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We study the return predictability of a measure of continuing overreaction based on the weighted average of signed volumes. We find that the strategies of buying stocks with upward continuing overreaction and selling stocks with downward continuing overreaction generate significant positive returns and that our measure of continuing overreaction is a better predictor of future returns than past returns. The results are stronger among stocks primarily held by investors more prone to biased self-attribution. Our results provide direct support for the model of return predictability based on overconfidence and biased self-attribution.

Background and Objectives In addition to diagnostic criteria, a broad range of nonspecific clinical features can be found in patients with Kawasaki disease. This lack of specificity may cause confusion with other febrile illnesses and delay the diagnosis of Kawasaki disease. The purpose of this study is to describe common associated symptoms and their clinical significances in children affected with Kawasaki disease. Subjects and Methods As a retrospective study, we reviewed the medical records of 121 children who were treated for Kawasaki disease at Presbyterian medical center from January 2005 to June 2010. All clinical symptoms, laboratory data and echocardiographic findings in patients with KD were collected and analyzed. Results We found that there are 9 associated symptoms, namely cough, rhinorrhea, sputum, abdominal pain, vomiting, diarrhea, arthralgia, headache and seizure, which occur in patients with Kawasaki disease. Among the study group, there were only 32 children with no associated symptoms (26.4%). Patients with abdominal pain and headache had an older mean age than those without such symptoms. The incidence of seizure was significantly higher in incomplete Kawasaki disease patients compared with those with complete Kawasaki disease. Vomiting was highly associated with IVIG non-responder group. Conclusion To decrease the incidence of serious coronary complications due to delayed diagnosis, physicians need to be aware of the manifestations of Kawasaki disease and the possibility of associated symptoms, which, being unspecific, may otherwise not raise any red flags.

We demonstrate the formation of highly ordered hexagonal arrays of hybridized polystyrene-poly(4-vinyl pyridine), PS-PVP, micelles with controllable size by solvent annealing techniques. Because the formation of hybridized micelles was prohibited in the mixture solutions of two different-sized PS-PVP micelles, single-layered films with bimodal self-assemblies of small and large micelles were fabricated from the mixture solutions by adjusting their mixing ratios. When the single-layered films were solvent annealed by saturated vapor of tetrahydrofuran (THF), on the other hand, small and large PS-PVP micelles in the bimodal self-assemblies merged together to form hybridized micelles. In addition, the hybridized micelles arranged themselves in a highly ordered hexagonal array, the diameter and center-to-center distance of which were precisely adjusted by varying the mixing ratio of small to large micelles in the bimodal assemblies.

We have demonstrated micropatterning of a single layer of nanoparticles by combining a self-assembly of diblock copolymer micelles with conventional and soft lithographical methods. On a photoresist micropattern fabricated by conventional photolithography, a single layer of diblock copolymer micelles containing precursors of nanoparticles was spin-coated. By plasma and lift-off processes, nanoparticles with the preservation of a pseudo-hexagonal order of micelles were synthesized in the micropattern without their aggregation. In addition, soft lithography of the microcontact printing technique was combined with the process of diblock copolymer micelles to produce micropatterns of nanoparticles. As an ink of the microcontact printing process, a single-layered film of diblock copolymer micelles was spin-coated directly onto the stamp and then transferred on the substrate by stamping. Formation of a single layer of nanoparticles in the micropattern was carried out by plasma treatment.

We employed thin film blends of diblock copolymers with functional homopolymers as a simple strategy to incorporate organic functional materials into nanodomains of diblock copolymers without serious synthesis. A blend pair of polystyrene–poly(methyl methacrylate) (PS–PMMA) diblock copolymers and poly(vinylidene fluoride) (PVDF) was selected as a model demonstration because PVDF is a well-known ferroelectric polymer and completely miscible with amorphous PMMA. Thin films of symmetric PS–PMMA copolymers provided the nanometer-sized PMMA lamellae, macroscopically parallel to the substrate, in which PVDF chains were dissolved. Thus, amorphous PVDF chains were effectively confined in the PMMA lamellae of thin film blends. The location of PVDF chains in the PMMA lamellae was investigated by the dependence of the lamellar period on the volume fraction of PVDF, from which we found that PVDF chains were localized in the middle of the PMMA lamellae. After the crystallization of PVDF, however, some of PVDF migrated to the surface of the film and formed small crystallites.

The phase behavior of polystyrene-block-poly(n-pentyl methacrylate) copolymers [PS−PnPMA] having various block length ratios was investigated by rheology, transmission electron microscopy (TEM), and small-angle X-ray scattering (SAXS). All of the PS−PnPMA exhibited two transitions: the lower disorder-to-order transition (LDOT) and upper order-to-disorder transition (UODT) occurring at a lower and higher temperature, respectively. Thus, PS−PnPMA is characterized by a closed-loop type of phase behavior. As the volume fraction of PS in PS−PnPMA was decreased from 0.5 to 0.23, the microdomains observed between the LDOT and UODT changed from lamellae (LAM) to hexagonally packed cylinders (HEX) and finally to body-centered-cubic spheres (BCC), similar to other block copolymers exhibiting only an order-to-disorder transition. The rheological properties depended strongly on the type of microdomains within the closed-loop. The storage and loss moduli (G‘ and G‘ ‘) within the closed loop are the highest for a PS−P...

We investigated variations of the domain period of block copolymers by selective staining agents that are used for contrast enhancement in transmission electron microscopy. Employing thin films of symmetric diblock copolymers, homogeneous but selective staining was obtained throughout the film. Moreover, the thin film had a multilayered structure of parallel lamellae with the total film thickness quantized in terms of the lamellar period so that increments of the lamellar period by staining were conveniently and quantitatively evaluated as a function of staining time. In the case of a chemisorbed staining agent of osmium tetroxide for polybutadiene, the lamellar period in thin films of polystyrene-block-polybutadiene was gradually increased with staining time and had 22% increase at the saturation. Similar results were also obtained in the case of thin films of polystyrene-block-poly(methyl methacrylate) by ruthenium tetroxide and polystyrene-block-polyvinyl-pyridine by iodine.

We obtained perpendicular lamellar orientations in thin films of symmetric polystyrene- block -poly(methyl methacrylate), PS- b -PMMA, on self-assembled monolayers (SAMs) of 3-( p -methoxyphenyl)propyltrichlorosilane (MPTS) prepared on silicon wafers. In contrast to completely parallel lamellae on silicon wafers having a native oxide layer, perpendicular lamellae at the MPTS interface with parallel lamellae at the air interface were directly observed by transmission electron microscopy (TEM) in cross-sectional view. The perpendicular lamellae at the MPTS interface were attributed to the non-preferential (neutral) MPTS-covered substrate to both PS and PMMA blocks. The neutrality of the SAMs of MPTS was confirmed by the similar interfacial tension values of the SAMs of MPTS with PS and PMMA, estimated by contact angle measurements.

A highly ordered two-dimensional array of Au nanoparticles over an extended area was synthesized from a near-perfect hexagonal layer of diblock copolymer micelles induced by solvent vapor treatment.

TlGaS2 single crystal were grown by using the Bridgman method. The deep levels of TlGaS2 single crystal were investigated by the TSC (thermally stimulated current) and PlCTS (photoinduced current transient spectroscopy) techniques. The activation energies of the four peaks observed from the TSC curve are (a) 0.18, (b) 0.23, (c) 0.36, and (d) 0.66 eV. Peaks a and b are located below the conduction band and peaks c and d are located above the valence band. The escape frequencies are calculated to be 2.9 × 106, 1.8 × 107, 3.4 × 107, and 5.6 × 1010 s−1, respectively. The PICTS spectra of TlGaS2 single crystal show four deep traps whose activation energies are calculated to be 0.17, 0.23, 0.35, and 0.65 eV, respectively.

We examine the stock market reaction to announcements of corporate name changes for fi rms belonging to Korean chaebols. We fi nd that chaebol-affiliated fi rms changing their non-chaebol-name (a name not including the name of a chaebol) to a chaebol-name (a name including the name of a chaebol) experience a positive stock price reaction on the announcement date. Another noteworthy finding is that the fi rms also earn a statistically signifi cant excess return on the effective date of a name change, as well as on the announcement date. The stock price reaction on the effective date is stronger among stocks experiencing a larger increase in their investor base.

Prior studies argue that overconfidence-driven overreaction leads to return predictability and high trading volume. Motivated by these studies, we propose a measure of continuing overreaction using weighted signed volumes. We find that the strategies of buying stocks with upward continuing overreaction and selling stocks with downward continuing overreaction generate significant positive returns, and our measure of continuing overreaction is a better predictor of future returns than past returns. The results are stronger among stocks primarily held by investors more prone to biased self-attribution. Our results provide direct support for the model of return predictability based on overconfidence and biased self-attribution.

We demonstrate the formation of highly ordered hexagonal arrays of hybridized polystyrene-poly(4-vinyl pyridine), PS-PVP, micelles with controllable size by solvent annealing techniques. Because the formation of hybridized micelles was prohibited in the mixture solutions of two different-sized PS-PVP micelles, single-layered films with bimodal self-assemblies of small and large micelles were fabricated from the mixture solutions by adjusting their mixing ratios. When the single-layered films were solvent annealed by saturated vapor of tetrahydrofuran (THF), on the other hand, small and large PS-PVP micelles in the bimodal self-assemblies merged together to form hybridized micelles. In addition, the hybridized micelles arranged themselves in a highly ordered hexagonal array, the diameter and center-to-center distance of which were precisely adjusted by varying the mixing ratio of small to large micelles in the bimodal assemblies.

Magnetic nanoparticles (MNPs) have been used in various areas, such as in the manufacture of bearings, seals, lubricants, heat carriers, and in printing, recording, and polishing media. [1] One of the rapidlydeveloping research subjects involving MNPs is their application in biological systems, including their application in magnetic resonance imaging (MRI), targeted drug delivery, rapid biological separation, biosensors, and magnetic hyperthermia therapy. [2] The exploration of the interaction between nanostructured materials and living systems is of fundamental and practical interest, and it opens new doors to novel interdisciplinaryresearch field, “nanobioscience”. MNPs exhibited great potential for in vitro and in vivo biomedical application, [3] and the biodistribution of MNPs is stronglyinfluenced bytheir size, charge, and surface chemistry. [4] Recentlypublished reports indicate that magnetic nanoparticles (or microparticles), Fe3O4, conjugated with various targeting molecules or antibodies, can be used to target specific cells in vitro. [5] However, the noncovalent surface modification of nanoparticles

Hexagonal arrangement of iron oxide nanoparticles was fabricated by utilizing a single-layered film of diblock copolymer micelles. The synthesis was directly performed on the solid substrate by oxygen plasma with preserving the dimensional order of micelles so that separate procedures for synthesis and deposition of nanoparticles were not necessary. Since the oxygen plasma treatment also eliminated polymers, pure patterns of iron oxide nanoparticles were obtained. Moreover, easy control over the size of nanoparticles enabled us to selectively create a ferrimagnetic or a superparamagnetic pattern of iron oxide nanoparticles without altering the fabrication process.

We demonstrated the fabrication of electrically anisotropic thin films of alternating polymeric layers and metallic layers in nanometer thickness by utilizing self-assembled nanodomains of symmetric diblock copolymers. Nanometer-thick metal layers macroscopically parallel to the film plane were synthesized by electroless Ag deposition on Au nanoparticles selectively in one of the blocks. Every Ag/Au layer was completely separated by nanometer-thick polymer layers in the direction perpendicular to the film plane. Therefore, the conductivity of the film was highly anisotropic, differing by at least 8 orders of magnitude in directions parallel and perpendicular to the film plane, even though the in-plane conductivity (2.8 x10(-6) S/cm) was in the range of semiconductors. If self-assembled nanodomains of diblock copolymers were not employed, a serial layer-by-layer process for each layer would be required to fabricate such an electrically anisotropic thin film.

We demonstrated a self-assembly of two different kinds of nanoparticles simultaneously directed on a monolayer film of diblock copolymer micelles via physical and chemical arrangements. We first incorporated gold nanoparticles physically around the micelles of a monolayer film of PS-PVP micelles having a short-range hexagonal order. Iron oxide nanoparticles were then synthesized chemically in the PVP core area of the ordered micelles, resulting in a mosaic nanopattern of magnetic iron oxide nanoparticles surrounded by metallic gold nanoparticles. Thus, we were able to direct two kinds of nanoparticles to self-assemble in the specific positions as an example of controlled fabrication of nanometer-sized building blocks.

Purpose : We aimed to determine the ideal age for initiating toilet training and investigate the factors influencing the training. Methods : The study population comprised 1,370 children aged 2-6 years, who visited the pediatric clinics in Jeonju, Iksan, and Gunsan. Their parents were given questionnaires in order to gather data about the types of diapers used, ages when toilet training was initiated and completed for each day and night, its adverse effects, and the educational level and employment and economic status of the mothers. Results : The toilet training initiation age was low for those living in the country, having an elder sibling(s), and using cloth diapers, and for those whose mothers were employed and had a low economic status. The training completion age was 22.9 months when the training was initiated before the age of 18 months; this was lower than the training completion ages of 25.9 and 31.0 months when the training was initiated at the age of 18-24 months and after 25 months, respectively. However, the required durations in these cases were 8.4, 5.6, and 3.8 months, respectively. Encopresis and refusal occurred more often when the training was initiated before the age of 18 months than when initiated after this age. Conclusion : Toilet training should begin at least after the age of 18 months considering the developmental status of infants. It is recommended for the future researchers to develop specific guidelines regarding toilet training.

TlGaS2 and TlGaS2:ErCl3 single crystals were grown by the Bridgman technique. The optical energy band gaps and the deep levels of the as-grown crystals were investigated by the optical absorption, thermally stimulated current (TSC), and, photo-induced current transient spectroscopy (PICTS) spectra. The electron traps (0.18±0.01 eV and 0.23±0.01 eV) and the hole traps (0.36±0.02 eV and 0.66±0.02 eV) are observed in TlGaS2 single crystal. In the case of TlGaS2:ErCl3 single crystal, two deep levels as donors are located at 0.15±0.01 eV and 0.25±0.01 eV and, one deep level as acceptor, at 0.64±0.02 eV.

To identify the manganese related defect levels in GaSe, GaSe:Mn single crystals were grown with various Mn dopant levels using the Bridgman technique and the photoconductivity and photoluminescence properties were investigated. Peaks introduced by the manganese related defects were observed at 1.916 and 1.724 eV in the photoconductivity spectra and at 1.804 eV in the photoluminescence spectra at 80 K. These results allow the calculation of the energies of the A 1 and A 2 centers at 0.348 and 0.156 eV, respectively, above the valence band and a donor level at 0.112 eV below the conduction band. Also, we find that the A 1 and A 2 centers are pinned within the conduction band from measurements of the temperature dependence of the photoconductivity spectra.

Anomalous optical energy gap dependence of the noble Pb 1− x Cd x I 2 single crystal on the CdI 2 mol% has been investigated. The Bridgman method was utilized to grow sample crystals out of polycrystalline PbI 2 powder mixed with CdI 2 powder of various mol% in a vertical furnace. Analysis of the X-ray diffraction patterns shows that the Pb 1− x Cd x I 2 single crystal has the hexagonal close-packed layered structure. The optical energy gap of the Pb 1− x Cd x I 2 single crystal has its minimum value at 0.18 mol% and increases linearly for CdI 2 composition ratios higher than 1 mol%.