• 제목/요약/키워드: N-fixation

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두과 작물의 질소고정과 유기조사료생산을 위한 작부체계 (Nitrogen Fixation of legumes and Cropping System for Organic Forage Production)

  • 이효원;박형수
    • 한국유기농업학회지
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    • 제10권1호
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    • pp.49-63
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    • 2002
  • In order to supply 85% of total organic feed in ruminants and 80% in non-ruminants for organic animal production, nitrogen fixation ability of legume should be used in domestic roughages production. 50% of Europe organic farmer use intercropping legume in as green manure. This article is dealing with amount of biologically fixed nitrogen used by legumes and methods for estimating the transfer of biologically fixed N in rotation and separating the N benefit into fixed N and non-fixed N components are reviewed. Available data indicate that transfer amount of N to non legumes was from 50∼9.6(kg/ha) in legume-cereal rotations and proportion of legume N varied with seasons, 90% in summer, 50% in autumn. The important point in cropping system for legumes have to be included for organic forage production 6 year rotation is based on pasture system of 3 year pasture + 2 year annual(com, sudangrass), again pasture. Rye, barly and Italian ryegrass+legumes(vetch, crimson and pea) can be one of option in spring, com, soybean, sudangrass and Japanese bamyard millet would be seeded after spring harvest in the field. Farmer can make good use of rice paddy field as forge production potential area after harvesting rice. Italian, burly and rye+vetch and crimsonclover may be grown in autumn or spring time at the rice field.

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무기질소원의 종류에 따른 염조류 Anabaena flos-aquae 광합성의 특성 (Photosynthetic Characteristics of Anabaena flos-aquae Growing on Various Inorganic Nitrogen Sources)

  • 맹주선
    • Journal of Plant Biology
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    • 제25권4호
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    • pp.153-160
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    • 1982
  • The kinetics of $^{14}C$ fixation have been investigated in Anabaena flos-aquae growing on ${NH}_4+$,$NO_3-$ and $NO_2-N$ in batch cultures. Growth rate was highest with ${NH}_4+$, followed by $NO_2-$ and finally $NO_2$. The compensation intensity($I_0$) and the half-saturation irradiance($K_1$) with $K_1$ were higher than with other N sources, but the maximum C fixation rate($P_{max}$) was lower. The ($P_{max}$)/$K_1$ ratio, which is analogous to quantum efficiency at low irradiance ranges, was also lower with $N_2$. All these parameters except $K_1$ decrease with culture age, or decreasing growth rate. Since $^{14}C$ uptake measures net photosynthesis, the higher values of $I_0$ and $K_1$, and the low values of $P_{max}$/$K_1$ ratio with $N_2$ appear to be related to the high energy demand of $N_2$fixation. They may also be related to the lox maximum growth rate with $NO_2-N$.

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전방십자인대 재건시 이식건의 대퇴골측 고정에 대한 주기성인장부하의 효과 (The Effect of Cyclic Load on Different Femoral Fixation Techniques in Anterior Cruciate Ligament Reconstruction)

  • 송은규;김종석
    • 대한정형외과스포츠의학회지
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    • 제2권1호
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    • pp.28-36
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    • 2003
  • 목적: 전방십자인대재건술의성공에영향을미치는요인가운데수술후초기단계에는이식건에대한고정력이가장중요한인자로알려져있으며, 지금까지여러가지의고정방법들이사용되고있다. 저자는전방십자인대재건술후대퇴골측의초기안정성을알아보기위하여현재주로쓰이고있는6가지의고정방법들에대하여주기성인장부하검사를시행하기전,후의최대인장력을측정하여그결과를비교하고, 실패양상을관찰하고자하였다. 대상및방법: 돼지(Yorkshire) 슬관절72개를이용하여6가지고정방법(슬괵건-LA나사(R), 슬괵건-생체흡수성간섭나사, 슬괵건-Semifix 나사(R), 슬괵건-Endobutton(R)고정, 슬개건-티타늄간섭나사, 슬개건-생체흡수성간섭나사)으로이식건을고정하고 Instron(R) 인장검사기를이용하여주기성인장부하검사및최대실패인장력검사를시행하였다. 주기성인장부하검사는50 mm/min의속도로 30N에서 150N사이를1000회주기적으로반복하도록하였으며, 동일시편으로최대인장력검사를 시행하여주기성부하 후 최대 인장력의 변화를 비교, 분석하였다. 각 실험군에 따른 인장력 차이의통계적 유의성은ANOVA와Duncan 다중비교분석법을이용하였다. 결과: 주기성인장부하전,후이식건의최대인장력은슬괵건-LA나사(R) 군이평균1003.4$\pm$145N에서601.1$\pm$154N으로, 슬괵건-생체흡수성간섭나사군이평균 595.5$\pm$104N에서평균360.7$\pm$56N으로, 슬괵건-Semifix(R) 군이평균1431.7$\pm$135N에서평균710.7$\pm$114N으로, 슬괵건-Endobutton(R) 고정군이평균603.6$\pm$54N에서평균459.1$\pm$46N으로, 슬개건-티타늄 간섭나사군이평균 1067.4$\pm$145N에서평균 601.8$\pm$134N으로, 슬개건-생체흡수성간섭나사군이평균 987.1$\pm$168N에서588.7$\pm$124N으로각각40$\%$, 39$\%$, 50$\%$, 24$\%$, 44$\%$, 40$\%$가감소하였다. 결론: 수술후초기고정력은슬괵건을LA나사(R) 또는Semifix(R)로고정하는방법과슬개건을티타늄및생체흡수성간섭나사로고정하는방법등이우수하였으며, 슬괵건을생체흡수성간섭나사나Endobutton(R)으로 고정하는 방법 등은고정력이 상대적으로매우약함을 알수있었다. 최대인장력은단순인장검사로는이상의대퇴골측고정방법의고정력이초기부하를견뎌내는데충분하다고생각되었으나주기성부하실험후현저히감소되어충분한초기안정성을제공하지못함을알수있었다.

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개방형 자동굴절검사기의 주시거리에 따른 굴절이상도와 가상주시형 자동굴절 검사기의 굴절이상도와의 비교 연구 (A Study of Comparison Between Refractive Errors by Fixation Distance Variation with N-vision(open-view type) Auto-refractor and Refractive Error with Canon(Internal Fixation Target Type) Auto-refractor)

  • 김재도;김대현;전인철
    • 한국안광학회지
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    • 제16권4호
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    • pp.433-438
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    • 2011
  • 목적: 개방형과 가상주시형 자동굴절검사기에 의한 굴절이상도를 비교하여 그 차이를 알아보고 개방형 검사기를 이용하여 정적굴절검사를 시행할 때 주시시표와 피검자와의 최소거리를 알아보고자 하였다. 방법: 교정시력 1.0 이상이고 안과적 질환이 없는 성인(22.2${\pm}$3.4세) 21명(42안)을 대상으로 자동굴절검사기에 의한 굴절검사를 실시하였다. 굴절검사는 가상주시형(RK-F1, Canon, Japan)을 사용하였으며 개방형(N-vision-K5001, Shin-nippon, Japan)을 사용하여 1 m, 3 m, 4 m, 6 m의 위치를 주시하는 상태에서 거리에 따른 굴절이상도를 비교하였다. 결과: 1 m 주시거리에서 개방형에 의한 전체대상자의 평균 굴절이상도(-2.75${\pm}$1.84 D)는 가상주시형에 의한 평균 굴절이상도(-2.95${\pm}$2.04 D)와 유의적인 차이가 없었다(p=0.06). 그러나 3 m, 4 m, 6m 주시거리에서 개방형에 의한 평균굴절이상도는 가상주시형에 의한 굴절이상도보다 낮은 근시성 굴절이상도를 보였다(p<0.05). 결론: 정적굴절검사를 위해 개방형 굴절검사기를 사용하는 경우 5~6 m의 검사거리를 확보하지 않더라도 3 m 이상의 측정거리에서도 가능하다.

후방까지 연장된 안와하벽골절에서 안구함몰 예방을 위한 Medpor® 내고정술 (Internal Fixation of Medpor® Implant for Prevention of Enophthalmos in Posteriorly Extended Orbital Floor Fracture)

  • 석정훈;지소영;김태범;양완석
    • 대한두개안면성형외과학회지
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    • 제9권2호
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    • pp.55-61
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    • 2008
  • Purpose: The purpose of this study is to evaluate the effectiveness of internal fixation method of $Medpor^{(R)}$ implant with $BioSorb^{TM}FX$ screw which is used for prevention of enophthalmos in posteriorly extended large orbital floor fracture. Methods: From Jun. 1997 to Dec. 2007, 21 patients who were diagnosed with posteriorly extended large orbital floor fractures were classified into two groups. One group(n=11) had undergone reduction surgery with regular $Medpor^{(R)}$ sheets without any fixation method, while the other group(n=10) had their $Medpor^{(R)}$ sheets fixed with the $BioSorb^{TM}FX$ screws. The two groups were evaluated by comparison of their enophthalmos degree and effectiveness. Results: In the non-fixation group, six patients had enophthalmos preoperatively and three of them showed persistent enophthalmos postoperatively. In postoperative CT examination, displacement of $Medpor^{(R)}$ implant with soft tissue impaction into maxillary sinus was observed in the patients. In the screw fixation group, three patients had enophthalmos preoperatively, but none of them suffer from complication such as residual enophthalmos, soft tissue impaction, muscle entrapment or optic nerve compression postoperatively. Conclusion: Internal fixation method of $Medpor^{(R)}$ implant with $BioSorb^{TM}FX$ screw on the medial surface of orbital floor provides firm stabilization of implants and surrounding soft tissues and can be an effective option especially when postoperative implant displacement or malposition was expected.

호밀녹비 이용 시 중질소($^{15}N$)를 이용한 질소원 유래별 콩의 집적질소 분획추정 (Estimation of Soybean N Fraction Derived from N Sources by $^{15}N$ in Soybean Cultivation with Rye as Green Manure)

  • 서종호;이성희;조영손;이재은;이충근;권영업
    • 한국작물학회지
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    • 제53권1호
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    • pp.50-57
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    • 2008
  • 월동 후 녹비용 호밀에 시용한 질소가 콩의 질소고정 및 흡수에 미치는 효과를 보기 위하여, 2004년 온실 및 2005년 포장에서 포트시험을 통해 시비질소량별 토양, 호밀 및 콩의 질소회수율을 조사하였다. 1. 2004년 온실폿트 시험에서는 호밀에 시용한 질소비료 량이 증가할수록 호밀지상부가 토양에서보다 질소비료로부터 질소를 흡수하는 비율이 증가하였다. 호밀이 없는 조건에서는 논흙이 밭흙보다 콩의 건물 중 및 질소흡수량이 현저히 증가하였는데, 지력이 높았던 논흙에서는 밭흙에 비해 콩이 질소고정 유래 질소의 비율이 상대적으로 낮아지고 토양유래 질소의 비율이 높았다. 2. 밭흙에서 무녹비와 대비하였을 때 호밀녹비 이용 시의 콩 시비질소회수율은 낮았지만 토양의 시비질소회수율(질소유기화)이 높아 전체회수율은 높았으며, 또 호밀녹비 이용시 콩의 시비질소회수율은 호밀에 대한 질소시용량이 많을수록 증가하였다. 3. 2004년 온실포트 실험에서의 콩의 근류고정유래의 질소비율은 약 $92{\sim}95%$로 2005년 포장포트에서의 $82{\sim}84%$보다 약 10% 정도 높았으며, 콩의 근류고정유래 질소량 및 질소량 분획 추정에서는 2년 모두 Difference method와 $^{15}N$ method간 차이를 보이지 않았다.

A Prospective Study with Cage-Only or Cage-with-Plate Fixation in Anterior Cervical Discectomy and Interbody Fusion of One and Two Levels

  • Kim, Sam Yeol;Yoon, Seung Hwan;Kim, Dokeun;Oh, Chang Hyun;Oh, Seyang
    • Journal of Korean Neurosurgical Society
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    • 제60권6호
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    • pp.691-700
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    • 2017
  • Objective : The authors prospectively analyzed the effect of one-level or two-level anterior cervical discectomy and fusion (ACDF), comparing stand-alone cages and cage-with-plate fixation constructs with respect to clinical outcomes and radiologic changes. Methods : A total of 84 patients who underwent one-level (n=52) or two-level ACDF (n=32) for cervical disc disease and who completed 2 years of follow-up were included in this study. The patients were divided by cervical level and grouped into ACDF-Cage-only and ACDF-Cage-with-plate groups. The following parameters were assessed using radiographs : subsidence, C2-C7 lordosis angle, fusion segment angle, adjacent disc space narrowing, and fusion status. Clinical outcomes were assessed using the neck disability index (NDI) and visual analog scale scores for arm pain. Results : In the comparison of one-level ACDF-cage-only and ACDF-cage-with-plate groups, the NDI score was better in the cage-only group at the 3-, 12-, and 24-month follow-ups : however, no significant difference in clinical outcomes was observed. In the comparison of two-level ACDF-cage-only and ACDF-cage-with-plate groups, no difference in any clinical outcome was observed between the two groups. At the 24-month follow-up, subsidence was observed in 45.8% of patients in the one-level cage-only group and 32.1% of patients in the one-level cage-with-plate fixation group. There was no statistically significant difference in the incidence rate between the two groups (p=0.312). Subsidence in the two-level cage-only group (66.6%) was significantly more frequent than in the two-level cage-with-plate fixation group (30%; p=0.049). The fusion rate for patients in the one-level cage-only group was not significantly different from that in the one-level cage-with-plate fixation group (cage-only, 87.5%; cage-with-plate fixation, 92.9%; p=0.425) ; fusion rate in the two-level patients were also similar between groups (cage-only, 83.3%; cage-with-plate fixation, 95%; p=0.31). Conclusion : Our clinical results showed that for single-level cases, plate fixation had no additional benefit versus cage-only; for two-level ACDF cases, the fusion rate and clinical outcomes were similar, although the cage-with-plate fixation group had a lower incidence of cage subsidence than did the cage-only group. We conclude that physicians should be aware of this possible disadvantage associated with using cervical plates in one-level ACDF. However, in two-level ACDF, subsidence is more likely to occur without plate fixation, and thus the addition of plate fixation should be considered.

A comparison of fixation methods using three-dimensional finite element analysis following anterior segmental osteotomy

  • Yun, Kyoung In;Park, Min-Kyu;Park, Myung-Kyun;Park, Je Uk
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제38권6호
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    • pp.332-336
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    • 2012
  • Objectives: This study sought to evaluate fixation methods and determine the best method for the postoperative stabilization of maxillary osteotomy. For our analysis we performed a three-dimensional finite element analysis of stress distribution on the plate, screw, and surrounding bone, as well as displacement onto the plate. Materials and Methods: We generated a model using synthetic skull scan data; an initital surface model was changed to a solid model using software. Modified anterior segmental osteotomy (using Park's method) was made using the program, and four different types of fixation methods were used. An anterior load of 100 N was applied on the palatal surface of two central incisors. Results: The Type 1 (L-shaped) fixation method gave stresses of 187.8 MPa at the plate, 45.8 MPa at the screw, and 15.4 MPa at the bone around the plate. The Type 2 (I-shaped) fixation method gave stresses of 186.6 MPa at the plate, 75.7 MPa at the screw, and 13.8 MPa at the bone around the plate. The Type 3 (inverted L-shaped) fixation method gave stresses of 28.6 MPa at the plate, 29.9 MPa at the screw, and 15.3 MPa at the bone around the plate. The Type 4 (I-shaped) fixation method gave stresses of 34.8 MPa at the plate, 36.9 MPa at the screw, and 14.9 MPa at the bone around the plate. The deflection of the plates for the four fixation methods was 0.014 mm, 0.022 mm, 0.017 mm, and 0.018 mm, respectively. Conclusion: The Type 3 (inverted L-shaped) fixation method offers more stability than the other fixation methods. We therefore recommend this method for the postoperative stabilization of maxillary osteotomy.

대두근류균(大豆根瘤菌)의 질소고정(窒素固定)에 관한 연구 -III. 신개간지(新開墾地) 토양에서 근류균(根瘤菌)의 접종(接種) 및 개량제시용이 질소고정(窒素固定)과 대두수량에 미치는 효과 (Studies on Symbiotic Nitrogen Fixation in Soybeans -III. Effects of Soil Improvement on N2 Fixation and Yield of Soybean Inoculated with Rhizobium japonicum in Newly Reclaimed Upland Soil)

  • 류진창;이상규;이혁호;홍종운;조무제
    • 한국토양비료학회지
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    • 제16권2호
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    • pp.188-194
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    • 1983
  • 토양비옥도가 극(極)히 낮은 신개간지(新開墾地)에 있어서 근류균(根瘤菌)의 접종(接種) 및 비료(肥料)와 개량제 시용(施用)이 질소고정(窒素固定)과 대두수량에 미치는 영향(影響)을 밝히고자 pot시험(試驗)을 수행하였던 바 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. 대두(大豆) 근류(根瘤)에 의(依)한 질소고정량(窒素固定量)은 근류균(根瘤菌)의 접종(接種)과 비료(肥料) 및 개량제 시용(施用)으로 현저히 증가하였다. 2. 근류균(根瘤菌) 접종(接種)으로 질소흡수량 및 질소고정량(窒素固定量)을 높여 콩수량을 4~10% 증대시켰다. 3. 콩 다수확재배기술체계 확립(確立)을 위하여 토양비옥도가 극(極)히 낮은 신개간지(新開墾地)에서는 개량제의 시용(施用)과 근류균(根瘤菌)과 접종(接種)이 병행되어야 할 것으로 나타났다.

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Xenograft Failure of Pulmonary Valved Conduit Cross-linked with Glutaraldehyde or Not Cross-linked in a Pig to Goat Implantation Model

  • Kim, Dong Jin;Kim, Yong Jin;Kim, Woong-Han;Kim, Soo-Hwan
    • Journal of Chest Surgery
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    • 제45권5호
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    • pp.287-294
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    • 2012
  • Background: Biologic valved grafts are important in cardiac surgery, and although several types of graft are currently available, most commercial xenografts tend to cause early disfiguration due to intimal proliferation and calcification. We studied the graft failure patterns on non-fixed and glutaraldehyde-fixed pulmonary xenograft in vivo animal experiment. Materials and Methods: Pulmonary valved conduits were obtained from the right ventricular outflow tract of eleven miniature pigs. The grafts were subjected to 2 different preservation methods; with or without glutaraldehyde fixation: glutaraldehyde fixation (n=7) and non-glutaraldehyde fixation (n=4). The processed explanted pulmonary valved grafts of miniature pig were then transplanted into eleven goats. Calcium quantization was achieved in all of the explanted xenograft, hemodynamic, histopathologic and radiologic evaluations were performed in the graft which the transplantation period was over 300 days (n=7). Results: Grafts treated with glutaraldehyde fixation had more calcification and conduit obstruction in mid-term period. Calcium deposition also appeared much higher in the glutaraldehyde treated graft compared to the non-glutaraldehyde treated graft (p<0.05). Conclusion: The present study suggests that xenografts prepared using glutaraldehyde fixation alone appeared to have severe calcification compared to the findings of non-glutaraldehyde treated xenografts and to be managed with proper anticalcification treatment and novel preservation methods. This experiment gives the useful basic chemical, histologic data of xenograft failure model with calcification for further animal study.