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Alleviating Effect of the Application of the Easily Decomposable Carbohydrate on Ammonium Toxicity in Chinese Cabbage (Brassica rapa var. chinensis)

  • Ku, Hyun-Hwoi;Lee, Sang-Eun
    • 한국토양비료학회지
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    • 제48권5호
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    • pp.451-455
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    • 2015
  • An excess application of N fertilizer causes physiological and morphological disorder known as ammonium ($NH_4{^+}$) toxicity in Chinese cabbage and it has been to be an issue for appropriate N fertilizer management. Hence, the pot experiment was conducted in order to evaluate the alleviating effect of the application of the easily decomposable carbohydrate on $NH_4{^+}$ toxicity in Chinese cabbage. Four levels of urea at 0, 160, 320, and $640kg\;N\;ha^{-1}$, represented as T1, T2, T3, and T4, respectively, were applied. In order to evaluate the alleviating effect of the application of the easily decomposable carbohydrate (sucrose) at T3 and T4 where $NH_4{^+}$ toxicity had occurred, five levels of sucrose were applied to meet C/N ratios of 0, 2, 4, 6, and 10, respectively. Our results showed that the $NH_4{^+}$ toxicity was observed at T3 and T4 at 5 days after treatment (DAT). $NH_4{^+}$ toxicity contributed to decrease fresh weight, length of leaves, length of root, and number of leaves significantly (p<0.05). The application of sucrose as a source of mitigating $NH_4{^+}$ toxicity had a good performance at T3 with the alleviating effect as 73 % and reduced in $NH_4{^+}-N$ content in soil at 29 DAT. In the maximum N rate of T4, however, sucrose application recovered it as 32 % only compared to T2 even though the same C/N ratio was treated. Consequently, sucrose as the easily decomposable carbohydrate played crucial role to reduce $NH_4{^+}$ concentration in soil and finally alleviated $NH_4{^+}$ toxicity in plant.

A cone-beam computed tomography evaluation of buccal bone thickness following maxillary expansion

  • Akyalcin, Sercan;Schaefer, Jeffrey S.;English, Jeryl D.;Stephens, Claude R.;Winkelmann, Sam
    • Imaging Science in Dentistry
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    • 제43권2호
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    • pp.85-90
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    • 2013
  • Purpose: This study was performed to determine the buccal alveolar bone thickness following rapid maxillary expansion (RME) using cone-beam computed tomography (CBCT). Materials and Methods: Twenty-four individuals (15 females, 9 males; 13.9 years) that underwent RME therapy were included. Each patient had CBCT images available before (T1), after (T2), and 2 to 3 years after (T3) maxillary expansion therapy. Coronal multiplanar reconstruction images were used to measure the linear transverse dimensions, inclinations of teeth, and thickness of the buccal alveolar bone. One-way ANOVA analysis was used to compare the changes between the three times of imaging. Pairwise comparisons were made with the Bonferroni method. The level of significance was established at p<0.05. Results: The mean changes between the points in time yielded significant differences for both molar and premolar transverse measurements between T1 and T2 (p<0.05) and between T1 and T3 (p<0.05). When evaluating the effect of maxillary expansion on the amount of buccal alveolar bone, a decrease between T1 and T2 and an increase between T2 and T3 were found in the buccal bone thickness of both the maxillary first premolars and maxillary first molars. However, these changes were not significant. Similar changes were observed for the angular measurements. Conclusion: RME resulted in non-significant reduction of buccal bone between T1 and T2. These changes were reversible in the long-term with no evident deleterious effects on the alveolar buccal bone.

연속 회분식 반응조의 최적 운전시스템에 관한 연구 (Study on the optimum operation system of Sequencing Batch Reactor)

  • 엄태규;고은주
    • 상하수도학회지
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    • 제13권4호
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    • pp.54-61
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    • 1999
  • SBR process used to evaluate the removal of organics, nitrogen and phosphorus on the basis of a report of research on a precedence at various operation cycle and condition change. Effluent concentration of COD were 50mg/l, 50mg/l, 90mg/l respectively, The removal rates of COD were nearly over 95% at Run 1, 2 and 4. But at Run 3, Effluent concentration of COD was 255.0mg/l, The removal rate of COD was 87% at Run 3. As Oxic/Anoxic rate was fixed and operating cycle of Oxic/Anoxic was changed, the removal rates of T-N were 74.7%, 46.9%, 28.5%, 63.3% respectively at Run 1~4. The case of Run 1 was best result. The removal rates of T-P was appeared in proportion to T-N removal rates and rest of $NO_2-N$. The removal rates of T-P were 51.2%, 35.5%, 41.5%, 51.9% respectively. The removal rates of COD, T-N, T-P were influenced on the change of SBR operation cycle. As organic loading rate was $1.43kgCOD/m^3day$ and C/N ratio was 3.0, operation cycle of Run 1 was best condition of T-N removal rates and T-P removal.

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Poly-Si Thin Film Solar Cells by Hot-wire CVD

  • Lee, J.C.;Chung, Y.S.;Kim, S.K.;Yoon, K.H.;Song, J.S.;Park, I.J.;Kwon, S.W.;Lim, K.S.
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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    • pp.1034-1037
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    • 2003
  • Microcrystalline silicon(c-Si:H) thin-film solar cells are prepared with intrinsic Si-layer by hot wire CVD. The operating parameters of solar cells are strongly affected by the filament temperature ($T_f$) during intrinsic layer. Jsc and efficiency abruptly decreases with elevated $T_f$ to $1400^{\circ}C$. This deterioration of solar cell parameters are resulted from increase of crystalline volume fraction and corresponding defect density at high $T_f$. The heater temperature ($T_h$) are also critical parameter that controls device operations. Solar cells prepared at low $T_h$ ($<200^{\circ}C$) shows a similar operating properties with devices prepared at high $T_f$, i.e. low Jsc, Voc and efficiency. The origins for this result, however, are different with that of inferior device performances at high $T_f$. In addition the phase transition of the silicon films occurs at different silane concentration (SC) by varying filament temperature, by which highest efficiency with SC varies with $T_f$.

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Characterization of ${\mu}c$-Si:H Thin-film Solar Cells by Hot-wire CVD

  • 이정철;정연식;김석기;윤경훈;송진수;박이준;권성원;임광수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 C
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    • pp.1598-1600
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    • 2003
  • Microcrystalline silicon(c-Si:H) thin-film solar cells are prepared with intrinsic Si-layer by hot wire CVD. The operating parameters of solar cells are strongly affected by the filament temperature ($T_f$) during intrinsic layer. Jsc and efficiency abruptly decreases with elevated $T_f$ to $1400^{\circ}C$. This deterioration of solar cell parameters are resulted from increase of crystalline volume fraction and corresponding defect density at high $T_f$ The heater temperature ($T_h$) are also critical parameter that controls device operations. Solar cells prepared at low $T_h$ (<$200^{\circ}C$) shows a similar operating properties with devices prepared at high $T_f$, i.e. low Jsc, Voc and efficiency. The origins for this result, however, are different with that of inferior device performances at high $T_f$. In addition the phase transition of the silicon films occurs at different silane concentration (SC) by varying filament temperature, by which highest efficiency with SC vanes with $T_f$.

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물리치료사의 초음파 작업시 테이블 높이에 따른 척추기립근의 근전도 활동 분석 (Analysis of Electromyographic Activities of Erect Spinae at Different Height of Table during Ultrasound Therapy Work)

  • 김충유;강종호
    • 대한물리의학회지
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    • 제8권3호
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    • pp.289-294
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    • 2013
  • PURPOSE: The purpose of this study was to examine differences in erect spinae activities at different height of table during ultrasound therapy in order to propose a optimum work environment. METHODS: Twenty five healthy adult males and females volunteered to participate in this study. EMG signals of both erector spinae(T10, T12, L2, L4) were recorded throught the surface electromyography system at different height of table(45cm, 56.2cm, 67.5cm) during ultrasound therapy work. RESULTS: The higher table heights was, the lower %RVC of the T10, T12, L2, L4 erect spinae at both sides. The left and right T10, T12 and the left L4 showed significant differences. The lower the spinal level was, the higher %RVC of both erect spinae at 45cm, 56.2cm, 67.5cm. The left erect spinae at 56.2cm, right erect spinae at 45cm, 67.5cm showed significant differences. CONCLUSION: The muscle activities of both erect spinae decreased at higher table height and increased lower spinal level. We identified lower table height are risk factor of spine work related musculoskeletal disorders.

배합사료의 자유 및 제한 급여가 거세한우의 성장단계별 증체, 사료섭취량 및 혈중 대사물질에 미치는 영향 (Effects of Ad libitum and Restricted Feeding of Concentrates on Body Weight Gain, Feed Intake and Blood Metabolites of Hanwoo Steers at Various Growth Stages)

  • 권응기;홍성구;성환후;윤상기;박병기;조영무;조원모;장선식;신기준;백봉현
    • Journal of Animal Science and Technology
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    • 제47권5호
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    • pp.745-758
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    • 2005
  • 본 연구는 한우 거세우 258두를 이용하여 배합사료 자유급여와 제한급여에 따른 증체량, 사료 섭취량, 혈중대사물질의 농도 및 혈액상에 대한 변화를 조사하기 위해 실시하였다. 시험구 배치는 전기간 배합사료 자유급여구(T1)와 생후 6-18개월령 배합사료 제한급여구(T2) 2처리로 하였으며, 배합사료의 제한급여 수준은 육성기에는 체중의 1.2-1.5% 그리고 비육전기에는 체중의 1.7-1.8% 수준으로 하였다. 생후 10-14개월령의 일당증체량은 T2구에 비해 T1구에서 많았으나(p<0.05), 20-24개월에는 T1구에 비해 T2구의 일당증체량이 많았다(p<0.05). 총 건물섭취량의 경우 생후 10, 12 및 16개월령에는 T1구에서, 22개월령에는 T2구에서 상대적으로 높은 결과(p<0.05)를 보였을 뿐 여타 월령에서는 차이가 없었다. 사료요구율은 20-30개월령까지 T1구에 비해 T2구에서 유의적으로 감소하였다(p<0.05). 생후 12, 14, 16 및 18개월령의 혈중 albumin 농도는 T1구에 비해 T2구에서 높았으나(p<0.05), 12-18개월령을 제외한 다른 월령에서는 처리간의 농도 차이는 없었다. 생후 14 및 16개월령의 혈중 triglyceride 농도는 T2구에 비해 T1구에서 높았으며(p<0.05), 8, 10, 16 및 22개월령의 혈중 IP 농도는 T1구에 비해 T2구에서 높았다(p<0.05). 생후 8-12개월령의 MCV와 MCH는 T1구에 비해 T2구에서 낮았으나(p<0.05), 10-12개월 MCHC는 T1구에 비해 T2구에서 높았다(p<0.05). 이상의 연구결과를 종합해 볼 때 육성기 배합사료 제한급여는 비육기 증체에 대한 부의 영향이 없고 비육후기 사료요구율도 감소시키기 때문에 육성기의 배합사료 제한급여가 바람직하다.

Flavobacterium jocheonensis sp. nov., Isolated from Marine Green Alga Ulva pertusa

  • Choi, Ha Ri;Park, So Hyun;Heo, Moon Soo
    • Journal of Microbiology and Biotechnology
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    • 제29권8호
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    • pp.1266-1272
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    • 2019
  • A bacterial strain, labeled $UR11^T$, was isolated from green alga Ulva pertusa collected from Jeju Island, Korea. $UR11^T$ was identified as a gram-negative, rod-shaped, motile by gliding and aerobic bacterial strain with yellow colonies on R2A plates. The strain $UR11^T$ grew over at a temperature range of $10^{\circ}C$ to $30^{\circ}C$ (optimally at $25^{\circ}C$), a pH range of 6.0-11 (optimally at pH 7.0) and a Nacl range of 0.5-5% Nacl (w/v). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain $UR11^T$ was a member of the genus Flavobacterium. Strain $UR11^T$ shared close similarity with F. jejuensis $EC11^T$ (98.0%) F. jumunjinense $HME7102^T$ (96.1%), F. haoranii $LQY-7^T$ (95.3%), F. dongtanense $LW30^T$ (95.1%), and F. ahnfeltiae 10Alg $130^T$(94.9%). The major fatty acids (>5%) were $iso-C_{15:0}$ (33.9%), $iso-C_{15:1}$ G (12.4%), $iso-C_{17:0}$ 3-OH (9.0%), $isoC_{16:0}$ (7.0%) and $iso-C_{15:0}$ 3-OH (6.3%). The major polar lipids were phosphatidylethanolamine, seven unknown aminolipids, two unknown aminopolarlipids and two unknown lipids. DNA-DNA hybridization value was 58% at strain $UR11^T$ with F. jejuensis $EC11^T$. Based on phenotypic, chemotaxonomic and phylogenetic evidence, strain $UR11^T$ represents a novel species of the genus Flavobacterium, for which the name Flavobacterium jocheonensis sp. nov. is proposed. The type strain is Flavobacterium jocheonensis is $UR11^T$ (=KCTC $52377^T$ =JCM $31512^T$).

포장두부에서 분리한 부패세균의 특성에 관한 연구 (A Study on Characteristics of Spoilage Bacteria Isolated from Packed Tofu)

  • 강선희;이용욱;오원택
    • 한국식품위생안전성학회지
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    • 제13권4호
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    • pp.383-387
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    • 1998
  • 본 연구는 포장두부에서 부패 세균을 분리.동정하고, 부패균주의 생육 특성과 내열성을 조사하여 두부 제조공정의 위생관리를 위한 기초 자료로 제시할 목적으로 수행되었다. 포장두부의 부패에 관여하는 세균을 분리하여 Vitek system을 이용하여 동정한 결과, Strain No. T1은 Enterobacter amnigenus일 확률이 92%, Strain No T2는 Flavobacterium indologenes일 확률이 96%이었다. 이들 균주는 $35^{\circ}C$와 pH6.5일 때 가장 생육이 왕성하였다. Enterobacter amnigenus T1의 내열성을 검토한 결과, $60^{\circ}C$에서 2분 처리하였을 경우 초기보다 56.3%, $70^{\circ}C$에서는 37.8%, $80^{\circ}C$에서는 34.0%, $90^{\circ}C$에서 처리했을 때는 22.2%가 잔존하였고, Flavobacterium indologenes T2 경우는 $60^{\circ}C$에서 2분 동안 처리하였을 때 74.8%, $70^{\circ}C$에서는 65.7%, $80^{\circ}C$에서는 37.3%, $90^{\circ}C$에서 처리했을 경우는 9.3%가 잔존하였다.

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양악 수술 시 상악골 상방 이동에 따른 상기도 변화 (A study of upper airway dimensional change according to maxillary superior movement after orthognathic surgery)

  • 김용일;박수병;김종렬
    • 대한치과교정학회지
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    • 제38권2호
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    • pp.121-132
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    • 2008
  • 양악 수술 시 상악골의 상방이동을 시행하였을 경우에 상기도의 공간적 구조변화를 평가하기 위하여, 술전, 술후, 술후 6개월 후의 간격으로 두부규격방사선사진을 촬영하여 그 변화량을 분석해 보았다. 술전 교정치료를 시행하여 상악은 Le Fort I 골절단술로 상방이동 시행하였고 동시에 하악은 후방이동 시키는 수술을 시행 받은 24명을 대상으로 하였다 (평균 연령22세 1개월, 남자 9명 여자 15명). 상악골 상방이동에 대한 상기도 공간의 변화와 그에 따른 관련성을 조사한 결과, PAS (R)부위는 술후 (T1) 감소하였으나 (p<0.01) 술후 6개월 후(T2)에는 다시 증가하여 술전과 비교 시, 크기 변화를 관찰할 수 없었고, PAS (NL) 부위는 술후(T1)와 술후 6개월 후(T2)에서 유의성 있는 크기 증가를 보였다. PAS (OL)의 경우, 술후 (T1)증가를 보이다가 술후 6개월 이후(T2)에서 감소하였다. 연구개의 두께는 술후 (T1) 증가를 보이다가 6개월 이후 (T2) 처음과 같거나 약간 감소하는 것으로 나타났으며 FH-uvular 각도는 술후 6개월 이후 증가하였다. 또한 상악골 상방이동에 대한 상기도 공간의 변화를 회귀분석 시행한 결과 양악수술 시 평균 $4.40{\pm}1.14mm$의 상악골 상방이동은 양악 수술 후 상기도 공간의 변화에 큰 영향을 미치지 않는 것으로 나타났다.