Studying the relationship between rhizosphere microorganisms and root exudates is of great significance for the interaction between rhizosphere microorganisms and plants, and the prevention and control of soil-borne d...Studying the relationship between rhizosphere microorganisms and root exudates is of great significance for the interaction between rhizosphere microorganisms and plants, and the prevention and control of soil-borne diseases. This article analyzed the effects of different microorganisms on tobacco root exudates and rhizosphere microorganisms. It was found that the bacterial wilt pathogen can greatly increase acids and amines, while the probiotic <i>B. amyloliquefaciens</i> ZM9 can eliminate some acids and amines. The results of the study show that the root exudates of pathogenic bacteria may contain a variety of allelochemicals that cause soil-borne diseases.展开更多
OBJECTIVE:To observe the curative effect of an acupoint application with a Dingqi analgesic patch on moderate to severe pain caused by liver cancer.METHODS:Forty patients with moderate to severe pain caused by liver c...OBJECTIVE:To observe the curative effect of an acupoint application with a Dingqi analgesic patch on moderate to severe pain caused by liver cancer.METHODS:Forty patients with moderate to severe pain caused by liver cancer were randomly divided intoatreatmentgroup(TG)andacontrolgroup(CG).Patients with moderate pain were given 100 mg qd of a sustainably released tablet of tramadol hydrochloride;patientswithseverepainweregiven4.2mg q3d of the fentanyl transdermal system.The ashi points Ganshu(BL 18),Danshu(BL 19) and Qimen(LR 14) were chosen for the acupoint application intervention.CG patients were given a sham patch and TG patients were given a Dingqi analgesic patch.A visual analogue scale(VAS) was used before treatment and after 1,3,6,9 and 12 days of treatment.The Karnofsky score was measured before treatment and after 12 days of treatment.Any main adverse reactions(e.g.nausea,constipation,dizziness and headache) were recorded after 6 and 12 days of treatment.Any skin side effects(i.e.skin irritation and allergic reactions) were recorded.RESULTS:The VAS in TG was significantly lower than that in CG after 3,6,9 and 12 days of treatment(P<0.05).There was no significant difference in the Karnofsky score before treatment and after 12 days of treatment between CG and TG.There were also no significant differences in the main adverse reactions or skin side effects after 6 and 12 days of treatment between CG andTG(P>0.05).CONCLUSION:The Dingqi analgesic patch can enhance the analgesic effect of tramadol and fentanyl.展开更多
The consensus of the automotive industry and traffic management authorities is that autonomous vehicles must follow the same traffic laws as human drivers.Using formal or digital methods,natural language traffic rules...The consensus of the automotive industry and traffic management authorities is that autonomous vehicles must follow the same traffic laws as human drivers.Using formal or digital methods,natural language traffic rules can be translated into machine language and used by autonomous vehicles.In this paper,a translation flow is designed.Beyond the translation,a deeper examination is required,because the semantics of natural languages are rich and complex,and frequently contain hidden assumptions.The issue of how to ensure that digital rules are accurate and consistent with the original intent of the traffic rules they represent is both significant and unresolved.In response,we propose a method of formal verification that combines equivalence verification with model checking.Reasonable and reassuring digital traffic rules can be obtained by utilizing the proposed traffic rule digitization flow and verification method.In addition,we offer a number of simulation applications that employ digital traffic rules to assess vehicle violations.The experimental findings indicate that our digital rules utilizing metric temporal logic(MTL)can be easily incorporated into simulation platforms and autonomous driving systems(ADS).展开更多
Objective：Rabies is invariably a fatal encephalomyelitis that is considered to be a serious public health problem.It is necessary to develop standard rabies virus diagnostic tools,especially for diagnosing the strain...Objective：Rabies is invariably a fatal encephalomyelitis that is considered to be a serious public health problem.It is necessary to develop standard rabies virus diagnostic tools,especially for diagnosing the strains prevalent in China.Methods：Monoclonal antibodies（MAbs）specific to rabies virus were produced and characterized by enzyme linked immunosorbent assay（ELISA）,isotyping,affinity assay,immunofluorescence assay（IFA）,and immunocytochemistry.The MAb,whose affinity was higher for antigen,was used to establish an antigen captureELISA（AC-ELISA）detection system and test the efficiency by using clinical samples.Results：The heavy chain subclasses of two MAbs were all determined to be IgG2a.The 3C7 MAb showed stronger reactivity with rabies virus protein than the 2C5 MAb in an ELISA analysis,whereas the 3C7 MAb showed the highest affinity for antigen.IFA and immunocytochemistry results also indicated that the two MAbs could recognize rabies virus protein in its native form in cell samples.Data obtained using clinical samples showed that rabies virus could be detected by AC-ELISA detection system using the 3C7 MAb.Conclusion：It was potentially useful for the further development of highly sensitive,easily handled,and relatively rapid detection kits/tools for rabies surveillance in those areas where rabies is endemic,especially in China.展开更多
In this study,the PH13-8Mo stainless steel parts doped without and with cerium(Ce)were fabricated via laser powder bed fusion followed by post-heat treatment,and systematically compared in terms of microstructure,phas...In this study,the PH13-8Mo stainless steel parts doped without and with cerium(Ce)were fabricated via laser powder bed fusion followed by post-heat treatment,and systematically compared in terms of microstructure,phase constituent,and tensile properties.The comparative results show that doping Ce-modified grains with the equiaxed morphology and finer size,increased the mechanical stability of austenite,and enhanced the sphericity of oxide inclusion in the resultant PH13-8Mo.Additionally,the coherency between the newly-formed CeAlO 3 inclusion and matrix was effectively im proved after doping Ce,as compared to the original aluminum oxide inclusion without doping Ce.The resultant PH13-8Mo parts doped with Ce yielded an ultimate tensile strength of 1446±20 MPa with a fracture elongation of 16.0%±1.5%,for the first time meeting the AMS 5629E H1000 standard for the PH13-8Mo made by additive manufacturing(AM).The enhanced strength results from the strengthening effects of nanoscale precipitation(inclusion)and grain refining.Meanwhile,the ductilizing mechanism can be attributed to the enhanced inclusion sphericity and ameliorative coherency between the inclusion and matrix,and improved misorientation angle of grain boundary owing to the modification by Ce,which efficiently re-duced the stress concentration and enhanced cracking resistance during deformation.Therefore,doping rare earth elements presents a promising pathway to synergistically improve the strength and ductility of stainless steels by AM.展开更多
Although chimeric antigen receptor-modified(CAR)T cell therapy has been successfully applied in the treatment of acute B lymphocytic leukemia,its effect on Burkitt lymphoma(BL)and chronic B lymphocytic leukemia(B-CLL)...Although chimeric antigen receptor-modified(CAR)T cell therapy has been successfully applied in the treatment of acute B lymphocytic leukemia,its effect on Burkitt lymphoma(BL)and chronic B lymphocytic leukemia(B-CLL)is unsatisfactory.Moreover,fatal side effects greatly impede CAR T cell application.Extracellular vesicles(EVs)are excellent carriers of therapeutic agents.Nevertheless,EVs mainly accumulate in the liver when administered without modification.As an envelope glycoprotein of Epstein–Barr viruses,gp350 can efficiently bind CD21 on B cells.Here,gp350 was directly anchored onto red blood cell EVs(RBC-EVs)via its transmembrane region combined with low-voltage electroporation.The results showed that gp350 could anchor to RBC-EVs with high efficiency and that the resulting gp350-anchored RBC-EVs(RBC-EVs/gp350^(Etp))exhibited increased targeting to CD21+BL and B-CLL relative to RBC-EVs.After the loading of doxorubicin or fludarabine,RBC-EVs/gp350^(Etp) had powerful cytotoxicity and therapeutic efficacy on CD21+BL or B-CLL,respectively.Moreover,RBC-EVs/gp350^(Etp) loaded with a drug did not exhibit any apparent systemic toxicity and specifically induced the apoptosis of tumor B cells but not normal Bcells.Therefore,our findings indicate that drug-loaded RBC-EVs/gp350^(Etp) may be adopted in the treatment of CD21+B cell malignancies.展开更多
In order to improve the spore yield of compound Bacillus spp. (B. amyloliquefaciens, B. laterosporus and B. megaterium), the effects of nutrient conditions including carbon source, nitrogen source, mineral salt and fe...In order to improve the spore yield of compound Bacillus spp. (B. amyloliquefaciens, B. laterosporus and B. megaterium), the effects of nutrient conditions including carbon source, nitrogen source, mineral salt and fermentation conditions including the inoculum age, inoculation amount, loading volume of liquid and initial pH on the spore yield were studied. The results indicated that the optimized medium was glucoses 20 g/L, soybean meal 30.0 g/L, K2HPO4 1.0 g/L;fermentation temperature is 37℃, the inoculum age 12 h, initial pH 7.0, 2% inoculation amount, loading volume of liquid 20 mL/250 mL. Under the optimized conditions of culture medium and fermentation for compound Bacillus spp., spore yield was 10.24 times more than the initial medium, and the spore formation rate reached more than 90%.展开更多
The research on relationship between rhizosphere microbes and root exudates has a great significance on discussion of interaction between rhizosphere microbes and plants, as well as control of soil-borne diseases and ...The research on relationship between rhizosphere microbes and root exudates has a great significance on discussion of interaction between rhizosphere microbes and plants, as well as control of soil-borne diseases and insect pest. GC-MS was used to analyze changes of tobacco root exudates under the antagonistic action of tobacco bacterial wilt and black shank. It turned out that when pathogens of tobacco bacterial wilt and black shank in tobacco root microorganisms increase, tobacco root exudates augmented rapidly among of which organic acids have the biggest growth, followed by amines. When the pathogens of tobacco bacterial wilt and black shank are inhibited by the active substance of antagonistic antibacterial, 20 - 23 kinds of root exudates are added;besides, the content of 7 substances was reduced to 0. Another inter-esting finding was that the fluctuations of phthalic acid, isophthalic acid and benzoic acid, which have caused continuous cropping obstacles, were very dis-tinct. The results of this study have provided novel clues for the exploration of continuous tobacco cropping obstacles and soil-borne diseases.展开更多
O-phthalic acid is a kind of important pollutant, which accumulates in the environment with the extensive use of plastics and other products. Meanwhile, phthalic acid is one of the high content of allelopathic autotox...O-phthalic acid is a kind of important pollutant, which accumulates in the environment with the extensive use of plastics and other products. Meanwhile, phthalic acid is one of the high content of allelopathic autotoxic substances secreted by tobacco. The accumulation of phthalic acid in soil is an important cause of tobacco continuous cropping effect. In order to degrade phthalic acid accumulated in environment, the barrier effect of tobacco continuous cropping caused by phthalic acid accumulation in soil can be removed. A strain capable of degrading phthalic acid was isolated from sludge of sewage treatment plant and compared with 16 s DNA. The homology between this strain and Enterobacter sp. is 99%. The optimum growth conditions are as follows: pH7 at 30°C, 500 mg/L of o-phthalic acid, inoculation concentration ≥ 1.2% and its highest degradation rate of o-phthalic acid is 74%. The results of pot experiment showed that the degradation efficiency of o-phthalic acid in soil was about 40%, which alleviated the inhibitory effect of o-phthalic acid accumulation on tobacco growth.展开更多
Large-aperture solar telescopes play an important role in solar observations and research,and require high temporal and spatial resolution[1].To solve some fundamental problems such as the solar dynamo,coronal heating...Large-aperture solar telescopes play an important role in solar observations and research,and require high temporal and spatial resolution[1].To solve some fundamental problems such as the solar dynamo,coronal heating,and the triggering of major solar eruptions,the spatial resolution for solar-atmosphere observation should reach at least 0.1 arcsec[2].展开更多
Eyeball loss due to severe ocular trauma,intraocular malignancy or infection often requires surgical treatment called orbital implant reconstruction to rehabilitate the orbital volume and restore the aesthetic appeara...Eyeball loss due to severe ocular trauma,intraocular malignancy or infection often requires surgical treatment called orbital implant reconstruction to rehabilitate the orbital volume and restore the aesthetic appearance.However,it remains a challenge to minimize the postoperative exposure and infection complications due to the inert nature of conventional orbital implants.Herein,we developed a novel Ca-Zn-silicate bioceramic implant with multi-functions to achieve the expected outcomes.The porous hardystonite(Ca2ZnSi2O7)scaffolds with triply periodic minimal surfaces(TPMS)-based pore architecture and graded pore size distribution from center to periphery(from 500 to 800μm or vice versa)were fabricated through the digital light processing(DLP)technique,and the scaffolds with homogeneous pores(500 or 800μm)were fabricated as control.The graded porous scaffolds exhibited a controlled bio-dissolving behavior and intermediate mechanical strength in comparison with the homogeneous counterparts,although all of porous implants presented significant antibacterial potential against S.aureus and E.coli.Meanwhile,the pore size-increasing scaffolds indicated more substantial cell adhesion,cell viability and angiogenesis-related gene expression in vitro.Furthermore,the gradually increasing pore feature exhibited a stronger blood vessel infiltrating potential in the dorsal muscle embedding model,and the spherical implants with such pore structure could achieve complete vascularization within 4 weeks in the eyeball enucleation rabbit models.Overall,our results suggested that the novel antibacterial hardystonite bioceramic with graded pore design has excellent potential as a next-generation orbital implant,and the pore topological features offer an opportunity for the improvement of biological performances in orbital reconstruction.展开更多
With the goal of predicting the future rainfall intensity in a local region over a relatively short period time,precipitation nowcasting has been a long-time scientific challenge with great social and economic impact....With the goal of predicting the future rainfall intensity in a local region over a relatively short period time,precipitation nowcasting has been a long-time scientific challenge with great social and economic impact.The radar echo extrapolation approaches for precipitation nowcasting take radar echo images as input,aiming to generate future radar echo images by learning from the historical images.To effectively handle complex and high non-stationary evolution of radar echoes,we propose to decompose the movement into optical flow field motion and morphologic deformation.Following this idea,we introduce Flow-Deformation Network(FDNet),a neural network that models flow and deformation in two parallel cross pathways.The flow encoder captures the optical flow field motion between consecutive images and the deformation encoder distinguishes the change of shape from the translational motion of radar echoes.We evaluate the proposed network architecture on two real-world radar echo datasets.Our model achieves state-of-the-art prediction results compared with recent approaches.To the best of our knowledge,this is the first network architecture with flow and deformation separation to model the evolution of radar echoes for precipitation nowcasting.We believe that the general idea of this work could not only inspire much more effective approaches but also be applied to other similar spatio-temporal prediction tasks.展开更多
Breast cancer(BC)is among the commonly diagnosed malignancies,which displaced lung cancer to become the most leading diagnosed cancer worldwide in 2020.^([1])Approximately 15%to 20%of BC patients are positive for the ...Breast cancer(BC)is among the commonly diagnosed malignancies,which displaced lung cancer to become the most leading diagnosed cancer worldwide in 2020.^([1])Approximately 15%to 20%of BC patients are positive for the human epidermal growth factor receptor 2 gene(Her-2)and exhibits a high degree of malignancy.However,the definition of Her-2 positivity remains controversial and fluctuating.展开更多
In this paper,we study the prize-collecting k-Steiner tree(PCkST) problem.We are given a graph G=(V,E) and an integer k.The graph is connected and undirected.A vertex r ∈ V called root and a subset R?V called termina...In this paper,we study the prize-collecting k-Steiner tree(PCkST) problem.We are given a graph G=(V,E) and an integer k.The graph is connected and undirected.A vertex r ∈ V called root and a subset R?V called terminals are also given.A feasible solution for the PCkST is a tree F rooted at r and connecting at least k vertices in R.Excluding a vertex from the tree incurs a penalty cost,and including an edge in the tree incurs an edge cost.We wish to find a feasible solution with minimum total cost.The total cost of a tree F is the sum of the edge costs of the edges in F and the penalty costs of the vertices not in F.We present a simple approximation algorithm with the ratio of 5.9672 for the PCkST.This algorithm uses the approximation algorithms for the prize-collecting Steiner tree(PCST) problem and the k-Steiner tree(kST) problem as subroutines.Then we propose a primal-dual based approximation algorithm and improve the approximation ratio to 5.展开更多
China’s traffic safety attracts increasing research interest.Official data show that crashes in the western region of China are more severe than those in the eastern region.However,research on crash severity in weste...China’s traffic safety attracts increasing research interest.Official data show that crashes in the western region of China are more severe than those in the eastern region.However,research on crash severity in western China is scarce.This study applied a hierarchical Bayesian logistic model to examine the significant factors related to crash and vehicle/driver levels and their heterogeneous impacts on the severity of drivers’ injury.Crash data were collected from Lintao,a rural mountainous county in western China.A variable was proposed to measure the relative difference between the crashworthiness of one vehicle and the aggressivity of the other vehicle in the mixed traffic flow.Results indicated that the majority of the total variance was induced by between-crash variance,showing the suitability of the utilized hierarchical modeling approach.One crash-level variable and six vehicle/driver-level variables,namely,road type,compatibility difference,age,vehicle type,drunk driving,driving unregistered vehicle,and driving years,significantly affected modeling drivers’ injury severities.Among these variables,road type(national and provincial),age(young and senior drivers),driving unregistered vehicle,and drunk driving tended to increase the odds of crash-related mortality.Driving years(new drivers with less than six years of driving experience) and vehicle type(heavy vehicle) were likely to decrease the probability of fatal outcomes.Compatibility difference was relatively significant,and the possibilities of mortality in single vehicle crashes were higher than those inmultivehicle and pedestrian-involved crashes.The developed methodology and estimation results provided insights into the internal mechanism of rural crashes and effective countermeasures to prevent rural crashes.展开更多
Prosthetic eye is indispensable as filler after enucleation in patients with anophthalmia,whereas there are still many complications including postoperative infection and eye socket depression or extrusion during the ...Prosthetic eye is indispensable as filler after enucleation in patients with anophthalmia,whereas there are still many complications including postoperative infection and eye socket depression or extrusion during the conventional artificial eye material applications.Some Ca-silicate biomaterials showed superior bioactivity but their biological stability in vivo limit the biomedical application as long-term or permanent implants.Herein we aimed to understand the physicochemical and potential biological responses of zinc doping in wollastonite bioceramic used for orbital implants.The wollastonite powders with different zinc dopant contents(CSi-Znx)could be fabricated as porous implants with strut or curve surface pore geometries(cubic,IWP)via ceramic stereolithography.The experimental results indicated that,by increasing zinc-substituting-Ca ratio(up to 9%),the sintering and mechanical properties could be significantly enhanced,and meanwhile the bio-dissolution in vitro and biodegradability in vivo were thoroughly inhibited.In particular,an appreciable angiogenic activity and expected antibacterial efficacy(over 90%)were synergistically achieved at 9 mol%Zn dopant.In the back-embedding and enucleation and implantation model experiments in rabbits,the superior continuous angiogenesis was corroborated from the 2D/3D fibrovascular reconstruction in the IWP-pore CSi-Zn9 and CSi-Zn13.5 groups within very short time stages.Totally,the present silicate-based bioceramic via selective Zn doping could produce outstanding structural stability and bifunctional biological responses which is especially valuable for developing the next-generation implants with vascular insertion and fixation in orbital reconstruction prothesis.展开更多
文摘Studying the relationship between rhizosphere microorganisms and root exudates is of great significance for the interaction between rhizosphere microorganisms and plants, and the prevention and control of soil-borne diseases. This article analyzed the effects of different microorganisms on tobacco root exudates and rhizosphere microorganisms. It was found that the bacterial wilt pathogen can greatly increase acids and amines, while the probiotic <i>B. amyloliquefaciens</i> ZM9 can eliminate some acids and amines. The results of the study show that the root exudates of pathogenic bacteria may contain a variety of allelochemicals that cause soil-borne diseases.
基金Supported by the Administration of Traditional Chinese Medicine of Guangdong Province,China (No. 2010431)
文摘OBJECTIVE:To observe the curative effect of an acupoint application with a Dingqi analgesic patch on moderate to severe pain caused by liver cancer.METHODS:Forty patients with moderate to severe pain caused by liver cancer were randomly divided intoatreatmentgroup(TG)andacontrolgroup(CG).Patients with moderate pain were given 100 mg qd of a sustainably released tablet of tramadol hydrochloride;patientswithseverepainweregiven4.2mg q3d of the fentanyl transdermal system.The ashi points Ganshu(BL 18),Danshu(BL 19) and Qimen(LR 14) were chosen for the acupoint application intervention.CG patients were given a sham patch and TG patients were given a Dingqi analgesic patch.A visual analogue scale(VAS) was used before treatment and after 1,3,6,9 and 12 days of treatment.The Karnofsky score was measured before treatment and after 12 days of treatment.Any main adverse reactions(e.g.nausea,constipation,dizziness and headache) were recorded after 6 and 12 days of treatment.Any skin side effects(i.e.skin irritation and allergic reactions) were recorded.RESULTS:The VAS in TG was significantly lower than that in CG after 3,6,9 and 12 days of treatment(P<0.05).There was no significant difference in the Karnofsky score before treatment and after 12 days of treatment between CG and TG.There were also no significant differences in the main adverse reactions or skin side effects after 6 and 12 days of treatment between CG andTG(P>0.05).CONCLUSION:The Dingqi analgesic patch can enhance the analgesic effect of tramadol and fentanyl.
文摘The consensus of the automotive industry and traffic management authorities is that autonomous vehicles must follow the same traffic laws as human drivers.Using formal or digital methods,natural language traffic rules can be translated into machine language and used by autonomous vehicles.In this paper,a translation flow is designed.Beyond the translation,a deeper examination is required,because the semantics of natural languages are rich and complex,and frequently contain hidden assumptions.The issue of how to ensure that digital rules are accurate and consistent with the original intent of the traffic rules they represent is both significant and unresolved.In response,we propose a method of formal verification that combines equivalence verification with model checking.Reasonable and reassuring digital traffic rules can be obtained by utilizing the proposed traffic rule digitization flow and verification method.In addition,we offer a number of simulation applications that employ digital traffic rules to assess vehicle violations.The experimental findings indicate that our digital rules utilizing metric temporal logic(MTL)can be easily incorporated into simulation platforms and autonomous driving systems(ADS).
基金supported by the National High Technology Research and Development Program of China(863 Program,No.2007AA02Z418)
文摘Objective：Rabies is invariably a fatal encephalomyelitis that is considered to be a serious public health problem.It is necessary to develop standard rabies virus diagnostic tools,especially for diagnosing the strains prevalent in China.Methods：Monoclonal antibodies（MAbs）specific to rabies virus were produced and characterized by enzyme linked immunosorbent assay（ELISA）,isotyping,affinity assay,immunofluorescence assay（IFA）,and immunocytochemistry.The MAb,whose affinity was higher for antigen,was used to establish an antigen captureELISA（AC-ELISA）detection system and test the efficiency by using clinical samples.Results：The heavy chain subclasses of two MAbs were all determined to be IgG2a.The 3C7 MAb showed stronger reactivity with rabies virus protein than the 2C5 MAb in an ELISA analysis,whereas the 3C7 MAb showed the highest affinity for antigen.IFA and immunocytochemistry results also indicated that the two MAbs could recognize rabies virus protein in its native form in cell samples.Data obtained using clinical samples showed that rabies virus could be detected by AC-ELISA detection system using the 3C7 MAb.Conclusion：It was potentially useful for the further development of highly sensitive,easily handled,and relatively rapid detection kits/tools for rabies surveillance in those areas where rabies is endemic,especially in China.
基金supported by the Innovation Fund of China Steel Research Technology Group Co.,Ltd.,(No.KNJT05-JT0M-21001)the National Natural Science Foundation of China(No.51971036)the National Key Research and Development Program of China(No.2021YFB3701900).
文摘In this study,the PH13-8Mo stainless steel parts doped without and with cerium(Ce)were fabricated via laser powder bed fusion followed by post-heat treatment,and systematically compared in terms of microstructure,phase constituent,and tensile properties.The comparative results show that doping Ce-modified grains with the equiaxed morphology and finer size,increased the mechanical stability of austenite,and enhanced the sphericity of oxide inclusion in the resultant PH13-8Mo.Additionally,the coherency between the newly-formed CeAlO 3 inclusion and matrix was effectively im proved after doping Ce,as compared to the original aluminum oxide inclusion without doping Ce.The resultant PH13-8Mo parts doped with Ce yielded an ultimate tensile strength of 1446±20 MPa with a fracture elongation of 16.0%±1.5%,for the first time meeting the AMS 5629E H1000 standard for the PH13-8Mo made by additive manufacturing(AM).The enhanced strength results from the strengthening effects of nanoscale precipitation(inclusion)and grain refining.Meanwhile,the ductilizing mechanism can be attributed to the enhanced inclusion sphericity and ameliorative coherency between the inclusion and matrix,and improved misorientation angle of grain boundary owing to the modification by Ce,which efficiently re-duced the stress concentration and enhanced cracking resistance during deformation.Therefore,doping rare earth elements presents a promising pathway to synergistically improve the strength and ductility of stainless steels by AM.
基金supported by the Natural Science Foundation of Zhejiang Province(LY19H160009 and LY20H120007)the National Natural Science Foundation of China(82130053,81971871,31970845 and 81901571)+1 种基金the Joint Preresearch Fund for Clinical Scientific Research of Hangzhou First People’s Hospital Affiliated to Zhejiang University(YYJJ2019Z07)the Major Project of Hangzhou Health Science and Technology Plan(Z20200134).
文摘Although chimeric antigen receptor-modified(CAR)T cell therapy has been successfully applied in the treatment of acute B lymphocytic leukemia,its effect on Burkitt lymphoma(BL)and chronic B lymphocytic leukemia(B-CLL)is unsatisfactory.Moreover,fatal side effects greatly impede CAR T cell application.Extracellular vesicles(EVs)are excellent carriers of therapeutic agents.Nevertheless,EVs mainly accumulate in the liver when administered without modification.As an envelope glycoprotein of Epstein–Barr viruses,gp350 can efficiently bind CD21 on B cells.Here,gp350 was directly anchored onto red blood cell EVs(RBC-EVs)via its transmembrane region combined with low-voltage electroporation.The results showed that gp350 could anchor to RBC-EVs with high efficiency and that the resulting gp350-anchored RBC-EVs(RBC-EVs/gp350^(Etp))exhibited increased targeting to CD21+BL and B-CLL relative to RBC-EVs.After the loading of doxorubicin or fludarabine,RBC-EVs/gp350^(Etp) had powerful cytotoxicity and therapeutic efficacy on CD21+BL or B-CLL,respectively.Moreover,RBC-EVs/gp350^(Etp) loaded with a drug did not exhibit any apparent systemic toxicity and specifically induced the apoptosis of tumor B cells but not normal Bcells.Therefore,our findings indicate that drug-loaded RBC-EVs/gp350^(Etp) may be adopted in the treatment of CD21+B cell malignancies.
文摘In order to improve the spore yield of compound Bacillus spp. (B. amyloliquefaciens, B. laterosporus and B. megaterium), the effects of nutrient conditions including carbon source, nitrogen source, mineral salt and fermentation conditions including the inoculum age, inoculation amount, loading volume of liquid and initial pH on the spore yield were studied. The results indicated that the optimized medium was glucoses 20 g/L, soybean meal 30.0 g/L, K2HPO4 1.0 g/L;fermentation temperature is 37℃, the inoculum age 12 h, initial pH 7.0, 2% inoculation amount, loading volume of liquid 20 mL/250 mL. Under the optimized conditions of culture medium and fermentation for compound Bacillus spp., spore yield was 10.24 times more than the initial medium, and the spore formation rate reached more than 90%.
文摘The research on relationship between rhizosphere microbes and root exudates has a great significance on discussion of interaction between rhizosphere microbes and plants, as well as control of soil-borne diseases and insect pest. GC-MS was used to analyze changes of tobacco root exudates under the antagonistic action of tobacco bacterial wilt and black shank. It turned out that when pathogens of tobacco bacterial wilt and black shank in tobacco root microorganisms increase, tobacco root exudates augmented rapidly among of which organic acids have the biggest growth, followed by amines. When the pathogens of tobacco bacterial wilt and black shank are inhibited by the active substance of antagonistic antibacterial, 20 - 23 kinds of root exudates are added;besides, the content of 7 substances was reduced to 0. Another inter-esting finding was that the fluctuations of phthalic acid, isophthalic acid and benzoic acid, which have caused continuous cropping obstacles, were very dis-tinct. The results of this study have provided novel clues for the exploration of continuous tobacco cropping obstacles and soil-borne diseases.
文摘O-phthalic acid is a kind of important pollutant, which accumulates in the environment with the extensive use of plastics and other products. Meanwhile, phthalic acid is one of the high content of allelopathic autotoxic substances secreted by tobacco. The accumulation of phthalic acid in soil is an important cause of tobacco continuous cropping effect. In order to degrade phthalic acid accumulated in environment, the barrier effect of tobacco continuous cropping caused by phthalic acid accumulation in soil can be removed. A strain capable of degrading phthalic acid was isolated from sludge of sewage treatment plant and compared with 16 s DNA. The homology between this strain and Enterobacter sp. is 99%. The optimum growth conditions are as follows: pH7 at 30°C, 500 mg/L of o-phthalic acid, inoculation concentration ≥ 1.2% and its highest degradation rate of o-phthalic acid is 74%. The results of pot experiment showed that the degradation efficiency of o-phthalic acid in soil was about 40%, which alleviated the inhibitory effect of o-phthalic acid accumulation on tobacco growth.
基金supported by the National Natural Science Foundation of China(Grant No.11727805)the Youth Innovation Promotion Association,Chinese Academy of Sciences(Grant No.2018412)。
文摘Large-aperture solar telescopes play an important role in solar observations and research,and require high temporal and spatial resolution[1].To solve some fundamental problems such as the solar dynamo,coronal heating,and the triggering of major solar eruptions,the spatial resolution for solar-atmosphere observation should reach at least 0.1 arcsec[2].
基金support from the National Natural Science Foundation of China(81870635,82000948)the National Key Research and Development Program of China(2017YFE0117700)and Natural Science Foundation of Zhejiang Province(LY20H120007).
文摘Eyeball loss due to severe ocular trauma,intraocular malignancy or infection often requires surgical treatment called orbital implant reconstruction to rehabilitate the orbital volume and restore the aesthetic appearance.However,it remains a challenge to minimize the postoperative exposure and infection complications due to the inert nature of conventional orbital implants.Herein,we developed a novel Ca-Zn-silicate bioceramic implant with multi-functions to achieve the expected outcomes.The porous hardystonite(Ca2ZnSi2O7)scaffolds with triply periodic minimal surfaces(TPMS)-based pore architecture and graded pore size distribution from center to periphery(from 500 to 800μm or vice versa)were fabricated through the digital light processing(DLP)technique,and the scaffolds with homogeneous pores(500 or 800μm)were fabricated as control.The graded porous scaffolds exhibited a controlled bio-dissolving behavior and intermediate mechanical strength in comparison with the homogeneous counterparts,although all of porous implants presented significant antibacterial potential against S.aureus and E.coli.Meanwhile,the pore size-increasing scaffolds indicated more substantial cell adhesion,cell viability and angiogenesis-related gene expression in vitro.Furthermore,the gradually increasing pore feature exhibited a stronger blood vessel infiltrating potential in the dorsal muscle embedding model,and the spherical implants with such pore structure could achieve complete vascularization within 4 weeks in the eyeball enucleation rabbit models.Overall,our results suggested that the novel antibacterial hardystonite bioceramic with graded pore design has excellent potential as a next-generation orbital implant,and the pore topological features offer an opportunity for the improvement of biological performances in orbital reconstruction.
基金supported in part by the National Key Research and Development Program of China under Grant No.2018YFC0831500the Beijing Natural Science Foundation under Grant No.JQ18001,and the Beijing Academy of Artificial Intelligence.
文摘With the goal of predicting the future rainfall intensity in a local region over a relatively short period time,precipitation nowcasting has been a long-time scientific challenge with great social and economic impact.The radar echo extrapolation approaches for precipitation nowcasting take radar echo images as input,aiming to generate future radar echo images by learning from the historical images.To effectively handle complex and high non-stationary evolution of radar echoes,we propose to decompose the movement into optical flow field motion and morphologic deformation.Following this idea,we introduce Flow-Deformation Network(FDNet),a neural network that models flow and deformation in two parallel cross pathways.The flow encoder captures the optical flow field motion between consecutive images and the deformation encoder distinguishes the change of shape from the translational motion of radar echoes.We evaluate the proposed network architecture on two real-world radar echo datasets.Our model achieves state-of-the-art prediction results compared with recent approaches.To the best of our knowledge,this is the first network architecture with flow and deformation separation to model the evolution of radar echoes for precipitation nowcasting.We believe that the general idea of this work could not only inspire much more effective approaches but also be applied to other similar spatio-temporal prediction tasks.
文摘Breast cancer(BC)is among the commonly diagnosed malignancies,which displaced lung cancer to become the most leading diagnosed cancer worldwide in 2020.^([1])Approximately 15%to 20%of BC patients are positive for the human epidermal growth factor receptor 2 gene(Her-2)and exhibits a high degree of malignancy.However,the definition of Her-2 positivity remains controversial and fluctuating.
基金supported by the National Natural Science Foundation of China (Nos. 12001523,11971046,12131003,and 11871081)the Scientific Research Project of Beijing Municipal Education Commission (No. KM201910005012)Beijing Natural Science Foundation Project (No. Z200002)。
文摘In this paper,we study the prize-collecting k-Steiner tree(PCkST) problem.We are given a graph G=(V,E) and an integer k.The graph is connected and undirected.A vertex r ∈ V called root and a subset R?V called terminals are also given.A feasible solution for the PCkST is a tree F rooted at r and connecting at least k vertices in R.Excluding a vertex from the tree incurs a penalty cost,and including an edge in the tree incurs an edge cost.We wish to find a feasible solution with minimum total cost.The total cost of a tree F is the sum of the edge costs of the edges in F and the penalty costs of the vertices not in F.We present a simple approximation algorithm with the ratio of 5.9672 for the PCkST.This algorithm uses the approximation algorithms for the prize-collecting Steiner tree(PCST) problem and the k-Steiner tree(kST) problem as subroutines.Then we propose a primal-dual based approximation algorithm and improve the approximation ratio to 5.
基金The research reported in this paper is part of the project supported by the National Natural Science Foundation of China (71871123)。
文摘China’s traffic safety attracts increasing research interest.Official data show that crashes in the western region of China are more severe than those in the eastern region.However,research on crash severity in western China is scarce.This study applied a hierarchical Bayesian logistic model to examine the significant factors related to crash and vehicle/driver levels and their heterogeneous impacts on the severity of drivers’ injury.Crash data were collected from Lintao,a rural mountainous county in western China.A variable was proposed to measure the relative difference between the crashworthiness of one vehicle and the aggressivity of the other vehicle in the mixed traffic flow.Results indicated that the majority of the total variance was induced by between-crash variance,showing the suitability of the utilized hierarchical modeling approach.One crash-level variable and six vehicle/driver-level variables,namely,road type,compatibility difference,age,vehicle type,drunk driving,driving unregistered vehicle,and driving years,significantly affected modeling drivers’ injury severities.Among these variables,road type(national and provincial),age(young and senior drivers),driving unregistered vehicle,and drunk driving tended to increase the odds of crash-related mortality.Driving years(new drivers with less than six years of driving experience) and vehicle type(heavy vehicle) were likely to decrease the probability of fatal outcomes.Compatibility difference was relatively significant,and the possibilities of mortality in single vehicle crashes were higher than those inmultivehicle and pedestrian-involved crashes.The developed methodology and estimation results provided insights into the internal mechanism of rural crashes and effective countermeasures to prevent rural crashes.
基金the National Natural Science Foundation Regional Innovation and Development Joint Fund(U20A20386)the Zhejiang Provincial Basic Research for Public Welfare Funds(LGF22E030002)+1 种基金National Natural Science Foundation of China(82330032,82201236)Zhejiang Provincial Natural Science Foundation of China(LZ22E020002).
文摘Prosthetic eye is indispensable as filler after enucleation in patients with anophthalmia,whereas there are still many complications including postoperative infection and eye socket depression or extrusion during the conventional artificial eye material applications.Some Ca-silicate biomaterials showed superior bioactivity but their biological stability in vivo limit the biomedical application as long-term or permanent implants.Herein we aimed to understand the physicochemical and potential biological responses of zinc doping in wollastonite bioceramic used for orbital implants.The wollastonite powders with different zinc dopant contents(CSi-Znx)could be fabricated as porous implants with strut or curve surface pore geometries(cubic,IWP)via ceramic stereolithography.The experimental results indicated that,by increasing zinc-substituting-Ca ratio(up to 9%),the sintering and mechanical properties could be significantly enhanced,and meanwhile the bio-dissolution in vitro and biodegradability in vivo were thoroughly inhibited.In particular,an appreciable angiogenic activity and expected antibacterial efficacy(over 90%)were synergistically achieved at 9 mol%Zn dopant.In the back-embedding and enucleation and implantation model experiments in rabbits,the superior continuous angiogenesis was corroborated from the 2D/3D fibrovascular reconstruction in the IWP-pore CSi-Zn9 and CSi-Zn13.5 groups within very short time stages.Totally,the present silicate-based bioceramic via selective Zn doping could produce outstanding structural stability and bifunctional biological responses which is especially valuable for developing the next-generation implants with vascular insertion and fixation in orbital reconstruction prothesis.
