Validierung: Charakterisierte Methoden für klare Fragen

Validation means to proof if a laboratory method is able to answer a question from the customer or not. For validation procedures the question has to be specific to be answered and the method has to be characterised. The growing organic market needs methods which allow the characterisation of the food. Therefore methods have to be developed which reflect the systemic approach in organic agriculture. First of all these methods shall differentiate food products grown and processed organically from those derived from other production processes. Moreover for product oriented quality control the quality criteria and their limits have to be defined within the organic market

Entwicklung der Biokristallisation für die Unterscheidung von Proben mittels computerunterstützter Texturanalyse und visueller Bildauswertung

Because of the growing market in organic produce screening methods are needed which allow the characterization of the food. Since many years the so called biocrystallization technique has been used to characterize products derived from different farming systems yet the method was not validated. The results of our investigations in the last three years show that the method can fulfill the requirements for the validation process due to international standards. The sample preparation and the crystallization procedures could be standardised and documented. For the crystallization factors of influence were described and controlled. In addition to the traditionally used visual evaluation a new computerized image texture analysis program was succesfully applied. Furthermore visual evaluation was standardized due to international norms used in sensory analysis. With a panel of trained people, crystal patterns from fresh and freeze dried carrot samples can be differentiated as statistically significant. This is a siginificant step forward because this allows the development of a structure analysis programme and will contribute to connect the different approaches within the researches in this field

Estimating Ixodes ricinus densities on the landscape scale

Background: The study describes the estimation of the spatial distribution of questing nymphal tick densities by investigating Ixodes ricinus in Southwest Germany as an example. The production of high-resolution maps of quest-ing tick densities is an important key to quantify the risk of tick-borne diseases. Previous I. ricinus maps were based on quantitative as well as semi-quantitative categorisations of the tick density observed at study sites with differ-ent vegetation types or indices, all compiled on local scales. Here, a quantitative approach on the landscape scale is introduced. Methods: During 2 years, 2013 and 2014, host-seeking ticks were collected each month at 25 sampling sites by flag-ging an area of 100 square meters. All tick stages were identified to species level to select nymphal ticks of I. ricinus, which were used to develop and calibrate Poisson regression models. The environmental variables height above sea level, temperature, relative humidity, saturation deficit and land cover classification were used as explanatory variables. Results: The number of flagged nymphal tick densities range from zero (mountain site) to more than 1,000 nymphs/100 m2. Calibrating the Poisson regression models with these nymphal densities results in an explained variance of 72 % and a prediction error of 110 nymphs/100 m2 in 2013. Generally, nymphal densities (maximum 37

Organic wheat quality from a defined Italian field-trial

Organic and conventional wheat grain (Triticum aestivum and Triticum durum) samples coming from a defined field trial in Italy were measured in 2005 and 2006 for their total protein content and the contents of lutein and zeaxanthin. Additionally the samples were analyzed by means of the biocrystallization method. The grain samples could be differentiated by the total protein content, which was higher in the conventional samples. The organic samples contained a higher lutein content in Triticum aestivum but lower in Triticum durum. Biocrystallization differentiated Triticum durum from Triticum aestivum and organic from conventional grown samples when visual evaluation was applied. Differentiation of farming systems was possible for biocrystallization evaluated with computerized texture analysis but not significant for all samples and years

Authentication of organic wheat samples from a long-term trial using biocrystallization

Organic and conventional wheat grain samples from a long-term field trial were tested with standardised biocrystallization method. In 1999-2006 the organic samples can be separated from the conventional samples using computerized texture analysis and standardised visual evaluation of the crystallization patterns. Moreover the organic samples can be classified in 2005-2006 after training in 2003

The capillary dynamolysis method as a char-acterized tool for crop quality determination

The growing organic market demands for methods which can describe food quality within the organic system. With the capillary dynamolysis technique patterns are produced on thin-layer chromatographic paper and evaluated as a fingerprint of the sample as a whole. To be applied in routine analysis the method has to be standardised according to international standard norms. After the laboratory process had been documented and a visual pattern evaluation method had been developed and applied for the evaluation of the patterns, the method was standard-ized for selected carrot and wheat samples, which is described here. For standardization several factors of influence were tested and the reproducibility between 3 different laboratories in the EU was investigated. Wheat and carrot samples from different varieties as well as different nitrogen fertilization could be differ-entiated as statistical significant

Validation of HPLC-methods for measurements of secondary plant compounds in carrots followed by multivariate statistical analysis

Polyphenolic compounds are measured in carrots. Beside measurements of total phenolic contents (TPC) as a sum parameter, HPLC methods are developed and validated to detect the single constituents. The methods are applied for carrot samples from different field experiments as well as farming systems. The aim of the experiments is to test if: 1. carrot samples from different treatments can be differentiated 2. the sum parameters are correlated with the HPLC data (single constituents) 3. the application of multivariate statistics can help to classify the samples according to their treatmen

Analysis of Outcomes in Ischemic vs Nonischemic Cardiomyopathy in Patients With Atrial Fibrillation A Report From the GARFIELD-AF Registry

IMPORTANCE Congestive heart failure (CHF) is commonly associated with nonvalvular atrial fibrillation (AF), and their combination may affect treatment strategies and outcomes