• Corrosion Science and Technology
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• v.21 no.1
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• pp.21-31
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• 2022

Potentiodynamic polarization, EIS measurements, quantum chemical calculations, and molecular dynamic simulations were used to investigate the corrosion behavior of mild steel in 0.5 M aqueous hydrochloric acid medium in the presence or absence of nystatin drug. Potentiodynamic tests suggested that this molecule could act as a mixed inhibitor due to its adsorption on the mild steel surface. The objective of this study was to exploit theoretical calculations to gain a better understanding mechanism of inhibition. Calculating the adsorption behavior of the investigated molecule on Fe (1 1 0) surface was accomplished using Monte Carlo simulation. Molecules were also investigated using Density Functional Theory (DFT), specifically PBE functional, in order to identify the link between molecular structure and corrosion inhibition behavior of the compound under investigation. Adsorption energies between nystatin and iron were estimated more accurately by utilizing Molecular Mechanics calculation with Periodic Boundary Conditions (PBC). Estimated theoretical parameters significantly assisted our understanding of the corrosion inhibition mechanism exhibited by this molecule. They were found to be in accord with experimental results.

• Korean Journal of Clinical Laboratory Science
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• v.48 no.4
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• pp.335-342
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• 2016

Staphylococcus aureus, which is generally susceptible to the involvement route in community, is mostly MSSA. However, CA-MRSA is recently increased. Abuse of antibiotics and glycopeptides may increase VISA and VRSA. This study was conducted to investigate the changes on the antibiotic resistance prevalence and antibiotic susceptibility patterns of Staphylococcus aureus isolated from the wound of patients in a university hospital for the past 10 years. This study showed that antibiotic resistance was higher in males than in females; moreover, the antibiotic resistance rates increased with age. The resistance rate for penicillin, oxacillin, erythromycin, gentamicin, clindamycin, tetracycline, ciprofloxacin, fusidic acid, trimethoprim/sulfamethoxazole, clindamycin, and rifampicin was, respectively, 97.7%, 60.5%, 57.4%, 48.8%, 41.1%, 44.2%, 44.2%, 14.7%, 13.2% and 3.9% in 2006. The resistance rate for penicillin, oxacillin, erythromycin, gentamicin, clindamycin, tetracycline, ciprofloxacin, fusidic acid, trimethoprim/sulfamethoxazole, fusidic acid, clindamycin, and rifampicin was, respectively 95.9%, 62.6%, 55.7%, 28.6%, 50.3%, 34.7%, 38.8%, 34.0%, 2.7% and 8.2% in 2016. Vancomycin, linezolid, quinupristin/dalfopristin, and teicoplanin exhibited 100% in antibiotic susceptibility. In particular, fusidic acid resistance was increased by 19.3% in 2016. Compared with 2006, the decreased point, 12.4% was susceptible and was statistically significant. Therefore, this study suggests that periodic review and understanding of microbial and antibiotic changes should continue to investigate appropriate antibiotic susceptibility.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.9
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• pp.4313-4318
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• 2016

Background: This study documented the performance of providers of visual inspection with acetic acid (VIA) at primary health centers, assessing their compliance with the VIA skills checklist and determinants of non-compliance, and exploring their perceptions of VIA training sessions. Materials and Methods: A cross-sectional study was conducted among VIA providers in the $Mekn\grave{e}s$-Tafilalet region of Morocco. Structured observation of their performance was conducted through supervisory visits and multiple focus group discussions (FGDs). Results: Performance of all the recommended steps for effective communication was observed in a low proportion of procedures (36.4%). Midwives/nurses had higher compliance than general practitioners (GPs) (p<0.001). All recommended steps for VIA examination were performed for a high proportion of procedures (82.5%). Compliance was higher among midwives/nurses than among GPs (p<0.001) and among providers in rural areas than those in urban areas (p<0.001). For pre-VIA counselling, all recommended steps were performed for only 36.8% of procedures. For post-VIA counseling, all recommended steps were performed in a high proportion (85.5% for VIA-negative and 85.1% for VIA-positive women). Midwives/nurses had higher compliance than GPs when advising VIA-positive women (p=0.009). All infection prevention practices were followed for only 14.2% of procedures, and compliance was higher among providers in rural areas than those in urban areas (p<0.001). Most FGD participants were satisfied with the content of VIA training sessions. However, they suggested periodic refresher training and supportive supervision. Conclusions: Quality assurance of a cervical cancer screening program is a key element to ensure that the providers perform VIA correctly and confidently.

• Journal of Life Science
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• v.11 no.6
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• pp.595-602
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• 2001

The prelectin histochemical methods had been applied to study mucosubstances properties of esophageal mucous cells in four teleostean species, i, e.. sebastes schlegli, Halichoeres poecilopterus, Bryzoichtys lysimus and Takifugu pardalis. The following methods were used: periodic acid Scheff"s(PAS) reaction, alcian blue(AD) pH 2.5, AB pH 1.0, AB pH 2.5-PAS, aldehyde fuchsin (AF) pH 1.7-AB pH 2.5 and high iron diamine (HID)-AD pH 2.5 stainings. The number size and shape of esophasgeal mucous cells studied depend on the fish species. Esophageal mucous cells of Sebastes schlegli and Halichoeres poecilopterus were mixed with large, medium sized and small mucous cells, but these cells of the species were mixed with medium sized and small mucous cells. The large esophageal with moderate to considerable amount of acid mucin. Most of the large mucous cells in these species contained neutral mucin and strongly sulfomucin, whereas a few mucous cells contained neutral mucin, strongly sulfomucin, and sialomucin. Medium sized and small mucous cells of these species contained considerable to large amount of neutral mucin, and small to considerable amount of acid mucin, Most of the medium sized and small mucous cells contained neutral mucin and sialomucin, but a few mucous cells contained neutral mucin and strongly sulfomucin or neutral combined with strongly sulfomucin and sialomucin. Most of the esophageal mucous cells pf Bryzoichthys lysimus contained small amount of neutral mucin, while on the other hand a feww mucous cells contained small amount of neutral mucin and minimal amount of sialomucin. But the esophageal mucous cells of Takifugu pardalis contained considerable amount of neutral mucin only.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.3
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• pp.310-321
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• 2019

Objectives: The purpose of this study was to investigate types and characteristics of chemical substances used in LCD(Liquid crystal display) panel manufacturing process. Methods: The LCD panel manufacturing process is divided into the fabrication(fab) process and module process. The use of chemical substances by process was investigated at four fab processes and two module processes at two domestic TFT-LCD(Thin film transistor-Liquid crystal display) panel manufacturing sites. Results: LCD panels are manufactured through various unit processes such as sputtering, chemical vapor deposition(CVD), etching, and photolithography, and a range of chemicals are used in each process. Metal target materials including copper, aluminum, and indium tin oxide are used in the sputtering process, and gaseous materials such as phosphine, silane, and chlorine are used in CVD and dry etching processes. Inorganic acids such as hydrofluoric acid, nitric acid and sulfuric acid are used in wet etching process, and photoresist and developer are used in photolithography process. Chemical substances for the alignment of liquid crystal, such as polyimides, liquid crystals, and sealants are used in a liquid crystal process. Adhesives and hardeners for adhesion of driver IC and printed circuit board(PCB) to the LCD panel are used in the module process. Conclusions: LCD panels are produced through dozens of unit processes using various types of chemical substances in clean room facilities. Hazardous substances such as organic solvents, reactive gases, irritants, and toxic substances are used in the manufacturing processes, but periodic workplace monitoring applies only to certain chemical substances by law. Therefore, efforts should be made to minimize worker exposure to chemical substances used in LCD panel manufacturing process.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.454-454
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• 2014

Silicon microwire array is one of the promising platforms as a means for developing highly efficient solar cells thanks to the enhanced light trapping efficiency. Among the various fabrication methods of microstructures, deep reactive ion etching (DRIE) process has been extensively used in fabrication of high aspect ratio microwire arrays. In this presentation, we show precisely controlled Si microwire arrays by tuning the DRIE process conditions. A periodic microdisk arrays were patterned on 4-inch Si wafer (p-type, $1{\sim}10{\Omega}cm$) using photolithography. After developing the pattern, 150-nm-thick Al was deposited and lifted-off to leave Al microdisk arrays on the starting Si wafer. Periodic Al microdisk arrays (diameter of $2{\mu}m$ and periodic distance of $2{\mu}m$) were used as an etch mask. A DRIE process (Tegal 200) is used for anisotropic deep silicon etching at room temperature. During the process, $SF_6$ and $C_4F_8$ gases were used for the etching and surface passivation, respectively. The length and shape of microwire arrays were controlled by etching time and $SF_6/C_4F_8$ ratio. By adjusting $SF_6/C_4F_8$ gas ratio, the shape of Si microwire can be controlled, resulting in the formation of tapered or vertical microwires. After DRIE process, the residual polymer and etching damage on the surface of the microwires were removed using piranha solution ($H_2SO_4:H_2O_2=4:1$) followed by thermal oxidation ($900^{\circ}C$, 40 min). The oxide layer formed through the thermal oxidation was etched by diluted hydrofluoric acid (1 wt% HF). The surface morphology of a Si microwire arrays was characterized by field-emission scanning electron microscopy (FE-SEM, Hitachi S-4800). Optical reflection measurements were performed over 300~1100 nm wavelengths using a UV-Vis/NIR spectrophotometer (Cary 5000, Agilent) in which a 60 mm integrating sphere (Labsphere) is equipped to account for total light (diffuse and specular) reflected from the samples. The total reflection by the microwire arrays sample was reduced from 20 % to 10 % of the incident light over the visible region when the length of the microwire was increased from $10{\mu}m$ to $30{\mu}m$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.2
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• pp.318-323
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• 2004

This study has been carried out to investigate the effect of the beverage contained Radix puerariae (15%) and Bambusae caules in Liquamen Phyllostachyos (1%) on the alcohol administered mouse. The control group was treated with alcohol (40% alcohol, 8.0 mL/kg of body weight), experimental group 1 (Exp.1) was administered with beverage (8.0 mL/kg of body weight) before alcohol treatment, and experimental group 2 (Exp.2) was administered with beverage after alcohol treatment. Blood alcohol concentrations were decreased by 11% (in Exp. 1) and 17% (in Exp. 2) compared with control group. The concentrations of serum aspartate aminotransferase (AST) were slightly increased in Exp. 1 and Exp.2, but alanine aminotransferase (ALT) levels were not changed compared with control group. Mn-Superoxide dismutase activity was increased by about 70% in the experimental groups in comparison to control group. The Exp. 1 and Exp. 2 contained more periodic-acid Schiff (PAS)-positive materials than the control group. Electron microscopical observations showed that, cell organelles of hepatocytes were more disoriented in the control group than in Exp. 1 and Exp. 2. These results suggest that the beverage contained Radix puerariae and Bambusae caules in Liquamen Fhyllostachyos is a safe and effective therapeutic agent for alcohol abuse.

• Biomedical Science Letters
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• v.4 no.2
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• pp.77-86
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• 1998

Age-related changes in the lens capsule and epithelium of cataractous patients, ranging from 20 to 7o years old, were studied by means or LM, immunohistochemistry, and TEM. The lens capsule was divided into four zones; the anterior, subanterior, middle, and basal zone. The van Gieson staining reaction for collagen was prominent at the anterior and subanterior parts of the lens capsule. The reaction was more decreased in the elder group than the younger group. The collagen type IV reaction was prominent at the anterior zone of the lens capsule and around the cell. The reaction was more decreased in the elder group than the younger group. 3. The Periodic Acid Shiff-Alcian Blue reaction for mucopolysaccharide was prominent at the anterior zone of the lens capsule. The reaction was more decreased in the elder group than the younger group. The Apoptotic reaction was prominent at the nucleus of the lens epithelial cell. In the elder the cataractous group, the number of the apoptotic cells was more decreased. The electron microscopic change of lens epithelial cells were characterized by the increase of lateral fold and the cytoplasm with various vacuoles and Golgi complex. In the basal part, lens epithelial cell protruded toward the lens capsule in the 20-year-old group. The basal part of the 40-year-old group was flattened and covered with the cytoplasmic processes of adjacent cells. In the 60-year-old group, the mass of rough filaments separated lens capsule and the basal part of the lens epithelial cell. The electron microscopic change of the middle part of lens capsule was characterized by the aggregation of electron dense materials in the 40-year-old group, and the appearance of filamentous materials and the decrease of electron dense granules in the 60-year-old group.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.15 no.3
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• pp.165-170
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• 2015

Ornithine transcarbamylase (OTC) deficiency is a rare X-linked genetic disorder of urea synthesis in newborns. It is the most common urea cycle disorder and leads to elevated levels of ammonia in the blood. Excessive ammonia can cause various symptoms, including vomiting, lethargy, and coma. Boys have a more serious form of OTC deficiency than girls. If not treated immediately, severe OTC deficiency can lead to neurologic abnormalities, hyperammonemic coma, and death. Because late-onset OTC deficiency, which is more common in girls, presents mild symptoms, it is easy to miss diagnosis and prompt treatment. We describe an 11-month-old girl who presented periodic vomiting, intermittent lethargy, and seizure. She was diagnosed with OTC deficiency by elevated serum ammonia and urine orotic acid levels. Genetic analysis of the OTC gene revealed a missense mutation in exon 5 (c.418G>C). We reported an experience of exact diagnosis and successful treatment of late-onset OTC deficiency in our patient.

• The Korean Journal of Zoology
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• v.19 no.1
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• pp.25-32
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• 1976

To observe the changes of mucosubstances of the mucous secreting cells, stomach tissues in frog tadpoles at each stage of metamorphosis were fixed in 10% buffered formalin at $4^{\circ}C$, embedded in paraffin, sectioned to 4 $\mu$m thickness and stained with periodic acid-Schiff(PAS) and alcian blue (AB) of pH 2.5 and pH 1.0. The results obtained were as follows: 1. The reactivities of the surface mucous cells, which exhibited strong PAS-positivity and weak alcianophilia at both pH 2.5 and 1.0, were not changed in metamorphosis stages and the intracellular contents of neutral mucosubstances in the surface mucous cells increased significantly in XXIV and XXV stages of metamorphosis. 2. In the foveolar mucous cells, which appear after metamorphosis XXI, the staining reactivities to PAS, AB of pH 2.5 and 1.0 were the same as that of surface mucous cells during metamorphosis and the alcianophilia were stronger at pH 1.0 than at pH 2.5. 3. THe mucous neck cells, which appear after metamorphosis XXIV, exhibited a strong PAS-positive reaction and weak alcianophilia at metamorphosis XXIV but at metamorphosis XXV weak reactivity to PAS and strong alcianophilia at pH 1.0.