The transports of the dynamic biochemical signals in the non-reversing pulsatile flows in the mixing microchannel of a Y-shaped microfluidic device are ana- lyzed. The results show that the mixing micro-channel acts a...The transports of the dynamic biochemical signals in the non-reversing pulsatile flows in the mixing microchannel of a Y-shaped microfluidic device are ana- lyzed. The results show that the mixing micro-channel acts as a low-pass filter, and the biochemical signals are nonlinearly modulated by the pulsatile flows, which depend on the biochemical signal frequency, the flow signal frequency, and the biochemical signal transporting distance. It is concluded that, the transfer characteristics of the dynamic biochemical signals, which are transported in the time-varying flows, should be carefully considered for better loading biochemical signals on the cells cultured on the bottom of the microfluidic channel.展开更多
A high-precision shape detecting system of cold rolling strip is developed to meet industrial application, which mainly consists of the shape detecting roller, the collecting ring, the digital signal processing （DSP...A high-precision shape detecting system of cold rolling strip is developed to meet industrial application, which mainly consists of the shape detecting roller, the collecting ring, the digital signal processing （DSP） shape signal processing board and the shape control model. Based on the shape detecting principle, the shape detecting roller is designed with a new integral structure for improving the precision of shape detecting and avoiding scratching strip surface. Based on the DSP technology, the DSP shape signal processing circuit board is designed and embedded in the shape detecting system for the reliability and stability of shape signal processing. The shape detecting system was successfully used in Angang 1 250 mm HC 6-high reversible cold rolling mill. The precision of shape detecting is 0.2 I and the shape deviation is controlled within 6 1 after the close loop shape control is input.展开更多
Pulse shaping,which improves signal-to-noise ratio excellently,has been extensively used in nuclear signal processing.This paper presents a cusp-like pulse-shaping technique developed through the recursive difference ...Pulse shaping,which improves signal-to-noise ratio excellently,has been extensively used in nuclear signal processing.This paper presents a cusp-like pulse-shaping technique developed through the recursive difference equation in time domain.It can be implemented in field programmable gate array hardware system.Another flat-topped cusp-like shaper is developed to optimize the time constant of pulse shaping and reduce the influence of ballistic deficit.The methods of both baseline restoration and pile-up rejection are described.The ^(137)Cs energy spectra measured with the digital cusp-like shaper are 6.6% energy resolution,while those by traditional analog pulse shaper are 7.2% energy resolution,under the same conditions.This technique offers flexibility,too,in adjusting the pulse shaper parameters.展开更多
水稻是最重要的粮食作物之一,其产量对世界粮食安全影响巨大。提高水稻的产量是育种的永恒主题,也是解决全球人口迅速增长和耕地面积持续下降矛盾的迫切需求。水稻粒型是决定其单株产量的主要因素之一,是受多基因控制的能够稳定遗传的...水稻是最重要的粮食作物之一,其产量对世界粮食安全影响巨大。提高水稻的产量是育种的永恒主题,也是解决全球人口迅速增长和耕地面积持续下降矛盾的迫切需求。水稻粒型是决定其单株产量的主要因素之一,是受多基因控制的能够稳定遗传的数量性状,由籽粒的粒长、粒宽和粒厚共同决定。籽粒大小由调控母体组织和合子的信号协同控制,与颖壳细胞的增殖和扩张、胚乳的生长发育密切相关。近年来,基于图位克隆和全基因组关联分析技术的发展,对粒型调控机制的的遗传研究逐步深入。大量粒型相关数量性状位点(quantitative trait locus,QTL)被确定,许多粒型相关基因被克隆并进行了功能解析,这些基因大多表现为一因多效,与其他粒型基因共同协调表达,进而构成调控网络。鉴定和解析水稻粒型调控的遗传和分子机制,能为水稻分子设计育种提供新的思路。本文从胚乳发育和颖壳发育视角,概述了水稻籽粒发育的基本过程,以及粒型相关QTL的研究现状,聚焦于近来取得较大进展的G蛋白信号通路、促分裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)级联、泛素-蛋白酶体途径以及miRNA相关通路在水稻粒型调控中的功能,梳理了水稻粒型调控分子网络,并就水稻粒型遗传研究中的前景和存在的主要问题进行了展望和分析,旨在为水稻的定向遗传改良和分子设计育种研究提供参考。展开更多
基金Project supported by the National Natural Science Foundation of China(Nos.11172060 and11672065)
文摘The transports of the dynamic biochemical signals in the non-reversing pulsatile flows in the mixing microchannel of a Y-shaped microfluidic device are ana- lyzed. The results show that the mixing micro-channel acts as a low-pass filter, and the biochemical signals are nonlinearly modulated by the pulsatile flows, which depend on the biochemical signal frequency, the flow signal frequency, and the biochemical signal transporting distance. It is concluded that, the transfer characteristics of the dynamic biochemical signals, which are transported in the time-varying flows, should be carefully considered for better loading biochemical signals on the cells cultured on the bottom of the microfluidic channel.
基金Foundation item: Project(2009AA04Z143) supported by the National High Technology Research and Development Program of ChinaProject (E2011203004) supported by Natural Science Foundation of Hebei Province, ChinaProjects(2011BAF15B03, 2011BAF15B02) supported by the National Science Plan of China
文摘A high-precision shape detecting system of cold rolling strip is developed to meet industrial application, which mainly consists of the shape detecting roller, the collecting ring, the digital signal processing （DSP） shape signal processing board and the shape control model. Based on the shape detecting principle, the shape detecting roller is designed with a new integral structure for improving the precision of shape detecting and avoiding scratching strip surface. Based on the DSP technology, the DSP shape signal processing circuit board is designed and embedded in the shape detecting system for the reliability and stability of shape signal processing. The shape detecting system was successfully used in Angang 1 250 mm HC 6-high reversible cold rolling mill. The precision of shape detecting is 0.2 I and the shape deviation is controlled within 6 1 after the close loop shape control is input.
基金supported by the National Natural Science Foundation of China(Nos.41474159 and 41504139)Sichuan Youth Science and Technology Foundation(No.2015JQ0035)+1 种基金Sichuan Science and Technology Support Program(No.2017GZ0390)the Key Laboratory of Applied Nuclear Techniques in Geosciences Sichuan(No.gnzds2014006)
文摘Pulse shaping,which improves signal-to-noise ratio excellently,has been extensively used in nuclear signal processing.This paper presents a cusp-like pulse-shaping technique developed through the recursive difference equation in time domain.It can be implemented in field programmable gate array hardware system.Another flat-topped cusp-like shaper is developed to optimize the time constant of pulse shaping and reduce the influence of ballistic deficit.The methods of both baseline restoration and pile-up rejection are described.The ^(137)Cs energy spectra measured with the digital cusp-like shaper are 6.6% energy resolution,while those by traditional analog pulse shaper are 7.2% energy resolution,under the same conditions.This technique offers flexibility,too,in adjusting the pulse shaper parameters.
文摘水稻是最重要的粮食作物之一,其产量对世界粮食安全影响巨大。提高水稻的产量是育种的永恒主题,也是解决全球人口迅速增长和耕地面积持续下降矛盾的迫切需求。水稻粒型是决定其单株产量的主要因素之一,是受多基因控制的能够稳定遗传的数量性状,由籽粒的粒长、粒宽和粒厚共同决定。籽粒大小由调控母体组织和合子的信号协同控制,与颖壳细胞的增殖和扩张、胚乳的生长发育密切相关。近年来,基于图位克隆和全基因组关联分析技术的发展,对粒型调控机制的的遗传研究逐步深入。大量粒型相关数量性状位点(quantitative trait locus,QTL)被确定,许多粒型相关基因被克隆并进行了功能解析,这些基因大多表现为一因多效,与其他粒型基因共同协调表达,进而构成调控网络。鉴定和解析水稻粒型调控的遗传和分子机制,能为水稻分子设计育种提供新的思路。本文从胚乳发育和颖壳发育视角,概述了水稻籽粒发育的基本过程,以及粒型相关QTL的研究现状,聚焦于近来取得较大进展的G蛋白信号通路、促分裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)级联、泛素-蛋白酶体途径以及miRNA相关通路在水稻粒型调控中的功能,梳理了水稻粒型调控分子网络,并就水稻粒型遗传研究中的前景和存在的主要问题进行了展望和分析,旨在为水稻的定向遗传改良和分子设计育种研究提供参考。
