Assessing Environmental Risks during the Drug Development Process for Parasitic Vector-Borne Diseases: A Critical Reflection

Parasitic vector-borne diseases (VBDs) represent nearly 20% of the global burden of infectious diseases. Moreover, the spread of VBDs is enhanced by global travel, urbanization, and climate change. Treatment of VBDs faces challenges due to limitations of existing drugs, as the potential for side effects in nontarget species raises significant environmental concerns. Consequently, considering environmental risks early in drug development processes is critically important. Here, we examine the environmental risk assessment process for veterinary medicinal products in the European Union and identify major gaps in the ecotoxicity data of these drugs. By highlighting the scarcity of ecotoxicological data for commonly used antiparasitic drugs, we stress the urgent need for considering the One Health concept. We advocate for employing predictive tools and nonanimal methodologies such as New Approach Methodologies at early stages of antiparasitic drug research and development. Furthermore, adopting progressive approaches to mitigate ecological risks requires the integration of nonstandard tests that account for real-world complexities and use environmentally relevant exposure scenarios. Such a strategy is vital for a sustainable drug development process as it adheres to the principles of One Health, ultimately contributing to a healthier and more sustainable world

Modèle de Gurson à matrice de Coulomb et Drucker-Prager : solutions exactes sous chargement isotrope

Alors que la solution du problème d'analyse limite du modèle sphérique de Gurson - à matrice de von Mises et en symétrie sphérique - est bien connue, elle n'est pas, à notre connaissance, disponible dans les deux cas de chargement isotrope (traction, compression) pour les matrices de Coulomb et Drucker-Prager. Dans la présente note, nous établissons les solutions exactes en traction-compression isotropes pour une sphère creuse soumise à une traction ou compression isotrope externe. On fournit une comparaison avec des approches 3D par éléments finis du problème d'analyse limite. Il convient de mentionner que les solutions analytiques établies sont utiles non seulement en tant que solutions de référence mais qu'elles peuvent aussi servir comme partie de la solution générale en vitesses du modèle de la sphère creuse soumise à des sollicitations arbitraires

Environmental risks of a commonly used pyrethroid: Insights from temporary pond species of the Lake Manyara Basin, Tanzania

This research article was published by Elsevier, 2023Environmental risks posed by widespread pesticide application have attracted global attention. Currently, chemical risk assessments in aquatic environments rely on extrapolation of toxicity data from classic model species. However, similar assessments based on local species could be complementary, particularly for unusual living environments such as temporary ponds. Here, we carried out an environmental risk assessment (ERA) of a pyrethroid model compound, cypermethrin, based on local temporary pond species. First, we measured cypermethrin residue concentrations in rivers, irrigation canals and temporary ponds in the Lake Manyara Basin (LMB). Then, we estimated the environmental risks of cypermethrin by combining these data with acute toxicity data of three resident species across three trophic levels: primary producers (Arthrospira platensis), invertebrate grazers (Streptocephalus lamellifer) and fish (Nothobranchius neumanni). Furthermore, we compared the derived ERA to that obtained using toxicity data from literature of classic model species. Cypermethrin residue concentrations in contaminated systems of the LMB ranged from 0.01 to 57.9 ng/L. For temporary pond species, S. lamellifer was the most sensitive one with a 96 h-LC50 of 0.14 ng/L. Regardless of the assumed exposure concentration (0.01 and 57.9 ng/L), the estimated risks were low for primary producers and high for invertebrate grazers, both for local species as well as for classic model species. The highest detected cypermethrin concentration resulted in a moderate risk estimation for local fish species, while the estimated risk was high when considering classic fish models. Our results confirm that, at least for pyrethroids, ERAs with classic model species are useful to estimate chemical risks in temporary pond ecosystems, and suggest that complementary ERAs based on local species could help to fine-tune environmental regulations to specific local conditions and conservation targets

Pesticide sensitivity of Nothobranchius neumanni, a temporary pond predator with a non-generic life-history

This research article was published by Elsevier in Volume 291, Part 1, March 2022Pesticides are crucial to improve agricultural productivity, but often adversely affect surrounding aquatic systems and their fauna. To determine the environmental risk of pesticides, routine ecotoxicological tests are performed on several organisms, including standard fish models. However, these typically do not include fish species from variable habitats and with non-generic life-histories. In particular, inhabitants from temporary ponds such as annual killifish are conventionally understood to be resilient to natural stressors which could translate to higher pesticide resistance or, alternatively, trade-off with their resistance to pesticides and render them more sensitive than classic fish models. Using standard exposure tests, we assessed short-term toxicity effects of two commonly used pesticides, Roundup and cypermethrin, on the annual killifish Nothobranchius neumanni, and compared its sensitivity with that of classic fish models. For Roundup, we found a 72 h-LC50 of 1.79 ± 0.11 mg/L, which is lower than the values reported for zebrafish, medaka, fathead minnow and rainbow trout, suggesting that N. neumanni is more sensitive to the compound. The opposite was true for cypermethrin, with a 72 h-LC50 of 0.27 ± 0.03 mg/L. However, these LC50-values do not deviate strongly from those reported for other fish species, supporting earlier findings in the congeneric N. furzeri that the sensitivity of annual killifish to pollutants is similar to that of classic fish models despite their assumed robustness to environmental stress

Mariage et divorce dans la banlieue de Dakar

Thoré Luc. Mariage et divorce dans la banlieue de Dakar. In: Cahiers d'études africaines, vol. 4, n°16, 1964. pp. 479-551

"Tar man bort konst försvinner folks tankar" : En studie om estetiska lärprocesser och ämnesintegration i gymnasieskolan

Utifrån intresset för estetiska lärprocesser och hur det påverkar elevers lärande i ämnesintegration har jag gjort en undersökning i årskurs ett på gymnasiets estetiska program om elevers lärande genom estetiska lärprocesser i ämnesintegration. Syftet är att tydliggöra vad den estetiska lärprocessens bidrar med vid ämnesintegrering. De frågeställningar jag utgått ifrån är ”På vilket sätt kan estetiska lärprocesser bidra till lärandet i ämnesintegration i projektform? Hur ser estetiska lärprocesser ut vid ämnesintegration med engelska och svenska? Hur kan man genom ämnesintegration med Estetisk kommunikation 1 bredda förståelsen för innehållet i både den kursen och andra kurser?”. Ramen för undersökningen är ett projekt som löper under sju veckor där kurserna Estetisk kommunikation, Engelska 5 och Svenska 1 integreras. Det är en kvalitativ studie där jag använder mig av metodtriangulering för att söka svar på frågorna. Genom etnografisk metod med deltagande observation, intervju med fokusgrupp, insamlade artefakter och enkät tar jag fram empirin. Den teoretiska ramen är strukturalistiskt teori och diskursanalys. I bearbetning och analys av materialet framkommer en kunskapsprocess där eleverna går från faktakunskaper till förståelse för att slutligen nå färdighet och förtrogenhet. Den pedagogiska strukturen skapar förutsättningar för den estetiska lärprocessen genom den ram som projektet utgör. I djupintervju med en fokusgrupp framträder en diskurs där eleverna poängterar vikten av delaktighet i lärprocessen för sitt engagemang och sin entusiasm till skolarbetet. Enkätmaterialet visar att redovisningar i grupp är en källa till kunskap genom att eleverna interagerar med varandra. Detta visar på hur strukturen för undervisningen påverkar lärandet genom det pedagogiska upplägget. Några slutsatser jag kan dra är att estetiska lärprocesser bidrar positivt till lärandet eftersom det praktiska arbetet kräver kunskaper på en färdighets- och förtrogenhetsnivå för att genomföras. Jag kan även se att kunskap är en process som börjar i fakta, vilket eleverna ger uttryck för. Genom ämnesintegration får eleverna en sammanhållen process i sitt lärande