Multiple Items, Ascending Price Auctions: An Experimental Examination of Alternative Auction Sequences

The paper investigates the revenue and efficiency of different ascending price auction architectures for the sale of three items and five bidders. Four architectures are studied: two different sequences of single item auctions, simultaneous auctions with a common countdown clock, and simultaneous auctions with item specific countdown clocks. A countdown clock measures the time until the auction closes but resets with each new bid. The environment contains independent private values, no uncertainty about own preferences, no information about other’s preferences, and a one unit budget constraint. The Nash equilibrium best response with straight forward bidding fits both dynamic and outcome data well. When non-unique Nash equilibria exist as in the case of simultaneous markets with a common clock, the social value maximizing Nash equilibrium emerges as the equilibrium selection. Both total revenue and efficiencies depend on the architecture as predicted by the Nash model, with the exception of the independent clocks architecture, which performs poorly on all dimensions

Does acellular dermal matrix expand in response to tissue expander inflation?

Background Acellular dermal matrices (ADMs) have recently become widely used in breast reconstruction, but the correlation between the final expander volume and the surface area of the ADM is not well understood. In this study, the expansion of the surface area of ADM and the expander volume was studied retrospectively in cases of acellular dermis–assisted tissue expander breast reconstruction. Methods Twenty cases of immediate breast reconstruction using an ADM–assisted tissue expander from January 2015 to December 2015 were evaluated. In all 20 cases, CGCryoDerm was used as the matrix, with a thickness of 1–3 mm. No slit incisions were made. Finally, the proportional increase in the area of the fully expanded ADM was compared to that of the tissue expander volume. Results The proportional increase in the ADM surface area was calculated to be from 1.1 to 2.46, with a mean value of 1.7. Additionally, under the assumption that the expander had a spherical shape, the increase in its radius (the cube root of its volume) was assessed. The range of the proportional increase in the expander radius was 1.1 to 2.24, with a mean value of 1.66. The proportional increase in the radius of the expanded ADM surface area ranged from 1.04 to 1.34, with a mean ratio of 1.28. Conclusions The results of this study confirmed that the ADM expanded when the tissue expander was inflated. However, the ADM expanded to a lesser extent than the tissue expander, indicating that the muscle and other tissues expanded more than the ADM when the tissue expander was inflated

Electrochemical Properties of Polyaniline-Coated Li-Rich Nickel Manganese Oxide and Role of Polyaniline Coating Layer

Polyaniline is coated on Li[Li 0.2 Ni 0.2 Mn 0.6 ]O 2 synthesized via co-precipitation. X-ray diffraction patterns exhibit that the polyaniline coating does not affect structural change of the Li[Li 0.2 Ni 0.2 Mn 0.6 ]O 2 , and the resulting transmission electron microscopic images show the presence of coating layers on the surface of Li[Li 0.2 Ni 0.2 Mn 0.6 ]O 2 . Electrochemical tests using coin type cells confirm that the surface modification by polyaniline is effective in maintaining capacity and retention upon cycling. The conducting coating character also assists improvement in rate capability. The polyaniline layer forms F-doped polyaniline during cycling, as is proved by time-of-flight secondary ion mass spectroscopy. Therefore, the presence of the polyaniline layers plays a role in lowering HF levels via scavenging F − from HF in the electrolyte, and this F-doped polyaniline layer also assists in protecting the Li [Li 0.2 Efforts have been made to improve their intrinsic low rate capability stemming from the tetravalent Mn in the oxide matrix and cyclability as well. Hence, partial substitutions of Mn site with other elements or surface modifications have been made. 10,12 A recent report by Kang et al. 14 suggested that surface modification by Al(OH) 3 on Li[Li 0.2 Ni 0.2 Mn 0.6 ]O 2 was fairly effective in capacity retention, rate capability, and thermal stability. Similar effects were also reported using Al 2 O 3 coating and AlPO 4 coating on the over-lithiated manganese oxides. 17,18 Furthermore, we perceive the main problem of oxide coating to be difficulty in complete encapsulation of active materials like core-shell materials due to condensation and crystal growth of the coating materials even at mild heat-treatment condition; it, hence, shows an islands-like coating. 18 For the reason, we object to complete encapsulation of Li[Li 0.2 Ni 0.2 Mn 0.6 ]O 2 using a conductive polyaniline, which does not need further heat-treatment after polymerization. Also, the conductive coating layers are expected to improve the rate capability of the active material. In this paper, we introduce the details of polyaniline-coated Li [ • C for 5 h. The dehydrates were thoroughly mixed with an appropriate amount of LiOH (samchun) and calcined at 900 • C for 15 h in air. In attempt to modify the as-synthesized active materials with polyaniline (hereafter referred as to be PANi), Cl − -doped emeraldine salt state PANi ([C 24 H 26 N 4 (Cl) 2 ] n ) was polymerized with aniline monomer (C 6 H 5 NH 2 ) and ammonium persulfate ((NH 4 ) 2 S 2 O 8 ,). First, aniline monomer and ammonium persulfate were separately poured into 1M HCl aqueous solution, and they were mixed to self-polymerize for 2 days. And the produced PANi in the solution was rinsed with absolute ethanol and acetone to remove the residual monomer, oligomer, and low molecular weight organic intermediates. To prepare violet pernigraniline base state (hereafter referred as to be VPB) PANi which needs to be dissolved in N-methyl-2-pyrrolinon(NMP) or m-cresol and so on, 19,20 the Cl − -doped PANi was poured into a 1M NaOH aqueous solution and continuously stirred at 350 rpm for 2 days. Then, the solution was dried at 80 • C in air. The obtained VPB powders were mixed with campor-10-sulfonic acid, β (CSA, Sigma-aldrich, with a ratio of 4:1 in weight) to prepare (SO) 3 2− -doped emeraldine salt state (hereafter referred as to be ES) PANi and dissolved into N-methyl-2-pyrrolinon (NMP X-ray diffractometry (XRD, Rint-2000, Rigaku) and highresolution transmission electron microscopy (HR-TEM, JEM-3010, JEOL) were employed to characterize the synthesized powders. Timeof-flight secondary ion mass spectroscopy (ToF-SIMS, PHI TRIFT V nanoTOF, ULVAC-PHI) was also used to confirm the presence of th

Cordycepin inhibits human ovarian cancer by inducing autophagy and apoptosis through Dickkopf-related protein 1/β-catenin signaling

Cordycepin, the major active component from Cordyceps militaris, has been reported to significantly inhibit some types of cancer; however, its effects on ovarian cancer are still not well understood. In this study, we treated human ovarian cancer cells with different doses of cordycepin and found that it dose-dependently reduced ovarian cancer cell viability, based on Cell counting kit-8 reagent. Immunoblotting showed that cordycepin increased Dickkopf-related protein 1 (Dkk1) levels and inhibited β-catenin signaling. Atg7 knockdown in ovarian cancer cells significantly inhibited cordycepin-induced apoptosis, whereas β-catenin overexpression abolished the effects of cordycepin on cell death and proliferation. Furthermore, we found that Dkk1 overexpression by transfection downregulated the expression of c-Myc and cyclin D1. siRNA-mediated Dkk1 silencing downregulated the expression of Atg8, beclin, and LC3 and promoted β-catenin translocation from the cytoplasm into the nucleus. These results suggest that cordycepin inhibits ovarian cancer cell growth, possibly through coordinated autophagy and Dkk1/β-catenin signaling. Taken together, our findings provide new insights into the treatment of ovarian cancer using cordycepin

Transmembrane and Ubiquitin-Like Domain-Containing Protein 1 (Tmub1/HOPS) Facilitates Surface Expression of GluR2-Containing AMPA Receptors

Some ubiquitin-like (UBL) domain-containing proteins are known to play roles in receptor trafficking. Alpha-amino-3- hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs) undergo constitutive cycling between the intracellular compartment and the cell surface in the central nervous system. However, the function of UBL domain-containing proteins in the recycling of the AMPARs to the synaptic surface has not yet been reported. Here, we report that the Transmembrane and ubiquitin-like domain-containing 1 (Tmub1) protein, formerly known as the Hepatocyte Odd Protein Shuttling (HOPS) protein, which is abundantly expressed in the brain and which exists in a synaptosomal membrane fraction, facilitates the recycling of the AMPAR subunit GluR2 to the cell surface. Neurons transfected with Tmub1/HOPSRNAi plasmids showed a significant reduction in the AMPAR current as compared to their control neurons. Consistently, the synaptic surface expression of GluR2, but not of GluR1, was significantly decreased in the neurons transfected with the Tmub1/HOPS-RNAi and increased in the neurons overexpressing EGFP-Tmub1/HOPS. The altered surface expression of GluR2 was speculated to be due to the altered surface-recycling of the internalized GluR2 in our recycling assay. Eventually, we found that GluR2 and glutamate receptor interacting protein (GRIP) were coimmunoprecipitated by the anti-Tmub1/ HOPS antibody from the mouse brain. Taken together, these observations show that the Tmub1/HOPS plays a role in regulating basal synaptic transmission; it contributes to maintain the synaptic surface number of the GluR2-containing AMPARs by facilitating the recycling of GluR2 to the plasma membrane