• Mass Spectrometry Letters
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• v.13 no.3
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• pp.49-57
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• 2022

During electrospray ionization mass spectrometry (ESI-MS) analysis of proteins, the addition of supercharging agents allows for adjusting the maximal charge state, affecting the charge state distribution, and increases the number of ions reaching the detector thus, improving signal detection. We postulate that in di-substituted arene isomers, molecules with higher polarizability values should generate greater interactions and hence elicit higher signal intensities. Polarizability is an electronic parameter which has been demonstrated to predict many chemical interactions. Many properties can be predicted based on charge polarization. Molecular polarizability is a vital descriptor for explaining intermolecular interactions. We employed DFT (density functional/Hartree-Fock hybrid model, B3LYP)-derived descriptors and computed molecular polarizability for ten disubstituted arene reagents, each set made up of three (ortho, meta, para) isomers, with reported use as supercharging reagents during ESI experiments. The atomic electronic inputs were ionization potential (IP), electron affinity (EA), electronegativity (𝛘), hardness (η), chemical potential (µ), and dipole moment (D). We determined that the para isomers showed the highest polarizability values in nine of the ten sets. There was no difference between the ortho and meta isomers. Polarizability also increased with increasing complexity of the substituents on the benzene ring. Polarizability correlated positively with IP, EA, 𝛘, η, and D but correlated negatively with chemical potential. This DFT study predicts that the para isomers of di-substituted arene isomers should elicit the strongest ESI responses. An experimental comparison of the three isomers, especially of larger supercharging molecules, could be carried out to establish this premise.

• Journal of radiological science and technology
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• v.18 no.1
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• pp.81-90
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• 1995

This study was conducted to find out the management status of radioisotopes and radioactive waste products in Korean medical institutions during the period of three years from 1991 to 1993. The results are summarized as follows : 1. The rate of medical institution to the institutions making use of radioisotopes was decreased every year, for example, 18.11 % in the year 1991, 17.86 % in the year 1992 and 15.87 % in the year 1993. 2. The use of domestic made radioisotopes in the medical institution was increased every year, for instance, 89.68 % in the year 1991, 94.21 % in the year 1992 and 99.79 % in the year 1993. 3. 91.01 % of the half life of isotopes used in the medical Institution were two month below. 4. The rate of radioactive waste products in the medical institution to all radioactive waste products was increased every year, for example, 54.44 % in the year 1991, 75.36 % in 1992 and 78.49 % in the year 1993. 5. The rate of inflammable waste products from medical institution was 76.47 % of all inflammable waste products, and 73.99 % of whole waste products was from the medical Institution.

• Journal of radiological science and technology
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• v.7 no.1
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• pp.41-46
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• 1984

Authors investigated an influence of x-ray tube voltage on x-ray quality and dose with using objects of various thickness, and obtained the results as follows: 1. Radiographic effects were influenced by tube voltages and objects. 2. Dose decrement rates hade more influence upon primary-rays than total x-rays at lower tube voltages. 3. The quality of transmitted x-rays was affected by tube voltages and thickness of objects. 4. Scattered-ray contents were proportional to tube voltages with using grid.

• Parasites, Hosts and Diseases
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• v.57 no.4
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• pp.341-357
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• 2019

Acanthamoeba, one of free-living amoebae (FLA), remains a high risk of direct contact with this protozoan parasite which is ubiquitous in nature and man-made environment. This pathogenic FLA can cause sight-threatening amoebic keratitis (AK) and fatal granulomatous amoebic encephalitis (GAE) though these cases may not commonly be reported in our clinical settings. Acanthamoeba has been detected from different environmental sources namely; soil, water, hotspring, swimming pool, air-conditioner, or contact lens storage cases. The identification of Acanthamoeba is based on morphological appearance and molecular techniques using PCR and DNA sequencing for clinico-epidemiological purposes. Recent treatments have long been ineffective against Acanthamoeba cyst, novel anti-Acanthamoeba agents have therefore been extensively investigated. There are efforts to utilize synthetic chemicals, lead compounds from medicinal plant extracts, and animal products to combat Acanthamoeba infection. Applied nanotechnology, an advanced technology, has shown to enhance the anti-Acanthamoeba activity in the encapsulated nanoparticles leading to new therapeutic options. This review attempts to provide an overview of the available data and studies on the occurrence of pathogenic Acanthamoeba among the Association of Southeast Asian Nations (ASEAN) members with the aim of identifying some potential contributing factors such as distribution, demographic profile of the patients, possible source of the parasite, mode of transmission and treatment. Further, this review attempts to provide future direction for prevention and control of the Acanthamoeba infection.

• Journal of radiological science and technology
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• v.8 no.2
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• pp.83-87
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• 1985

There are various kinds of methods to estimate the image quality of x-ray film. The Hawlet-chart is one of the methods to estimate the depiction power of x-ray film image. Authors made a test using the Hawlet-chart in clinical field and demonstrated the superiority of utility value.

• Journal of radiological science and technology
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• v.19 no.1
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• pp.51-54
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• 1996

This study was conducted to find out the indoor radon concentrations from Jan. 1, to Dec. 31, 1995 in Seoul, and the following results were achieved; 1. The average concentration of indoor radon ranged from $0.51pCi/\ell$ to $0.78pCi/\ell$. 2. The correlation coefficients(r) of radon concentration and indoor meteorological conditions were as follows; 1) temperature : r=0.11 2) atmospheric pressure : r= -0.01 3) humidity : r=0.227.

• Journal of radiological science and technology
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• v.8 no.2
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• pp.15-19
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• 1985

The seattered-ray have a bad effect to the image of x-ray film. Therefore, to obtain the better x-ray image, the most important point is to eliminate the scattered-ray, come from the patient, and the easiest method to eliminate the scattered-ray is to use a proper grid for tube voltages. Authors made an experiment on the scattered-ray contents and the image quality in skull radiography, and obtained the results as follows; 1. The scattered-ray content in skull radiography was 83%, but it could be reduced to 35%-50% by using grid. 2. The image contrast was most increased when the using grid ratio was 8:1. 3. The image quality was not influenced by the scattered-ray contents between 32% and 45%.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.678-683
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• 1996

The purpose of this study was to elucidate characteristics of hydrolysates from file-fish flesh with various proteases. File-fish flesh was chopped, homogenized with water, and hydrolysed by 8 different kinds of commercially available protease. High production of peptide was observed in bromelain and neutrase treatment. On the other hand, large amount of free amino acid was observed in esp/sav and pronase treatment. Neutrase and pancreatin hydrolysate contained large amount of 5'-GMP. Organoleptic studies showed that the bromelain, esp/sav and protease hydrolysate had strong bitter taste, while pronase and esp/sav hydrolysate had strong umami taste. From these results, pronase was found to be suitable enzyme for producing file-fish hydrolysate.

• Journal of Korean Physical Therapy Science
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• v.2 no.3
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• pp.691-705
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• 1995

Most of the Medical Junior Colleges faced new environmental changes: School years of some Health-related departments were extended from two-year program to three-year ones; The total high school graduates willing to apply to the colleges will fall short of the legal number limits of this country; Govorment's educational opening policies enables competitive foreign schools to land in our country more easily. In order to survive under these turbulant circumstances, any junior college has to cultivate it's own competitiveness establishing strategies and utilizing resources very efficiently. Some of the major points extracted from three-year junior college professors' opinions against the environmental changes are as follows, 1. Environmental changes should be fully appreciated. And junior colleges have to make haste to establish strategies placing priorities on specific fields which are their own strengths compared to others. 2. The crieria of provisions of miminstry of Education on the facilities and equipments should be enhanced. 3. The practical way to use available resources effectively is to make the best of human resources. 4. It is time to consider consolidating akin departments to one. 5. The school year of the health-related departments should be extended to four years to meet the contemporary needs in the medical fields.

• Journal of radiological science and technology
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• v.9 no.1
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• pp.125-129
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• 1986

We quantified the relationship of fluorescence depends upon the thickness of each absorber by the result of experiment which was practiced to know the relationship of x-ray absorption and photographic effect in the range of diganostic energy about water, acrylic resin, aluminium and copper. There was no great difference in the photographic effect between water and acryl because the absorption degree of the two was mostly equal. But in case of aluminium and copper, it was opposite from the prior. Therefore when we considered the photographic effect in the range of diagnostic energy, it was thought that water and acryl were proper as a absorbers, but not only copper but also aluminium was improper as a absorber.