Privacy and Truthful Equilibrium Selection for Aggregative Games

We study a very general class of games --- multi-dimensional aggregative games --- which in particular generalize both anonymous games and weighted congestion games. For any such game that is also large, we solve the equilibrium selection problem in a strong sense. In particular, we give an efficient weak mediator: a mechanism which has only the power to listen to reported types and provide non-binding suggested actions, such that (a) it is an asymptotic Nash equilibrium for every player to truthfully report their type to the mediator, and then follow its suggested action; and (b) that when players do so, they end up coordinating on a particular asymptotic pure strategy Nash equilibrium of the induced complete information game. In fact, truthful reporting is an ex-post Nash equilibrium of the mediated game, so our solution applies even in settings of incomplete information, and even when player types are arbitrary or worst-case (i.e. not drawn from a common prior). We achieve this by giving an efficient differentially private algorithm for computing a Nash equilibrium in such games. The rates of convergence to equilibrium in all of our results are inverse polynomial in the number of players $n$. We also apply our main results to a multi-dimensional market game. Our results can be viewed as giving, for a rich class of games, a more robust version of the Revelation Principle, in that we work with weaker informational assumptions (no common prior), yet provide a stronger solution concept (ex-post Nash versus Bayes Nash equilibrium). In comparison to previous work, our main conceptual contribution is showing that weak mediators are a game theoretic object that exist in a wide variety of games -- previously, they were only known to exist in traffic routing games

Identification and Localization of Proteins Associated with Biomineralization in the Iron Deposition Vesicles of Honeybees (Apis mellifera)

Honeybees (Apis mellifera) form superparamagnetic magnetite to act as a magnetoreceptor for magnetoreception. Biomineralization of superparamagnetic magnetite occurs in the iron deposition vesicles of trophocytes. Even though magnetite has been demonstrated, the mechanism of magnetite biomineralization is unknown. In this study, proteins in the iron granules and iron deposition vesicles of trophocytes were purified and identified by mass spectrometry. Antibodies against such proteins were produced. The major proteins include actin, myosin, ferritin 2, and ATP synthase. Immunolabeling and co-immunoprecipitation studies suggest that iron is stored in ferritin 2 for the purpose of forming 7.5-nm diameter iron particles and that actin-myosin-ferritin 2 may serve as a transporter system. This system, along with calcium and ATP, conveys the iron particles (ferritin) to the center of iron deposition vesicles for iron granules formation. These proteins and reactants are included in iron deposition vesicles during the formation of iron deposition vesicles from the fusion of smooth endoplasmic reticulum. A hypothetical model for magnetite biomineralization in iron deposition vesicles is proposed for honeybees

Multiviewing Ultrasonic Transducer System for Flaw Reconstruction

The characterization of failure-initiating flaws in materials and components is an important task in the assurance of structural integrity. Based on ultrasonic signals scattered from the flaw in a number of directions, inverse scattering algorithms may be used to reconstruct the size, shape and orientation of the flaw. One of the more successful methods for elastic wave inverse scattering and flaw sizing has been the inverse Born algorithm in the long and intermediate wavelength regime

Acoustic Emissions at an Open Crack

Both finite difference and finite element techniques have been shown to be capable of modeling the propagation of acoustic emissions (AE) [1,2]. However, those calculations could also be done using the simpler Green’s function methods [3]. In this work the finite element method is used to model a problem that includes complexities that cannot be handled using the Green’s function methods

Comparing the Effect of Concept Mapping and Conventional Methods on Nursing Students' Practical Skill Score

Background: Development of practical skills in the field of nursing education has remained a serious and considerable challenge in nursing education. Moreover, newly graduated nurses may have weak practical skills, which can be a threat to patients’ safety. Objectives: The present study was conducted to compare the effect of concept mapping and conventional methods on nursing students’ practical skills. Patients and Methods: This quasi-experimental study was conducted on 70 nursing students randomly assigned into two groups of 35 people. The intervention group was taught through concept mapping method, while the control group was taught using conventional method. A two-part instrument was used including a demographic information form and a checklist for direct observation of procedural skills. Descriptive statistics, chi-square, independent samples t-tests and paired t-test were used to analyze data. Results: Before education, no significant differences were observed between the two groups in the three skills of cleaning (P = 0.251), injection (P = 0.185) and sterilizing (P = 0.568). The students mean scores were significantly increased after the education and the difference between pre and post intervention of students mean scores were significant in the both groups (P < 0.001). However, after education, in all three skills the mean scores of the intervention group were significantly higher than the control group (P < 0.001). Conclusions: Concept mapping was superior to conventional skill teaching methods. It is suggested to use concept mapping in teaching practical courses such as fundamentals of nursing

Superficial simplicity of the 2010 El Mayor–Cucapah earthquake of Baja California in Mexico

The geometry of faults is usually thought to be more complicated at the surface than at depth and to control the initiation, propagation and arrest of seismic ruptures. The fault system that runs from southern California into Mexico is a simple strike-slip boundary: the west side of California and Mexico moves northwards with respect to the east. However, the M_w 7.2 2010 El Mayor–Cucapah earthquake on this fault system produced a pattern of seismic waves that indicates a far more complex source than slip on a planar strike-slip fault. Here we use geodetic, remote-sensing and seismological data to reconstruct the fault geometry and history of slip during this earthquake. We find that the earthquake produced a straight 120-km-long fault trace that cut through the Cucapah mountain range and across the Colorado River delta. However, at depth, the fault is made up of two different segments connected by a small extensional fault. Both segments strike N130° E, but dip in opposite directions. The earthquake was initiated on the connecting extensional fault and 15 s later ruptured the two main segments with dominantly strike-slip motion. We show that complexities in the fault geometry at depth explain well the complex pattern of radiated seismic waves. We conclude that the location and detailed characteristics of the earthquake could not have been anticipated on the basis of observations of surface geology alone

Observation of superconductivity at 30 K~46 K in AxFe2Se2 (A = Li, Na, Ba, Sr, Ca, Yb, and Eu)

New iron selenide superconductors by intercalating smaller-sized alkali metals (Li, Na) and alkaline earths using high-temperature routes have been pursued ever since the discovery of superconductivity at about 30 K in KFe2Se2, but all have failed so far. Here we demonstrate that a series of superconductors with enhanced Tc=30~46 K can be obtained by intercalating metals, Li, Na, Ba, Sr, Ca, Yb, and Eu in between FeSe layers by the ammonothermal method at room temperature. Analysis on their powder X-ray diffraction patterns reveals that all the main phases can be indexed based on body-centered tetragonal lattices with a~3.755-3.831 {\AA} while c~15.99-20.54 {\AA}. Resistivities show the corresponding sharp transitions at 45 K and 39 K for NaFe2Se2 and Ba0.8Fe2Se2, respectively, confirming their bulk superconductivity. These findings provide a new starting point for studying the properties of these superconductors and an effective synthetic route for the exploration of new superconductors as well.Comment: 22 pages, 5 figure

Structural Modification in Carbon Nanotubes by Boron Incorporation

We have synthesized boron-incorporated carbon nanotubes (CNTs) by decomposition of ferrocene and xylene in a thermal chemical vapor deposition set up using boric acid as the boron source. Scanning and transmission electron microscopy studies of the synthesized CNT samples showed that there was deterioration in crystallinity and improvement in alignment of the CNTs as the boron content in precursor solution increased from 0% to 15%. Raman analysis of these samples showed a shift of ~7 cm−1in wave number to higher side and broadening of the G band with increasing boron concentration along with an increase in intensity of the G band. Furthermore, there was an increase in the intensity of the D band along with a decrease in its wave number position with increase in boron content. We speculate that these structural modifications in the morphology and microstructure of CNTs might be due to the charge transfer from boron to the graphite matrix, resulting in shortening of the carbon–carbon bonds