Neural representations arise from high-dimensional population activity,but current neuromodulation methods lack the precision to write information into the central nervous system at this complexity.In this perspective...Neural representations arise from high-dimensional population activity,but current neuromodulation methods lack the precision to write information into the central nervous system at this complexity.In this perspective,we propose high-dimensional stimulation as an approach to better approximate natural neural codes for brain-machine interfaces.Key advancements in resolution,coverage,and safety are essential,with flexible microelectrode arrays offering a promising path toward precise synthetic neural codes.展开更多
An easy and practical system of feeble fluctuation of liquid electrical conductivity is described. The system, which increases a precision on the three orders magnitude as compared with that of the recent domestic con...An easy and practical system of feeble fluctuation of liquid electrical conductivity is described. The system, which increases a precision on the three orders magnitude as compared with that of the recent domestic conductivity meter, is used to measure the feeble fluctuation of the conductivity by means of compensation and comparison, so that it solves the problem of measuring the feeble fluctuation.展开更多
A new optical fiber fluoroptic thermometer based on the temperature—fluoroptic characteristic of fluoroptic materials is presented.The ratio technique of intensities of fluorescent emission lines of certain rare eart...A new optical fiber fluoroptic thermometer based on the temperature—fluoroptic characteristic of fluoroptic materials is presented.The ratio technique of intensities of fluorescent emission lines of certain rare earth phosphors is used,making the measurement of temperatures of the system to 0.5 ℃ precision. The characteristics of thermometer are discussed and the experiment results of temperature are given.展开更多
BeiDou regional navigation satellite system （BDS） also called BeiDou-2 has been in full operation since December 27, 2012. It consists of 14 satellites, including 5 satellites in Geostationary Orbit （GEO）, 5 satel...BeiDou regional navigation satellite system （BDS） also called BeiDou-2 has been in full operation since December 27, 2012. It consists of 14 satellites, including 5 satellites in Geostationary Orbit （GEO）, 5 satellites in Inclined Geosynchronous Orbit （IGSO）, and 4 satellites in Medium Earth Orbit （MEO）. In this paper, its basic navigation and positioning performance are evaluated preliminarily by the real data collected in Beijing, including satellite visibility, Position Dilution of Precision （PDOP） value, the precision of code and carrier phase measurements, the accuracy of single point positioning and differential position- ing and ambiguity resolution （AR） performance, which are also compared with those of GPS. It is shown that the precision of BDS code and carrier phase measurements are about 33 cm and 2 mm, respectively, which are comparable to those of GPS, and the accuracy of BDS single point positioning has satisfied the design requirement. The real-time kinematic positioning is also feasible by BDS alolae in the opening condition, since its fixed rate and reliability of single-epoch dual-frequency AR is comparable to those of GPS. The accuracy of BDS carrier phase differential positioning is better than 1 cm for a very short baseline of 4.2 m and 3 cm for a short baseline of 8.2 km, which is on the same level with that of GPS. For the combined BDS and GPS, the fixed rate and reliability of single-epoch AR and the positioning accuracy are improved significantly. The accu- racy of BDS/GPS carrier phase differential positioning is about 35 and 20 % better than that of GPS for two short baseline tests in this study. The accuracy of BDS code differential positioning is better than 2.5 m. However it is worse than that of GPS, which may result from large code multipath errors of BDS GEO satellite measurements.展开更多
Noncoding“junk DNA”,which constitutes 98%of our genome,is now generally considered to play a fundamental role in the precise regulation of coding genes to establish cell identity.One feature of functional“junk DNA...Noncoding“junk DNA”,which constitutes 98%of our genome,is now generally considered to play a fundamental role in the precise regulation of coding genes to establish cell identity.One feature of functional“junk DNA”is its accessibility.In cancer cells,aberrant chromatin accessibility is recognized as one of the major hallmarks.Understanding such events requires high-throughput screening,such as Assay for Transposase-Accessible Chromatin using sequencing(ATAC-seq),which generates large-scale data that are puzzling for biologists.However,existing web tools only support cell line data and lack high-quality clinical phenotypes or matched transcriptomes.Here,we developed Shiny Pan-cancer Accessible Chromatin Explorer(SPACE)as an all-in-one web server encompassing 562,709 regulatory elements in 404 patients across 23 cancer types.展开更多
基金funded by R01EY036094(L.L)R01NS102917(C.X)+1 种基金U01NS115588(C.X)U01NS131086(C.X&L.L.)。
文摘Neural representations arise from high-dimensional population activity,but current neuromodulation methods lack the precision to write information into the central nervous system at this complexity.In this perspective,we propose high-dimensional stimulation as an approach to better approximate natural neural codes for brain-machine interfaces.Key advancements in resolution,coverage,and safety are essential,with flexible microelectrode arrays offering a promising path toward precise synthetic neural codes.
文摘An easy and practical system of feeble fluctuation of liquid electrical conductivity is described. The system, which increases a precision on the three orders magnitude as compared with that of the recent domestic conductivity meter, is used to measure the feeble fluctuation of the conductivity by means of compensation and comparison, so that it solves the problem of measuring the feeble fluctuation.
文摘A new optical fiber fluoroptic thermometer based on the temperature—fluoroptic characteristic of fluoroptic materials is presented.The ratio technique of intensities of fluorescent emission lines of certain rare earth phosphors is used,making the measurement of temperatures of the system to 0.5 ℃ precision. The characteristics of thermometer are discussed and the experiment results of temperature are given.
基金sponsored by the National Natural Science Foundation of China(Grant Nos.41020144004,41374019,41104022)the National High Technology Research and Development Program of China(Grant No.2013AA122501)
文摘BeiDou regional navigation satellite system （BDS） also called BeiDou-2 has been in full operation since December 27, 2012. It consists of 14 satellites, including 5 satellites in Geostationary Orbit （GEO）, 5 satellites in Inclined Geosynchronous Orbit （IGSO）, and 4 satellites in Medium Earth Orbit （MEO）. In this paper, its basic navigation and positioning performance are evaluated preliminarily by the real data collected in Beijing, including satellite visibility, Position Dilution of Precision （PDOP） value, the precision of code and carrier phase measurements, the accuracy of single point positioning and differential position- ing and ambiguity resolution （AR） performance, which are also compared with those of GPS. It is shown that the precision of BDS code and carrier phase measurements are about 33 cm and 2 mm, respectively, which are comparable to those of GPS, and the accuracy of BDS single point positioning has satisfied the design requirement. The real-time kinematic positioning is also feasible by BDS alolae in the opening condition, since its fixed rate and reliability of single-epoch dual-frequency AR is comparable to those of GPS. The accuracy of BDS carrier phase differential positioning is better than 1 cm for a very short baseline of 4.2 m and 3 cm for a short baseline of 8.2 km, which is on the same level with that of GPS. For the combined BDS and GPS, the fixed rate and reliability of single-epoch AR and the positioning accuracy are improved significantly. The accu- racy of BDS/GPS carrier phase differential positioning is about 35 and 20 % better than that of GPS for two short baseline tests in this study. The accuracy of BDS code differential positioning is better than 2.5 m. However it is worse than that of GPS, which may result from large code multipath errors of BDS GEO satellite measurements.
基金supported by the National Natural Science Foundation of China(31770935,81873531,31970616)the Distinguished Professorship Program of Jiangsu Province to YF+2 种基金the Distinguished Professorship Program of Jiangsu Province to RMthe National Undergraduate Training Programs for Innovation(201710304030Z)the National Undergraduate Training Programs for Innovation(201810304026Z).
文摘Noncoding“junk DNA”,which constitutes 98%of our genome,is now generally considered to play a fundamental role in the precise regulation of coding genes to establish cell identity.One feature of functional“junk DNA”is its accessibility.In cancer cells,aberrant chromatin accessibility is recognized as one of the major hallmarks.Understanding such events requires high-throughput screening,such as Assay for Transposase-Accessible Chromatin using sequencing(ATAC-seq),which generates large-scale data that are puzzling for biologists.However,existing web tools only support cell line data and lack high-quality clinical phenotypes or matched transcriptomes.Here,we developed Shiny Pan-cancer Accessible Chromatin Explorer(SPACE)as an all-in-one web server encompassing 562,709 regulatory elements in 404 patients across 23 cancer types.
