BACKGROUND As reported,multiple circular RNAs(circRNAs)interfere with colorectal cancer(CRC)progression.Here,circRNA_0001658(circ_0001658)is focused on studying how it works in CRC.AIM Clarify the expression pattern,b...BACKGROUND As reported,multiple circular RNAs(circRNAs)interfere with colorectal cancer(CRC)progression.Here,circRNA_0001658(circ_0001658)is focused on studying how it works in CRC.AIM Clarify the expression pattern,biological function,and underlying mechanism of circ_0001658 of CRC tumorigenesis.METHODS In CRC-related chip data retrieved using the database named Gene Expression Omnibus,different expressions of circRNAs between CRC and normal tissue samples were identified.Quantitative Real-time PCR and Western blot ensured the analysis on circ_0001658,microRNA-590-5P(miR-590-5p),and methyltransferase-like 3(METTL3)mRNA expressions in tissues and cells.Cell counting kit-8 and flow cytometry were used to detect cell proliferation,apoptosis and migration.The targeting relations between circ_0001658,miR-590-5p,and METTL3 mRNA 3'-untranslated region were under the verification of bioinformatics prediction and dual luciferase-based reporter gene assays.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis were employed on the downstream targets of miR-590-5p using the Database for Annotation,Visualization and Integrated Discovery database.RESULTS Circ_0001658 and METTL3 mRNA was elevated in CRC tissues and cells,whereas miR-590-5p was decreased.Circ_0001658 overexpression promoted the proliferation of HT29 cells,inhibited apoptosis,and accelerated the cell cycle.In SW480 cells,knocking down circ_0001658 had the opposite effect.Circ_0001658 could specifically bind to miR-590-5p and negatively modulate its expressions;METTL3 is a miR-590-5p target that can be positively regulated by circ 0001658.Circ 0001658 was inversely associated with miR-590-5p expression while positively with METTL3 expressions.CONCLUSION Circ_0001658 regulates the miR-590-5p/METTL 3-axis to increase CRC cell growth and decrease apoptosis.展开更多
The separation and recovery of Ni from the copper electrolyte by crystallization of nickel ammonium sulfate double salt were studied.It is found that the solubility of copper sulfate at the same temperature is less th...The separation and recovery of Ni from the copper electrolyte by crystallization of nickel ammonium sulfate double salt were studied.It is found that the solubility of copper sulfate at the same temperature is less than that of nickel sulfate,while the solubility of copper ammonium sulfate is greater than that of nickel ammonium sulfate.So,by adding(NH_(4))_(2)SO_(4),the Ni can be selectively crystallized from the copper electrolyte.By adding(NH_(4))_(2)SO_(4)at the molar ratio of(NH_(4))_(2)SO_(4)/NiSO_(4)≤0.8,and crystallizing at−15℃for 10 h,the Ni in the copper electrolyte can be crystallized in the form of Ni(NH_(4))_(2)(SO_(4))_(2)×6H_(2)O.The qualified product of NiSO_(4)×6H_(2)O can be obtained by pyrolyzing the crystals,dissolving the pyrolysis product in water,and then concentrating the dissolved solution for crystallization.The method of double salt crystallization is a clean,environmentally-friendly,cost-effective and efficient method for separating and recovering nickel from copper electrolyte.展开更多
Nano-silicon(nano-Si)and its composites have been regarded as the most promising negative electrode materials for producing the next-generation Li-ion batteries(LIBs),due to their ultrahigh theoretical capacity.Howeve...Nano-silicon(nano-Si)and its composites have been regarded as the most promising negative electrode materials for producing the next-generation Li-ion batteries(LIBs),due to their ultrahigh theoretical capacity.However,the commercial applications of nano Si-based negative electrode materials are constrained by the low cycling stability and high costs.The molten salt electrolysis of SiO_(2)is proven to be suitable to produce nano-Si with the advantages of in-situ microstructure control possibilities,cheap affordability and scale-up process capability.Therefore,an economical approach for electrolysis,with a SiO_(2)/graphite porous electrode as cathode,is adopted to produce nano-Si/graphite composite negative electrode materials(SGNM)in this study.The electrolytic product of the optimized porous electrode is taken as the negative electrode materials for LIBs,and it offers a capacity of 733.2 mAh·g^(-1)and an initial coulombic efficiency of 86.8%in a coin-type cell.Moreover,the capacity of the SGNM retained 74.1%of the initial discharging capacity after 50 cycles at 0.2C,which is significantly higher than that of the simple mixture of silicon and graphite obtained from the formation of silicon carbide(SiC)between nano-Si and graphite particles.Notably,this new approach can be applied to a large-scale production.展开更多
Slow freezing is the most commonly used technique for the cryopreservation of spermatozoa in clinical practice.However,it has been shown to have a negative impact on sperm function and structure.Vitrification as a suc...Slow freezing is the most commonly used technique for the cryopreservation of spermatozoa in clinical practice.However,it has been shown to have a negative impact on sperm function and structure.Vitrification as a successful alternative method has been proved to have better protective effects on human embryos,but vitrification of spermatozoa is still subject to low recovery rates.In this study,a modified vitrification method for native spermatozoa was developed.A total of 28 semen samples were included;each sample was divided into three equal parts and assigned to fresh,slow freezing,and vitrification groups.Sperm vitality,motility,morphology,DNA integrity,and acrosome reaction were assessed for each of the groups.The results showed that vitrification achieves better results for several sperm protection parameters than slow freezing;vitrification achieves a higher recovery rate(P<0.05),motility(P<0.05),morphology(P<0.05),and curve line velocity(P<0.05)than slow freezing.Furthermore,DNA fragmentation was decreased(P<0.05)and better acrosome protection(P<0.05)was exhibited in the spermatozoa after vitrification.Principal component analysis of all sperm parameters revealed that the vitrification cluster was closer to the fresh cluster,indicating that spermatozoa are better preserved through vitrification.In conclusion,while both slow freezing and vitrification have negative effects on sperm function and structure,the vitrification protocol described here had a relatively better recovery rate(65.8%)and showed improved preservation of several sperm quality parameters compared with slow freezing.展开更多
At present,Nb_(3) Sn superconductors are becoming more popular in high magnetic fields.The growth law of Nb_(3) Sn phase in a planar CuSn/Nb diffusion couple has been studied,whereas the formation mechanism of Nb_(3) ...At present,Nb_(3) Sn superconductors are becoming more popular in high magnetic fields.The growth law of Nb_(3) Sn phase in a planar CuSn/Nb diffusion couple has been studied,whereas the formation mechanism of Nb_(3) Sn phase in a cylindrical CuSn/Nb diffusion couple is still controversial.The purpose of this work is to investigate the growth exponent of Nb_(3) Sn phase at the initial stage of annealing by use of scanning electron microscopy(SEM)through which the thickness of Nb_(3) Sn layer can be obtained.In this study,bronze-processed Nb_(3) Sn multifilamentary wires with different annealing time were investigated.The Nb_(3) Sn phase was formed during isothermal annealing at 670 ℃ by solid-state diffusion,which was accomplished by the movement of Sn atoms from the CuSn/Nb_(3) Sn interface to Nb_(3) Sn/Nb interface.However,the formation mechanism of Nb_(3) Sn phase at the initial stage of annealing is still not well understood.Microstructural evolution of Nb_(3) Sn phase during isothermal annealing was studied by SEM.The mean thickness of the Nb_(3) Sn layer(Δ(xNn3 Sn)) is expressed as a power function of the annealing time(t) by the equation A_(x^(2)Nb_(3) Sn)=k(t/t0)^(n),where t0 is the unit time,k is the reaction rate constant and n is the growth exponent.The growth exponent has the average value of 0.82,which means that the formation of the Nb_(3) Sn phase is both governed by the interface reaction and the grain boundary diffusion.展开更多
Using boron powder as additive, the preparation of zirconium diboride(ZrB 2) by carbothermal reduction was investigated. The results show that the carbothermal reduction cannot be completely done until the temperature...Using boron powder as additive, the preparation of zirconium diboride(ZrB 2) by carbothermal reduction was investigated. The results show that the carbothermal reduction cannot be completely done until the temperature is more than 1900 ℃. The ZrB2 particles prepared without boron(B) additive at 1900 ℃ for 3 h are rodlike and show a preferential grain growth along [001] direction. B additive changes the heat effect of the raw materials. With B additive, the morphology of ZrB2 particles turns to be regular shape. The average particle size is about 3.6 μm with 2.5 wt% B additives. With more B additive, the shape of particles turns to be round like and the average particle size is decreased to 2.3 μm when 5 wt% B is added. The existence of oxides in grain boundary is a key factor to keep ZrB2 ceramic from deep densification. Using ZrB2 powder prepared with 5 wt% B additives, by controlling carbon content in ZrB2 powder, ZrB2 ceramic with 93%relative density is hot-pressed.展开更多
文摘BACKGROUND As reported,multiple circular RNAs(circRNAs)interfere with colorectal cancer(CRC)progression.Here,circRNA_0001658(circ_0001658)is focused on studying how it works in CRC.AIM Clarify the expression pattern,biological function,and underlying mechanism of circ_0001658 of CRC tumorigenesis.METHODS In CRC-related chip data retrieved using the database named Gene Expression Omnibus,different expressions of circRNAs between CRC and normal tissue samples were identified.Quantitative Real-time PCR and Western blot ensured the analysis on circ_0001658,microRNA-590-5P(miR-590-5p),and methyltransferase-like 3(METTL3)mRNA expressions in tissues and cells.Cell counting kit-8 and flow cytometry were used to detect cell proliferation,apoptosis and migration.The targeting relations between circ_0001658,miR-590-5p,and METTL3 mRNA 3'-untranslated region were under the verification of bioinformatics prediction and dual luciferase-based reporter gene assays.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis were employed on the downstream targets of miR-590-5p using the Database for Annotation,Visualization and Integrated Discovery database.RESULTS Circ_0001658 and METTL3 mRNA was elevated in CRC tissues and cells,whereas miR-590-5p was decreased.Circ_0001658 overexpression promoted the proliferation of HT29 cells,inhibited apoptosis,and accelerated the cell cycle.In SW480 cells,knocking down circ_0001658 had the opposite effect.Circ_0001658 could specifically bind to miR-590-5p and negatively modulate its expressions;METTL3 is a miR-590-5p target that can be positively regulated by circ 0001658.Circ 0001658 was inversely associated with miR-590-5p expression while positively with METTL3 expressions.CONCLUSION Circ_0001658 regulates the miR-590-5p/METTL 3-axis to increase CRC cell growth and decrease apoptosis.
基金the National Natural Science Foundation of China(No.50274075).
文摘The separation and recovery of Ni from the copper electrolyte by crystallization of nickel ammonium sulfate double salt were studied.It is found that the solubility of copper sulfate at the same temperature is less than that of nickel sulfate,while the solubility of copper ammonium sulfate is greater than that of nickel ammonium sulfate.So,by adding(NH_(4))_(2)SO_(4),the Ni can be selectively crystallized from the copper electrolyte.By adding(NH_(4))_(2)SO_(4)at the molar ratio of(NH_(4))_(2)SO_(4)/NiSO_(4)≤0.8,and crystallizing at−15℃for 10 h,the Ni in the copper electrolyte can be crystallized in the form of Ni(NH_(4))_(2)(SO_(4))_(2)×6H_(2)O.The qualified product of NiSO_(4)×6H_(2)O can be obtained by pyrolyzing the crystals,dissolving the pyrolysis product in water,and then concentrating the dissolved solution for crystallization.The method of double salt crystallization is a clean,environmentally-friendly,cost-effective and efficient method for separating and recovering nickel from copper electrolyte.
基金This work was financially supported by the National Key Research and Development Program of China(No.2016YFB0301305)the Talent Plan Project of Beijing(No.2018000097607G378)the National Natural Science Foundation of China(U166420031).
文摘Nano-silicon(nano-Si)and its composites have been regarded as the most promising negative electrode materials for producing the next-generation Li-ion batteries(LIBs),due to their ultrahigh theoretical capacity.However,the commercial applications of nano Si-based negative electrode materials are constrained by the low cycling stability and high costs.The molten salt electrolysis of SiO_(2)is proven to be suitable to produce nano-Si with the advantages of in-situ microstructure control possibilities,cheap affordability and scale-up process capability.Therefore,an economical approach for electrolysis,with a SiO_(2)/graphite porous electrode as cathode,is adopted to produce nano-Si/graphite composite negative electrode materials(SGNM)in this study.The electrolytic product of the optimized porous electrode is taken as the negative electrode materials for LIBs,and it offers a capacity of 733.2 mAh·g^(-1)and an initial coulombic efficiency of 86.8%in a coin-type cell.Moreover,the capacity of the SGNM retained 74.1%of the initial discharging capacity after 50 cycles at 0.2C,which is significantly higher than that of the simple mixture of silicon and graphite obtained from the formation of silicon carbide(SiC)between nano-Si and graphite particles.Notably,this new approach can be applied to a large-scale production.
基金This work was supported by National Natural Science Foundation of China(No.31472054)the National Key Research and Development Program of China(2016YFC1000600).
文摘Slow freezing is the most commonly used technique for the cryopreservation of spermatozoa in clinical practice.However,it has been shown to have a negative impact on sperm function and structure.Vitrification as a successful alternative method has been proved to have better protective effects on human embryos,but vitrification of spermatozoa is still subject to low recovery rates.In this study,a modified vitrification method for native spermatozoa was developed.A total of 28 semen samples were included;each sample was divided into three equal parts and assigned to fresh,slow freezing,and vitrification groups.Sperm vitality,motility,morphology,DNA integrity,and acrosome reaction were assessed for each of the groups.The results showed that vitrification achieves better results for several sperm protection parameters than slow freezing;vitrification achieves a higher recovery rate(P<0.05),motility(P<0.05),morphology(P<0.05),and curve line velocity(P<0.05)than slow freezing.Furthermore,DNA fragmentation was decreased(P<0.05)and better acrosome protection(P<0.05)was exhibited in the spermatozoa after vitrification.Principal component analysis of all sperm parameters revealed that the vitrification cluster was closer to the fresh cluster,indicating that spermatozoa are better preserved through vitrification.In conclusion,while both slow freezing and vitrification have negative effects on sperm function and structure,the vitrification protocol described here had a relatively better recovery rate(65.8%)and showed improved preservation of several sperm quality parameters compared with slow freezing.
基金financially supported by the Nuclear Material Technology Innovation Center for National Defense Technology and Industry(No.ICNM-2019-YZ-03)。
文摘At present,Nb_(3) Sn superconductors are becoming more popular in high magnetic fields.The growth law of Nb_(3) Sn phase in a planar CuSn/Nb diffusion couple has been studied,whereas the formation mechanism of Nb_(3) Sn phase in a cylindrical CuSn/Nb diffusion couple is still controversial.The purpose of this work is to investigate the growth exponent of Nb_(3) Sn phase at the initial stage of annealing by use of scanning electron microscopy(SEM)through which the thickness of Nb_(3) Sn layer can be obtained.In this study,bronze-processed Nb_(3) Sn multifilamentary wires with different annealing time were investigated.The Nb_(3) Sn phase was formed during isothermal annealing at 670 ℃ by solid-state diffusion,which was accomplished by the movement of Sn atoms from the CuSn/Nb_(3) Sn interface to Nb_(3) Sn/Nb interface.However,the formation mechanism of Nb_(3) Sn phase at the initial stage of annealing is still not well understood.Microstructural evolution of Nb_(3) Sn phase during isothermal annealing was studied by SEM.The mean thickness of the Nb_(3) Sn layer(Δ(xNn3 Sn)) is expressed as a power function of the annealing time(t) by the equation A_(x^(2)Nb_(3) Sn)=k(t/t0)^(n),where t0 is the unit time,k is the reaction rate constant and n is the growth exponent.The growth exponent has the average value of 0.82,which means that the formation of the Nb_(3) Sn phase is both governed by the interface reaction and the grain boundary diffusion.
基金financially supported by the National Natural Science Foundation of China(No. 51674035)
文摘Using boron powder as additive, the preparation of zirconium diboride(ZrB 2) by carbothermal reduction was investigated. The results show that the carbothermal reduction cannot be completely done until the temperature is more than 1900 ℃. The ZrB2 particles prepared without boron(B) additive at 1900 ℃ for 3 h are rodlike and show a preferential grain growth along [001] direction. B additive changes the heat effect of the raw materials. With B additive, the morphology of ZrB2 particles turns to be regular shape. The average particle size is about 3.6 μm with 2.5 wt% B additives. With more B additive, the shape of particles turns to be round like and the average particle size is decreased to 2.3 μm when 5 wt% B is added. The existence of oxides in grain boundary is a key factor to keep ZrB2 ceramic from deep densification. Using ZrB2 powder prepared with 5 wt% B additives, by controlling carbon content in ZrB2 powder, ZrB2 ceramic with 93%relative density is hot-pressed.