• Journal of Environmental Science International
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• v.18 no.11
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• pp.1247-1259
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• 2009

We investigated the toxic effects of carbaryl on early embryo development in the African clawed frog, Xenopus laevis. To test the toxic effects, frog embryo teratogenesis assays using Xenopus were performed. Embryos were exposed to various concentrations of carbaryl ($5{\sim}320\;{\mu}M$). $LC_{100}$ for carbaryl was $320\;{\mu}M$, and the $LC_{50}$ determined by probit analysis was the concentration of $235.68\;{\mu}M$. Exposure to $160\;{\mu}M$ of carbaryl resulted in 10 different types of severe external malformations. Histological examination revealed dysplasia of the eyes, heart, guts, somatic muscle, dorsal, liver, blood vessel and swelling of the pronephric ducts. Malformation of neural tissue and brain was not severe even in the high dose of carbaryl. Benzidine blood stain showed distinct inhibition of inducing erythrocytes in embryos and animal cap explants. Electron micrographs of embryo revealed retinal detachment, loose photoreceptor lamella and the degeneration of sarcomeres in the carbaryl-treated group. The mitochondrial degeneration was also observed in the test group.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.27 no.2
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• pp.78-83
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• 2016

Laryngopharyngeal reflux (LPR) disease is an extraoesophageal variant of gastro-esophageal reflux disease that can affect the larynx and pharynx. LPR is associated with symptoms of laryngeal irritation such as throat clearing, coughing, and hoarseness. The main diagnostic methods currently used are laryngoscopy and pH monitoring. The most common laryngoscopic signs are redness and swelling of the throat. However, these findings are not specific of LPR and may be related to other causes or can even be found in healthy individuals. Furthermore, the role of pH monitoring in the diagnosis of LPR is controversial. A therapeutic trial with proton pump inhibitors (PPIs) has been suggested to be cost-effective and useful for the diagnosis of LPR. However, the recommendations of PPI therapy for patients with a suspicion of LPR are based on the results of uncontrolled studies, and high placebo response rates suggest a much more complex and multifactorial pathophysiology of LPR than simple acid reflux. Laryngoscopy and pH monitoring have failed as reliable tests for the diagnosis of LPR. Empirical therapy with PPIs is widely accepted as a diagnostic test and for the treatment of LPR. However, further research is needed to develop a definitive diagnostic test for LPR.

• The Korean Journal of Community Living Science
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• v.20 no.2
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• pp.231-237
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• 2009

This study was conducted to investigate the effects of mugwort powder on two types of flour batters, i.e., medium and cake, using the Falling Number test, RVA test, alveogram, and farimogram. The mugwort powder was added at 3% and 5% on the medium and cake flour bases, respectively. The Falling Numbers of the medium and cake flour batters with mugwort powder were increased due to the alteration of the protein in the flour. Analysis of the RVA characteristics showed that the addition of mugwort powder did not have significant effects on the initial pasting temperature. Peak viscosity, holding strength, final viscosity, and set back values of the medium flour batter were not consistent, but those of the cake flour batter were decreased. The characteristics of the alveogram showed that the addition of mugwort powder increased the extensibility and the swelling index. Farinogram demonstrated that the addition of mugwort powder decreased the water absorption and improved the stability of the medium and cake flour batters.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.145-149
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• 2000

We performed the geotechnical experiments of the hydraulic conductivity and compressive strength test with the stabilized soil in the laboratory, proved that it is useful to use the stabilized soil as an alternative for natural clay soil. Also, for mixing adding materials in the stabilized soil, it was determined that 1) the optimal mixing ratio of cement : bentonite : stabilizing agent was 90:60:1 of mass ratio(kg) for 1㎥ with soil, 2) it was also possible to use low quality bentonite(B\circled2) classified by swelling grade because of little difference from results of the hydraulic conductivity and compressive strength test with high quality bentonite(B\circled1). According to the results of the fixation ability of heavy metals(Pb$^{2+}$, Cu$^{2+}$, Cd$^{2+}$, Zn$^{2+}$) with soil and additives, authors can conclude that the higher pH condition had the more removal efficiency of heavy metals. B\circled1 and cement had especially high removal efficiency of heavy metals in a whole pH because of high alkalinity.alinity.

• Proceedings of the Membrane Society of Korea Conference
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• 2005.11a
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• pp.133-147
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• 2005

In order to investigate applicability for 2,2,2-trifluoroethyl methacrylate (TFEMA) produced by esterification of 2,2,2-trifluoroethanol(TFEA) and methacrylic acid(MA) using pervaporation membrane, poly(vinyl alcohol) (PVA) composite membranes were prepared with glutaraldehyde(GA) onto porous polyethersulfone(PES) support. The degree of crosslinking and thickness of PVA coating layer were analyzed by swelling test and SEM(scanning electron microscopy), respectively. Pervaporation test was done with two feed mixures; TFEA/water, MA/water. The pervaporation data were obtained as a function of content of crosslinking agent, feed composition, and operating temperature, respectively. In case of TFEA-water(90/10 wt%) feed mixture at $80^{\circ}C$, the optimized membrane showed the high permeation flux of 1.5 $kg/m^2hr$ and separation factor of 320. In case of MA-water(90/10 wt%) feed mixture, the membranealso showed high permeation flux of 2.3 $kg/m^2hr$ and separation factor of 740 in same conditions.

• Elastomers and Composites
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• v.54 no.3
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• pp.225-231
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• 2019

Bio-based polyester polyol was synthesized via esterification between azelaic acid and isosorbide. After esterification, bio-based polyurethanes were synthesized using polyester polyol, 1,3-propanediol as the chain extender, and 4,4'-diphenylmethane diisocyanate, in mixing ratios of 1:1:1.5, 1:1:1.8, 1:1:2, and 1:1:2.3. The bio TPU (Thermoplastic Polyurethane) samples were characterized by using FT-IR (Fourier Transform Infrared Spectroscopy), TGA (Thermal Gravimetric Analysis), DSC (Differential Scanning Calorimetry), and GPC (Gel Permeation Chromatography). The mechanical properties (tensile stress and hardness) were obtained by using UTM, a Shore A tester, and a Taber abrasion tester. The viscoelastic properties were tested by an Rubber Processing Analyzer in dynamic strain sweep and dynamic frequency test modes. The chemical resistance was tested with methanol by using the swelling test method. Based on these results, the bio TPU synthesized with the ratio of 1:1:2.3, referred to as TPU 4, showed the highest thermal decomposition temperature, the largest molecular weight, and most compact matrix structure due to the highest ratio of the hard segment in the molecular structure. It also presented the highest tensile strength, the largest elongation, and the best viscoelastic properties among the different bio TPUs synthesized herein.

• Geomechanics and Engineering
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• v.28 no.2
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• pp.157-169
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• 2022

Preloading of soft clays is a common ground stabilization method for improvement of compressibility and the undrained shear strength. The waiting period under preload is a primary design criterion controlling the degree of improvement obtained. Upon unloading the overconsolidation attained with respect to actual loads defines the long term performance. This paper presents a laboratory study for investigation of creep behavior of Famagusta Bay alluvial soft soil preloaded under various effective stresses for analysis of long term performance based on the degree of overconsolidation. Traditional one-dimensional consolidation tests as well as modified creep tests are performed on reconstituted soft specimens. Compressibility parameters are precisely backcalculated using one dimensional consolidation theory and the coefficient of creep is determined using the traditional Cassagrande method as well as two modified methods based on log cycles of time and the inflection of the creep curve. The test results indicated that the long term creep can be successfully predicted considering the proposed method. The creep coefficients derived as part of this method can also be related to the recompression index (recompression index, swelling index) considering the results of the testing method adopted in this study.

• The Academic Congress of Korean Shoulder and Elbow Society
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• 2003.11a
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• pp.51-56
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• 2003

The trained examiner can gain considerable information from visual inspections of the elbow joint, Because much of the joint is subcutaneous, any appreciable alteration in the skeletal anatomy often is detectable. Gross soft tissue swelling or muscle atrophy is also early observed. Inspection and palpation of the medial and lateral epicondyles and the tip of the otecranon from an equilateral triangle with the elbow is flexed. Normally, the arc of flexion extension, although variable, ranges from about O to 140 degrees plus or minus 10 degrees. The posterolateral rotatory instability(PLRI) of the elbow is most common pattern of elbow instability. The lateral collateral ligament complex also includes a narrow but stout band of ligamentous tissue blending with the distal and proterior fibers of the capsule to insert distally on the crista supinatoris of the ulna. This is the lateral ulnar collateral ligament(LUCL). A clinical elbow pivot shift test confirms the PLRI. There are also two active apprehension signs.

• The Journal of the Korean dental association
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• v.9 no.11
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• pp.701-704
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• 1971

The authors have studied histopathologically, based with symptoms, on 51 aged woman who treated in infirmary hospital of dental college of Seoul National University. The results are as follows: 1. Symptoms of patient were swelling of lower left mandible, gingival enlargement, ulceration and severe bleeding. 2. We observed characteristic features on the blood test such as decreased leukocytes with severe decrease of granular leuckocytes and sudden increase of lymphocytes. 3. On the histopathological studies, we observed severe destruction of gingival tissue with few granular leukocytic infiltration, but displaced with massive lymphochtic infiltration.

• Computers and Concrete
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• v.10 no.2
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• pp.173-196
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• 2012

Experimental results of cyclic reversed lateral force test on a two-story reinforced concrete shear wall sub-assemblage are simulated analytically by using the PERFORM-3D program. A comparison of experimental and analytical results leads to the following conclusions: (1) "Shear Wall" and "General Wall" models with "Concrete shear" cannot simulate the pinching phenomena due to shear and show larger amounts of inelastic energy absorption than those in the experiment. (2) Modeling a story-height wall by using two or more "General Wall" elements with "Diagonal shear" in the vertical direction induces the phenomenon of swelling-out at the belly, leading to the erroneous simulation of shear behaviors. In application to tall building structures, it is recommended to use one element of "General Wall" with "Diagonal shear" for the full height of a story. (3) In the plastic hinge area, concrete deformations of analytical models overestimate elongation and underestimate shortening when compared with experimental results.