Changes in sulfhydryl groups of honeybee glyceraldehyde phosphate dehydrogenase associated with generation of the intermediate plateau in its saturation kinetics

Honeybee and rabbit muscle GPDH were studied to obtain information at the chemical level regarding anomolous saturation kinetics of the honeybee enzyme. Results demonstrate that the enzyme's sulfhydryl groups are implicated in the process. Measured by DTNB titration, native honeybee GPDH has one less active SH than the native rabbit muscle enzyme and displays changes in overall sulfhydryl reactivity after preincubation with G-3-P or G-3-P plus NAD+. The total DTNB reactive sulfhydryls of rabbit muscle GPDH are not changed by preincubation with NAD+ or G-3-P; honeybee GPDH, under certain conductions of preincubation with these ligands, shows a decrease of two total DTNB reactive SH groups. This difference has been confirmed by an independent experiment in which the two enzymes were carboxymethylated with C-14 bromoacetic acid

Generalization of the Zlámal condition for simplicial finite elements in ℝ d

The famous Zlámal's minimum angle condition has been widely used for construction of a regular family of triangulations (containing nondegenerating triangles) as well as in convergence proofs for the finite element method in 2d. In this paper we present and discuss its generalization to simplicial partitions in any space dimension

Forward induction and entry deterrence: an experiment

The Dixit (Econ J 90:95–106, 1980) hypothesis that incumbents use investment in capacity to deter potential entrants has found little empirical support. Bagwell and Ramey (J Econ 27:660–680, 1996) propose a model where, in the unique game-theoretic prediction based on forward induction or iterated elimination of weakly-dominated strategies, the incumbent does not have the strategic advantage. We conduct an experiment with games inspired by these models. In the Dixit-style game, the incumbent monopolizes the market most of the time even without the investment in capacity. In our Bagwell-and-Ramey-style game, the incumbent also tends to keep the market, in contrast to the predictions of an entrant advantage. Nevertheless, we fin strong evidence that forward induction affects the behavior of most participants. The results of our games suggest that players perceive that the firs mover has an advantage without having to pre-commit capacity. In our Bagwell–Ramey game, evolution and learning do not drive out this perception. We back these claims with data analysis and a theoretical framework for dynamics.Publicad

Communication, Leadership and Coordination Failure

Using experimental methods, this paper investigates the limits of communication and leadership in aiding group coordination in a minimum effort game. Choosing the highest effort is the payoff dominant Nash equilibrium in this game, and communication and leadership are expected to help in coordinating on such an equilibrium. We consider an environment in which the benefits of coordination are low compared to the cost of mis-coordination. In this environment, players converge to the most inefficient equilibrium in the absence of a leader. We look at two types of leaders: a cheap-talk leader-communicator who suggests an effort level but is free to choose a different level from the one suggested, and a first-mover leader whose choice of effort is observed by the rest of the group. We study whether leadership can prevent coordination failure and whether leadership allows coordination on a higher effort after a history of coordination failure. We find that in this tough environment both types of leadership are insufficient to escape from the low-effort equilibrium but leadership has some (limited) ability to prevent coordination failure. With the help of the strategy method for the followers' responses we find that the main reason for the persistence of coordination failure in this environment is the presence of followers who do not follow (or would not have followed) the leader

Accidental Outcomes Guide Punishment in a “Trembling Hand” Game

How do people respond to others' accidental behaviors? Reward and punishment for an accident might depend on the actor's intentions, or instead on the unintended outcomes she brings about. Yet, existing paradigms in experimental economics do not include the possibility of accidental monetary allocations. We explore the balance of outcomes and intentions in a two-player economic game where monetary allocations are made with a “trembling hand”: that is, intentions and outcomes are sometimes mismatched. Player 1 allocates $10 between herself and Player 2 by rolling one of three dice. One die has a high probability of a selfish outcome, another has a high probability of a fair outcome, and the third has a high probability of a generous outcome. Based on Player 1's choice of die, Player 2 can infer her intentions. However, any of the three die can yield any of the three possible outcomes. Player 2 is given the opportunity to respond to Player 1's allocation by adding to or subtracting from Player 1's payoff. We find that Player 2's responses are influenced substantially by the accidental outcome of Player 1's roll of the die. Comparison to control conditions suggests that in contexts where the allocation is at least partially under the control of Player 1, Player 2 will punish Player 1 accountable for unintentional negative outcomes. In addition, Player 2's responses are influenced by Player 1's intention. However, Player 2 tends to modulate his responses substantially more for selfish intentions than for generous intentions. This novel economic game provides new insight into the psychological mechanisms underlying social preferences for fairness and retribution

Multiple openings and competitiveness of forward markets: experimental evidence

We test the competition enhancing effect of selling forward in experimental Cournot duopoly and quadropoly with multiple forward markets. We find that having two forward periods yields competitive outcomes and that the results are very close to the predicted theoretical results for both quantity setting duopolies and quadropolies. Our experiments lend strong support to the hypothesis that forward markets are competition enhancing. We then test a new market that allows for endogenously determined indefinitely many forward periods that only close when sellers coordinate on selling a zero amount in a forward market. We find that the outcomes under an endogenous close rule are also very competitive. These results hold for both duopolies and quadropolies

Preimplantation genetic testing for Neurofibromatosis type 1:more than 20 years of clinical experience

Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder that affects the skin and the nervous system. The condition is completely penetrant with extreme clinical variability, resulting in unpredictable manifestations in affected offspring, complicating reproductive decision-making. One of the reproductive options to prevent the birth of affected offspring is preimplantation genetic testing (PGT). We performed a retrospective review of the medical files of all couples (n = 140) referred to the Dutch PGT expert center with the indication NF1 between January 1997 and January 2020. Of the couples considering PGT, 43 opted out and 15 were not eligible because of failure to identify the underlying genetic defect or unmet criteria for in vitro fertilization (IVF) treatment. The remaining 82 couples proceeded with PGT. Fertility assessment prior to IVF treatment showed a higher percentage of male infertility in males affected with NF1 compared to the partners of affected females. Cardiac evaluations in women with NF1 showed no contraindications for IVF treatment or pregnancy. For 67 couples, 143 PGT cycles were performed. Complications of IVF treatment were not more prevalent in affected females compared to partners of affected males. The transfer of 174 (out of 295) unaffected embryos led to 42 ongoing pregnancies with a pregnancy rate of 24.1% per embryo transfer. There are no documented cases of misdiagnosis following PGT in this cohort. With these results, we aim to provide an overview of PGT for NF1 with regard to success rate and safety, to optimize reproductive counseling and PGT treatment for NF1 patients.</p