Morphogenesis: Pharyngeal Arch Development in Ambystoma tigrinum

This study examines pharyngeal arch (PA) development in the eastern tiger salamander (Ambystoma tigrinum) during transformation. The PA is a series of six arches that give structure to the gills and is involved in feeding and moving water across the pharyngeal and branchial chambers. Proper remodeling of the PA during transformation is essential to ensure proper respiratory functioning and feeding in terrestrial salamanders. Salamander carcasses were obtained from salamanders that died before, during, or after transformation to a terrestrial state. The carcasses were cleared and stained with alcian blue (cartilage identification) and alizarin red (bone identification) to evaluate PA remodeling during transformation. The majority of salamanders exhibited abnormal PA remodeling. Based on current findings, we hypothesize that the abnormal ossification may be in part due to a changed morphogenesis process.https://openriver.winona.edu/urc2019/1115/thumbnail.jp

Guidance Document on Measurement Uncertainty for GMO Testing Laboratories

The report outlines the technical issues related to the estimation of measurement uncertainty (MU) involved in the GMO sector. In particular it gives guidance to GMO testing laboratories how to estimate the analytical variability of quantitative analytical results obtained by real-time PCR. Two selected approaches for the estimation of MU are presented in detail; references to alternative approaches are given. The first approach are given. The first approach presented in detail is using data from collaborative trial in combination with in-house quality control data for the estimation of MU. An alternative approach using data from within-laboratory samples for the estimation of MU is presented.JRC.D.2-Reference material

Validation of the performance of a GMO multiplex screening assay based on microarray detection

A new screening method for the detection and identification of GMO, based on the use of multiplex PCR followed by microarray, has been developed and is presented. The technology is based on the identification of quite ubiquitous GMO genetic target elements first amplified by PCR, followed by direct hybridisation of the amplicons on a predefined microarray (DualChip® GMO, Eppendorf, Germany). The validation was performed within the framework of a European project (Co-Extra, contract no 007158) and in collaboration with 12 laboratories specialised in GMO detection. The present study reports the strategy and the results of an ISO complying validation of the method carried out through an inter-laboratory study. Sets of blind samples were provided consisting of DNA reference materials covering all the elements detectable by specific probes present on the array. The GMO concentrations varied from 1% down to 0.045%. In addition, a mixture of two GMO events (0.1% RRS diluted in 100% TOPAS19/2) was incorporated in the study to test the robustness of the assay in extreme conditions. Data were processed according to ISO 5725 standard. The method was evaluated with predefined performance criteria with respect to the EC CRL method acceptance criteria. The overall method performance met the acceptance criteria; in particular, the results showed that the method is suitable for the detection of the different target elements at 0.1% concentration of GMO with a 95% accuracy rate. This collaborative trial showed that the method can be considered as fit for the purpose of screening with respect to its intra- and inter-laboratory accuracy. The results demonstrated the validity of combining multiplex PCR with array detection as provided by the DualChip® GMO (Eppendorf, Germany) for the screening of GMO. The results showed that the technology is robust, practical and suitable as a screening too

Wirtschaftsdüngermanagement – ein Beitrag zum klimafreundlichen Boden-management in Westsibirien

Die Landwirtschaft in der westsibirischen Oblast Tjumen zeichnet sich durch kontrastreiche Produktionsformen aus. Großbetriebe und Kleinsterzeuger produzieren ca. zu gleichen Teilen tierische und pflanzliche Erzeugnisse für den Absatzmarkt. Hinsichtlich der Umwelt- und Klimaverträglichkeit tragen die Großbetriebe zu größerer Umweltbelastung und mehr Treibhausgasemissionen aus dem Wirtschaftsdünger-Handling bei als die Kleinsterzeuger