• ALGAE
• /
• 제30권1호
• /
• pp.49-58
• /
• 2015

In September 2007, reports of respiratory irritation and fish kills were received by the Florida Fish and Wildlife Conservation Commission (FWC) from the Jacksonville, Florida area. Water samples collected in this area indicated a bloom of Karenia brevis, the dinoflagellate that produces brevetoxin, which can cause neurotoxic shellfish poisoning. For the next four months, K. brevis was found along approximately 400 km of coastal and Intracoastal waterways from Jacksonville to Jupiter Inlet. This event represents the longest and most extensive red tide the east coast of Florida has experienced and the first time Karenia species other than K. brevis have been reported in this area. This extensive red tide influenced commercial and recreational shellfish harvesting activities along Florida's east coast. Fourteen shellfish harvesting areas (SHAs) were monitored weekly during this event and 10 SHAs were closed for an average of 53 days due to this red tide. The length of SHA closure was dependent on the shellfish species present. Interagency cooperation in monitoring this K. brevis bloom was successful in mitigating any human health impacts. Kernel density estimation was used to create geographic extent maps to help extrapolate discreet sample data points into $5km^2$ radius values for better visualization of the bloom.

• Asian-Australasian Journal of Animal Sciences
• /
• 제18권6호
• /
• pp.873-878
• /
• 2005

Emissions of nitrous oxide (N$_2$O) and methane (CH$_4$) from poultry enteric fermentation were investigated using a respiration chamber. Birds were placed in a respiration chamber for certain intervals during their growing period or for the whole life cycle. The accumulated gas inside the chamber was sampled and analyzed for N$_2$O and CH$_4$ production. A curve for gas production during a life cycle was fitted. The calculated area under the curve estimated the emission factor of poultry enteric fermentation on a life cycle basis (mg bird$^{-1}$ life cycle$^{-1}$). This method can be used to estimate CH$_4$ or N$_2$O emissions from different types of avian species taking into account factors such as diet, season or thermal effects. The CH$_4$/N$_2$O emission factors estimated for commercial broiler chickens, Taiwan country chickens and White Roman Geese were 15.87/0.03, 84.8/16.4 and 1,500/49 (mg bird$^{-1}$ life cycle$^{-1}$), respectively, while the calculated CH$_4$/N$_2$O emission from enteric fermentations were 3.03/0.006, 14.73/2.84 and 9.5/0.31 (Mg year$^{-1}$), respectively in Taiwan in the year of 2000. The described method is applicable to most poultry species and the reported emission factors were applicable to meat type poultry only.

• 한국가구학회지
• /
• 제24권4호
• /
• pp.345-349
• /
• 2013

Yellow poplar is well known commercial hardwood species in the world because of its availability, rapid growth, large size, excellent form, early natural pruning, and the good working quality of the wood. Therefore, yellow poplar (Liriodendron tulipifera L.) has been adopted in South Korea for decades ago, and its cultivating the saplings and silvicultural system have been studied. However, yellow poplar is still embroiled in controversy for utilization of use and worth. This species has not only advantages such as lower weight, light color, and higher machinability and bending processing, but also has disadvantages which are bad smell and different colors on heartwood and sapwood. In this study, the objective was that use of yellow poplar board as furniture materials by drying and painting process. Thirty years old yellow poplar was cut and dried for 7 days by high-frequency dryness. Adjustment of color tone to walnut color was conducted with multiple colorants and various number of spread times. Uniform color of yellow poplar on heartwood and sapwood was accomplished by applying 1 time stain (green), 2 times transparent primer, 1 time middle-painting (walnut), and 2 times top-painting (walnut) in sequentially. The painted yellow poplar board was used to manufacture table and dressing table. During the furniture manufacture process, no critical issues were occurred on part of jointing and painting. This painting method may be useful data for future use of yellow poplar as furniture materials.

• 수산해양기술연구
• /
• 제22권1호
• /
• pp.6-10
• /
• 1986

우리 나라 주변어장에서의 주요 어자원중 조기류가 수동어탑을 위한 대표적 어종으로 부각되었다. 음원수준을 150~180dB로 가정했을 때 선배열 형의 수동어탐기에 탐지될 수 있는 거리는 최저 3km에서 최대 20km 이상으로 추정되어 어탐거리의 획기적 증대가 기대된다. 뿐만 아니라 조기류가 내는 700~800Hz 사이의 tocal noise의 특성은 수동형 어탐기에 의한 어종식별 거리 및 정밀도를 보다 향상시킬 것임이 분명하다. 다만, 이 수동소나를 조기류외에 대형어군을 이루는 멸치, 칼치, 명태류, 쥐취류, 오징어 등에 적용 여부를 가늠하기에는 보다 많은 정량적 자료가 수집된 연후에 가능할 것으로 믿어진다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제29권12호
• /
• pp.1688-1695
• /
• 2016

The maternally inherited mitochondrial DNA (mtDNA) D-loop region is widely used for exploring genetic relationships and for investigating the origin of various animal species. Currently, domestic ducks play an important role in animal protein supply. In this study, partial mtDNA D-loop sequences were obtained from 145 samples belonging to six South-East Asian duck populations and commercial duck population. All these populations were closely related to the mallard duck (Anas platyrhynchos), as indicated by their mean overall genetic distance. Sixteen nucleotide substitutions were identified in sequence analyses allowing the distinction of 28 haplotypes. Around 42.76% of the duck sequences were classified as Hap_02, which completely matched with Anas platyrhynchos duck species. The neighbor-joining phylogenetic tree also revealed that South-East Asian duck populations were closely related to Anas platyrhynchos. Network profiles were also traced using the 28 haplotypes. Overall, results showed that those duck populations D-loop haplotypes were shared between several duck breeds from Korea and Bangladesh sub continental regions. Therefore, these results confirmed that South-East Asian domestic duck populations have been domesticated from Anas platyrhynchos duck as the maternal origins.

• 대한기계학회논문집B
• /
• 제28권12호
• /
• pp.1632-1639
• /
• 2004

Numerical calculation has been performed to investigate the transport phenomena in the horizontal reactor which has two different gas inlets for MOCVD(metalorganic chemical vapor deposition). The full elliptic governing equations for continuity, momentum, energy and chemical species are solved by using the commercial code FLUENT. It is investigated how thermal characteristics, reactor geometry, and the operating parameters affect flow fields, mass fraction of each reactants. The numerical simulations demonstrate that flow rate of each species, inlet geometry of the reactor, and its distance from the susceptor as well as the inclination of upper wall of reactor can be used effectively to optimize reactor performance. The commonly used idealized boundary conditions are also investigated to predict flow phenomena in the actual deposition system.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
• /
• pp.339.1-339.1
• /
• 2014

In this paper we studied the application of inter-poly dielectric as silicon dioxide-like film was deposited by the higher energy assisting deposition (HEAD) process the modified CCP process, which enables low temperature (LT) process and improving film density. In these experiments the relative hydrogen concentration of $SiO_2$-like films deposited on silicon substrate were analyzed by the secondary ion mass spectroscopy (SIMS) and it was shown that our lower hydrogenated oxide (LHO) film prepared by HEAD process with the precursor contained the siloxane species had lower hydrogen concentration, $8{\times}10{\cdot}^{22}cm{\cdot}^3$ than that of the commercial undoped silicon glass (USG) film ($1{\times}10{\cdot}^{21}cm{\cdot}^3$) prepared by the high density plasma-chemical vapor deposition (HDP-CVD). We consider that the LHO film deposited by HEAD process used as high performance material into Flash memory devices.

• The Plant Pathology Journal
• /
• 제29권1호
• /
• pp.10-16
• /
• 2013

Hevea brasiliensis is a natural source of rubber and an important plantation tree species in Malaysia. Leaf blight disease caused by Fusicoccum substantially reduces the growth and performance of H. brasiliensis. The aim of this study was to use a combination of both morphological characteristics and molecular data to clarify the taxonomic position of the fungus associated with leaf blight disease. Fusicoccum species were isolated from infected leaves collected from plantations at 3 widely separated locations - Selangor, Perak, and Johor states - in Peninsular Malaysia in 2010. All the isolates were identified according to their conidial patterns and DNA sequences generated from internal transcribed spacers (ITS1 and ITS2), the 5.8S rRNA, and an unknown locus (BotF15) containing microsatellite repeats. Based on taxonomic and sequence data, Neofusicoccum ribis was identified as the main cause of leaf blight disease in H. brasiliensis in commercial plantations in Malaysia. A pathogenicity trial on detached leaves further confirmed that N. ribis causes leaf blight disease. N. ribis is an important leaf pathogen, and its detection in Malaysia has important implications for future planting of H. brasiliensis.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제15권3호
• /
• pp.7-14
• /
• 2010

Ecological Risk Assessment (ERA) supports a decision-making process such as establishment of environmental quality criteria. Soil quality criteria (SQC) are essential to protect soil organisms from the exposure to various soil contaminants. In this study, ERA methodologies of advanced countries for soil pollution were extensively compared to propose the ERA approach suitable for soil ecosystem in Korea. The soil ERAs in European Chemical Bureau(ECB), The Netherlands, and Canada can be classified as deterministic ecological risk assessment (DERA), and probabilistic ecological risk assessment (PERA) based on species sensitivity distribution (SSD). We propose three ERA methods according to abundance and reliability of soil ecotoxicity data. The method considered land use such as residential/agricultural, and industrial/commercial uses. The taxonomic groups of soil organism were classified as 'Class' level including different trophic levels (Magnoliopsida or Liliopsida, Clitellata, and Insecta or Secernentea). This study can be used to estimate the soil quality criteria to protect soil biota.

• Mycobiology
• /
• 제34권2호
• /
• pp.73-78
• /
• 2006

Inter-specific hybridization between Pleurotus pulmonarius and P. florida was attempted through PEG-induced protoplast fusion to select a fusant. The protocol for protoplast release, regeneration and fusion in these two Pleurotus species was standardized using the variables controlling the process. The mixture of mycolytic enzymes, i.e. commercial cellulase, crude chitinase and pectinase, KCl (0.6 M) as osmotic stabilizer, pH 6 of the phosphate buffer and an incubation time of 3 hours resulted in the maximum release of protoplasts from 3-day-old mycelia of P. florida ($5.3{\sim}5.75{\times}10^{7}$ protoplasts/g) and P. pulmonarius ($5.6{\sim}6{\times}10^{7}$ protoplasts/g). The isolated protoplasts of P. florida regenerated mycelium with 3.3% regeneration efficiency while P. pulmonarius showed 4.1% efficiency of regeneration. Polyethyleneglycol (PEG)-induced fusion of protoplasts of these two species resulted in 0.28% fusion frequency. The fusant produced fruiting bodies on paddy straw but required a lower temperature of crop running ($24{\pm}2^{\circ}C$) than its parents which could fruit at $28{\pm}2^{\circ}C$. The stable fusant strain was selected by testing for the selected biochemical markers i.e. Carbendazim tolerance and utilization of the lignin degradation product, vanillin.