This unit describes two methods for preparing genomic DNA from plant tissue. In the first method, plant cells are lysed with ionic detergent, treated with protease, and subsequently purified by cesium chloride (CsCl) density gradient centrifugation. The second method is based upon a series of treatments with the nonionic detergent cetyltrimethylammonium bromide (CTAB) to lyse cells and purify nucleic acid. Nucleic acid is recovered from the final CTAB solution by isopropanol or ethanol precipitation. The first method, although somewhat more lengthy, results in highly purified nucleic acid. The second method requires fewer manipulations, results in very high yields (approximately 10-fold higher per gram fresh tissue depending on species and condition of starting material), and produces DNA that is less pure but nonetheless suitable in quality for use in many molecular biology manipulations.
Over the last 15 years, and particularly in the last 5 years, a robust framework of open geoprocessing standards and sensor web enablement standards has been developed by the OGC, an open, consensus-based standards development organization, in close cooperation with other standards development organizations. These standards have been implemented by developers in a wide variety of commercially successful geoprocessing software products and Web services. The standards are coming into wide use in domains of activity such as ocean observation, defence and intelligence, and civil protection, and they are beginning to be used in many other domains, including the domain of natural hazards and risks. A description of the standards is provided, along with a discussion of their benefits and the changes they tend to encourage in business and institutional arrangements. It is expected that use of these standards will become ubiquitous as new computing models ('cloud computing', notably) replace old computing models. It is also expected that this progress will have significant consequences for environmental risk and hazard assessment and management as well as the institutions, practices and methods of sciences that produce and use geospatial information.
UAVs are a disruptive technology bringing new geographic data and information to many application domains. UASs are similar to other geographic imagery systems so existing frameworks are applicable. But the diversity of UAVs as platforms along with the diversity of available sensors are presenting challenges in the processing and creation of geospatial products. Efficient processing and dissemination of the data is achieved using software and systems that implement open standards. The challenges identified point to the need for use of existing standards and extending standards. Results from the use of the OGC Sensor Web Enablement set of standards are presented. Next steps in the progress of UAVs and UASs may follow the path of open data, open source and open standards.
The Open Geospatial Consortium (OGC) is an international voluntary consensus standards organization founded in 1994. In the OGC, hundreds of commercial, governmental, nonprofit, and research organizations worldwide collaborate in an open consensus process to develop and promote the implementation of open standards for geospatial content and services, geographic information system (GIS) data processing, and GIS data sharing. OGC standards support interoperable solutions that “geo‐enable” apps on mobile devices, location‐based services, the Internet of Things, and mainstream web applications. OGC standards empower technology developers to make geospatial information and services accessible and useful with any application that needs to be geospatially enabled.
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