Parameter-free aggregation of value functions from multiple experts and uncertainty assessment in multi-criteria evaluation

This paper makes a threefold contribution to spatial multi-criteria evaluation (MCE): firstly by presenting a new method concerning value functions, secondly by comparing different approaches to assess the uncertainty of a MCE outcome, and thirdly by presenting a case-study on land-use change. Even though MCE is a well-known methodology in GIScience, there is a lack of practicable approaches to incorporate the potentially diverse views of multiple experts in defining and standardizing the values used to implement input criteria. We propose a new method that allows generating and aggregating non-monotonic value functions, integrating the views of multiple experts. The new approach only requires the experts to provide up to four values, making it easy to be included in questionnaires. We applied the proposed method in a case study that uses MCE to assess the potential of future loss of vineyards in a wine-growing area in Switzerland, involving 13 experts from research, consultancy, government, and practice. To assess the uncertainty of the outcome three different approaches were used: firstly, a complete Monte Carlo simulation with the bootstrapped inputs, secondly a one-factor-at-a-time variation, and thirdly bootstrapping of the 13 inputs with subsequent analytical error propagation. The complete Monte Carlo simulation has shown the most detailed distribution of the uncertainty. However, all three methods indicate a general trend of areas with lower likelihood of future cultivation to show a higher degree of relative uncertainty

Parameter-free aggregation of value functions from multiple experts and uncertainty assessment in multi-criteria evaluation

This paper makes a threefold contribution to spatial multi-criteria evaluation (MCE): firstly by presenting a new method concerning value functions, secondly by comparing different approaches to assess the uncertainty of a MCE outcome, and thirdly by presenting a case-study on land-use change. Even though MCE is a well-known methodology in GIScience, there is a lack of practicable approaches to incorporate the potentially diverse views of multiple experts in defining and standardizing the values used to implement input criteria. We propose a new method that allows generating and aggregating non-monotonic value functions, integrating the views of multiple experts. The new approach only requires the experts to provide up to four values, making it easy to be included in questionnaires. We applied the proposed method in a case study that uses MCE to assess the potential of future loss of vineyards in a wine-growing area in Switzerland, involving 13 experts from research, consultancy, government, and practice. To assess the uncertainty of the outcome three different approaches were used: firstly, a complete Monte Carlo simulation with the bootstrapped inputs, secondly a one-factor-at-a-time variation, and thirdly bootstrapping of the 13 inputs with subsequent analytical error propagation. The complete Monte Carlo simulation has shown the most detailed distribution of the uncertainty. However, all three methods indicate a general trend of areas with lower likelihood of future cultivation to show a higher degree of relative uncertainty

Parvovirus 4 Infection and Clinical Outcome in High-Risk Populations

Parvovirus 4 (PARV4) is a DNA virus frequently associated with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infections, but its clinical significance is unknown. We studied the prevalence of PARV4 antibodies in 2 cohorts of HIV- and HCV-infected individuals (n = 469) and the correlations with disease status. We found that PARV4 infection frequently occurred in individuals exposed to bloodborne viruses (95% in HCV-HIV coinfected intravenous drug users [IDUs]). There were no correlations between PARV4 serostatus and HCV outcomes. There was, however, a significant association with early HIV-related symptoms, although because this was tightly linked to both HCV status and clinical group (IDU), the specific role of PARV4 is not yet clear

Patient and surgery related factors associated with fatigue type polyethylene wear on 49 PCA and DURACON retrievals at autopsy and revision

<p>Abstract</p> <p>Background</p> <p>Polyethylene wear is an important factor for longevity of total knee arthroplasty. Proven and suspicious factors causing wear can be grouped as material, patient and surgery related. There are more studies correlating design and/or biomaterial factors to in vivo wear than those to patient and surgery related factors. Many retrieval studies just include revision implants and therefore may not be representative. This study is aimed to correlate patient- and surgery- related factors to visual wear score by minimizing design influence and include both autopsy and revision implants. Comparison between the groups was expected to unmask patient and surgery-related factors responsible for wear.</p> <p>Methods</p> <p>The amount of joint side wear on polyethylene retrievals was measured using a modification of an established visual wear score. Fatigue type wear was defined as summation of the most severe wear modes of delamination, pitting and cracks. Analysis of patient and surgery related variables suspicious to cause wear included prospectively sampled patient activity which was measured by self reported walking capacity. Statistical analysis was done by univariate analysis of variance. Activity level and implantation time were merged to an index of use and correlated to the wear score.</p> <p>Results</p> <p>Wear score after comparable implantation time was significantly less in the autopsy group. Even so, fatigue type wear accounted for 84 and 93 % of total wear score on autopsy and revision implants respectively. A highly significant influence on wear score was found in time of implantation (p = 0.002), level of activity (p = 0.025) and inserts belonging to revision group (p = 0.006). No influence was found for the kind of patella replacement (p = 0.483). Body mass index and accuracy of component alignment had no significant influence on visual wear score. Fatigue-type wear in the medial compartment was closely correlated to the index of use in the autopsy (R²= 0.383) and the revision group (R²= 0.813).</p> <p>Conclusion</p> <p>The present study's finding of substantial fatigue type wear in both autopsy and revision retrievals supports the theory that polyethylene fatigue strength is generally exceeded in this type of prosthesis. Furthermore, this study correlated fatigue-type polyethylene wear to an index of use as calculated by activity over time. Future retrieval studies may use activity over time as an important patient related factor correlated to the visual wear score. When evaluating total knee arthroplasty routine follow up, the surgeon must think of substantial wear present even without major clinical signs.</p

Using metallic noncontact atomic force microscope tips for imaging insulators and polar molecules: tip characterization and imaging mechanisms

We demonstrate that using metallic tips for noncontact atomic force microscopy (NC-AFM) imaging at relatively large (>0.5 nm) tip-surface separations provides a reliable method for studying molecules on insulating surfaces with chemical resolution and greatly reduces the complexity of interpreting experimental data. The experimental NC-AFM imaging and theoretical simulations were carried out for the NiO(001) surface as well as adsorbed CO and Co-Salen molecules using Cr-coated Si tips. The experimental results and density functional theory calculations confirm that metallic tips possess a permanent electric dipole moment with its positive end oriented toward the sample. By analyzing the experimental data, we could directly determine the dipole moment of the Cr-coated tip. A model representing the metallic tip as a point dipole is described and shown to produce NC-AFM images of individual CO molecules adsorbed onto NiO(001) in good quantitative agreement with experimental results. Finally, we discuss methods for characterizing the structure of metal-coated tips and the application of these tips to imaging dipoles of large adsorbed molecules. © 2014 American Chemical Society

The Science Performance of JWST as Characterized in Commissioning

This paper characterizes the actual science performance of the James Webb Space Telescope (JWST), as determined from the six month commissioning period. We summarize the performance of the spacecraft, telescope, science instruments, and ground system, with an emphasis on differences from pre-launch expectations. Commissioning has made clear that JWST is fully capable of achieving the discoveries for which it was built. Moreover, almost across the board, the science performance of JWST is better than expected; in most cases, JWST will go deeper faster than expected. The telescope and instrument suite have demonstrated the sensitivity, stability, image quality, and spectral range that are necessary to transform our understanding of the cosmos through observations spanning from near-earth asteroids to the most distant galaxies.Comment: 5th version as accepted to PASP; 31 pages, 18 figures; https://iopscience.iop.org/article/10.1088/1538-3873/acb29

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

Assessing participatory mapping and multi criteria evaluation for land use change analysis

Der massive Landnutzungswandel im Berggebiet beschäftigt Forschung und Praxis: Beispielsweise die Abnahme des Bergackerbaus im Münstertal um 90 % seit 1990 sowie dessen Förderung unter der neuen Schweizer Agrarpolitik seit 2014 oder die prognostizierte Abnahme der Rebflächen im Gebiet des Naturparks Pfyn-Finges um 17-51 % bis 2040. Beide Untersuchungsgebiete in dieser Arbeit liegen innerhalb der Schweizer Alpen. Es stellt sich die Frage, ob diese Entwicklungen im Konflikt mit Anstrengungen zum Erhalt der Biodiversität, der Landschaftsästhetik oder auch des sozialen Gefüges stehen. Um hierzu einen Beitrag zu leisten, erforschten wir Methoden, welche helfen den Landnutzungswandel zu verstehen und zu prognostizieren. Anhand von real existierenden, aktuellen Themen wurde so ein methodischer Beitrag geleistet und gleichzeitig konnten interessante inhaltliche Ergebnisse produziert werden. In dieser Arbeit wurden zwei Methoden erforscht, welche diese Entwicklung räumlich aufzeigen und prognostizieren sollen. Eine untersuchte Methode war, die Bewirtschafter ihre Einschätzung direkt auf Luftbildern einzeichnen zu lassen (partizipatives Kartieren). Eine zweite basierte auf einer multikriteriellen Analyse mit nicht-lokalen Experten. Diese Methoden sind räumlich explizit, zeigen also auf, an welchen Orten sich der Ackerbau, respektive Weinbau verändern wird. Sowohl im Münstertal als auch im Gebiet des Naturparks Pfyn-Finges wurden neben dem partizipativen Kartieren auch Interviews durchgeführt und ein Fragebogen verteilt. Damit konnte aufgezeigt werden wo ein Landnutzungswandel zu erwarten ist und wie dieser von den Bauern und Winzern wahrgenommen wird. Doch können die Bewirtschafter den Landnutzungswandel überhaupt vorhersagen und wenn ja, mit welcher Genauigkeit? Und wie viele Teilnehmer bräuchte es für eine solche Vorhersage? Dieser Frage wurde in einer Fallstudie im Val Müstair nachgegangen. Dabei wurde nicht nur der Zustand unter der neuen Agrarpolitik erfragt, sondern auch wie denn der Zustand 1990 gewesen sei, also zu einer Zeit als es noch deutlich mehr Ackerbau gab. Diese von den Landwirten beigesteuerten Informationen wurden mit einem rekonstruierten Zustand von 1990, sowie Beobachtungen aus den Jahren 2014 und 2015 verglichen. In der Umfrage wurden jeweils drei Massstäbe (1:5 000, 1:12 5000 und 1:25 000) verwendet. Die Auswertung der Studie im Val Müstair zeigte, dass die Bewirtschafter den historischen Zustand genauer und kompletter als die Prognose einzeichnen konnten. Auch zeigte sich, dass dies auf der Skala mit dem grössten Detaillierungsgrad am besten ging. Durch die statistische Methode des Jackknifing konnte herausgefunden werden, mit wie vielen Teilnehmern im Durchschnitt ein ähnliches Resultat wie dasjenige der ganzen Gruppe erreicht worden wäre. Es zeigte sich, dass für die Erfassung des Zustands im Jahr 1990 auf der detailreichsten Skala 5 der 15 Landwirte und für die Prognose 9 der 15 Teilnehmer ausgereicht hätten. Auf der gröbsten Skala hätte man hingegen 7 und 11 Teilnehmer für den historischen, respektive den prognostischen Zustand, gebraucht. Demnach benötigen detailliertere Skalen weniger Teilnehmer für dieselbe Datenqualität und diese fällt grösser aus bei einem vergangenen Zustand als bei einer Prognose. Aber wäre es nicht glaubwürdiger und genauer, man würde die Landschaftsentwicklung mit einem Modell vorhersagen? Die Fallstudie Pfyn-Finges diente der Beanwortung dieser Frage. Es wurden einerseits 33 Winzer mit der Methode der partizipativen Kartierung befragt und andererseits wurde mit 13 nicht lokalen Experten ein multikriterielles Modell erstellt. Für die Befragung wurden den Winzern folgende zwei Fragen gestellt: Erstens, welche Flächen werden in 25 Jahren nicht mehr Weinreben sein und zweitens, welche Flächen werden sicher noch Weinreben sein? Die Differenz dieser Meinungen ergab dann die Prognose. Für das multikriterielle Modell wurden Experten aus Forschung, Verwaltung und Privatwirtschaft gebeten, die wichtigsten Einflussfaktoren für die Umnutzung von Rebparzellen einzuschätzen. Diese Informationen wurden danach in einem Computerprogramm zusammengeführt und es wurde berechnet, mit welcher Wahrscheinlichkeit eine Fläche in 25 Jahren noch weiter bewirtschaftet wird. 25 Jahre entspricht dabei ungefähr der Generation eines Rebstockes: Innerhalb von 25 Jahren wird eine Rebfläche also neu bepflanzt, was meist eine wichtige Entscheidung darstellt, da diese mit hohen Kosten verbunden ist. Es zeigte sich, dass es Regionen gibt, in welchen sowohl das partizipative Kartieren als auch das multikriterielle Modell zu ähnlichen Ergebnissen kommen. Im Bereich des extrapolierten Trends zur Abnahme der Rebfläche (ca. 17-50 % Abnahme), stimmen die beiden Methoden deutlich besser überein, als dies nach Zufall zu erwarten gewesen wäre. In einem Evaluations-Workshop attestierten die Winzer und die nicht-lokalen Experten der multikriteriellen Analyse eine bessere räumliche Auflösung, der kartenbasierten Befragung hingegen eine höhere Plausibilität. Beide Methoden schnitten aber deutlich besser als ein Zufallsmodell ab und sind somit für Prognosen der Landschaftsentwicklung geeignet. Diese Ergebnisse wurden zusätzlich mit Interviewdaten kombiniert und es zeigte sich, dass gewisse Weinberge möglicherweise umgenutzt werden, welche von den Winzern einen grossen kulturellen Wert zugeschrieben bekamen. The considerable change of land use in the mountains is a pressing issue in both research and practice: for instance, the decline of arable farming in the Val Müstair, by approximately 90 % since 1990, and its support under the new Swiss agricultural policy from 2014 or the predicted decline of vineyards in the natural park Pfyn-Finges of about 17–51 % by 2040. Both of the case studies presented within this thesis are located within the Swiss Alps. Does this development conflict with efforts supporting biodiversity, landscape aesthetics or social cohesion? Within this frame, we researched methods that help to develop understanding and accordingly forecast land use changes. Based on real and pressing issues, this thesis delivers methodological contributions, whilst at the same time also delivering interesting content-based insights. This thesis researches two methods in mind of assessing and forecasting the spatial distribution of the named development: one method was asking farmers to deliver their assessment directly on airborne images (participatory mapping); the second method bases on a Multi Criteria Evaluation with non-local experts. Both methods are spatially explicit and therefore show in which locations there are changes expected concerning arable farming or grape-growing, respectively. As well as in the Val Müstair, as in the area of the natural Park of Pfyn-Finges, we not only performed participatory mapping but also interviews and distributed a questionnaire. In so doing, we established where to expect a land use change and how such a change would be perceived by farmers and grape-growers/wine-makers. Are farmers actually able to forecast land use changes and, if so, with what accuracy? And how many participants does one need for such a forecast? These questions were investigated in the case study of the Val Müstair. There, not only a forecast for the arable farmland under the new agricultural policy was sought, but also the situation in the year 1990 when there was much more arable farming. For the participatory mapping, three scales were used (1:5 000, 1:12 500 und 1:25 000). The results then were compared to a reconstructed scenario from the year 1990 and to observations made in the years 2014 and 2015. The results of the study in the Val Müstair showed that the farmers were able to map the historical state more correctly and completely than the prognosis. The best results were yielded on the scale with the highest level of detail. The statistical method of the Jackknifing, allowed inferring the number of participants, which on average would have yielded a result similar to the one of the whole group. On the most detailed scale, 5 of the 15 participants for the historical state, and 9 out of the 15 participants for the prognosis would have been adequate. On the coarsest scale, it would have required 7 and 11 participants for mapping the historic and the prognosis situation, respectively. Hence, more detailed scales require fewer participants for the same data quality, which was bigger for the historic state than for the prognosis. Nonetheless, would it not be more plausible and more accurate to forecast land use change with a model? The case study in Pfyn-Finges served to answer this question. On the one hand, 33 grape-growers/wine-makers were interviewed with the method of participatory mapping, whilst on the other hand, 13 non-local experts were included in building a Multi Criteria Evaluation. For the participatory mapping, grape-growers/wine-makers were asked to two questions: first, in 25 years, which areas are no longer vineyards?; and second, which areas surely will remain as vineyards? The difference between the two opinions yielded the prognosis. For the Multi Criteria Evaluation, experts from research, administration and industry were invited to compare the most important factors for converting a vineyard. From the list of the nine most important factors, the distance to the road and the size of the cultivation unit were considered to have the greatest weight. This information then was combined in a computer program, with the probability of a piece of land remaining a vineyard in 25 years calculated. A period of 25 years corresponds roughly to the generation of a vine: within 25 years, a vineyard will be replanted, thus posing an important question as it is connected to high costs. The results of this study showed the regions in which participatory mapping, as well as the Multi Criteria Evaluation, yields similar results. The methods correspond much more to one another than to a random model within the interval concerning the decrease of vineyards (approximately 17–50 % less). In an evaluation workshop, grape-growers/wine-makers and the non-local experts judged the Multi Criteria Evaluation to have a better resolution and the participatory mapping to have a higher plausibility. Both methods performed much better than a random model, and thus are considered suitable for the prognosis of land use development. These results further were combined with interview data, which showed that some vineyards are possibly converted, to which a high cultural value is ascribed

Super-Resolution Microscopy and Single-Molecule Tracking Reveal Distinct Adaptive Dynamics of MreB and of Cell Wall-Synthesis Enzymes

The movement of filamentous, actin-like MreB and of enzymes synthesizing the bacterial cell wall has been proposed to be highly coordinated. We have investigated the motion of MreB and of RodA and PbpH cell wall synthesis enzymes at 500 ms and at 20 ms time scales, allowing us to compare the motion of entire MreB filaments as well as of single molecules with that of the two synthesis proteins. While all three proteins formed assemblies that move with very similar trajectory orientation and with similar velocities, their trajectory lengths differed considerably, with PbpH showing shortest and MreB longest trajectories. These experiments suggest different on/off rates for RodA and PbpH at the putative peptidoglycan-extending machinery (PGEM), and during interaction with MreB filaments. Single molecule tracking revealed distinct slow-moving and freely diffusing populations of PbpH and RodA, indicating that they change between free diffusion and slow motion, indicating a dynamic interaction with the PGEM complex. Dynamics of MreB molecules and the orientation and speed of filaments changed markedly after induction of salt stress, while there was little change for RodA and PbpH single molecule dynamics. During the stress adaptation phase, cells continued to grow and extended the cell wall, while MreB formed fewer and more static filaments. Our results show that cell wall synthesis during stress adaptation occurs in a mode involving adaptation of MreB dynamics, and indicate that Bacillus subtilis cell wall extension involves an interplay of enzymes with distinct binding kinetics to sites of active synthesis