Parallels between experimental and field arbuscular mycorrhizal fungal communities in response to habitat structure

Arbuscular mycorrhizal (AM) fungi have gained immense research interest due to their symbiotic relation with roots of most terrestrial land plants. Diverse positive effects on plant health and fitness, as well as a high ecological relevance for many other below-and aboveground processes have been recognized. Despite growing research ambitions, sufficient knowledge on drivers and their relative impacts on AM fungal communities at varying scales and ecosystems is lacking. Very little attention has been paid to the interrelation of the spatial structure of AM host plants (here meaning the small- scale distribution of host plant individuals or populations) and AM fungal community dynamics, although deeper insights could move forward the development of theoretical community frameworks applicable to these important endosymbionts. The work presented in this thesis aimed to study the effects of host plant spatial structure for the establishment of mycorrhizal symbiosis as well as for AM fungal diversity and community composition. To do so, controlled experiments mimicking micro- landscapes of AM fungal habitats were conducted and compared with observational data from temperate forests in Germany. In the experiments, we used meta-community designs to test the responses of root colonization, AM fungal diversity and community composition to levels of habitat connectance or habitat heterogeneity. We assayed rates of root colonization across forests sites differing in AM-associating plant cover. For assessing the importance of further spatio-temporal parameters and host-specificity we surveyed AM fungal communities within one of the forest sites over two years. As expected, we observed a consistent pattern of higher rates of root colonization at a higher proximity of host plants, which in the case of the field study was a higher cover of AM- associating woody plants and in the case of the experiment treatments a higher connectance of host plant patches. There were generally no clear effects of habitat structure on AM fungal diversity and community composition in both the field and the experimental study. In the field, the main finding was that spatial parameters, followed by host identity, more strongly affected AM fungal assemblages than temporal parameters. In the experiments, we observed within-experimental-unit differences of beta-diversity between pairs of long- and short-distance patches as well as between pairs of different habitat quality, which rendered those communities less predictable. In conclusion, we present empirical evidence for a co-variation of AM plant host structure and AM fungal abundance. These findings are of importance for the restoration or management of natural forest habitats, as well as for sustainable agriculture. Furthermore, this work supports previous findings of high stochasticity in AM fungal communities, highlighting the need for further research into spatial scale-specific drivers of this important organism group

Steering is an essential feature of non-locality in quantum theory

A physical theory is called non-local when observers can produce instantaneous effects over distant systems. Non-local theories rely on two fundamental effects: local uncertainty relations and steering of physical states at a distance. In quantum mechanics, the former one dominates the other in a well-known class of non-local games known as XOR games. In particular, optimal quantum strategies for XOR games are completely determined by the uncertainty principle alone. This breakthrough result has yielded the fundamental open question whether optimal quantum strategies are always restricted by local uncertainty principles, with entanglement-based steering playing no role. In this work, we provide a negative answer to the question, showing that both steering and uncertainty relations play a fundamental role in determining optimal quantum strategies for non-local games. Our theoretical findings are supported by an experimental implementation with entangled photons.Comment: 16 pages, 5 figure

Technology Spillovers: A Motive for Foreign Direct Investment?

This paper explores the relationship between the R&D activity in a country and the inflow of foreign capital through foreign direct investment and foreign ownership. The idea that firms invest abroad in order to more easily absorb the knowledge and technology of foreign firms is tested empirically using a unique firm level data set covering foreign ownership and R&D in all Norwegian manufacturing firms over the period 1990 to 1996. The study gives no clear support for such a motive behind foreign ownership. On the contrary, the econometric study indicates that foreign investors predominantly try to exploit their technological advantages in the Norwegian market. The results also show that the presence of foreign ownership is more volatile in highly R&D intensive firms. We claim that this is due to the fact that large R&D investment often result in large losses as well as gains, which again attracts or repels foreign owner interests.

Inward FDI in Norway and its policy context

Norwegian inward foreign direct investment (IFDI) has increased rapidly since 2000. A stock of US$30 billion in 2000 grew by almost 300$ 116 billion by 2009, a growth stronger than that of most other OECD member countries. The development of Norwegian IFDI has been rather uneven, with stable periods punctuated by boom years. IFDI in 2008 was lower than in 2007, partly reflecting the cooling down of the world economy as a result of the international financial and economic crisis. The latest available data indicate that IFDI remained in a slump in 2009. The composition of Norwegian IFDI largely follows the structure of Norway's private-sector economy, with a clear dominance of the oil and gas sector. The manufacturing sector is gradually losing its appeal to foreign investors, although more slowly than one would expect considering the reduced importance of this sector in the Norwegian economy

A Lens for Evaluating Genetic Information Governance Models:Balancing Equity, Efficiency and Sustainability

This paper draws from the literature on collective action and the governance of the commons to address the governance of genetic data on variants of specific genes. Specifically, the data arrangements under study relate to the BRCA genes (BRCA1 and BRCA2) which are linked to breast and ovarian cancer. These data are stored in global genetic data repositories and accessed by researchers and clinicians, from both public and private institutions. The current BRCA data arrangements are fragmented and politicized as there are multiple tensions around data ownership and sharing. Three key principles are proposed for forming and evaluating data governance arrangements in the field. These principles are: equity, efficiency and sustainability