Bayesian Incentive Compatibility via Fractional Assignments

Very recently, Hartline and Lucier studied single-parameter mechanism design problems in the Bayesian setting. They proposed a black-box reduction that converted Bayesian approximation algorithms into Bayesian-Incentive-Compatible (BIC) mechanisms while preserving social welfare. It remains a major open question if one can find similar reduction in the more important multi-parameter setting. In this paper, we give positive answer to this question when the prior distribution has finite and small support. We propose a black-box reduction for designing BIC multi-parameter mechanisms. The reduction converts any algorithm into an eps-BIC mechanism with only marginal loss in social welfare. As a result, for combinatorial auctions with sub-additive agents we get an eps-BIC mechanism that achieves constant approximation.Comment: 22 pages, 1 figur

Separating the Kinetic and Sorption Parameters of Mixed Chlorinated Solvents in Contact with Granular Iron

Chlorinated solvents and nitroaromatic solvents in drinking-water supplies are an important concern for public health. Granular iron, the most common medium in permeable reactive barriers (PRBs), is very effective at removing organic chemicals, such as chlorinated solvents and nitroaromatic compounds, from groundwater. In an effort to improve barrier designs, studies have been undertaken to examine the iron surface, as well as the reaction kinetics of granular iron. The development of the kinetic iron model (KIM) in 2009, which was derived specifically for PRB settings, made it possible for the first time to assess the simultaneous contributions of sorption and reaction to contaminant degradation rates in iron PRBs, providing a new tool to improve PRB design. This work extended the previous studies that used the KIM by applying the kinetic model to study the effects of iron aging on the reaction kinetics of chlorinated solvents and nitroaromatic solvents. It was found that over time and exposure to water and oxidizing organics, iron tended to lose sorption sites associated with the highest reactivities , but gained reactive sorption capacity to sites with lower reactivity. In the short term, the increasing sorption capacity led to overall faster reaction rates than were observed with new iron. The results also indicated that the KIM parameters were more than simple fitting parameters. As expected, the nitroaromatic compounds tested (4ClNB and 4AcNB) reacted faster than the chlorinated solvents tested (PCE and TCE). Analysis of the data with the KIM indicated the rate differences were due to the surface reaction rate constant, not sorption. This result matched expectations based on earlier studies of these classes of organic chemicals. To test the accuracy of the estimated kinetic and sorption parameters, determined with novel methods in this work, a one dimensional transport model with Langmuir sorption and KIM kinetics was developed to generate synthetic data sets. The model was prepared with the ability to assess intra- and interspecies competition between TCE and PCE in the column experiments. Synthetic data were analyzed with the methods used to interpret the laboratory data and accurate estimates of the input parameters were calculated, validating the methodology. Finally, the activation energy of the 4-chloronitrobenzene reacting with two types of granular iron, Connelly iron and QMP, in batch reactors was obtained to assess the role of mass transfer in controlling the kinetics. Previous work had indicated that mass transfer was not rate controlling with Connelly iron, but QMP was a texturally different form of granular iron that needed further testing. QMP exhibited slower reaction rates compare to Connelly iron. Based on the estimated activation energies (Ea) of the reduction reactions, the reaction mechanism(s) for 4ClNB transformation on Connelly iron and QMP iron were both electron transfer controlled, and the result also suggest that the different transformation rates were therefore related to phases on the solid surface

Finite Temperature Phase Diagram in Rotating Bosonic Optical Lattice

Finite temperature phase boundary between superfluid phase and normal state is analytically derived by studying the stability of normal state in rotating bosonic optical lattice. We also prove that the oscillation behavior of critical hopping matrix directly follows the upper boundary of Hofstadter butterfly as the function of effective magnetic field.Comment: 10 pages, 2 figure

tourrGui: A gWidgets GUI for the Tour to Explore High-Dimensional Data Using Low-Dimensional Projections

This paper describes a graphical user interface (GUI) for the tourr package in R. The tour is a dynamic graphical method for viewing multivariate data. The GUI allows users to interact with a tour in order to explore the data for structures like clustering, outliers, nonlinear dependence. Users can pause the tour, choose a subset of variables, color points by other variables, and switch between several different types of tours

The role of IL-6/JAK2/STAT3 signaling pathway in cancers

Interleukin-6 (IL-6) is a pleiotropic cytokine involved in immune regulation. It can activate janus kinase 2 (JAK2)-signal transducer and activator of transcription 3 (STAT3) signaling pathway. As one of the important signal transduction pathways in cells, JAK2/STAT3 signaling pathway plays a critical role in cell proliferation and differentiation by affecting the activation state of downstream effector molecules. The activation of JAK2/STAT3 signaling pathway is involved in tumorigenesis and development. It contributes to the formation of tumor inflammatory microenvironment and is closely related to the occurrence and development of many human tumors. This article focuses on the relationship between IL-6/JAK2/STAT3 signaling pathway and liver cancer, breast cancer, colorectal cancer, gastric cancer, lung cancer, pancreatic cancer and ovarian cancer, hoping to provide references for the research of cancer treatment targeting key molecules in IL-6/JAK2/STAT3 signaling pathway

A continuing 30-year decline in water quality of Jiaojiang Estuary, China

AbstractA quantitative description of a long-term series of aquatic environmental factors and their spatial distributions was generated using measured data from the Jiaojiang Estuary from 1982 to 2011. The aquatic environmental factors included suspended matter, salinity, and nutrients. Based on these factors, the aquatic ecosystem health in the Jiaojiang Estuary over the last 30 years was analyzed. The results indicated that the suspended matter concentration in the estuary was mainly affected by the amounts of suspended sediment and solid waste, with the value fluctuating over a long period, and the range of high concentration expanded continually; the salinity was mainly affected by precipitation and surface water resources, showing an overall decreasing trend, and the region with low salinity moved seaward and toward the reclamation areas; and the nutritional status, mainly affected by discharge of industrial wastewater and domestic sewage, was satisfactory in the 1980s and 1990s, but the status became severe in recent years. Reclamation had a great influence on these three factors: high reclamation strength led to a significant increase in the suspended matter concentration and a deterioration of the nutritional status, and the reclamation rate was negatively related with the salinity in the estuary. There was a significant positive correlation between the health status of the aquatic ecosystem and salinity, with a correlation coefficient of 0.93. The correlation coefficient between the health status and nutritional status was −0.71, while the correlation between the suspended matter concentration and health status was not as significant as that of the other two factors. The dynamics of the aquatic environment could be divided into four stages: sustainable health from the 1980s to the 1990s, continued deterioration from 2000 to 2003, improvement from 2004 to 2005, and secondary deterioration from 2006 to 2011. The Jiaojiang Estuary is faced with imminent environmental pressure at present