A week ago I had the opportunity to give a presentation on the application of nonlinear mixed-effects models to degradation kinetics at SETAC Europe in Copenhagen. In case you find yourself wondering what these models are and why we are so enthusiastic about them, this presentation gives a gentle introduction …
more ...Evaluation of degradation study data:
according to FOCUS kinetics and the EFSA guidance on deriving a soil matrix DegT50.
Kinetic method …
more ...I am very happy to be able to announce the publication of the article Taking Kinetic Evaluations of Degradation Data to the Next Level with Nonlinear Mixed-Effects Models. It originated from an investigation of model selection criteria commissioned by the German Federal Environment Agency. During the course of that work …
more ...| 36. | Ranke J, Wöltjen J, Schmidt J, and Comets E (2021) Taking kinetic evaluations of degradation data to the next level with nonlinear mixed-effects models. Environments 8 (8) 71 doi:10.3390/environments8080071 |
| 35. | Ranke J, Meinecke S (2019) Error Models for the Kinetic Evaluation of Chemical Degradation Data Environments … |
More than 10 years after the first code of the 'mkin' package was published, I am happy to announce the release of mkin version 1.0!
With the version number I would like to indicate that the approach taken in the package is mature and battle-proven, and further significant developments …
more ...Working on the application of nonlinear mixed-effects models to chemical degradation data, it became desirable to further speed up the solution of at least the most common degradation models used in the mkin package, simple first-order (SFO) decline of the parent compound coupled to SFO decline of a metabolite, or …
more ...| Ranke J, Wöltjen J (2022) Degradation kinetics on the next level. SETAC Europe 15-19 May 2022, Copenhagen, Denmark slides (pdf) |
| Ranke J (2019) Recent improvements in the definition and identification of error models for chemical degradation data. XVI Symposium on pesticide chemistry 3-5 September, Piacenza, Italy slides (pdf) |
| Ranke J … |
Ever since I have read the refresher of Tjalling Jager on differential equations and likelihood functions, I have been irritated about the common way to express the likelihood of data following a normal distribution using the density function of the normal distribution. The statement that made me wonder was …
more ...| Ranke J, Wöltjen J and Meinecke S (2018) Testdatensätze und Gewichtungsverfahren für die Auswertung von Abbaudaten. Umwelt 2018 mit Beiträgen der Fachgruppe Umweltchemie & Ökotoxikologie der GDCh und Society of Environmental Toxicology and Chemistry - German Language Branch, 9-12 September 2018, Münster, Germany, poster (pdf) |
| Ranke J and Lehmann R (2015) To … |
I am happy to announce that the publication on the software comparison of kinetic evaluation software is now available online! As the supporting information containing the numerical results obtained with the test datasets published on the journal website is marked as "Draft", I have prepared a version for publicaton on …
more ...| Ranke J (2010) Scientific concepts and tools for sustainable chemistry as applied to ionic liquids and antifouling biocides, Habilitation thesis, Universität Bremen, PDF for download |
| Ranke J (2002) Ecotoxicological Risk Profiles of Chemicals - Concept and Application to Antifouling Biocides, PhD thesis, Universität Bremen, PDF for download, printed edition available from … |
| Ranke J, Dinkel H, Pichler K (2010) R - ein neues Element für chemische Analysen. Nachrichten aus der Chemie 58 (April 2010) 453-455 |
| Behrend P, Dünne M, Ranke J* (2006) Determination of Irgarol(R) 1051 from small water samples using Stir-Bar Sorptive Extraction TDS-GC-MS for application in multispecies testing. |
| Ranke J … |
This is a short note about reading tables from common office document formats into R.
After problems with large worksheets I have turned to using the readxl package.
require(readxl)
sheet_names <- excel_sheets("my_file.xls")
d <- read_excel("my_file.xls", sheet = 1, range = "A3:C7", col_names = TRUE)
Recently …
more ...Upon finishing some projects, I found the time to update this web server (from Debian wheezy to Debian jessie) and to give the web site a new design.
And after the start of the new year, the translation of the site to German is completed as well.
more ...With great pleasure I am introducing my new company in this little weblog posting. The company is simply called “Johannes Ranke, wissenschaftlicher Berater”. This means I am running a one-man scientific consulting company. Continuing from my activities at the University of Bremen, at Harlan Laboratories and most recently at Eurofins …
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