Quantifying Land Use Regulation and its Determinants - Ease of Residential Development across Swiss Municipalities

We analyze land use regulation and the determinants thereof across the majority of Swiss municipalities. Based on a comprehensive survey, we construct several indices on the ease of local residential development, which capture various aspects of local regulation and land use coordination across jurisdictions. The indices provide harmonized information about what local regulation entails and the local regulatory environment across municipalities. Our analysis shows that, among others, historical building density, socio-demographic factors, local taxes, cultural aspects, and the quality of natural amenities are important determinants of local land-use regulation. We test the validity of the index with regard to information about the local refusal rates of development projects and show that the index captures a significant part of the variation in local housing supply elasticities. Based on a machine learning cross-validation model, we impute the values for non-responding municipalities

Place-based policies and spatial disparities across European cities

Spatial disparities in income levels and worklessness in the European Union are profound, persistent and may be widening. We describe disparities across metropolitan regions and discuss theories and empirical evidence that help us understand what causes these disparities. Increases in the productivity benefits of cities, the clustering of highly educated workers and increases in their wage premium all play a role. Europe has a long-standing tradition of using capital subsidies, enterprise zones, transport investments and other place-based policies to address these disparities. The evidence suggests these policies may have partially offset increasing disparities but are not sufficient to fully offset the economic forces at work

Spatial frictions in consumption and retail competition

In this paper, we empirically quantify spatial consumption frictions and the degree of local retail competition. We exploit a unique data set including 1.5 billion daily transactions in combination with detailed characteristics of more than 3 million households. Our estimates are based on a quasi-experimental approach to estimate the causal effect of store openings. We find that a same-chain store opening in the proximity of households' residences reduces their expenditures at incumbent stores by 30% in the first month. Smaller effects for competitors suggest imperfect substitutability between retail chains. Exploiting more than 350 openings, we identify causal consumption gravity functions, which allow us to quantify spatial consumption areas. We document significant heterogeneities across regions and socio-demographic groups, indicating substantial inequalities in consumption access

The amplifying effect of capitalization rates on housing supply

We provide empirical evidence that increases in housing rental income lead to a larger supply response than price increases of the same percentage value. We rationalize this differential in supply responsiveness with an amplification mechanism arising from a downward revision of capitalization rates following a rental income increase. We document that the amplification of the housing supply price elasticity is less pronounced in geographically constrained and tightly regulated neighborhoods and areas having more sophisticated investors. Our findings hold valuable lessons for public policies affecting the housing rental income, such as rent control and housing subsidies

The Fragility of Urban Social Networks - Mobility as a City Glue -

Social interactions are crucial to a city's cohesion, and the high frequency of interaction reflects many benefits of density. However, adverse environmental conditions, such as pollution or pandemics, may critically affect these interactions as they shift preferences over meeting locations and partners. Some interactions may be shifted to the virtual space, while other non-planned interactions may disappear. We analyze spatial interaction networks in Singapore covering about half of the adult population at a fine-grained spatial resolution to understand the importance of population mixing and places' amenities for urban network resilience. We document that environmental shocks negatively affect total interactions. Still, conditional on meeting physically, the number and type of location options may crucially impact the intensity and type of social interactions. The interplay between preferences for meetings partners, locations, and mobility determines population mixing and the fragility of urban social networks

Nucleosomal arrangement affects single-molecule transcription dynamics.

In eukaryotes, gene expression depends on chromatin organization. However, how chromatin affects the transcription dynamics of individual RNA polymerases has remained elusive. Here, we use dual trap optical tweezers to study single yeast RNA polymerase II (Pol II) molecules transcribing along a DNA template with two nucleosomes. The slowdown and the changes in pausing behavior within the nucleosomal region allow us to determine a drift coefficient, χ, which characterizes the ability of the enzyme to recover from a nucleosomal backtrack. Notably, χ can be used to predict the probability to pass the first nucleosome. Importantly, the presence of a second nucleosome changes χ in a manner that depends on the spacing between the two nucleosomes, as well as on their rotational arrangement on the helical DNA molecule. Our results indicate that the ability of Pol II to pass the first nucleosome is increased when the next nucleosome is turned away from the first one to face the opposite side of the DNA template. These findings help to rationalize how chromatin arrangement affects Pol II transcription dynamics

Nanostructural organization of naturally occurring composites - part II: silica-chitin-based biocomposites

Investigations of the micro- and nanostructures and chemical composition of the sponge skeletons as examples for natural structural biocomposites are of fundamental scientific relevance. Recently, we show that some demosponges (Verongula gigantea, Aplysina sp.) and glass sponges (Farrea occa, Euplectella aspergillum) possess chitin as a component of their skeletons. The main practical approach we used for chitin isolation was based on alkali treatment of corresponding external layers of spicules sponge material with the aim of obtaining alkali-resistant compounds for detailed analysis. Here, we present a detailed study of the structural and physicochemical properties of spicules of the glass sponge Rossella fibulata. The structural similarity of chitin derived from this sponge to invertebrate alpha chitin has been confirmed by us unambiguously using physicochemical and biochemical methods. This is the first report of a silica-chitin composite biomaterial found in Rossella species. Finally, the present work includes a discussion related to strategies for the practical application of silica-chitin-based composites as biomaterials

Evidence for a Role of Oxidative Stress in the Carcinogenicity of Ochratoxin A

The in vitro and in vivo evidence compatible with a role for oxidative stress in OTA carcinogenicity has been collected and described. Several potential oxido-reduction mechanisms have been identified in the past. More recently, the possibility of a reduction of cellular antioxidant defense has been raised as an indirect source of oxidative stress. Consequences resulting from the production of oxidative stress are observed at different levels. First, OTA exposure has been associated with increased levels of oxidative DNA, lipid, and protein damage. Second, various biological processes known to be mobilized under oxidative stress were shown to be altered by OTA. These effects have been observed in both in vitro and in vivo test systems. In vivo, active doses were often within doses documented to induce renal tumors in rats. In conclusion, the evidence for the induction of an oxidative stress response resulting from OTA exposure can be considered strong. Because the contribution of the oxidative stress response in the development of cancers is well established, a role in OTA carcinogenicity is plausible. Altogether, the data reviewed above support the application of a threshold-based approach to establish safe level of dietary human exposure to OTA