Measuring preferences on environmental damages in LCIA. Part 2: choice and allocation questions in panel methods

Background, aim, and scope: Within life cycle impact assessment (LCIA), ‘panel methods' has become a common term to denominate methods that elicit and measure stakeholders' stated preferences on environmental impact categories. Such panel procedures use different question formats to elicit information on weighting across impact categories from the stakeholders. The two most frequently used question formats are score allocation and choice between alternatives. The differences between these two question formats were analyzed in order to give advice on how to frame future panel procedures. Materials and methods: A choice-based weighting procedure (choice experiment) for the three damage categories of human health, ecosystems quality, and resources was developed and executed. A logistic regression model was applied in order to estimate the weighting factors for the polled sample. Results from this choice-based procedure were compared to the results from an allocation-based procedure described in part 1 of this paper. Results: When weighting factors are elicited by score allocation questions, panelists tend to distribute the scores more equally. A factor of 1.5 between the least and the most weighted damage category was found. Weighting factors from a choice experiment were more spread, i.e., the most important category was weighted considerably higher, whereas the other two categories were weighted less. Thus, for the choice experiment, the range between the most and the least weighted categories was considerably bigger—by about a factor of 4. Discussion: A comparison of the two procedures revealed that the weighting of environmental damage categories is considerably influenced by the question of format. The reason for these variations may be different cognitive routines that are applied. In addition, several advantages and shortcomings of choice experiments are discussed. Conclusions: The developed, choice-based procedure provided meaningful results. Thus, choice experiments, often used for the monetary valuation of environmental goods, can also be applied in LCIA to elicit nonmonetary weighting factors. Recommendations and perspectives: Choice experiments form a new interesting approach for weighting procedures in the future as they have some advantages over the often used score allocation methods. They are simple and more realistic than other procedures, as panelists have practiced in choice tasks from everyday life. We, therefore, recommend such choice-based procedures for future panel studie

Measuring Preferences on Environmental Damages in LCIA. Part 1: Cognitive Limits in Panel Surveys (9 pp)

-: Part 1: Cognitive Limits in Panel Surveys · Part 2: The Question Format in Panel Surveys This series of two papers discusses the elicitation of weights for damage categories in LCIA with the aid of panel surveys. The papers focus especially on methodological aspects in panel surveys. Part 1 discusses potential cognitive limits of the panel members to understand the reference that is weighted. Part 2 focuses on the influence of the question format and compares results from two different weighting tasks: discrete choice (between alternatives) and score allocation. Goal, Scope and Background: The weighting of environmental impacts and damages on the safeguard subjects Human Health, Ecosystems, and Resources is a significant step of full aggregated LCIA. Panel surveys have become a common approach in LCIA research to investigate the preferences of stakeholders on environmental impacts and damages. Despite the numerous studies, the knowledge on how to elicit reliable weights is still poor and inconsistent. We present a questionnaire study with 58 environmental science students to investigate so-called framing effects in panel surveys. Main Features: The study investigates the significance of different framings, which were provided by three references. In addition, the significance of quantitative information provided in the questionnaire is tested. The references are (a1) safeguard subjects without specified additional information, (a2) damages in Europe as they are perceived by the panelist, and (a3) quantified scenarios derived from Eco-indicator99. All participants ranked and rated the importance of the safeguard subjects three times, once within each reference system. According to a test-of-scope study, quantitative information given to the panelist was varied. One level (b1) included data from the Ecoindicator99 methodology, whereas the other group (b2) received data with significantly higher Human Health damages and lower Ecosystem damages, ceteris paribus. This design allows testing the influence of quantitative data on the rating. Results: The weighting of the safeguard subjects (a1) reveals that Human Health is considered a slightly more important safeguard subject than Ecosystems. However, both are judged to be significantly more important than Resources. This picture changes for the references (a2) and (a3) where damages were weighted. For both references, the respondents rated damages to Ecosystems as most important followed by Resources and Human Health, showing by far the lowest weights. Therefore, the framing of the reference that was weighted played a significant role. The ratings of the subgroups (b1) and (b2) did not differ with respect to the importance of damages, though substantially different quantitative information was given. Conclusion and Outlook: The participants of the study were obviously insensitive with respect to quantitative information provided. This raises three questions, which are discussed. What is the mental model upon which respondents base their beliefs and values? Can we expect that 'more sophisticated' subjects would respond differently? Which prerequisites should an empirical weighting procedure fulfill in order to incorporate numerical data? We propose different approaches for future procedures in order to accurately analyze these question

Relationships between landscape morphology, climate and surface erosion in northern Peru at 5°S latitude

The northern segment of the Peruvian Andes is affected by a twofold climate with measurable implications on landscapes and landscape dynamics. During ‘normal' or ‘neutral' years easterly winds bring rain from the Atlantic and the Amazon Basin to the Sierras, which results in a seasonal climate with rather low-intensity precipitations. In contrast, during the large-scale warm phase of the ENSO cycle, El Niños transfer moisture from the Pacific to the Peruvian coast by westerly winds and result in high-intensity precipitation. We investigate the effects of this twofold climate for the case of the Piura drainage basin at ca. 5°S latitude (northern Peru). In the headwaters that have been under the influence of the easterlies, the landscape is mantled by a thick regolith cover and dissected by a network of debris flow channels that are mostly covered by a thick layer of unconsolidated sediment. This implies that in the headwaters of the Piura River sediment discharge has been limited by the transport capacity of the sediment transfer system. In the lower segment that has been affected by high-intensity rainfall in relation to the westerlies (El Niños), the hillslopes are dissected by debris flow channels that expose the bedrock on the channel floor, implying a supply-limited sediment discharge. Interestingly, measurements at the Piura gauging station near the coast reveal that, during the last decades, sediment was transferred to the lower reaches only in response to the 1982-1983 and 1997-1998 El Niño periods. For the latter period, synthetic aperture radar (SAR) intensity images show that the locations of substantial erosion are mainly located in areas that were affected by higher-than-average precipitation rates. Most important, these locations are coupled with the network of debris flow channels. This implies that the seasonal easterlies are responsible for the production of sediment through weathering in the headwaters, and the highly episodic El Niños result in export of sediment through channelized sediment transport down to the coastal segment. Both systems overlap showing a partially coupled sediment production-delivery syste

Contribution de la protéine PB1-F2 des virus influenza A dans l’adaptation d’une souche virale à son hôte

Influenza A viruses (IAV) cause flu in birds and some mammals, including humans. They are an important issue for both veterinary and human health. The PB1-F2 protein is an IAV virulence factor whose functions depends on the host as well as the viral strain. The molecular mechanisms associated with PB1-F2 are still enigmatic, but its ability to modulate the host immune response suggests that PB1-F2 contributes to viral fitness. Our work aimed to compare the properties of PB1-F2 in avian and mammalian hosts. In cellular models, an avian H7N1 PB1-F2 had no effect on the host response whereas a human H3N2 PB1-F2 was pro-inflammatory. Conversely, PB1-F2 H7N1 exacerbated the virulence in mice and promoted a strong inflammatory response. Surprisingly, a chimeric H3N2 virus expressing the avian PB1-F2 induced a reduced inflammation in mice compared to H3N2 wild type virus. Thus, the functions of PB1-F2 are not strictly transposable and strongly depend on the viral context in which it is expressed. Finally, we have mapped the interactions between PB1-F2 and host proteins in avian and human cells using the biotin ligase BioID2. We have identified both specific and common PB1-F2 regulated biological pathways. Our work provides elements characterizing the functions of PB1-F2 in avian and mammalian hosts but also in crossing host species barrier or with a reassortant virus expressing an avian PB1-F2Les virus influenza A (IAV) sont les agents étiologiques de la peste aviaire et de la grippe chez certains mammifères, dont l’Homme. Ils constituent une importante problématique de santé vétérinaire et humaine. La protéine PB1-F2 est un facteur de virulence des IAV dont les fonctions varient selon l’hôte ainsi que la souche virale considérés. La compréhension des mécanismes d’action de cette protéine est incomplète mais son aptitude à moduler la réponse immunitaire de l’hôte suggère une contribution de PB1-F2 dans l’adaptation d’une souche virale à son hôte. L’objectif de ce travail de thèse a été de caractériser les propriétés de PB1-F2 chez l’hôte aviaire et mammifère. En modèles cellulaires, nous n’avons pas observé de modulation de la réponse de l’hôte par la protéine PB1-F2 d’un virus aviaire H7N1 tandis que la protéine PB1-F2 d’un virus H3N2 humain présente une action pro inflammatoire. A l’inverse, en modèle murin, la PB1- F2 du virus H7N1 contribue de façon majeure à la pathogénicité en exacerbant la réponse inflammatoire. De façon surprenante, un virus chimérique de fond génétique H3N2 exprimant la protéine PB1-F2 aviaire H7N1 induit une inflammation réduite chez la souris par rapport au virus H3N2 sauvage. Ainsi, les fonctions de PB1-F2 ne sont pas strictement transposables et dépendent fortement du contexte viral dans lequel elle est exprimée. Enfin, les interactomes différentiels des protéines PB1-F2 ont été définis en cellules aviaires et humaines par biotinylation de proximité (BioID2). Nous avons identifié des voies biologiques régulées par les protéines PB1-F2 étudiées et différencié les voies spécifiques des voies communes. Nos travaux apportent des éléments de caractérisation des fonctions de PB1-F2 chez l’hôte aviaire et mammifère mais également dans un contexte de franchissement de la barrière d’espèce ou de virus réassortant exprimant une PB1-F2 d’origine aviair

Massentransport in Geklüfteten Medien - Der Übergang zum Anormalen Transport

Substantial understanding of the processes involved in fluid flow and tracer transport in geological systems can be gained from the use of numerical simulations. Regardless of the nature or scale of a geological system, the probability of encountering fractures in hard rock units is high. Therefore, modelling flow and transport in fractures and fracture networks is a key component of almost any complex hydrogeological simulation. Over the last few decades, with the increase in computational power and the availability of increasingly sophisticated and powerful specialized modelling software, numerical models have become increasingly commonplace, and are meanwhile regarded as vital tools in the wide field of geoscience. This work portrays the development of a series of numerical models, with discrete fracture network geometry, based on the knowledge of an actual fracture network gained through prior experiments performed at the Grimsel Test Site (GTS) in the Swiss Alps. A three dimensional reconstruction of the actual fracture network geometry is developed from the extensive photographic data set provided by the Excavation Project (EP) and used as the basis for purely advective particle tracking models, as well as for fully advective-dispersive transport models. Realistic fracture apertures based on actual fracture measurements are generated through a geostatistical method and their influence upon flow and transport is studied. Various degrees of heterogeneity with regard to aperture distributions are generated and used in a Monte Carlo approach to examine their influence. Further, the retardation effects of matrix diffusion are also considered and incorporated into the models by means of a new semi-analytical method included in the FEM code Rockflow/Geosys V4. The resulting breakthrough curves are analysed and fitted with several analytical solutions, including advective dispersive transport with matrix diffusion and continuous time random walks (CTRW). It is shown that the standard advection dispersion equation (ADE) is not suitable for approximating or predicting breakthrough curves from heterogeneous models. The development of the various models portrayed herein depended strongly on the ongoing advances made in the available modelling codes and in new and dedicated preprocessing tools. Several newly developed methods and tools were tested and applied during the project. For the first time, a group of numerical simulations is presented, that incorporates complex fracture network geometry based on actual field data, geostatistically generated realistic apertures and the effect of matrix diffusion. This new level of realism provides the basis for new insights into the role of heterogeneity, matrix diffusion and the combination of both in the transition toward anomalous transport.Das Wissen über die an Fluss- und Transportprozessen beteiligten Mechanismen kann durch die Verwendung von numerischen Simulationen deutlich erweitert werden. Unabhängig der Natur oder der Grössenordnung des untersuchten Systems ist das Auftreten von Klüften und Spalten in Felsstrukturen sehr wahrscheinlich. Daher stellt das Modellieren von Fluss- und Transport in geklüfteten Medien eine wesentliche Komponente der meisten komplexen hydrogeologischen Simulationen dar. Mit der andauernden Entwicklung von immer Leistungsfähigeren Computern und dem Aufkommen von spezialisierter und leistungsfähiger Software zur numerischen Modellierung haben sich numerische Simulationen in den letzten Jahren und Jahrzehnten etabliert, und sind nun als wichtiges Werkzeug im weiten Feld der Geowissenschaften anerkannt. Diese Arbeit stellt die Entwicklung und Anwendung einer Reihe solcher numerischer Modelle dar. Die Modelle basieren auf dem bestehenden Wissen über ein natürliches Kluftsystem in den Schweizer Alpen, welches durch frühere Experimente am Felslabor Grimsel untersucht wurde. Eine dreidimensionale Rekonstruktion der Kluftgeometrie wird entwickelt und als Basis für sowohl rein advective "Particle Tracking" Modelle, als auch für advektiv-dispersive Transportmodelle verwendet. Realistische Kluftöffnungsweiten, basierend auf gemessenen Weiten von untersuchten Klüften, werden mittels einer Geostatistischen Methode für die Modelle generiert. Der Einfluss dieser Heterogenität auf Fluss und Transport wird untersucht. Vergleichbare Öffnungsweitenverteilungen mit unterschiedlich starker Heterogenität werden generiert und deren Einfluss im Rahmen eines Monte Carlo Ansatzes Untersucht. Ebenso wird der retardierende Einfluss von Matrix Diffusion in den Modellen berücksichtigt und untersucht. Die resultierenden Durchbruchskurven werden mittels einer Auswahl an analytischen Methoden, unter anderem mit Matrix Diffusion und "Continuous Time Random Walks" (CTRW), angepasst und interpretiert. Es wird dabei gezeigt, dass die herkömliche Advektions-Dispersions Gleichung (ADE) nicht geeignet ist um Durchbrüche von heterogenen Modellen anzunähern oder vorauszusagen. Die Entwicklung der vorgestellten Modelle wird ermöglicht durch die fortwährende Entwicklung im Bereich von numerischen Modellierungscodes, sowie durch neue und verbesserte Werkzeugen zur Erstellung und Verwaltung der Modellgeometrie. Etliche neue Methoden und Werkzeuge wurden im Rahmen der Arbeit getestet und verwendet. Erstmals wird eine Gruppe von numerischen Simulationen vorgestellt, welche complexe, auf Felddaten beruhende Kluftnetzwerkgeometrien beinhalten, sowie geostatistisch generierte Öffnungsweiten und Matrix Diffusion. Dieser neue Grad an Realitätsnähe bildet die Basis für neue Erkenntnisse bezüglich der Rolle von Heterogenitäten, Matrix Diffusion und deren Kombination im Übergangsbereich zum anormalen Transport

Contribution of viral protein PB1-F2 in the adaptation of influenza A viruses to their host

Les virus influenza A (IAV) sont les agents étiologiques de la peste aviaire et de la grippe chez certains mammifères, dont l’Homme. Ils constituent une importante problématique de santé vétérinaire et humaine. La protéine PB1-F2 est un facteur de virulence des IAV dont les fonctions varient selon l’hôte ainsi que la souche virale considérés. La compréhension des mécanismes d’action de cette protéine est incomplète mais son aptitude à moduler la réponse immunitaire de l’hôte suggère une contribution de PB1-F2 dans l’adaptation d’une souche virale à son hôte. L’objectif de ce travail de thèse a été de caractériser les propriétés de PB1-F2 chez l’hôte aviaire et mammifère. En modèles cellulaires, nous n’avons pas observé de modulation de la réponse de l’hôte par la protéine PB1-F2 d’un virus aviaire H7N1 tandis que la protéine PB1-F2 d’un virus H3N2 humain présente une action pro inflammatoire. A l’inverse, en modèle murin, la PB1- F2 du virus H7N1 contribue de façon majeure à la pathogénicité en exacerbant la réponse inflammatoire. De façon surprenante, un virus chimérique de fond génétique H3N2 exprimant la protéine PB1-F2 aviaire H7N1 induit une inflammation réduite chez la souris par rapport au virus H3N2 sauvage. Ainsi, les fonctions de PB1-F2 ne sont pas strictement transposables et dépendent fortement du contexte viral dans lequel elle est exprimée. Enfin, les interactomes différentiels des protéines PB1-F2 ont été définis en cellules aviaires et humaines par biotinylation de proximité (BioID2). Nous avons identifié des voies biologiques régulées par les protéines PB1-F2 étudiées et différencié les voies spécifiques des voies communes. Nos travaux apportent des éléments de caractérisation des fonctions de PB1-F2 chez l’hôte aviaire et mammifère mais également dans un contexte de franchissement de la barrière d’espèce ou de virus réassortant exprimant une PB1-F2 d’origine aviaireInfluenza A viruses (IAV) cause flu in birds and some mammals, including humans. They are an important issue for both veterinary and human health. The PB1-F2 protein is an IAV virulence factor whose functions depends on the host as well as the viral strain. The molecular mechanisms associated with PB1-F2 are still enigmatic, but its ability to modulate the host immune response suggests that PB1-F2 contributes to viral fitness. Our work aimed to compare the properties of PB1-F2 in avian and mammalian hosts. In cellular models, an avian H7N1 PB1-F2 had no effect on the host response whereas a human H3N2 PB1-F2 was pro-inflammatory. Conversely, PB1-F2 H7N1 exacerbated the virulence in mice and promoted a strong inflammatory response. Surprisingly, a chimeric H3N2 virus expressing the avian PB1-F2 induced a reduced inflammation in mice compared to H3N2 wild type virus. Thus, the functions of PB1-F2 are not strictly transposable and strongly depend on the viral context in which it is expressed. Finally, we have mapped the interactions between PB1-F2 and host proteins in avian and human cells using the biotin ligase BioID2. We have identified both specific and common PB1-F2 regulated biological pathways. Our work provides elements characterizing the functions of PB1-F2 in avian and mammalian hosts but also in crossing host species barrier or with a reassortant virus expressing an avian PB1-F