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Limited light absorption beyond the UV region and rapid photocarrier recombination are critical impediments for the improved photocatalytic performance of carbon quantum dots (CQDs) under visible-light irradiation. Herein, we demonstrate single-step microwave-assisted syntheses of O-CQDs (typical CQDs terminated by carboxylic and hydroxyl functional groups) from a sucrose precursor and Cl-doped CQDs (Cl-CQDs) from a sucralose precursor in short reaction times and without using obligatory strong acids for Cl doping. The doping of Cl into the CQDs is observed to widen the absorption range and facilitate an enhanced separation of photoexcited charge carriers, which is confirmed by the results of optical absorption, photothermal response, and pump-probe ultrafast transient absorption spectroscopy measurements of the O-CQDs and Cl-CQDs. The photoexcited charge carriers with their longer lifetimes in Cl-CQDs enabled the quick degradation of methylene blue dye, rapid conversion of Ag+ ions to metallic Ag nanoparticles on the CQD surfaces, and reduction of GO to a well-dispersed rGO through the photoelectron transfer reactions under visible-light irradiation. The facile Cl doping strategy, hybridization of Ag nanoparticles or rGO to CQDs, and the elevated charge separation mechanism would open up new avenues in designing CQD-based materials for futuristic applications.

Limited light absorption beyond the UV region and rapid photocarrier recombination are critical impediments for the improved photocatalytic performance of carbon quantum dots (CQDs) under visible-light irradiation. Herein, we demonstrate single-step microwave-assisted syntheses of O-CQDs (typical CQDs terminated by carboxylic and hydroxyl functional groups) from a sucrose precursor and Cl-doped CQDs (Cl-CQDs) from a sucralose precursor in short reaction times and without using obligatory strong acids for Cl doping. The doping of Cl into the CQDs is observed to widen the absorption range and facilitate an enhanced separation of photoexcited charge carriers, which is confirmed by the results of optical absorption, photothermal response, and pump-probe ultrafast transient absorption spectroscopy measurements of the O-CQDs and Cl-CQDs. The photoexcited charge carriers with their longer lifetimes in Cl-CQDs enabled the quick degradation of methylene blue dye, rapid conversion of Ag

This preliminary study focuses on investigating whether digital literacy, which is termed ‘diteracy,’ can be measured and how it relates to the conventional concepts and terms of literacy and numeracy by proxies of math and language achievement. First, the results of this study indicated relatively higher diteracy scores of the sixth-grade elementary students and the third-grade secondary ones. While no significant relations were found in terms of smart device using experiences of elementary students, the diteracy scores of the secondary ones indicated higher level of diteracy in some sub-components. Second, math scores are found to have more relations with diteracy than language scores.

To the best of our knowledge, no study has systematically reviewed and analyzed the research trends of wild-simulated ginseng (WSG) used for food or medicinal purposes in many countries. WSG, a non-timber forest product, has been traditionally produced using agroforestry practices, and it has been consumed in various ways for a long time. WSG has a great demand in the market due to its medicinal effects, particularly in improving forest livelihoods and human health. Due to the significance of WSG, we conducted this research to explore the global research trends on WSG using systematic review methodology and keyword analysis. We used two international academic databases, the Web of Science and SCOPUS, to extract 115 peer-reviewed articles published from 1982 to 2020. The research subjects, target countries, and keywords were analyzed. Our results indicate four categories of WSG research subjects, namely growth conditions, components, effects on humans/animals, and the environment of WSG, and the case studies were mainly from the Republic of Korea, China, and the USA. Through topic modelling, research keywords were classified into five groups, namely medicinal effects, metabolite analysis, genetic diversity, cultivation conditions, and bioactive compounds. We observed that the research focus on WSG changed from the biological properties and cultivation conditions of WSG to the precise identification and characterization of bioactive metabolites of WSG. This change indicates an increased academic interest in the value-added utilization of WSG.

The ladder-like polysilsesquioxanes containing both the bio-mimicking adhesive polycatechol and polyethylene oxide (CA-PEO-LPSQ) were synthesized as an organic-inorganic hybrid material and applied as a surface modifier for the preparation of a compatible polyethylene (PE) separator in high performing lithium ion batteries (LIBs). The dip-coating of CA-PEO-LPSQ onto PE (PE-M) separator was optimized at different alkaline pH values. The PE-M separator contained an inorganic ladder-like polysilsesquioxane-based backbone chain with organic moieties PEO and catechol acting as functional groups for enhancing the surface wettability, lithium ion conductivity, and thermal and electrochemical stability. The LIBs fabricated using PE-M as the separator, LiCoO2 as the cathode, and Li metal foil as the anode showed excellent capacity retention of 96% and 82% after the first cycle and 300th cycle at 0.5C rate, respectively, when compared to bare a PE separator exhibiting 95% and 15%, respectively.

Agroforestry is an intensive land management system that integrates trees into land already used for crop and animal farming. This provides a diverse range of ecosystem services by bridging the gaps between agriculture, forestry, and animal husbandry. It is an important approach to improve the environmental, economic, and social benefits of complex social&ndash, ecological systems in the Asia-Pacific region. This paper aims to examine the research trends in agroforestry and the current state of knowledge, as well as the research gaps in the ecosystem services of agroforestry in this region. A systematic mapping methodology was applied, where analysis units were academic articles related to agroforestry practices in the Asia-Pacific region. The articles published between 1970 and 2018 were collected through the international specialized academic database, SCOPUS. They were coded according to the types of agroforestry practices and ecosystem services. The research result indicates silvorable systems, especially plantation crop combinations, tree management, habitats for species, biological controls, and maintenance of genetic diversity and gene-pools, are the most prominent in the agroforestry research from the Asia-Pacific region. Approximately 60% of all research articles include case studies from India, China, Indonesia, and Australia. Research on agroforestry has changed following the international discourse on climate change and biodiversity. Therefore, this systematic map improves our understanding of the nature, volume, and characteristics of the research on ecosystem services with regard to agroforestry in the Asia-Pacific region. It provides scholars with a springboard for further meta-analysis or research on agroforestry and ecosystem services.

Highly conducting poly(3,4-ethylenedioxythiophene) (PEDOT) nanotubes were fabricated by vapor deposition polymerization using anodic aluminum oxide (AAO) nanopororus template. Highly ordered PEDOT nanotube arrays with high respect ratios were produced using this process. The nanoscale diameter and microscale length of the nanotubes were controlled by the pore sizes and depths of the AAO membranes, respectively. The PEDOT nanotubes in the bulk sample had a very high conductivity of 2,000 S/cm. Raman and X-ray photoelectron spectroscopies, transmission and scanning electron microscopies, and atomic force microscopy were used to determine the structure as well as the electrical and optical properties of the PEDOT nanotubes.

Rapid progress in nanotechnology has made it increasingly easier to nanostructure metal materials. This paper describes the formation of uniform silver nanowires by reducing silver acetate with PLLA polymer. The silver nanowires were prepared by wetting a porous template at 350 °C using 1.5 wt.% CH2Cl2 solution containing PLLA/silver acetate in a ratio of 1:1. A thermal analysis in the temperature range of 100 °C to 400 °C was carried out by a differential scanning calorimeter (DSC). An exothermic reaction peak associated with pure silver occurred at 352 °C at a heating rate of 5 °C/min. From the attenuated total reflectance (ATR) spectra analysis of the silver and PLLA composites, it was obtained that the absorption peak of the PLLA became weak by heating to successively higher temperatures in the range of 230 °C to 350 °C. The DSC and ATR results showed that the PLLA can be directly and easily removed at 350 °C, leaving the pure metal inside the pores. The silver nanowires consisted of nanoparticles whose average diameter was about 26.5 nm. And those nanowires with an aspect ratio of about 13 showed an UV-vis absorption peak, which is attributed to the surface plasmon excitation at 350 nm and 377 nm.

TiO2 nanotube layers can be formed with titanium in the electrolytes containing fluoride by electrochemical method. The role of fluoride ion, the crystallinity of the anodic oxide, and the chemical state were investigated. The results show the anodic film is composed of oxide and a little amount of hydroxide. The presence of F− ions leads to chemical dissolution of Ti oxide layer and prevents hydroxide precipitation. Consequently, chemical dissolution rate increases with increasing the fluoride content in the range of 0–2% (in mass fraction) because F− ions in electrolyte attack the interface and allow the ions of the electrolyte to easily penetrate into the interface. The as-anodized TiO2 nanotubes exhibit an amorphous structure. Thermally treated nanotubes are composed of mixtures of the anatase and rutile phases.

Mesoporous titanium dioxide films were fabricated on titanium plates by micro-arc oxidation method. To increase the photocatalytic activity of the films, NH4NO3 was added to the H2SO4 solution, and anodizing was carried out at high voltages using a DC power supply. The crystal structure, chemical composition, surface morphology and the optical property of the films were investigated by XPS, XRD, UV-VIS spectroscopy and SEM. The photocatalytic activity of the films was evaluated by the decomposition of aniline blue, and the activity of the films for the degradation turned out to be improved by the additives to the electrolyte solution. The enhanced photocatalytic activity might result from the increased porosity and nitrate ion incorporation into the anodic films by micro arcing, and thereby the TiO2 layer might exhibit an improved absorption property for the visible light.

We present a wet etching process to fabricate good vertical mesa structures that result in high quality (Q) factors up to 2×104, important for smooth sidewall cavities such as the photonic quantum ring (PQR) laser. Q factor analyses also indicate that it can be improved much more once the internal scattering from the wafer materials is minimized. We use an etching solution of H3PO4:CH3OH:H2O2 with a volume ratio of 3:1:1, and a single-layer photoresist etch mask for etching GaAs∕AlGaAs structures of the PQR laser several micrometer deep. As the etching temperature is varied from 20to40°C, the etched surface roughness decreases from 4.690to0.703nm according to scanning electron microscope and atomic force microscopy studies. From the activation energy analysis for the above etching process and the temperature dependence, the etching process is shown to be reaction limited. The PQR lasers with an active diameter of 10μm, fabricated by the wet etching process, show the spectral linewidth of 0.04nm. Three-dim...

A novel thinning process was proposed for the preparation of bonded and etched silicon-on-insulator (BE-SOI) wafers with high quality and good thickness uniformity by adopting a spin etching and subsequent selective etching as a thinning process. A solution comprising HNO3, HF, H3PO4 and H2SO4 was used for the spin etching process. The spin etching process removed the damaged layer originating from a back-grinding process, which simultaneously yielded SOI wafers with better thickness uniformity than usual back-ground ones. Selective etching adopting a layer with high boron concentration as an etch stop layer was subsequently carried out to achieve better thickness uniformity than that obtained after the spin etching process. The solution for the selective etching process was prepared by diluting NH4OH and H2O2 with de-ionized water. BESOI wafer with excellent surface roughness equivalent to that of a polished Si wafer could be prepared by removing the surface layer of high boron concentration during a chemical mechanical polishing (CMP) process.

Trichostatin A (TSA) is an inhibitor of histone deacetylase. cDNA microarray analysis was used to identify genes modulated by TSA. A total of 93 genes were up-regulated and 27 genes down-regulated. The expressions of some of these genes were confirmed by RT-PCR analysis.

We characterized doxorubicin-induced cell death in gastric cancer cells. It induced apoptotic phenotypes including poly(ADP-ribose) polymerase cleavage, and activation of caspases. By using cDNA microarray analysis, we identified 18 genes that are induced by doxorubicin in at least four of nine gastric cancer cell lines.

Objectives: By utilizing serological analysis of a recombinant cDNA expression library (SEREX), we previously found that autoantibodies to poly (ADP-ribose) polymerase (PARP) are specifically present in the sera of patients with SLE. In this study, recombinant proteins of various domains of PARP were used to determine the PARP domain that is associated with SLE. Methods: We produced four recombinant PARP proteins, which contained various PARP domains, and then carried out enzyme linked immunosorbent assay (ELISA) using these recombinant proteins to identify domains useful for SLE diagnosis. The recombinant proteins used in this analysis were; ADPNF (amino acids 1–234), ET-L2 (amino acids 339–680), ET-L3 (amino acids 681–1014), and ADPCF (amino acids 300–1014). Result: ELISA with ADPNF or ET-L2 showed low sensitivity in the sera of patients with SLE (14.3% and 17.0% respectively), whereas ELISA with ET-L3 or ADPCF showed high sensitivity in the sera of patients with SLE (34.0% and 49.1%, respectively). Autoantibodies to ADPCF were not found in the sera of patients with rheumatoid arthritis (0/30), systemic sclerosis (0/30) or healthy donors (0/54) and were rarely found in polymyositis/dermatomyositis (1/30) and Sjogren syndrome (1/14). Autoantibodies to ADPCF were closely associated with the presence of an oral ulcer in SLE (P=0.03, by the chi-square test). Conclusion: The high sensitivity and specificity shown by autoantibodies to ADPCF protein could be used as a valuable serologic maker for the diagnosis of SLE.

Camptothecin, a topoisomerase I inhibitor, is a well-known anticancer drug. However, its mechanism has not been well studied in human gastric cancer cell lines. Camptothecin induced apoptotic cell death in human gastric cancer cell line AGS. Z-VAD-fmk, pan-caspase inhibitor, blocked apoptotic phenotypes induced by camptothecin suggesting that caspases are involved in camptothecin-induced cell death. An inhibitor of caspase-6 or -8 or -9 did not prevent cell death by camptothecin. Various protease inhibitors failed to prevent camptothecin-induced cell death. These results suggest that only few caspases are involved in camptothecin-induced cell death. Camptothecin induced phosphorylation of ERK1/2, JNK, and p38 MAPK, in a dose and time-dependent manner in AGS. Z-VAD-fmk did not affect MAPK signaling induced by camptothecin suggesting that caspase signaling occurs downstream of MAPK signaling. Blocking of p38 MAPK, but not ERK1/2, resulted in partial inhibition of cell death and PARP cleavage by camptothecin in AGS. Taken together, MAPK signaling is associated with apoptotic cell death by camptothecin.

Systemic sclerosis is a systemic disease that is characterized by tissue fibrosis, small-vessel vasculopathy, and an autoimmune response associated with autoantibodies. We performed serological analysis of cDNA expression library (SEREX) to identify autoantibodies associated with systemic sclerosis. We identified 4 clones that react with sera of patients with SSc but not with those of healthy donors. These clones are phosphoglycerate mutase, centromere autoantigen C, U1 small nuclear ribonucleoprotein, and DNA binding protein B (dbpB). We chose to study autoantibody to DNA binding protein B. Immunoreactivity against recombinant dbpB was detected in 40.5% (15/37) of patients with SSc, 14.6% (6/41) of patents with systemic lupus erythematosus, 6.7% (1/15) of patients with rheumatoid arthritis, 0% (0/12) of patients with Sjogren syndrome, and 5.9% (1/17) of patients with polymyositis/dermatomyositis. The frequency of anti-dbpB was significantly higher in the SSc patients (15/37, 40.5%) compared to the healthy controls (3/41, 7.3%, p=0.0005 by χ2 test). Eleven patients (11/20, 55%) with the diffuse cutaneous type of SSc had anti-dbpB and 4 patients (4/17, 23.5%) with the limited cutaneous type had anti-dbpB. The presence of anti-dbpB was significantly associated with the diffuse cutaneous type (p=0.00003 by χ2 test). This is the first report to suggest that autoantibody to dbpB can be used as a serologic marker of systemic sclerosis.

To identify genes whose alterations lead to gastric cancer, gene expression profiles have been obtained from 22 gastric cancer tissues and their surrounding gastric mucosa tissues. A total of 16 genes were differentially expressed in more than 50% of gastric cancer tissues compared with surrounding gastric mucosa tissues. Genes such as HMG-Y, fibroblast collagenase inhibitor, and osteopontin are among those that are overexpressed in over 50% of the gastric cancer tissues. Dihydrodiol dehydrogenase, ribonuclease A, and glutathione peroxidase are among those genes that are underexpressed in over 50% of the gastric cancer tissues. We identified genes that are associated with clinical phenotypes of patients with gastric cancers. Alpha-II spectrin, Na/K-ATPase and KIAA0111 are those that are enhanced in intestinal type of gastric cancer. Gene such as platelet-endothelial tetraspan antigen 3 was enhanced in highly metastatic gastric cancer tissues.

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the presence of antinuclear antibodies. We performed serological analysis of cDNA expression library (SEREX) to identify autoantibodies associated with SLE. The screening of three different cDNA expression libraries with pooled sera of patients with SLE yielded 11 independent clones that reacted with pooled sera of patients with SLE. In this screening, autoantibodies to poly(ADP-ribose) polymerase (PARP), U1snRNP, and galectin-3 were prevalent in the sera of patients with SLE (26/68, 25/68, 12/63, respectively). The frequency of autoantibody to PARP was significantly higher in SLE than that of healthy donors (0/76) (38.2% vs 0%, p