Tomato: a crop species amenable to improvement by cellular and molecular methods

Tomato is a crop plant with a relatively small DNA content per haploid genome and a well developed genetics. Plant regeneration from explants and protoplasts is feasable which led to the development of efficient transformation procedures. In view of the current data, the isolation of useful mutants at the cellular level probably will be of limited value in the genetic improvement of tomato. Protoplast fusion may lead to novel combinations of organelle and nuclear DNA (cybrids), whereas this technique also provides a means of introducing genetic information from alien species into tomato. Important developments have come from molecular approaches. Following the construction of an RFLP map, these RFLP markers can be used in tomato to tag quantitative traits bred in from related species. Both RFLP's and transposons are in the process of being used to clone desired genes for which no gene products are known. Cloned genes can be introduced and potentially improve specific properties of tomato especially those controlled by single genes. Recent results suggest that, in principle, phenotypic mutants can be created for cloned and characterized genes and will prove their value in further improving the cultivated tomato.

Speed comparison of digital BiCMOS and CMOS circuits

Today BiCMOS technologies are becoming more and more attractive and offer an interesting alternative to existing technologies. In the paper it will be shown that in digital circuits the bipolar transistor does not necessarily improve BiCMOS speed performance over CMOS in all circumstances. We shall show what conditions are necessary to achieve superior speed and how they can be met. The results depend on channel length and can be easily applied to downscaled BiCMOS technology as well. The estimation is based on theoretical considerations and the results are compared to those achieved on already realised BiCMOS technologies

Silicon microsystems for mechatronic applications

While modern microelectronic fabrication processes allow monolithic integration of millions and millions of electronic devices on tiny silicon chips and thus form a technological base for implementation of high-performance electronic systems, they are also capable of realizing sensing and actuating functions. Although this may require some minor changes in standard processing and thus increase the fabrication costs, the unique combination of sensors, actuators, and electronic circuits can provide implementation of miniature microsystems featuring unprecedented functionality. Their principles, potentials, and applications in mechatronic systems are the central topic of this contribution

A sequential method for noise estimation in switched-capacitor systems using a switching time-frequency domain

The use of continuous-time domain or frequency domain analysis in switched-capacitor systems may often be formally inapplicable due to insufficient mathematical conditions based on the system operating properties itself. This paper introduces a switching time-frequency domain method for the estimation of noise in such systems, while there is no need for periodicity. The switching domain method requires stationarity of the noise process and exploits the system operating conditions. It combines both the time and the frequency domains properly to overcome the difficulties, which exist in nonlinear time-invariant systems. The method is very structured allowing the usage by less experienced professionals and offering a better understanding of the underlying problem to them. The sequential nature of the method makes it predestined to be implemented in existent simulation tools

Double modified internal gate (MIG) pixel for fluorescence imaging applications

In this work we present a double modified internal gate (MIG) pixel structure, fabricated in a slightly modified 0.35µm CMOS process, to be effectively used in, e.g. low-level irradiance fluorescent imaging applications. The pixel structure enables a non-destructive readout, which facilitates a constant monitoring of the molecule fluorescence process. The readout isbased on signal averaging and up-the-ramp sampling current differential readout, which drastically reduces the amount of noise in the pixel output signal. The modified internal gates enable extremely low dark-current and very low-noise operation

Konzept zur optischen Abstandsmessung

US 20110037969 A1 UPAB: 20110302 NOVELTY - The structure (400) has a photoactive region (402) integrated on a substrate for generating charge carriers in responsive to radiation incident on the photoactive region. A reference potential terminal acts as a charge carrier sink. Four transfer gates (404) in the form of metal oxide semiconductor (MOS) capacitors transport the charge carriers generated from the photoactive region. One of the transfer gates connects the photoactive region to the reference potential terminal during a time outside drive intervals, such that the transfer gates are driven at every point in time during a cycle. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for the following: (1) a system for optical distance measurement (2) a method for optical distance measurement by a pixel structure (3) a tangible computer-readable medium storing a set of instructions to perform a method for optical distance measurement by a pixel structure. USE - Time of flight (ToF) pixel structure for measuring optical distance for ToF three-dimensional imaging. ADVANTAGE - The ambient light can be recorded nearly at the same time as the signal and subsequently be subtracted from a useful signal, thus increasing the measuring speed. The reset noise is not dependent on the photoactive region, by separating the detection and read-out nodes, thus reducing small selected floating diffusions when using large-area photoactive regions and read-out nodes of small sizes. The pixel structure offers a way of accumulating charge carriers multiple times within the floating diffusion of the pixel structure, by emitting the radiation pulse multiple times, thus minimizing magnitude of the reset noise and increasing dynamic range and signal-to-noise power ratio

CMOS integrated pixel array for low-level radiation detection using "time compression" parametric amplification

In this work, theoretical modeling and simulations of a 'time compression' parametric amplification pixel array to be used in CMOS imaging for low-level or near IR radiation are presented. The implementation in the higher resistivity substrate process used for smart-power devices, namely the 30 V thin-film 1.0 µm SIMOX-CMOS based on Silicon-on-Insulator technology, enables isolated separation of photoactive and readout circuitry areas when integrated on the same chip. The method presented shows that very high readout current peaks can be generated which are much higher than the mean value of the photocurrent induced. Thus, the parametrically amplified readout signals can be detected by a low-noise peak-detector circuit. The 500x500 µm2 area pixels with internal parametrically controllable amplification and increased pixel fill-in factor (>90%) present higher detection volume due to enlarged deep-depletion region depth caused by a low resistivity substrate. Moreover, the X-Y addressing and the inverse exponential dependence of the parametric amplification on the incoming radiant flux for each pixel provide separately controllable single-pixel internal amplification which improves the intra-scene high dynamic range demands

Modeling and calibration of 3D-Time-of-Flight pulse-modulated image sensors

Scannerless 3D-Time-of-Flight image sensors serve to acquire three-dimensional (3D) information of objects in a scene. This contribution is devoted to modeling and calibration of scannerless 3D-Time-of-Flight image sensors based on pulse modulation. After a short description we introduce a 3D image sensor model that includes system nonlinearities due to nonideal photodetectors and signal processing circuitry. This is followed by the model defined for the nonideal light source waveform. The influence of these nonlinearities on the sensor responsivity and, hence the distance calculation will be shown. Finally, based on our findings we propose an efficient calibration procedure for the proposed distance measurement system