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Audio fingerprinting technology is commonly used in the field of automatic content recognition (ACR). Although various audio fingerprinting techniques have previously been proposed, we propose an advanced landmark extraction technique built on gradient-based features. With the widespread use of smart phones, a large number of audio fingerprinting applications are currently running on mobile phones in outdoor environments. As a result, these audio fingerprinting systems suffer from noise interference. To overcome this problem, we propose a novel scheme to effectively extract salient features and identify an audio signal from them. Test results show that our proposed approach can more accurately identify an audio signal in a noisy environment.

The electrical, thermal, optical, and morphological properties of CUO doped Bi 2 O 3 –B 2 O 3 –BaO–ZnO glasses were studied as a PbO-free, low firing transparent dielectric layer for plasma display panels (PDP). CuO improved the transmittance of Bi 2 O 3 –B 2 O 3 –BaO–ZnO by up to 84% in the visible region, eliminating a yellowish color typical of Bi 2 O 3 –B 2 O 3 –BaO–ZnO. A slight absorption within the near infrared (NIR) region was also observed. The glass transition temperature ( T g ), thermal coefficient of expansion (TCE), and root-mean square (rms) roughness of 0.005 wt% CuO doped Bi 2 O 3 –B 2 O 3 –BaO–ZnO were found to be 455 °C, 81.4 × 10 −7 /K, respectively, and 162 ± 14 A, which satisfied the requirements for a transparent dielectric layer for PDP application.

Sn was employed in Ge2Sb2Te5 to accelerate operation speed of phase change random access memory (PRAM). Crystallized Sn-doped Ge2Sb2Te5 showed face centered cubic (fcc) or hexagonal close packed (hcp) structures upon heat treatment, which was similar to that of Ge2Sb2Te5. However, Sn doping increased the phase transformation temperature to hcp of Ge2Sb2Te5. 17 at. % Sn-doped Ge2Sb2Te5 had an accelerated crystallization under laser irradiation and moreover, showed decreased operation time of PRAM compared to that of Ge2Sb2Te5. In addition, 17 at. % Sn-doped Ge2Sb2Te5 showed stable and reversible device performance.

Rapid correction of hyponatremia is frequently associated with increased morbidity and mortality. Therefore, it is important to estimate the proper volume and type of infusate required to increase the serum sodium concentration predictably. The major common management errors during the treatment of hyponatremia are inadequate investigation, treatment with fluid restriction for diuretic-induced hyponatremia and treatment with fluid restriction plus intravenous isotonic saline simultaneously. We present two cases of management errors. One is about the problem of rapid correction of hyponatremia in a patient with sepsis and acute renal failure during continuous renal replacement therapy in the intensive care unit. The other is the case of hypothyroidism in which hyponatremia was aggravated by intravenous infusion of dextrose water and isotonic saline infusion was erroneously used to increase serum sodium concentration.

Bismuth titanate (Bi2Ti2O7) nanotubes were successfully synthesized with an alumina template-based sol-gel technique. As-synthesized nanotubes are smooth and uniform with diameters ranging from 180 to 330 nm and lengths varying from 7 to 12 μm. Extensive characterization of as-prepared samples has been performed using x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), energy-dispersive x-ray spectroscopy (EDS), and selected-area electron diffraction (SAED). Photocatalytic studies indicate that as-prepared nanotubes possess higher photocatalytic activity than the corresponding bulk sample prepared without the use of an alumina template.

We have fabricated white polymer light-emitting devices (WPLEDs) from RGB polymer blending systems using ITO/PEDOT:PSS/blended polymers/LiF/Al structure. The highest current efficiency reached 5.34 cd/A and the maximum brightness value of 27,000 cd/m2 at 11.4 V was obtained. As the green dopant concentration increased, the spectrum deviated from the white because of more energy transfer from host to guest. As a result, the 450 nm blue peak was reduced by increasing green dopant ratio. On the other hand, 600 nm red shoulder peaks were slightly increased at the same conditions. Therefore, red-orange and green electroluminescence emissions are promoted by excitation energy and charge transfer from the blue host polymer to the dopants.

Monodisperse nanocrystalline rhombohedral composites of Fe and Fe3O4 magnetic materials have been obtained employing a reduction reaction, in a flowing gas mixture of H2 and N2, of single-crystalline, submicron-sized α-Fe2O3 rhombohedral precursors. This synthesis is significant in that we were able to create a nanocomposite with hard and soft magnetic phases juxtaposed within one discrete, anisotropic structure. In turn, the precursor hematite rhombohedra of reproducible shape were successfully prepared using a facile, environmentally friendly, large-scale molten-salt reaction. Rhombohedra represent a high-surface-area, anisotropic formulation of an industrially important material (iron oxide), which is an active component of gas sensors, photocatalysts, and other types of catalytic materials. Moreover, the predictive formation of these materials has been investigated through a systematic variation of experimental parameters. Extensive structural characterization of as-prepared samples has been performed...

Vanadia–titania catalysts prepared by a sol–gel method and by supercritical drying showed a very high activity and thermal stability for gas phase oxidation of 1,2-dichlorobenzene (DCB) in the range of 150–600 °C. The selectivity for carbon oxides was kept over 95% unless the reaction temperature was relatively low ( The surface structure of vanadia played a critical role on the catalytic activity, but the structure of crystalline titania was revealed to have exclusive dependency. For the vanadia–titania catalysts with the inherent characteristics of aerogels such as high specific surface area and chemical homogeneity, little bulk vanadia was observed and catalytic activity was maintained or improved due to the formation of surface mono- and poly-vanadates after repeated reactions.

This paper reports on the basic characteristics of the mitochondrial genome of the intertidal copepod Tigriopus sp. from Korea, including its structural organization, base composition of rRNAs and protein-encoding genes, and the secondary structure of tRNAs. We amplified the complete mitochondrial DNA of the intertidal copepod Tigriopus sp. from Korea (sampling site Busan) by long-polymerase chain reaction (long-PCR) with conserved primers and sequenced this mitogenome by primer walking using flanking sequences as sequencing primers. The primer informations were obtained as expressed sequence tags (ESTs) from Tigriopus sp. The resultant Tigriopus sp. mitochondrial DNA sequence was 14,301 bp with a conserved structural organization, compared to that of T. japonicus from Japan with significant differences in several protein-coding regions including rRNAs, although the genomic organization of the mitochondrial genome was identical. In order to investigate biogeographic differences within the genus Tigriopus, we analyzed the CO1 gene by sequencing. This way, we compared several Tigriopus species from Korea, Japan, Hong Kong and Taiwan as well as other related species such as T. californicus, T. brevicornis and T. fulvus. The results further support the notion that the copepods display significantly different genomes within the same genus. These findings provide valuable genomic information for further studies on the population genetics and speciation processes within the genus Tigriopus.

Deubiquitinating enzymes regulate a number of cellular mechanisms including pre-implantation, growth and differentiation, oncogenesis, cell cycle progression, transcriptional activation, and signal transduction. In this study, we have identified a novel human deubiquitinating enzyme gene, USP22, and its mouse homologue, Usp22. They encode 525 amino acids (approximate MW: 60kDa) and contains Cys, Asp (I), His and Asp/Asn (II), the highly conserved domains of the UBP family of deubiquitinating enzymes. The biochemical assay revealed that they have deubiquitinating enzyme activity. Northern blot analysis for USP22 showed moderate expression in various organs including human heart and skeletal muscle, and weak expression in lung and liver. However, Usp22 is expressed strongly in brain and weakly in other organs. We investigated the expression level of Usp22 mRNA and the localization during implantation and early pregnancy by in situ hybridization. Interestingly, Northern blot analysis showed the strong expression of Usp22 between embryonic days E10.5 and E12.5. Whole mount in situ hybridization staining revealed that Usp22 was expressed in the midbrain, forebrain, hindbrain and dorsal root ganglia of embryos at E12.5. Embryos at E12.5 showed the pronounced expression of Usp22 during the early embryonic development, although its expression was not detectable in the gut, liver and heart.

We have fabricated white polymeric light-emitting devices (WPLEDs) from polyfluorene-based (PFO) blue and MEH-PPV polymer blending systems. A device structure of ITO/PEDOT:PSS/Blending polymer/Blue polymer/LiF/Al was employed. This double emissive structure results in the significant improvement of white color shift phenomenon. A current efficiency of 4.67 cd/A (3,900 cd/m2, 6.4 V) and a brightness value of 17,600 cd/m2 at 9.4 V with (0.34, 0.35) CIE coordinates at 5 V and (0.29, 0.29) at 9 V were obtained.

To investigate the impacts of marine pollution on aquatic organisms, we tested the intertidal copepod Tigriopus japonicus as a model species. To analyze the copepods' responses to endocrine-disrupting chemicals (EDCs), we exposed them to two different chemicals: 4,4'-octylphenol (4,4'-OP, 12.5-100 microg/L for 2 h) and polychlorinated biphenyl (PCB, 6.25-25 microg/L for two days). 4,4'-OP was toxic, although exposure time was limited to 2h. After extracting total RNA from the exposed T. japonicus, we performed reverse transcriptase-polymerase chain reaction (RT-PCR) to determine gene expression patterns following chemical exposure. To analyze the gene expression of T. japonicus, we used glutathione S-transferase with GAPDH as an internal control. Of the genes tested using EDC-exposed samples, 4,4'-OP induced upregulation of the glutathione S-transferase (GST) gene, while PCB caused downregulation of the GST gene. These results suggest that the two EDCs act in different manners in T. japonicus.

Traditionally, SWNTs have been prepared by electric arc-discharge, laser ablation, or chemical vapor deposition (CVD) methods, yielding tubes of various diameter and length distributions. However, without exception, as-prepared SWNTs are contaminated with a number of impurities, decreasing the overall yield of usable material. Impurities include transition metal catalysts, such as Fe, Co, and Ni, which are necessary for the growth of SWNTs as well as carbonaceous species such as amorphous carbon, fullerenes, multishell carbon nanocapsules, and nanocrystalline graphite. In this Feature Article, we highlight the role of microscopy in designing and facilitating the interpretation of the success of strategies, including (a) oxidative methods including liquid and gas phase oxidation, (b) chemical functionalization protocols, (c) filtration and chromatography techniques, and (d) microwave heating methods, aimed at rationally purifying single-walled carbon nanotubes.

[Purpose] The aim of the present study was to examine the influence of wobble board training on static balance, with and without vision, of adolescents with Down syndrome (DS). [Subjects] Ten adolescents with DS were recruited for this study. [Methods] Participants performed quiet standing with their eyes open and closed, pre- and post-wobble board training. During quiet standing, the center of pressure (COP) data was recorded using a force plate. To assess the static balance ability of the participants, the 95% confidence ellipse area of COP was calculated. The paired t-test was used to compare the 95% confidence ellipse area of COP between the eyes open and closed conditions, and between pre- and post-training. [Results] Although there was no significant difference in the 95% confidence ellipse area of COP between with and without vision, the 95% confidence ellipse area of COP decreased significantly after wobble board training. [Conclusion] These findings suggest that wobble board training is an effective at improving the static balance ability of adolescents with DS.

The performance of the platinum–cobalt catalysts in a carbon monoxide preferential oxidation (PROX) reactor was investigated for polymer electrolyte fuel cell systems. First, the PROX reaction was analyzed based on two major reactions involved in it, i.e., oxidation of carbon monoxide and the H 2 –O 2 reaction. Both reactions were affected by the other reaction depending on the reaction temperature regions, but the extent of the influence is not so large. The platinum–cobalt catalysts were found to exhibit high performance in PROX of carbon monoxide in rich hydrogen as a result of catalytic synergy effect between platinum and cobalt. In order to improve such synergy effect, the catalysts were prepared by sol–gel method and subsequent supercritical drying. The platinum–cobalt catalysts prepared by the single step sol–gel procedure exhibited higher activity for PROX than the catalysts prepared by the conventional impregnation. Supercritical drying preserved the active species of platinum–cobalt phase, therefore, the platinum–cobalt composite aerogel catalyst exhibited excellent ability for the carbon monoxide removal.

Various catalysts containing different catalytic materials, supports, and additives were tested for the preferential oxidation (PROX) of carbon monoxide from a hydrogen-rich gas stream. The results were analyzed based on three reactions involved in the PROX: oxidation of carbon monoxide, H 2 –O 2 reaction, and methanation. The PROX reactions were performed in two reaction systems, one for catalyst screening and kinetic study and the other for simulation of the catalytic performance under real reaction conditions. The performances of PROX on different catalysts, varying active components, supports, and additives, were ranked in terms of carbon monoxide conversion and hydrogen consumption. Base metal added platinum catalysts exhibited excellent ability for the carbon monoxide removal. TPR results indicated that a new active species was formed resulting in the enhancement of catalytic activity. PtCo/Al 2 O 3 was tested with a simulated steam-reformed fuel for confirmation of its high activity. The effect of operating conditions was analyzed on the PtCo/Al 2 O 3 , and the optimum conditions for PROX were obtained.

Preferential oxidation (PROX) of carbon monoxide from a hydrogen-rich gas stream was performed over sodium-added platinum-cobalt catalyst. The process was analyzed based on the two major reactions involved in PROX, viz. the oxidation of carbon monoxide and the H2–O2 reaction. The modification of sodium enhances the performance of platinum-cobalt catalysts greatly, whereas the extent of the enhancement is relatively small for platinum catalysts. Selectivity for carbon monoxide oxidation is not influenced by sodium addition for any of the platinum and platinum-cobalt catalysts. The BET surface area of alumina is reduced by sodium addition, because sodium forms Na–O–Al bonds due to the migration of sodium ions into the alumina support. The incorporation of sodium with alumina inhibits the formation of the surface spinel cobalt species and promotes the formation of the Pt–Co bimetallic interphase.

[Purpose] This study investigated the effects of walking with talus taping on the ankle dorsiflexion passive range of motion (DF PROM) in individuals with limited ankle DF PROM. [Subjects] Fifteen ankles with limited DF PROM were examined. [Methods] After rigid strapping tape was applied to the ankles from the talus to the calcaneus, progressing posteriorly and inferiorly, the subjects walked on a walkway for 10 min. Using a goniometer, the ankle DF PROM was measured with the knee extended before and after walking with talus taping. The difference in ankle DF PROM between before and after walking with talus taping was analyzed using the paired t-test. [Results] The ankle DF PROM was significantly increased after walking with talus taping. [Conclusion] Our findings indicate that walking with talus taping is effective for increasing the ankle DF PROM in individuals with limited ankle DF PROM.

Chlorella is a eukaryotic microalgae which shares metabolic pathways with higher plants. These charac-teristics make chlorella a potential candidate for eukaryotic overexpression systems. Recently, a foreign flounder growth hormone gene was stably introduced and expressed in transformed Chlorella ellipsoidea by using a modified plant transformation vector that contains cauliflower mosaic virus (CaMV) 35S pro-moter and the phleomycin resistant Sh ble gene as a selection marker. In this study, this same vector was modified by incorporating a promoter and a 3` UTR region of the 33kDa peptide gene from a chlorella virus that was isolated in our laboratory. The 33kDa gene promoter was used to replace the 35S promoter and the 3` UTR was introduced to separate the target gene and downstream Sh ble gene. Three different chlorella transformation vectors containing human erythropoietin (EPO) gene were constructed. The mp335EPO vector consists of a promoter from the 33kDa peptide gene, whereas the mp3353EPO vector contains the same promoter from the 33kDa peptide gene and its 3` UTR. The mp35S33pEPO vector contains the 35S promoter and the 3` UTR from the 33 kDa peptide gene. There was no significant difference in the expression levels of EPO protein in chlorella cells transformed with either of three of the transformation vectors. These data indicate that the promoters from the chlorella virus are comparable to the most common CaMV 35S promoter. Furthermore, these data suggest that other promoters from this virus can be used in future construction of chlorella transformation system for higher expression of target proteins.

We synthesized a cDNA library from the intertidal copepod Tigriopus japonicus, converted it to phagemids and sequenced expressed sequence tags (ESTs). Of these, Tigriopus translationally controlled tumor protein/histamine releasing factor (TCTP/HRF) was further characterized. The Tigriopus TCTP/HRF gene encoded 172 amino acid residues and showed high similarity to Drosophila but moderate similarity to other annelids (e.g. Brugia, Wuchereria and C. elegans). The Tigriopus TCTP/HRF gene appeared in the same clade as the annelids. Here, we describe the analysis of the Tigriopus TCTP/HRF gene.

The use of flexible diquaternary alkylammonium ions (C2H5)3N+(CH2)nN+(C2H5)3 (Et6-diquat-n with n=3–10) as structure-directing agents for zeolite synthesis in the presence of alkali metal cation is described. Among the organic structure-directing agents studied here, a considerable diversity in the phase selectivity was observed only for the Et6-diquat-5 ion: this cation can produce five different zeolite structures (i.e., P1, SSZ-16, SUZ-4, ZSM-57, and mordenite), depending on the oxide composition of synthesis mixtures. Analysis of the variable-temperature 1H CRAMPS NMR spectra obtained from the Et6-diquat-5 molecules in these five zeolites reveals that the host–guest interactions occurring within the respective materials maintain in a manner different from one another even at 160 °C at which the zeolite hosts crystallize.

High-surface-area ruthenium oxide aerogels with pronounced mesoporosity are prepared by carbon dioxide supercritical drying of alcogels by a non-alkoxide sol–gel process with ruthenium chloride as a precursor and epoxide as a proton scavenger. The influence of various sol–gel preparation parameters both on gel formation and the textural properties and voltammetric response of the resulting ruthenium oxide aerogels are investigated systematically. The un-calcined ruthenium oxide aerogel in the amorphous phase possesses a surface area in excess of 350 m 2 g −1 has a specific capacitance as high as 595 F g −1 .

Cryogel and aerogel Pt-Ru/C were synthesized by the sol-gel process for the electrooxidation of methanol. From XRD analysis, it was found that the catalysts had highly dispersed Pt-Ru alloys on carbon support although high temperature treatments have been conducted. Electrocatalytic activities of 3 type aerogel catalysts were investigated in half cell experiments by cyclic voltammetry. Among them, Phloroglucinol-Formaldehyde(PF) type catalyst shows the highest activity. From the results of deactivation test for each catalysts, the aerogel catalysts are found to have excellent durability compared with those prepared by colloidal method.

Magnetic and Mossbauer characterization of single crystalline, sub-micron sized Bi₂Fe₄O₉ cubes has been performed using SQUID magnetometry and transmission Mossbauer spectroscopy in the temperature range of 4.2 K ≤ T ≤ 300 K. A broad magnetic phase transition from the paramagnetic to the anti-ferromagnetic state is observed below 250 K, with the Mossbauer spectra exhibiting a superposition of magnetic, collapsed and quadrupolar spectra in the transition region of 200 K < T < 245 K. Room temperature Mossbauer spectra obtained in transmission geometry are identical to those recorded in back-scattering geometry via conversion electron Mossbauer spectroscopy, indicating the absence of strain at the surface. A small hysteresis loop is observed in SQUID measurements at 5 K, attributable to the presence of weak-ferromagnetism arising from the canting of Fe³⁺ ion sublattices in the antiferromagnetic matrix.

Background: An increase in the obese adolescent population is being recognized as a serious medical and social problem. The present study aimed to examine the association between neighborhood socioeconomic status (SES) and obesity in Korean adolescents based on total available resources and local social inequality models. Methods: The present study used data from the 2013 Korea Youth Risk Behavior Web-based Survey in analyzing 72,438 Korean adolescents aged 12–18. The analysis investigated obesity odds ratio (OR) according to neighborhood SES adjusted for age and individual SES indices, which included family affluence scale (FAS), education level of parents, cohabitation with parents, and weekly allowance. Obesity OR was investigated according to neighborhood SES by FAS, and according to FAS by neighborhood SES. Results: After adjusting for age and individual SES variables, there was no significant association between neighborhood SES and adolescent obesity for either boys or girls. However, girls in the high FAS group showed a pattern of lower neighborhood SES being associated with a significant increase in risk of obesity; in the high neighborhood SES group, boys showed a pattern of higher FAS being associated with a significant increase in risk of obesity, whereas girls show a pattern of decrease. Conclusion: Although limited, the present study demonstrated that some girl groups exhibited a pattern of lower neighborhood SES being associated with an increase in risk of obesity, as well as a gender-based difference in risk of obesity by individual SES. Therefore, measures to prevent adolescent obesity should be established with consideration for differences in risk according to individual and neighborhood SES.

Highly dispersed nickel–titania composite aerogel catalysts have been prepared by CO 2 supercritical drying of alcogels obtained by the sol–gel process. The effect of heat treatment conditions on the textural and structural properties of the resulting aerogels was investigated by nitrogen adsorption–desorption, TG/DTA, XRD and TEM. The nickel–titania composite aerogel calcined and reduced under carefully controlled conditions exhibited an excellent catalytic performance for the liquid-phase hydrogenation of benzophenone to benzhydrol.

The electrorheological (ER) and dielectric behaviors of the polypyrrole(PPy)-coated poly(ethyl methacrylate)(PEMA) suspensions in mineral oil were investigated. PPy was coated on PEMA particles to enhance the particle polarization, which would lead to the enhanced ER response. Various PPy-coated PEMA particles were synthesized by controlling the oxidant amount during the pyrrole polymerization, and the ER responses of their suspensions were investigated. The ER response initially increases with the oxidant amount, passes through a maximum, and then decreases with the oxidant amount. The initial increase in the ER response with oxidant amounts is due to the enhanced particle polarization with the increased particle surface conductivity. The dielectric properties of the corresponding suspensions support that the ER enhancement arises from the enhanced particle polarization. The decrease in the ER response at large oxidant amounts seems to arise from the increased conduction between the PPy-coated PEMA particles.

Mg-doped WO3 with band gap energy of about 2.6 eV is a viable photocatalyst for visible light-induced water splitting in the presence of hole scavengers. The conduction band edge position of p-type Mg-doped WO3 was -2.7 V versus SCE at pH 12. By doping Mg on WO3, the conduction and valence band positions were shifted by 2.25 V negatively, leading to a conduction band edge position which was negative enough for H+ ions to be reduced thermodynamically, with little change in band gap energy. The negative shift in band position might be ascribed to lowering of the effective electron affinity of WO3 by doping Mg with a very low electron affinity.

This study utilized functional magnetic resonance imaging (fMRI) to discriminate brain activation patterns associated with the effect of distraction during working memory (WM) maintenance for human faces in healthy controls and patients with schizophrenia. Event-related fMRI data were obtained while the subjects performed WM maintenance in a delayed-response WM task with task-irrelevant distracters. Compared with healthy controls, patients showed significantly decreased activities in the superior frontal gyrus, dorsolateral prefrontal cortex (DLPFC), ventrolateral prefrontal cortex, anterior cingulate cortex, inferior parietal gyrus, and fusiform gyrus during the delayed-response WM task with human face distracters. The blood-oxygen-level-dependent signal changes in the DLPFC were negatively correlated with both of the scores of the Positive Subscale and General Psychopathology Subscale under the Positive and Negative Syndrome Scale during the WM maintenance for the human faces in the patients. This study will be helpful in understanding the neural mechanisms in the general impairment of the inhibition control in schizophrenia.

Acoustic data transmission is a technique used to imperceptibly deliver data on sound waves. This paper presents a new approach to embed the data in a complex quadrature mirror filterbank by adopting phase shift keying modulation. The evaluation results show that the proposed method successfully delivers the data overcoming severe acoustic channel distortion with a low bit error rate.

High power densities have been obtained from MFC reactors having a purple color characteristic of Rhodopseudomonas. We investigated the microbial community structure and population in developed purple MFC medium (DPMM) and MFC effluent (DPME) using 16S rRNA pyrosequencing. In DPMM, dominant bacteria were Comamonas (44.6%), Rhodopseudomonas (19.5%) and Pseudomonas (17.2%). The bacterial community of DPME mainly consisted of bacteria related to Rhodopseudomonas (72.2%). Hydrogen oxidizing bacteria were identified in both purple-colored samples: Hydrogenophaga and Sphaerochaeta in the DPMM, and Arcobacter, unclassified Ignavibacteriaceae, Acinetobacter, Desulfovibrio and Wolinella in the DPME. The methanogenic community of both purple-colored samples was dominated by hydrogenotrophic methanogens including Methanobacterium, Methanobrevibacter and Methanocorpusculum with significantly lower numbers of Methanosarcina. These results suggeste that hydrogen is actively produced by Rhodopseudomonas that leads to the dominance of hydrogen consuming microorganisms in both purple-colored samples. The syntrophic relationship between Rhodopseudomonas and hydrogenotrophic microbes might be important for producing high power density in the acetate-fed MFC under light conditions.

Mesoporous and well-dispersed nickel–alumina composite aerogels with high surface area have been prepared by CO 2 supercritical drying of alcogels obtained by the fast sol–gel process. They were evaluated as catalysts in a batch reactor for the liquid-phase hydrogenation of benzophenone and soybean oil and showed excellent activity and accessibility of the metal particles. They were also characterized by nitrogen adsorption–desorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM) to explain their excellent catalytic performance in comparison with other alumina-supported nickel catalysts.

CO2 reforming of CH4 was carried out over Ni–alumina aerogel catalysts prepared with various Ni loadings. The preparation of alumina supported Ni catalysts via sol–gel synthesis and subsequent supercritical drying led to the formation of very small metal particles, which are evenly distributed over the alumina support. The activity of the aerogel catalysts increased along with increasing metal loading, and eventually, the SAA25 (0.25 in Ni/Al mole ratio) catalyst exhibited the high activity comparable to that of a 5 wt.% Ru/alumina catalyst (ESCAT44, Engelhard). Compared to the alumina-supported Ni catalyst prepared by conventional impregnation method, Ni–alumina aerogel catalysts showed a remarkably low coking rate due to highly dispersed metal particles. From TEM micrograph studies, it was observed that the formation of filamentous carbon was significantly influenced by the metal particle size and proceeded mostly over the metal particles larger than 7 nm. The loss of catalytic activity at 973 K was mainly caused by coke deposition and sintering.

Aerogels of titania, zirconia, niobia, and silica were prepared by CO2 supercritical drying of the corresponding alcogels. Their porous texture could be modified by further aging of the alcogels. This kind of textural modification was found to be different according to the nature of the metal precursor and sol-gel conditions.

Barium (Ba)-substituted CsTiSi2O6.5 materials of two types, CsxBa1−xTiSi2O(7−x/2) and CsxBa(1−x)/2TiSi2O6.5 were synthesized with the pollucite structure with 1≥x≥0.6. When the Ba-substituted precursor materials were heat treated to 850°C for 4 h, a mixture of amorphous and unidentifiable phases formed. However, with the addition of 10 wt% of crystalline CsTiSi2O6.5 to the Ba-containing precursors, nearly single-phase pollucite was obtained after 20 h at 750°C for x≥0.6. The added crystalline CsTiSi2O6.5 particles act as nuclei that allow the Ba-containing materials to crystallize into the pollucite phase and to avoid the formation of unwanted phases that would otherwise nucleate and grow. These new materials can be used to study the stability of CsTiSi2O6.5 as a durable ceramic waste form, which could accommodate with time both Cs and its decay product, Ba.

We propose ZnxSb100-x alloys as a phase-change material for application in nonvolatile memory, phase-change random access memory (PRAM). The ZnxSb100-x alloys showed electrical switching between amorphous and crystalline states and their amorphous state showed sheet resistances 104-fold higher than that of the crystalline state in 100 nm ZnxSb100-x films. Zn doping reinforced the amorphous stability of the ZnxSb100-x alloys, which adjusted their switching characteristics. Increasing the concentration of Zn increased the crystallization temperature of the ZnxSb100-x alloys. PRAM (λ= 0.5 µm) using the Zn17Sb83 film presented reversible program performances between set and reset. The minimum time for set switching was 140 ns and the required current for reset switching was 9.6 mA in Zn17Sb83 PRAM.

Mesoporous nickel–alumina aerogel catalysts with high surface area have been prepared by CO2 supercritical drying of alcogels obtained by the fast sol–gel process. The nickel phase was uniformly distributed in the alumina gel network from transparent monolithic nickel–alumina co-gels by using nickel acetate as a metal precursor. The nickel–alumina aerogel catalysts prepared were characterized by nitrogen adsorption–desorption, TG/DTA, and reaction test, and their properties were compared with those of conventionally impregnated catalysts. Alumina aerogel-based nickel catalysts exhibited good activity and marked stability against coking in methane dry reforming.

The effect of bias voltage on characteristics of ZnO thin films deposited by the electron cyclotron resonance plasma-enhanced chemical vapor deposition (ECR-PECVD) method was investigated. The structural, optical and electrical properties of ZnO thin films were studied as a function of O2/dielthylzinc ratio and applied bias voltage. Applying –600 V bias voltage on the substrate during deposition can reduce the sheet resistance by a magnitude of 104 without deteriorating the optical transmittance. The optical band gap was increased from 3.36 to 3.54 eV with bias voltage increase. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

An all-oxide transparent p–n heterojunction on a glass substrate was fabricated. The structure of the diode was ITO electrode/p-CuAlO2/n-ZnO/In electrode on the glass substrate. The p-CuAlO2 thin film was deposited by e-beam evaporation, which was annealed by the wet-oxidation method. The p–n heterojunction thin film diode showed rectifying current–voltage characteristics, dominated in forward bias by the flow of space-charge-limited current. The ratio of forward current to the reverse current exceeded 40 within the range of applied voltages of –4.0 to +4.0 V and the turn-on voltage was 0.3 V. Optical transmission of the diode was about 40% in the visible range. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

We proposed a method for estimating the position of mono channel microphones using the sound from loudspeakers with hidden time synchronization waveforms in the audio signal. Unlike previous studies based on the SS (Spread Spectrum) technique, we used OFDM (Orthogonal Frequency Division Multiplexing) time synchronization signal embedded in the sound, maintaining the inaudibility of the embedded signal. While the microphone detects the time synchronization waveform, users remain unaware of the hidden time synchronization signal. With this hidden signal, we can successfully obtain the location of the microphone while the music is playing. We have anticipated various applications of our proposed method such as a configuration of multichannel audio systems or spotting target locations for private listening zones generated by a speaker array.

Titania, zirconia, and niobia aerogels were prepared by the sol−gel synthesis from alcoholic metal alkoxide solutions under acidic conditions and the subsequent supercritical drying with carbon dioxide. At a stoichiometric amount of water and a constant alkoxide concentration the nitric acid contents were varied to examine the characteristics of gel formation behavior and the produced aerogel properties. The range of acid content in which transparent polymeric gels were obtained was determined. Under these conditions there was little effect of acid content on the surface area of their calcined aerogel samples. On the other hand, the pore size distributions were significantly affected by the acid contents. The resulting titania, zirconia, and niobia aerogels, after calcination at 773 K for 2 h, had BET surface areas of about 200, 100, and 200 m2/g, respectively, and relatively narrow pore size distributions in the mesopore region. The results suggest a simple way to control the pore sizes of the high-surfa...

연구배경: 자살은 우리나라 10대 인구 사망원인 중 1위로알려져 있으며, 흡연은 청소년 자살의 위험요인 중 하나로보고되고 있다. 본 연구는 청소년건강행태온라인조사를 이용하여 흡연 및 흡연량과 자살 관련 행동과의 연관성을 알아보고자 한다. 방법:2016년 제12차 청소년건강행태온라인조사를 이용하여, 청소년의 흡연 여부 및 흡연량과 자살생각, 자살계획, 자살시도 여부를 알아보았다. 조사 참여자인 65,528명을 대상으로 현재 흡연자, 과거 흡연자, 비흡연자로 나누고, 현재 흡연자 4,012명을 흡연량에 따라 9개비 이하군, 10-19개비군, 20개비 이상군으로 분류하였고, 자살생각, 자살계획, 자살시도와의 연관성을 다변량 로지스틱회귀분석을 사용하여 알아보았다. 결과: 모든 혼란변수들을 통제하여 분석한 결과, 현재 흡연자는 비흡연자, 과거 흡연자에 비해 자살생각과의 교차비가 1.143 (CI 1.020-1.281)으로 나타났으며, 자살계획, 자살시도의 교차비도 통계적으로 유의하게 높게 나타났다. 또한 9개비 이하군보다 20개비 이상군에서 자살 관련 행동의 교차비는 모두 각각 유의하게 높게 나타났다. 결론: 본 연구를 통해 청소년의 흡연과 흡연량은 자살생각, 자살계획, 자살시도에 영향을 주는 요인임을 알 수 있었고, 이 결과를 고려한 자살 예방 전략 수립이 필요할 것이다.

Background Menopause contributes to an increase in visceral fat mass and a decrease in muscle protein synthesis. Therefore, we performed this study to examine their relationship how effect the changes of body composition as obesity and sarcopenia on metabolic syndrome (MS) as a predictor of cardiovascular disease in postmenopausal women. Methods Using data from the Korean National Health and Nutrition Examination Survey (KNHANES) from 2008 to 2011, we estimated that 4,183 postmenopausal women underwent dual energy X-ray absorptiometry scans. Sarcopenia was defined as an appendicular skeletal muscle mass divided by body weight that was less than 1 standard deviation below the sex specific mean for the young reference group. After classification into four groups, the results were adjusted with menopausal age and hormonal treatment. The relationship between sarcopenic obesity (SO) and MS in postmenopausal women was analyzed by logistic regression analysis in a complex sampling. Results In an unadjusted model, the odds ratio (OR) of MS for sarcopenia was 1.94 (95% confidence interval [CI], 1.52-2.49); the obesity group had an OR of 4.55 (95% CI, 3.63-5.71); and distinctly, the SO group had an OR of 6.26 (95% CI, 5.10-7.70). Even though there was controlling for variable adjustment, no definite difference was seen in the results. Conclusions Sarcopenia and obesity were associated with MS independent of other metabolic impairment risk factors in both early menopausal and postmenopausal women. The results showed that, in particular, the prevalence of MS has increased more in postmenopausal women compared with previous research.

BACKGROUND: Understanding the effects of pretreatment on anaerobic digestion of sludge waste from wastewater treatment plants is becoming increasingly important, as impetus moves towards the utilization of sludge for renewable energy production. Although the field of sludge pretreatment has progressed significantly over the past decade, critical questions concerning the underlying microbial interactions remain unanswered. In this study, a metagenomic approach was adopted to investigate the microbial composition and gene content contributing to enhanced biogas production from sludge subjected to a novel pretreatment method (maintaining pH at 10 for 8 days) compared to other documented methods (ultrasonic, thermal and thermal-alkaline). RESULTS: Our results showed that pretreated sludge attained a maximum methane yield approximately 4-fold higher than that of the blank un-pretreated sludge set-up at day 17. Both the microbial and metabolic consortium shifted extensively towards enhanced biodegradation subsequent to pretreatment, providing insight for the enhanced methane yield. The prevalence of Methanosaeta thermophila and Methanothermobacter thermautotrophicus, together with the functional affiliation of enzymes-encoding genes suggested an acetoclastic and hydrogenotrophic methanogenesis pathway. Additionally, an alternative enzymology in Methanosaeta was observed. CONCLUSIONS: This study is the first to provide a microbiological understanding of improved biogas production subsequent to a novel waste sludge pretreatment method. The knowledge garnered will assist the design of more efficient pretreatment methods for biogas production in the future., published_or_final_version

We combine a wide variety of experimental techniques to analyze two heretofore mysterious phase transitions in multiferroic bismuth ferrite at low temperature. Raman spectroscopy, resonant ultrasound spectroscopy, EPR, X-ray lattice constant measurements, conductivity and dielectric response, specific heat and pyroelectric data have been collected for two different types of samples: single crystals and, in order to maximize surface/volume ratio to enhance surface phase transition effects, BiFeO3 nanotubes were also studied. The transition at T=140.3K is shown to be a surface phase transition, with an associated sharp change in lattice parameter and charge density at the surface. Meanwhile, the 201K anomaly appears to signal the onset of glassy behaviour., submitted to PRB

Aging was found to be an important step for obtaining high-surface-area zirconia aerogels prepared by the sol−gel method using zirconium n-propoxide and subsequent supercritical drying with carbon dioxide. A narrow and much sharper pore size distribution of calcined zirconia aerogels could be obtained only after extended aging.