• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.271-274
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• 2001

최근 압전성 및 유전성, 비선형 광학전도성 등과 같은 특성을 갖는 전기전자 및 광기능성 고분자에 대한 연구가 많이 이루어지고 있다[1-2]. 그 중에서 압전 및 초전성을 나타내는 대표적 유기 고분자인 poly(vinylidene fluoride)(PVDF)의 경우 압전성을 향상시키기 위하여 vinylidene. fluoride(VDF)나 vinyl fluoride(VF), trifluoroethylene(TrFE) 등과 공중합시킨 고분자들에 대한 연구가 활발히 진행되어 왔다[3-4]. (중략)

• Journal of Oral Medicine and Pain
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• v.49 no.1
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• pp.12-17
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• 2024

Dry mouth is common among older adults and significantly affects the oral health-related quality of life. It is a significant risk factor for dental caries, particularly root caries, in older adults due to concurrent periodontal disease and age-related comorbidities. Clinicians managing patients with dry mouth must be aware of preventive measures against dental caries. This clinical review aims to update our knowledge on the use of fluoride for caries prevention in order to establish better strategies for the management of dry mouth in older adults.

• International Journal of Industrial Entomology and Biomaterials
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• v.15 no.1
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• pp.59-68
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• 2007

Changes in protein metabolism were studied in hemolymph and fat body on days 1, 3, 5 and 7 of the fifth-instar silkworm, Bombyx mori, exposed to lethal, sublethal doses and prevailing levels of fluoride in groundwater in Karnataka and Andhra Pradesh States of India. The total protein content indicated a depletion followed by a concomitant increase in accumulation of free amino acids. Concurrently, the activity of protease in both of the tissues was also increased. A steady enhancement in the activities of alanine aminotransferase and aspartate aminotransferase paralleled the elevation of glutamate dehydrogenase activity in the tissues studied. It is presumed, on the basis of these results, that the fluoride toxicity causes major changes in protein metabolism of the silkworms.

• YAKHAK HOEJI
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• v.57 no.5
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• pp.376-381
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• 2013

The present study was undertaken to investigate the influence of curcumin on vascular smooth muscle contractility and to determine the mechanism involved. We hypothesized that curcumin, the primary ingredient of Curcuma longa, plays a role in vascular relaxation through inhibition of Rho-kinase in rat aortae. Denuded arterial rings from male Sprague-Dawley rats were used and isometric tensions were recorded using a computerized data acquisition system. Interestingly, curcumin inhibited fluoride-induced contraction but didn't inhibit phorbol ester-induced contraction suggesting that additional pathways different from endothelial nitric oxide synthesis might be involved in the vasorelaxation. Furthermore, curcumin significantly inhibited fluoride-induced increases in pMYPT1 levels. On the other hand, it didn't significantly inhibit phorbol ester-induced increases in pERK1/2 levels suggesting the mechanism involving inhibition of fluoride-induced MYPT1 phosphorylation. This study provides evidence that curcumin induces vascular relaxation through inhibition of Rho-kinase in rat aortae.

• International journal of advanced smart convergence
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• v.2 no.2
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• pp.16-18
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• 2013

In this paper, we develop a method to design a flexible thin film audio systems utilizing Polyvinylidene fluoride. The system we designed showed the properties of increased transparency and sound pressure levels. As an input terminal transparent oxide thin film is adopted. In order to provide dielectric insulation, a transparent insulating oxide thin film is coated to obtain double -layered structure. In the range of visible light, the output from the output of the system showed an increased and improved sound pressure level. The piezoelectric polymer film of polyvinylidene fluoride (PVDF) is used to produce mechanical vibration due to the applied electrical voltage signal. An analog electric voltage signal is transformed into sound waves in the audio system.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.3 no.2
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• pp.116-121
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• 2017

To overcome the low reactivity and solubility of alkali metal fluorides (MFs), various types of phase transfer catalysts (PTCs) have been developed over the last decades. However, since the fluoride activated by such PTC sometimes has a strong basicity, it may cause various side reactions such as elimination reaction or hydroxylation reaction in the nucleophilic fluorination reaction. Also, they may cause separation problems in the compound purification process. In recent advanced study, various PTCs have been developed to solve these problem of conventional catalyst. In this review, we would like to introduce three kinds of novel multifunctional organic catalysts such as bis-tert-alcohol-functionalized crown-6-calix[4]arene (BACCA), easy separable pyrene-tagged ionic liquid (PIL) by reduced graphene oxide (rGO), and tri-tert-butanolamine organic catalyst.

• The Journal of the Korean dental association
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• v.50 no.9
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• pp.552-557
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• 2012

Bamboo salt is a special processed salt by Korean traditional recipe. Recent study results showed that bamboo salt or bamboo salt with some other materials like herbal extracts have the anti-microbial activity, inhibition effects of dental plaque and gingival inflammation. Bamboo salt also showed anti-cariogenic effects; remineralization and acid resistance. Compare to fluoride toothpaste, bomboo salt toothpaste with fluoride showed the more effective remineralization on inner part of the early dental caries lesion. It increased the surface hardness and decreased lesion depth of early dental caries lesion. Thus, it is suggested thai bamboo salt could be used as a anti-microbial, anti-plaque, anti-inflammatory and anti-cariogenic material for oral disease prevention. Especially, bamboo salt dentifrice with fluoride can be recommanded as a useful remineralizing agent.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.392.2-392.2
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• 2014

Poly (vinylidene fluoride) thin films were deposited by a spray-coating technology. Two organic solvents with different boiling point were used to prepare the mixture solution for spray coating process: N-Methylpyrrolodone ($B.P.=202^{\circ}C$); Tetrahydrofuran ($B.P.=66^{\circ}C$). Post-deposition annealing temperature was varied for the spray-coated Poly(vinylidene fluoride) thin films. Structural characteristics of the thin films were comparatively investigated by FT-IR and XRD in relation with the organic solvent and post-deposition annealing temperature.

• The Journal of the Korean dental association
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• v.12 no.3
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• pp.155-158
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• 1974

Catecholamine levels were determined in the submandibular glands of new born rats treated with physiologieal saline solution or large doses of sodium fluoride (10mg/kg) for verying periods of time. In control group, catecholamine levels were gradually increased from fifth day of life until twenty-fifth day of life. When fluoride treatment was started on the fifth day after birth and continued daily to the thirty-fifthday of life, decreased catecholamine levels were obsrved on the fifth, through all experiments, and thirth-fifth day. Daily fluoride treatment from the fifteenth through the thirty-fifth day after birth induced the decreased catecholamine levels which were higher than the levels in submandibular glands of rats treated from the fifth day to the thirty-fifth day after birth with NaF. These experiments suggest that fluoride may be affecting catecholamine biosynthetic mechanisms which were duveloping during the fifteenth to twenty-fifth day of life.

• Journal of the Korean Wood Science and Technology
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• v.36 no.2
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• pp.73-78
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• 2008

Inorganic chemical treated wood was prepared by impregnation of calcium or magnesium chloride ($CaCl_2$ or $MgCl_2$) solution and immersion in saturated solution of ammonium fluoride ($NH_4F$) as a reactant in order to make an introduction of a refractory fluorides with fungicidal and insecticidal effects in wood. The weight percent gains (WPGs) were increased with increase in concentration of calcium chloride or magnesium chloride solution, and were higher in treatment with calcium chloride than with magnesium chloride. Inorganic substances were produced mainly in the lumina of tracheides. These substances were proved to be the calcium fluoride or magnesium fluoride by the energy dispersive X-ray analyzer in conjunction with a scanning electron microscope (SEM-EDX). The treated wood showed good decay resistance because the weight losses were hardly occurred by the test fungi such as Tyromyces palustris and Trametes versicolor. The fire resistance effect was superior to the treated wood compared with that of the untreated wood.