• Title/Summary/Keyword: degeneration

Search Result 1,472, Processing Time 0.029 seconds

Design Optimization of Passive Control Devices for Dynamic Stall Control (동적실속 수동제어장치 최적설계)

  • Joo, Wan-Don;Lee, Bo-Sung;Yee, Kwan-Jung;Lee, Dong-Ho
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.33 no.1
    • /
    • pp.11-19
    • /
    • 2005
  • In order to improve dynamic stall characteristics of an oscillating airfoil, optimal design has been performed for fixed nose droop and Gurney flap. Fixed nose droop is known to be very effective to improve pitching moment characteristics but may cause degeneration of aerodynamic lift at the same time. On the other hand, Gurney flap has the opposite characteristics. For fixed nose droop, location and angle are chosen as design variables, while length is defined as design variable for Gurney flap. Higher order response surface methodology and sensitivity based optimal design method are employed to handle highly nonlinear problem such as dynamic stall. Optimal design has been performed so that lift and pitching moment are simultaneously improved. The design results show that aerodynamic characteristics can be remarkably improved through present design approach and the present passive control method is as good as active control method which combines variable nose droop and Gurney flap.

Fine structural studies on changes of fat bodies in Pieris rapae L. and Bombyx mori. L. during metamorphosis (배추흰나비 (Pieris rapae L.)와 누에나방(Bombyx mori L.) 의 변태(變態)에 따른 지방체(脂肪體)의 미세구조(微細構造) 변화(變化)에 관한 연구(硏究))

  • Han, S.S.;Kim, J.H.;Kim, C.W.;Kim, W.K.
    • Applied Microscopy
    • /
    • v.12 no.2
    • /
    • pp.35-44
    • /
    • 1982
  • The fat bodies of cabbage worm (Pieris rapae) and silk worm (Bomyx mori) during metamorphosis was comparatively studied by electron microscope. 1. Cell oranelles: Golgi apparatus were not observed in both species. It is observed that RER of cabbage worms initiate to degenerate in prepupa stage with complete degeneration at adult stage, while that of silk worms shows similar degenerative pattern. However, mitochondria of cabbage worms are transformed into autophagic vacuole from prepupa stage until adult stage whereas those of silk worm shows a decrease in number in prepupa stage but maintains a certain level until adult stage. 2. Storage substance in cell: Lipid droplets in cabbage worms were observed to increase in numbers during larval stage but afterward decrease in number with an enlargement in size. However immediately after their pupal stage, they almost disappear. On the contrary lipid droplets in silk worms show rather increase in number until adult stage. Protein storage granules in bothspecies were arised from autophagic vacuoles(lysosome) . Fat cells of cabbage worm in adult stage turn out to be residual bodies which last until final stage, but those of silk worm rapidly decrease. Glycogen particles in both species reach maximum at last larval instar and thee gradually decrease thereafter. 3. Fat body sheath: The average width of fat body sheath was measured to be $0.2{\mu}m$ and $0.6{\mu}m$ and surface of fat cells adjacent to fat body sheath in silk worm is heavily infolded.

  • PDF

Spermiogenesis in the Korean Greater Horseshoe Bat, Rhinolophus ferrumequinum korai (한국산 관박쥐 (Rhinolophus ferrumequinum korai)에 있어서의 정자변태)

  • Lee, Jung-Hun;Choi, Byung-Jin;Son, Sung-Won
    • Applied Microscopy
    • /
    • v.22 no.2
    • /
    • pp.97-117
    • /
    • 1992
  • In order to study process of spermiogenesis of the Korean greater horseshoe bat, Rhinolophus ferrumequinum korai, the cycle of seminiferous epithelium was examined by the light and electron microscope and the following results were obtained based on the epithelial cell differentiation. 1. Spermiogenesis occurred from early July to mid-Octber, and spermatogenic activity was vigorous from mid-August to late September. Spermatocytes including spermatogonia were found to be degenerated in only July. It is deduced that the degeneration serves as the mechanism to regulate effective use of energy to prepare for mating and hibernating periods, and regulation of breeding cycle. 2. Spermiogenesis of the Korean greater horseshoe bat was divided according to differentiation of the cell structure, into Golgi, cap, acrosome, maturation and spermiation phases; Golgi, cap and spermiation phases were further divided into two steps of early and late phase respectively, and acrosome phase into three steps of early, mid and late phases, and maturation phase has only one step. Hence, the spermiogenesis consists of ten phases. The first research was done in this article on the changes of chromatin with nucleus, the time of appearance and disappearance of chromatin granules, in case of Korean greater horseshoe bat (Rhinolophus ferrumequinum korai). Chromatin granule began to be condensed in late Golgi and the condensation proceeded to form an irregular mass of a electron-dense chromatin in a form of circular cylinder in the center of nucleus at the phase of maturation. Finally, the chromatin condensation proceeded and perfect nucleus of sperm with homogeneous density was formed when the sperm was separated from Sertoli cell. Therefore, appearance and disappearance of chromatin granules occurred in the period of time between late Golgi and maturation phase, The tail of sperm began to develop in early cap phase, Numerous lipid droplets were obseved in the cytoplasm of spermatids during the maturation phase, which seemed to be used as energy source necessary to make mature sperm during spermiogenesis.

  • PDF

Therapeutic Effect of Lycii fructus Extract in Hepatotoxicity Induced by Carbon Tetrachloride (사염화탄소로 유발된 간손상에 대한 구기자 추출물의 치료효과)

  • Cho, Jung Hee;Sin, Ji Soon;Lee, Kwang Joo;Kim, Yun Bae;Kang, Jong Koo;Hwang, Seock Yeon
    • Korean Journal of Clinical Laboratory Science
    • /
    • v.36 no.1
    • /
    • pp.55-63
    • /
    • 2004
  • The hepatotherapeutic effect of the extract of Lycii fructus has been studied in rats against $CCl_4$ induced liver toxicity. The rats were orally treated with $CCl_4$ (corn oil/$CCl_4$ 1:1, $1m{\ell}/kg$) and then $CCl_4$ ($0.5m{\ell}/kg$) administered four times for 2 weeks. The extracts of L. fructus have been administered every day for 2 weeks after the last $CCl_4$ injection. The experimental groups consisted of negative control (G1), positive control ($CCl_4$ alone; G2), extract of L. fructus (50 mg/kg; G3, 100 mg/kg; G4, 200 mg/kg; G5), respectively. There was a significant decrement to G2 on the serum level of aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase in G5. Also, the content of thiobarbituric acid reactive substance, and phosphatidylcholine hydroperxidase, a marker of lipid peroxidation, in the liver were decreased significantly G5 and G4 compared with G2. Although, catalase or superoxide dismutase, antioxidant enzyme, in the liver were decreased significantly too, it would not be a good sign for the liver. In histopathological findings, such a hepatocellular vacuolar degeneration, lobular restructure, cellular infiltration, necrosis, and so on were shown severely in G2. However, G4 and G5 was shown a mild cytoplasmic vacuolation and inflammatory cell. In conclusion, as a protection against cell damage, lipid peroxidation and serum level, it suggested that the extract of Lycii fructus would have been a therapeutic effect of liver injury directly.

  • PDF

Determination of formaldehyde residue and histopathological observation in formalin and neutral-formalin treated Korean rockfish(Sebastes schlegeli) (포르말린과 중성포르말린 약욕한 어류의 Formaldehyde 잔존량 측정과 병리학적 관찰)

  • Cho, Jae-Kwon;Yang, Han-Choon
    • Journal of fish pathology
    • /
    • v.9 no.2
    • /
    • pp.157-168
    • /
    • 1996
  • In this study, Residue of formaldehyde and histopathological changes in formalin and neutralformalin in treated fish(Sebastes schlegeli) were observed at two different temperatures(15 and $25^{\circ}C$). Immediately after in treatment, residue of formaldehyde in formalin treated fish was show little bit higher than in neutral-formalin treated fish at $15^{\circ}C$. But, there is no difference at water temperature $25^{\circ}C$. The elimination of formaldehyde was markedly temperature-dependent. The approximated withdrawal time were 72hr and 24hr at water temperature 15 and $25^{\circ}C$. Formalin was more toxic than the neutral-formalin at the same condition. Intensity of tissues damage was increased with increasing concentration of chemical and temperature. Formalin and neutral-formalin treatments caused edema and seperation of epithelium, winding of secondary gill lamella, necrosis in the gill ; congestion and pycnosis, vacuolation in the liver ; hydropic and granulated degeneration, necrosis of epithelial cells in the proximal renal tubule ; increasing mucus cells, cracking, necrosis of epidermis and dermis in the skin tissue.

  • PDF

Safety Assessment of Lactobacillus fermentum PL9005, a Potential Probiotic Lactic Acid Bacterium, in Mice

  • PARK JONG-HWAN;LEE YEONHEE;MOON ENPYO;SEOK SEUNG-HYEOK;BAEK MIN-WON;LEE HUI-YOUNG;KIM DONG-JAE;KIM CHANG-HWAN;PARK JAE-HAK
    • Journal of Microbiology and Biotechnology
    • /
    • v.15 no.3
    • /
    • pp.603-608
    • /
    • 2005
  • We recently isolated a novel probiotic strain, Lactobacillus fermentum PL9005 (KCCM-10250), from infant feces and showed that it had a potential immunoenhancing effect. In the present study, a safety assessment of the bacteria was performed using a BALB/c mouse model. Mice were administered with L. fermentum PL9005 daily for 28 days. There were no detectable changes in body weight, feed intake, or clinical signs, and no significant difference in hematological parameters or blood biochemistry between the L. fermentum PL9005-fed and control groups. Bacterial translocation was detected in the mesenteric lymph nodes, liver, and spleen of some mice with and without L. fermentum PL9005 feeding, however, the organisms were not related to ingestion of L. fermentum PL9005; this was confirmed by PCR using a species-specific primer. No gross lesions were detected in the liver, spleen, or intestine of L. fermentum PL9005-fed or control mice. Mucosal thickness in the ileum, cecum, and colon of L. fermentum PL9005-fed mice was not significantly different from that of corresponding organs in control mice. No inflammation or epithelial cell degeneration in the intestines was observed in any mice. These results indicate that ingestion of L. fermentum PL9005 is safe in mice and can be applied in the functional food market.

The Histological Study about the Burn Caused by Moxibustion Using the Commercial Indirect Moxibustion (상용 간접구로 인한 화상에 대한 조직학적 연구)

  • Kwon, O-Sang;Lee, Sang-Hoon;Cho, Sung-Jin;Choi, Kwang-Ho;Yeon, Sun-Hee;Lee, Sae-Bom;Choi, Sun-Mi;Ryu, Youn-Hee
    • Korean Journal of Acupuncture
    • /
    • v.28 no.4
    • /
    • pp.17-28
    • /
    • 2011
  • Objectives : Burn is the important adverse effect of the moxibustion treatment. This research does with the purpose to utilize as basic data which the results of histological observation of the burn tissue which generates when operating various commercial indirect moxa (CIM) on the skin, evaluate the burn because of the surgical operation. Methods : It operated 6 kinds of CIM on the depilated abdomen of the rat. By using the H-E staining and TUNEL assay, the image was observed and analyzed. Results : It could be the moxibustion medical treatment using the CIM generated in the first degree burn until the third degree. And in some case, burn has not generated. By using the H-E stain, the second-degree burn and third degree was observed, and it was observed the first degree burn by using TUNEL assay. In the first degree burn, TUNEL reaction in the epidermal layer was confirmed. The damage to the dermal layer was observed in more than 2 degree burn. In the third degree, the tissue degeneration to the subcutaneous fat was observed but the thickness of the skin tissue was not observed. Conclusions : Basic data classifying the burn generated by the CIM treatment through the histological observation of the burn tissue caused by the CIM treatment were built according to this research result.

The Retrospective Study of 463 Patients who had Funduscopy Examination at Korean Medicine Ophthalmology (한방 안과에 내원하여 안저 검사를 시행한 환자 463명에 대한 후향적 연구 보고)

  • Lee, Ma-Eum;Jeong, Mi-Rae;Kim, Chul-Yun;Kwon, Kang;Seo, Hyung-Sik
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
    • /
    • v.33 no.2
    • /
    • pp.1-11
    • /
    • 2020
  • Objectives : The purpose of this study was to analyze and report status of Korean Medicine Ophthalmology patients who did funduscopy examination. Through this, we hope that the development of our diagnosis and treatment. Methods : From June 1, 2010 to May 31, 2019, Based on the electronic medical records of patients who had funduscopy examination at Korean Medicine Ophthalmology, Busan University Korean Medicine Hospital, the gender, age, visiting motives and paths, diagnosis, examination number of years, other eye examinations and treatments method were summarized and analyzed. Results : 463 patients were able to check the electronic medical records. They were 283 females and 180 males. The mean age of the patients was 51.5 years and elderly patients who 50s and 60s were 49.3% of whole patients. The most common motives for Korean Medicine Ophthalmology visitation was 'combination treatment with other department in Korean Medicine Hospital'. Outer eye diseases were 283 cases, inner eye diseases were 198 cases. Dry eye syndrome, asthenopia, visual discomfort, conjunctivitis, and eye discomfort were most common in the outer eye diseases. Cataracts, Vitreous floater, Macular Degeneration, Glaucoma and Ocular Pain were most common in the inner eye disease. The most common parts of outer eye diseases were Conjunctival, lacrimal gland, paralytic, corneal, eyelid and front uveal, scleral disease and then in inner eye diseases parts, Retinal, lens, vitreous, glaucoma, optic nerve, behind uveal, choroid disease were most common. The number of funduscopy examination was ups and downs. Herbal medicine was the most common used. Conclusions : The funduscopy examination is essential for diagnosis and treatment of eye disease. We hope that the use of fundus examination and other ophthalmologic examination will be expanded soon in Korean Medicine Ophthalmology.

Antioxidant Effect and Liver Protection Effect of Spatholobi Caulis Water Extract (계혈등 물추출물의 항산화 및 간보호효과)

  • Lee, Jae-Jun;Choi, Hong-Sik;Kim, Seung-Mo
    • The Korea Journal of Herbology
    • /
    • v.26 no.3
    • /
    • pp.47-56
    • /
    • 2011
  • Objectives : This study investigated whether the water extract of Spatholobi Caulis (SCE) has the ability to protect hepatocyte against oxidative stress induced by tert-butylhydroperoxide (tBHP) in vitro and $CCl_4$ in vivo. Methods : In vitro, HepG2 cells pre-treated with Spatholobi Caulis water extract (1, 3, 10, $30{\mu}g$/ml) for 12h and further incubated with tBHP ($100{\mu}M$) for the next 12h. Cell viability was assessed by MTT assay. In vivo, rats were orally administrated with the aqueous extract of Spatholobi Caulis (SCE; 50, 100 mg/kg) for 4 days and then, injected with $CCl_4$ 1 mg/kg body weight to induce acute liver damage. Results : Treatment with SCE inhibited cell death induced by tBHP, as evidenced by alterations in the levels of the proteins associated with apoptosis:SCE prevented a decrease in $Bcl_2$, and cleavage of poly(ADP-ribose)polymerase and pro-caspase-3. Moreover, SCE inhibited the ability of tBHP to generate $H_2O_2$ production, thereby restoring GSH content. Moreover, SCE treatments in rats effectively decreased liver injuries induced by a single dose of $CCl_4$, as evidenced by decreases in hepatic degeneration and inflammation as well as plasma alanine aminotransferase and lactate dehydrogenase activities. Consistently, treatments of SCE also protected liver in rats stimulated by $CCl_4$, as indicated by restoration GSH and prevention of MDA in the liver. Conclusions : SCE has the ability 1) to protect hepatocyte against oxidative stress induced by tBHP and 2) to prevent $CCl_4$-inducible acute liver toxicity. Present findings may be informative not only in elucidating the pharmacological mechanism of Spatholobi Caulis, but in determining its potential application for oxidative cellular damage in the liver.

Effect of Popcorn, Wolbachia Variant, on Development and Reproduction in Drosophila melanogaster (Wolbachia 변이종 Popcorn이 초파리의 발육과 생식에 미치는 영향)

  • 한상미;민경태;한명세;이상철
    • Korean journal of applied entomology
    • /
    • v.39 no.3
    • /
    • pp.193-197
    • /
    • 2000
  • Wolbachia, vertically transmitted bacterial endosymbionts, is known to induce cytoplasmic incompatibility (CI), parthenogenesis, or feminization in some insect species. The Wolbachia found to exist symbiotically as a non-virulent form in Drosophila melanogaster, however popcorn is a lethal strain of Wolbachia, which causes tissue degeneration and early death of its adult host. Popcorn-infected flies showed the delayed duration of an egg and larvae, and their pupal period and life span reduced. The oviposition and egg-hatching rate of popcorn-infected flies were decreased 15% and 80%, respectiv~ly, compared to those of the normal Wolbachia-infected flies. The pupation and emergence rates of popcorn-infected flies were 67% and 65%, respectively. When popcorn-infected flies were crossed with Wolba-chia-infected flies, and vice versa, both crosses resulted in a significant reduction in egg production, egg¬hatching, pupation, and emergence rate, and their progeny revealed the popcorn syndrome. When popcorn-infected male flies were crossed with uninfected females, popcorn was not detected in their progeny. Popcorn also maternally transmitted in flies, but it did not induce CI and affected on its host life cycle as a virulence.

  • PDF