• Korean Journal of Acupuncture
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• 제23권4호
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• pp.135-145
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• 2006

Objectives and Methods : Using the 2-channel DROS SQUID (Korea Research Institute of Standards of Science, 1999), the present study was carried out to record changes elicited in the auditory cortex by acupuncture stimulus on right TE5 (Waiguan) and GB43 (Xiaxi). Needle-retention stimulation of TE5 and GB43 were done for acquiring the brain activities changed by acupuncture. Acupoint TE5 and GB43 is known to be effective for the treatment of ear-related disease, such as deafness and tinnitus, and to be suspected to be related to the auditory cortex. Auditory evoked magnetic fields were recorded hem the left hemisphere of five subjects, in response to contralateral ear stimulation by irregularly spaced 170 msec long 1kHz tone busts (Korea Research Institute of Standards of Science) Results and Conclusions : The result as follows. The latency and amplitude of SQUID MEG responses at the human auditory cortex changed by needle-retention condition on TE5 were 4msec and 9.2 fT, respectively, which were slower and smaller than those of no-acupuncture condition. The latency and amplitude of SQUID MEG responses at the human auditory cortex changed by needle-retention condition on GB43 were 7.2 msec and 1.6 fT, respectively, which were slower and larger than those of no-acupuncture condition. The latency of SQUID MEG responses at the human auditory cortex changed by needle-retention condition on GB43 condition was slower than that of TE5 acupuncture condition.

• Progress in Superconductivity
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• 제13권3호
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• pp.139-145
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• 2012

Electric activity of cardiac muscles generates magnetic fields. Magnetocardiography (or MCG) technology, measuring these magnetic signals, can provide useful information for the diagnosis of heart diseases. It is already about 40 years ago that the first measurement of MCG signals was done by D. Cohen using SQUID (superconducting quantum interference device) sensor inside a magnetically shielded room. In the early period of MCG history, bulky point-contact RF-SQUID was used as the magnetic sensor. Thanks to the development of Nb-based Josephson junction technology in mid 1980s and new design of tightly-coupled DC-SQUID, low-noise SQUID sensors could be developed in late 1980s. In around 1990, several groups developed multi-channel MCG systems and started clinical study. However, it is quite recent years that the true usefulness of MCG was verified in clinical practice, for example, in the diagnosis of coronary artery disease. For the practical MCG system, technical elements of MCG system should be optimized in terms of performance, fabrication cost and operation cost. In this review, development history, technical issue, and future development direction of MCG technology are described.

• 대한의용생체공학회:의공학회지
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• 제24권3호
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• pp.159-165
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• 2003

뇌자도 측정을 위해 고감도 superconducting quantum interference device (SQUID) 자력계 및 37채널 뇌자도 측정장치를 제작하고 동작특성을 조사하였다. 자속-전압 변환계수 및 변조전압 진폭이 큰 double relaxation oscillation SQUID (DROS)를 사용함으로서 구동회로를 간단히 하였고 안정한 SQUID 동작을 실현할 수 있었다. DROS 자력계를 설계 및 제작한 결과 자력계의 평균 백색잡음은 약 3 fT/√Hz으로서 우수한 자장감도를 가짐을 확인하였다 머리의 평균곡률을 기반으로 37개의 자력계를 반구형으로 배치시켰으며, 외부잡음을 줄이기 위해 신호채널 외에 11개의 기준채널을 설치하여 소프트웨어 방법으로 합성미분계 및 적응필터링을 형성할 수 있도록 하였다 저잡음 듀아를 제작하여 동작특성을 측정한 결과 듀아 열자기 잡음이 자력계 잡음에 비해 무시할 수 있는 수준이었으며, 듀아의 용량은 30 L, 액체헬륨 증발율은 4 L/d이다. 제작된 시스템을 이용하여 청각유발 신호를 측정하고, 디지털 신호처리 및 전류원 국지화 프로그램을 구성하여 전류원의 위치를 추정함으로서 개발된 시스템을 뇌자도 측정에 활용하였다.

• Food Science and Biotechnology
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• 제18권3호
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• pp.761-765
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• 2009

The effects of probiotic bacteria on the functional properties of squid by-products were investigated during fermentation. Bifidobacterium longum, Lactobacillus acidophilus, Lactobacillus brevis, Lactobacillus casei, Lactobacillus paracasei, Lactobacillus rhamnosus, and Pediococcus acidilactici were used to ferment the squid by-products for 96 hr at $37^{\circ}C$. The numbers of all probiotics increased to $10^7-10^8$ CFU/g after 96 hr fermentation. No substantial pH changes were observed. L. rhamnosus and P. acidilactici showed the highest 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activities. Interleukin-6 (IL-6) and tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$) secreted from B cells increased after adding the extracts of probiotic-fermented squid by-products. The human NK cells were grown well in the B cell-growing broth cultured with the extracts of squid by-products fermented by L. rhamnosus and P. acidilactici. Trimethylamine (TMA) and dimethylamine (DMA) contents were significantly decreased after probiotic-fermentation. Therefore, L. rhamnosus GG and P. acidilactici can be used for the fermentation of squid by-products and their use would provide benefits in functional food products.

• 한국수산과학회지
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• 제30권5호
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• pp.859-867
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• 1997

오징어 가공중 부산물로 배출되는 오징어 연골의 효율적 이용을 위한 기초 단계로서 우리나라 연안산과 남미 포클랜드산 오징어 연골로부터 chitosan을 제조하여 그레올로지 특성을 조사한 결과를 요약하면 아래와 같다. 연안산 오징어 연골의 질소와 회분 함량은 각각 $11.4\%$와 $0.7\%$ 이었으며, 남미산 오징어 연골의 질소와 회분 함량은 각각 $12.1\%$와 $0.8\%$ 이었다. 그리고 chitosan에서 질소함량은 연안산이 $7.5\%$ 이었고, 남미산은 $7.8\%$ 이었다. 각 chitosan의 탈아세틸화도와 분자량은 각각 $90\%$, $1.08\times10^6$과 $90\%,\;1.20\times10^6$ 이었고, 수율은 각각 $26.4\%,\;25.7\%$ 이었다. pH 변화$(pH\;3.4\~5.4)$에 따른 연안산과 남미산 오징어 연골 chitosan의 고유점도의 변화는 pH가 증가할수록 두 chitosan의 고유점도는 감소하는 경향을 나타내었고, 연안산과 남미산을 비교해 보면 전체 pH 영역에서 남미산이 조금 높은 고유점도를 나타내었으나 pH 증가에 따른 고유점도의 강소 경향에는 차이는 없었다. NaCl의 농도가 증가할수록 두 시료 chitosan의 고유 점도는 감소하는 것으로 나타났다. 오징어 연골 chitosan의 $[\eta]\infty$는 연안산과 남미산 각각 $3.5970d\ell/g$ 및 $3.248d\ell/g$이었고, 사슬의 유연성 (B)은 두 시료 공히 0.11 이었다. 연안산 오징어 연골 chitosan $0.5\%$ 용액의 경우 유동 곡선은 항복응력이 없는 의가소성 유체로 분류할 수 있었다. 남미산 오징어 연골 chitosan 용액의 경우는 거의 직선에 가까운 유동곡선을 나타내어 뉴우튼 유체에 가까웠다. 연안산과 남미산 오징어 연골 chitosan의 각 온도별 유동지수는 농도가 낮아질수록 온도가 높아질수록 뉴우튼 유체의 거동에 가까워지고 있음을 나타내었다 농도에 따른 점조도지수 (K)의 변화에서 각 온도별 오징어 chitosan용액의 유동특성이 달라지는 임계농도는 연안산이 $0.15\~0.24\%$ 범위이었고, 남미산은 $0.21\~0.24\%$ 범위이었다. 각 농도에서 구한 활성화에너지는 $0.1\%$에서 $0.5\%$까지 순서대로 연안산 오징어 연골 chitosan은 각각 3.7, 6.3, 3.6, 4.0 및 4.1 kcal/g mol 이었고, 남미산 오징어 연골 chitosan은 각각 3.2, 3.1, 3.4, 3.8 및 3.6 Kcal/g mol 이었다.

• 한국식품영양과학회지
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• 제24권4호
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• pp.636-641
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• 1995

Proteolytic activities were compared using three species involving in squid jeotkal fermentation and showing positive reaction upon casein test : Pseudomonas D2, Flavovacterium odoratum and Acinetobacter calcoaceticus. Pseudomonas D2 produced highest activity of protease at 72h when incubated in our own modified medium(polypeptone, 0.5% ; tryptone, 0.5% ; NaCl, 3% ; pH, 7.5). Thus, this specie was selected for the further study. The growth pattern was coincided with the production of protease. Thus purification of protease was proceeded by ethanol precipitation, sephadex G-100 gel filtration, and DEAE sepharose ion exchange chromatography. The purified protease showed highest activity at pH 7.0 and 5$0^{\circ}C$. The enzyme was very stable over the wide ragnes of the temperature ; even with one hour heat treatment at 7$0^{\circ}C$, the enzyme showed substantial amount of the activity toward casein. In addition, the enzyme was stable over the wide range of pH. Molecular weight of the protease was determined to be 17.4 kD by SDS-PAGE.

• 한국식품영양과학회지
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• 제30권2호
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• pp.292-298
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• 2001

This study was conducted to investigate physicochemical properties of extrudates combining 4 levels of squid (0, 3, 5 and 7%) with 3 levels of defatted soy flour (0, 5, and 10%). Blends were adjusted to moisture content of 27% and then extruded in a single-screw laboratory extruder at 170rpm screw speed and 16$0^{\circ}C$ barrel temperature. The extruded materials were dried at 6$0^{\circ}C$ for 8hr to a moisture content of 3~4% and refrigerated at 4$^{\circ}C$ for 12 hour before examination for textural properties, expansion ratio, bulk density, shear force and Hunter color. Expansion ratio of extrudates decreased as squid content increased whereas bulk density and shear force increased. Expansion ratio of extrudates was not significantly different by defatted soyflour level. Bulk density of products decreased as defatted soyflour content increased but shear force of products increased as defatted soyflour content increased. In scores of sensory hedonic evaluation of snacks, appearance, flavor, texture and overall acceptability values had lowered as squid level increased. Therefore, according to materials contents on extrudates increased, nutritional contents of this products increased and also shear force and bulk density in physical properties increased whereas expansion ratio decreased.

• 한국수산과학회지
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• 제29권6호
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• pp.754-760
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• 1996

Effects of washing and additives on the texture of squid surimi gel which has been known to hard to gelation due to high protease activities and many water solubles were studied by SDS-PAGE, compression test, jelly strength and transmission electron microscopy analysis (TEM). Myosin (205 kDa) heavy chain was the major protein in water soluble fractions. It was impossible to make a gel after washing of the minced squid meat. These results suggested that squid (Todarodes pacificus) minced meat does not need a washing for good jelly products. $3.0\%$ of bovine plasma protein (BPP) produced the hardest gel ($16\%$ harder than the control) among the additives including egg white (EW), potato extracts (PE) and transglutaminase-K (TG-K) by compression test (P>0.05). Microstructure of control, $2\%$ EW and $4\%$ TG-K treated gels showed a sponge-like structure with more vacant space. Gels containing $3\%$ BPP formed the most rigid and arranged networks. Those results indicates that poor gel-network formation Was due to the degradation of myofibrillar proteins by proteases contained in the minced meat, which result in non-interlinkage.

• 수산해양기술연구
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• 제34권2호
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• pp.105-116
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• 1998

This paper, examines the relationship between water temperatures and fishing conditions of common squid by the squid angling fishery from June to September in 1993-1995. The condition of the common squid fishing largely depended on the fluctuation of water temperature in the coastal area of Gampo. Monthly mean water temperatures during June m September in 1993 and 1994 were relatively higher than those in 1995 in Gampo area. But the values between July and August in 1995 were about 5$^{\circ}C$ lower than those in 1993 and 1995. Coefficients of variation (CV) of water temperature showed the lowest value during July ~ September in 1993, however, the highest value was observed in July and August in 1994. Catch per unit effort (CPUE ; kg/angling) showed a peak with 73.7kg in 1993 when the CV was low. On the other hand, the lowest CPUE of 39.6kg was observed in 1994 when the CV was high. It was concluded that the high stability of water temperatures and the weak strength of cold water have caused the good fishing conditions of common squid.

• 한국수산과학회지
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• 제44권2호
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• pp.118-125
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• 2011

In this study, an angiotensin I-converting enzyme (ACE) inhibitor from squid skin was purified and characterized. Squid (Todarodes pacificus) skin protein isolates were hydrolyzed using six commercial proteases: alcalase, ${\alpha}$-chymotrypsin, neutrase, papain, pepsin, and trypsin. The peptic hydrolysate had the highest ACE inhibitory activity. The ACE inhibitory peptide was purified using Sephadex G-25 column chromatography and reverse phase high-performance liquid chromatography (HPLC) with a $C_{18}$ column. The purified ACE inhibitory peptide was identified and sequenced, and found to consist of seven amino acid residues: Ser-Ala-Gly-Ser-Leu-Val-Pro (657Da). The $IC_{50}$ value of the purified ACE inhibitory peptide was 766.2 ${\mu}M$, and Lineweaver-Burk plots suggested that the purified peptide acts as a noncompetitive ACE inhibitor. These results suggest that the ACE inhibitory peptide purified from the peptic hydrolysate of squid skin may be of benefit in developing antihypertensive drugs and functional foods.