Active pixel sensor array for high spatio-temporal resolution electrophysiological recordings from single cell to large scale neuronal networks

Animal development is orchestrated by spatio-temporal gene expression programmes that drive precise lineage commitment, proliferation and migration events at the single-cell level, collectively leading to large-scale morphological change and functional specification in the whole organism. Efforts over decades have uncovered two ‘seemingly contradictory’ mechanisms in gene regulation governing these intricate processes: (i) stochasticity at individual gene regulatory steps in single cells and (ii) highly coordinated gene expression dynamics in the embryo. Here we discuss how these two layers of regulation arise from the molecular and the systems level, and how they might interplay to determine cell fate and to control the complex body plan. We also review recent technological advancements that enable quantitative analysis of gene regulation dynamics at single-cell, single-molecule resolution. These approaches outline next-generation experiments to decipher general principles bridging gaps between molecular dynamics in single cells and robust gene regulations in the embryo.

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Coded continuous wave meteor radar

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-8-7879-2015 ◽

2015 ◽

Vol 8 (7) ◽

pp. 7879-7907

Author(s):

J. Vierinen ◽

J. L. Chau ◽

N. Pfeffer ◽

M. Clahsen ◽

G. Stober

Keyword(s):

Temporal Resolution ◽

Large Scale ◽

Pulse Compression ◽

Continuous Wave ◽

Signal To Noise Ratio ◽

Field Measurements ◽

Meteor Radar ◽

Spatio Temporal ◽

To Receive ◽

Pulse Spacing

Abstract. The concept of coded continuous wave meteor radar is introduced. The radar uses a continuously transmitted pseudo-random waveform, which has several advantages: coding avoids range aliased echoes, which are often seen with commonly used pulsed specular meteor radars (SMRs); continuous transmissions maximize pulse compression gain, allowing operation with significantly lower peak transmit power; the temporal resolution can be changed after performing a measurement, as it does not depend on pulse spacing; and the low signal to noise ratio allows multiple geographically separated transmitters to be used in the same frequency band without significantly interfering with each other. The latter allows the same receiver antennas to be used to receive multiple transmitters. The principles of the signal processing are discussed, in addition to discussion of several practical ways to increase computation speed, and how to optimally detect meteor echoes. Measurements from a campaign performed with a coded continuous wave SMR are shown and compared with two standard pulsed SMR measurements. The type of meteor radar described in this paper would be suited for use in a large scale multi-static network of meteor radar transmitters and receivers. This would, for example, provide higher spatio-temporal resolution for mesospheric wind field measurements.

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Active Pixel Sensor Array for Digital X-ray Imaging in a-Si:H Technology

ECS Meeting Abstracts ◽

10.1149/ma2005-01/45/1758 ◽

2005 ◽

Keyword(s):

Sensor Array ◽

Active Pixel Sensor ◽

X Ray ◽

X Ray Imaging ◽

Active Pixel

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Current-mediated, current-reset 768×512 active pixel sensor array

1997 IEEE International Solids-State Circuits Conference. Digest of Technical Papers ◽

10.1109/isscc.1997.585325 ◽

2002 ◽

Cited By ~ 6

Author(s):

R.D. McGrath ◽

V.S. Clark ◽

P.K. Duane ◽

L.G. McIlrath ◽

W.D. Washkurak

Keyword(s):

Sensor Array ◽

Active Pixel Sensor ◽

Active Pixel

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Heavy ion transient characterization of a hardened-by-design active pixel sensor array

IEEE Radiation Effects Data Workshop ◽

10.1109/redw.2002.1045552 ◽

2003 ◽

Cited By ~ 9

Author(s):

C.J. Marshall ◽

K.A. LaBel ◽

R.A. Reed ◽

P.W. Marshall ◽

W.B. Byers ◽

...

Keyword(s):

Sensor Array ◽

Heavy Ion ◽

Active Pixel Sensor ◽

Active Pixel

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Threshold voltage shift compensated active pixel sensor array for digital X-ray imaging in a-Si technology

Electronics Letters ◽

10.1049/el:20058232 ◽

2005 ◽

Vol 41 (7) ◽

pp. 411 ◽

Cited By ~ 12

Author(s):

N. Safavian ◽

J. Lai ◽

J. Rowlands ◽

A. Nathan

Keyword(s):

Threshold Voltage ◽

Sensor Array ◽

Threshold Voltage Shift ◽

Voltage Shift ◽

Active Pixel Sensor ◽

X Ray ◽

X Ray Imaging ◽

Active Pixel

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A New Active 3D Optical Proximity Sensor Array and its Readout Circuit

ASME 2013 Conference on Information Storage and Processing Systems ◽

10.1115/isps2013-2888 ◽

2013 ◽

Cited By ~ 1

Author(s):

Paul C.-P. Chao ◽

Wei-Hsuan Hsu ◽

Che-Hung Tsai

Keyword(s):

Video Game ◽

Sensor Array ◽

Maximum Output ◽

Proximity Sensor ◽

Touch Panel ◽

Active Pixel Sensor ◽

Position Sensing ◽

Active Pixel ◽

Cmos Sensor ◽

Proximity Sensing

The products in the market are mostly 2D sensing. The touch panel technology is used in the industry and the video game wisely. Many of the ATMs, cell phones and the vending machines have touch panel technology in these years. The touch panel technology grows up quickly. In recent years, there has been increasing interests in proximity sensing technology [1–3]. This study proposes the 3D proximity sensing can be used in un-touch screen, a 3D keyboard, or constructed on the robot’s hand for sensing the distance and position of an object. As the optical components advance, the optical system, optical touch panel, object sensing and medical system are growing up with it. A photo detector is the part of the optical component. However, the photo detector transfers the photon to the current (photocurrent). This study needs a circuit to be the rear end of the photo detector, transferring the current to the voltage. An active pixel sensor is the viable way to realize the function. For the large area object sensing and high resolution, one pixel should be designed as small as possible. A small pixel however gives small photocurrent. The efficient way to transfer the photon to the voltage is important. The aim of this study is to develop a 3D-position sensing technique for an arbitrary object. The schematic for illustration is shown in Fig. 1. Different from conventional 2D capacitance or resistance touch panels, the proposed proximity sensor array has third axis sensing and the 3D sensing. A new active pixel circuit is proposed for realizing the sensor array. The active pixel sensor is used to convert the light to the voltage, and it can improve the resolution and reduce the noise. The standard and official active pixel sensor is a 3T-structure APS (or 3T-APS). The drawback of 3T-APS is that the output range is limited by the original circuit design. The maximum output cannot be up to bias voltage. The new APS resolution is better than the standard 3T-APS resolution in this aspect. It is a good improvement in terms of not only the CMOS sensor but also the 3D optical proximity sensing circuit.

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