• Korean Chemical Engineering Research
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• v.55 no.4
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• pp.443-455
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• 2017

This article provides an exclusive overview of the synthesized aragonite precipitated calcium carbonate and its applications in various fields. The last decade has seen a steady increase in the number of publications describing the synthesis, characterization and applications of calcium carbonate morphologies. Mainly, two kinds of processes have been developed for the synthesis of aragonite precipitated calcium carbonate under controlled temperature, concentrations and aging, and the final product is single-phase needle-like aragonite precipitated calcium carbonate formed. This review is mainly focused on the history of developed methods for synthesizing aragonite PCC, crystal growth mechanisms and carbonation kinetics. Carbonation is an economic, simple and ecofriendly process. Aragonite PCC is a new kind of functional filler in the paper and plastic industries, nowadays; aragonite PCC synthesis is the most exciting and important industrial application due to numerous attractive properties. This paper describes the aragonite PCC synthetic approaches and discusses some properties and applications.

• The Korean Journal of Ceramics
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• v.6 no.3
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• pp.286-290
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• 2000

The hydration behavior of fly ash and slag on cement paste were investigated. Early stage of hydration reaction was delayed by mixing fly ash and/or slag with cement, but production of C-S-H hydrates by pozzolanic reaction densified the microstructure. The Ca/Si ratio of C-S-H hydrates in OPC and blended cement of fly ash 50%, slag 50%, fly ash+slag 50% were 2.24, 1.80, 1.82 and 1.97, respectively. The C-S-H gel with low Ca/Si ratio showed rather reticulate than needle-like structure.

• Journal of the Korean Ceramic Society
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• v.28 no.1
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• pp.74-78
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• 1991

Willemite powders which have been prepared by solid state reaction were easy to intermixed impurities, and particle surfaces were demaged in the progress of crushing. The above defacts were easy to accompany non-crystallization for mechanochemical effects and luminescence efficiency was deteriorated. The goal of this study improve each of defacts, and synthesize high purity and fine Mn doped willemite powders by wet and hydrothermal methods without crushing progress. It has been experimentally verified that the single phase Zn1.98Mn0.02SiO4 willemite powders which prepared by hydrothermal synthes is at 220$^{\circ}C$ for 10 hours in 2N KOH solution. The products are like needle and composition is the same with starting composition.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.1
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• pp.6-9
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• 2010

Surface properties of polytetrafluoroethylene(PTFE) films fabricated by rf-magnetron sputtering system with UV surface treatment were investigated to increase water contact angle for their hydrophobic property. We found that the surface morphology and water contact angles of PTFE film modified as a function of the UV treatment times using UV-irradiation were influenced. The water contact angle of PTFE film with optimized UV treatment time for 15 minute showed a high hydrophobicity compared with the film without any surface treatment. We thought that it was due to the energy change of PTFE surface with an adhesion improvement to the glass surface as a smoothing a rough surface with needle-shape and/or the enhancement of an interface property as a removing some defects on the surface like a cleaning effect.

• Journal of Veterinary Clinics
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• v.37 no.1
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• pp.38-41
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• 2020

An 11-year-old castrated male miniature Schnauzer, weighing 8 kg, presented with multiple masses on the humeri. Grossly, the masses were separated from the surrounding soft tissues. Desmoplastic melanoma is an uncommon tumor in dogs. Fine-needle aspiration cytology showed large spindle-shaped cells with a high nuclear-cytoplasmic ratio. Histopathology showed interlacing bundles of fibroblast-like cells, highly pleomorphic multinuclear cells, occasional atypical spindle cells separated by fibrocollagenous stroma, and lymphocyte aggregates admixed with abundant collagen. The tumors were diffusely positive for S100a, a strong marker for desmoplastic melanoma, and negative for desmin. Herein, we report the pathobiology of a rare, uncommon variant of melanoma in a dog.

• Korean Journal of Veterinary Research
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• v.64 no.3
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• pp.25.1-25.5
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• 2024

A 7-year-old castrated male Persian cat presented with a cutaneous mass and an increase in serum amyloid A concentration. Fine needle aspirates of the mass indicated lymphoma, which was also the top differential diagnosis on histopathologic examinations. Immunohistochemically, neoplastic cells tested negative for anti-CD3, PAX5, CD20, and c-Kit, but positive for MUM1, CD79α, and CD138, suggesting extramedullary plasmacytoma. There were tumor-infiltrating non-neoplastic CD3⁺ T and PAX5⁺ B cells. Practitioners should be aware of feline plasmacytoma characterized by lymphoma-like cytologic and histologic features. The present study is valuable in providing the first clinical evidence that proves the immunogenicity of feline plasmacytoma.

• International journal of advanced smart convergence
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• v.13 no.3
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• pp.80-88
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• 2024

Breast cancer remains a significant global health burden, necessitating accurate and timely detection for improved patient outcomes. Machine learning techniques have demonstrated remarkable potential in assisting breast cancer diagnosis by learning complex patterns from multi-modal patient data. This study comprehensively evaluates several popular machine learning models, including logistic regression, decision trees, random forests, support vector machines (SVMs), naive Bayes, k-nearest neighbors (KNN), XGBoost, and ensemble methods for breast cancer prediction using the Wisconsin Breast Cancer Dataset (WBCD). Through rigorous benchmarking across metrics like accuracy, precision, recall, F1-score, and area under the ROC curve (AUC), we identify the naive Bayes classifier as the top-performing model, achieving an accuracy of 0.974, F1-score of 0.979, and highest AUC of 0.988. Other strong performers include logistic regression, random forests, and XGBoost, with AUC values exceeding 0.95. Our findings showcase the significant potential of machine learning, particularly the robust naive Bayes algorithm, to provide highly accurate and reliable breast cancer screening from fine needle aspirate (FNA) samples, ultimately enabling earlier intervention and optimized treatment strategies.

• Journal of radiological science and technology
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• v.33 no.1
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• pp.25-29
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• 2010

To evaluate the usefulness of newly designed percutaneous bone biopsy needle for pumpkin's specimen collection. We manufactured three types of biopsy needle with different internal processing which were made of 10 mm-diameter acrylic material. We made the conventional type (Ct) similar to the clinical type then compared the test group. The type a (Ta) made 1 cm-length internal processing from the distal, type b (Tb) made taper, and type c (Tc) made internal processing like spiral configuration. We performed 20 times biopsy to get an 10 mm length specimen from pumpkin's surface and evaluated the success rate of the biopsy, length of the specimen, and determine internal processing type of the most suitable biopsy needle (ANOVA test). Success rates of Ct, Ta, Tb, and Tc were 55%, 80%, 90%, and 100%, respectively. The lengths of the specimen of Ct, Ta, Tb, and Tc were $5.6{\pm}1.1\;mm$, $5.9{\pm}0.87\;mm$, $3.9{\pm}0.77\;mm$, and $9.4{\pm}0.54\;mm$, respectively. All groups were statistically significant (p < 0.05) except the group between Ct and Ta (p = 0.28). Newly designed bone biopsy needle seems to be useful for obtaining enough specimen. Tc may be more effective than other types.

• Journal of Nutrition and Health
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• v.24 no.3
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• pp.199-205
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• 1991

Retinoic acid. the active metabolite of vitamin A. was detected in the human liver for the first time using a new method. A rapid and sensitive technique has been developed using gradient-elution. reverse-phase high performance liquid chromatography. This assay. with simultaneous multiwavelength detection at 294nm, 325nm and 450nm after saponifcation of liver samples. allows us seperation and quantitation of vitamin E, retinoic acid, total retinoids and various carotenoids in one small sample. The proportion of retinoic acid to total retinoids in human liver appears to be quite $consistent(2.4\pm0.2%$ ). With low vitamin A storage in liver, detection at another wavelenth 354nm would increase the sensitivity for retinoic acid of small quantity This method of analysis could be used for other tissues like red blood cells, plasma or serum, also. Hepatic retinoic acid level with total retinoids and carotenoids would serve a better indicator of functional vitamin A nutriture especially for those with disease requiring needle biopsy of liver.

• Journal of Acupuncture Research
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• v.18 no.3
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• pp.227-238
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• 2001

Objective : There was no report on the treatment of Fascioscapulohumeral (FSH) Muscular Dystrophy by Oriental medicine. But the treatment conducted on the patient admitted to the Sangji Oriental Medicine Hospital from January 9, 2001 to February 23, 2001, a significant treatment result was yielded and would like to suggest treatment plan for the future treatments. Methods : Under the assumption that Korean Bee-Venom Therapy may be affective for treating FSH Muscular Dystrophy, the following points were administered : SI10(노유), SI11(天宗), BL23(腎兪), BL26(關元兪), ST36(足三里), LI4(合谷), Liv3(太衝), SI9(肩貞). CFC(Carthami Flos;紅花 and Cervi Pantotrichum Cornu;鹿茸) herbal extract was treated on the other acupuncture points. Sa-Am(Four needle technique) Acupuncture (tonifying SI5 and ST42, sedating GB41 and ST43) was done every day. For herbal medicine, TaeEumIn ChoWiSeungChung-Tang was given based on the constitutional diagnosis. Results : After 7 weeks of treatment, a remarkable improvement was made for facial muscular movement and muscular strength of the scapular and another regions. Conclusions : 1. Significant improvement in the muscular strength for the case of FSH Muscular Dystrophy was obtained with through Korean Bee-Venom Therapy, Four needle technique, and herbal medication. 2. For progressive muscular dystrophy, it is necessary to practice muscular strength recovery exercise in conjunction with Korean Bee-Venom Therapy. 3. Although this case yielded favorable result, further observation and study must be made to concretely prove the effectiveness of Korean Bee-Venom Therapy for treating muscular dystrophies.