In the framework of Regulation (EC) 1107/2009, concerning the placing of plant protection products (PPP) on the market, FOCUS models are used to predict active substances concentration in groundwater. The predicted environmental concentration in groundwater (PEC) are influenced by active substance specific parameters, namely DT, K and Freundlich coefficient (1/n), whose minimal variation in certain combinations of intervals significantly affects PEC output. Considering that minimal variation are intrinsic in all laboratory studies, this approach may lead to not acceptable variations in the results for regulatory purposes. In the present article, PEC were calculated for all maize crop scenarios, using 808 dummy active substances with different combinations of DT, K and 1/n values, in order to quantify the influence of each single parameter on the final result of PEARL and PELMO models. The results obtained were used to create a classification system for the input parameters K and DT in order to minimise the input uncertainty effects. Even if this approach is scientifically viable yet, due to its conservative nature, it cannot be considered suitable in the regulatory framework, where acceptability of an active substance is strictly related to the limit value of 0.1 μg/L. Nevertheless, this classification system could represent an important screening or preliminary assessment to plan pesticide monitoring programmes. Based on the results of this analysis, it is believed that the assessment of pesticide leaching into groundwater should be revised to take into account this variability. Considering that both PEARL and PELMO FOCUS models deal with interaction between a chemical and a complex system like soil and weather, the selection of input data cannot pretend to rely on single specific number. Considering that intrinsic uncertainty cannot be eliminated from experimental work, a revision of the criteria used to identify the proper input data and a thorough revision of the actual groundwater modelling is recommended.
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http://dx.doi.org/10.1016/j.scitotenv.2022.156314 | DOI Listing |
Med Phys
January 2025
Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Hokkaido, Japan.
Background: The use of iodinated contrast-enhancing agents in computed tomography (CT) improves the visualization of relevant structures for radiotherapy treatment planning (RTP). However, it can lead to dose calculation errors by incorrectly converting a CT number to electron density.
Purpose: This study aimed to propose an algorithm for deriving virtual non-contrast (VNC) electron density from dual-energy CT (DECT) data.
J Comput Chem
January 2025
RIKEN Center for Advanced Intelligence Project, Tokyo, Japan.
QCforever is a wrapper designed to automatically and simultaneously calculate various physical quantities using quantum chemical (QC) calculation software for blackbox optimization in chemical space. We have updated it to QCforever2 to search the conformation and optimize density functional parameters for a more accurate and reliable evaluation of an input molecule. In blackbox optimization, QCforever2 can work as compactly arranged surrogate models for costly chemical experiments.
View Article and Find Full Text PDFHandb Clin Neurol
January 2025
Massachusetts General Hospital, Boston, MA, United States.
Irregular sleep-wake rhythm disorder (ISWRD) is an intrinsic circadian rhythm disorder caused by loss of the brain's circadian regulation, through changes of the input and/or output to the suprachiasmatic nucleus (SCN), or of the SCN itself. Although there are limited prevalence data for this rare disease, ISWRD is associated with neurodegenerative disorders, including the Alzheimer disease (AD) and the Parkinson disease (PD), which will become increasingly prevalent in an aging population. It additionally presents in childhood developmental disorders, psychiatric disorders, and traumatic brain injury (TBI).
View Article and Find Full Text PDFContraception
January 2025
MSI Reproductive Choices, London, England, United Kingdom.
Objective: We sought to develop consensus recommendations for measurement and analysis of data on contraceptive-induced menstrual changes (CIMCs) in contraceptive clinical trials. We built upon previous standardization efforts over the last 50 years and prioritized input from a variety of global experts and current regulatory authority guidance on patient-reported outcomes.
Study Design: We completed a formal consensus-building process with an interdisciplinary group of 57 experts from 30 organizations and 14 countries in five global regions who work across academia, nonprofit research organizations, the pharmaceutical industry, and funding agencies.
Eur J Pharm Sci
January 2025
Sartorius Stedim Biotech GmbH, August-Spindler-Straße 11, 37079 Göttingen ,Germany.
We evaluated algorithms designed to extrapolate extractables data for predicting process equipment-related leachables (PERLs) and assessing PERL exposure in single-use systems (SUSs) and their assemblies. The robustness and sensitivity of these algorithms were tested against variations in input data, including extrapolation algorithms for both short and long contact time extractables data obtained from the standardized extractables protocol provided in USP 〈665〉. Our findings demonstrate that extrapolated data for SUS and assemblies are suitable for safety assessments.
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