• Restorative Dentistry and Endodontics
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• v.41 no.2
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• pp.91-97
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• 2016

Objectives: The purpose of this ex vivo study was to compare the antifungal activity of a synthetic peptide consisting of 15 amino acids at the C-terminus of human ${\beta}$-defensin 3 (HBD3-C15) with calcium hydroxide (CH) and Nystatin (Nys) against Candida albicans (C. albicans) biofilm. Materials and Methods: C. albicans were grown on cover glass bottom dishes or human dentin disks for 48 hr, and then treated with HBD3-C15 (0, 12.5, 25, 50, 100, 150, 200, and $300{\mu}g/mL$), CH ($100{\mu}g/mL$), and Nys ($20{\mu}g/mL$) for 7 days at $37^{\circ}C$. On cover glass, live and dead cells in the biomass were measured by the FilmTracer Biofilm viability assay, and observed by confocal laser scanning microscopy (CLSM). On dentin, normal, diminished and ruptured cells were observed by field-emission scanning electron microscopy (FE-SEM). The results were subjected to a two-tailed t-test, a one way analysis variance and a post hoc test at a significance level of p = 0.05. Results: C. albicans survival on dentin was inhibited by HBD3-C15 in a dose-dependent manner. There were fewer aggregations of C. albicans in the groups of Nys and HBD3-C15 (${\geq}100{\mu}g/mL$). CLSM showed C. albicans survival was reduced by HBD3-C15 in a dose dependent manner. Nys and HBD3-C15 (${\geq}100{\mu}g/mL$) showed significant fungicidal activity compared to CH group (p < 0.05). Conclusions: Synthetic HBD3-C15 peptide (${\geq}100{\mu}g/mL$) and Nys exhibited significantly higher antifungal activity than CH against C. albicans by inhibiting cell survival and biofilm.

• Journal of Korean Philosophical Society
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• v.148
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• pp.213-238
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• 2018

The purpose of this paper is to study logical status and meaning of '$l{\grave{e}}i$[類]' in integrated concept system of 'míng[名]'. The subordinate relationships and integrated systems between genus and species are made up 'míng[名]' in pre-Chin's logical arguments. And '$l{\grave{e}}i$[類]' is a concept that designate what kind of category in all names of sorts and kinds in early China. The logical argumentations of early Chinese philosophers reflect subordinate relationship and integrated system of 'míng[名]'. And then early Chinese philosophers use the 'míng[名]' in other to denote a general concept that totally indicate meanings of genus and species like as Confucius' '$zh{\grave{e}}ng$ míng[正名]'. However early Chinese philosophers make philosophical issues of correspondence between míng[名] and shí[實], not subordinate relationships between genus and species. And then they use the 'míng[名]' in other to denotes not a general concept but a kind of category. Therefore the concept of 'míng[名]' used as a meaning of general concept and sorted out integrated concept system of 'míng[名]' as two categories of míng[名] and shí[實] at the same time in logical argumentations of early Chinese philosophers. The '$l{\grave{e}}i$[類]' of pre-Chin difference from genus of Aristotle spontaneously and conceptually. It is not a concept that in other to compose subordinate relationships and integrated systems. It is not a kind of genus. It divide a kind of denotation that means some kind of aggregations into existence and nonexistence. And it divide a kind of connotation that means some kind of attributes into same and difference. When early Chinese philosophers make distinction and demonstration the correspondence between míng[名] and shí[實], so to speak distinction mean to divide and classify into correspondence or non-correspondence, and demonstration mean to argue about the division and classification. Therefore the concept of '$l{\grave{e}}i$[類]' is a criteria that is to divide and classify the correspondence between míng[名] and shí[實] in integrated concept system of 'míng[名]'.

• Journal of Astronomy and Space Sciences
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• v.36 no.1
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• pp.21-33
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• 2019

This paper focuses on the interpretation of radiation fluxes from active galactic nuclei. The advantage of positron annihilation spectroscopy over other methods of spectral diagnostics of active galactic nuclei (therefore AGN) is demonstrated. A relationship between regular and random components in both bolometric and spectral composition of fluxes of quanta and particles generated in AGN is found. We consider their diffuse component separately and also detect radiative feedback after the passage of high-velocity cosmic rays and hard quanta through gas-and-dust aggregates surrounding massive black holes in AGN. The motion of relativistic positrons and electrons in such complex systems produces secondary radiation throughout the whole investigated region of active galactic nuclei in form of cylinder with radius R= 400-1000 pc and height H=200-400 pc, thus causing their visible luminescence across all spectral bands. We obtain radiation and electron energy distribution functions depending on the spatial distribution of the investigated bulk of matter in AGN. Radiation luminescence of the non-central part of AGN is a response to the effects of particles and quanta falling from its center created by atoms, molecules and dust of its diffuse component. The cross-sections for the single-photon annihilation of positrons of different energies with atoms in these active galactic nuclei are determined. For the first time we use the data on the change in chemical composition due to spallation reactions induced by high-energy particles. We establish or define more accurately how the energies of the incident positron, emitted ${\gamma}-quantum$ and recoiling nucleus correlate with the atomic number and weight of the target nucleus. For light elements, we provide detailed tables of all indicated parameters. A new criterion is proposed, based on the use of the ratio of the fluxes of ${\gamma}-quanta$ formed in one- and two-photon annihilation of positrons in a diffuse medium. It is concluded that, as is the case in young supernova remnants, the two-photon annihilation tends to occur in solid-state grains as a result of active loss of kinetic energy of positrons due to ionisation down to thermal energy of free electrons. The single-photon annihilation of positrons manifests itself in the gas component of active galactic nuclei. Such annihilation occurs as interaction between positrons and K-shell electrons; hence, it is suitable for identification of the chemical state of substances comprising the gas component of the investigated media. Specific physical media producing high fluxes of positrons are discussed; it allowed a significant reduction in the number of reaction channels generating positrons. We estimate the brightness distribution in the ${\gamma}-ray$ spectra of the gas-and-dust media through which positron fluxes travel with the energy range similar to that recorded by the Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA) research module. Based on the results of our calculations, we analyse the reasons for such a high power of positrons to penetrate through gas-and-dust aggregates. The energy loss of positrons by ionisation is compared to the production of secondary positrons by high-energy cosmic rays in order to determine the depth of their penetration into gas-and-dust aggregations clustered in active galactic nuclei. The relationship between the energy of ${\gamma}-quanta$ emitted upon the single-photon annihilation and the energy of incident electrons is established. The obtained cross sections for positron interactions with bound electrons of the diffuse component of the non-central, peripheral AGN regions allowed us to obtain new spectroscopic characteristics of the atoms involved in single-photon annihilation.