二氧化碳(CO_2)资源化利用是近年来的一个研究热点,利用生物电化学系统还原CO_2生产能源物质是一种新兴技术.在微生物电合成系统(MES)中利用混合微生物富集阴极功能微生物,评估阴极电势对其还原CO_2产甲烷的影响.当阴极电势从-0.70 V降...二氧化碳(CO_2)资源化利用是近年来的一个研究热点,利用生物电化学系统还原CO_2生产能源物质是一种新兴技术.在微生物电合成系统(MES)中利用混合微生物富集阴极功能微生物,评估阴极电势对其还原CO_2产甲烷的影响.当阴极电势从-0.70 V降低到-0.90 V vs Ag/Ag Cl时,MES产甲烷的量和速率都在增加,最大的产甲烷量和速率分别达到了0.265 mol/m^2和0.025 mmol/h.与此同时,MES的电流密度从0.002 A/m^2增加到0.18 A/m^2,阴极产甲烷的库伦效率在49%和90%之间.当阴极电势更负时,MES阴极几乎不产甲烷.扫描电镜分析(SEM)表明,有多种不同形态的微生物吸附在阴极碳毡上,它们的形态主要呈杆状和球状.16S r DNA测序分析表明Methanobacterium是MES阴极生物膜上优势的产甲烷菌.本研究表明,微生物电合成系统还原CO_2产甲烷的阴极电势必须控制在适当的范围内,才能高效地还原CO_2产甲烷.展开更多
AIM: To investigate the clinical presentations associated with bile acid synthesis defects and to describe identification of individual disorders and diagnostic pitfalls. METHODS: We describe semiquantitative determin...AIM: To investigate the clinical presentations associated with bile acid synthesis defects and to describe identification of individual disorders and diagnostic pitfalls. METHODS: We describe semiquantitative determination of 16 urinary bile acid metabolites by electrospray ionization-tandem mass spectrometry. Sample preparation was performed by solid-phase extraction. The total analysis time was 2 min per sample. We determined bile acid metabolites in 363 patients with suspected defects in bile acid metabolism. RESULTS: Abnormal bile acid metabolites were found in 36 patients. Two patients had bile acid synthesis defects but presented with atypical presentations. In 2 other patients who were later shown to be affected by biliary atresia and cystic fibrosis the profile of bile acid metabolites was initially suggestive of a bile acid synthesis defect. Three adult patients suffered from cerebrotendinous xanthomatosis. Nineteen patients had peroxisomal disorders, and 10 patients had cholestatic hepatopathy of other cause. CONCLUSION: Screening for urinary cholanoids should be done in every infant with cholestatic hepatopathy as well as in children with progressive neurological disease to provide specific therapy.展开更多
Induced polarization （IP） 3D tomography with the similar central gradient array combines IP sounding and IP profiling to retrieve 3D resistivity and polarization data rapidly. The method is characterized by high spa...Induced polarization （IP） 3D tomography with the similar central gradient array combines IP sounding and IP profiling to retrieve 3D resistivity and polarization data rapidly. The method is characterized by high spatial resolution and large probing depth. We discuss data acquisition and 3D IP imaging procedures using the central gradient array with variable electrode distances. A 3D geoelectric model was constructed and then numerically modeled. The data modeling results suggest that this method can capture the features of real geoelectric models. The method was applied to a polymetallic mine in Gansu Province. The results suggest that IP 3D tomography captures the distribution of resistivity and polarization of subsurface media, delineating the extension of abrupt interfaces, and identifies mineralization.展开更多
Synthetic biology is an interdisciplinary field that takes top-down approaches to understand and engineer biological systems through design-build-test cycles. A number of advances in this relatively young field have g...Synthetic biology is an interdisciplinary field that takes top-down approaches to understand and engineer biological systems through design-build-test cycles. A number of advances in this relatively young field have greatly accelerated such engineering cycles. Specifically, various innovative tools were developed for in silico biosystems design, DNA de novo synthesis and assembly, construct verification, as well as metabolite analysis, which have laid a solid foundation for building biological foundries for rapid prototyping of improved or novel biosystems. This review summarizes the state-of-the-art technologies for synthetic biology and discusses the challenges to establish such biological foundries.展开更多
Composite Bi@Bi2O3 microspheres have been synthesized via a microwave-assisted solvothermal route. The Bi@Bi2O3 microspheres had a narrow size distribution in the range 1.2-2.8 mm. Glucose was selected as the reductan...Composite Bi@Bi2O3 microspheres have been synthesized via a microwave-assisted solvothermal route. The Bi@Bi2O3 microspheres had a narrow size distribution in the range 1.2-2.8 mm. Glucose was selected as the reductant, BiCl3 as the bismuth source, and ethylene glycol （EG） as the solvent in the synthesis system. The as-synthesized sample was characterized by X-ray diffraction （XRD）, Raman spectroscopy, X-ray photoelectron spectroscopy （XPS）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, particle diameter distribution, energy dispersive X-ray spectroscopy （EDS）, ultraviolet-visible （UV-vis） spectroscopy, and photoluminescence （PL） spectroscopy. The photocatalytic activities of the Bi@Bi2O3 microspheres were evaluated by the photodegradation of rhodamine B （RhB） and methyl orange （MO） dyes under UV light irradiation. The degradation reached -96.6% for RhB and 100% for MO after 4 h reaction in the presence of the as-synthesized Bi@Bi2O3 microspheres.展开更多
文摘二氧化碳(CO_2)资源化利用是近年来的一个研究热点,利用生物电化学系统还原CO_2生产能源物质是一种新兴技术.在微生物电合成系统(MES)中利用混合微生物富集阴极功能微生物,评估阴极电势对其还原CO_2产甲烷的影响.当阴极电势从-0.70 V降低到-0.90 V vs Ag/Ag Cl时,MES产甲烷的量和速率都在增加,最大的产甲烷量和速率分别达到了0.265 mol/m^2和0.025 mmol/h.与此同时,MES的电流密度从0.002 A/m^2增加到0.18 A/m^2,阴极产甲烷的库伦效率在49%和90%之间.当阴极电势更负时,MES阴极几乎不产甲烷.扫描电镜分析(SEM)表明,有多种不同形态的微生物吸附在阴极碳毡上,它们的形态主要呈杆状和球状.16S r DNA测序分析表明Methanobacterium是MES阴极生物膜上优势的产甲烷菌.本研究表明,微生物电合成系统还原CO_2产甲烷的阴极电势必须控制在适当的范围内,才能高效地还原CO_2产甲烷.
基金Supported by Grants from the United States National Institutes of Health (GM069338 and HL20948) awarded to Russell DW
文摘AIM: To investigate the clinical presentations associated with bile acid synthesis defects and to describe identification of individual disorders and diagnostic pitfalls. METHODS: We describe semiquantitative determination of 16 urinary bile acid metabolites by electrospray ionization-tandem mass spectrometry. Sample preparation was performed by solid-phase extraction. The total analysis time was 2 min per sample. We determined bile acid metabolites in 363 patients with suspected defects in bile acid metabolism. RESULTS: Abnormal bile acid metabolites were found in 36 patients. Two patients had bile acid synthesis defects but presented with atypical presentations. In 2 other patients who were later shown to be affected by biliary atresia and cystic fibrosis the profile of bile acid metabolites was initially suggestive of a bile acid synthesis defect. Three adult patients suffered from cerebrotendinous xanthomatosis. Nineteen patients had peroxisomal disorders, and 10 patients had cholestatic hepatopathy of other cause. CONCLUSION: Screening for urinary cholanoids should be done in every infant with cholestatic hepatopathy as well as in children with progressive neurological disease to provide specific therapy.
基金funded jointly by the National High Technology Research and Development Program(863 Program:No.2014AA06A610)special funds for basic scientific research business expenses of the Chinese Academy of Geological Sciences(No.YYWF201632)the National Major Scientific Instruments and Equipment Development Projects(No.2011YQ050060)
文摘Induced polarization （IP） 3D tomography with the similar central gradient array combines IP sounding and IP profiling to retrieve 3D resistivity and polarization data rapidly. The method is characterized by high spatial resolution and large probing depth. We discuss data acquisition and 3D IP imaging procedures using the central gradient array with variable electrode distances. A 3D geoelectric model was constructed and then numerically modeled. The data modeling results suggest that this method can capture the features of real geoelectric models. The method was applied to a polymetallic mine in Gansu Province. The results suggest that IP 3D tomography captures the distribution of resistivity and polarization of subsurface media, delineating the extension of abrupt interfaces, and identifies mineralization.
基金the National Institutes of Health(GM077596)the National Academies Keck Futures Initiative on Synthetic Biology,Defense Advanced Research Program Agency,Roy J.Carver Charitable TrustInstitute for Genomic Biology at the University of Illinois at Urbana-Champaign for financial support in our development and application of DNA assembly technologies
文摘Synthetic biology is an interdisciplinary field that takes top-down approaches to understand and engineer biological systems through design-build-test cycles. A number of advances in this relatively young field have greatly accelerated such engineering cycles. Specifically, various innovative tools were developed for in silico biosystems design, DNA de novo synthesis and assembly, construct verification, as well as metabolite analysis, which have laid a solid foundation for building biological foundries for rapid prototyping of improved or novel biosystems. This review summarizes the state-of-the-art technologies for synthetic biology and discusses the challenges to establish such biological foundries.
基金The financial supports Science Foundation of from the National Natural China （Nos. 20921001 and20535020）, the Innovation Method Fund of China （No 20081885189）, and the National High Technology Research and Development Program of China （No. 2009AA03Z321） are acknowledged.
文摘Composite Bi@Bi2O3 microspheres have been synthesized via a microwave-assisted solvothermal route. The Bi@Bi2O3 microspheres had a narrow size distribution in the range 1.2-2.8 mm. Glucose was selected as the reductant, BiCl3 as the bismuth source, and ethylene glycol （EG） as the solvent in the synthesis system. The as-synthesized sample was characterized by X-ray diffraction （XRD）, Raman spectroscopy, X-ray photoelectron spectroscopy （XPS）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, particle diameter distribution, energy dispersive X-ray spectroscopy （EDS）, ultraviolet-visible （UV-vis） spectroscopy, and photoluminescence （PL） spectroscopy. The photocatalytic activities of the Bi@Bi2O3 microspheres were evaluated by the photodegradation of rhodamine B （RhB） and methyl orange （MO） dyes under UV light irradiation. The degradation reached -96.6% for RhB and 100% for MO after 4 h reaction in the presence of the as-synthesized Bi@Bi2O3 microspheres.
