Learning Options in Reinforcement Learning

Temporally extended actions (e.g., macro actions) have proven very useful in speeding up learning, ensuring robustness and building prior knowledge into AI systems. The options framework (Precup, 2000; Sutton, Precup & Singh, 1999) provides a natural way of incorporating such actions into reinforcement learning systems, but leaves open the issue of how good options might be identified

Investigating the function of Pre-Pottery Neolithic stone troughs from Göbekli Tepe – An integrated approach.

An integrated approach using contextual, use-wear, scientific and experimental methods was used to analyze the role of stone troughs of up to 165 l capacity at the Early Neolithic site Göbekli Tepe in the context of other stone containers found there. Around 600 (mostly fragmentary) vessels from the site constitute the largest known assemblage from the Pre-Pottery Neolithic of the Near East. Besides the large limestone troughs, it encompasses middle-sized, coarsely made limestone vessels, finely executed platters and ‘greenstone’ vessels. All lines of evidence taken together indicate the use of limestone troughs for the cooking of cereals

A biomolecular archaeological approach to ‘Nordic grog’

The combined archaeological, biomolecular, and archaeobotanical evidence from four sites in Denmark (Nandrup, Kostræde, and Juellinge) and Sweden (Havor on the island of Gotland) provide key reference points for reconstructing ‘Nordic grog’ from ca. 1500 BC to the first century AD. In general, Nordic peoples preferred a hybrid beverage or ‘grog,’ in which many ingredients were fermented together, including locally available honey, local fruit (e.g., bog cranberry, and lingonberry) and cereals (wheat, rye, and/or barley), and sometimes grape wine imported from farther south in Europe. Local herbs/spices, such as bog myrtle, yarrow and juniper, and birch tree resin rounded out the concoction and provide the earliest chemical attestations for their use in Nordic fermented beverages. The aggregate ingredients probably served medicinal purposes, as well as contributing special flavors and aromas. They continued to be important ingredients for many kinds of beverages throughout medieval times and up to the present. The importation of grape wine from southern or central Europe as early as ca. 1100 BC, again chemically attested here for the first time, is of considerable cultural significance. It demonstrates the social and ceremonial prestige attached to wine, especially when it was served up as ‘Nordic grog’ in special wine-sets imported from the south. It also points to an active trading network across Europe as early as the Bronze Age in which amber might have been the principle good exchanged for wine. The presence of pine resin in the beverages likely derives from the imported wine, added as a preservative for its long journey northward

Chloroplast microsatellites to investigate the origin of grapevine

The origin of the grapevine, Vitis vinifera L. (ssp.) sativa has been investigated with archaeobotanical–archaeological, cultural and historical data indicating a unique domestication centre located in the Caucasianand Middel-East regions about 6–7000 years ago, but, events leading to the domestication of thisspecies are still an open issue. In this work, eight universal chloroplast microsatellites are used to assessgenetic relationships among varieties selected as representatives of four distinct geographical groups fromMiddle-East to Western European regions. Results show that two out of the eight analysed chloroplast lociare polymorphic within the 142 individuals. Allele variants of the cpSSR loci combine in a total of sixdifferent haplotypes. The analysis of haplotypes distribution and haplotype diversity (HD) suggest that onlythree out of the six haplotypes are represented in the Caucasian and Middle-East samples, with 90% ofindividuals sharing the same haplotype. Moreover, the presence of all six haplotypes in the Europeanaccessions, with a high level of haplotype diversity, suggests varietal influx in these areas. Concerning theWestern European varieties, especially in Spanish accessions, half of the individuals share haplotype VIwhich is completely absent in the Caucasian and Middle-East cultivars. This result opens the discussionabout the existence of a unique and common domestication centre, located in the Caucasian and Middle-East area, for all the European cultivars.This work suggests the usefulness of chloroplast genome markers to provide information on haplotypedistributions that could help to identify further geographical areas for grapevine varietal evolution