A serious sandstorm occurred in North China from April 5 to April 7, 2000, while the remote smallsand decending took place in even larger area to the far northeast China. In Chanchun city, smallsand descending with sn...A serious sandstorm occurred in North China from April 5 to April 7, 2000, while the remote smallsand decending took place in even larger area to the far northeast China. In Chanchun city, smallsand descending with snow provides the best samples to conduct a quantitative research on the possible impacts of city - ecology. In the 253km2 urban district area of Changchun city, smallsands accumulated up to more than 3000t on April 7, according to the calculation of four "mud - snow" samples. After naturally melting in room temperature, two samples are taken to do quarantine of "invasion bacteria". As a preliminary result, the individual amount of bacterium in 1 ml sample water is up to 8. 9 x 104 or 1. 05 x 105, and it is estimated that there are 640 million "invasion bacterium" individuals in one square meter. This study proves that other than the obvious environmental effects of sandstorm, the urban micro - ecosystem is very possible under threat by the "invasion bacterium" accompanied by remote descending smallsand.展开更多
This paper presents a multi-interface embedded server architecture for remote real-time monitoring system and distributed monitoring applications. In the scheme,an embedded microprocessor( LPC3250 from NXP) is chosen ...This paper presents a multi-interface embedded server architecture for remote real-time monitoring system and distributed monitoring applications. In the scheme,an embedded microprocessor( LPC3250 from NXP) is chosen as the CPU of the embedded server with a linux operation system( OS) environment. The embedded server provides multiple interfaces for supporting various application scenarios. The whole network is based on local area network and adopts the Browser / Server( B / S) model. The monitoring and control node is as a browser endpoint and the remote node with an embedded server is as a server endpoint. Users can easily acquire various sensors information through writing Internet protocol address of remote node on the computer browser. Compared with client / server( C / S) mode,B / S model needs less maintain and can be applicable to large user group. In addition,a simple network management protocol( SNMP) is used for management of devices in Internet protocol( IP) networks. The results of the demonstration experiment show that the proposed system gives good support to manage the network from different user terminals and allows the users to better interact with the ambient environment.展开更多
Drones of various shapes, sizes, and functionalities have emerged over the past few decades, and their civilian applications are becoming increasingly appealing. Flexible, low-cost, and high-resolution remote sensing ...Drones of various shapes, sizes, and functionalities have emerged over the past few decades, and their civilian applications are becoming increasingly appealing. Flexible, low-cost, and high-resolution remote sensing systems that use drones as platforms are important for filling data gaps and supplementing the capabilities of crewed/manned aircraft and satellite remote sensing systems. Here, we refer to this growing remote sensing ini- tiative as drone remote sensing and explain its unique advantages in forestry research and practices. Furthermore, we summarize the various approaches of drone remote sensing to surveying forests, mapping canopy gaps, mea- suring forest canopy height, tracking forest wildfires, and supporting intensive forest management. The benefits of drone remote sensing include low material and operational costs, flexible control of spatial and temporal resolution, high-intensity data collection, and the absence of risk to crews. The current forestry applications of drone remote sensing are still at an experimental stage, but they are expected to expand rapidly. To better guide the development of drone remote sensing for sustainable forestry, it isimportant to systematically and continuously conduct comparative studies to determine the appropriate drone remote sensing technologies for various forest conditions and/or forestry applications.展开更多
Considering the need of target positioning,a remote positioning system is designed based on global positioning system(GPS)and general packet radio service(GPRS);The data collection terminal is based on microcontroller...Considering the need of target positioning,a remote positioning system is designed based on global positioning system(GPS)and general packet radio service(GPRS);The data collection terminal is based on microcontroller unit(MCU)PIC24FV301.It uses GPRS network to create wireless link and transmits GPS source information which is collected by LEA-5H board to monitor center on the Internet.The monitor center obtains the target information through processing and analysis of the calculated data.Actual operation results indicate that the designed system has excellent performance and achieves the goal of the remote location.展开更多
Current neuromodulation techniques such as optogenetics and deep-brain stimulation are transforming basic and translational neuroscience. These two neuro- modulation approaches are, however, invasive since surgical im...Current neuromodulation techniques such as optogenetics and deep-brain stimulation are transforming basic and translational neuroscience. These two neuro- modulation approaches are, however, invasive since surgical implantation of an optical fiber or wire electrode is required. Here, we have invented a non-invasive magnetogenetics that combines the genetic targeting of a mag- netoreceptor with remote magnetic stimulation. The noninvasive activation of neurons was achieved by neuronal expression of an exogenous magnetoreceptor, an iron-sulfur cluster assembly protein 1 （Iscal）. In HEK-293 cells and cultured hippocampal neurons expressing this magnetoreceptor, application of an external magnetic field resulted in membrane depolarization and calcium influx in a reproducible and reversible manner, as indicated by the ultrasensitive fluorescent calcium indicator GCaMP6s.Moreover, the magnetogenetic control of neuronal activity might be dependent on the direction of the magnetic field and exhibits on-response and off-response patterns for the external magnetic field applied. The activation of this magnetoreceptor can depolarize neurons and elicit trains of action potentials, which can be triggered repetitively with a remote magnetic field in whole-cell patch-clamp recording. In transgenic Caenorhabditis elegans expressing this magnetoreceptor in myo-3-specific muscle cells or mec-4- specific neurons, application of the external magnetic field triggered muscle contraction and withdrawal behavior of the worms, indicative of magnet-dependent activation of muscle cells and touch receptor neurons, respectively. The advantages of magnetogenetics over optogenetics are its exclusive non-invasive, deep penetration, long-term continuous dosing, unlimited accessibility, spatial uniformity and relative safety. Like optogenetics that has gone through decade-long improvements, magnetogenetics, with continuous modification and maturation, will reshape the current landscape of neuromodulation toolboxes and will have a broad range of applications to basic and translational neuroscience as well as other biological sciences. We envision a new age of magnetogenetics is coming.展开更多
特殊目的载体SPV(Special Purpose V eh icle)是资产证券化(ABS)交易架构中最具特色的结构设计。文章的目的就在于探究符合我国国情的SPV的架构方案。文章在分析了SPV的几种可选模式及我国的法律障碍后,提出了我国资产证券化中SPV的四...特殊目的载体SPV(Special Purpose V eh icle)是资产证券化(ABS)交易架构中最具特色的结构设计。文章的目的就在于探究符合我国国情的SPV的架构方案。文章在分析了SPV的几种可选模式及我国的法律障碍后,提出了我国资产证券化中SPV的四种较为可行的方案,并以个人住房抵押贷款、商业银行不良贷款等资产作为突破口,详细地提出了架构住房抵押贷款证券化机构和银行不良资产证券化机构的具体方案。展开更多
2007年3月5日美国次级按揭住房贷款专业机构新世纪金融(New Century Financial Corp.)遭遇了"黑色星期一",短短数月新世纪金融破产,三十余家次级抵押贷款公司停业,多家大幅持有次级按揭贷款债券的基金破产。次级债危机开始由...2007年3月5日美国次级按揭住房贷款专业机构新世纪金融(New Century Financial Corp.)遭遇了"黑色星期一",短短数月新世纪金融破产,三十余家次级抵押贷款公司停业,多家大幅持有次级按揭贷款债券的基金破产。次级债危机开始由美国向全球扩散并波及全球股市。在这个金融风波中,次级债危机原因在哪里?本文分析了次级债危机的形成原因及我国才起步的住房抵押贷款支持证券中的法律问题,提出相关的改进建议。展开更多
文摘A serious sandstorm occurred in North China from April 5 to April 7, 2000, while the remote smallsand decending took place in even larger area to the far northeast China. In Chanchun city, smallsand descending with snow provides the best samples to conduct a quantitative research on the possible impacts of city - ecology. In the 253km2 urban district area of Changchun city, smallsands accumulated up to more than 3000t on April 7, according to the calculation of four "mud - snow" samples. After naturally melting in room temperature, two samples are taken to do quarantine of "invasion bacteria". As a preliminary result, the individual amount of bacterium in 1 ml sample water is up to 8. 9 x 104 or 1. 05 x 105, and it is estimated that there are 640 million "invasion bacterium" individuals in one square meter. This study proves that other than the obvious environmental effects of sandstorm, the urban micro - ecosystem is very possible under threat by the "invasion bacterium" accompanied by remote descending smallsand.
基金Sponsored by the National High Technology Research and Development Program(Grant No.2012AA02A604)
文摘This paper presents a multi-interface embedded server architecture for remote real-time monitoring system and distributed monitoring applications. In the scheme,an embedded microprocessor( LPC3250 from NXP) is chosen as the CPU of the embedded server with a linux operation system( OS) environment. The embedded server provides multiple interfaces for supporting various application scenarios. The whole network is based on local area network and adopts the Browser / Server( B / S) model. The monitoring and control node is as a browser endpoint and the remote node with an embedded server is as a server endpoint. Users can easily acquire various sensors information through writing Internet protocol address of remote node on the computer browser. Compared with client / server( C / S) mode,B / S model needs less maintain and can be applicable to large user group. In addition,a simple network management protocol( SNMP) is used for management of devices in Internet protocol( IP) networks. The results of the demonstration experiment show that the proposed system gives good support to manage the network from different user terminals and allows the users to better interact with the ambient environment.
文摘Drones of various shapes, sizes, and functionalities have emerged over the past few decades, and their civilian applications are becoming increasingly appealing. Flexible, low-cost, and high-resolution remote sensing systems that use drones as platforms are important for filling data gaps and supplementing the capabilities of crewed/manned aircraft and satellite remote sensing systems. Here, we refer to this growing remote sensing ini- tiative as drone remote sensing and explain its unique advantages in forestry research and practices. Furthermore, we summarize the various approaches of drone remote sensing to surveying forests, mapping canopy gaps, mea- suring forest canopy height, tracking forest wildfires, and supporting intensive forest management. The benefits of drone remote sensing include low material and operational costs, flexible control of spatial and temporal resolution, high-intensity data collection, and the absence of risk to crews. The current forestry applications of drone remote sensing are still at an experimental stage, but they are expected to expand rapidly. To better guide the development of drone remote sensing for sustainable forestry, it isimportant to systematically and continuously conduct comparative studies to determine the appropriate drone remote sensing technologies for various forest conditions and/or forestry applications.
文摘Considering the need of target positioning,a remote positioning system is designed based on global positioning system(GPS)and general packet radio service(GPRS);The data collection terminal is based on microcontroller unit(MCU)PIC24FV301.It uses GPRS network to create wireless link and transmits GPS source information which is collected by LEA-5H board to monitor center on the Internet.The monitor center obtains the target information through processing and analysis of the calculated data.Actual operation results indicate that the designed system has excellent performance and achieves the goal of the remote location.
基金supported by Tsinghua-Peking Center for Life SciencesIDG/Mc Govern Foundationthe National Natural Science Foundation of China
文摘Current neuromodulation techniques such as optogenetics and deep-brain stimulation are transforming basic and translational neuroscience. These two neuro- modulation approaches are, however, invasive since surgical implantation of an optical fiber or wire electrode is required. Here, we have invented a non-invasive magnetogenetics that combines the genetic targeting of a mag- netoreceptor with remote magnetic stimulation. The noninvasive activation of neurons was achieved by neuronal expression of an exogenous magnetoreceptor, an iron-sulfur cluster assembly protein 1 （Iscal）. In HEK-293 cells and cultured hippocampal neurons expressing this magnetoreceptor, application of an external magnetic field resulted in membrane depolarization and calcium influx in a reproducible and reversible manner, as indicated by the ultrasensitive fluorescent calcium indicator GCaMP6s.Moreover, the magnetogenetic control of neuronal activity might be dependent on the direction of the magnetic field and exhibits on-response and off-response patterns for the external magnetic field applied. The activation of this magnetoreceptor can depolarize neurons and elicit trains of action potentials, which can be triggered repetitively with a remote magnetic field in whole-cell patch-clamp recording. In transgenic Caenorhabditis elegans expressing this magnetoreceptor in myo-3-specific muscle cells or mec-4- specific neurons, application of the external magnetic field triggered muscle contraction and withdrawal behavior of the worms, indicative of magnet-dependent activation of muscle cells and touch receptor neurons, respectively. The advantages of magnetogenetics over optogenetics are its exclusive non-invasive, deep penetration, long-term continuous dosing, unlimited accessibility, spatial uniformity and relative safety. Like optogenetics that has gone through decade-long improvements, magnetogenetics, with continuous modification and maturation, will reshape the current landscape of neuromodulation toolboxes and will have a broad range of applications to basic and translational neuroscience as well as other biological sciences. We envision a new age of magnetogenetics is coming.
文摘特殊目的载体SPV(Special Purpose V eh icle)是资产证券化(ABS)交易架构中最具特色的结构设计。文章的目的就在于探究符合我国国情的SPV的架构方案。文章在分析了SPV的几种可选模式及我国的法律障碍后,提出了我国资产证券化中SPV的四种较为可行的方案,并以个人住房抵押贷款、商业银行不良贷款等资产作为突破口,详细地提出了架构住房抵押贷款证券化机构和银行不良资产证券化机构的具体方案。
文摘2007年3月5日美国次级按揭住房贷款专业机构新世纪金融(New Century Financial Corp.)遭遇了"黑色星期一",短短数月新世纪金融破产,三十余家次级抵押贷款公司停业,多家大幅持有次级按揭贷款债券的基金破产。次级债危机开始由美国向全球扩散并波及全球股市。在这个金融风波中,次级债危机原因在哪里?本文分析了次级债危机的形成原因及我国才起步的住房抵押贷款支持证券中的法律问题,提出相关的改进建议。
