• Korean Journal of Materials Research
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• v.30 no.3
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• pp.117-122
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• 2020

The effects of fast neutron irradiation on the electrical and optical properties of Li (3 at%) doped ZnSnO (ZTO) thin films fabricated using a sol-gel process are investigated. From the results of Li-ZTO TFT characteristics according to change of neutron irradiation time, the saturation mobility is found to increase and threshold voltage values shift to a negative direction from 1,000 s neutron irradiation time. X-ray photoelectron spectroscopy analysis of the O 1s core level shows that the relative area of oxygen vacancies is almost unchanged with different irradiation times. From the results of band alignment, it is confirmed that, due to the increase of electron carrier concentration, the Fermi level (E_F) of the sample irradiated for 1,000 s is located at the position closest to the conduction band minimum. The increase in electron concentration is considered by looking at the shallow band edge state under the conduction band edge formed by fast neutron irradiation of more than 1,000 s.

• Safety and Health at Work
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• v.4 no.2
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• pp.87-94
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• 2013

Background: In times of continuous change and volatile markets, organizations are increasingly characterized by downsizing, work intensification, and resource rationalization. This has resulted in diversification, and the emergence of newrisks within the field of occupational health and safety, with an important impact. This paper focuses on one such type of risk in the modern workplace-psychosocial risks. The current study aimed to explore stakeholder perspectives, regarding the extent to which psychosocial risks are incorporated into strategic risk management practices, at both the business and policy level. Methods: Semi-structured interviews were conducted with 14 professionals, representing employer, expert, policy maker, and trade union stakeholder perspectives. Results: It was found that the majority of organizations do not sufficiently, if at all, understand and incorporate psychosocial risks into strategic decision making, whereby the key barrier related to practical difficulties of not knowing how to manage psychosocial risks adequately. Conclusion: The study found that there is a need to close the gap between policy and practice on a number of levels. Future recommendations comprise a policy framework and infrastructure underpinned by educational initiatives, partnerships, and networks to drive a shift in attitudes toward recognizing the duality of the concept of risk (including both potential negative and positive outcomes) and moving beyond simple regulatory compliance.

• Journal of the Korean Chemical Society
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• v.37 no.8
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• pp.753-756
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• 1993

Studies on the molecular interactions of dimethylsulfoxide (DMSO) with water and/or some alkanols were carried out by vapor pressure osmometry at 40$^{\circ}C$. Negative deviation from Raoult's law was observed for the DMSO-water, methanol, ethanol, 1-propanol, 2-propanol, and 2-methyl-1-propanol systems, whereas positive deviation from Raoult's law was observed for the DMSO-1-butanol and 1-pentanol systems. The results were interpreted in terms of molecular interactions between unlike molecules, and of self-association of DMSO molecules, respectively. Measured chemical shift of hydroxyl proton of the solvents also supported the results.

• Journal of Microbiology and Biotechnology
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• v.26 no.11
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• pp.1972-1982
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• 2016

Influenza A virus is a single-stranded RNA virus with a genome of negative polarity. Owing to the antigenic diversity and cross concrete shift, an immense number of novel strains have developed astronomically over the years. The present work deals with the codon utilization partialness among five different influenza A viruses isolated from human hosts. All the subtypes showed the homogeneous pattern of nucleotide utilization with a little variation in their utilization frequencies. A lower bias in codon utilization was observed in all the subtypes as reflected by higher magnitudes of an efficacious number of codons. Dinucleotide analysis showed very low CpG utilization and a high predilection of A/T-ending codons. The H5N1 subtype showed noticeable deviation from the rest. Codon pair context analysis showed remarkable depletion of NNC-GNN and NNT-ANN contexts. The findings alluded towards GC-compositional partialness playing a vital role, which is reflected in the consequential positive correlation between the GC contents at different codon positions. Untangling the codon utilization profile would significantly contribute to identifying novel drug targets that will pacify the search for antivirals against this virus.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.10
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• pp.621-628
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• 2020

The study investigates a promising sustainable crop-insurance risk mitigation plan, namely, Group Risk Income Protection (GRIP) insurance, for the cultivation of Para rubber, a crop for which Southern Thailand constitutes over half of the national harvested area, but which recently experienced a shift in prices and yields, substantially affecting farmers. The research takes as its starting point historical data covering the 2001-2018 period for this crop's cultivation in three of Thailand's Andaman South Coast provinces - Trang, Krabi, and Phangnga. The results indicate that, from a relatively high base in 2001, Trang's yields dropped sharply before a more gradual decline (apparently still ongoing), whereas those for Krabi and Phangnga followed a smoother downward trajectory throughout the period. Meanwhile, prices everywhere rose steadily before falling from 2011 onwards - a decrease that shows no signs of abating. The yield/price relationship was negative for one province and slightly positive for the other provinces. Furthermore, all provinces' Para rubber income initially grew continually but fell after 2011, with this trend seemingly persisting to this day. The paper's findings suggest that, after early moves to entrench GRIP insurance, it looks set to become a feasible option for Para rubber, making policy agreement details an interesting subject for subsequent investigations.

• Journal of Electrochemical Science and Technology
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• v.7 no.4
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• pp.269-276
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• 2016

Carbon-supported ordered Pt-Ti alloy nanoparticles were prepared as a durable and efficient oxygen reduction reaction (ORR) electrocatalyst for polymer electrolyte membrane fuel cells (PEMFCs) via wet chemical reduction of Pt and Ti precursors with heat treatment at $800^{\circ}C$. X-ray diffraction analysis confirmed that the prepared electrocatalysts with Ti precursor molar compositions of 40% (PtTi40) and 25% (PtTi25) had ordered $Pt_3Ti$ and $Pt_8Ti$ structures, respectively. Comparison of the ORR polarization before and after 1500 electrochemical cycles between 0.6 and 1.1 V showed little change in the ORR polarization curve of the electrocatalysts, demonstrating the high stability of the PtTi40 and PtTi25 alloys. Under the same conditions, commercial carbon-supported Pt nanoparticle electrocatalysts exhibited a negative potential shift (10 mV) in the ORR polarization curve after electrochemical cycling, indicating degradation of the ORR activity.

• Bulletin of the Korean Chemical Society
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• v.28 no.2
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• pp.263-270
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• 2007

New mono- and bis-Cu(II)-triazacyclononane(tacn) complex that conjugated with 9-aminoacridine were synthesized, and their binding modes and DNA cleavage activity were investigated in this study. When the classic intercalator, 9-aminoacridine, was conjugated to mono- and bis-Cu(II)-tacn complexes, a significant red-shift and hypochromism in absorption spectrum was apparent in the acridine absorption region upon binding to DNA. Furthermore, the magnitude of the negative reduced linear dichroism signal in the substrate absorption region appeared to be larger than that in the DNA absorption region. These spectral observations indicated that the acridine moiety intercalated when the Cu(II)-tacn complex was conjugated. In contrast, from a close analysis of the circular and linear dichroism spectrum, the aminoacridine-free bis-Cu(II)-tacn complex was concluded to bind at the phosphate groups of DNA. The 9-aminoacridine-free-bis-Cu(II)-tacn complex produces the nicked and linear DNA. On the other hand, 9-aminoacridine conjugated mono-and bis-Cu(II)-tacn complexes showed unspecific binding with negligible DNA cleavage.

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.188-196
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• 2013

We have investigated the effects of formalin on the assembly of colloidal gold nanoparticles (AuNPs) prepared by laser ablation of a solid gold target in deionized water. Upon addition of formalin, the surface plasmon resonance (SPR) band at 519 nm for pure AuNPs decreases and shifts to red while a new broad SPR band appears at ~700 nm. The red-shift is prominent with increase in the incubation time. The average size of the initial AuNPs is around 12 nm but it increases to 23 nm after addition of formalin. It turns out that formalin acts as a cationic surfactant for AuNPs with negative surface charge in the colloidal solutions. Furthermore, through analysis of the Raman spectrum of formalin and the density functional theory calculations, we confirm that methanediol is the main species in formalin which is in charge of the aggregation of AuNPs.

• Molecules and Cells
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• v.38 no.2
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• pp.171-179
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• 2015

Prostatic acid phosphatase (PAP) expression increases proportionally with prostate cancer progression, making it useful in prognosticating intermediate to high-risk prostate cancers. A novel ligand that can specifically bind to PAP would be very helpful for guiding prostate cancer therapy. RNA aptamers bind to target molecules with high specificity and have key advantages such as low immunogenicity and easy synthesis. Here, human PAP-specific aptamers were screened from a 2'-fluoropyrimidine (FY)-modified RNA library by SELEX. The candidate aptamer families were identified within six rounds followed by analysis of their sequences and PAP-specific binding. A gel shift assay was used to identify PAP binding aptamers and the 6N aptamer specifically bound to PAP with a Kd value of 118 nM. RT-PCR and fluorescence labeling analyses revealed that the 6N aptamer bound to PAP-positive mammalian cells, such as PC-3 and LNCaP. IMR-90 negative control cells did not bind the 6N aptamer. Systematic minimization analyses revealed that 50 nucleotide sequences and their two hairpin structures in the 6N 2'-FY RNA aptamer were equally important for PAP binding. Renewed interest in PAP combined with the versatility of RNA aptamers, including conjugation of anti-cancer drugs and nano-imaging probes, could open up a new route for early theragnosis of prostate cancer.

• Journal of Microbiology
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• v.42 no.2
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• pp.69-73
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• 2004

Vibrio vulnificus, a Gram-negative bacterium found in estuarine waters, is responsible for over 95％ of all seafood-related deaths in the United States. As a result of a temperature downshift to 5$^{\circ}C$, this organism enters the viable but nonculturable (VBNC) state. Changes in the membrane fatty acid (FA) composition of V. vulnificus may be a contributing factor to the ability of this organism to enter into and survive in the VBNC state. This hypothesis was tested by incubating the organism at 5$^{\circ}C$ in arti-ficial sea water and analyzing the cells' FAs during the initial hours of temperature and nutrient down-shift. Prior to downshift, the predominant FAs were 16:0, 16:1 and 18:0. During the first four hours of downshift, statistically significant changes occurred in 15:0, 16:1, 16:0, 17:0, and 18:0. These results indicate that changes in FA composition occur prior to entry of V. vulnificus into the VBNC state, suggesting that the ability to maintain membrane fluidity may be a factor in this physiological response. Cells in which fatty acid synthesis was inhibited did not survive, indicating that active fatty acid metab-olism is essential for entry of cells into the VBNC state.