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Entry points for assessing 'fair shares' in national mitigation contributions
No full textFairness considerations have long been central to the international climate change mitigation discourse, generating numerous scientific and philosophical debates. Yet, there remains a pressing need for practical guidance on developing assertions of fairness in national mitigation contributions. The Paris Agreement mandates that subsequent nationally determined contributions (NDCs) submitted under Article 4 represent a progression compared to previous NDCs. Further decisions under the Paris Agreement mandate that NDCs include clear and transparent considerations of fairness, as recalled in the first Global Stocktake. We propose a practical approach to this, comprising a set of 'entry points' that represent key stages where decisions are taken in 'fair share' quantifications, from interpreting foundational principles to selecting indicators and presenting results. By bridging the gap between scholarly debates and practical application, this work supports the integration of clear and transparent fairness considerations into climate policy commitments. We demonstrate the use of our approach through a case study
Deep and fast volumetric imaging of neuronal activity
No full textOptische Methoden wie die Multiphotonenmikroskopie, kombiniert mit fluoreszenzbasierten Sensoren, ermöglichen es, Hunderte oder sogar Tausende von Neuronen parallel zu untersuchen. Dennoch gibt es bei der in vivo Bildgebung des gesamten Gehirns mit räumlicher Auflösung unter einem Millimeter und zeitlicher Auflösung im Millisekundenbereich weiterhin erhebliche Herausforderungen. Diese Arbeit befasst sich mit zwei wesentlichen Hindernissen der optischen Bildgebung in der neurobiologischen Forschung: der begrenzten Bildgebungstiefe und den langsamen volumetrischen Bildraten. Erstens wird die optische Mikroskopie durch Gewebestreuung grundlegend eingeschränkt. In der ersten Studie dieser Arbeit habe ich eine Methode zur Messung und Korrektur gestreuter Wellenfronten mittels Drei-Photonen-Anregung entwickelt. 3-Photonen F-SHARP profitiert von verbesserter Bildgebungstiefe aufgrund der höhergradigen nichtlinearen Anregung und längeren Anregungswellenlänge. Darüber hinaus habe ich gezeigt, dass die Konvergenzgeschwindigkeit und Robustheit des Algorithmus zur Wellenfrontmessung im Vergleich zur Zwei-Photonen-Variante verbessert wird. Zweitens ist die volumetrische funktionelle Bildgebung tiefer Gehirnbereiche häufig durch den langsamen Prozess des sequentiellen Abrasterns begrenzt. Die Abtastrate kann durch das Durchlaufen vorselektierter Ziele (sogenanntes Random Access Scanning) erhöht werden. In der zweiten Studie habe ich einen neuartigen Random-Access-Scanning-Ansatz entwickelt, beruhend auf einem schnellen, MEMS-basierten Spatial Light Modulator (SLM) mit Pixeln in einer eindimensionalen Linienkonfiguration. Diese Methode, genannt SPARCLS, erreicht eine dreidimensionale Abtastrate von 340 kHz. Zusammenfassend erleichtern die in dieser Arbeit entwickelten Methoden sowohl die Gewebepenetration als auch die volumetrische Bildgebung mit höherer Abtastrate und ermöglichen so eine tiefere und schnellere Untersuchung neuronaler Aktivität mittels optischer Methoden.Optical methods, such as multiphoton microscopy combined with fluorescence-based sensors, make it possible to study hundreds or even thousands of neurons in parallel. Nevertheless, in vivo whole-brain imaging at sub-micrometer spatial and millisecond temporal resolution still faces significant challenges. This thesis addresses two major obstacles for in vivo imaging in neurobiological research: limited imaging depth and slow volumetric imaging rates.
First, optical microscopy is fundamentally limited by tissue scattering. In the first study presented in this thesis, I developed a method for the measurement and correction of scattered wavefronts using three-photon excitation. Three-photon F-SHARP profits from the improved penetration depth due to the longer wavelength light and higher-order nonlinear excitation. Furthermore, I demonstrated that the convergence speed and robustness of the wavefront sensing algorithm are improved compared to its two-photon counterpart. Second, volumetric functional imaging of deep brain areas is often constrained by the slow process of raster scanning. Random access scanning iterates through preselected targets and can significantly speed up the sampling rate. In the second study, I developed a novel random access scanning approach making use of a fast MEMS-based spatial light modulator (SLM). This method, termed SPARCLS, achieves three-dimensional scanning at 340 kHz update rate using SLM pixels arranged in a one-dimensional line configuration. SPARCLS scanning was validated by visualizing glutamate dynamics in mouse organotypic slices as well as zebrafish larvae using the genetically encoded glutamate indicator iGluSnFR3. Together, the methods developed in this thesis facilitate both tissue penetration and rapid volumetric scanning for deeper and faster imaging of neuronal activity
Mapping subsea permafrost around Tuktoyaktuk Island (Northwest Territories, Canada) using electrical resistivity tomography
No full textAlong much of the Arctic coast, shoreline retreat and sea level rise combine to inundate permafrost. Once inundated by seawater, permafrost usually begins to degrade. Tuktoyaktuk Island (Beaufort Sea, Northwest Territories, Canada) is an important natural barrier protecting the harbor of Tuktoyaktuk but will likely be breached within the next 2 decades. The state of subsea permafrost and its depth distribution around the island are, however, still largely unknown. We collected marine electrical resistivity tomography (ERT) surveys (vertical electrical soundings) north and south of Tuktoyaktuk Island using a floating cable with 13 electrodes in a quasi-symmetric Wenner–Schlumberger array configuration. We filtered the data with a new approach to eliminate potentially incorrect measurements due to a curved cable and inverted the profiles with a variety of parameterizations to estimate the position of the ice-bearing permafrost table (IBPT) below the seafloor. Our results indicate that north of Tuktoyaktuk Island, where coastal erosion is considerably faster, IBPT depths range from 5 m below sea level (120 m from the shoreline) to around 20 m b.s.l. (up to 800 m from the shoreline). South of the island, the IBPT dips more steeply and lies at 10 m b.s.l. a few meters from the shore, and 200 m from the shore, it is more than 30 m b.s.l. We discuss how marine ERT can be improved by accurately recording electrode positions, although choices made during data inversion are likely a greater source of uncertainty in the determination of the IBPT position. At Tuktoyaktuk Island, IBPT depths below the seafloor increase with distance from the shoreline; comparing the northern and southern sides of the island, the inclination is inversely proportional to coastline retreat rates. On the island's north side, the historical coastal retreat rate suggests a mean permafrost degradation rate of 5.3 ±4.0 cm yr −1 .Horizon 2020Peer Reviewe
Researching urban diversity and the (re-)production of whiteness: reflections on the purchase and challenges of sensory methods
No full textIn this paper, we reflect on the purchase of sensory methodologies to research urban diversity and the (re-)production of whiteness. In the social sciences, scholars commonly rely on visual methods, using the ‘body as text’ (Stoller, 1997). Based on more recent advances in urban and migration studies, we seek to move beyond this Eurocentric focus, by asking how urban diversity is experienced through sounds and through smells. How individuals experience sensory inputs such as sounds and smells, and how they make sense of them, feeds into processes of boundary making and boundary crossing. The urban space is a prime context to study such processes, given that cities’ dense character and high diversity provide their residents with endless sensory stimuli. Based on sensory research in a highly diverse street in Berlin, we reflect on how smells and sounds contribute to creating hierarchies between (groups of) people, how they contribute to feelings of local belonging and home, or feelings of being out of place. We also reflect on the challenges of applying sensory methods. These refer to the relationship between participants’ embodied experiences and how they made sense of those discursively in group discussions; and about the implications of doing research on a highly mediatized street. With our focus on micro interactions, the (re-) production of space, and diversity, our findings add to the emerging field of ‘sensory urbanism’
The Role of Spatial Dependence in Modelling German Regional Housing Markets and Commuting
No full textZiel dieser Arbeit ist es, die methodischen und empirischen Lücken in der regionalen Analyse des deutschen Wohnungsmarktes und pendeln. Kapitel 1 bietet einen Überblick über räumliche ökonometrische Methoden und Quantilsregressionsmodelle. Kapitel 2 trägt zur Methodik einer räumlichen bedingten Quantilsregression bei. In diesem Kapitel schlage ich ein zweistufiges Schätzverfahren für eine räumliche quantilsregression (SEQM räumliches Error quantilmodell) vor und wende das Verfahren auf regionale Wohnungspreise in deutschen Regionen und eine Mikroanalyse der Wohnungspreise in Madrid an. Die vorgeschlagene Methode wird für die Eigenschaften kleiner Stichproben untersucht und konstruiert die optimale Kombination aus räumlichen Regressions- und Quantilsregressionsmethoden, die der regionalen Heterogenität der Wohnungsmärkte und räumlichen Abhängigkeiten angemessen ist. Kapitel 3 analysiert die Dynamik der Unterschiede zwischen regionalen Wohnungsmärkten in Deutschland. Unter Berücksichtigung der bestehenden räumlichen Muster begründe ich, dass die regionalen Wohnungsmärkte im Zeitraum 2004-2020 eine Konvergenz der regionalen Wohnungspreise erfahren. Kapitel 4 ist der Analyse der Pendlerströme zwischen deutschen Regionen gewidmet. Die Analyse wird mithilfe eines Gravitationsmodells durchgeführt und betrachtet die Wohnungspreise als einen der Hauptdeterminanten des Pendlerverhaltens. Somit bietet die Arbeit eine angemessene räumliche Analyse der regionalen Wohnungsmärkte und des Pendelns in Deutschland und leistet einen Beitrag zur Methodik der räumlichen Quantilmodellierung.The thesis aims to fulfil the methodological and empirical gaps in regional analysis of the German housing markets and commuting. Chapter 1 provides a review of spatial econometric methods and quantile regression models. Chapter 2 contributes to the methodology of a spatial conditional quantile regression. In this chapter, I propose a two-step estimation procedure for a spatial error quantile regression (SEQM - spatial error quantile model) and apply the procedure for the analysis of regional housing prices in Germany. The proposed method is studied for the small sample and asymptotic properties and constructs the optimal combination of spatial regression and quantile regression methods, appropriate for the regional heterogeneity in housing markets and spatial dependences. Chapter 3 is devoted to the analysis of the disparities between regional housing prices in Germany. Taking into account the existing spatial patterns, I justify that regional housing markets experience convergence in regional housing prices in the period from 2004 until 2020. Chapter 4 is devoted to the analysis of commuting flows between German regions. The analysis is performed with the help of a gravity model and considers housing prices as one of the core determinants of the commuting behaviour. Hence, the thesis provides a proper spatial analysis of regional housing markets and commuting in Germany and contributes to the methodology of spatial quantile modelling
Total Cost of Ownership and Evaluation of Google Cloud Resources for the ATLAS Experiment at the LHC
Get PDFThe ATLAS Google Project was established as part of an ongoing evaluation of the use of commercial clouds by the ATLAS Collaboration, in anticipation of the potential future adoption of such resources by WLCG grid sites to fulfil or complement their computing pledges. Seamless integration of Google cloud resources into the worldwide ATLAS distributed computing infrastructure was achieved at large scale and for an extended period of time, and hence cloud resources are shown to be an effective mechanism to provide additional, flexible computing capacity to ATLAS. For the first time a total cost of ownership analysis has been performed, to identify the dominant cost drivers and explore effective mechanisms for cost control. Network usage significantly impacts the costs of certain ATLAS workflows, underscoring the importance of implementing such mechanisms. Resource bursting has been successfully demonstrated, whilst exposing the true cost of this type of activity. A follow-up to the project is underway to investigate methods for improving the integration of cloud resources in data-intensive distributed computing environments and reducing costs related to network connectivity, which represents the primary expense when extensively utilising cloud resources.Open access funding provided by CERN (European Organization for Nuclear Research)CERN (European Organization for Nuclear Research)Peer Reviewe
Causality in the Winter Interaction Between Extratropical Storm Tracks, Atmospheric Circulation, and Arctic Sea Ice Loss
No full textGlobal warming is accelerating the decline of Arctic sea ice, with wide‐ranging impacts on the Earth's climate system. Using ERA5 data from 1980 to 2023, we investigated the relationship between winter extratropical storm tracks, atmospheric circulation patterns, and sea ice area (SIA) in three key Arctic regions. We classified the winters into two categories: atmosphere‐driven winters (ADWs), when atmospheric circulation influences sea ice, and ice‐driven winters (IDWs), when sea ice influences atmospheric circulation. This classification was based on the sign of SIA and surface turbulent heat flux anomalies in the Barents‐Kara Sea (BKS), Baffin Bay, Davis Strait, and Labrador Sea (BDL), and Chukchi‐Bering Seas (CBS). Our findings show that in IDWs, reduced SIA has a minor effect on extratropical storm tracks. However, we observed significant midtropospheric cooling over northeastern Asia, aligning with the effects of reduced ice in the BKS during IDWs. This emphasizes the importance of considering the entire tropospheric temperature profile to capture the impact of sea ice loss. In contrast, during ADWs, the BKS and CBS regions experience amplified surface warming and SIA loss due to storm‐induced intrusion of warm and moist air, with sea ice loss in the BKS contributing to strengthening Ural blocking. Although cyclone‐induced heat and moisture intrusion is prevalent, we found no significant trend in track density or mean intensity of positive V extrema in the North Atlantic sector of the Arctic, suggesting that changes in atmospheric circulation are unlikely to be the driver of recent sea ice loss in the BKS.Plain Language Summary: Global warming is causing Arctic sea ice to shrink, which affects the Earth's climate in many ways. Using ERA5 data from 1980 to 2023, we studied how changes in storm patterns, atmospheric conditions, and sea ice are connected in three Arctic regions. We classified winters into two categories: atmosphere‐driven winters (ADWs), in which atmospheric conditions affect sea ice, and ice‐driven winters (IDWs), in which sea ice influences atmospheric conditions. We found that during IDWs, sea ice loss has only a small effect on storm patterns, but it leads to cooling in the midatmosphere over northeastern Asia. This highlights the need to look at temperature changes throughout the entire atmosphere, not just at the surface. In ADWs, storm‐driven warm, moist air leads to more surface warming and sea ice loss, particularly in the Barents‐Kara Sea, where the sea ice loss also contributes to stronger Ural blocking. Although storms in these regions bring heat and moisture, we did not find a clear trend in the number or intensity of storms, suggesting that changes in atmospheric circulation are not the main cause of recent sea ice loss. This research helps to better understand how Arctic sea ice loss and atmospheric changes are linked.Key Points: Recent cooling trend in northeastern Asia occurs in the midtroposphere, primarily driven by sea ice loss in the Barents‐Kara Sea (BKS). Changes in atmospheric circulation are unlikely to be the primary driver of recent sea ice loss in the BKS. In atmosphere‐driven winters, amplified surface warming in the Barents‐Kara and Chukchi Seas result from storm‐driven warm air advection.Peer Reviewe
Anne-Marie Kilday / David Nash, Beyond Deviant Damsels. Re-evaluating Female Criminality in the Nineteenth Century. Oxford, Oxford University Press 2023
No full textRezensierte Publikation: Anne-Marie Kilday, Beyond Deviant Damsels. Re-evaluating Female Criminality in the Nineteenth Century. 2023 Oxford University Press Oxford, 9780198830733, £ 83,–Peer Reviewe
The perception of fairness in the division of labor around first childbirth in Germany
No full textThe article processing charge was funded by the Open Access Publication Fund of Humboldt-Universität zu Berlin.The transition to parenthood is a pivotal life course event that impacts well-being, relationship quality and the distribution of housework and paid work. In Germany, during the transition to first-time parenthood, women often reduce their involvement in paid work and take on a larger share of housework, leading to a more gendered division of labor. This shift could influence perceptions of fairness in the division of labor inducing both men and women to perceive the division as being more fair to themselves or more fair to their partner. Using data from the German Panel Analysis of Intimate Relationships and Family Dynamics (pairfam) and fixed effects models, we examine how women’s and men’s perception of fairness of the division of labor varies around first childbirth conceptualizing different phases spanning from 5 years before until 5 years after the first childbirth. Relative to baseline, mothers (-to-be) reported a fairer division of labor (less under-benefitting) from around conception to right after childbirth. Yet, already from 6 months after childbirth mothers’ perception of fairness becomes less fair to them again and the perception of under-benefitting continues as the child ages. For fathers-to-be, perceptions of fairness did not vary substantially around childbirth. We further found that neither the change in the division of housework, nor in the division of paid work, explained changes in fairness perceptions during the transition to parenthood.Open Access funding enabled and organized by Projekt DEAL.Riksbankens Jubileumsfondhttp://dx.doi.org/10.13039/501100004472Forskningsrådet om Hälsa, Arbetsliv och Välfärdhttp://dx.doi.org/10.13039/501100006636Humboldt-Universität zu Berlin (1034)Peer Reviewe
A Transfer of Language and Culture: German Bread and Pastries and Their Names in Kosovo
No full textThis article examines the linguistic and cultural influence of German bread culture in Kosovo, where bread holds significant meaning as a symbol of hospitality and community. The introduction of German bread products, driven by migration and economic changes, has transformed Kosovar “bread habits”. The Buka and Premium bakeries have played a crucial role in promoting German bread names and products, capitalising on their perceived prestige and association with healthy eating trends. The article researches German–Albanian relations and shows that there is intensive interaction especially in the area of food. This connection, along with the legacy of its former status as part of Yugoslavia, migration, and the presence of German-speaking institutions in Kosovo, highlights the role of bread as a culinary, language, and cultural link. Using the methodological lens of language and cultural transfer, the study demonstrates the significant influence of German bread culture on Kosovo’s bread-making practices and food culture