• 제목/요약/키워드: Pore ring

검색결과 41건 처리시간 0.024초

북양(北洋) 침엽수재(針葉樹材)의 공기(空氣) 투과성(透過性) (Air Permeability of Softwoods Imported from the Russian Far East)

  • 지우근;김규혁
    • Journal of the Korean Wood Science and Technology
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    • 제24권4호
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    • pp.22-31
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    • 1996
  • Air permeabilities for both sapwood and heartwood of the three softwoods(Picea jezoensis, Larix gmelini, Pinus sylvestris), imported from the Russian Far East, in the three different structural directions were measured using steady-state rotameter method. After measuring permeability, the liquid absorption into the longitudinal permeability specimens was measured, and then related with the measured permeability. The longitudinal permeability was overwhelmingly greater than the transverse permeability, with the radial direction showing higher permeability than the tangential direction. There appear to be species differences in permeability of the three softwoods. The mean longitudinal sapwood permeability of P. jezoensis(3.300darcy) and P. sylvestris(3.028darcy) were considerably greater(ca. 25times) than that of L. gmelini(0.134darcy). Also the average longitudinal heartwood permeability of P. jezoensis(0.300darcy) was about 10 times as great as that of P. sylvestris(0.029darcy) and L. gmelini(0.024darcy). The average calculated radius of pit openings in the heartwood was $0.101{\mu}m$ for L. gmelini, $0.152{\mu}m$ for P. sylvestris for and $0.703{\mu}m$ for P. jezoensis. Heartwood permeability increases with the increase in radius of pit pore and the decrease in ring width and in extractive content, even though the correlation between permeability and its affecting factors was dependent on species. However, there was an inverse relationship between specific gravity and permeability, showing poor correlation between them. The correlation between air permeability and liquid retention was fairly high, so it was revealed that prediction of liquid absorption into the wood by using permeability was feasible.

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透膜法에 依한 이온量 및 分子量의 決定에 關한 硏究 (I) 透析裝置 및 實驗方法의 改良 (A Study on the Determination of Ionic and Molecular Weight of Dissolved Substance by Dialysis Method (Ⅰ). Improvements of the Dialysis Apparatus and Its Operations)

  • 신윤경;이전
    • 대한화학회지
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    • 제16권5호
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    • pp.304-313
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    • 1972
  • 溶解된 粒子의 이온量 또는 分子量을 決定하는 方法으로서의 透膜法에는 裝置의 未備點과 實驗方法의 改良되어야 할 點이 아직 남아 있으므로 우선 이들을 改善하여 補完하였다. 透析簡에 膜을 密着시킬수 있도록 鐵製링을 開發하였다. 透析液과 外部液의 水準을 0.02mm의 精度로 一致調節하고 維持시킴으로써 渗透 및 濾過效果를 最小限度로 抑制시켰다. 두 液의 攪拌速度를 任意의 定速度로 變更하여 그 攪拌量을 一定하게 維持할 수 있도록 하였으며, 그 溫度를 透析其間中 ${\pm}0.01^{\circ}C$의 精度로 一致維持시킬수 있도록 하였다. 透析期間中 透析液의 부피變化를 -1.62 ~ +0.92%範圍로 좁혔으며, 渗透 및 濾過效果와 膜孔의 크기와의 關係를 追究하여 最適透析時間을 究明하였다.

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N-Acetyl-D-Glucosamine Kinase Is a Component of Nuclear Speckles and Paraspeckles

  • Sharif, Syeda Ridita;Lee, HyunSook;Islam, Md. Ariful;Seog, Dae-Hyun;Moon, Il Soo
    • Molecules and Cells
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    • 제38권5호
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    • pp.402-408
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    • 2015
  • Protein O-GlcNAcylation, dictated by cellular UDP-N-acetylglucosamine (UDP-GlcNAc) levels, plays a crucial role in posttranslational modifications. The enzyme GlcNAc kinase (NAGK, E.C. 2.7.1.59) catalyzes the formation of GlcNAc-6-phosphate, which is a major substrate for the biosynthesis of UDP-GlcNAc. Recent studies have revealed the expression of NAGK in different types of cells especially in neuronal dendrites. Here, by immunocytochemistry (ICC) and immunonucleochemistry (INC) of cultured rat hippocampal neurons, HEK293T and GT1-7 cells, we have showed that NAGK immuno-reactive punctae being present in the nucleoplasm colocalized with small nuclear ribonucleoprotein-associated protein N (snRNPN) and p54NRB, which are speckle and paraspeckle markers, respectively. Furthermore, NAGK IR cluster was also found to be colocalized with GTF2H5 (general transcription factor IIH, polypeptide 5) immuno reactive punctae. In addition, relative localization to the ring of nuclear lamin matrix and to GlcNAc, which is highly enriched in nuclear pore complexes, showed that NAGK surrounds the nucleus at the cytoplasmic face of the nuclear outer membrane. By in situ proximity ligation assay (PLA) we confirmed the colocalization of NAGK with snRNPN in the nucleus and in dendrites, while we also verified the interactions of NAGK with p54NRB, and with GTF2H5 in the nucleus. These associations between NAGK with speckle, paraspeckle and general transcription factor suggest its regulatory roles in gene expression.

1,3,5-Benzenetricarbonyl Trichloride의 화학적 불안정성과 분리막 성능 (Membrane Performance and Chemical Instability of 1,3,5-Benzenetricarbonyl Trichloride)

  • 박철호;김찬수;심준목;박현설;조윤행
    • 멤브레인
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    • 제30권3호
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    • pp.200-204
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    • 2020
  • 1,3,5-benzenetricarbonyl trichloride는 3개의 아실클로라이드가 벤젠고리 1,3,5에 위치한 화학물질로, 높은 가교도를 통한 물리적·화학적 특성을 요구하는 곳에 사용하는 중요한 화학물이다. 특히 일정 기공크기를 갖고 있는 3차원 구조체 형성이 가능하여, 다양한 분리 정제 분야에 사용되고 있다. 하지만 아실클로라이드의 높은 반응성은 반응속도가 빠른 장점을 갖고 있지만, 다른 측면에서는 일정한 성능을 가질 수 있도록 화학적 제어가 어려운 점도 있다. 따라서 본 연구에서는 1,3,5-benzenetricarbonyl trichloride의 화학적 변화가 어떻게 분리막 성능에 영향을 주는지 관찰하였다.

Evaluation of 20(S)-ginsenoside Rg3 loaded hydrogel for the treatment of perianal ulcer in a rat model

  • Jin, Longhai;Liu, Jinping;Wang, Shu;Zhao, Linxian;Li, Jiannan
    • Journal of Ginseng Research
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    • 제46권6호
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    • pp.771-779
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    • 2022
  • Background: As a kind of common complication of the surgery of perianal diseases, perianal ulcer is known as a nuisance. This study aims to develop a kind of 20(S)-ginsenoside Rg3 (Rg3)-loaded hydrogel to treat perianal ulcers in a rat model. Methods: The copolymers PLGA1600-PEG1000-PLGA1600 were synthesized by ring-opening polymerization process and Rg3-loaded hydrogel was then developed. The perianal ulcer rat model was established to analyze the treatment efficacy of Rg3-loaded hydrogel for ulceration healing for 15 days. The animals were divided into control group, hydrogel group, free Rg3 group, Rg3-loaded hydrogel group, and Lidocaine Gel® group. The residual wound area rate was calculated and the blood concentrations of interleukin-1 (IL-1), interleukin-6 (IL-6), and vascular endothelial growth factor (VEGF) were recorded. Hematoxylin and eosin (H&E) staining, Masson's Trichrome (MT) staining, and tumor necrosis factor α (TNF-α), Ki-67, CD31, ERK1/2, and NF-κB immunohistochemical staining were performed. Results: The biodegradable and biocompatible hydrogel carries a homogenous interactive porous structure with 10 ㎛ pore size and five weeks in vivo degradation time. The loaded Rg3 can be released sustainably. The in vitro cytotoxicity study showed that the hydrogel had no effect on survival rate of murine skin fibroblasts L929. The Rg3-loaded hydrogel can facilitate perianal ulcer healing by inhibiting local and systematic inflammatory responses, swelling the proliferation of nuclear cells, collagen deposition, and vascularization, and activating ERK signal pathway. Conclusion: The Rg3-loaded hydrogel shows the best treatment efficacy of perianal ulcer and may be a candidate for perianal ulcer treatment.

국산목재의 고급가구 및 목공예 용재 개발을 위한 기초연구 - 국내산 밤나무 7품종의 해부 및 물리적 특성- (Fundamental Study of Domestic Wood for the Materials for High-class Furnitures and Woodcrafts -Anatomical & Physical Characteristics of Chestnut Woods Grown in Korea-)

  • 이선화;권성민;박병호;이성재;이욱;김만조;김남훈
    • Journal of the Korean Wood Science and Technology
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    • 제36권6호
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    • pp.23-32
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    • 2008
  • 국내산 목재의 신용도개발을 위한 기초연구로서, 국내에서 생장한 밤나무 7품종(단택, 이취, 이평, 만성, 은기, 유마, 축파)의 목재의 해부 및 물리적 특성을 조사하였다. 밤나무재의 관공은 환공성 문양공재 형태였고 주로 고립관공이 관찰되었다. 방사유세포는 평복, 직립, 방형이 모두 존재하였으나 주로 평복세포였다. 방사조직은 단열, 복열, 다열의 형태가 모두 관찰되었으나 수심부에서는 거의 단열방사조직이었고 수피부에서는 복열이나 다열방사조직의 출현빈도가 높았다. 수심부는 수피부보다 도관직경이 작았고, 단위면적 당 도관의 분포수가 많았으며 방사조직의 수가 적고 방사조직의 세포고가 높았다. 복열 및 다열방사조직의 출현비율은 단택, 이취, 만성, 축파에서 높은 반면, 유마, 은기, 이평에서 낮았다. 연륜폭은 수심부가 수피부에 비해 비교적 더 넓었고, 수심부 연륜폭은 만성과 유마가, 수피부 연륜폭은 이취가 넓었다. 만재율은 수심부와 수피부 간에 큰 차이가 없었으나 대체적으로 수피부가 다소 높았고, 품종 중에서는 만성과 축파가 높았다. 생재함수율은 모든 품종에서 심재부가 변재부보다 다소 높게 나타났다. 밀도는 심재부와 변재부, 품종에 따른 큰 차이는 없었으나 대체적으로 심재가 변재보다 높게 나타났으며 특히 이평과 이취의 밀도가 컸다.

흰쥐 절치치수의 Odontoblast에 관한 Freeze-Fracture 연구 (A Freeze-fracture Study on the Odontoblast of Dental Pulp in the Rat Incisor)

  • 김명국
    • Applied Microscopy
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    • 제16권2호
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    • pp.1-13
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    • 1986
  • The purpose of this study was to investigate the morphology and intercellular junctions of the odontoblast of dental pulp in the rat incisor by means of the freeze fracture electron microscopy. Twenty male Sprague-Dawley rats weighing $150{\sim}200g$ were used. After being anesthetized by an intraperitoneal injection of 0.5 ml sodium pentobarbital per kg in body weight(60 mg/ml) the animals were perfused with 2.5% glutaraldehyde-2% paraformaldehyde fixative in 0.1 M cacodylate buffer, pH 7.2 through the ascending aorta for one hour. The incisors were carefully extracted from the jaws and demineralized by suspending them in 0.1 M EDTA in 3% glutaraldehyde (pH 7.2) for two weeks. After demineralization, the specimens were obtained from the portion divided into five equal parts. For freeze-fracture replication, demineralized tissues were infiltrated for several hours with 10%, 25% glycerol in 0.1M cacodylate buffer as a cryoprotectant and then frozen in liquid Freon 22 and stored in liquid nitrogen. Fracturing and replication were done in Balzers BAF 400D high-vacuum freeze-fracture apparatus at $-120^{\circ}C$ under routine $5X10^{-7}$ Torr vacuum. The tissue was immediately replicated with platinum unidirectionally at $45^{\circ}$ angle and reinforced with carbon at $90^{\circ}$ angle unidirectionally or by using a rotary stage. The replication process was monitored by a quartz-crystal device. The replicas were immersed in 100% methanol overnight. The tissue was then digested from the replica by clorox (laundry bleach), placed into 5% EDTA, and washed repeatedly with distilled water. The replicas were picked up on 0.3% formvar-coated 75 mesh grids and examined in the JEOL 100B electron microscope. The results were as follows; 1. Both in thin sections and freeze-fracture replicas, three types of intercellular junctions were recognizable in the plasma membrane of odontoblast: gap junction, tight junction and desmosome-like junction. 2. The nuclear pores were evenly distributed over the nuclear envelope. The pore complex formed a ring about 70 nm in diameter. 3. Gap junctions were found between odontoblasts as well as odontoblasts and neighbouring pulp cells (fibroblast, subodontoblastic cell process, nerve-like fibre). Gap junctions, which were round, ellipsoid and pear-shaped and 600 nm in diameter, were observed in the odontoblast. 4. Numerous round and ellipsoid gap junctions could be frequently seen on the plasma membranes in cell body and apical part of the odontoblasts. On the P face, the junctions were recognized as a cluster of closely packed particles, measuring about 9 nm in diameter, and on the E face, the junctions were recognized as a shallow grooves.

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이장재의 세포독성에 관한 실험적 연구 (AN EXPERIMENTAL STUDY ON THE CYTOTOXICITY OF CAVITY LINERS)

  • 김정혜;김영해
    • Restorative Dentistry and Endodontics
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    • 제15권2호
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    • pp.77-92
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    • 1990
  • The purpose of this study was to evaluate the cytotoxic effects of 6 cavity liners in vitro. Human fibroblasts were cultured in ${\alpha}$-MEM and each liner was manually mixed and filled in glass ring cylinder ($8{\times}8mm$ in diameter, in height). The cylinders filled with the liners were placed in the center of the dish (35mm in diameter) containing 3ml of ${\alpha}$-MEM. Millipore filters (pore size $0.22{\mu}m$) to simulate dentin barrier were also placed between the bottom of cylinder and the dish. Then the culture dishes were stored in 5% $CO_2$ containing incubator for 5 and 10 days at the temperature of $36.6^{\circ}C$. The results of the experiments were analyzed by counting the cells in the period of 5 and 10 days respectively, and were assessed by calculating the cell multiplication rate and the relative growth rate. The experiemntal groups and the control group were compared statistically. The results of the study were summarized as follows: 1. The cell number of Zinc oxide-eugenol was $(4.13{\pm}1.31){\times}10^4$ cells/ml at 5 days and $(4.32{\pm}1.61){\times}10^4$ cells/ml at 10 days. 2. The cell number of Cavitec was ($8.35{\pm}2.87{\times}10^4$ cells/ml and $(10.08{\pm}5.10){\times}10^4$ cells/ml at 5 and 10 days respectively. 3. The cell number of Dycal was $(13.56{\pm}3.89){\times}10^4$ cells/ml at 5 days and $(34.75{\pm}8.85){\times}10^4$ cells/ml at 10 days. 4. The cell number of life was $(11.46{\pm}3.32){\times}10^4$ cells/ml and $(21.92{\pm}6.18){\times}10^4$ cells/ml at 5 and 10 days. 5. The cell number of Base cement was $(13.73{\pm}3.73){\times}10^4$ cells/ml and $(36.68{\pm}5.20){\times}10^4$ cells/ml at 5 and 10 days. 6. The cell number of Dentin cement was $(13.58{\pm}3.90){\times}10$ cells/ml and $(66.95{\pm}24.09){\times}10$ cells/ml at 5 and 10 days. 7. The cell multiplication rate of zinc oxide-eugenol cements was significantly less than that of the calcium hydroxide and glass ionomer cement. (P < 0.05)

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한국산(韓國産) 개나리속(屬)의 해부학적(解剖學的) 성질(性質)에 관한 연구(硏究) (Studies on Anatomical Properties of Forsythia in Korea)

  • 김재경;홍병화
    • Journal of the Korean Wood Science and Technology
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    • 제12권4호
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    • pp.31-35
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    • 1984
  • 우리 나라 특산(特産) 수종(樹種)인 개나리속(屬)의 해부학적(解剖學的) 성질(性質)을 조사(調査)한 결과(結果)는 다음과 같다. 횡단면상(橫斷面上)의 도관(導管)은 거의 단일도관(單一導管)이었고, 2~3개(個)로 복합(複合)된 복합도관(複合導管)도 가끔 나타나고, 도관(導管)의 배열상태(排列狀態)는 복사공성(輻射孔性) 환공재(環孔材)이었다. 도관(導管)의 평균(平均) 길이는 개나리 $539.98{\pm}154.71{\mu}$, 만리화 $602.22{\pm}157.38{\mu}$, 장수만리화 $465.50{\pm}83.02{\mu}$이었다. 목섬유(木纖維)의 평균(平均) 길이는 개나리 $387.40{\pm}68.23{\mu}$, 만리화 $533.90{\pm}106.77{\mu}$, 장수만리화 $482.40{\pm}72.33{\mu}$ 이었다. 방사조직(放射組織)의 형(型)은 이성공형(異性工型)이었다.

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자연산 조피볼락, Sebastes schlegeli의 소화관에 기생하는 Hysterothylacium sp.와 Anisakis simplex (Nematoda: Anisakidae)의 형태학적 비교 및 숙주의 조직병리학적 반응 (Morphological Comparison Hysterothylacium sp. and Anisakis simplex (Nematoda: Anisakidae) from Wild Black Rockfish, Sebastes schlegeli, and Histopathological Host Reaction)

  • 박정준;박명애;최혜승;김석렬
    • Applied Microscopy
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    • 제41권3호
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    • pp.205-213
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    • 2011
  • 조피볼락, Sebastes schlegeli 소화관 주변에는 다수의 아니사키 스가 기생하고 있었으며, 몇몇 개체들은 간의 표면에 존재하고 있었다. 유전학적 결과 조피볼락에 기생한 아니사키스는 3종으로 분석되었으며, Hysterothylacium sp.가 가장 많이 분포하고 있었다. Hysterothylacium sp.는 Anisakis simplex보다 짧고 가늘었다. 두 종 모두 전방부분에는 lip, 입, 신경환, 분비공, 분비관이 관찰되었다. 두 종 모두 중간부분에는 식도, 위, 장이 존재하고 있었 지만, intestinal ceacum과 ventricular appendage는 Hysterothylacium sp.에서만 관찰되었다. Hysterothylacium sp.의 후방부분 끝에는 conical nodulose apex이 관찰되었지만, A. simplex의 후방부분 끝에는 spine이 관찰되었다. SEM으로 관찰한 결과 Hysterothylacium sp.의 입 주위에는 3개의 lip이 존재하고 있었는데, dorsal lip은 넓이 65 ${\mu}m$ 내외였고, 한쌍의 lateroventral lip은 넓이 60 ${\mu}m$ 내 외였다. Lip의 표면에는 넓이 8 ${\mu}m$ 내외의 유두돌기 한쌍이 존재하고 있었다. Hysterothylacium sp.와 A. simplex의 충체 넓이는 각각 480 ${\mu}m$와 900 ${\mu}m$ 내외로 측정되었다. Hysterothylacium sp. 의 lateral alae는 높이 7 ${\mu}m$ 내외였으며, cornical nodulose apex에 존재하는 돌기는 지름 약 3.3 ${\mu}m$였다. A. simplex의 후방부분 끝 에는 높이 약 20 ${\mu}m$의 spine이 관찰되었다. 조피볼락 장의 내강 에 존재하는 아니사키스들은 대부분 Hysterothylacium sp.였고, 점막주름 근처 혹은 점막하층에 기생하고 있었다. 아니사키스의 기생으로 인하여 숙주의 점막상피에는 다수의 점액세포가 증가하였다.