Temperature and food quantity effects on the harpacticoid copepod Nitocra spinipes : combining in vivo bioassays with population modeling

The harpacticoid copepod Nitocra spinipes has become a popular model species for toxicity testing over the past few decades. However, the combined influence of temperature and food shortage, two climate change-related stressors, has never been assessed in this species. Consequently, effects of three temperatures (15, 20 and 25˚C) and six food regimes (between 0 and 5 × 10^5 algal cells/mL) on the life cycle of N. spinipes were examined in this study. Similarly to other copepod species, development times and brood sizes decreased with rising temperatures. Mortality was lowest in the 20˚C temperature setup, indicating a close-by temperature optimum for this species. Decreasing food concentrations led to increased development times, higher mortality and a reduction in brood size. A sex ratio shift toward more females per male was observed for increasing temperatures, while no significant relationship with food concentration was found. Temperature and food functions for each endpoint were integrated into an existing individual-based population model for N. spinipes which in the future may serve as an extrapolation tool in environmental risk assessment. The model was able to accurately reproduce the experimental data in subsequent verification simulations. We suggest that temperature, food shortage, and potentially other climate change-related stressors should be considered in environmental risk assessment of chemicals to account for non-optimal exposure conditions that may occur in the field. Furthermore, we advocate combining in vivo bioassays with population modeling as a cost effective higher tier approach to assess such considerations

Tag der Artenvielfalt in Heidelberg : am 3. Juni 2000

Tagungsband zum Heidelberger Tag der Artenvielfalt am 3.Juni 2000, der im Rahmen des 2.Geo-Tages der Artenvielfalt durchgeführt wurde. In diesem Buch werden der Ablauf der Veranstaltung, die Befunde einer Artenerhebung und allgemeine Beiträge zu folgenden Bereichen dargestellt: Kulturlandschaft und Lebensräume im Untersuchungsgebiet Heidelberg (2 Beiträge), Zoologie (21 Beiträge), Botanik (9 Beiträge) und verschiedene andere Themen (z. B. Naturschutz, Landespflege und Vorschläge für Exkursionen; 10 Beiträge) Die komplette Liste einer Arterhebung auf Heidelberger Gemarkung (3. Juni und zeitliches Umfeld), die von mehr als 100 Experten erarbeitet wurde, ist im Anhang dargestellt. Der Tag der Artenvielfalt wurde vom Zoologischen Institut initiiert und von der Stadt Heidelberg unter der Schirmherrschaft der Oberbürgermeisterin Beate Weber sowie der Vhs unterstützt. Beteiligt waren: Messschiff Max Honsell der LfU, Ökomobil der BNL, Geologisches-Paläontologisches Museum, Botanischer Garten, Pädagogische Hochschule, Tiergarten Heidelberg und Biologische Bundesanstalt

Актуализация баз данных геоинформационных атласов в автоматизированном режиме

This study represents a first attempt at applying a fuzzy inference system (FIS) and an adaptive neuro-fuzzy inference system (ANFIS) to the field of aquatic biomonitoring for classification of the dosage and time of benzo[a]pyrene (BaP) injection through selected biomarkers in African catfish (Clarias gariepinus). Fish were injected either intramuscularly (i.m.) or intraperitoneally (i.p.) with BaP. Hepatic glutathione S-transferase (GST) activities, relative visceral fat weights (LSI), and four biliary fluorescent aromatic compounds (FACs) concentrations were used as the inputs in the modeling study. Contradictory rules in FIS and ANFIS models appeared after conversion of bioassay results into human language (rule-based system). A "data trimming" approach was proposed to eliminate the conflicts prior to fuzzification. However, the model produced was relevant only to relatively low exposures to BaP, especially through the i.m. route of exposure. Furthermore, sensitivity analysis was unable to raise the classification rate to an acceptable level. In conclusion, FIS and ANFIS models have limited applications in the field of fish biomarker studies

Impact of Chemical Pollution on Threatened Marine Mammals: A Systematic Review

[Abstract] Marine mammals, due to their long life span, key position in the food web, and large lipid deposits, often face significant health risks from accumulating contaminants. This systematic review examines published literature on pollutant-induced adverse health effects in the International Union for Conservation of Nature (IUCN) red-listed marine mammal species. Thereby, identifying gaps in literature across different extinction risk categories, spatial distribution and climatic zones of studied habitats, commonly used methodologies, researched pollutants, and mechanisms from cellular to population levels. Our findings reveal a lower availability of exposure-effect data for higher extinction risk species (critically endangered 16%, endangered 15%, vulnerable 66%), highlighting the need for more research. For many threatened species in the Southern Hemisphere pollutant-effect relationships are not established. Non-destructively sampled tissues, like blood or skin, are commonly measured for exposure assessment. The most studied pollutants are POPs (31%), metals (30%), and pesticides (17%). Research on mixture toxicity is scarce while pollution-effect studies primarily focus on molecular and cellular levels. Bridging the gap between molecular data and higher-level effects is crucial, with computational approaches offering a high potential through in vitro to in vivo extrapolation using (toxico-)kinetic modelling. This could aid in population-level risk assessment for threatened marine mammals.This research received no specific grant from funding agencies in the public, commercial, or not-for-profit sectors. L.B. acknowledges support from a Horizon Europe Marie Skłodowska-Curie Actions Postdoctoral Fellowship funded by the European Union (ID: 101066127

On the Design of Peer Punishment Experiments

We discuss how technologies of peer punishment might bias the results that are observed in experiments. A crucial parameter is the “fine-to-fee” ratio, which describes by how much the punished subjects income is reduced relatively to the fee the punishing subject has to pay to inflict punishment. We show that a punishment technology commonly used in experiments embeds a variable fine-to-fee ratio and show that it confounds the empirical findings about why, whom, and how much subjects punish

Quantification of nitroaromatic explosives in contaminated soil using MALDI-TOF mass spectrometry

Contamination from various sources is a global environmental and health threat, with mining and military activities in particular having spread nitroaromatic compounds, such as 2,4,6-trinitrotoluene and its degradation products and by-products, to the soil. The investigation and monitoring of large contaminated areas requires new detection methods since the established ones are expensive and time-consuming. Hence, we established a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI--TOF MS) method using 1,5-diaminonaphthalene as the matrix substance and an internal standard for quantification. Analyzing standard substances, we found specific signals for radical and fragment ions of different nitrotoluenes and nitrobenzenes with good reproducibility and detection limits down to 0.25 ng/μL. The analysis of soil sample extracts from a former production site showed clear signals for 2,4,6-trinitrotoluene and the primary degradation products aminodinitrotoluenes. Furthermore, quantification gave results comparable to those obtained by conventional liquid chromatography--tandem mass spectrometry analysis. The MALDI-TOF MS method has a comparatively lower reproducibility, with relative standard deviations of 6% to 20% for multiple measurements of standard solutions and soil sample extracts. Nevertheless, a comparison of both methods revealed the advantages of MALDI-TOF MS analysis of explosive-contaminated areas with regard to costs, time, and handling. Finally, our MALDI-TOF MS method fulfills all the needs for high sample throughput and can therefore be a valuable screening tool for explosive-contaminated areas

Разработка и исследование химических реагентов с повышенной эффективностью растворения в технологических жидкостях для строительства скважин

Объектами исследования являются системы промывочных жидкостей на водной основе. Цель работы – разработать методы модифицирования полимерных реагентов и исследовать эффективность их применения в промывочных жидкостях для строительства скважин. В результате исследования предложены три способа модифицирования полимерных реагентов (суспендирование, создание покрытий, частичное сшивание) для повышения их эффективности растворения в промывочных жидкостях для строительства скважин; выявлены ограничения предложенных способов повышения эффективности растворения полимерных реагентов; сформулированы рекомендации по целесообразности применения каждого из предложенных способов модифицирования. Область применения: промывочные жидкости для строительства скважин.Objects of study: water-based drilling fluids. The purpose of the work is to develop methods for modification of polymer reagents and to investigate an effectiveness of their use in drilling fluids for drilling wells. As a result of the study, three methods were proposed for modifying polymer reagents (suspension, coating, partial crosslinking) to increase their dissolution efficiency in drilling fluids; limitations of the proposed methods for increasing the dissolution efficiency of polymer reagents were identified; recommendations were made on the appropriateness of each of the proposed methods of modification. Scope: drilling fluids