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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jet.2009.08.001 Byline: Maxim Ivanov Keywords: Communication; Information; Cheap talk; Mediation Abstract: This paper investigates communication between an informed expert and an uninformed principal via a strategic mediator. We demonstrate that, for any bias in the parties' preferences, there exists a strategic mediator that provides the highest expected payoff to the principal, as if the players had communicated through an optimal non-strategic mediator. Author Affiliation: Department of Economics, McMaster University, 1280 Main Street Hamilton, ON, Canada L8S 4M4 Article History: Received 3 December 2008; Revised 9 August 2009; Accepted 16 August 2009 Article Note: (footnote) [star] I am grateful to Andreas Blume, Kalyan Chatterjee, Navin Kartik, Vijay Krishna, Hao Li, Timofiy Mylovanov, Gregory Pavlov, and seminar participants at the University of Toronto for helpful comments. I also owe special thanks to two anonymous referees and the editor for their suggestions. Misty Ann Stone provided invaluable help with copy editing the manuscript. All mistakes are my own. The paper has been previously circulated under the title 'Communication via a Biased Mediator'.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jet.2009.11.002 Byline: Maxim Ivanov Keywords: Communication; Information; Cheap talk Abstract: This paper focuses on issues of allocating authority between an uninformed principal and an informed expert. We analyze the benefits of informational control -- restricting the precision of the expert's information (without learning its content). In this case, the result of Dessein (2002) that delegating decisions to a perfectly informed expert is better than communication when preferences between the expert and the principal are not too far apart is reversed. We demonstrate that these organizational forms -- informational control and delegation -- can be either complements or substitutes, depending on the principal's ability to affect the expert's discretion about the set of allowed policies. Author Affiliation: Department of Economics, McMaster University, 1280 Main Street Hamilton, ON, Canada L8S 4M4 Article History: Received 7 September 2008; Revised 20 September 2009; Accepted 21 September 2009

• Nanosensors exhibit noise immunity and greater sensitivity to the signal. • The hardware and software complex records spontaneous activity of myocardial cells in real time. • Real-time ECG recording in the frequency range from 0 to 10,000 Hz. • Recording of micropotentials of more than 1 μV without filtering and averaging. • The activity of cardiomyocytes decreases significantly 1 day before the lethal outcome. Cardiovascular diseases are one of the leading causes of premature death worldwide. Sudden cardiac death is most often caused by previously undetected coronary heart disease. Therefore, it is necessary to create new high-resolution diagnostic equipment for non-invasive dynamic monitoring of spontaneous activity of myocardial cells in population screening. Nanosensors with greater sensitivity and noise immunity compared to existing electrodes were developed for ECG recording. A nanosensor-based hardware and software complex and special programs to ensure non-invasive recording and processing of micropotentials of the heart were created. Preliminary medical studies in volunteers showed the possibility of assessing a spontaneous activity of myocardial cells in dynamic observations. [ABSTRACT FROM AUTHOR]

Bioplastics have emerged to minimize the ecological footprint of non-degradable plastics. However, the effect of their degradation in aquatic systems, including the interaction with toxic metals, is still unexplored. In this work, the influence of UV-aging on structure, chemistry, wettability, rigidity, and Hg-sorption of commercially available bioplastic (BIO)- and polyethylene (PE)-based films was studied. To mimetize the materials disposal in fresh-/saltwaters, non-saline/saline aqueous solutions were used in Hg-sorption studies. ATR-FTIR spectra revealed that the BIO film was a coblended starch/polyester-based material, whose microstructure, physicochemical, and mechanical properties changed after UV-aging to a higher extent than in PE film. AFM and kinetic modelling pointed out electrostatic interactions/complexation as the mechanisms involved in the increased Hg-sorption by the UV-aged BIO film. An increased salinity did not impair its Hg-sorption. Therefore, when disposed in aquatic systems, starch/polyester-based bioplastics can play a potential vector for amplifying Hg along the food chain. [Display omitted] • BIO film revealed to be a coblended starch/polyester-based material. • BIO film had higher Hg-sorption ability than the PE film. • UV-aging highly increased the BIO film Hg sorption capacity. • Hg was caught by the BIO film through electrostatic/complexation mechanisms. • Starch/polyester-based films may amplify the Hg in aquatic environments. [ABSTRACT FROM AUTHOR]

There are pronounced interindividual variations in drug metabolism, drug responses, and the incidence of adverse drug reactions. To a certain extent such variability can be explained by genetic factors, but epigenetic modifications, which are relatively scarcely described so far, also contribute. It is known that a novel class of drugs termed epidrugs intervene in the epigenetic control of gene expression, and many of these are now in clinical trials for disease treatment. In addition, disease prognosis and drug treatment success can be monitored using epigenetic biomarkers. Here we review these novel aspects in pharmacology and address intriguing future opportunities for gene-specific epigenetic editing. [ABSTRACT FROM AUTHOR]

The distribution and enrichment of trace metals in sediments of the South China Sea along the entire coast of Vietnam were described. The concentrations of Cr, Ni, Zn, and Pb in the sediments showed a significant positive correlation with fine-sized fractions and TOC. In contrast, the concentration of As was not positively correlated with particle size and other metals. The relatively positive correlations of Cd with Fe, Al, Ti, Sc, TOC, P, Cr, Ni, Zn, and Pb indicated that it comes from different sources. Ecotoxicological indexes of all elements showed low values, except for Cd in the southwestern part of the South China Sea area, which is likely related to the influx of suspended matter from the Mekong River. • Trace metals in sediment from the Vietnam Shelf, South China Sea were assessed. • Ecotoxicological indexes in sediments show low to moderate contamination. • Dominant sources of elements were natural, except Cd. [ABSTRACT FROM AUTHOR]

The specific activities of natural (210Pb, 226Ra, and 232Th) and artificial (137Cs, 239,240Pu, and 241Am) radionuclides in the sediments of two North Caucasus lakes were determined. The two lakes, Lake Khuko and Lake Donguz-Orun, differ in their sedimentation conditions. Based on the use of unsupported 210Pb ex and both Chernobyl-derived and bomb-derived 137Cs as chronological markers, it was established that the sedimentation rates in Lake Khuko over the past 55–60 y did not exceed 0.017 cm y−1. Sedimentation rates in Lake Donguz-Orun were found to be more than an order of magnitude higher. In the latter case, the sedimentation rates for the period from 1986 to the present were over 1.5 times higher than they were for the period 1963–1986. The differences in sedimentation rates were due to differences in the rates of denudation of their respective catchment areas. The specific activities of artificial radionuclides (137Cs, 2600 Bq kg−1; 239,240Pu, 162 Bq kg−1; and 241Am, 36 Bq kg−1) and their ratios in the sediments of Lake Khuko show that their deposition was mainly due to global stratospheric fallout of technogenic radionuclides associated with nuclear bomb testing during 1954–1963—rather than fallout from the Chernobyl accident. Several factors, including the mode of precipitation, features of the surface runoff, and location of Lake Khuko, were responsible for the accumulation of artificial radionuclides. Image 1 • Both 137Cs and 210Pb ex were used for evaluation of sedimentation rates in the two Caucasus lakes. • Sedimentation rate in Donguz-Orun lake located in proglacial zone increase in 1,5 times since 1986. • Global warming is the main reason of increasing denudation rates in periglacial zone. • High concentrations of technogenic radionuclides were determined in sediments of Lake Khuko. • The possible contribution of different sources of Khuko lake sediment contamination is determined. Main finding: It was determined that global warming is the primary reason the denudation rates in the periglacial zone are increasing. The possible sources of the radioactive contamination of the Khuko lake sediment were also determined. [ABSTRACT FROM AUTHOR]

The molecular structure and supramolecular self-assembly, involving intermolecular C H⋯S hydrogen bonds and C H⋯Pt anagostic interactions, as well as the thermal behaviour of two new di- iso -propyl and di- iso -butyl dithiocarbamate platinum(II) complexes was studied using single-crystal XRD, 13C CP-MAS NMR and STA techniques. Two new dialkyldithiocarbamato platinum(II) complexes of [Pt(S 2 CNR) 2 ], R = iso -C 3 H 7 (1) and iso -C 4 H 9 (2), have been prepared and characterised using 13C CP-MAS NMR. The crystal and molecular structures of the isolated compounds were established by single-crystal X-ray diffraction. The unit cell of 1 contains four centrosymmetric discrete molecules of [Pt{S 2 CN(iso -C 3 H 7) 2 } 2 ], of which the pairs are structurally inequivalent to each other (hereafter denoted as molecules 1a and 1b). At the supramolecular level, due to numerous intermolecular C H⋯S hydrogen bonds, the 1a molecules form linear polymeric ribbons, whose interaction with the 1b molecules results in a two-dimensional polymeric network. In the structure of 2 , the construction of supramolecular zigzag chains by non-centrosymmetric molecules of [Pt{S 2 CN(iso -C 4 H 9) 2 } 2 ] is determined by intermolecular C H⋯Pt anagostic interactions. The thermal behaviour of crystalline compounds 1 and 2 was studied by simultaneous thermal analysis (STA), a combination of the TG and DSC techniques, under an argon atmosphere. In both cases, platinum(II) sulfide (PtS) was identified as the main end-product upon thermal decomposition of the complexes at 600 °C. [ABSTRACT FROM AUTHOR]

Here we present a novel solvothermal synthesis approach for the accurate control over the structural features of nickel/reduced graphene oxide (Ni/rGO) nanocomposites for tuneable electrical properties. We discovered that the dynamic chemical structure of GO during reaction, acts as an active template for the controlled nanostructured growth of nickel nanoparticles (Ni NPs). Therefore, the precise control of reaction time offered the possibility to modulate nucleation and coalescence phenomena of Ni NPs, allowing in this way to precisely adjust their size, density and NiO@Ni structure on the final Ni/rGO nanocomposites. The electrophysical properties (work function and conductivity) of different Ni/rGO nanocomposites were determined and found to be directly dependent on the Ni NPs radius and also on the NiO buffer layer width. We confirmed a crucial role of the NiO buffer layer thickness at the Pt-NiO-Ni-NiO-rGO interface changing the conductivity from metallic to those specific to a Schottky contact or to a p-n heterojunction. These new findings reveal a relevant potential for using Ni/rGO nanocomposites as a versatile and promising material for micro-, nano- and optoelectronics as well as for energy storage technologies. Unlabelled Image • GO showed to be an active substrate for the development of Ni/rGO nanocomposites • The size and distribution of Ni NPs were tailored by simple control of the solvothermal reaction time • The NiO@Ni NPs embedded in rGO surface are stable at environmental conditions • The electrophysical properties were dependent on the Ni NPs radius and NiO shell • The conductivity of Ni/rGO changed from metallic to a p-n heterojunction. [ABSTRACT FROM AUTHOR]

Barium titanate (BT) nanoparticles were prepared using both microwave- and conventional oven-assisted hydrothermal syntheses with varying reaction times (1 h, 3 h, and 6 h). In the case of the conventional oven-assisted hydrothermal syntheses, 16 h, 24 h, 48 h and 72 h reaction times were also studied. Structural and morphological evolution of BT particles were investigated. Microwave-assisted hydrothermal synthesis allowed for the rapid formation of nearly pure barium titanate (BT) phase in just 1 h at 200 °C. On the other hand, using a conventional oven as the heat source required at least 6 h of synthesis to achieve a similar material. When the different BT powders were pelletized and sintered at 1300 °C, ceramics with over 95 % density were obtained. The room-temperature (RT) dielectric permittivity exceeded 1750 for BT particles prepared over 6 h using both heating methods. However, a significant distinction emerged when comparing the piezoelectric coefficient (d 33) values. The BT pellet obtained through the sintering of BT synthesized in the conventional oven for 6 h exhibited a notably higher d 33 value, approximately 171 pC/N, as opposed to the 146 pC/N value observed in BT ceramics resulting from the microwave synthesized powders. Among the ceramic BT variations, the one derived from the best-crystallized tetragonal BT particles (CON_72h) displayed the lowest d 33 value at 79 pC/N. These findings underscore the immense potential of microwave- and conventional oven-assisted hydrothermal syntheses in the sustainable production of BT nanomaterials, which can then be sintered to enable the preparation of ceramics with enhanced ferroelectric and piezoelectric properties. [ABSTRACT FROM AUTHOR]

Cr 2+ :ZnS is an important mid-infrared laser material, and Cr 2+ :ZnS nanopowders are very important for the fabrication of transparent ceramics. In this paper, Cr 2+ :ZnS nanopowders were synthesized via a hydrothermal method, in which thioacetamide (TAA) was adopted as sulfur source and reducing agent to avoid the oxidation of Cr 2+ ions. The influences of the hydrothermal time and [Zn 2+ ]/[TAA] ratio on the morphology and particle size of the nanopowders were investigated systematically as well as the reaction mechanism. It is believed that the orientated attachment and Oswald ripening both occurred during the hydrothermal reaction, which resulted in the formation of bimodal particle size distribution. After calcination of the nanopowders under Ar/H 2 atmosphere, the Cr 2+ ions were successfully doped into the Zn 2+ lattice sites, which was supported by the X-ray powder diffraction patterns, the absorption and photoluminescence spectra of the calcination products. The optical properties were similar with those of the samples obtained by thermal diffusion, which means that they have the potential application in the fabrication of Cr 2+ :ZnS transparent ceramics. [ABSTRACT FROM AUTHOR]

A major challenge for integration of functional oxides, such as ferroelectrics, into microelectronics and flexible electronics is the reduction of their processing temperature, which needs to be lower than the degradation temperature of silicon and flexible plastic substrates. Aiming that, attention has been given to low-temperature processing of oxide films by chemical solution deposition (CSD). In the field of ferroelectrics, potassium sodium niobate ((K 1−x Na x)NbO 3 , KNN) has aroused a special interest due to its eco-friendliness, despite the high crystallization temperature. In this work, polycrystalline KNN thin films have been fabricated for the first time at a temperature as low as 400 °C using a modified CSD process, the Seeded Photosensitive Precursor Method (SPPM). Despite this low processing temperature, monophasic and stoichiometric films with appreciable values of remnant polarization, P r ∼ 10.8 μC/cm2, and hysteretic piezoresponse are obtained. These results open a window to the direct integration of KNN films into the high-performance electronic devices. [ABSTRACT FROM AUTHOR]

Transparent magnesium aluminate spinel (MgAl 2 O 4 ) ceramics were fabricated by hot-pressing of the MgO and α-Al 2 O 3 powder mixture using LiF as a sintering aid. Effects of the LiF additive on densification, microstructure and optical properties of MgAl 2 O 4 ceramics were systematically investigated. It has been found that the addition of LiF can effectively remove the porosity and increase the optical transparency of MgAl 2 O 4 ceramics. For the spinel ceramics HP-ed at 1550 °C for 3 h with 1 wt% LiF addition, the average grain size is about 36 µm and the in-line transmittance exceeds 60% at the wavelength of 800 nm. [ABSTRACT FROM AUTHOR]

Diffusion-controlled solid-state reactive sintering is one of the most important steps in fabrication of highly transparent Nd:YAG ceramics using commercial oxide powders as starting materials. The difference in raw powders, especially for the characteristic of Y 2 O 3 powder, will seriously influence the sintering behavior and finally lead to the large difference in microstructure and optical property. Thus, interactions between commercially available α-Al 2 O 3 submicron particles and severely agglomerated Y 2 O 3 nanoparticles during vacuum sintering were investigated in details in the present paper. Upon examining the influence of solid-state reactive diffusion in Nd:YAG ceramics, by optimizing the sintering parameters, highly transparent Nd:YAG ceramics were fabricated by solid-state reactive sintering of Y 2 O 3 , α-Al 2 O 3 and Nd 2 O 3 powders. The in-line transmittances of the ceramics achieved 83.8% and 81% at 1064 nm and 400 nm, respectively. [ABSTRACT FROM AUTHOR]

Highlights: [•] Heat-treatment in oxygen may decrease the internal porosities of Y2O3 powders. [•] Heat-treatment of Y2O3 improved the size matching with Al2O3 after milling. [•] Pretreatment of Y2O3 powders optimized the microstructure of Nd:YAG ceramics. [•] Heat-treatment of Y2O3 powders improved the transparency of Nd:YAG ceramics. [ABSTRACT FROM AUTHOR]

Ho 2 O 3 transparent ceramics were fabricated by vacuum pre-sintering combined with hot isostatic pressing (HIP) post-treatment at relatively low temperature from high-purity Ho 2 O 3 powder calcined at 1000 °C for 4 h. The optimal Ho 2 O 3 ceramic sample prepared by vacuum pre-sintering at 1250 °C and HIP post-treating at 1450 °C has a dense microstructure with average grain size of 0.77 μm, and the in-line transmittances reach 80.7 % at 1550 nm and 76.7 % at 1064 nm. The effect of air annealing on the optical quality of Ho 2 O 3 ceramics was studied, and the existence of compressed pores in the HIP-ed Ho 2 O 3 ceramics was confirmed. The Verdet constants of Ho 2 O 3 ceramics were measured to be -47.4 rad/(T m at 1064 nm and -15.4 rad/(T m at 1561 nm. High transmittance and large Verdet constant in the wavelength regions 1–1.07 μm, 1.3–1.5 μm make Ho 2 O 3 transparent ceramics promising for magneto-optical devices for lasers based on Yb-, Nd-doped materials and telecom lasers. [ABSTRACT FROM AUTHOR]

Neodymium doped yttrium aluminum garnet (Nd:YAG) transparent ceramics were fabricated from Nd:YAG nanopowders synthesized via a reverse precipitation method by vacuum sintering and successive hot isostatic pressing (HIP) post-treatment. The powders obtained by calcining the precursor at 1100 °C for 4 h and then ball milling for 2 h with 0.5 wt% TEOS as sintering aid were used to fabricate Nd:YAG ceramics. The green bodies were vacuum sintered at 1500–1800 °C for 10 h, followed by the HIP at 1600 °C for 3 h in 200 MPa Ar atmosphere. Influence of the calcination temperature on the phase, morphology and particle size evolution of the nanopowders, as well as the optical transparency and microstructure of the obtained Nd:YAG ceramics before and after the HIP post-treatment was investigated in detail. It was found that for the post-treated 1800 °C-vacuum-sintered Nd:YAG ceramic sample, the in-line transmittance increased from 48.0% up to 81.2% at the lasing wavelength of 1064 nm. [ABSTRACT FROM AUTHOR]