In this study, high-carbon, chromium alloy steel (100Cr6) having the initial spheroidized microstructure was welded using the rotary friction welding method. The effects of process parameters such as friction time and friction force were experimentally investigated. The friction welded joints were produced of two 100Cr6 steel rods. In order to examine the microstructure and mechanical properti...

We study a model of network formation where the bene…ts from connections exhibit decreasing returns and decay with network distance. We show that the unique equilibrium network is a periphery-sponsored star, where one player, the center, maintains no links and earns a high payo¤, while all other players maintain a single link to the center and earn lower payo¤s. Both the star architecture and p...

Yeast mother cells pay a sacrifice during budding: they keep the extrachromosomal rDNA circles (ERCs) so that their buds have a full lifespan ahead. Two new studies indicate that retention of ERCs in mother cells occurs not by tethering to the nuclear periphery but rather by the simple rules of diffusion in a time-limited and complex landscape.

The most salient feature of the spatial economy is the presence of a large variety of economic agglomerations. Our purpose is to review some of the main explanations of this universal phenomenon, as they are proposed in urban economics and modern economic geography. Because of space constraints, we restrict ourselves to the most recent contributions, referring the reader to our forthcoming book...

A new map of the SNR G78.2+2.1 at 232 MHz is presented. This map is used with other images at 408, 1420, 2695 and 4800 MHz to investigate the total spectral index of the SNR and the variation of spectral index across it. The integrated spectral index is α = 0.54 ± 0.02 (where S ν ∝ ν −α). Maps of the spectral-index variation across the source are derived using a method which calculates a differ...