Set-Theoretic Geology

A ground of the universe V is a transitive proper class W subset V, such that W is a model of ZFC and V is obtained by set forcing over W, so that V = W[G] for some W-generic filter G subset P in W . The model V satisfies the ground axiom GA if there are no such W properly contained in V . The model W is a bedrock of V if W is a ground of V and satisfies the ground axiom. The mantle of V is the intersection of all grounds of V . The generic mantle of V is the intersection of all grounds of all set-forcing extensions of V . The generic HOD, written gHOD, is the intersection of all HODs of all set-forcing extensions. The generic HOD is always a model of ZFC, and the generic mantle is always a model of ZF. Every model of ZFC is the mantle and generic mantle of another model of ZFC. We prove this theorem while also controlling the HOD of the final model, as well as the generic HOD. Iteratively taking the mantle penetrates down through the inner mantles to what we call the outer core, what remains when all outer layers of forcing have been stripped away. Many fundamental questions remain open.Comment: 44 pages; commentary concerning this article can be made at http://jdh.hamkins.org/set-theoreticgeology

Unternehmerische Führung in Sozialen Organisationen

Sozialunternehmen mit einer ausgeprägt unternehmerischen Führung sind erfolgreicher als solche, die weniger stark veränderungs- und marktorientiert ausgerichtet sind, weniger Risiken eingehen, und ihre Mitarbeitenden weniger stark einbeziehen. Das zeigen die Ergebnisse einer Befragung von 257 Sozialen Organisationen aus der ganzen Schweiz, die im Bereich der Integration Wohn-, Arbeits-, Bildungs- oder Beratungsdienstleistungen für Klienten anbie-ten und sich dabei noch überwiegend über Leistungsverträge oder andere öffentliche Gelder (z.B. Kostengutsprachen) finanzieren. Der Organisationserfolg wurde dabei mit Bezug auf die Stakeholderzufriedenheit, die Mitarbeiterfluktuation, das Orga-nisationswachstum und die Veränderung in der Marktfinanzierung gemessen. Das letztgenannte Erfolgsmass spielt angesichts knapper werdender öf-fentlicher Finanzmittel eine zunehmend wichtige Rolle. Die relevanten Erfolgsfaktoren unterscheiden sich dabei je nach Erfolgsmass. Neben einer unter-nehmerischen Führung spielen auch die Wertekongruenz zwischen der haupt- und der ehrenamtlichen Leitung, die Verankerung der Organisationsstrategie, die organisationsinterne Kommunikation und die Organisationsstruktur eine entscheidende Rolle für die Zielerreichung

Landscape of fear or landscape of food? Moose hunting triggers an antipredator response in brown bears

Hunters can affect the behavior of wildlife by inducing a landscape of fear, selecting individuals with specific traits, or altering resource availability across the landscape. Most research investigating the influence of hunting on wildlife resource selection has focused on target species and less attention has been devoted to nontarget species, such as scavengers that can be both attracted or repelled by hunting activities. We used resource selection functions to identify areas where hunters were most likely to kill moose (Alces alces) in southcentral Sweden during the fall. Then, we used step-selection functions to determine whether female brown bears (Ursus arctos) selected or avoided these areas and specific resources during the moose hunting season. We found that, during both day and nighttime, female brown bears avoided areas where hunters were more likely to kill moose. We found evidence that resource selection by brown bears varied substantially during the fall and that some behavioral changes were consistent with disturbance associated with moose hunters. Brown bears were more likely to select concealed locations in young (i.e., regenerating) and coniferous forests and areas further away from roads during the moose hunting season. Our results suggest that brown bears react to both spatial and temporal variations in apparent risk during the fall: moose hunters create a landscape of fear and trigger an antipredator response in a large carnivore even if bears are not specifically targeted during the moose hunting season. Such antipredator responses might lead to indirect habitat loss and lower foraging efficiency and the resulting consequences should be considered when planning hunting seasonsacceptedVersio

Lead exposure in brown bears is linked to environmental levels and the distribution of moose kills

Lead (Pb) is heterogeneously distributed in the environment and multiple sources like Pb ammunition and fossil fuel combustion can increase the risk of exposure in wildlife. Brown bears (Ursus arctos) in Sweden have higher blood Pb levels compared to bears from other populations, but the sources and routes of exposure are unknown. The objective of this study was to quantify the contribution of two potential sources of Pb exposure in female brown bears (n = 34 individuals; n = 61 samples). We used multiple linear regressions to determine the contribution of both environmental Pb levels estimated from plant roots and moose (Alces alces) kills to blood Pb concentrations in female brown bears. We found positive relationships between blood Pb concentrations in bears and both the distribution of moose kills by hunters and environmental Pb levels around capture locations. Our results suggest that the consumption of slaughter remains discarded by moose hunters is a likely significant pathway of Pb exposure and this exposure is additive to environmental Pb exposure in female brown bears in Sweden. We suggest that spatially explicit models, incorporating habitat selection analyses of harvest data, may prove useful in predicting Pb exposure in scavengers. Ursus arctos Pb Scavenger Slaughter remain Resource selection functionacceptedVersio

Fachliches Problemlösen in der Maschinenkonstruktion - Untersuchung von Struktur und Erlernbarkeit mittels multimodaler Technikmodelle

Technische Herausforderungen des Maschinenbauingenieurwesens erfordern umfangreiche Kompetenzen des fachspezifischen, problemlösenden Denkens und Handelns. Im Beitrag wird ein entsprechendes Kompetenzmodell hergeleitet, welches ein strukturiertes Erlernen dieser Kompetenzen ermöglicht und technische Problemlösekompetenz (tPLK) in einem Konstrukt beschreiben, das durch Formulierungshilfen für Aufgabenstellungen einerseits eine Messung ermöglicht und andererseits Lernschritte modularisiert. In einer empirischen Studie wurde die Erlernbarkeit technischer Problemlösekompetenz anhand multimodaler Modelle von typischen Mechanik-Bauteilen ermittelt. In der Auswertung konnte neben einem positiven Effekt bei Motivation, ein mittlerer positiver Effekt bezüglich Systemverständnis festgestellt werden.Schlüsselwörter: Maschinenkonstruktionslehre, Produktentwicklung, technische Problemlöse-kompetenz, multimodale Technikmodell

Fachliches Problemlösen in der Maschinenkonstruktion : Untersuchung von Struktur und Erlernbarkeit mittels multimodaler Technikmodelle

Technische Herausforderungen des Maschinenbauingenieurwesens erfordern umfangreiche Kompetenzen des fachspezifischen, problemlösenden Denkens und Handelns. Im Beitrag wird ein entsprechendes Kompetenzmodell hergeleitet, welches ein strukturiertes Erlernen dieser Kompetenzen ermöglicht und technische Problemlösekompetenz (tPLK) in einem Konstrukt beschreiben, das durch Formulierungshilfen für Aufgabenstellungen einerseits eine Messung ermöglicht und andererseits Lernschritte modularisiert. In einer empirischen Studie wurde die Erlernbarkeit technischer Problemlösekompetenz anhand multimodaler Modelle von typischen Mechanik-Bauteilen ermittelt. In der Auswertung konnte neben einem positiven Effekt bei Motivation, ein mittlerer positiver Effekt bezüglich Systemverständnis festgestellt werden.Schlüsselwörter: Maschinenkonstruktionslehre, Produktentwicklung, technische Problemlöse-kompetenz, multimodale Technikmodell

Spatio-temporal dynamics of aerosol distribution in an urban environment recorded in situ by means of a bike based monitoring system

Aerosol pollution in urban areas is highly variable due to numerous single emission sources such as automobiles, industrial and commercial activities as well as domestic heating, but also due to complex building structures redirecting air mass flows, producing leeward and windward turbulences and resuspension effects. In this publication, it is shown that one or even few aerosol monitoring sites are not able to reflect these complex patterns. In summer 2019, aerosol pollution was recorded in high spatial resolution during six night and daytime tours with a mobile sensor platform on a trailer pulled by a bicycle. Particle mass loadings showed a high variability with PM$_{10}$ values ranging from 1.3 to 221 μg m$^{-3}$ and PM$_{2.5}$ values from 0.7 to 69.0 μg m$^{-3}$. Geostatistics were used to calculate respective models of the spatial distributions of PM$_{2.5}$ and PM10. The resulting maps depict the variability of aerosol concentrations within the urban space. These spatial distribution models delineate the distributions without cutting out the built-up structures. Elsewise, the overall spatial patterns do not become visible because of being sharply interrupted by those cutouts in the resulting maps. Thus, the spatial maps allow to identify most affected urban areas and are not restricted to the street space. Furthermore, this method provides an insight to potentially affected areas, and thus can be used to develop counter measures. It is evident that the spatial aerosol patterns cannot be directly derived from the main wind direction, but result far more from an interplay between main wind direction, built-up patterns and distribution of pollution sources. Not all pollution sources are directly obvious and more research has to be carried out to explain the micro-scale variations of spatial aerosol distribution patterns. In addition, since aerosol load in the atmosphere is a severe issue for health and wellbeing of city residents more attention has to be paid to these local inhomogeneities