Microsensor measurements and fluorescence in situ hybridization （FISH） analysis were combined to investigate the microbial populations and activities in a laboratory-scale sequencing batch reactor （SBR） for comple...Microsensor measurements and fluorescence in situ hybridization （FISH） analysis were combined to investigate the microbial populations and activities in a laboratory-scale sequencing batch reactor （SBR） for completely autotrophic nitrogen removal over nitrite （CANON）. Fed with synthetic wastewater rich in ammo- nia, the SBR removed 82.54-5.4% ofinfluent nitrogen and a maximum nitrogen-removal rate of 0.52kgN.m 3.d-l was achieved. The FISH analysis revealed that aerobic ammonium-oxidizing bacteria （AerAOB） Nitrosomonas and anaerobic ammonium-oxidizing bacteria （AnAOB） dominated the community. To quantify the microbial activities inside the sludge aggregates, microprofiles were measured using pH, dissolved oxygen （DO）, NH＋, NO＋ and NO3 microelectrodes. In the outer layer of sludge aggregates （0-700 μm）, nitrite-oxidizing bacteria （NOB） showed high activity with 4.1 gmol-cm3＋ h-1 of maximum nitrate production rate under the condition of DO concentration higher than 3.3 mg. L 1. Maximum AerAOB activity was detected in the middle layer （depths around 1700 μm） where DO concentration was 1.1 μg. L-1. In the inner layer （2200-3500μm）, where DO concentration was below 0.9 mg. L-1, AnAOB activity was detected. We thus showed that information obtained from microscopic views can be helpful in optimizing the SBR performance.展开更多
Inoculated with conventional anaerobic activated sludge, the Anammox process was successfully developed in an anaerobic rotating biological contactor （AnRBC） fed with a low ratio of CfN synthetic wastewater. Operate...Inoculated with conventional anaerobic activated sludge, the Anammox process was successfully developed in an anaerobic rotating biological contactor （AnRBC） fed with a low ratio of CfN synthetic wastewater. Operated in a single point feed mode, the AnRBC removed 92.1% （n = 126） of the influent N at the highest surface load of 12 g/（m2.day）. The biomass increased by 25% and 17.1 g/（m2·day） of maximum N removal surface load was achieved by elevating flow rate with another feed point. Fluorescence in situ hybridization and polymerase chain reaction analysis indicated that the Anammox genus Candidatus Kuenenia stuttgartiensis dominated the community. Both Anammox and denitrifying activity were detected in biofilm by the application of microelectrodes. In the outer layer of the biofilm （0-2500 μm）, nitrite and ammonium consumed simultaneously in a ratio of 1.12/1, revealing the occurrence of Anammox. In the inner layer （〉 2500 μm）, a decrease of nitrate was caused by denitrification in the absence of nitrite and ammonium.展开更多
SIET(self-referencing ion electrode technique,自参考离子选择性电极技术)是电生理学研究的新手段,可以在植物抗逆研究中无损地获得植物细胞、组织、器官微区内离子流动态变化信息,而离子选择性微电极的制备及性能测试的标准化是SIE...SIET(self-referencing ion electrode technique,自参考离子选择性电极技术)是电生理学研究的新手段,可以在植物抗逆研究中无损地获得植物细胞、组织、器官微区内离子流动态变化信息,而离子选择性微电极的制备及性能测试的标准化是SIET系统对植物活细胞、活体组织原位离子流测试的前提。该文以钾离子选择性微电极为例,详细讨论了离子选择性微电极的拉制、硅烷化、灌充等制备过程,研究了微电极内阻等电极参数的测量方法,测试了微电极的能斯特响应斜率、检测范围、响应时间等参数,讨论了制备过程中微电极性能的影响因素。离子选择性微电极使用WD-2型微电极拉制仪由无导液丝的TW150-3型硼硅酸盐玻璃毛细管拉制成形,其尖端直径为1～9μm,干燥后用5%硅烷试剂在150℃温度下做硅烷化处理,再灌充入内充液与LIX(liquid ion exchanger,液态离子交换剂)而制成。研究表明:LIX成分是影响微电极内阻的重要因素,灌充LIX后的钾离子选择微电极(LIX长度为150～210μm)内阻达到108～109Ω,明显高于灌充LIX前;微电极在0.01～500mmol/L K+浓度范围内具有很好的线性关系,R2=0.9998,能斯特斜率为53.095mV/dec;微电极对1和100mmol/L KCl溶液的平均响应时间t95%小于1s。研究结果表明,离子选择性玻璃微电极的制备过程是影响微电极性能的关键,微电极尖端尺寸、内阻、响应时间等参数对微电极的应用影响显著。该研究可为离子选择性微电极的制备及其在SIET系统中的应用提供参考。展开更多
Mapping brain activity has received growing worldwide interest because it is expected to improve disease treatment and allow for the development of important neuromorphic computational methods.MEMS and microsystems ar...Mapping brain activity has received growing worldwide interest because it is expected to improve disease treatment and allow for the development of important neuromorphic computational methods.MEMS and microsystems are expected to continue to offer new and exciting solutions to meet the need for high-density,high-fidelity neural interfaces.Herein,the state-of-the-art in recording and stimulation tools for brain research is reviewed,and some of the most significant technology trends shaping the field of neurotechnology are discussed.展开更多
基金This work was supported by the National Natural Science Foundation of China （Grant No. 51108367）, Specialized Research Fund for the Doctoral Program of Higher Education （No. 20116120120009）, Natural Science Foundation of Shaanxi Province （No. 2014JQ7243） and innovative research team of Xi＇an University of Architecture and Technology.
文摘Microsensor measurements and fluorescence in situ hybridization （FISH） analysis were combined to investigate the microbial populations and activities in a laboratory-scale sequencing batch reactor （SBR） for completely autotrophic nitrogen removal over nitrite （CANON）. Fed with synthetic wastewater rich in ammo- nia, the SBR removed 82.54-5.4% ofinfluent nitrogen and a maximum nitrogen-removal rate of 0.52kgN.m 3.d-l was achieved. The FISH analysis revealed that aerobic ammonium-oxidizing bacteria （AerAOB） Nitrosomonas and anaerobic ammonium-oxidizing bacteria （AnAOB） dominated the community. To quantify the microbial activities inside the sludge aggregates, microprofiles were measured using pH, dissolved oxygen （DO）, NH＋, NO＋ and NO3 microelectrodes. In the outer layer of sludge aggregates （0-700 μm）, nitrite-oxidizing bacteria （NOB） showed high activity with 4.1 gmol-cm3＋ h-1 of maximum nitrate production rate under the condition of DO concentration higher than 3.3 mg. L 1. Maximum AerAOB activity was detected in the middle layer （depths around 1700 μm） where DO concentration was 1.1 μg. L-1. In the inner layer （2200-3500μm）, where DO concentration was below 0.9 mg. L-1, AnAOB activity was detected. We thus showed that information obtained from microscopic views can be helpful in optimizing the SBR performance.
基金supported by the Program for Changjiang Scholars and Innovative Research Team in University (No. IRT0853)the State Commission of Science Technology of China (No. 2009ZX07212-002)+3 种基金the National Natural Science Foundation of China (No. 51108367)the State Key Laboratory of Western Architecture and Technology (No. 10KF08)the Provincial Key Laboratory Projects of Environmental Engineering of Education Department of Shaanxi Province (No. 2010JS028)the Foundation of Shaanxi Educational Committee (No. 11JK0759)
文摘Inoculated with conventional anaerobic activated sludge, the Anammox process was successfully developed in an anaerobic rotating biological contactor （AnRBC） fed with a low ratio of CfN synthetic wastewater. Operated in a single point feed mode, the AnRBC removed 92.1% （n = 126） of the influent N at the highest surface load of 12 g/（m2.day）. The biomass increased by 25% and 17.1 g/（m2·day） of maximum N removal surface load was achieved by elevating flow rate with another feed point. Fluorescence in situ hybridization and polymerase chain reaction analysis indicated that the Anammox genus Candidatus Kuenenia stuttgartiensis dominated the community. Both Anammox and denitrifying activity were detected in biofilm by the application of microelectrodes. In the outer layer of the biofilm （0-2500 μm）, nitrite and ammonium consumed simultaneously in a ratio of 1.12/1, revealing the occurrence of Anammox. In the inner layer （〉 2500 μm）, a decrease of nitrate was caused by denitrification in the absence of nitrite and ammonium.
文摘SIET(self-referencing ion electrode technique,自参考离子选择性电极技术)是电生理学研究的新手段,可以在植物抗逆研究中无损地获得植物细胞、组织、器官微区内离子流动态变化信息,而离子选择性微电极的制备及性能测试的标准化是SIET系统对植物活细胞、活体组织原位离子流测试的前提。该文以钾离子选择性微电极为例,详细讨论了离子选择性微电极的拉制、硅烷化、灌充等制备过程,研究了微电极内阻等电极参数的测量方法,测试了微电极的能斯特响应斜率、检测范围、响应时间等参数,讨论了制备过程中微电极性能的影响因素。离子选择性微电极使用WD-2型微电极拉制仪由无导液丝的TW150-3型硼硅酸盐玻璃毛细管拉制成形,其尖端直径为1～9μm,干燥后用5%硅烷试剂在150℃温度下做硅烷化处理,再灌充入内充液与LIX(liquid ion exchanger,液态离子交换剂)而制成。研究表明:LIX成分是影响微电极内阻的重要因素,灌充LIX后的钾离子选择微电极(LIX长度为150～210μm)内阻达到108～109Ω,明显高于灌充LIX前;微电极在0.01～500mmol/L K+浓度范围内具有很好的线性关系,R2=0.9998,能斯特斜率为53.095mV/dec;微电极对1和100mmol/L KCl溶液的平均响应时间t95%小于1s。研究结果表明,离子选择性玻璃微电极的制备过程是影响微电极性能的关键,微电极尖端尺寸、内阻、响应时间等参数对微电极的应用影响显著。该研究可为离子选择性微电极的制备及其在SIET系统中的应用提供参考。
基金We gratefully acknowledge funding from the NIH(U01-NS090526-01,R21-EB-019221-01)the NSF(1545858).
文摘Mapping brain activity has received growing worldwide interest because it is expected to improve disease treatment and allow for the development of important neuromorphic computational methods.MEMS and microsystems are expected to continue to offer new and exciting solutions to meet the need for high-density,high-fidelity neural interfaces.Herein,the state-of-the-art in recording and stimulation tools for brain research is reviewed,and some of the most significant technology trends shaping the field of neurotechnology are discussed.
