Die Deutschlandreise des René Descartes

Due to lacking reliable sources almost no details were available on the educational journey of the joung Descartes. Moreover, contradictions in several publications resulted in the doubt, whether these events, which are so important for the history of science, ever hapened at all. Folowing careful and comprehensive research at the City Archives Ulm, the Hessian City Archives Darmstadt and the Bavarian State Library in Munich the author found evidence that René Descartes met the mathematician and master fortress builder Johann Faulhaber in Ulm.¹ Now, the first summary of Descartes' travel report can be given based on further findings (in reliable sources) and corroborated by numerous facts.     

Mobility or migration: a case study from the Neolithic settlement of Nieder-Mörlen (Hessen,Germany)

A combination of stable carbon and nitrogen isotope analysis of collagen and radiogenic strontium isotope analysis of tooth enamel was used to investigate diet and mobility at the early Neolithic settlement of Nieder-Mörlen in Germany. The carbon and nitrogen ratios suggest a mixed terrestrial based diet that is consistent with data previously published for early Neolithic sites in Europe. The strontium isotope data indicate a high degree of human mobility with only one individual having an isotope ratio consistent with locally derived strontium. Unusually, a group of non-local juveniles with isotope ratios typical of upland regions is also present at the settlement but there are no adult burials with such values. Whilst transhumance is considered as an explanation, it would not explain why these non-local juveniles lived foreshortened lives and other possible mechanisms are therefore discussed.     

11月投奔新雪国

新雪国滑雪场关键词：2014年年底开业2014～2015年雪季,位于河北省张家口市赤城县的新雪国滑雪场将盛装启幕,这是一座建成后有能力承办世界顶级滑雪赛事的洲际滑雪胜地。可在3180米长度内实现801米落差的奥林匹克标准的雪道将迎来第一批世界各地滑雪爱好者的免费试滑体验,当雪友们好吸着新雪国新鲜的空气,踏上雪板的那一划,这片雪域也将被点燃速度与激情。     

温婉如水 忧郁如河

如同Johannes Vermeer的画作一般,代尔夫特至今容颜未改：古老的运河、拱形的石桥、宁静的田园以及美丽的市集广场,在每一个晨昏,陷入一片古朴厚重得色调之中,温婉如水、忧郁如河。     

Duopoly prices under congested access*

Abstract. Consider two firms, at different locations, supplying a homogenous good at constant marginal production cost. Consumers incur travel costs to the firm for each unit purchased, and the travel costs increase with the amount of travel to each firm (congestion). When all traffic and all congestion are generated by travel to a duopolist, both the Nash–Bertrand equilibrium prices and the Nash–Cournot equilibrium prices exceed the sum of the marginal production cost and the marginal external travel cost. However, when the road is shared by travelers to the duopolists' facilities and travelers in competitive markets, the Nash–Bertrand duopoly price equals the competitive price and the Nash–Cournot price contains a markup.