• Asian-Australasian Journal of Animal Sciences
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• v.33 no.2
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• pp.212-218
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• 2020

Objective: Agu pigs are indigenous to the Okinawa prefecture, which is the southernmost region of Japan. Agu pigs were exposed to a genetic bottleneck during the 20th century, due to the introduction of European pig breeds. The objective of this study was to elucidate the genetic structure of Agu pigs and to determine their relationships with those of five European breeds, two Chinese breeds and Ryukyu wild boar using microsatellite markers. Methods: A total of 203 DNA samples from 8 pig breeds were used in this study. Genotyping was performed using 21 microsatellite markers distributed across 17 chromosomes. Results: Numbers of effective alleles in Agu pigs were fewer than in European breeds and Ryukyu wild boar. Among domestic pigs, Agu pigs had the lowest heterozygosity (0.423) and highest inbreeding coefficient (F_IS = 0.202), indicating a severe loss of heterozygosity in Agu pigs possibly due to inbreeding. Neighbor-joining tree analysis was performed based on Reynolds' genetic distances, which clustered Agu pigs with Duroc pigs. However, principal component analysis revealed a unique genetic position of the Agu pig, and the second principal component separated Agu pigs from all other breeds. Structure analysis with the optimal assumption of seven groups (K = 7) indicated that Agu pigs form an independent cluster from the other breeds. In addition, high and significant F_ST values (0.235 to 0.413) were identified between Agu pigs and the other breeds. Conclusion: This study revealed a substantial loss of genetic diversity among Agu pigs due to inbreeding. Our data also suggest that Agu pigs have a distinctive genetic structure, although gene flows from European breeds were observed.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.4
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• pp.501-507
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• 2019

Objective: The Agu is the only native pig breed in Japan, which is reared in Okinawa prefecture, the southernmost region in Japan. Its origins are considered to be of Asian lineage; however, the genetic background of the Agu is still unclear. The objective of this study was to elucidate the maternal lineage of the Okinawa indigenous Agu pig with the use of the mitochondrial DNA (mtDNA) control region. Methods: The mtDNA control regions of Agu pigs were sequenced and the phylogenetic relationship among Agu, East Asian and European pigs was investigated with the use of 78 Agu individuals. Results: Twenty-seven polymorphic sites and five different haplotypes (type 1 to type 5) were identified within the Agu population. Phylogenetic analysis indicated that types 1 and 2 were included in East Asian lineages; however, the remaining types 3, 4, and 5 were of European lineages, which showed a gene flow from European pigs in the 20th century. Sixty-seven out of 78 Agu individuals (85.9%) possessed mtDNA haplotypes 1 and 2 of the East Asian lineage, which were identical to two haplotypes of ancient mtDNA (7,200 to 1,700 years before the present) excavated at archaeological sites in Okinawa. Conclusion: This study confirmed that the East Asian lineage is dominant in the maternal genetic background of the Agu population, supporting the hypothesis that the ancestors of the Agu pig were introduced from the Asian continent.

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.40-44
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• 2001

The effects of TEMPO and NaBr concentration, and temperature on the selective oxidation of primary alcohol groups in corn starch were examined. Reaction time decreased with the increased levels of TEMPO, NaBr and temperature up to 1.7 mM and 100 mM per 100 mM anhydroglucose unit(AGU) and $14^{\circ}C$, respectively, and did not change appreciably at the higher levels. Yield decreased with the increased NaBr levels and was not affected TEMPO level and the temperature. NaBr level and temperature showed negative effects on the selectivity. But the selectivity was not affected by NaBr level and temperature until 100 mM/100 mM AGU and $6^{\circ}C$. TEMPO had no effect on the selectivity significantly.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.580-586
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• 1996

Gelatinization behavior and morphology of epichlorohydrin-crosslinked potato starches (XPs) were investigated. Native potato starch showed a very steep single stage swlling pattern, but crosslinked starches showed various patterns with the degree of crosslinking. Swelling power, solubility and light transmittance were reduced drastically as the degree of crosslinking increased. Brabender initial pasting temperature and peak temperature of crosslinked starches increased because the crosslinking reinforces the intermolecular net work of the starches. Although the swelling of the potato starch granule was inhibited by crosslinking as compared to that of the native one, Brabender peak viscosities (6.5% w/v, db) were on the order of 2,500 units for the native potato starch, 3,700 for the XP with 2.300 anhydroglucose units per crosslinking (AGU/CL) and 3,400 for the XP with 2,100 AGU/CL, due to the decreased breakdown of the swollen granule resulting from the resistance to heat and shear. The XP with 1,900 AGU/CL, however, did not show the peak viscosity and the viscosity was on the order of 500 units because of the excessive unhibition of the swelling. Unlike the native potato starch, 6.5%(m/v, db) pastes of the crosslinked potato starches could form gels, which could be predicted from the Brabender setback and consistency index. When the degree of crosslinking is low, random contraction and radial swelling of the granule was possible. As the degree of crosslinking increased, morphological change became similar to the single dimensional tangential swelling observed from the lenticular wheat starch. These morphological change during heating in excess water explained the gelatinization behaviors of crosslinked starches tested.

• Water for future
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• v.55 no.2
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• pp.74-84
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• 2022

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.573-579
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• 1996

Crosslinked potato starches (XP), from 2,400 to 1,900 anhydroglucose units per crosslinked (AGU/CL), were prepared by reacting with epichlorohydrin. Some of the physicochemical properties of the XPs were then compared with those of native potato and cowpea starches. Crosslinking decreased moisture, protein and ash contents but had no effect on phosphorus content. Water binding capacities of the XPs increased as the degree of crosslinking increased, and that of the XP with 2,100 AGU/CL approached the value of cowpea starch. The absorption maxima of the starch-iodine complex shifted from 594 to 580 nm. Granule size increased slightly and surface appearance of the granule became rough when crosslinked. Both native and crosslinked potato starches showed B type X-ray diffraction pattern, and the relative crystallinity was not affected by crosslinking. Gelatinization temperature and the heat of gelatinization, measured by differential scanning calorimeter (DSC), did not change within the range of crosslinking tested. From X-ray and DSC data, it was concluded that the crosslinking ocurred in the amorphous region of the starch granule.

• International Journal of Oral Biology
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• v.44 no.2
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• pp.31-36
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• 2019

Streptococcus mutans is one of the important bacteria that forms dental biofilm and cause dental caries. Virulence genes in S. mutans can be classified into the genes involved in bacterial adhesion, extracellular polysaccharide formation, biofilm formation, sugar uptake and metabolism, acid tolerance, and regulation. The genes involved in bacterial adhesion are gbps (gbpA, gbpB, and gbpC) and spaP. The gbp genes encode glucan-binding protein (GBP) A, GBP B, and GBP C. The spaP gene encodes cell surface antigen, SpaP. The genes involved in extracellular polysaccharide formation are gtfs (gtfB, gtfC, and gtfD) and ftf, which encode glycosyltransferase (GTF) B, GTF C, and GTF D and fructosyltransferase, respectively. The genes involved in biofilm formation are smu630, relA, and comDE. The smu630 gene is important for biofilm formation. The relA and comDE genes contribute to quorumsensing and biofilm formation. The genes involved in sugar uptake and metabolism are eno, ldh, and relA. The eno gene encodes bacterial enolase, which catalyzes the formation of phosphoenolpyruvate. The ldh gene encodes lactic acid dehydrogenase. The relA gene contributes to the regulation of the glucose phosphotransferase system. The genes related to acid tolerance are atpD, aguD, brpA, and relA. The atpD gene encodes $F_1F_0$-ATPase, a proton pump that discharges $H^+$ from within the bacterium to the outside. The aguD gene encodes agmatine deiminase system and produces alkali to overcome acid stress. The genes involved in regulation are vicR, brpA, and relA.

• Journal of Aerospace System Engineering
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• v.16 no.4
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• pp.77-87
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• 2022

The Precision Aerial Delivery System is an instrument designed to improve the poor landing accuracy of aerial delivery system with conventional circular parachutes, and is equipped with an Airborne Guidance Unit to safely transport supplies to the desired destination. Currently, the landing accuracy of the PADS product is reported as CEP₅₀ 100m and also differs significantly, depending on the actual topography and weather environment. In this study, HILS was constructed based on the 6DOF nonlinear modeling of PADS to analyze the maneuver characteristics of Ram Air Parachute under wind environments. By using the new algorithm a precision soft landing algorithm including Energy Management and Final Approach is designed. HILS results show that it is possible to achieve a precise soft landing within CEP₅₀ 40m, and it can be exploited to develop an actual PADS drop test.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.1-4
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• 2011

Detonation is useful phenomena to get an effective thrust for aerospace vehicle. Fast pressure rise of detonation provides a cycle close to the constant volume system to use energy efficiently. From this point detonation can be used as an aerospace engine system. There are several types of detonation engine; pulse detonation engine (PDE) which provides a thrust by detonation intermittently, and oblique detonation engine (ODE), spin detonation engine (SDE), and rotating detonation engine (RDE) which, on the other hand, provide a continuous thrust.

• Publications of The Korean Astronomical Society
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• v.20 no.1 s.24
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• pp.117-124
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• 2005

We plan to install the polarimetric optics in the AGU(acqusition and guiding unit) of the 1.8 m telescope at the BOAO(Bohyunsan Optical Astronomy Observatory). With this, the spectropolarimetric observations with the resolution of 45,000 and 60,000 in 4,000 to $8,000{\AA}$ ange could be done by the BOES(BOao Echelle Spectrograph). If we use the precision radial velocity measurement capability of the BOES, the accuracy of the magnetic field intensity measurements with this new BOES stokesmeter will be much increased. We present here the design concept of the BOES stokesmeter. Some details on the optics, mechanical parts, fiber parts and the lab test procedures of this stokesmeter are explained.