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Dimitra Ioannidou Niko Heeren Guido Sonnemann Guillaume Habert 《Journal of Industrial Ecology》2019,23(4):751-766
In recent literature, the concept of criticality aspires to provide a multifaceted risk assessment of resource supply shortage. However, most existing methodologies for the criticality assessment of raw materials are restricted to a fixed temporal and spatial reference system. They provide a snapshot in time of the equilibrium between supply and demand/economic importance and do not account for temporal changes of their indicators. The static character of criticality assessments limits the use of criticality methodologies to short‐term policy making of raw materials. In the current paper, we argue for an enhancement of the criticality framework to account for three key dynamic characteristics, namely changes of social, technical, and economic features; consideration of the spatial dimension in site‐specific assessments; and impact of changing governance frameworks. We illustrate how these issues were addressed in studies outside of the field of criticality and identify the dynamic parameters that influence resource supply and demand based on a review of studies that belong to the general field of resource supply and demand. The parameters are grouped in seven categories: extraction, social, economic, technical, policy, market dynamics, and environmental. We explore how these parameters were considered in the reviewed studies and propose ways and specific examples of addressing the dynamic effects in the criticality indicators. Furthermore, we discuss the current work on future scenarios to provide reference points for indicator benchmarks. The insights and guidelines derived from the review and our recommendations for future research set the foundations for an enhanced dynamic and site‐specific criticality assessment framework. 相似文献
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Ammar Bader Lirio Panizzi Pier Luigi Cioni Guido Flamini 《Central European Journal of Biology》2007,2(2):206-212
The composition of the essential oils obtained from the leaves and the flowers of Achillea ligustica (Asteraceae) growing in Sicily has been studied. The main constituents of the leaves were 4-terpineol (19.3%), carvone (8.9%),
γ-terpinene (7.2%) and β-phellandrene (6.8%). 4-terpineol (12.0%), carvone (10.0%), and β-phellandrene (5.4%), along with linalool (20.4%) and cedrol (4.3%) were detected in the flower’s oil. Furthermore, the antimicrobial
activity of the essential oils and of some of the main constituents were assayed on bacteria and fungi.
In memory of Prof. Ivano Morelli (1940–2005) 相似文献
126.
The guanine nucleotide-binding protein Ras occurs in solution in two different conformational states, state 1 and state 2 with an equilibrium constant K(12) of 2.0, when the GTP analogue guanosine-5'-(beta,gamma-imido)triphosphate or guanosine-5'-(beta,gamma-methyleno)triphosphate is bound to the active centre. State 2 is assumed to represent a strong binding state for effectors with a conformation similar to that found for Ras complexed to effectors. In the other state (state 1), the switch regions of Ras are most probably dynamically disordered. Ras variants that exist predominantly in state 1 show a drastically reduced affinity to effectors. In contrast, Ras(wt) bound to the GTP analogue guanosine-5'-O-(3-thiotriphosphate) (GTPgammaS) leads to (31)P NMR spectra that indicate the prevalence of only one conformational state with K(12) > 10. Titration with the Ras-binding domain of Raf-kinase (Raf-RBD) shows that this state corresponds to effector binding state 2. In the GTPgammaS complex of the effector loop mutants Ras(T35S) and Ras(T35A) two conformational states different to state 2 are detected, which interconvert over a millisecond time scale. Binding studies with Raf-RBD suggest that both mutants exist mainly in low-affinity states 1a and 1b. From line-shape analysis of the spectra measured at various temperatures an activation energy DeltaH(|) (1a1b) of 61 kJ.mol(-1) and an activation entropy DeltaS(|) (1a1b) of 65 J.K(-1).mol(-1) are derived. Isothermal titration calorimetry on Ras bound to the different GTP-analogues shows that the effective affinity K(A) for the Raf-RBD to Ras(T35S) is reduced by a factor of about 20 compared to the wild-type with the strongest reduction observed for the GTPgammaS complex. 相似文献
127.
Cheng H Liu Z Blum W Byrd JC Klisovic R Grever MR Marcucci G Chan KK 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,850(1-2):206-212
A specific and sensitive HPLC-MS/MS method for the quantitative determination of valproic acid (VPA) and its metabolite, 2-propyl-4-pentenoic acid in human plasma has been developed, using VPA-d15 as the internal standard. The method was based on pre-column derivatization using 4-dimethylaminobenzylamine dihydrochloride. The derivatives were separated with a gradient elution and quantified by positive electrospray ionization with multiple reaction monitoring. The assay provides routine quantification limits of 200 ng/mL for VPA and 20 ng/mL for 4-ene VPA with within- and between-day coefficients of variation of <10%. This method has been applied to the analysis of plasma samples obtained from patients treated with this drug. 相似文献
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Mammalian heparanase: what is the message? 总被引:3,自引:0,他引:3
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MegaPlex PCR: a strategy for multiplex amplification 总被引:1,自引:0,他引:1
'MegaPlex PCR' is a robust technology for highly multiplexed amplification of specific DNA sequences. It uses target-specific pairs of PCR primers that are physically separated by surface immobilization. Initial surface-based amplification cycles are then coupled to efficient solution-phase PCR using one common primer pair. We demonstrate this method by co-amplifying and genotyping 75 unselected human single-nucleotide polymorphism (SNP) loci. 相似文献
130.
Seasonal variation of the chemical constituents of the essential oil of Santolina etrusca from Italy
The seasonal variation of the essential oil, in terms of both yield and composition, of a population of Santolina etrusca (Asteraceae) is reported in detail for different aerial parts, including sterile branches, fertile branches, and capitula. The yields generally increased from November to June, and then decreased in August and September. The main constituents of the sterile branches were 1,8-cineole and viridiflorol. The oil from fertile branches was characterized by myrcene as principal compound, whereas the essential oil obtained from the capitula contained germacrene D as the main constituent. Several compounds, as identified by GC and GC/MS, were found to prevail during the cold season. 相似文献