Potency of cashew nut shell liquid in rumen modulation under different dietary conditions and indication of its surfactant action against rumen bacteria

( Seongjin Oh ),( Yasuyuki Suzuki ),( Shusuke Hayashi ),( Yutaka Suzuki ),( Satoshi Koike ),( Yasuo Kobayashi ) 한국축산학회(구 한국동물자원과학회) 2017 한국축산학회지 Vol.59 No.11

Background: Cashew nut shell liquid (CNSL) is an agricultural byproduct containing alkylphenols that has been shown to favorably change the rumen fermentation pattern only under experimentally fixed feeding conditions. Investigation of CNSL potency in rumen modulation under a variety of feeding regimens, and evidence leading to the understanding of CNSL action are obviously necessary for further CNSL applications. The objective of this study was to evaluate the potency of CNSL for rumen modulation under different dietary conditions, and to visually demonstrate its surfactant action against selected rumen bacteria. Methods: Batch culture studies were carried out using various diets with 5 different forage to concentrate (F:C) ratios (9:1, 7:3, 5:5. 3:7 and 1:9). Strained rumen fluid was diluted with a buffer and incubated with each diet. Gas and short chain fatty acid (SCFA) profiles were characterized after 18 h incubation at 39 °C. Monensin was also evaluated as a reference additive under the same conditions. Four species of rumen bacteria were grown in pure culture and exposed to CNSL to determine their morphological sensitivity to the surfactant action of CNSL. Results: CNSL supplementation decreased total gas production in diets with 5:5 and 3:7 F:C ratios, whereas the F:C ratio alone did not affect any gas production. Methane decrease by CNSL addition was more apparent in diets with 5:5, 3:7, and 1:9 F:C ratios. An interactive effect of CNSL and the F:C ratio was also observed for methane production. CNSL supplementation enhanced propionate production, while total SCFA production was not affected. Monensin decreased methane production but only in a diet with a 1:9 F:C ratio with increased propionate. Studies of pure cultures indicated that CNSL damaged the cell surface of hydrogen- and formate-producing bacteria, but did not change that of propionate-producing bacteria. Conclusion: CNSL can selectively inhibit rumen bacteria through its surfactant action to lead fermentation toward less methane and more propionate production. As CNSL is effective over a wider range of dietary conditions for such modulation of rumen fermentation in comparison with monensin, this new additive candidate might be applied to ruminant animals for various production purposes and at various stages.

In vitro and in vivo evaluation of kenaf (Hibiscus cannabinus L.) as a roughage source for beef cattle

Oh, Seongjin,Mbiriri, David Tinotenda,Ryu, Chaehwa,Lee, Kangheon,Cho, Sangbuem,Choi, Nag-Jin Asian Australasian Association of Animal Productio 2018 Animal Bioscience Vol.31 No.10

Objective: The goal of this study was to evaluate kenaf as a roughage source in vitro and its effects on meat quality of Hanwoo (Korean native) cattle. Methods: Three roughage materials, rice straw silage, ryegrass silage, and kenaf silage, were tested in a batch culture and feeding trial. Rumen fermentation parameters, including gas, pH, volatile fatty acid (VFA), and ammonia were analyzed. In the feeding trial, Hanwoo steers ($373.5{\pm}5.1kg$, n = 36, 11 month of age) were divided into three feeding groups (n = 12 each). Animals were fed with each silage and concentrate until the fattening stage. Results: Crude protein, ether extract, and non-structural carbohydrates were greater in kenaf silage. Total gas production was higher in ryegrass silage, followed by kenaf silage and rice straw silage (p<0.05). Total VFA and individual VFA (acetate, propionate, and n-butyrate) were greater in kenaf silage than rice straw silage (p<0.05). In vitro dry matter digestibility showed a similar trend to that of total gas and VFA production; it was higher in ryegrass silage and lower in rice straw (p<0.05). Throughout the feeding trial, the rice straw silage group showed significantly greater average daily gain than did the others (p<0.05). The feed conversion ratio in the group fed kenaf silage was significantly greater than that of others (p<0.05). No significant differences were observed in yield or quality traits, including carcass weight, ribeye area, backfat thickness, and scores for marbling, meat color, and fat color (p>0.05). Conclusion: The results indicated that no negative effects on growth performance and carcass characteristics occurred across treatments. Therefore, kenaf could be substituted for rice straw, which is most widely used as a roughage source in Korea.

ESS용 PCS 기술 및 신재생에너지 지원 ESS의 고찰

오성진(Seongjin Oh) 한국신재생에너지학회 2018 한국신재생에너지학회 학술대회논문집 Vol.2018 No.4

실시간 운영체제 DSP/BIOS를 이용한 3상 무정전전원공급장치(UPS) 소프트웨어 설계

오성진(Seongjin Oh),김경환(Kyunghwan Kim),이동근(Dongkeun Lee) 전력전자학회 2006 전력전자학술대회 논문집 Vol.- No.-

대부분의 전력전자 시스템과 마찬가지로 3상 UPS 시스템 역시 전력전자 알고리즘 개발자가 응용프로그램을 작성할 때 하드웨어를 조작하고 초기화하는 하위 수준 코드를 작성해 왔다. 이와 같은 응용 소프트웨어와 하드웨어의 밀접한 통합은 시스템 성능차원에서는 부족함이 없으나 이식성과 유지보수 측면에서 많은 문제점을 보여 왔다. 또한, 다양화 된 고객요구에 의하여 시스템이 점점 더 복잡해짐에 따라서 기존 소프트웨어 구성은 한계를 이르렀다. 본 논문에서는 TI사의 실시간 운영체제인 DSP/BIOS를 이용하여 3상 UPS 시스템 하드웨어와 용용프로그램을 분리하는 추상화 작업을 통해서 이루어진 성과에 관하여 제시한다. 분업화되고 상호 연동하는 방식의 개발 패러다임의 변화는 전력전자 알고리즘 개발자가 더 많은 시간을 알고리즘 개발에 투입 할 수 있게 하였고 다른 분야 개발자가 병렬로 소프트웨어 개발을 진행함에 따라서 전체적으로 개발기간의 단축을 가져왔다.

새로운 독일의 계통규정(New German Grid Code)에 관한 고찰

오성진(Seongjin Oh) 전력전자학회 2010 전력전자학술대회 논문집 Vol.2010 No.7

본 논문에서는 신재생에너지 발전 설비 증가에 따른 계통의 불안정성을 극복하기 위하여, 독일 BDEW(German Association of Energy and Water Industries)가 제정한 특고압(Medium Voltage) 계통 연계 신재생 에너지 발전 시스템에 대한 계통 연계 규정에 대해서 기술한다. 득히, 태양광 인버터 관점에서 독일의 새로운 계통연계 규정이 요구하고 있는 내용에 대해서 설명한다.

Two-mode Fiber with a Reduced Mode Overlap for Uncoupled Mode-division Multiplexing in C+L Band

Seongjin Hong,Kyoungyeon Choi,Yong Soo Lee,Kyunghwan Oh 한국광학회 2018 Current Optics and Photonics Vol.2 No.3

We proposed a two-mode fiber (TMF) design that can effectively reduce the mode overlap between LP<SUB>01</SUB> and LP<SUB>11</SUB> modes by using a W-shaped index profile core structure, which is a primary concern in uncoupled mode division multiplexing (MDM). TMF has a three-layered core structure; central circular core, inner cladding, and outer ring core. We confirmed that in an optimal structure the LP<SUB>01</SUB> mode was highly confined to the central core while the LP<SUB>11</SUB> mode was guided along the outer ring core to result in a minimum overlap integral. We used a full-vectorial finite element method to estimate effective index, differential group delay (DGD), confinement loss, chromatic dispersion, and mode overlap controlling the parameters of the W-shaped structure. The optimized W-profile fiber provided optical characteristics within the ITU-T recommended standards over the entire C+L band.

Optimization of Diode-pumped Cesium Vapor Laser Using Frequency Locked Pump Laser

Seongjin Hong,Byungjoo Kong,Yong Soo Lee,Kyunghwan Oh 한국광학회 2018 Current Optics and Photonics Vol.2 No.5

We propose a diode-pumped cesium laser using frequency locking of a pump laser that can effectively increase the maximum output power of the cesium laser. We simultaneously monitored the absorption spectrum of cesium and the laser output power, and the frequency of pump laser was locked at the center of the D2 absorption line of the cesium atom to obtain an effective gain enhancement. Using this scheme, we have achieved output power increase of ~0.1 W compared to when frequency locking was not applied. Furthermore, by optimizing the temperature of the cesium cell and the reflectivity of the output coupler, we successfully achieved an output power of 1.4 W using the pump power of 2.9 W, providing a slope efficiency of 61.5% and optical-to-optical efficiency of 49%.

Numerical Analysis on Separation Dynamics of Strap-On Boosters in the Dense Atmosphere

Seongjin Choi,Soon-Heum Ko,Chongam Kim,Oh-Hyun Rho,Jeong-joo Park 한국항공우주학회 2001 International Journal of Aeronautical and Space Sc Vol.2 No.2

Localized Eigenmodes in a Triangular Multicore Hollow Optical Fiber for Space-division Multiplexing in C+L Band

Seongjin Hong,Kyunghwan Oh 한국광학회 2018 Current Optics and Photonics Vol.2 No.3

We propose a triangular-multicore hollow optical fiber (TMC-HOF) design for uncoupled mode-division and space-division multiplexing. The TMC-HOF has three triangular cores, and each core has three modes: LP<SUB>01</SUB> and two split LP<SUB>11</SUB> modes. The asymmetric structure of the triangular core can split the LP<SUB>11</SUB> modes. Using the proposed structures, nine independent modes can propagate in a fiber. We use a fully vectorial finite-element method to estimate effective index, chromatic dispersion, differential group delay (DGD), and confinement loss by controlling the parameters of the TMC-HOF structure. We confirm that the proposed TMC-HOF shows flattened chromatic dispersion, low DGD, low confinement loss, low core-to-core crosstalk, and low crosstalk between adjacent modes. The proposed TMC-HOF can provide a common platform for MDM and SDM applications.

Two Years after the <i>Hebei Spirit</i> OilSpill: Residual Crude-Derived Hydrocarbons and Potential AhR-MediatedActivities in Coastal Sediments

Hong, Seongjin,Khim, Jong Seong,Ryu, Jongseong,Park, Jinsoon,Song, Sung Joon,Kwon, Bong-Oh,Choi, Kyungho,Ji, Kyunghee,Seo, Jihyun,Lee, Sangwoo,Park, Jeongim,Lee, Woojin,Choi, Yeyong,Lee, Kyu Tae,Kim, AmericanChemical Society 2012 Environmental science & technology Vol.46 No.3

<P>The <I>Hebei Spirit</I> oil spill occurredin December2007 approximately 10 km off the coast of Taean, South Korea, on theYellow Sea. However, the exposure and potential effects remain largelyunknown. A total of 50 surface and subsurface sediment samples werecollected from 22 sampling locations at the spill site in order todetermine the concentration, distribution, composition of residualcrudes, and to evaluate the potential ecological risk after two yearsof oil exposure. Samples were extracted and analyzed for 16 polycyclicaromatic hydrocarbons (PAHs), 20 alkyl-PAHs, 15 aliphatic hydrocarbons,and total petroleum hydrocarbons using GC-MSD. AhR-mediated activityassociated with organic sediment extracts was screened using the H4IIE-<I>luc</I> cell bioassay. The response of the benthic invertebratecommunity was assessed by mapping the macrobenthic fauna. Elevatedconcentrations of residual crudes from the oil spill were primarilyfound in muddy bottoms, particularly in subsurface layers. In general,the bioassay results were consistent with the chemistry data in adose-dependent manner, although the mass-balance was incomplete. Moreweathered samples containing greater fractions of alkylated PAHs exhibitedgreater AhR activity, due to the occurrence of recalcitrant AhR agonistspresent in residual oils. The macrobenthic population distributionexhibits signs of species-specific tolerances and/or recolonizationof certain species such as <I>Batillaria</I> during weatheringperiods. Although the <I>Hebei Spirit</I> oil spill wasa severe oil exposure, it appears the site is recovering two yearslater.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/esthag/2012/esthag.2012.46.issue-3/es203491b/production/images/medium/es-2011-03491b_0001.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/es203491b'>ACS Electronic Supporting Info</A></P>