• Title/Summary/Keyword: rapid closure

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Genotypic Variation of Rapid Canopy Closure and Its Relationship with Yield of Rice (벼 조기초관폐쇄성의 품종 변이 및 수량과의 관계)

  • Fu, Jin-Dong;Lee, Byun-Woo
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.53 no.2
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    • pp.137-143
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    • 2008
  • Rapid canopy closure (RCC) is one of the physiological attributes that may enhance genetic yield potential of rice (Oryza sativa L.) in a growing season. Crop growth before canopy closure could be described by an exponential equation of $y\;=\;{\alpha}{\cdot}{\exp}({\beta}{\cdot}t)$ where $\alpha$ is the crop leaf area index (LAI) or shoot dry weight (DW), t is the thermal time, $\beta$ is the LAI or DW at the beginning of the exponential growth and is the relative growth rate of LAI ($m^2m^{-2}^{\circ}C^{-1}$) or DW($gg^{-2}^{\circ}C^{-1}$). Field experiment using 22 cultivars revealed that the exponential growth phase before canopy closure can be divided into two sections; an earlier section during which crop dry weight and LAI of varieties are highly dependent on $\alpha$ and a second section where crop dry weight and LAI are highly dependent on $\beta$. Grain weight had significantly positive correlation with $\alpha$ parameter and dry weight and LAI during early exponential phase. The parameter $\beta$ of the exponential growth curve had positive and significant correlation with the LAI and dry weight during the late exponential growth phase, grain number per unit area, and grain yield. There was genotypic difference for RCC parameters, $\alpha$ and $\beta$, indicating the possibility of genetic improvement for these traits.

Study on a Multi-pipe Water Hammer Phenomenon by using CFD of Rapid Valve Closing (전산유체해석(CFD)을 이용한 밸브의 급폐쇄에 따른 다중 배관 수격 현상에 관한 연구)

  • Park, No-Suk;Kim, Seong-Su;Kang, Moon-Sun;Choi, Jong-Woong
    • Journal of Korean Society of Water and Wastewater
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    • v.27 no.4
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    • pp.479-487
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    • 2013
  • This study was to investigate characteristics for the pressure wave propagation and the maximum pressure near a rapid closure valve which was installed the end of multi piping network. The multi piping network consists of one inlet and three outlet with straight pipes. The diameter of the pipes including the valve was 100 mm, 80 mm, 80 mm respectively. The valve was rapidly closed with the instantaneous time which was 0.023s in the level for the water hammer. For the simulation, the influence of the pipe thickness and deformation due to pressure-wave-propagation was not considered. CFD was conducted under the following condition : the initial pressure was 1bar in the inlet and the mass flow rate was 7.83 kg/s in the outlet(the velocity in the pipe with 100 mm diameter was 1 m/s). As the valve have conditions that were status with and without fluid flow in the pipe after valve closing, the maximum pressure change and the frequency analysis were examined. As the results, the case that was status with fluid flow appeared the higher maximum pressure than another's, the maximum frequency band was about 10 ~ 11 Hz.

PDA Clipping by Using 2mm Thoracoscope (2 mm 흉강경을 이용한 동맥관 개존증 폐쇄술 -1례보고-)

  • Moon, Seung-Chul;Yang, Jin-Young;Koo, Won-Mo;Lee, Gun;Lee, Hyeon-Jae;Lim, Chang-Young
    • Journal of Chest Surgery
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    • v.33 no.1
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    • pp.85-87
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    • 2000
  • Patent ductus arteriosus(PDA) is a common congenital heart disease encountered in premature neonates infants and children. Patent ductus arteriosus was the first surgically managed congenital heart disease,. Classic surgical interruption of patent ducturs arteriosus was partially replaced by a transcatheter endovascular closure, After a 5-7 mm video-assisted thoracoscopic interruption of the patent ductus arteriosus first applied in 1991, this minimally invasive technique came to be used in many centers, Video-assisted thoracoscopic interruption of the patent ductus arteriosus is feasible in low-weight infants whereas transcatheter endovascular closure of the ductus is usually not possible. We experienced successful outcome for the treatment of patent ductus arteriosus with 2 mm video-assisted thoracoscopic titanium clipping, We believed that this technique is a simple safe and rapid method for closure of the patent arteriosus.

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Vacuum-Assisted Closure Therapy as an Alternative Treatment of Subcutaneous Emphysema

  • Byun, Chun Sung;Choi, Jin Ho;Hwang, Jung Joo;Kim, Do Hyung;Cho, Hyun Min;Seok, June Pill
    • Journal of Chest Surgery
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    • v.46 no.5
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    • pp.383-387
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    • 2013
  • Vacuum-assisted closure therapy is an alternative method for a massive subcutaneous emphysema treatment. It is easily applicable and shows rapid effectiveness in massive subcutaneous emphysema, intractable with chest tube drainage.

Thermal and uplift histories of Mesozoic granites in Southeast Korea: new fission track evidences

  • Shin, Seong-Cheon;Susumu Nishimura
    • The Journal of the Petrological Society of Korea
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    • v.2 no.2
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    • pp.104-121
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    • 1993
  • Fission track (FT) thermochronological analyses on Mesozoic granites provide new information about cooling and uplift histories in Southeast Korea. Twenty-nine new FT sphene, zircon and apatite ages and seven track length measurements are presented for eleven granite samples. Measured mineral ages against assumed closure temperatures yield cooling rates for each sample. Relatively rapid (7-$15^{\circ}C$/Ma) and simple cooling patterns from the middle Cretaceouss (ca. 90-100 Ma) granites are caused mainly by a high thermal contrast between the intruding magma and country rocks at shallow crustal levels (ca. 1-2.5 km-depths). On the contrary, a slow overall cooling (1-$4^{\circ}C$/Ma) of the Triassic to Jurassic granites (ca. 250-200 Ma), emplaced at deep depths (>>9 km), may mainly depend upon very slow denudation of the overlying crust. The uplift history of the Triassic Yeongdeog Pluton in the Yeongyang Subbasin, west of the Yangsan Fault, is characterized by a relatively rapid uplift (~0.4 mm/a) before the total unroofing of the pluton in the earliest Cretaceous (~140 Ma) followed by a subsidence (~0.2mm/a) during the Hayang Group sedimentation. Stability of original FT zircon ages (156 Ma) and complete erasure of apatite ages suggest a range of 3 to 5.5 km for the basin subsidence. Since 120 Ma up to present, the Yeongyang Subbasin has been slowly uplifted (~0.04 mm/a). The FT age patterns of Jurassic granites both from the northeastern wing of the Ryeongnam Massif and from the northern edge of the Pohang-Kampo Block indicate that the two geologic units have been slowly uplifted with a same mean rate (~0.04 mm/a) since early Cretaceous. Estimates of Cenozoic total uplifts since 100 Ma are different: Ryeongnam Massif (~6 km)=Pohang-Kampo Block (~6 km)>Yeongyang Subbasin(~4 km).

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Improvement of fibrosed scar tissue elongation using self-inflatable expander

  • Jung, Gyu-Un;Kim, Jin-Woo;Pang, Eun-Kyoung;Kim, Sun-Jong
    • The Journal of the Korean dental association
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    • v.54 no.7
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    • pp.501-512
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    • 2016
  • We evaluated a self-inflatable osmotic tissue expander for its utility in creating sufficient soft tissue elongation for primary closure after bone grafting. Six patients with alveolar defects who required vertical augmentation of >6 mm before implant placement were enrolled. All had more than three prior surgeries, and flap advancement for primary coverage was restricted by severely fibrosed scars. Expanders were inserted beneath the flap and fixed with a screw. After 4 weeks, expander removal and bone grafting were performed simultaneously. A vertical block autograft and guided bone regeneration and distraction osteogenesis were performed. Expansion was sufficient to cover the grafted area without additional periosteal incision. Complications included mucosal perforation and displacement of the expander. All augmentation procedures healed uneventfully and the osseous implants were successfully placed. The tissue expander may facilitate primary closure by increasing soft tissue volume. In our experience, this device is effective, rapid, and minimally invasive, especially in fibrous scar tissue.

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Effects of ascorbic acid augmented albumin platelet-rich fibrin on the wound healing activity of human gingival fibroblasts: an in vitro trial

  • Manjiri Kulkarni;Sowmya NK;Gayathri GV;Triveni MG
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.50 no.4
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    • pp.206-215
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    • 2024
  • Objectives: The current in vitro study aimed to assess the effects of ascorbic acid augmented albumin platelet-rich fibrin (AA Alb-PRF) on the wound healing activity of human gingival fibroblasts (HGFs) purported to be a regenerative biomaterial in surgical procedures. Materials and Methods: All assays were performed on three HGF groups, group I: complete media; group II: Alb-PRF, and group III: AA Alb-PRF. Alb-PRF was prepared following the protocol by Fujioka-Kobayashi et al. (2021). For preparation of AA Alb-PRF, 2,500 ㎍ AA was added to the blood pre-centrifugation. All groups were subjected to 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay to estimate cell viability and proliferation, scratch assay for migration (0, 4, 12, and 24 hours) and transwell migration assay for chemotactic migration assessment (24 hours). Outcome variables were optical density (OD) for MTT assay, percentage of wound closure in scratch assay, and number of migrated cells in transwell migration assay. One-way ANOVA for MTT and transwell migration assays and two-way ANOVA for scratch assay with Bonferroni correction were performed with significance set at P<0.05. Results: Cell viability and proliferation (OD: 0.684±0.003 and proliferation: 28%) and wound closure (49.92%±1.62% at 4 hours and 61.39%±0.88% at 12 hours) were significantly higher in group III, while group II demonstrated the maximum number of HGFs migrating across the transwell membrane (9.25±2.49) with P<0.05. Conclusion: HGFs demonstrated a significant increase in viability and proliferation along with rapid wound closure in the presence AA Alb-PRF compared to Alb-PRF alone, indicating additional beneficial effects of AA. Thus, AA Alb-PRF potentiates the wound healing activity of HGFs and could be employed in oral, maxillofacial, and periodontal surgeries as a regenerative biomaterial.

The role of rapid tissue expansion in separating xipho-omphalopagus conjoined twins in Vietnam

  • Tran, Thiet Son;Pham, Thi Viet Dung;Ta, Thi Hong Thuy;Vu, Duy Kien;Nguyen, Thanh Liem
    • Archives of Plastic Surgery
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    • v.48 no.4
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    • pp.378-383
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    • 2021
  • Conjoined twins are rare, and each set of conjoined twins has a unique conjoined anatomy. It is necessary to perform separation to increase the chance of patient survival. Tissue expansion is an advanced technique for providing sufficient soft tissue and skin for wound closure. We report the successful application of rapid tissue expansion in 10-month-old xipho-omphalopagus conjoined twins in Vietnam. A tissue expander was placed on the anterior body between the sternum and umbilicus with a baseline of 70 mL sterile saline (0.9% NaCl). The first injection into the tissue expander began on the 6th day after expander insertion, and injections continued every 2 days with approximately 30-70 mL per injection according to the expansion of the skin. The expander reached 335 mL after six injections and within 10 days. In order to prepare for surgical separation, expansion was completed on the 15th day after insertion. The expanded skin area was estimated to be 180 cm2, which was sufficient to cover both patients' skin deficiencies. The twins presented for surgical separation 6 days following the completion of tissue expansion. Both babies were discharged in good health 1 month after separation.

CLINICAL CASES OF NON-SURGICAL PALATAL EXPANSION ON ADULT PATIENTS

  • Kim, Kyung-Ho;Hong, Hee-Sook;Park, Jun-Ho
    • The korean journal of orthodontics
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    • v.25 no.6 s.53
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    • pp.733-746
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    • 1995
  • In narrow maxillary arch, midpalatal suture can be readily opened in growing children with maxillary palatal expansion. In adult patients, narrow maxilla is generally treated surgically because their growth are deemed completed due to their age. However, in patients under 25, midpalatal suture may not be closed. In addition, maxillary expansion may depend upon the closure of other maxillary sutures, which generally remain open at this stage. The present study attempted suture openings with palatal expansion on 5 female patients in their early 20's. The opening was successful in 4 patients, while only one patient showed no suture opening. In all 4 subjects, no discomfort or pain was present during s\expansion, and the successful suture opening was confirmed on occlusal x-rays. Therefore, for those patients with narrow maxilla in their early 20's, rapid palatal expansion or slow palatal expansion may offer a simple and less complicated option which, if successful, may preclude the need for surgery and thereby circumvent the psychological and financial burdens for the patients.

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