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.

Modular low-power, high-speed CMOS analog-to-digital converter of embedded systems

One of the main trends of microelectronics is toward design for integrated systems, i.e., system-on-a-chip (SoC) or system-on-silicon (SoS). Due to this development, design techniques for mixed-signal circuits become more important than before. Among other devices, analog-to-digital and digital-to-analog converters are the two bridges between the analog and the digital worlds. Besides, low-power design technique is one of the main issues for embedded systems, especially for hand-held applications. Modular Low-Power, High-Speed CMOS Analog-to-Digital Converter for Embedded Systems aims at design techniques for low-power, high-speed analog-to-digital converter processed by the standard CMOS technology. Additionally this book covers physical integration issues of A/D converter integrated in SoC, i.e., substrate crosstalk and reference voltage network design

High-speed analog CMOS pipeline system

We present a switched-capacitor readout system for high speed analog signals. It consists of a 10 MHz four-channel delay-line chip with 58 samples per channel and a 12 channel buffer chip with a sampling rate of 1 MHz and a depth of nine samples. In addition the buffer chip includes an analog multiplexer with 25 inputs for the buffer channels and for 13 additional unbuffered signals. Both chips have been fabricated in CMOS-technology and will be used for the readout of the ZEUS high resolution calorimeter. The circuit and chip concept will be presented and some design optimizations will be discussed. Measurements from integrated prototypes will be given including some experimental data from irradiated chips

Rule-based analog circuit design

A prototype of rule-based environment for analog integrated circuit design is presented. It features a hierarchical design style, multifunctionality, and adaption capability for its knowledge bases. The prototype called AC/DC has been realized as a set of cooperating tools for design and verification. The overall system can act like an automatic tool as well as a design assistant. In its current version it can design CMOS operational amplifiers and switched-capacitor (SC)-filters

Flexible silicon structures for a retina implant

Worldwide there are some different approaches toward the development of a retina implant as a visual prosthesis for people suffering from retinitis pigmentosa (RP). In this work we present an epiretinal implant system with the emphasis on the retina stimulator which differs significantly from other approaches by using flexible single-crystal silicon. This substrate provides on the one hand the flexibility required by the implant to adapt the retina shape. On the other hand it enables us to integrate complex circuitry monolithically on the stimulator chip. Especially circuitry for a bus system can be placed in the immediate vicinity of the stimulating microelectrode array ensuring the possibility of increasing the number of microelectrodes. The CMOS-compatible fabrication process consists of a combination of wet chemical anisotropic etching producing an silicon mesa array and plasma etching forcoming the flexible crosspieces between those 'silicon islands'

Development of the front end electronics for the ZEUS high resolution calorimeter

The design of the pipelined data acquisition system for the high resolution ZEUS calorimeter is described. Results of measurements with prototype electronics are given. The development and design of the pipeline data aquisition system for the high resolution ZEUS calorimeter is described. Details of the front and analog card and the performance are given. A description of the custom pipeline and buffer multiplexer chips is given, analog with test results for the pipeline chip. In addition, some results are presented for a CCD test system built to evaluate the pipeline principles using the ZEUS calorimeter prototype at the CERN PS

Pleomorphic Adenoma of the Salivary Glands With Intravascular Tumor Deposits A Diagnostic Pitfall

The diagnosis of pleomorphic adenoma (PA) of salivary glands is usually straightforward posing few diagnostic problems for the general surgical histopathologist. The purpose of our investigation was to present a series of 22 cases of PA of major salivary glands, each of which contained small foci of tumor within vascular spaces. This feature has previously been described very rarely in PA and may represent a significant diagnostic pitfall. The patients included 12 women and 10 men, ranging in age at diagnosis from 17 to 82 years. Histopathologically, all 22 tumors displayed the features of PA with mixed epithelial and myoepithelial growth patterns and chondromyxoid areas. None of these neoplasms showed any cytologic evidence of malignancy. In all cases, there were multiple dilated thin-walled and/or muscular thick-walled blood vessels containing small intraluminal collections of neoplastic cells with or without myxoid stromal components. The intravascular tumor cells expressed cytokeratins, and in some cases they were also immunoreactive for S-100 protein, GFAP, D2-40, and p63 protein. The intravascular location of the neoplastic cells was confirmed by CD31, CD34, and factor VIII-related antigen immunostains. Reaction for D2-40 was negative in the endothelium of the involved vessel in all cases, confirming that they were vascular rather than lymphatic channels. Seven patients (36%) underwent fine-needle aspiration biopsy 25 days to several years before excision of the tumor. Follow-up of the patients in our series revealed no cases of recurrence or metastasis (range, 6mo to 9.5 y; mean 3.8 y; median 3.5 y). The biological significance of intravascular tumor in PA is not clear, but there is growing evidence that it is an innocuous phenomenon that might be related to artifactual spillage caused by tumor injury presumably by either fine-needle aspiration or intraoperative trauma.361116741682IGAMH CR (Internal Grant Agency of Health Ministry, Czech Republic) [NT13701-4/2012]IGAMH CR (Internal Grant Agency of Health Ministry, Czech Republic) [NT13701-4/2012