of beam cross-section and buckling of top facesheet caused by bending moment;(2)shear failure,i.e.,yielding and buckling of core webs due to shear forcing.The sensitivity of the failure loads to the ratio of core height to beam span is also discussed for varying perforation ratios.As the perfo-ration ratio is increased,the load of shear failure increases due to thickening core webs,while that of bending failure decreases due to the weakening bottom facesheet.Design of a sandwich beam with optimal perforation ratio is realized when the two failure loads are equal,leading to significantly enhanced failure load(up to 60%increase)relative to that of a non-perforated sandwich beam with equal mass.展开更多
Heterosis,which describes the superior vigor and yield of F_1 hybrids with respect to their parents,is observed in many rice hybrid crosses.The exploitation of heterosis is a great leap in the history of rice breeding...Heterosis,which describes the superior vigor and yield of F_1 hybrids with respect to their parents,is observed in many rice hybrid crosses.The exploitation of heterosis is a great leap in the history of rice breeding.With advances in genomics and genetics,high-resolution mapping and functional identification of heterosis-associated loci have been performed in rice.Here we summarize advances in understanding the genetic basis of grain yield heterosis in hybrid rice and provide a vision for the genetic study and breeding application of rice heterosis in the future.展开更多
A comparative optimal design of fluid-saturated prismatic cellular metal honeycombs(PCMHs) having different cell shapes is presented for thermal management applications. Based on the periodic topology of each PCMH, a ...A comparative optimal design of fluid-saturated prismatic cellular metal honeycombs(PCMHs) having different cell shapes is presented for thermal management applications. Based on the periodic topology of each PCMH, a unit cell(UC) for thermal transport analysis was selected to calculate its effective thermal conductivity. Without introducing any empirical coefficient, we modified and extended the analytical model of parallel–series thermal–electric network to a wider porosity range(0.7 ~ 0.98) by considering the effects of two-dimensional local heat conduction in solid ligaments inside each UC. Good agreement was achieved between analytical predictions and numerical simulations based on the method of finite volume. The concept of ligament heat conduction efficiency(LTCE) was proposed to physically explain the mechanisms underlying the effects of ligament configuration on effective thermal conductivity(ETC).Based upon the proposed theory, a construct strategy was developed for designing the ETC by altering the equivalent interaction angle with the direction of heat flow: relatively small average interaction angle for thermal conduction and relatively large one for thermal insulation.展开更多
Porous photocatalysts are promising materials capable of simultaneously adsorbing and oxidizing/reducing target species,showing great potentials in environmental remediation and energy generation.This review offered a...Porous photocatalysts are promising materials capable of simultaneously adsorbing and oxidizing/reducing target species,showing great potentials in environmental remediation and energy generation.This review offered a comprehensive overview of the recent progress in design,fabrication,and applications of porous photocatalysts,including carbon-based semiconductors,metal oxides/sulfides,metal–organic frameworks,and adsorbent–photocatalyst hybrids.The fundamental understanding of the structure–performance relationships of porous materials together with the in-depth insights into the synergetic effects between adsorption and photocatalysis was presented.The strategies to further improve the photocatalytic activity of porous photocatalysts were proposed.This review would provide references and outlooks of constructing efficient porous materials for adsorptive and photocatalytic removal of pollutants and energy production.展开更多
A great deal of oil contaminated the shoreline by the Qingdao oil pipeline explosion in 2013. The four oildegrading consortia were enriched from sediment samples with crude oil as sole carbon and energy sources. The b...A great deal of oil contaminated the shoreline by the Qingdao oil pipeline explosion in 2013. The four oildegrading consortia were enriched from sediment samples with crude oil as sole carbon and energy sources. The biodiversity and community analysis showed that the Luteibacter, Parvibaculum and a genus belonging to Alcanivoracaceae were found predominant bacteria in the four consortia, which belonged to Proteobacteria. Nine strains exhibiting distinct 16S rRNA gene sequences were isolated from the consortia. These strains were identified to eight genera based on 16S rRNA gene sequences. Five of the nine strains degraded more than 30% of the crude oil in two weeks by gravimetric method. From the analysis of GC-MS, most of the isolated strains tended to degrade n-alkanes rather than PAHs. Five strains showed high degrading ability of the total n-alkanes. Only Strain D2 showed great PAHs degrading ability and the degrading rates ranged from 34.9% to 77.5%. The sequencing analysis of the oil-degrading consortia confirmed that the genus of Alcanivorax was one of the dominant bacteria in Consortia A and E and Strain E4 might be one of the dominant bacteria. The strains obtained in this study demonstrated the potential for oil bioremediation in oil-contaminated beach ecosystems.展开更多
基金supported by the National Natural Science Foundation of China(U2032131)the Key R&D Program of Shaanxi Province(2021GY-118)the Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering(2022SX-TD012 and 2021SXTD012)。
文摘LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)layered oxides have been regarded as promising alternative cathodes for the next generation of high-energy lithium ion batteries(LIBs)due to high discharge capacities and energy densities at high operation voltage.However,the capacity fading under high operation voltage still restricts the practical application.Herein,the capacity degradation mechanism of NCM811 at atomic-scale is studied in detail under various cut-off voltages using aberration-corrected scanning transmission electron microscopy(STEM).It is observed that the crystal structure of NCM811 evolution from a layered structure to a rock-salt phase is directly accompanied by serious intergranular cracks under 4.9 V,which is distinguished from the generally accepted structure evolution of layered,disordered layered,defect rock salt and rock salt phases,also observed under 4.3 and 4.7 V.The electron energy loss spectroscopy analysis also confirms the reduction of Ni and Co from the surface to the bulk,not the previously reported only Li/Ni interlayer mixing.The degradation mechanism of NCM811 at a high cut-off voltage of4.9 V is attributed to the formation of intergranular cracks induced by defects,the direct formation of the rock salt phase,and the accompanied reduction of Ni^(2+)and Co^(2+)phases from the surface to the bulk.
基金supported by the National Natural Science Foundation of China(11472208)the National 111 Project of China(B06024)
文摘The concept of combining metallic honeycomb with folded thin metallic sheets(corrugation) to construct a novel core type for lightweight sandwich structures is proposed. The honeycomb–corrugation hybrid core is manufactured by filling the interstices of aluminum corrugations with precision-cut trapezoidal aluminum honeycomb blocks, bonded together using epoxy glue. The performance of such hybrid-cored sandwich panels subjected to out-of-plane compression, transverse shear, and three-point bending is investigated, both experimentally and numerically. The strength and energy absorption of the sandwich are dramatically enhanced, compared to those of a sandwich with either empty corrugation or honeycomb core. The enhancement is induced by the beneficial interaction effects of honeycomb blocks and folded panels on improved buckling resistance as well as altered crushing modes at large plastic deformation.The present approach provides an effective method to further improve the mechanical properties of conventional honeycomb-cored sandwich constructions with low relative densities.
基金supported by the National Natural Science Foundation of China(NSFC)(20903022,20903023,21173045)the Award Program for Minjiang Scholar Professorship+2 种基金the Science and Technology Development of Foundation of Fuzhou University(2009-XQ-10)the Open Fund of Photocatalysis of Fuzhou University(0380038004)the Program for Returned High-Level Overseas Chinese Scholars of Fujian Province
文摘CdS nanowires-nitrogen doped graphene(CdS NWs-NGR) nanocomposites have been fabricated by an electrostatic self-assembly strategy followed by a hydrothermal reduction. The CdS NWs-NGR exhibits higher photoactivity for selective reduction of aromatic nitro organics in water under visible light irradiation than blank CdS nanowires(CdS NWs) and CdS nanowires-reduced graphene oxide(CdS NWs-RGO)nanocomposites. The enhanced photoactivity of CdS NWs-NGR can be attributed to the improved electronic conductivity due to the introduction of nitrogen atoms, which thus enhances the separation and transfer of charge carriers photogenerated from CdS NWs.Our work could provide a facile method to synthesize NGR based one-dimensional(1D) semiconductor composites for selective organic transformations, and broaden the potential applications for NGR as a cocatalyst.
基金This study was supported by the National Key Research and Development Program of China(2018YFC 1900603,2018YFC0604604).
文摘Cemented paste backill(CPB)is a susta inable mining technology that is widely used in mines and helps to improve the mine environment.To investigate the relationship between aggregate grading and different affecting factors and the uniaxial compressive strength(UCS)of the cemented paste backill(CPB),Talbol gradation theory and neural networks is used to evaluate aggregate gradation to determine the optimum aggregate ratio.The mixed aggregate ratio with the least amount of cement(waste stone content river sand content=7:3)is obtained by using Talbol grading theory and pile compactness function and combined with experiments.In addition,the response surface method is used to design strength speaific ratio experiments.The UCS prediction model which ues the ISTM and considers the aggregates gradation have high accuracy.The root mean square error(RMSE)of the prediction results is 0.0914,the coefficient of determination(R^(2))is 0.9973 and the variance account for(VAF)is 99.73.Compared with back propagation neural network(BP-ANN),extreme lea ming machine(ELM)and madal basis function neural network(RBF ANN),LSTM can efectively characterize the nonlinear relationship between UCS and individual affecting factors and predict UCS with high accuracy.The sensitivity analysis of different affecting factors on UCS shows that all 4 factors have significant effect on UCS and sensitivity is in the following ranking:cement content(0.9264)>slurry concentration(0.9179)>aggregate gradation(waste rodk content)(0.9031)>curing time(09031).
基金X.H.gratefully acknowledges the financial support from the National Natural Science Foundation of China(Grant No.21902096)the Scientific Research Foundation of Shaanxi University of Science and Technology(Grant No.126061803)+1 种基金S.M.and B.X.thank the National Natural Science Foundation of China(Grant No.21972103)the Shanxi Provincial Key Innovative Research Team in Science and Technology(Grant No.201703D111026).
文摘The In segregation and its suppression in InGaAs/AlGaAs quantum well are investigated by using high-resolution x-ray diffraction(XRD)and photoluminescence(PL),combined with the state-of-the-art aberration corrected scanning transmission electron microscopy(Cs-STEM)techniques.To facility our study,we grow two multiple quantum wells(MQWs)samples,which are almost identical except that in sample B a thin GaAs layer is inserted in each of the InGaAs well and AlGaAs barrier layer comparing to pristine InGaAs/AlGaAs MQWs(sample A).Our study indeed shows the direct evidences that In segregation occurs in the InGaAs/AlGaAs interface,and the effect of the Ga As insertion layer on suppressing the segregation of In atoms is also demonstrated on the atomic-scale.Therefore,the atomic-scale insights are provided to understand the segregation behavior of In atoms and to unravel the underlying mechanism of the effect of GaAs insertion layer on the improvement of crystallinity,interface roughness,and further an enhanced optical performance of InGaAs/AlGaAs QWs.
基金financially supported by the National Key Research and Development Program of China (Nos.2018YFC1900603 and 2018YFC0604604)。
文摘The development of solid waste resources as constituent materials for wet shotcrete has significant economic and environmental advantages. In this study, the concept of using tailings as aggregate and fly ash and slag powder as auxiliary cementitious material is proposed and experiments are carried out by response surface methodology(RSM). Multivariate nonlinear response models are constructed to investigate the effect of factors on the uniaxial compressive strength(UCS) of tailings wet shotcrete(TWSC). The UCS of TWSC is predicted and optimized by constructing Gaussian process regression(GPR) and genetic algorithm(GA). The UCS of TWSC is gradually enhanced with the increase of slag powder dosage and fineness modulus, and it is enhanced first and then decreased with the increase of fly ash dosage. The microstructure of TWSC has the highest gray value and the highest UCS when the fly ash dosage is about 120 kg·m^(-3). The GPR–GA model constructed in this study achieves high accuracy prediction and optimization of the UCS of TWSC under multi-factor conditions.
基金This work is funded by the National Key Research and Development Program of China(Grant Nos.2018YFC1900603,2018YFC0604604).
文摘Tailings known as solid waste are generated by the mining industry.The development of tailings as wet shotcrete aggregates has significant economic and environmental benefits.The fine particle size of the tailings results in a large consumption of traditional cement as a cementitious material and insignificant improvement in strength.Therefore,a composite cementitious system of cement and solid waste resources(fly ash and slag powder)is explored for this study.In this paper,the response surface methodology(RSM)is used to optimize the experimental design and a multivariate nonlinear response model with cement,fly ash and slag powder contents as variables are constructed,which can investigate the effect of the composite cementitious system on the strength of tailing wet shotcrete(TWSC).In addition,the information entropy(IE)is introduced and combined with the RSM to evaluate the composite cementitious system.Finally,the desirability function(DF)combined with RSM is used to optimize the composite cementitious system.The results show that the response model constructed in this paper has R^(2)=0.96 and P-value<0.01(the test result of the model is P-value<0.01),which indicates that the model has high reliability.The higher the content of slag powder and cement in the composite cementitious system,the higher the strength and comprehensive score of the TWSC.There is a critical value of fly ash content,which makes the maximum cementation of the composite cementing system.The optimal mix proportion of the composite cementitious system is obtained based on RSM-DF,which leads to the strength of TWSC at different curing time to achieve the expected index.
基金supported by Research Fund for Academician Lin He New Medicine(JYHL2021FMS14)Shandong Provincial Natural Science Foundation(ZR2021QH337)PhD Fund of Affiliated Hospital of Jining Medical University(2021-BS-002).
文摘Glioblastoma(GBM)is the most aggressive cancer of the brain and has a high mortality rate due to the lack of effective treatment strategy.Clarification of molecular mechanisms of GBM’s characteristic invasive growth is urgently needed to improve the poor prognosis.Single-nuclear sequencing of primary and recurrent GBM samples revealed that levels of M3 muscarinic acetylcholine receptor(CHRM3)were significantly higher in the recurrent samples than in the primary samples.Moreover,immunohistochemical staining of an array of GBM samples showed that high levels of CHRM3 correlated with poor prognosis,consistent with The Cancer Genome Atlas database.Knockdown of CHRM3 inhibited GBM cell growth and invasion.An assay of orthotopic GBM animal model in vivo indicated that inhibition of CHRM3 significantly suppressed GBM progression with prolonged survival time.Transcriptome analysis revealed that CHRM3 knockdown significantly reduced an array of classic factors involved in cancer invasive growth,including MMP1/MMP3/MMP10/MMP12 and CXCL1/CXCL5/CXCL8.Taken together,CHRM3 is a novel and vital factor of GBM progression via regulation of multiple oncogenic genes and may serve as a new biomarker for prognosis and therapy of GBM patients.
基金funded by the National Key Research and Development Program of China(Grant Nos.2018YFC1900603,2018YFC0604604).
文摘The super-fine particle size of tailings is its drawback as a recycled resource,which is reflected in the low strength of the new construction and industrial materials formed when it is mixed with cement and other cementitious materials.Therefore,it is crucial to study the effect of tailings particle size and cementitious material on the strength of tailings wet shotcrete(TWSC)and to investigate the optimal mix proportion.In this paper,a multivariate nonlinear response model was constructed by conducting central composite experiments to investigate the effect of different factors on the strength of TWSC.The strength prediction and mix proportion optimization of TWSC are carried out by machine learning techniques.The results show that the response model has R^(2)>0.94 and P<0.01,which indicates that the model has high reliability.Moreover,the strength of TWSC increases with the increase of tailings fineness modulus and decrease of water-binder ratio,while it also increases and then decreases with the increase of replacement rate of slag powder to cement(SRC rate).The extreme learning machine(ELM)constructed in this paper predicts the strength of TWSC with an accuracy of more than 98%and achieves rapid prediction under multi-factor conditions.It is worth mentioning that the ELM combined with the genetic algorithm(ELM-GA)collaboratively solved to obtain the mix proportion for C15 and C20 strength grades of TWSC and the maximum error is verified by experiments to be less than 2%.
文摘The development of automation,the Internet of Things(IoT),artificial intelligence(AI),big data,and other digi-tal technologies has made it imperative for pharmaceutical companies to undergo digital transformation to improve their research and development capabilities,increase the quality of their products,lower operating costs,and gain a competitive edge.One of the most crucial steps in the life-cycle riskman-agement chain for drugs is digital quality assurance(DQA).Based on a literature review,questionnaire survey,and expert consensus,a panel of experts was convened in Shanghai to generate a set of conceptual,pharmaceutical manufacturing-specific DQA specifications.The goal of the consensus is to advance common practices that use digital tools to quickly collect,record,evaluate,and review particular forms of data to enhance the automation of quality assurance and make drug quality activities more efficient.
文摘BACKGROUND Exosomal miRNAs play crucial roles in many central nervous system diseases.Cerebral small vessel disease(CVSD)is a small vessel disease that is affected by various factors.This study aimed to investigate the role of exosomal miR-320e in the Wnt/β-catenin pathway stimulated by oxidative stress and assess its clinical correlation with psychiatric symptoms in patients with CVSD.AIM To explore whether exosomal miR-320e could suppress the Wnt/β-catenin pathway and play a protective role in CVSD progression,as well as examine its potential correlation with cognitive impairment and depression in patients with CVSD.METHODS Differentially expressed exosomal miRNAs were filtered by sequencing plasma exosomes from patients with CVSD and healthy controls.Bioinformatics and dual luciferase analyses were used to confirm the binding of miR-320e to Wnt2,and the mRNA and protein levels of downstream components in the Wnt/β-catenin pathway were evaluated when overexpressed or with knockdown of miR-320e under H2O2-induced oxidative stress.In addition,Wnt2-targeting siRNA was used to confirm the role of miR-320e in the Wnt2-mediated inhibition of the Wnt/β-catenin pathway.A retrospective analysis was conducted among patients with CVSD to confirm the correlation between miR-320e expression and the severity of cognitive impairment and depression,which were quantified using the Montreal Cognitive Assessment(MoCA)/Executive Function Assessment(EFA),and the Hamilton Depression Scale(HAMD)/Beck Depression Inventory(BDI),respectively.RESULTS High-throughput sequencing revealed that exosomal miR-320e was downregulated in patients with CVSD.Bioinformatics analysis and dual-luciferase reporter gene experiments showed that exosomal miR-320e inhibited the Wnt/β-catenin pathway in response to oxidative stress by targeting the 3'noncoding region of Wnt2.Uptake of exosomes carrying miR-320e into endothelial cells could also target Wnt2 and inhibit the Wnt2/β-catenin pathway.Elevated miR-320e expression may protect patients with CVSD from relatively severe cognitive impairment and depression,as it was found to have a positive correlation with the MoCA/EFA and HAMD/BDI scores.CONCLUSION Our results suggest that exosomal miR-320e suppresses the Wnt/β-catenin pathway and may play a protective role in CVSD progression.
基金supported by grants from the National Natural Science Foundation of China(81300338)863 National Science and Technology Plans(2013AA020102)Project Funding of Clinical Medical Center of Digestive Disease in Jiangsu Province(BL2012001)
文摘BACKGROUND: Transplantation of mesenchymal stem cells(MSCs) has been regarded as a potential treatment for acute liver failure(ALF), but the optimal route was unknown. The present study aimed to explore the most effective MSCs transplantation route in a swine ALF model.METHODS: The swine ALF model induced by intravenous injection of D-Gal was treated by the transplantation of swine MSCs through four routes including intraportal injection(In P group), hepatic intra-arterial injection(AH group), peripheral intravenous injection(PV group) and intrahepatic injection(IH group). The living conditions and survival time were recorded. Blood samples before and after MSCs transplantation were collected for the analysis of hepatic function. The histology of liver injury was interpreted and scored in terminal samples. Hepatic apoptosis was detected by TUNEL assay. Apoptosis and proliferation related protein expressions including cleaved caspase-3, survivin, AKT, phospho-AKT(Ser473), ERK and phospho-ERK(Tyr204) were analyzed by Western blotting.RESULTS: The average survival time of each group was 10.7 ±1.6 days(In P), 6.0±0.9 days(AH), 4.7±1.4 days(PV), 4.3±0.8 days(IH), respectively, when compared with the average survival time of 3.8±0.8 days in the D-Gal group. The survival rates between the In P group and D-Gal group revealed a statistically significant difference(P<0.01). Pathological and biochemical analysis showed that liver damage was the worst in the D-Gal group, while less injury in the In P group. Histopathological scores revealed a significant decrease in the In P group(3.17±1.04, P<0.01) and AH group(8.17±0.76, P<0.05) as compared with that in the D-Gal group(11.50±1.32). The apoptosis rate in the In P group(25.0%±3.4%, P<0.01) and AH group(40.5%±1.0%, P<0.05) was lower than that in the D-Gal group(70.6%±8.5%). The expression of active caspase-3 was inhibited, while the expression of survivin, AKT, phosphoAKT(Ser473), ERK and phospho-ERK(Tyr204) was elevated in the In P group.CONCLUSIONS: Intraportal injection was superior to other pathways for MSC transplantation. Intraportal MSC transplantation could improve liver function, inhibit apoptosis and prolong the survival time of swine with ALF. The transplanted MSCs may participate in liver regeneration via promoting cell proliferation and suppressing apoptosis during the initial stage of ALF.
文摘AIM:To investigate the associations of interleukin-17(IL-17)genetic polymorphisms and serum levels with ulcerative colitis(UC)risk.METHODS:Relevant articles were identified through a search of the following electronic databases,excluding language restriction:(1)the Cochrane Library Database(Issue 12,2013);(2)Web of Science(1945-2013);(3)PubMed(1966-2013);(4)CINAHL(1982-2013);(5)EMBASE(1980-2013);and(6)the Chinese Biomedical Database(1982-2013).Meta-analysis was conducted using STATA 12.0 software.Crude odds ratios and standardized mean differences(SMDs)with corresponding95%confidence intervals(CIs)were calculated.All of the included studies met all of the following five criteria:(1)the study design must be a clinical cohort or a case-control study;(2)the study must relate to the relationship between IL-17A/F genetic polymorphismsor serum IL-17 levels and the risk of UC;(3)all patients must meet the diagnostic criteria for UC;(4)the study must provide sufficient information about single nucleotide polymorphism frequencies or serum IL-17 levels;and(5)the genotype distribution of healthy controls must conform to the Hardy-Weinberg equilibrium(HWE).The Newcastle-Ottawa Scale(NOS)criteria were used to assess the methodological quality of the studies.The NOS criteria included three aspects:(1)subject selection:0-4;(2)comparability of subjects:0-2;and(3)clinical outcome:0-3.NOS scores ranged from 0 to 9,with a score≥7 indicating good quality.RESULTS:Of the initial 177 articles,only 16 case-control studies met all of the inclusion criteria.A total of1614 UC patients and 2863 healthy controls were included in this study.Fourteen studies were performed on Asian populations,and two studies on Caucasian populations.Results of the meta-analysis revealed that IL-17A and IL-17F genetic polymorphisms potentially increased UC risk under both allele and dominant models(P<0.001 for all).The results also showed that UC patients had higher serum IL-17 levels than healthy controls(SMD=5.95,95%CI:4.25-7.65,P<0.001).Furthermore,serum IL-17 levels significantly correlated with the severity of UC(moderate vs mild:SMD=2.59,95%CI:0.03-5.16,P<0.05;severe vs mild:SMD=7.09,95%CI:3.96-10.23,P<0.001;severe vs moderate:SMD=5.84,95%CI:5.09-6.59,P<0.001).The NOS score was≥5 for all of the included studies.Based on the sensitivity analysis,no single study influenced the overall pooled estimates.Neither the Begger’s funnel plots nor Egger’s test displayed strong statistical evidence for publication bias(IL-17A/F genetic polymorphisms:t=-2.60,P=0.019;serum IL-17 levels:t=-1.54,P=0.141).CONCLUSION:The findings strongly suggest that IL-17A/F genetic polymorphisms and serum IL-17 levels contribute to the development and progression of UC.
基金supported by the National Natural Science Foundation of China (Grants 11472209, 11472208)the China Postdoctoral Science Foundation (Grant 2016M600782)+2 种基金the Postdoctoral Scientific Research Project of Shaanxi Province (Grant 2016BSHYDZZ18)the Fundamental Research Funds for Xi’an Jiaotong University (Grant xjj2015102)the Jiangsu Province Key Laboratory of High-end Structural Materials (Grant hsm1305)
文摘A novel square honeycomb-cored sandwich beam with perforated bottom facesheet is investigated under threepoint bending,both analytically and numerically.Perforated square holes in the bottom facesheet are characterized by the area ratio of the hole to intact facesheet(perforation ratio).While for large-scale engineering applications like the decks of cargo vehicles and transportation ships,the perforations are needed to facilitate the fabrication process(e.g.,laser welding)as well as service maintenance,it is demonstrated that these perforations,when properly designed,can also enhance the resistance of the sandwich to bending.For illustration,fair comparisons among competing sandwich designs having different perforation ratios but equal mass is achieved by systematically thickening the core webs.Further,the perforated sandwich beam is designed with a relatively thick facesheet to avoid local indention failure so that it mainly fails in two competing modes:(1)bending failure,i.e.,yielding of beam cross-section and buckling of top facesheet caused by bending moment;(2)shear failure,i.e.,yielding and buckling of core webs due to shear forcing.The sensitivity of the failure loads to the ratio of core height to beam span is also discussed for varying perforation ratios.As the perfo-ration ratio is increased,the load of shear failure increases due to thickening core webs,while that of bending failure decreases due to the weakening bottom facesheet.Design of a sandwich beam with optimal perforation ratio is realized when the two failure loads are equal,leading to significantly enhanced failure load(up to 60%increase)relative to that of a non-perforated sandwich beam with equal mass.
基金funded by the National Key Research and Development Program of China(2016YFD0100902)。
文摘Heterosis,which describes the superior vigor and yield of F_1 hybrids with respect to their parents,is observed in many rice hybrid crosses.The exploitation of heterosis is a great leap in the history of rice breeding.With advances in genomics and genetics,high-resolution mapping and functional identification of heterosis-associated loci have been performed in rice.Here we summarize advances in understanding the genetic basis of grain yield heterosis in hybrid rice and provide a vision for the genetic study and breeding application of rice heterosis in the future.
基金supported by the National Natural Science Foundation of China(51506160,11472208,11472209)China Post-Doctoral Science Foundation Project(2015M580845)+1 种基金the Fundamental Research Funds for Xi’an Jiaotong University(xjj2015102)the Beijing Key Lab of Heating,Gas Supply,Ventilating and Air Conditioning Engineering(NR2016K01)
文摘A comparative optimal design of fluid-saturated prismatic cellular metal honeycombs(PCMHs) having different cell shapes is presented for thermal management applications. Based on the periodic topology of each PCMH, a unit cell(UC) for thermal transport analysis was selected to calculate its effective thermal conductivity. Without introducing any empirical coefficient, we modified and extended the analytical model of parallel–series thermal–electric network to a wider porosity range(0.7 ~ 0.98) by considering the effects of two-dimensional local heat conduction in solid ligaments inside each UC. Good agreement was achieved between analytical predictions and numerical simulations based on the method of finite volume. The concept of ligament heat conduction efficiency(LTCE) was proposed to physically explain the mechanisms underlying the effects of ligament configuration on effective thermal conductivity(ETC).Based upon the proposed theory, a construct strategy was developed for designing the ETC by altering the equivalent interaction angle with the direction of heat flow: relatively small average interaction angle for thermal conduction and relatively large one for thermal insulation.
基金financially supported by the National Natural Science Foundation of China(21706224,21671075)the China Postdoctoral Science Foundation(2020M672810)+3 种基金the Science and Technology Innovation Commission of Shenzhen Municipality(JCYJ20180307123906004 and JCYJ20190808181003717)the Research Grants Council of Hong Kong(CityU 21301817,11215518)the Strategic Research Grants from City University of Hong Kong(Ref:CityU 11306419 and 11308420)the Applied Research Grant from City University of Hong Kong(Ref:CityU 9667217)。
文摘Porous photocatalysts are promising materials capable of simultaneously adsorbing and oxidizing/reducing target species,showing great potentials in environmental remediation and energy generation.This review offered a comprehensive overview of the recent progress in design,fabrication,and applications of porous photocatalysts,including carbon-based semiconductors,metal oxides/sulfides,metal–organic frameworks,and adsorbent–photocatalyst hybrids.The fundamental understanding of the structure–performance relationships of porous materials together with the in-depth insights into the synergetic effects between adsorption and photocatalysis was presented.The strategies to further improve the photocatalytic activity of porous photocatalysts were proposed.This review would provide references and outlooks of constructing efficient porous materials for adsorptive and photocatalytic removal of pollutants and energy production.
基金The National Natural Science Foundation of China under contract Nos 41406127 and 41476103the Basic Scientific Fund for National Public Research Institutes of China under contract No.2015T05+2 种基金the National Natural Science Foundation of ChinaShandong Joint Funded Project under contract No.U1406403the Marine Science and Technology Project of Huangdao District under contract No.2014-4-20the 2012 Taishan Scholar Award and China-ASEAN Maritime Cooperation Fund East Asia Marine Cooperation Platform
文摘A great deal of oil contaminated the shoreline by the Qingdao oil pipeline explosion in 2013. The four oildegrading consortia were enriched from sediment samples with crude oil as sole carbon and energy sources. The biodiversity and community analysis showed that the Luteibacter, Parvibaculum and a genus belonging to Alcanivoracaceae were found predominant bacteria in the four consortia, which belonged to Proteobacteria. Nine strains exhibiting distinct 16S rRNA gene sequences were isolated from the consortia. These strains were identified to eight genera based on 16S rRNA gene sequences. Five of the nine strains degraded more than 30% of the crude oil in two weeks by gravimetric method. From the analysis of GC-MS, most of the isolated strains tended to degrade n-alkanes rather than PAHs. Five strains showed high degrading ability of the total n-alkanes. Only Strain D2 showed great PAHs degrading ability and the degrading rates ranged from 34.9% to 77.5%. The sequencing analysis of the oil-degrading consortia confirmed that the genus of Alcanivorax was one of the dominant bacteria in Consortia A and E and Strain E4 might be one of the dominant bacteria. The strains obtained in this study demonstrated the potential for oil bioremediation in oil-contaminated beach ecosystems.
