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This paper introduces and describes the radio and plasma wave investigation on the STEREO Mission: STEREO/WAVES or S/WAVES. The S/WAVES instrument includes a suite of state-of-the-art experiments that provide comprehensive measurements of the three components of the fluctuating electric field from a fraction of a hertz up to 16 MHz, plus a single frequency channel near 30 MHz. The instrument has a direction finding or goniopolarimetry capability to perform 3D localization and tracking of radio emissions associated with streams of energetic electrons and shock waves associated with Coronal Mass Ejections (CMEs). The scientific objectives include: (i) remote observation and measurement of radio waves excited by energetic particles throughout the 3D heliosphere that are associated with the CMEs and with solar flare phenomena, and (ii) in-situ measurement of the properties of CMEs and interplanetary shocks, such as their electron density and temperature and the associated plasma waves near 1 Astronomical Unit (AU). Two companion papers provide details on specific aspects of the S/WAVES instrument, namely the electric antenna system (Bale et al., Space Sci. Rev., ) and the direction finding technique (Cecconi et al., Space Sci. Rev., ). [ABSTRACT FROM AUTHOR]

The STEREO/WAVES experiment is designed to measure the electric component of radio emission from interplanetary radio bursts and in situ plasma waves and fluctuations in the solar wind. Interplanetary radio bursts are generated from electron beams at interplanetary shocks and solar flares and are observed from near the Sun to 1 AU, corresponding to frequencies of approximately 16 MHz to 10 kHz. In situ plasma waves occur in a range of wavelengths larger than the Debye length in the solar wind plasma λ D ≈10 m and appear Doppler-shifted into the frequency regime down to a fraction of a Hertz. These phenomena are measured by STEREO/WAVES with a set of three orthogonal electric monopole antennas. This paper describes the electrical and mechanical design of the antenna system and discusses efforts to model the antenna pattern and response and methods for in-flight calibration. [ABSTRACT FROM AUTHOR]

Abstract: The methods available for the isolation of Yersinia enterocolitica from foods are generally considered to be less than optimal, and methods for estimation of numbers are lacking. Such methods are needed to understand better the significance of foodborne yersiniosis and to provide data for exposure assessment. We describe a method for the detection and enumeration of Y. enterocolitica containing the pYV virulence plasmid (YeP+) in samples from pork surfaces. The method uses a multiplex PCR targeting the ail and virF genes to detect Y. enterocolitica after incubation of surface swabs in Yersinia enrichment broth according to Ossmer. Enumeration was achieved by adapting the enrichment to a most probable number (MPN) method format. A presumptive result was available within 24 h of sample receipt, and YeP+ isolates were confirmed within four days. The presence/absence and MPN methods were evaluated in a pilot survey of 34 packs of raw pork meat purchased from retail outlets in Christchurch, New Zealand. YeP+ was detected by PCR on meat from 32% of the packs, and YeP+ isolates were obtained from 18% of the samples. YeP+ were present at numbers ranging from 0.30 to 5.42 MPN/cm2. This improved method for the detection and enumeration of YeP+ from meat samples can be used for microbiological surveys to obtain data for assessments of consumer exposure to virulent Y. enterocolitica, and in outbreak investigations. [Copyright &y& Elsevier]

Aims: Little information exists regarding the microbiology of two traditional Maori food preparation processes which may involve fermentations. Preliminary microbiological and chemical analyses were carried out on these two foods in order to identify the fermentations involved (if any). Methods and Results: Testing was carried out on freshly-prepared foods and on those that had been processed and stored. Kina (sea urchins, Evechinus chloroticus) are harvested and then stored either under fresh water or buried underground. The most frequently-occurring process appeared to be an alkaline fermentation. Large numbers of Clostridium perfringens were detected in one set of samples prepared outside of the traditional season, but this was the only pathogen detected. In Kina stored in buried plastic bottles during the traditionally-accepted time of the year, bacterial numbers decreased. Tiroi is prepared from mussels and Puha (sow thistle, Sonchos asper) that have been cooked to some degree, combined and stored. Of three methods used to prepare and store Tiroi, the results for one indicated the possible involvement of a lactic acid fermentation, but the other two methods were effectively only cooking and bottling processes. Conclusions: In the case of Kina, the use of an alkaline fermentation to prepare a seafood for consumption is unusual. One method of Tiroi production is a lactic acid fermentation. Significance and Impact of the Study: If these foods are produced as described and are not either eaten immediately or cooked before consumption, then growth, and intoxication by, Clostridium botulinum might occur. [ABSTRACT FROM AUTHOR]