Dynamic asset allocation and latent variables

We derive an explicit solution to the portfolio problem of a power utility investor with preferences for wealth at a ¯nite investment horizon. The investor can invest in assets with return dynamics described as part of a general multivariate model. The modeling framework encompasses discrete-time VAR-models where some of the state-variables (e.g. expected excess returns) may not be directly observable. A realistic multivariate model is estimated and applied to analyze the portfolio implications of investment horizon and return predictability when real interest rates and expected excess returns on stock and bonds are not directly observed but must be estimated as part of the problem faced by the investor. The solution exhibits small variability in portfolio allocations over time compared to the case when excess returns are assumed observable. JEL Classification: G11 Keywords: Portfolio choice, predictability, VAR, unobserved state-variables, hedging demand

The biomolecular characterization of a finger ring contextually dated to the emergence of the Early Neolithic from Syltholm, Denmark.

We present the analysis of an osseous finger ring from a predominantly early Neolithic context in Denmark. To characterize the artefact and identify the raw material used for its manufacture, we performed micro-computed tomography scanning, zooarchaeology by mass spectrometry (ZooMS) peptide mass fingerprinting, as well as protein sequencing by liquid chromatography tandem mass spectrometry (LC-MS/MS). We conclude that the ring was made from long bone or antler due to the presence of osteons (Haversian canals). Subsequent ZooMS analysis of collagen I and II indicated that it was made from Alces alces or Cervus elaphus material. We then used LC-MS/MS analysis to refine our species identification, confirming that the ring was made from Cervus elaphus, and to examine the rest of the proteome. This study demonstrates the potential of ancient proteomics for species identification of prehistoric artefacts made from osseous material

Exploring, exploiting and evolving diversity of aquatic ecosystem models: A community perspective

Here, we present a community perspective on how to explore, exploit and evolve the diversity in aquatic ecosystem models. These models play an important role in understanding the functioning of aquatic ecosystems, filling in observation gaps and developing effective strategies for water quality management. In this spirit, numerous models have been developed since the 1970s. We set off to explore model diversity by making an inventory among 42 aquatic ecosystem modellers, by categorizing the resulting set of models and by analysing them for diversity. We then focus on how to exploit model diversity by comparing and combining different aspects of existing models. Finally, we discuss how model diversity came about in the past and could evolve in the future. Throughout our study, we use analogies from biodiversity research to analyse and interpret model diversity. We recommend to make models publicly available through open-source policies, to standardize documentation and technical implementation of models, and to compare models through ensemble modelling and interdisciplinary approaches. We end with our perspective on how the field of aquatic ecosystem modelling might develop in the next 5–10 years. To strive for clarity and to improve readability for non-modellers, we include a glossary

Dynamic asset allocation and latent variables

We derive an explicit solution to the portfolio problem of a power utility investor with preferences for wealth at a ¯nite investment horizon. The investor can invest in assets with return dynamics described as part of a general multivariate model. The modeling framework encompasses discrete-time VAR-models where some of the state-variables (e.g. expected excess returns) may not be directly observable. A realistic multivariate model is estimated and applied to analyze the portfolio implications of investment horizon and return predictability when real interest rates and expected excess returns on stock and bonds are not directly observed but must be estimated as part of the problem faced by the investor. The solution exhibits small variability in portfolio allocations over time compared to the case when excess returns are assumed observable.Portfolio choice; predictability; VAR; unobserved state-variables; hedging demands

Formation of trioctylamine from octylamine on Au(111)

The adsorption of octylamine on Au(111) under ultrahigh vacuum conditions is investigated. The molecules surprisingly undergo a thermally activated chemical reaction, resulting in formation of trioctylamine as confirmed both by X-ray photoelectron spectroscopy (XPS) and by comparison to the scanning tunneling microscopy (STM) signature of trioctylamine deposited directly onto the surface

Limited historical admixture between European wildcats and domestic cats

Domestic cats were derived from the Near Eastern wildcat (Felis lybica), after which they dispersed with people into Europe. As they did so, it is possible that they interbred with the indigenous population of European wildcats (Felis silvestris). Gene flow between incoming domestic animals and closely related indigenous wild species has been previously demonstrated in other taxa, including pigs, sheep, goats, bees, chickens, and cattle. In the case of cats, a lack of nuclear, genome-wide data, particularly from Near Eastern wildcats, has made it difficult to either detect or quantify this possibility. To address these issues, we generated 75 ancient mitochondrial genomes, 14 ancient nuclear genomes, and 31 modern nuclear genomes from European and Near Eastern wildcats. Our results demonstrate that despite cohabitating for at least 2,000 years on the European mainland and in Britain, most modern domestic cats possessed less than 10% of their ancestry from European wildcats, and ancient European wildcats possessed little to no ancestry from domestic cats. The antiquity and strength of this reproductive isolation between introduced domestic cats and local wildcats was likely the result of behavioral and ecological differences. Intriguingly, this long-lasting reproductive isolation is currently being eroded in parts of the species' distribution as a result of anthropogenic activities