• Title/Summary/Keyword: re-expansion

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Expression of NAC transcription factor is altered under intermittent drought stress and re-watered conditions in Hevea brasiliensis

  • Luke, Lisha P.;Sathik, M.B. Mohamed;Thomas, Molly;Kuruvilla, Linu;Sumesh, K.V.
    • Journal of Plant Biotechnology
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    • v.44 no.2
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    • pp.142-148
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    • 2017
  • Drought stress is one of the important factors that restrict the expansion of Hevea brasiliensis cultivation to non-traditional regions experiencing extreme weather conditions. Plants respond to drought stress by triggering expression of several drought responsive genes including transcription factors which in turn trigger expression of various downstream signalling pathways and adaptive networks. Expression of such drought responsive genes may revert back to their original level upon re-watering. However, no reports are available on such phenomenon in Hevea and hence, this study was initiated. For this purpose, NAC transcription factor (NAC tf) was chosen as candidate gene. Its expression levels were monitored under intermittent drought as well as irrigated conditions in two clones (RRII 105 and RRIM 600) of H. brasiliensis with contrasting tolerance level. Copy number of NAC tf was found similar in both the clones. Expression of NAC tf was found highly up-regulated in RRIM 600 (a relatively drought tolerant clone) than in RRII 105 (a relatively drought susceptible clone) throughout the drought incidences which upon re-watering, reached back to its original levels in both the clones. The study indicated the existence of an association between expression of NAC tf and drought tolerance trait exhibited by the tolerant clone RRIM 600. The study also proves the influence of drought and re-watering on the leaf photosynthesis and expression of NAC tf in H. brasiliensis.

A study on Production of Al Foam by Using of Al Return Scrap for Sound and Vibration Absorption Materials

  • Hur, Bo-Young;Kim, Sang-Youl;Park, Dae-Chol;Jeon, Sung-Hwan;Park, Chan-Ho;Yoon, Ik-Sub
    • Proceedings of the IEEK Conference
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    • 2001.10a
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    • pp.198-201
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    • 2001
  • Porous structures of aluminum foam have been studied by using return aluminum scrap. The apparent foam shape, foam height, density, pore size and their distributions in various section areas of the experimental samples have been investigated. The sample have been cast into metallic mold, using aluminum foam prepared from a precursor based on pure Al ingot and return aluminum scrap mixed with various amounts of 1-2wt% increasing viscosity and foam agent materials. The process provides for flexibility in design of foam structures via relatively easy control over the amount of hydrogen evolution and the drainage processes which occur during foam formation. This is facilitated by manipulating parameters such as the foaming agent, thermal histories during solidification and mix melt viscosities. A metal for producing the foamed are decomposing a foaming agent in a molten metal such that there is an initial and a subsequent expansion due to foaming agent. It has been found that the Al porous foaming with variation amount of 1∼2wt% foam agent and at 2min holding time, which melting temperature has appeared homogeneous pore size at 650∼700$^{\circ}C$. The compression strength were 10-13 kg/min at 125ppi, and increased by higher pore density. The acoustical performance of the panel made with the foamed aluminum is considerably improved; its absorption coefficient shows NRC 0.6-0.8. It has been found that the Al foam is very preferable for the compactness of the thermal system.

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Cryopreservation of Bovine IVM/IVF/IVC Blastocysts by Vitrification (체외성숙, 체외수정 및 체외배양에서 생산된 소 배반포기배의 초자화 동결)

  • Nam, H.K.;Kim, E.Y.;Lee, K.S.;Yoon, S.H.;Park, S.P.;Lim, J.H.
    • Clinical and Experimental Reproductive Medicine
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    • v.26 no.2
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    • pp.231-238
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    • 1999
  • The objective of this study was to examine the effect of developmental stage and embryo age of in vitro produced bovine blastocysts after vitrification and thawing. In vitro cultured day 8 blastocysts after IVF were equilibrated 20% ethylene glycol (EG) for 3 min. and were vitrified using EFS40, which is consisted of 40% EG, 18% ficoll, 0.3M sucrose and 10% FBS added in mDPBS for 30 sec. before being plunged into $LN_2$. Also, survival in vitro was assessed by re-expansion and hatching or hatched at 24 hand 48 h postwarming, respectively. The results obtained in these experiments were summarized as follows; 1) When the embryos were cultured for 8 day after IVF, 41.0% of the cleaved embryos developed to the blastocysts (early; 7.6%, expanded; 22.9%, hatching; 4.6% and hatched; 5.9%). 2) When the embryos were exposed or vitrified to the freezing solution, the re-expansion of vitrified embryos (73.3%) was significantly lower than that of control and exposed embryos (100, 97.0%) (p<0.05). But the formation rate of hatching or hatched blastocysts of vitrified embryos (66.7, 46.7%) at 48h after thawing was similar to that of exposed embryos (66.7, 39.4%) but not control (100, 100%) (p<0.01). However, in the total cell numbers of those developed hatched blastocysts, there were not significantly different among the treatment groups. 3) When the embryo survival rates by different developmental stage were examined, the re-expansion was not different among the groups $(64.5{\sim}75.6%)$. After warming 48 h, the hatching and hatched formation of early blastocysts (25.8, 9.7%) was significantly lower than those of expanded (69.7, 39.4%) and hatching blastocysts (53.3, 43.3%) (p<0.05). 4) In addition, when the expanded blastocysts at day 7, 8 and 9 were vitrified, the re-expansion of day 8 and 9 embryos was significantly lower than that of day 7 (day 7; 93.9%, day 8; 75.8% and day 9; 87.5%) (p<0.05). However, the rates of development to hatched blastocysts were no difference among the groups (day 7; 36.4%, day 8; 36.4% and day 9; 31.3%). These results suggested that in vitro produced expanded or hatching blastocysts can be efficiently cryopreserved by the two-step vitrification method using EFS40.

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Improvement Plans for Working Area of Cadastral Surveyors (지적측량수행자의 업무영역 개선방안에 관한 연구)

  • Hong, Sung-Eon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.1
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    • pp.237-242
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    • 2014
  • This study is to analyze open work status and conditions of cadastral surveyors and suggest improvement plans for working area of cadastral surveyors. The results are as below. Based on the analysis, this study suggests expansion of confirmation surveying for cadastral target range, ease of confirmation surveying standard for cadastral, and broader participation opportunities for cadastral surveyors in the cadastral re-survey project as improvement plans. If the Ministry of Land, Infrastructure, and Transport seeks legislative and policy improvement that can create more rational and ideal cadastral surveying conditions based on various reviews on improvement plans for working area of cadastral surveyors in this study will promote symbiotic development among cadastral surveyors.

Effects of Atelectasis on Surface Activity of lung in Rabbits (무기폐(無氣肺)가 폐표면활성도(肺表面活性度)에 미치는 영향에 관(關)한 실험적(實驗的) 연구(硏究))

  • Woo, Jong Soo;Cho, Kwang Hyun;Kim, Jong Won;Sohn, Mal Hyun;Sihn, Kun Soo;Kim, Jin Shik
    • Journal of Chest Surgery
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    • v.9 no.2
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    • pp.109-116
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    • 1976
  • The effects of atelectasis on surface activity of lung extracts were examined in rabbits. Experimental atelectasis was produced in rabbits by artificial pneumothorax and surface tension properties were measured on saline extracts of lung 24 hrs, 48 hrs, one week and four weeks after the induction of pneumothorax. The results were as follows; 1) The minimum surface tension of excised lung extracts 24 hrs after pneumothorax was significantly increased to 28.3 0.41 dynes/cm, and the stability index was significantly decreased to 0.30 from normal value of 0. 87. 2) In the group which was re-expanded 24 hours, later from pneumothorax the surface activity was returned to almost normal range 24 hrs after reexpansion of collapsed lung, 3) When the atelectasis was continued by mechanical means, the extracts of atelectatic lung showed progressive decrease in surface activity, but it was found that surface activity returned to normal level after four weeks even the presence of atelectasis. 4) These observations suggest to us that atelectasis per se does not cause an increase in surface tension of lung extracts, and even in prolonged atelectasis the re-expansion of collapsed lung may be possible when the mechanical cause of atelectasis was excluded.

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A Facial Chuna Manual Therapy for Peripheral Facial Nerve Palsy

  • Park, Yu-Kyeong;Lee, Cho In;Lee, Jung Hee;Lee, Hyun-Jong;Lee, Yun-kyu;Seo, Jung-Chul;Kim, Jae Soo
    • Journal of Acupuncture Research
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    • v.36 no.4
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    • pp.197-203
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    • 2019
  • The purpose of this study was to investigate useful manual therapy techniques for peripheral facial nerve palsy and to propose guidelines to be applied for current manual therapy techniques. Several databases were searched to find manual therapies for facial palsy. These therapies included cervical, and temporomandibular joint chuna manual therapy, proprioceptive neuromuscular facilitation, neuromuscular re-education, facial exercise, and mime therapy. Both cervical, and temporomandibular joint chuna manual therapy release nerve compression, helping blood circulation and nerve conduction. Proprioceptive neuromuscular facilitation uses irradiation, bilateral activation, and eccentric facilitation to improve muscle power and symmetry. Neuromuscular re-education, as a retraining tool for facial movement patterns, enhances neuromuscular feedback. Facial exercise helps the patient continuously move and massage facial muscle themselves. Mime therapy aims to develop a conscious connection between the use of certain muscles and facial expressions. The use of facial chuna manual therapy for peripheral facial nerve palsy can stimulate the proprioceptive neuromuscular receptors in the face. Peripheral facial nerve palsy has 4 phases; progress phase, plateau phase, recovery phase, and sequelae phase. Each phase needs different treatments which include relaxation, assistance, resistance, origin-insertion extension, and nerve pathway expansion.

Numerical Simulation of the Water Temperature in the Al-Zour Area of Kuwait

  • Lee, Myung Eun;Kim, Gunwoo
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.25 no.3
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    • pp.334-343
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    • 2019
  • The Al-Zour coastal area, located in southern Kuwait, is a region of concentrated industrial water use, seawater intake, and the outfall of existing power plants. The Al-Zour LNG import facility project is ongoing and there are two issues regarding the seawater temperature in this area that must be considered: variations in water temperature under local meteorology and an increase in water temperature due to the expansion of the thermal discharge of expanded power plant. MIKE 3 model was applied to simulate the water temperature from June to July, based on re-analysis data from the European Centre for Medium-Range Weather Forecasts (ECMWF) and the thermal discharge input from adjacent power plants. The annual water temperatures of two candidate locations of the seawater intake for the Al-Zour LNG re-gasification facility were measured in 2017 and compared to the numerical results. It was determined that the daily seawater temperature is mainly affected by thermal plume dispersion oscillating with the phase of the tidal currents. The regional meteorological conditions such as air temperature and tidal currents, also contributed a great deal to the prediction of seawater temperature.

DIFFUSIVE SHOCK ACCELERATION BY MULTIPLE WEAK SHOCKS

  • Kang, Hyesung
    • Journal of The Korean Astronomical Society
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    • v.54 no.3
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    • pp.103-112
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    • 2021
  • The intracluster medium (ICM) is expected to experience on average about three passages of weak shocks with low sonic Mach numbers, M ≲ 3, during the formation of galaxy clusters. Both protons and electrons could be accelerated to become high energy cosmic rays (CRs) at such ICM shocks via diffusive shock acceleration (DSA). We examine the effects of DSA by multiple shocks on the spectrum of accelerated CRs by including in situ injection/acceleration at each shock, followed by repeated re-acceleration at successive shocks in the test-particle regime. For simplicity, the accelerated particles are assumed to undergo adiabatic decompression without energy loss and escape from the system, before they encounter subsequent shocks. We show that in general the CR spectrum is flattened by multiple shock passages, compared to a single episode of DSA, and that the acceleration efficiency increases with successive shock passages. However, the decompression due to the expansion of shocks into the cluster outskirts may reduce the amplification and flattening of the CR spectrum by multiple shock passages. The final CR spectrum behind the last shock is determined by the accumulated effects of repeated re-acceleration by all previous shocks, but it is relatively insensitive to the ordering of the shock Mach numbers. Thus multiple passages of shocks may cause the slope of the CR spectrum to deviate from the canonical DSA power-law slope of the current shock.

Rethinking images of Korean dance Colors and Cultural Philosophical Representations in Space (한국춤의 색과 공간에서의 문화철학적 표상에 관한 이미지 재고)

  • Kim, Ji-Won
    • (The) Research of the performance art and culture
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    • no.41
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    • pp.157-186
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    • 2020
  • It illuminates the representation of Korean dance in the sense of color. The unique color and light of Korean dance reflects the essence of Korean art and the consciousness of Koreans. Therefore, analyzing Korean art, colors and meanings can provide the principle of aesthetic interpretation to re-examine Korean colors. This means that it is necessary to pay attention to the possibility of developing original contents as a humanistic basis, asking the origin of Korean art. The Korean thought and philosophy in which color and life become cultures remain the roots for another re-creating vision of Korean art. Therefore, it is time to establish a system of Korean identity as an art with the expansion of various interpretations of various aesthetic attitudes that recognize Korean dance.

SiAlON Bulk Glasses and Their Role in Silicon Nitride Grain Boundaries: Composition-Structure-Property Relationships

  • Hampshire, Stuart;Pomeroy, Michael J.
    • Journal of the Korean Ceramic Society
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    • v.49 no.4
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    • pp.301-307
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    • 2012
  • SiAlON glasses are silicates or alumino-silicates, containing Mg, Ca, Y or rare earth (RE) ions as modifiers, in which nitrogen atoms substitute for oxygen atoms in the glass network. These glasses are found as intergranular films and at triple point junctions in silicon nitride ceramics and these grain boundary phases affect their fracture behaviour. This paper provides an overview of the preparation of M-SiAlON glasses and outlines the effects of composition on properties. As nitrogen substitutes for oxygen in SiAlON glasses, increases are observed in glass transition temperatures, viscosities, elastic moduli and microhardness. These property changes are compared with known effects of grain boundary glass chemistry in silicon nitride ceramics. Oxide sintering additives provide conditions for liquid phase sintering, reacting with surface silica on the $Si_3N_4$ particles and some of the nitride to form SiAlON liquid phases which on cooling remain as intergranular glasses. Thermal expansion mismatch between the grain boundary glass and the silicon nitride causes residual stresses in the material which can be determined from bulk SiAlON glass properties. The tensile residual stresses in the glass phase increase with increasing Y:Al ratio and this correlates with increasing fracture toughness as a result of easier debonding at the glass/${\beta}-Si_3N_4$ interface.