• 제목/요약/키워드: membrane integrity

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Electrospray를 통한 전도성 박막의 제조 (Preparation of Conductive $TiO_2$ thin film by Electrospray Depositon)

  • 이경화;김한성
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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    • pp.381-382
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    • 2008
  • $TiO_2$ colloidal solution was electrosprayed for preparing a conductive thin film with high quality. Electrospray is a technique of liquid dispersion electrically and a good method of manufacturing nanoparticle, nanofiber, porous membrane, film preparation and coating. Water and ethanol were used as solvents and their mixing ratio was varied for studying the influence of solvent volatile on nanoparticle dispersion. Various nozzles to control the thru-put of solutions.were examined. Integrated analytical method and scanning electron microscope were used to analyze integrity and microscopic images.

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석유수지 비중차를 이용한 고무아스팔트 도막-시트 복합방수의 부착성능 비교 연구 (The Comparative Study on Attached Performance of the Rubber Asphalt Membrane-Sheet Composite Waterproof by Difference of the Specific Gravity of the Petroleum Resin)

  • 윤성환;박완구;김동범;박진상;오상근
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2017년도 추계 학술논문 발표대회
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    • pp.130-131
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    • 2017
  • The combined waterproofing technique, which forms the waterproofing layer of two or more substances, is characterized by forming a waterproof layer, which is characterized by the formation of waterproof layers and the thickness of the waterproofing layer is inherently formed. In this study, it is intended to verify the integrity of the material through the manufacture of materials for special purpose waterproofing methods, primarily for the manufacture of composite waterproofing materials and composite waterproofing methods using cement materials and materials.

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Construction and Characterization of a Burkholderia pseudomallei wzm Deletion Mutant

  • Yuen, Chee-Wah;Ong, Eugene Boon Beng;Mohamad, Suriani;Manaf, Uyub Abdul;Najimudin, Nazalan
    • Journal of Microbiology and Biotechnology
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    • 제22권10호
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    • pp.1336-1342
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    • 2012
  • In Burkholderia pseudomallei, the pathogen that causes melioidosis, the gene cluster encoding the capsular polysaccharide, is located on chromosome 1. Among the 19 capsular genes in this cluster, wzm has not been thoroughly studied. To study the function of wzm, we generated a deletion mutant and compared it with the wild-type strain. The mutant produced less biofilm in minimal media and was more sensitive to desiccation and oxidative stress compared with the wild-type strain, indicating that wzm is involved in biofilm formation and membrane integrity. Scanning electron microscopy showed that the bacterial cells of the mutant strain have more defined surfaces with indentations, whereas cells of the wild-type strain do not.

Exploring Staphylococcus aureus Virulence Factors; Special Emphasis on Staphyloxanthin

  • Yehia, Fatma Al-zahraa A.;Yousef, Nehal;Askoura, Momen
    • 한국미생물·생명공학회지
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    • 제49권4호
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    • pp.467-477
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    • 2021
  • Staphylococcus aureus is a well-known pathogen that can cause diseases in humans. It can cause both mild superficial skin infections and serious deep tissue infections, including pneumonia, osteomyelitis, and infective endocarditis. To establish host infection, S. aureus manages a complex regulatory network to control virulence factor production in both temporal and host locations. Among these virulence factors, staphyloxanthin, a carotenoid pigment, has been shown to play a leading role in S. aureus pathogenesis. In addition, staphyloxanthin provides integrity to the bacterial cell membrane and limits host oxidative defense mechanisms. The overwhelming rise of Staphylococcus resistance to routinely used antibiotics has necessitated the development of novel anti-virulence agents to overcome this resistance. This review presents an overview of the chief virulence determinants in S. aureus. More attention will be paid to staphyloxanthin, which could be a possible target for anti-virulence agents.

Excretory-Secretory Products of Trichomonas vaginalis Cause Apoptosis in Mouse Sperm in Vitro

  • Keum, Jihyun;Roh, Jaesook;Ryu, Jae-Sook;Ryu, Ki-Young
    • Parasites, Hosts and Diseases
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    • 제60권5호
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    • pp.357-360
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    • 2022
  • Excretory-secretory products (ESP) of T. vaginalis have been shown to inhibit sperm motility, viability, and functional integrity, leading to a decreased fertilization rate in vitro. This study investigated whether T. vaginalis induce apoptosis and ultrastructural changes of sperm using flow cytometry and electron microscopy. Incubation of sperm with T. vaginalis ESP increased phosphatidylserine externalization and DNA fragmentation, and decreased mitochondrial membrane potential. Transmission electron microscopy of sperm incubated with ESP revealed abnormal features such as distorted heads, broken necks, and acrosomes exocytosis. This is the first report that demonstrates a direct impact of T. vaginalis ESP on sperm apoptosis and architecture in vitro.

Mass spectrometry-based approaches to explore metabolism regulating ferroptosis

  • Nguyen, Chi Thi Ngoc;Kim, Seon Min;Kang, Yun Pyo
    • BMB Reports
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    • 제55권9호
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    • pp.413-416
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    • 2022
  • Ferroptosis is a type of programmed cell death distinct from apoptosis or necroptosis. Ferroptosis is well characterized by an iron-dependent accumulation of lipid peroxides and disruption of cellular membrane integrity. Many metabolic alterations can prevent or accelerate ferroptosis induction. Recent advances in analytical techniques of mass spectrometry have allowed high-throughput analysis of metabolites known to be critical for understanding ferroptosis regulatory metabolism. In this review, we introduce mass spectrometry-based analytical methods contributing to recent discovery of various metabolic pathways regulating ferroptosis, focusing on cysteine metabolism, antioxidant metabolism, and poly-unsaturated fatty acid metabolism.

Effect of Extenders and Temperatures on Sperm Viability and Fertilizing Capacity of Harbin White Boar Semen during Long-term Liquid Storage

  • Zhou, J.B.;Yue, K.Z.;Luo, M.J.;Chang, Z.L.;Liang, H.;Wang, Z.Y.;Tan, J.H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제17권11호
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    • pp.1501-1508
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    • 2004
  • In this study the effect of extenders and temperatures on sperm viability and fertilizing capacity of boar sperm during long-term storage was investigated. Acrosomal integrity, membrane integrity, motility and hypo-osmotic resistance were evaluated by fluorescence and light microscopy. An in vitro fertilization test was performed to assess the fertilizing capacity of stored spermatozoa. The five diluents tested were ranked according to their ability to maintain sperm functional parameters and Zorlesco (ZO) extender with BSA or with PVA instead of BSA produced the best results. Zorlesco extender substituted with PVA (ZO+PVA) was found to maintain motility both at 15 and 20$^{\circ}C$. within 5 days of storage, but the quality of semen stored at 15$^{\circ}C$ decreased thereafter as compared to semen stored at 20$^{\circ}C$ Semen stored at 5$^{\circ}C$ demonstrated rapid loss of motility already within 24 h. Both fertilization and cleavage of semen stored at 20$^{\circ}C$ in ZO substituted with PVA instead of BSA did not change significantly until day 8 of storage. It is therefore concluded that PVA can be used to substitute for BSA and 20$^{\circ}C$ was more suitable than 15$^{\circ}C$ for boar semen storage, and in vitro fertilizing capacity of spermatozoa was maintained for at least 8 days in ZO+PVA at 20$^{\circ}C$.

다차원 네트워킹을 적용한 선박 블랙박스에서 Forensic자료 생성 (Multidimensional Networking Application of Ship Black Box and Forensic Data Extraction)

  • 박대우
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2009년도 추계학술대회
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    • pp.387-390
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    • 2009
  • 선박제조에서 Ubiquitous-IT Convergence를 적용한 디지털 장치들은 선박 자동화 장치로서 사용되고 있다. 선박의 화재 등 재난의 책임 소재를 가리는 법적인 증거자료로서 무결성과 연속성을 갖춘 선박 블랙박스의 항해자료기록이 필요하다. 본 논문에서는 선박에서 사용되는 근거리 RFID 센서와의 Zigbee 무선 근거리 통신과 Wireless LAN, UWB 통신, GPS와 인공위성을 이용한 다차원 네트워크를 이용하여 선박 블랙박스로부터 Forensic자료를 생성하는 연구이다. 블랙박스에 기록되는 선박의 항해 기록은 3DES 1024bit로 암호화하여 인공위성을 통해 전송되며, SHA-1 해시 함수를 이용하여 선박보험사와 선박관리기록청에 실시간으로 2중으로 저장하여 Forensic자료로서 연속성과 무결성을 확보한다.

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Letrozole, an aromatase inhibitor, improves seminal parameters and hormonal profile in aged endangered Markhoz bucks

  • Rezaei, Ako;Vaziry, Asaad;Farshad, Abbas
    • Animal Bioscience
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    • 제35권11호
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    • pp.1666-1674
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    • 2022
  • Objective: Letrozole, a potent aromatase inhibitor, is known to have the potential to modify male reproductive function by altering sex hormone levels. This study aimed to evaluate the semen and testicular characteristics and hormonal profile of aged Mrakhoz bucks (Capra hircus) treated with letrozole. Methods: Twelve Markhoz male goats, aged between 4.5 to 5.5 years with an average body weight (BW) of 61.05±4.97 kg were used for the study. Animals were randomly divided into two equal groups and subcutaneously received either 0.25 mg/kg BW of letrozole or a control every week for 2 months. The semen collections were performed every 10 days, and blood samples and testicular biometric records were collected at 20 days intervals. Results: Letrozole causes increased testosterone and follicle-stimulating hormone levels, testosterone to estradiol ratio, semen index and reaction time during the period from 20th to 60th days (p<0.05). Furthermore, letrozole-treated bucks had higher semen volume, sperm concentration, and total sperm per ejaculate from 30th to 60th days (p<0.05). However, no differences occurred between the groups in scrotal circumference, relative testicular volume, semen pH, abnormality, acrosome integrity, and membrane integrity of sperm during the study (p>0.05). The serum luteinizing hormone levels, sperm viability, motility, and progressive motility increased, and estradiol levels decreased after 40th to 60th days of letrozole treatment (p<0.05). Conclusion: Letrozole application to aged Markhoz bucks provokes reproductive hormonal axis which, in turn, induces enhancement of semen production and quality.

Effects of Taurine on Sperm Characteristics during In vitro Storage of Boar Semen

  • Jang, H.Y.;Kong, H.S.;Park, C.K.;Oh, J.D.;Lee, S.G.;Cheong, H.T.;Kim, J.T.;Lee, S.J.;Yang, B.K.;Lee, H.K.
    • Asian-Australasian Journal of Animal Sciences
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    • 제19권11호
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    • pp.1561-1565
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    • 2006
  • The objective of this study was to investigate the anti-oxidative effects of taurine on sperm characteristics for in vitro storage of boar semen. Semen was randomly divided into 10 groups in conical tubes and treated with different concentrations of taurine (25-100 mM) with or without $250{\mu}M$ $H_2O_2$. The percentage of motile spermatozoa in taurine groups after 6 and 9 h were significantly higher at >94% and 87%, respectively, compared to the control group ($85.1{\pm}0.5$ and $72.4{\pm}0.3$, p<0.05). The sperm motility in taurine with $H_2O_2$ after 6 h incubation was slightly decreased compared to the taurine alone treatment, but after 9 and 12 h incubation % sperm motility dropped sharply in taurine with $H_2O_2$ ($75.3{\pm}0.3$ and $69.6{\pm}2.9$, p<0.05). For 3, 9 and 12 h incubation, sperm viability in the control was lower than in taurine groups, irrespective of taurine concentration. In eosin Y and nigrosin staining (ENS), the sperm survival rates (%) for 6 h incubation were significantly higher in 25 mM ($76.0{\pm}0.6$) and 50 mM taurine groups ($78.0{\pm}0.7$), respectively. Sperm survival rates for 9 and 12 h incubation were higher in taurine groups (${\geq}48%$ in 9 h and ${\geq}42%$ in 12 h) compared to controls ($43.0{\pm}2.1$ and $31.0{\pm}0.6$, respectively). In the hyoosmotic swelling test (HOST), sperm membrane integrity was similar to the results of sperm survival. These experiments indicate that supplementation of taurine to the semen extender can increase the sperm characteristics(motility, viability, survival and membrane integrity).