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Transport Paths of Surface Sediment on the Tidal Flat of Garolim Bay, West Coast of Korea (황해 가로림만 조간대 표층퇴적물의 이동경로)

  • Shin, Dong-Hyeok;Yi, Hi-Il;Han, Sang-Joon;Oh, Jae-Kyung;Kwon, Su-Jae
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.3 no.2
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    • pp.59-70
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    • 1998
  • Two-dimensional trend-vector model of sediment transport is first tested in the tidal flat of Garolim Bay, mid-western coast of the Korean Peninsula. Three major parameters of surface sediment, i.e., mean grain size, sorting and skewness, are used for defining the best-fitting transport trend-vector on the sand ridge and muddy sand flat. These trend vectors are compared with the real transport directions determined from morphology, field observation and bedforms. The 15 possible cases of trend vectors are calculated from total sediments. In order to find the role of coarse sediments, trend vectors from sediments coarser than < 4.5 ${\phi}$, (sand size) are separately calculated from those of total sediments. As compared with the real directions, the best-fitting transport-vector model is the "case M" of coarse sediments which is the combined trend vectors of two cases: (1) finer, better sorted and more negatively skewed and (2) coarser, better sorted and more positively skewed. This indicates sand-size grains are formed by simpler hydrodynamic processes than total sediments. Transported sediment grains are better sorted than the source sediment grains. This indicates that consistent hydrodynamic energy can make sediment grains better sorted, regardless of complicated mechanisms of sediment transport. Consequently, both transported vector model and real transported direction show that the source of sediments are located outside of bay (offshore Yellow Sea) and in the baymouth. These source sediments are transported through the East Main Tidal Channel adjacent the baymouth. Some are transported from the subtidal zone to the upper tidal flat, but others are transported farther to the south, reaching the south tidal channel in the study area. Also, coarse sediment grains on the sand ridge are originally from the baymouth, and transported through the subtidal zone to the south tidal channel. These coarse sediments are moved to the northeast, but could not pass the small north tidal channel. It is interpreted that the great amount of coarse sediments is returned back to the outside of the bay (Yellow Sea) again through the baymouth during the ebb tide. The distribution of muddy sand in the northeastern part of study area may result from the mixing of two sediment transport mechanisms, i.e., suspension and bedload processes. The landward movement of sand ridge and the formation of the north tidal channel are formed either by the supply of coarse sediments originating from the baymouth and outside of the bay (subaqueous sand ridges including Jang-An-Tae) or by the recent relative sea-level rise.

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Diagnostic Value of Serum Procalcitonin in Febrile Infants Under 6 Months of Age for the Detection of Bacterial Infections (발열이 있는 6개월 미만의 영아에서 세균성 감염에 대한 procalcitonin의 진단적 가치)

  • Kim, Nam Hyo;Kim, Ji Hee;Lee, Taek Jin
    • Pediatric Infection and Vaccine
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    • v.16 no.2
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    • pp.142-149
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    • 2009
  • Purpose : The aim of this study was to determine the diagnostic value of serum procalcitonin (PCT) compared with that of C-reactive protein (CRP) and the total white blood cell count (WBC) in predicting bacterial infections in febrile infants<6 months of age. Methods : A prospective study was performed with infants <6 months of age who were admitted to the Department of Pediatrics with a fever of uncertain source between July and September 2008. Spinal taps were performed according to clinical symptoms and physical examination. Serum PCT levels were measured using an enzyme-linked fluorescent assay. Results : Seventy-one infants (mean age, 2.62 months) were studied. Twenty-six infants (36.6%) had urinary tract infections (UTIs), and 22 infants (31.0%) had viral meningitis. The remaining infants had acute pharyngitis (n=1), herpangina (n=1), upper respiratory tract infections (n=7), acute bronchiolitis (n=8), acute gastroenteritis (n=4), and bacteremia (n=2). The median WBC and CRP levels were significantly higher in infants with UTIs than in infants with viral meningitis. However, there were no differences in the median PCT levels between the groups (0.14 ng/mL vs. 0.11 ng/mL, P=0.419). The area under the receiver operating characteristic curve was 0.792 (95% CI, 0.65-0.896) for WBC, 0.77 (95% CI, 0.626-0.879) for CRP, and 0.568 (95% CI, 0.417-0.710) for PCT. An elevated WBC count (>11,920/${\mu}L$) and an increased CRP level (>1.06mg/dL) were significant predictors of UTIs based on multiple logistic regression analysis. Conclusion : Serum PCT concentrations should be interpreted with caution in infants <6 months of age with a fever of uncertain source.

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A Criteria on Nitrate Concentration in Soil Solution and Leaf Petiole Juice for Fertigation of Cucumber (Cucumis sativus L.) under Greenhouse Cultivation (시설 오이의 관비재배를 위한 토양용액과 엽병즙액중 질산태 농도 기준 설정)

  • Lim, Jae-Hyun;Lee, In-Bog;Kim, Hong-Lim
    • Korean Journal of Soil Science and Fertilizer
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    • v.34 no.5
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    • pp.316-325
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    • 2001
  • To develope a technique for efficiently managing fertilizer for cucumber, a quick test method to quantify nitrate content in soil solution and leaf petiole juice using a simple instrument was investigated. Among the nitrate analyzing instruments such as compact ion meter, nitrate ion meter, and test strip with reflectometer, the paper test-strip used in conjunction with a hand-held reflectometer was most closely correlated with ion chromatography method in nitrate content, and then it would be suggested with a tool that a farmer can use rapidly, conveniently and accurately for nitrate analysis in a field. Nitrate content in soil solution collected by porous cup was very variable on the lapsed time after drip irrigation and the sampling positions such as soil depth and the distance from dripper. As a result, a significant correlation between nitrate contents of soil solutions and 2M KCl soil extract was not found. However, nitrate content in soil solution extracted with a volume basis (soil:water=1:2) showed the highly significant correlation with that in 2M KCl extract. Nitrate contents of cucumber leaf petiole juices was greatly different between upper and lower leaves. Eleven to sixteen positioned-leaf would be a proper sampling position to determine nitrate content in leaf petiole for evaluating nutrient state by plant tissue analysis. From the secondary regression equations between nitrate contents of soil and petiole juice and the yield of cucumber, nitrate levels for real time diagnosis were estimated as $400mg\;l^{-1}$ soil solution by porous cup. $300mg\;l^{-1}$ in a soil volume extraction, and $1400mg\;l^{-1}$ in petiole juice from spring to summer season. In addition, the maximum yield of cucumber fruit in pot test was obtained in nitrate $1500mg\;l^{-1}$ level of petiole juice, which was similar to nitrate $1400mg\;l^{-1}$ in greenhouse trial.

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Origin of Sandstone Fragments Within Core Sediments Obtained from Southwestern Continental Shelf of the Ulleung Basin, East Sea (동해 울릉분지 남서부 대륙붕에서 채취된 시추퇴적물내 사암편의 기원)

  • Lee, Eui-Hyeong;Lee, Yong-Kuk;Shin, Dong-Hyeok;Huh, Sik;Kim, Seong-Ryul;Jeong, Baek-Hoon;Han, Sang-Joon;Chun, Jong-Hwa
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.6 no.3
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    • pp.126-134
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    • 2001
  • Several angular sandstone fragments (about 7 cm in longest diameter) occur in two piston cores, obtained from the submarine trough in the northeastern part of Korea Strait. The origin of the sandstone fragments and the paleoenvironment of trough sediment could be suggested from sedimentary facies analysis of cores and identification of ostracod within sandstone fragments. Echo characteristics around two core sites in submarine trough represent the prolonged bottom echoes with diffuse or no subbottom reflectors. The cores consist of a lower bioturbated mud and an upper gravelly sand sediments with sandstone/shell fragments. The bioturbated mud sediments show low water contents (27-44%) and high shear strength (19.2->37 kPa) compared with those of Holocene sediments (60-219% and 1.0-2.7 kPa, respectively) in the inner shelf and continental slope. However, clay contents (48-56%) of the bioturbated mud sediments are similar to those of fluviatile Holocene sediments in the inner shelf. The mean grain size of gravelly sand sediments ranges from 2.3 to 3.0 ${\phi}$ and shows coarsening upward with sandstone/shell fragments. The Holocene palimpsest in the continental shelf are composed of muddy sand sediments or sandy mud sediments (mean grain size: 4.6-7.6 ${\phi}$). Those suggest that two core sediments might be formed from Paleofluvial and paleocoastal deposits during sea-level lowstand. However, sandstone fragments mainly consist of quartz grains and bioclasts, with carbonate matrix, hollow pore, and glauconite. Two extinct ostracod species, Normanicythere sp. and Kotoracythere sp., are recovered in the sand-stone fragments of core EP-7, and they continued to exist from late Pliocene to early Pleistocene in cold water environment of this area. Thus, the sandstone fragments are interpreted to be formed at the paleocoastal environment derived from the Plio-Pleistocene outcrops exposed around the submarine trough during the LGM (Last Glacial Maximum) period.

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Tidal-Flat Sedimentation in a Semienclosed Bay with Erosional Shorelines: Hampyong Bay, West Coast of Korea (해안침식이 우세한 반폐쇄적 조간대의 퇴적작용: 한국 서해안의 함평만)

  • Chang, Jin-Ho;Kim, Yeo-Sang;Cho, Yeong-Gil
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.4 no.2
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    • pp.117-126
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    • 1999
  • Hampyong Bay is a semienclosed and macrotidal bay which opens to the eastern Yellow Sea through a narrow inlet in the southwestern coast of Korea. In order to understand the tidal-flat sedimentation in the semienclosed setting, morphology, sediments, accumulation rate and sea cliff erosion were investigated in the tidal flat of Hampyong Bay. The tidal flat of Hampyong Bay lacks intertidal drainage systems, and generally shows the concave-upward profile whose relief is designated by marked morphological features such as high-tide beaches, intertidal sand shoals and tidal creeks. Surfacial sediments of the tidal flat mainly consist of mud, sandy mud, gravelly mud, gravelly sand and muddy gravel, thus showing the textural characteristics of multimodal grain-size distribution, poorly sorting and positive skewness. The sediments generally coarsen landward due to the increase in coarse fraction content. Sedimentary structures are deeply bioturbated, but parallel lamination and lenticular bedding are locally found in the mudflat near mean low water line. Annual accumulation rates across the tidal flat (along Line SM) average -5.2 cm/yr with a range of -45.8~+4.2 cm/yr, indicating that the tidal flat is erosional. In general, erosion rates of upper and lower tidal flat are higher than those of middle tidal flat. Seasonally, the erosion rates are much higher during spring and winter when dominant wind direction corresponds to the long axis of Hampyong Bay. Sea cliffs are eroded at a rate of 1.4 m/yr. The biggest sea cliff erosion generally occurs 1~2 months later after tidal flats were extensively eroded. Such erosions of tidal Oats and sea cliffs in the semienclosed bay setting are interpreted to be due to wind waves coupled with local sea-level rise.

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Effects of Dietary Energy Level and Slaughter Weight on Growth Performance and Grades and Quality Traits of the Carcass in Finishing Pigs (비육돈에서 사료의 에너지 수준과 도살체중이 성장성적과 도체의 등급 및 육질특성에 미치는 영향)

  • Park, Man-Jong;Jeong, Jin-Yeun;Ha, Duck-Min;Han, Jeong-Cheol;Sim, Tae-Geon;Park, Byung-Chul;Park, Gu-Boo;Joo, Seon-Tea;Lee, Chul-Young
    • Journal of Animal Science and Technology
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    • v.51 no.2
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    • pp.143-154
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    • 2009
  • (Y $\times$ L) $\times$ D-crossbred gilts and barrows weighing $80.2\pm0.2$ kg were fed a "medium-energy" (ME) or "low-energy" (LE) diet (3.2 vs 3.0 M cal DE/kg) and slaughtered at 110, 125, or 138 kg, after which physicochemical and sensory quality traits of major primal cuts of resulting carcasses were analyzed, under a 2 (sex) $\times$ 2 (diet) $\times$ 3 (slaughter weight; SW) factorial arrangement of treatments. The ADG and ADFI were greater (P<0.01) in barrows than in gilts and also in 125- and 138-kg vs 110-kg SW. Moreover, ADG and gain:feed were greater in ME vs LE (P<0.01), whereas ADFI was greater in LE vs ME (P<0.01). Backfat thickness, which increased with increasing SW (P<0.01), was not affected by sex or diet. Carcass marbling score was greater (P<0.01) in gilts and LE than in barrows and ME, respectively. Carcass quality grade, which was superior in LE vs ME, was not affected by SW, whereas the yield grade decreased abruptly between 125- and 138-kg SW primarily due to the upper limit of carcass weight imposed on the A and B grades. Physicochemical characteristics including pH, drip loss, and variables pertaining to color of belly, ham, and loin were not affected significantly by any of the treatment factors, albeit statistically significant in some cases, in terms of quality criteria. In sensory evaluation, the acceptability of fresh belly was not influenced by any of the treatment factors. Marbling score of fresh ham was greater in LE vs ME (P<0.01) and tended to increase between 110- and 125-kg SW (P=0.10); in loin, the increase of this variable between the two SW was significant (P<0.01). Following cooking, LE was superior to ME in the acceptability in belly and ham, but the effect of SW was insignificant in any of the sensory quality traits evaluated in this study in any of the three major primal cuts. In conclusion, the present results suggest that SW can be increased to up to 138 kg without compromising carcass quality and that LE has some beneficial effects on quality of the whole carcass and the major primal cuts.

A Case of the Shoulder-Hand Syndrome Caused by a Crush Injury of the Shoulder (견관절부 외상후 발생된 Shoulder-Hand Syndrome)

  • Jeon, Jae-Soo;Lee, Sung-Keun;Song, Hoo-Bin;Kim, Sun-Jong;Park, Wook;Kim, Sung-Yell
    • The Korean Journal of Pain
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    • v.2 no.2
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    • pp.155-166
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    • 1989
  • Bonica defined, that reflex sympathetic dystrophy (RSD) may develop pain, vasomotor abnoramalities, delayed functional recovery, and dystrophic changes on an affected area without major neurologic injury following trauma, surgery or one of several diseased states. This 45 year old male patient had been crushed on his left shoulder by a heavily laden rear car, during his job street cleaning about 10 years ago (1978). At first the pain was localizea only to the site of injury, but with time, it spreaded from the shoulder to the elbow and hand, with swelling. X-ray studies in the local clinic, showed no bone abnormalities of the affected site. During about 10 years following the injury, the had recieved several types of treatments such as nonsteroidal analgesics, steroid injections into the glenoidal cavity (10 times), physical therapy, some oriental herb medicines, and acupuncture over a period of 1~3 months annually. His shoulder pain and it's joint dysfunction persisted with recurrent paroxysmal aggrevation because of being mismanaged or neglected for a sufficiently long period these fore permiting progression of the sympathetic imbalance. On July 14 1988 when he visited our clinic. He complained of burning, aching and had a hyperpathic response or hyperesthesia in touch from the shoulder girdle to the elbow and the hand. Also the skin of the affected area was pale, cold, and there was much sweating of the axilla and palm, but no edema. The shoulder girdle was unable to move due to joint pain with marked weakness. We confirmed skin temperatures $5^{\circ}C$ lower than those of the unaffected axilla, elbow and palm of his hand, and his nails were slightly ridged with lateral arching and some were brittle. On X-ray findings of both the shoulder AP & lateral view, the left humerus and joint area showed diffuse post-traumatic osteoporosis and fibrous ankylozing with an osteoarthritis-like appearance. For evaluating the RSD and it's relief of pain, the left cervical sympathetic ganglion was blocked by injecting 0.5% bupivacaine 5 ml with normal saline 5 ml (=SGB). After 15 minutes following the SGB, the clinical efficacy of the block by the patients subjective score of pain intensity (=PSSPI), showed a 50% reduction of his shoulder and arm pain, which was burning in quality, and a hyperpathic response against palpation by the examiner. The skin temperatures of the axilla and palm rose to $4{\sim}5^{\circ}C$ more than those before the SGB. He felt that his left face and upper extremity became warmer than before the SGB, and that he had reduced sweating on his axilla and his palm. Horner's sign was also observed on his face and eyes. But his deep shoulder joint pain was not improved. For the control of the remaining shoulder joint pain, after 45 minutes following the SGB, a somatic sensory block was performed by injecting 0.5% bupivacaine 6 ml mixed with salmon calcitonin, $Tridol^{(R)}$, $Polydyn^{(R)}$ and triamcinolone into the fossa of the acromioclavicular joint region. The clinical effect of the somatic block showed an 80% releif of the deep joint pain by the PSSPI of the joint motion. Both blocks, as the above mentioned, were repeated a total of 28 times respectively, during 6 months, except the steroid was used just 3 times from the start. For maintaining the relieved pain level whilst using both blocks, we prescribed a low dose of clonazepam, prazocin, $Etravil^{(R)}$, codeine, etodolac micronized and antacids over 6 months. The result of the treatments were as follows; 1) The burning, aching and hyperpathic condition which accompanied with vaosmotor and pseudomotor dysfunction, disappeared gradually to almost nothing, within 3 weeks from the starting of the blocks every other day. 2) The joint disability of the affected area was improved little by little within 6 months. 3) The post-traumatic osteoporosis, fibrous ankylosis and marginal sclerosis with a narrowed joint, showed not much improvement on the X-ray findings (on April 25, 1989) 10 months later in the follow-up. 4) Now he has returned to his job as a street cleaner.

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Total Spinal Block and Cortical Epidural Block for Whiplash Syndrome and Reflex Sympathetic Dystrophy (Report of Four Cases) (전척수(全脊髓) 및 경막외차단(硬膜外遮斷)으로 편타성(鞭打性) 손상(損傷)의 통증치험(痛症治驗) (4례(例) 보고(報告)))

  • Park, Wook;Ok, See-Young;Song, Hoo-Bin
    • The Korean Journal of Pain
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    • v.1 no.1
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    • pp.106-119
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    • 1988
  • For the relief of pain in 3 cases of whiplash syndromes (case I, II and IV) and in one of reflex sympathetic dystrophy (case III), we have carried out six intentional. total spinal blocks (TSB) which attempted two times in case I, three in case II and one in carte III whoso various symptoms were chronically unresponsive to the usual conservative treatments, and a time of cervical epidural and right suprascapular nerve block in case W whose acute symptom lasted 4 drys following the cervical injury (see fables from 1 to 9). During the 753, we have observed clinically the sequential charges of respiration, lid and pupil reflexes, body motion and consciousness. And checked the blood pressure, pulse rate and arterial Pco2. The effectiveness of those blocks has been assessed by using the Visual Analog Scale which is designed to measure the patient$\acute{s}$ subjective intensity of pain and also we have found out the sequelae following those blocks. The methods of the blocks were as the following: 1. Under the N.P.O. for 8~10 hours, the preparations of immediate cardiopulmonary resuscitation and premedication with atropine 0.5mg at thirty minutes before the TSB, it was performed by injecting the mixture of 2% mepivacaine 10 or 15ml and normal saline 10 or 5ml through No. 23 G. spinal needle into the subarachnoid space of $C_7-T_1$ interspinous region with fully flexed neck on the lateral posture. Immediately after the injection of the local anesthetic in the lateral position, the patient$\acute{s}$ were hasten to change Trendelenburg$\acute{s}$ position in order to act the drugs cephalad and to make easy controlled respiration with oxygen. 2. The cervical epidural block was done by injecting the mixture of 0.5% bupivacaine 4ml, normal saline 4ml and triamcinolone 15mg through No. 18 G. Tuohy needle into the epidural space on the same region and posture as the above without premedication.7he suprascapular nerve block was done by injecting of 0.5% bupivacaine 3ml only into the right suprascapular fossa on the sitting posture. The results were as the following: 1. The cessation of respiration was seen within 5 minutes following the subarachnoidal injection of the above 20ml mixture in 2 to 3 minutes and then soon the consciousness began to disappear. The loss of Lid and pupil reflexes noted between 5 to 10 minutes and the size of the dilated pupils was equal between 5 to 20 minutes, but the pupil of the dependent side on tile lateral position was dilated 1 to 3 minutes earlier than that of the independent. The patients had r=ever responded to any stimulations during the TSB except their heart funtion. 2. The recovery of the TSB was as the following, firstly the ankle and lower limb of the independent side began to move slightly with in 34 to 75 minutes after the injection and then that of the dependent Secondly the neck and upper limb moved 6 to 15 minutes later than the lower limb. Thirdly the self respiration began to appear between 40 to 80 minutes from the block. The lid and pupil reacted to touch and light respectively between 40 to 80 minutes but the pupil of the independent side responded earlier than that of the depends. Lastly the consciousness recovered completely between 80 to 125 minutes from the block. 3. In the cardiopulmonary function during the TSB, the blood pressure were stable except the 210/130 tory at the and block of case I. There were bradycardias between 65 to 85 minutes in case I and II but no arrythmia on the EKG. The level of the arterial Pco2 was maintained to 43~45 torr during the TSB. 4. The effectiveness of the above blocks was no pain(0%) in case IV, and light (10~20%) in case I and II but no improvement in case III. 5. The right arm weakness has been complicated as to be Injected accidently the "COLD" local anesthetic at the End block of case I.

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FRACTURE RESISTANCE OF THE THREE TYPES OF UNDERMINED CAVITY FILLED WITH COMPOSITE RESIN (복합 레진으로 수복된 세 가지 첨와형태 와동의 파절 저항성에 관한 연구)

  • Choi, Hoon-Soo;Shin, Dong-Hoon
    • Proceedings of the KACD Conference
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    • 2008.05a
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    • pp.177-183
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    • 2008
  • It was reported that esthetic composite resin restoration reinforces the strength of remaining tooth structure with preserving the natural tooth structure. However, it is unknown how much the strength would be recovered. The purpose of this study was to compare the fracture resistance of three types of undermined cavity filled with composite resin with that of non-cavitated natural tooth. Forty sound upper molars were allocated randomly into four groups of 10 teeth. After flattening occlusal enamel. undermined cavities were prepared in thirty teeth to make three types of specimens with various thickness of occlusal structure (Group $1{\sim}3$). All the cavity have the 5 mm width mesio-distally and 7 mm depth bucco-lingually. Another natural 10 teeth (Group 4) were used as a control group. Teeth in group 1 have remaining occlusal structure about 1 mm thickness, which was composed of mainly enamel and small amount of dentin. In Group 2, remained thickness was about 1.5 mm, including 0.5 mm thickness dentin. In Group 3, thickness was about 2.0 mm, including 1 mm thickness dentin. Every effort was made to keep the remaining dentin thickness about 0.5 mm from the pulp space in cavitated groups. All the thickness was evaluated with radiographic Length Analyzer program. After acid etching with 37% phosphoric acid, one-bottle adhesive (Single $Bond^{TM}$, 3M/ESPE, USA) was applied following the manufacturer's recommendation and cavities were incrementally filled with hybrid composite resin (Filtek $Z-250^{TM}$, 3M/ESPE, USA). Teeth were stored in distilled water for one day at room temperature, after then, they were finished and polished with Sof-Lex system. All specimens were embedded in acrylic resin and static load was applied to the specimens with a 3 mm diameter stainless steel rod in an Universal testing machine and cross-head speed was 1 mm/min. Maximum load in case of fracture was recorded for each specimen. The data were statistically analyzed using one-way analysis of variance (ANOVA) and a Tukey test at the 95% confidence level. The results were as follows: 1. Fracture resistance of the undermined cavity filled with composite resin was about 75% of the natural tooth. 2. No significant difference on fracture loads of composite resin restoration was found among the three types of cavitated groups. Within the limits of this study, it can be concluded the fracture resistance of the undermined cavity filled with composite resin was lower than that of natural teeth, however remaining tooth structure may be supported and saved by the reinforcement with adhesive restoration, even of that portion consists of mainly enamel and a little dentin structure.

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Vegetation Change of Long-Term Ecological Research (LTER) Site of Abies koreana Forests in Hallasan Mountain (Yeongsil Area) (한라산(영실) 장기생태연구(LTER) 조사지 구상나무 숲 식생 변화)

  • Song, Kuk-Man;Kim, Jae-Hoon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.21 no.1
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    • pp.1-12
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    • 2018
  • This study sought to analyze changes in the vegetation structure and species diversity indices in the Abies koreana forest in the Yeongsil area of Hallasan Mountain and establish basic data for Long-Term Ecological Research (LTER). The results show that the number of woody plants per 1ha has increased by 804 (45.1%) from 1,781 to 2,585 individual plants, whereas the number of live A. koreana did not change much with 796 individual plants. The number of dead tree plants, however, jumped by 807 (82.2%) from 982 to 1,789 plants. With other tree species, the number of live individual plants increased by 807 (82.2%) from 982 to 1,789 plants, whereas the number of dead plants increased by 31 from 10 to 41 individual plants. Results of the average importance index analysis show that the number of A. koreana decreased, while the number of Weigela subsessilis, Rhododendron yedoense for. poukhanense, and Magnolia sieboldii increased. The species diversity index increased by 6.7% as per the maximum level in the upper layer and by 7.2% in the lower layer, respectively. Results of the stem morphology analysis show that the number of AS type was highest with 700 individual plants among A. koreana, while their distribution by type shifted from AS>AL>DS>DB to AS>DS>AL>DB. As for other species, the AS type was most abundant with 1,580 individual plants, while their distribution by type shifted from AL>AS>AF>AB to AS>AL>AB>AD. The number of newly sprouted tree plants has increased from 420 in 2014 to 453 in 2016. Of the individual plants that were alive in 2014, 23 were found dead and 33 individual plants younger than 3 years old have been newly added to the group. The number of deaths after 2014 was highest among the 2 years olds, whereas the number of 2 years olds that sprouted in 2014 was highest among the newly sprouted tree plant group. In the A. koreana forest in Yeongsil, the density of other species was rising rapidly with the exception of the dead and live A. koreana. The occurrence of new tree plants is decreasing rapidly, thereby confirming the rapid change in the area's vegetation structure. Therefore, there is a need for continuous long-term ecological research to monitor vegetation change. It can also be used as a basic data for efficient restoration research.