Bidding Behavior and Decision Costs in Field Experiments

Whether rationality of economic behavior increases with expected payoffs and decreases with the cognitive cost it takes to formulate an optimal strategy remains an open question. We explore these issues with field data, using individual bids from sealed-bid auctions in which we sold nearly $10,000 worth of sports cards. Our results incdicate that stakes do indeed matter, as high-priced ($70) cards produced more of the theoretically predicted strategic behavior than did lower-priced ($3) cards. We find additional evidence consistent with the importance of cognitive costs, as subjects more experienced with sports card auctions exhibited a greater tendency to behave strategically than did less experienced bidders.

Líquenes corticícolas en el caribe colombiano

Se documentó la composición de la flora liquénica corticícola de cinco localidades de la región Caribe colombiana, tres de tierras bajas (planicies) y dos de tierras altas (macizos montañosos). Se encontraron 348 morfoespecies de líquenes corticícolas, basadas en 950 ejemplares, de las cuales 215 se determinaron a nivel de especie y 62 a género (debido a la ausencia de estructuras reproductivas o a la carencia de trabajos taxonómicos). El resto de las especies (71) constituyó un grupo líquenes costrosos estériles que carecen de caracteres específicos para su identificación. Se encontraron 115 registros nuevos para Colombia, la mayoría de especies son registros nuevos para las áreas de estudio. El número total de especies para la región Caribe, incluyendo los estudios previos de macrolíquenes y líquenes foliícolas, se estimó en aproximadamente 400

Multi-disciplinary Lessons Learned from Low-Tech Coral Farming and Reef Rehabilitation: II. Coral Demography and Social-Ecological Benefits

Low-tech coral farming and reef rehabilitation have become important tools to foster community-based participation in the management of coastal social-ecological systems. Lessons learned from coral demographic dynamics, ecosystem-level benefits, and sociological dynamics achieved in Culebra Island, Puerto Rico, are discussed. Important gaps regarding social-ecological interactions are also addressed. Coral reef rehabilitation efforts must be adaptive and focused on maximizing resilience as a long-term goal, with emphasis on managing non-linear dynamics, thresholds, environmental and climate uncertainty, and ecological surprises. In this context, coral demographic modelling becomes fundamental to address, not only ecological, but also sociological concerns. Only through sustained support and input of harvested corals restored populations, and by increasing the spatial scale of reef rehabilitation, restored populations can remain viable and grow under present and projected environmental and climate conditions. Understanding sociological dynamics, learning from others experiences, integrating visioning and scenario building, leadership building, multi-sectorial agents and actor groups, and strengthening cross-sectorial social networking are necessary adaptive approaches to cope with future environmental and climate changes, and are an integral part of reef rehabilitation. The combined benefits to social-ecological systems are multiple. With proper planning, design, funding, local support, and implementation, these can have long-lasting impacts in restoring coastal resilience

Are Subjects Making Financial Decisions in Lab Auctions or Are They Just Gambling?

Optimal bidding strategies in first-price and Dutch auctions are theoretically isomorphic but depend on bidder risk attitudes. However, laboratory experiments consistently find different behaviour between auction formats. This article explores whether the notion in psychology that financial and gambling risks are viewed differently can explain the discrepancy. Ultimately, the evidence does not support this hypothesis, but a bidder\u27s propensity to gamble is associated with how much risk he takes in both auctions whereas his propensity to take financial risks is not. The results suggest that subjects may view themselves as gambling in laboratory auctions rather than making financial decisions

Role of shear stress and tPA concentration in the fibrinolytic potential of thrombi

Funding: This research was funded by British Heart Foundation PG/08/127/26517 awarded to N.A.B. and D.E.N. C.S.W. and N.J.M. were supported by the British Heart Foundation project grants (PG/15/82/31721 and PG/20/17/35050). D.E.N. and A.J.L. were supported by the British Heart Foundation project grant PG/04/131/18118. D.E.N. is supported by the British Heart Foundation (CH/09/002, RE/18/5/34216, RG/16/10/32375) and is the recipient of a Wellcome Trust Senior Investigator Award (WT103782AIA).Peer reviewedPublisher PD

Efficient Design and Analysis of Lightweight Reinforced Core Sandwich and PRSEUS Structures

Design, analysis, and sizing methods for two novel structural panel concepts have been developed and incorporated into the HyperSizer Structural Sizing Software. Reinforced Core Sandwich (RCS) panels consist of a foam core with reinforcing composite webs connecting composite facesheets. Boeing s Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) panels use a pultruded unidirectional composite rod to provide axial stiffness along with integrated transverse frames and stitching. Both of these structural concepts are ovencured and have shown great promise applications in lightweight structures, but have suffered from the lack of efficient sizing capabilities similar to those that exist for honeycomb sandwich, foam sandwich, hat stiffened, and other, more traditional concepts. Now, with accurate design methods for RCS and PRSEUS panels available in HyperSizer, these concepts can be traded and used in designs as is done with the more traditional structural concepts. The methods developed to enable sizing of RCS and PRSEUS are outlined, as are results showing the validity and utility of the methods. Applications include several large NASA heavy lift launch vehicle structures

Angiography-derived index of microcirculatory resistance as a novel, pressure-wire-free tool to assess coronary microcirculation in ST elevation myocardial infarction

Immediate assessment of coronary microcirculation during treatment of ST elevation myocardial infarction (STEMI) may facilitate patient stratification for targeted treatment algorithms. Use of pressure-wire to measure the index of microcirculatory resistance (IMR) is possible but has inevitable practical restrictions. We aimed to develop and validate angiography-derived index of microcirculatory resistance (IMRangio) as a novel and pressure-wire-free index to facilitate assessment of the coronary microcirculation. 45 STEMI patients treated with primary percutaneous coronary intervention (pPCI) were enrolled. Immediately before stenting and at completion of pPCI, IMR was measured within the infarct related artery (IRA). At the same time points, 2 angiographic views were acquired during hyperaemia to measure quantitative flow ratio (QFR) from which IMRangio was derived. In a subset of 15 patients both IMR and IMRangio were also measured in the non-IRA. Patients underwent cardiovascular magnetic resonance imaging (CMR) at 48 h for assessment of microvascular obstruction (MVO). IMRangio and IMR were significantly correlated (rho: 0.85, p < 0.001). Both IMR and IMRangio were higher in the IRA rather than in the non-IRA (p = 0.01 and p = 0.006, respectively) and were higher in patients with evidence of clinically significant MVO (> 1.55% of left ventricular mass) (p = 0.03 and p = 0.005, respectively). Post-pPCI IMRangio presented and area under the curve (AUC) of 0.96 (CI95% 0.92-1.00, p < 0.001) for prediction of post-pPCI IMR > 40U and of 0.81 (CI95% 0.65-0.97, p < 0.001) for MVO > 1.55%. IMRangio is a promising tool for the assessment of coronary microcirculation. Assessment of IMR without the use of a pressure-wire may enable more rapid, convenient and cost-effective assessment of coronary microvascular function

Hyper-acute cardiovascular magnetic resonance T1 mapping predicts infarct characteristics in patients with ST elevation myocardial infarction

Background Myocardial recovery after primary percutaneous coronary intervention in acute myocardial infarction is variable and the extent and severity of injury are difficult to predict. We sought to investigate the role of cardiovascular magnetic resonance T1 mapping in the determination of myocardial injury very early after treatment of ST-segment elevation myocardial infarction (STEMI). Methods STEMI patients underwent 3 T cardiovascular magnetic resonance (CMR), within 3 h of primary percutaneous intervention (PPCI). T1 mapping determined the extent (area-at-risk as %left ventricle, AAR) and severity (average T1 values of AAR) of acute myocardial injury, and related these to late gadolinium enhancement (LGE), and microvascular obstruction (MVO). The characteristics of myocardial injury within 3 h was compared with changes at 24-h to predict final infarct size. Results Forty patients were included in this study. Patients with average T1 values of AAR ≥1400 ms within 3 h of PPCI had larger LGE at 24-h (33% ±14 vs. 18% ±10, P = 0.003) and at 6-months (27% ±9 vs. 12% ±9; P  9.5%) with 100% positive predictive value at the optimal cut-off of 1400 ms (area-under-the-curve, AUC 0.88, P = 0.006). Conclusion Hyper-acute T1 values of the AAR (within 3 h post PPCI, but not 24 h) predict a larger extent of MVO and infarct size at both 24 h and 6 months follow-up. Delayed CMR scanning for 24 h could not substitute the significant value of hyper-acute average T1 in determining infarct characteristics