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Sina Leipold Anna Petit-Boix Anran Luo Hanna Helander Machteld Simoens Weslynne S. Ashton Callie W. Babbitt Alba Bala Catharina R. Bening Morten Birkved Fenna Blomsma Casper Boks Alessio Boldrin Pauline Deutz Teresa Domenech Navarro Ferronato Alejandro Gallego-Schmid Damien Giurco Kersty Hobson Roope Husgafvel Cynthia Isenhour Mait Kriipsalu Donato Masi Joan Manuel F. Mendoza Leonidas Milios Monia Niero Deepak Pant Keshav Parajuly Stefan Pauliuk Marina P. P. Pieroni Jessika Luth Richter Michael Saidani Marzena Smol Laura Talens Peiró Stijn van Ewijk Walter J. V. Vermeulen Dominik Wiedenhofer Bing Xue 《Journal of Industrial Ecology》2023,27(1):6-18
The current enthusiasm for the circular economy (CE) offers a unique opportunity to advance the impact of research on sustainability transitions. Diverse interpretations of CE by scholars, however, produce partly opposing assessments of its potential benefits, which can hinder progress. Here, we synthesize policy-relevant lessons and research directions for a sustainable CE and identify three narratives—optimist, reformist, and skeptical—that underpin the ambiguity in CE assessments. Based on 54 key CE scholars’ insights, we identify three research needs: the articulation and discussion of ontologically distinct CE narratives; bridging of technical, managerial, socio-economic, environmental, and political CE perspectives; and critical assessment of opportunities and limits of CE science–policy interactions. Our findings offer practical guidance for scholars to engage reflexively with the rapid expansion of CE knowledge, identify and pursue high-impact research directions, and communicate more effectively with practitioners and policymakers. 相似文献
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Although extensive studies provided molecular and pharmacological characterization of metabotropic P2Y receptors for extracellular nucleotides, little is still known about their quaternary structure. By the use of transfected cellular systems and SDS-PAGE, in our previous work we established the propensity of P2Y4 receptor to form dimeric interactions. Here we focused on endogenously expressed P2Y4 and P2Y6 subtypes, comparing their oligomeric complexes under Blue Native (BN) gel electrophoresis. We provided evidence that P2Y4 and P2Y6 receptors form high order complexes in native neuronal phenotypes and that the oligomers can be disaggregated down to the dimeric P2Y4 or to the dimeric and monomeric P2Y6 receptor. Moreover, dimeric P2Y4 and monomeric P2Y6 proteins display selective microdomain partitioning in lipid rafts from specialized subcellular compartments such as synaptosomes. Ligand activation by UTP shifted the oligomerization of P2Y6 but not of P2Y4 receptor, as analysed by BN electrophoresis. Finally, whereas transfected P2Y4 and P2Y6 proteins homo-interact and posses the appropriate domains to associate with all P2Y1,2,4,6,11 subtypes, in naive PC12 cells the endogenous P2Y4 forms hetero-oligomers only with the P2Y6 subunit. In conclusion, our results indicate that quaternary structure distinguishing P2Y4 from P2Y6 receptors might be crucial for specific ligand activation, membrane partitioning and consequent functional regulation. 相似文献
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Francesco Lagona Monia Ranalli Elisabetta Barbi 《Biometrical journal. Biometrische Zeitschrift》2020,62(6):1508-1524
Multivariate spatial count data are often segmented by unobserved space-varying factors that vary across space. In this setting, regression models that assume space-constant covariate effects could be too restrictive. Motivated by the analysis of cause-specific mortality data, we propose to estimate space-varying effects by exploiting a multivariate hidden Markov field. It models the data by a battery of Poisson regressions with spatially correlated regression coefficients, which are driven by an unobserved spatial multinomial process. It parsimoniously describes multivariate count data by means of a finite number of latent classes. Parameter estimation is carried out by composite likelihood methods, that we specifically develop for the proposed model. In a case study of cause-specific mortality data in Italy, the model was capable to capture the spatial variation of gender differences and age effects. 相似文献
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Physiological and biochemical effects of Olea europaea leaf extracts from four phenological growth stages on the oogenesis of female locust Locusta migratoria
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Khemais Abdellaoui Meriem Hazzoug Olfa Boussadia Meriam Miladi Ghofrane Omri Fatma Acheuk Monia Ben Halima‐Kamel Mohamed Brahem 《Physiological Entomology》2018,43(2):129-139
The effects of olive leaf extract (OLE) are studied on several reproductive variables and the ovarian biochemical composition of Locusta migratoria (Orthoptera: Acrididae) adult females. The methanolic extracts are prepared from the leaves sampled during four phenological growth stages of olive tree: cluster formation (Cf), swelling inflorescence buds (Sib), full flowering (Ff) and endocarp hardening (Eh). When applied to adult females during the pre‐ovipositional phase, the treatment elicites a significant adverse effect on their reproductive potential. Indeed, OLE significantly reduces both fecundity and fertility and affects oocyte growth during the first gonadotrophic cycle, as indicated by measurements of ovarian weight, length of terminal oocytes and ovarian index. Furthermore, OLE is examined with respect to ovarian biochemical components. Biochemical analyses reveal a significant reduction of ovarian contents of proteins, lipids and carbohydrates, suggesting a disruption in the incorporation of the haemolymph metabolites in the oocytes and an interference of OLE with the vitellogenesis process. The antigonadotrophic effect is confirmed by a histological study of the ovaries, which clearly shows a delay in ovarian development and in yolk accumulation in the basal oocytes of treated females. The most effect is noted with the extract prepared from the leaves collected at the swelling inflorescence buds for all measured parameters, which appears to be related to its high content of polyphenols. 相似文献