Estimating the uptake of traffic-derived NO2 from 15N abundance in Norway spruce needles

The 15N ratio of nitrogen oxides (NOx) emitted from vehicles, measured in the air adjacent to a highway in the Swiss Middle Land, was very high [δ15N(NO2) = +5.7‰]. This high 15N abundance was used to estimate long-term NO2 dry deposition into a forest ecosystem by measuring δ15N in the needles and the soil of potted and autochthonous spruce trees [Picea abies (L.) Karst] exposed to NO2 in a transect orthogonal to the highway. δ15N in the current-year needles of potted trees was 2.0‰ higher than that of the control after 4 months of exposure close to the highway, suggesting a 25% contribution to the N-nutrition of these needles. Needle fall into the pots was prevented by grids placed above the soil, while the continuous decomposition of needle litter below the autochthonous trees over previous years has increased δ15N values in the soil, resulting in parallel gradients of δ15N in soil and needles with distance from the highway. Estimates of NO2 uptake into needles obtained from the δ15N data were significantly correlated with the inputs calculated with a shoot gas exchange model based on a parameterisation widely used in deposition modelling. Therefore, we provide an indication of estimated N inputs to forest ecosystems via dry deposition of NO2 at the receptor level under field conditions

Lineage-specific requirements of β-catenin in neural crest development

β-Catenin plays a pivotal role in cadherin-mediated cell adhesion. Moreover, it is a downstream signaling component of Wnt that controls multiple developmental processes such as cell proliferation, apoptosis, and fate decisions. To study the role of β-catenin in neural crest development, we used the Cre/loxP system to ablate β-catenin specifically in neural crest stem cells. Although several neural crest–derived structures develop normally, mutant animals lack melanocytes and dorsal root ganglia (DRG). In vivo and in vitro analyses revealed that mutant neural crest cells emigrate but fail to generate an early wave of sensory neurogenesis that is normally marked by the transcription factor neurogenin (ngn) 2. This indicates a role of β-catenin in premigratory or early migratory neural crest and points to heterogeneity of neural crest cells at the earliest stages of crest development. In addition, migratory neural crest cells lateral to the neural tube do not aggregate to form DRG and are unable to produce a later wave of sensory neurogenesis usually marked by the transcription factor ngn1. We propose that the requirement of β-catenin for the specification of melanocytes and sensory neuronal lineages reflects roles of β-catenin both in Wnt signaling and in mediating cell–cell interactions

AMP Is a True Physiological Regulator of AMP-Activated Protein Kinase by Both Allosteric Activation and Enhancing Net Phosphorylation

SummaryWhile allosteric activation of AMPK is triggered only by AMP, binding of both ADP and AMP has been reported to promote phosphorylation and inhibit dephosphorylation at Thr172. Because cellular concentrations of ADP and ATP are higher than AMP, it has been proposed that ADP is the physiological signal that promotes phosphorylation and that allosteric activation is not significant in vivo. However, we report that: AMP is 10-fold more potent than ADP in inhibiting Thr172 dephosphorylation; only AMP enhances LKB1-induced Thr172 phosphorylation; and AMP can cause >10-fold allosteric activation even at concentrations 1–2 orders of magnitude lower than ATP. We also provide evidence that allosteric activation by AMP can cause increased phosphorylation of acetyl-CoA carboxylase in intact cells under conditions in which there is no change in Thr172 phosphorylation. Thus, AMP is a true physiological regulator of AMPK, and allosteric regulation is an important component of the overall activation mechanism

Do residential preferences foster sprawl in upstate New York?

Rural New York Minute, Issue 1

International Social Survey Programme 1999 (Switzerland)

Die Studie ist Teil einer international vergleichenden Studie (vgl. ZA-Studien-Nr. 3430

Big Data in the Insurance Industry: Leeway and Limits for Individualising Insurance Contracts

With the advent of big data analytics, the individualisation of mass market insurance policies has become commercially attractive. While this development would have positive economic effects, it could also undermine the principle of solidarity in insurance. This paper aims to outline the different regulatory approaches currently in place for dealing with this fundamental challenge by analysing the insurance, anti-discrimination and data protection laws of Switzerland and the U.S./California pertaining to health, renters and automobile insurance. It will be shown that the leeway for individualising insurance contracts is vanishingly small for (mandatory) health insurance on both sides of the Atlantic. By contrast, the two legal systems pursue different regulatory approaches with regard to the other two types of insurance. Renters and automobile insurance are predominantly governed by the freedom of contract principle in Switzerland, whereas in California sector specific regulations significantly limit the informational basis of insurance companies, thereby limiting the leeway for individualisation to a large extent. While Swiss anti-discrimination law hardly restricts the individualisation of insurance contracts, U.S. and California law prohibit such individualisation based on protected characteristics, in this way further restricting the remaining leeway. While privacy laws in the U.S. and California set some significant but rather specific limits for the individualisation of insurance contracts based on the use of personal data, the all-encompassing Swiss (and European) data protection law is clearly the most important barrier to individualisation in Switzerland. Namely, it remains unclear whether the processing of personal data for the purpose of individualising insurance contracts may be based on the legitimate interests of the insurer. As a consequence, insurance companies are advised to always obtain their customers’ consent for making individual offers based on big data analytics. The authors conclude that instead of indirectly hindering the individualisation of insurance contracts through data protection law, Swiss (and European) lawmakers should initiate a dialogue involving all stakeholders to determine which sectors of insurance should be dominated by the principle of solidarity and in which sectors and on what informational basis the individualisation of insurance contracts should be allowed

The Changing Nature of Housing Markets in Upstate New York

The rapid rate of land development across the US. leads to what is commonly referred to as residential sprawl. This article reviewed issues related to rural residential sprawl and the forces behind it, including the role of home buyer preferences. A sample of 63,196 home sale transactions that occurred between 1998 and 2005 in the Rochester, New York housing market comprised the data set for a hedonic pricing analysis that included open space variables within the vectors of housing characteristics. Results from the analysis indicated that household preferences for more living space, site acreage, and proximity to open space were among the driving forces for residential sprawl in this housing market