• Title/Summary/Keyword: capillary density

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A Screening Method on Resistance of Tobacco Plants to Bacterial Wilt (세균성마름병에 대한 담배의 저항성검정 방법)

  • 이영근
    • Journal of the Korean Society of Tobacco Science
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    • v.24 no.1
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    • pp.27-31
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    • 2002
  • Three kinds of inoculation methods, capillary, root cutting and dipping were compared for an efficient way to screening the resistant tobacco variety against bacterial wilt, Ralstonia solanacearum. The pricking a capillary tube contained the pathogenic bacterial suspension(10$^{7}$ cfu/$m\ell$) to an axillary bud of each tobacco plant showed different resistance well between varieties. The less period was required in inoculating work and in disease development for the inoculation method used with capillary tube than for two other inoculation methods tested also.

The Effects of Oil on Refrigerant Flow through Capillary Tubes (냉동기유가 모세관내의 냉매유량에 미치는 영향)

  • 홍기수;황일남;민만기
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.12 no.9
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    • pp.791-801
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    • 2000
  • An experimental study was conducted to analyze the effects of oil on refrigerant flow through adiabatic capillary tubes, and to develop a model for mass flow rates of refrigerant/oil mixture at various capillary tubes and flow conditions. Mass flow rates and the profiles of the pressures and temperatures along the capillary tubes was obtained with the oil concentration of R-22/SUNISO 4GS oil mixture at various test conditions. The flow trends as a function of geometry and flow conditions for pure refrigerant and refrigerant/oil mixture were similar in adiabatic capillary tubes. Mass flow rate of the refrigerant/oil mixture was less than that of pure refrigerant at the same test conditions.

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EARLY IRRADIATION EFFECTS ON THE ULTRASTRUCTURE OF THE CAPILLARY ENDOTHELIAL CELL IN THE RAT SUBMANDIBULAR GLANDS (방사선조사에 따른 백서 악하선내 혈관 내피세포 미세구조의 조기변화)

  • Ryu Jung-Soo;Sohn Jaong-Ick;Baa Yong-Chul;Choi Karp-Shik
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.25 no.1
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    • pp.71-87
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    • 1995
  • The purpose of this study was to investigate the early irradiation changes on the ultrastructure of the capillary endothelial cell in the rat submandibular glands. For the study, 110 Sprague-Dawley strain male rats were singly irradiated to their neck regions with the doses of 2Gy, 5Gy, and 10Gy by 6MV X -irradiation, and sacrificed on the 3 hours, 6 hours, 12 hours, 1 day, 3 days, 7 days, and 14 days after irradiation. The authors observed the histologic and ultrastructural changes of the capillary endothelial cell using the light and electron microscopes. The results were as follows: I. In the light microscopic examination, the capillary dilation was observed on the 6 hours group and the capillary density was slightly increased on the 12 hours group after 2Gy and 5Gy irradiation. And luminal size and capillary density were decreased on the 3 days and the 7 days groups after irradiation, after then, they were recovered. But capillary density was still decreased on the 14 days group after 10Gy irradiation. 2. In the transmission electron microscopic examination, the mild proliferation of cytoplasmic process of the endothelial cell and reduction in luminal size were observed on the 3 hours group after irradiation. After then, endothelial swelling, marked proliferation of cytoplasmic process, thickened basal lamina, and numerous pinocytotic vesicles were observed after the 1 day group after irradiation. Thickened basal lamina and numerous pinocytotic vesicles were still observed until the 7 days group after irradiation. These changes were recovered to normal on the 14 days group after 2Gy and 5Gy irradiation, but not after 10Gy irradiation. 3. In the scanning electron microscopic examination, the dilation of conduits and constriction, and meandering were observed on the 1 day group after 10Gy irradiation. These changes were observed with increased coarseness of the surface of the vascular resin casting on the 3 days group after irradiation. 4. From the above results, endothelial swelling, proliferation of cytoplasmic process, and thickening of the basal lamina appeared before the 6 hours group after irradiation. And these changes may also induce the increase of the capillary number and luminal size, after then, capillary permeability was increased via the increase of the number of pinocytotic vesicles. The changes were observed earlier and more apparent with the increase of the irradiation doses under the dose of 10Gy irradiation.

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PvT measruement method of polymer using capillary rheometer (캐필러리 레오미터를 이용한 고분자의 PvT 측정 방법)

  • Kim, Sun-Kyoung;Park, Jae-Un
    • Design & Manufacturing
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    • v.14 no.3
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    • pp.31-36
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    • 2020
  • In injection molding processes, the property of molten resin should be characterized accurately. Among several properties, the PvT state is the most important one, since it affects the shrinkage, warpage, molded weight, and the part density. Thus, the PvT data is crucial to the simulation of the injection molding process. This work shows how such a measurement can be performed for a semi-crystalline and amorphous polymers. The PvT measurement has been conducted using a capillary rheometer using a suitable accessory that blocks the capillary. The results have shown that the PvT data can be obtained using such a rheometer and then the PvT coefficients of the Tait equation can be reached.

AN EXPERIMENTAL STUDY OF THE IRRADIATION EFFECTS ON THE CAPILLARY AND ENDOTHEILIAL CELL OF THE RAT SUBMANDIBULAR GLAND (방사선조사가 악하선 미세혈관과 내피세포에 미치는 영향에 관한 실험적 연구)

  • Yoo Young-Ah;Sohn Jeong-Ick;Choi Mi;Bae Yong-Chul;Choi Karp-Shik
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.24 no.1
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    • pp.67-77
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    • 1994
  • The purpose of this study was to investigate the irradiatiion effects on the capillary and endothelial cell in the submandibular gland. Sprague-Dawley strain male rats were singly irradiated to their neck region with the dose of 5Gy by 6MV X-irradiation and sacrificed on the 6 hours, 12 hours, 1, 3, 7, and 14days after irradiation. The authors observed the histological changes of the capillary at H & E and PAS staining under a light microscope, and also observed the ultrastructural changes of the endothelial cell using a transmission electron microscope. The obtaining results were as follows: 1. In the light microscopic examination, the capillary density was slightly increased on the 1day after irradiation, and increased until the 7 days after irradiatiion. After then, capillary density was apparently decreased. 2. The reaction to PAS staining at acinar cells was decreased on the 6 hours after irradiation, and recovered on the 7days after irradiation. But reaction was decreased on the 14days after irradiation agan, after then, gradually recovered with days. 3. In the transmission electron microscopic examination, mild proliferation of cytoplasmic process of the endothelial cell and reduction in luminal size were observed just after irradiation. After then, nuclear degeneration, marked proliferation of cytoplasmic process, thickened basal lamina, and numerous cytoplasmic vesicles were observed on the 1day after irradiation. These changes were recovered to normal on the 14days after 5Gy group, but not with 10Gy irradiation group. And destruction of endothelial cell and loss of basal lamina were not observed in both groups. 4. From the above results, reduction in luminal size, proliferation of cytoplasmic process and thickening of basal lamina were observed as the irradiation effects on the capillary and endothelial cell of the submandibular gland. And also, these changes may induce increase in capillary number and endothelial permeability by means of increase of cytoplasmic vesicle formation. The changes appeared earlier and more prominent in 10Gy irradiated group than in 5Gy irradiated group.

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Impaired angiogenesis in the enalapril-treated neonatal rat kidney

  • Yim, Hyung Eun;Yoo, Kee Hwan;Bae, Eun Soo;Hong, Young Sook;Lee, Joo Won
    • Clinical and Experimental Pediatrics
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    • v.59 no.1
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    • pp.8-15
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    • 2016
  • Purpose: Nephrogenesis is normally accompanied by a tightly regulated and efficient vascularization. We investigated the effect of angiotensin II inhibition on angiogenesis in the developing rat kidney. Methods: Newborn rat pups were treated with enalapril (30 mg/kg/day) or vehicle (control) for 7 days after birth. Renal histological changes were checked using Hematoxylin & Eosin staining. We also investigated the intrarenal expression of vascular endothelial growth factor (VEGF)-A, VEGF receptor 1 (VEGFR1), VEGFR2, platelet-derived growth factor (PDGF)-B, and PDGF receptor-${\beta}$ with Western blotting and immunohistochemical staining at postnatal day 8. Expression of the endothelial cell marker CD31 was examined to determine glomerular and peritubular capillary density. Results: Enalapril-treated rat kidneys showed disrupted tubules and vessels when compared with the control rat kidneys. In the enalapril-treated group, intrarenal VEGF-A protein expression was significantly higher, whereas VEGFR1 protein expression was lower than that in the control group (P<0.05). The expression of VEGFR2, PDGF-B, and PDGF receptor-${\beta}$ was not different between the 2 groups. The increased capillary CD31 expression on the western blots of enalapril-treated rat kidneys indicated that the total endothelial cell protein level was increased, while the cortical capillary density, assessed using CD31 immunohistochemical staining, was decreased. Conclusion: Impaired VEGF-VEGFR signaling and altered capillary repair may play a role in the deterioration of the kidney vasculature after blocking of angiotensin II during renal development.

Measurement of Electron Temperature and Number Density and Their Effects on Reactive Species Formation in a DC Underwater Capillary Discharge

  • Ahmed, Muhammad Waqar;Rahman, Md. Shahinur;Choi, Sooseok;Shaislamov, Ulugbek;Yang, Jong-Keun;Suresh, Rai;Lee, Heon-Ju
    • Applied Science and Convergence Technology
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    • v.26 no.5
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    • pp.118-128
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    • 2017
  • The scope of this work is to determine and compare the effect of electron temperature ($T_e$) and number density ($N_e$) on the yield rate and concentration of reactive chemical species ($^{\bullet}OH$, $H_2O_2$ and $O_3$) in an argon, air and oxygen injected negative DC (0-4 kV) capillary discharge with water flow(0.1 L/min). The discharge was created between tungsten pin-to pin electrodes (${\Phi}=0.5mm$) separated by a variable distance (1-2 mm) in a quartz capillary tube (2 mm inner diameter, 4 mm outer diameter), with various gas injection rates (100-800 sccm). Optical emission spectroscopy (OES) of the hydrogen Balmer lines was carried out to investigate the line shapes and intensities as functions of the discharge parameters such as the type of gas, gas injection rate and inter electrode gap distances. The intensity ratio method was used to calculate $T_e$ and Stark broadening of Balmer ${\beta}$ lines was adopted to determine $N_e$. The effects of $T_e$ and $N_e$ on the reactive chemical species formation were evaluated and presented. The enhancement in yield rate of reactive chemical species was revealed at the higher electron temperature, higher gas injection rates, higher discharge power and larger inter-electrode gap. The discharge with oxygen injection was the most effective one for increasing the reactive chemical species concentration. The formation of reactive chemical species was shown more directly related to $T_e$ than $N_e$ in a flowing water gas injected negative DC capillary discharge.

The Influence of Paper Stock Type on Characteristics of Sizing (지료조성에 따른 종이의 사이징 특성)

  • Cheong Sang Jin;Kim Bong Yong
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.37 no.2 s.110
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    • pp.11-20
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    • 2005
  • This study was carried out to investigate the influence of paper stock type and heat treatment on sizing effect. Various types of pulps were used to make handsheets sized internally with AKD(alkyl ketene dimer) and externally with CMC(carboxyl methyl cellulose). Most of the handsheets were treated with heat by dry oven $(100^{\circ}C,\;30min)$ to evaluate the effect of heat treatment on sizing development. Internal sizing development of newsprint was very bad, but the effect of heat treatment was much higher than those of NBKP, BCTMP. In case of surface sizing, newsprint was more effective compared to the other pulps. Considering above mentioned results, it seems that internal sizing slows down water into paper by molecular diffusion much more than capillary penetration, but surface sizing slows down capillary penetration. With regard to density, a higher thickness sheets showed high heat treatment effect on sizing, therefore it assumed that heat treatment effect on sizing had very close relationship with sheet density.

Regular Endurance Exercise Decreases Blood Pressure via Enhancement of Angiogenesis and VEGF Expression in Spontaneously Hypertensive Rats (규칙적인 지구성운동이 고혈압쥐 골격근의 혈관생성과 VEGF 발현의 증가를 통한 혈압감소에 미치는 효과)

  • Li, Wei;Park, Hee-Geun;Lee, Young-Ran;Jang, Hak-Young;Choo, Sung-Ho;Lee, Young-Hwa;Gan, Li;Jun, Jong-Kui;Lee, Wang-Lok;Lee, Sang-Ki
    • Journal of Life Science
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    • v.22 no.5
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    • pp.665-670
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    • 2012
  • This study investigated the effect of endurance exercises on blood pressure, angiogenesis, and the vascular endothelial growth factor (VEGF) expression in the skeletal muscle of spontaneously hypertensive rats (SHR). Five week old SHRs and Wistar-Kyoto rats (WKY) were randomly divided into 3 groups: Wistar-Kyoto rats (WKY, n=9), SHR control (SHR-C, n=9), and SHR endurance exercise training (SHR-E, n=9). Endurance exercise training was performed on a treadmill (12-20 m/min, 0% grade, 60 min/day, 5 days/week, 16 weeks). Systolic blood pressure was monitored with the tail-cuff method. The expression of VEGF protein and capillary density were identified using western blotting and H&E staining in the soleus muscle, respectively. Systolic blood pressure was reduced by endurance exercise in SHR ($p$ <0.05). The capillary density of skeletal muscles in SHR-C was lower than in WKY ($p$ <0.05), but it was recovered by endurance exercise training (SHR-E) compared to SHR-C ($p$ <0.05), and VEGF protein was also increased by endurance exercise training compared to SHR-C ($p$ <0.05). These data suggest that the enhancement of capillary density via an increase of VEGF expression in skeletal muscles by endurance exercise training could be an important factor to inhibit blood pressure elevation in SHR.

Effects of Artemisia Capillaris Thunberg on the Plasma and Liver Lipid Metabolism in Rats (사철쑥 (Artemisia Capillaris Thunberg)이 흰쥐 혈액 및 간지질 대사에 미치는 영향)

  • 이형자;황은희
    • Journal of Nutrition and Health
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    • v.35 no.4
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    • pp.421-430
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    • 2002
  • This study was performed to investigate the influence of dietary and extract foods from A. capilliaris Thunberg on plasma and liver lipid metabolism in male Sprague-Dawley rats. For the experiment of liver and plasma lipid metabolism, Rats were find diets containing normal concentrations of fat or high concentrations of lard and two different preparations of A. capillaris Thunberg ; control diet (group C),50 mg/kg body weight A. capillary Thunberg methanol extract (group M), 6 g/kg diet A. capillary Thunberg dried powder (group P), high lard control diet (group L), 50 mg/kg body weight A. capillaris Thunberg with high lard (group LM) and 6 g/kg diet A. capillary Thunberg with hi\ulcorner lard (group LP). Effects of A. capillary Thunberg on plasma total cholesterol. High-density lipoprotein (HDL) cholesterol, Atherogenic index, triglyceride, plasma and liver peroxide contents, fatty acid composition of liver lipid and the distribution of fat droplets of liver. Supplementation of A. capillaris Thunberg resulted in lower plasma cholesterol, atherogenic index and triglyceride, and higher HDL-cholesterol in rats find high lard diets. However, these effects were not observed with low level of fat (groups C, M and P). A shift caused by feeding high lard diets in increased plasma and liver peroxides, saturated fatty arid composition of liver lipid and the more frequent distribution of fat droplets in liver could be reversed by feeding A. capillary Thunberg. This study suggests that A. capillary Thunberg co alter lipid metabolism in plasma and liver.