Dissimilar metals friction welding of austenitic–martensitic stainless steels is commonly used in order to manufacture engine valves in the automobile industry. In this study, X53CrMnNiN219 (austenitic stainless steel) and X45CrSi93 (martensitic stainless steel) valve steel rods were welded by friction welding process. The welded joint was then heat treated at 760 0C for 60 min. Mechanical prop...

A digraph D = (V, A) is arc-traceable if for each arc xy in A, xy lies on a directed path containing all the vertices of V , i.e., hamiltonian path. We prove a conjecture of Quintas [7]: if D is arc-traceable, then the condensation of D is a directed path. We show that the converse of this conjecture is false by providing an example of an upset tournament which is not arc-traceable. We then giv...

Developmental gene expression results from the orchestrated interplay between genetic and epigenetic mechanisms. Here, we describe upSET, a transcriptional regulator encoding a SET domain-containing protein recruited to active and inducible genes in Drosophila. However, unlike other Drosophila SET proteins associated with gene transcription, UpSET is part of an Rpd3/Sin3-containing complex that...

BACKGROUND International travellers are at a risk of infectious diseases not seen in their home country. Stomach upsets are common in travellers, including on cruise ships. This study compares the incidence of stomach upsets on land- and cruise-based holidays. METHODS A major British tour operator has administered a Customer Satisfaction Questionnaire (CSQ) to UK resident travellers aged 16 o...