Revisiting Strategic versus Non-Strategic Cooperation

We use a novel experimental design to disentangle strategically- and non-strategically-motivated cooperation. By using contingent responses in a repeated sequential prisoners’ dilemma with a known probabilistic end, we differentiate end-game behavior from continuation behavior within individuals while controlling for expectations. This design allows us to determine the extent to which strategically-cooperating individuals are responsible for the so-called endgame effect. Experiments with two different subject pools indicate that the most common motive for cooperation in repeated games is strategic and that the extent to which endgame effects are driven by strategically-cooperating individuals depends on the profitability of cooperation.

The Physics of the B Factories

This work is on the Physics of the B Factories. Part A of this book contains a brief description of the SLAC and KEK B Factories as well as their detectors, BaBar and Belle, and data taking related issues. Part B discusses tools and methods used by the experiments in order to obtain results. The results themselves can be found in Part C

Role of five synthetic reaction conditions on the stable isotopic composition of 3,4-methylenedioxymethamphetamine

The identification of links between seizures of illicit 3,4- methylenedioxymethamphetamine (MDMA or 'ecstasy') has been a global target of law enforcement agencies in recent years. Previous work has shown that, when the reaction conditions are carefully repeated from batch to batch, stable isotope ratios allow the discrimination of MDMA· HCl batches according to synthetic route used for manufacture. In this study, the effects of altering five reaction conditions relating to the Pt/H2 reductive amination synthesis were, for the first time, systematically investigated using a two level, five factor factorial design. Results indicate that the δ2H values of MDMA· HCl are affected by the length of imine stir time, and the δ15N values are affected by the degree of excess methylamine employed. Furthermore, the δ13C and δ18O values have been shown to be affected by the efficiency of the reaction, despite the similarity in carbon and oxygen composition of the starting material and product molecules. In addition to being of theoreticalimportance in this field of analytical science overall, this work is essential in order to more fully contextualize the interpretation of IRMS data which may be used as potential forensic evidence