• Korean Chemical Engineering Research
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• v.49 no.5
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• pp.617-622
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• 2011

A simple method has been successfully applied to extract squalene and its byproducts alkoxyglycerol from deep-sea shark liver oil. GC-MS was used to determine the extraction amount of the squalene and alkoxyglycerol, and the content of them in rough product and refined product were compared. The physical property of squalene was identified by measuring the pH value, peroxide value and iodine value. Under optimum extraction conditions, the amount of squalene and alkoxyglycerol increased 35.0% and 21.9%, respectively, while the amount of fatty acid decreased from 61% to 4%, especially, the amount of palmitic acid and oleic acid remarkably decreased. Large amount of peroxide and acid were removed from shark liver oil after refining process. Because squalene contains lots of double bond, so the value of iodine is much higher than squalane.

• Journal of Information Processing Systems
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• v.11 no.2
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• pp.229-238
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• 2015

Web shells are programs that are written for a specific purpose in Web scripting languages, such as PHP, ASP, ASP.NET, JSP, PERL-CGI, etc. Web shells provide a means to communicate with the server's operating system via the interpreter of the web scripting languages. Hence, web shells can execute OS specific commands over HTTP. Usually, web attacks by malicious users are made by uploading one of these web shells to compromise the target web servers. Though there have been several approaches to detect such malicious web shells, no standard dataset has been built to compare various web shell detection techniques. In this paper, we present a collection of web shell files, WebSHArk 1.0, as a standard dataset for current and future studies in malicious web shell detection. To provide baseline results for future studies and for the improvement of current tools, we also present some benchmark results by scanning the WebSHArk dataset directory with three web shell scanning tools that are publicly available on the Internet. The WebSHArk 1.0 dataset is only available upon request via email to one of the authors, due to security and legal issues.

• Food Science and Preservation
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• v.16 no.3
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• pp.419-426
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• 2009

The antioxidant and antimicrobial effects of acid-soluble and pepsin-solubilizable shark (Isurus oxyrinchus) collagens (SC) (ASSC: acid-soluble shark skin collagen, ASMC: acid-soluble shark meat collagen, PSSC: pepsin-solubilizable shark skin collagen, PSMC: pepsin-solubilizable shark meat collagen) and standard marine collagen (STMC) as materials, and the ability of these materials to inhibit tyrosinase and elastase, were investigated. The electron-donating ability of SC ($1{\sim}5\;g/mL$) was $14.91{\sim}17.21%$, which was $3.0{\sim}3.6$-fold higher than that of STMC at the same concentration. Also, the SOD(superoxide dismutase)-like activity of SC (5.80 mg/mL) was $4.67{\sim}37.28%$, thus $3.0{\sim}3.6$-fold greater than that of STMC. The MIC values of SC against Staphylococcus aureus and Salmonella enteritidis were $5{\mu}g$/disc, which were remarkably lower than that of STMC ($200{\mu}g$/disc). There was no antimicrobial activity against Escherichia coli in STMC, but the MIC against E. coli was $200{\mu}g$/disc for acid-soluble SC and $100{\mu}g$/disc for pepsin-solubilizable SC. The inhibition of tyrosinase by SC (3-5 mg/mL) was $58.95{\sim}98.16%$, $3.34{\sim}3.74$-fold higher than that of STMC ($17.67{\sim}26.25%$). Also, elastase inhibition by SC (at 1 mg/mL) was $53.33{\sim}80.0%$, $1.1{\sim}4.0$-fold greater than that of STMC. These results indicated that shark collagens may be valuable new functional materials owing to their antioxidant and antimicrobial properties, and because the inhibitory activities against elastase and tyrosinase are better than those of standard marine collagen.

• Food Science and Preservation
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• v.17 no.4
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• pp.444-450
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• 2010

We investigated the quality of Dombaeki (shark meat) treated without salting (NS), with salting (S), air-packed (A), and vacuum-packed (V), during storage at $4^{\circ}C$ and $-18^{\circ}C$. We explored water holding capacity, elasticity, total bacterial counts, pH, titratable acidity level, volatile basic nitrogen (VBN) value, and drip loss. Water holding capacity and elasticity values were better when salting and vacuum-packaging were employed than when samples were not salted and were packaged in air. The total bacterial counts in SV meat were significantly lower than in other samples. The pH of all samples increased slowly during storage, and the pH values of NSA samples were significantly higher than the pH values of other samples. The VBN level and drip loss of SV meat were the lowest of all samples during storage. The results show that salted vacuum-packed meat was of better quality than that stored without salting, and air-packed, regardless of storage temperature.

• Journal of Life Science
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• v.6 no.4
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• pp.286-292
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• 1996

Angiogenesis is a fundamental process by which new blood vessels are formed. It is essential in embryo development, and wound healing. Furthermore, malignant tumor growth and metastasis are also angiogenesis-dependent. In the catilage tissue, normal angiogenesis process is suppressed. In fact, it was reported that angiogenesis-inhibitory substances were isolated from the extracts of cow and shark catilage tissue. In order to isolate genes involved in the regulation of angiogenesis from a catilage fish, we constructed a shark cDNA library from Scylliohinus torazame. We then screened the library using hyman tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) gene as a probe. Among the 4 X 10$^{4}$ plaques screened, we isolated 2 positive clones (T-1, T-2). Restriction enzyme analysis revealed that the T-1 clone contains 0.8 kb cDNA insert, and the T-2 clone contains 1.2 kb and 2.2 kb inserts, respectively. Further DNA sequence analysis shows that the DNA sequence of the T-1 clone is 53% homologous to that of the human TIMP-1 gene.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.6
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• pp.696-701
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• 2019

Five specimens (839 - 1280 mm TL, Total length) of the dusky shark Carcharhinus obscurus, belonging to the family Carcharhinidae, were collected from the waters off Jejudo Island, Sinan, Namhae, Busan and Gangneung, Korea, during 2010-2019. Carcharhinus obscurus was similar to Carcharhinus brachyurus but was distinguished by the interdorsal ridge (present in C. obscurus vs. absent in C. brachyurus) and the shape of upper jaw teeth (broad in C. obscurus vs. narrow in C. brachyurus). In addition, 479 base-pair sequences in the mitochondrial DNA cytochrome c oxidase subunit I (COI) of our two specimens corresponded to those of C. obscurus (genetic distance, 0.000-0.003), but clearly distinguished from those of the Korean C. brachyurus (genetic distance, 0.03). We adopted the Korean name "Heuk-sang-eo" for Carcharhinus obscurus, after Kim and Ryu (2017).

• Food Science and Biotechnology
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• v.14 no.5
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• pp.651-655
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• 2005

Enzymatic hydrolysis of shark (Squatina oculata) cartilage (SC) was optimized by response surface methodology (RSM) for chondroitin sulfate (CS) preparation. Among 11 commercial proteases, Maxazyme NNP showed highest productivity (CS yield per enzyme cost) of CS. Optimal hydrolysis conditions determined by RSM were 1.63% and 2.87 hr for enzyme concentration and hydrolysis time ($r^2\;=\;0.9527$, p<0.0l), respectively and highest yield of hydrolysate under the conditions was 42.3%. The yield ($43.1{\pm}2.1%$) and CS content ($24.8{\pm}0.1%$) of hydrolysate at optimal condition verified statistical optimization of SC enzymatic hydrolysis was valid.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.3
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• pp.254-261
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• 2010

The feeding habits of six shark species, Scyliorhinus torazame, Mustelus manazo, Squalus megalops, Isurus oxyrinchus, Alopias pelagicus, and Carcharhinus plumbeus were studied using the stomach contents of 463 specimens collected between January and February 2007 in the southern sea of Korea. They consumed different prey items. S. torazame preyed mainly crustaceans, and M. manazo on crustaceans and fishes. S. megalops, I. oxyrinchus, A. pelagicus, and C. plumbeus consumed predominately fishes. Non-metric multi-dimensional scaling (NMDS) ordination plots emphasized that dietary similarities separated thesix shark species into three trophic groups based on similarities in percentage Index of Relative Importance (%IRI): Group I (crustacean feeders), Group II (fish and crustacean feeders), and Group III (fish feeders).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.2
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• pp.147-153
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• 1983

To check the differences of the digestive enzymes by the bait habits and the proteolytic activities of the fissile extracts from the fish, omnivorous filefish (Navodon modestus), carnivorous cat shark (Scilliorhinus tarazame) and bloodsucking hag fish (Eptatretus burgeri) were sampled for this experiment. The activity of crude alkaline protease extracted from the muscle and the internal organs of the samples was determined with casein as substrate. The activity of the proteolytic enzymes showed remarkable differences by the organs of the fish. The optimum condition of the pretenses from the muscle revealed in range of pH 7.8-8.3, at $60-65^{\circ}C$, while those of the enzymes from the internal organs were at about pH 8.2, $45-55^{\circ}C$, but those of hag fish were at about pH 6.7, $45-55^{\circ}C$. The proteolytic activity of the enzyme of alimentary canal in filefish and in hag fish was 57 and 11 times stronger than that of muscle, respectively. The crude enzyme from the alimentary canal of file fish showed the strongest proteolytic activity in samples submitted and that of cat shark was the lowest. The activity of pancreatic alkaline protease in cat shark was 50 fold higher than that of muscle alkaline protease in the fish.

• Tribology and Lubricants
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• v.35 no.2
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• pp.94-98
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• 2019

The riblet structure like shark skin has been widely studied owing to its drag reduction and anti-fouling properties. In this study we simulated the wettability of an oil droplet on a riblet surface. We developed a numerical analysis method using the Wenzel equation and Cassie-Baxter equation that can estimate the contact angle with a penetrated depth of the droplet on rough surfaces. Riblet surfaces with nine scales composed of five hemi-elliptical ribs are generated numerically. The variation of contact angles with fractional depth of penetration for the generated riblet surfaces with and without coatings is demonstrated in the condition of solid-air-oil and solid-water-oil interfaces. The contact angle for the uncoated surface decreases with increasing fractional depth of penetration more drastically than that for the coated surface. For the effect of surface roughness on the contact angle of the droplet, the oleophilic surface gives lower contact angle when the surface is rougher, whereas the oleoophobic surface gives higher contact angle with higher roughness To verify the analysis results, the wetting angle was measured in the solid-air-oil interface and solid-water-oil interface for the shark-skin template and shark-skin replica. The effects of teflon coating were also evaluated. It is shown that the simulation results cover the experimental ones.