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31.
Fisheries Science - The aim of this study was to evaluate the antibacterial properties of oyster, hard clam, and sea urchin shell powders as a result of calcination. After subjection to calcination... 相似文献
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Kwangho Choi Chung Il Lee Kwangseok Hwang Sang-Woo Kim Jong-Hwa Park Yeong Gong 《Fisheries Research》2008,91(2-3):281-290
Data on squid catches of Korean and Japan, water temperatures at depth of 100 m, and night-visible images of fishing boats collected in the East (Japan) Sea from 1970 to 1999 were analyzed to examine the distribution and migration of the Japanese common squid, Todarodes pacificus, in the southwestern part of the East (Japan) Sea. The main fishing grounds detected from squid catch in each grid (0.5° latitude × 0.5° longitude) by Korean squid fishery and night-visible images provided by the Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) were situated in the southwestern part of the East (Japan) Sea. The distribution and migration route was illustrated from squid catch in each grid and DMSP OLS image. In years of high catches, the fishing grounds were situated mainly between Ulleung Island and the eastern coastal waters of Korea, while in years of low catches they were situated between Ulleung Island and the Yamato Bank in the central East (Japan) Sea. The center of fishing activity began moving northward from around the Korea/Tsushima strait to the northern boundary of the Tsushima Warm Current in March, reaching into the Yamato Bank in September, and then returning to the strait by February. The northward and southward migration routes differed; the northward migration route occurred closer to the mainland coast of Korea than the southward migration route did. This work suggests T. pacificus begin their northward migration almost 2 months earlier than previously suggested. 相似文献
34.
Jie-Min Lee Tsorng C. Hwang 《Aquaculture Economics & Management (Blackwell Science)》2013,17(1):47-57
ABSTRACT Policy decisions on what aquaculture products to develop require information on consumer demand for cultured species. However, information on the structure of demand for aquaculture products is limited and what few studies there are in Taiwan, where aquaculture is a major industry, suffer from methodological problems. To clear up some of these problems, we used modified nonnested testing techniques and performance forecasting to determine which generalized models could best estimate the demand for Taiwanese aquaculture products. The results of modified nonnested testing of the aquaculture demand system showed that prices predetermined and quantities predetermined could be used to estimate demand. The generalized ordinary demand model was able to better forecast performance than the generalized inverse demand model. We used the likelihood ratio test to discriminate among the four competing models for the generalized ordinary model; the AIDS model could be more suitably applied to the data. A more general model that is able to incorporate different dynamic structures (partial adjustment, first autoregressive, and static). This general framework is applied to the AIDS model. The first autoregressive AIDS model we used to calculate the own and cross-price elasticities for milkfish, tilapia, shrimp, shellfish, and carps found that price elasticities varied across fish type, that some products had high long-run own price elasticities, and that the demand for aquaculture products was largely determined by inertia. 相似文献
35.
Kim KS Kang HJ Hwang IK Hwang HG Kim TY Choi HC 《Journal of agricultural and food chemistry》2005,53(7):2600-2608
The ultrastructure of cooked and malt-treated cooked rice of Ilpumbyeo (IP) and its mutant Goami 2 (G2), which have extreme contrasts in physicochemical properties, cooking quality, and ultrastructural characteristics in raw grains (1, 2), was compared. In cooked rice of IP, starch granules in endosperm cells were evenly coalesced, appearing as homogeneously smooth sheetlike matrix and/or globules, whereas those in G2 were a heterogeneously coarse matrix in which a novel structural feature, the microfilaments, was embedded. In malt-treated cooked rice of IP, most starch was hydrolyzed by the malt enzymes, appearing as empty vacuoles surrounded by the cell wall, whereas that in G2 was highly resistant to malt treatment, remaining as distinct structural features, the malt-resistant compound starch granules. The property of G2's compound starch granules, which are tolerant of mechanical and chemical treatments thereby retaining their structural integrity (2) and of cooking and malt treatment thereby retaining their physical hardness, appears to play a major role in determining the quality of cooked rice of G2. 相似文献
36.
Lee JE Lee BJ Hwang JA Ko KS Chung JO Kim EH Lee SJ Hong YS 《Journal of agricultural and food chemistry》2011,59(19):10579-10585
The dependence of global green tea metabolome on plucking positions was investigated through (1)H nuclear magnetic resonance (NMR) analysis coupled with multivariate statistical data set. Pattern recognition methods, such as principal component analysis (PCA) and orthogonal projection on latent structure-discriminant analysis (OPLS-DA), were employed for a finding metabolic discrimination among fresh green tea leaves plucked at different positions from young to old leaves. In addition to clear metabolic discrimination among green tea leaves, elevations in theanine, caffeine, and gallic acid levels but reductions in catechins, such as epicatechin (EC), epigallocatechin (EGC), epicatechin-3-gallate (ECG), and epigallocatechin-3-gallate (EGCG), glucose, and sucrose levels were observed, as the green tea plant grows up. On the other hand, the younger the green tea leaf is, the more theanine, caffeine, and gallic acid but the lesser catechins accumlated in the green tea leaf, revealing a reverse assocation between theanine and catechins levels due to incorporaton of theanine into catechins with growing up green tea plant. Moreover, as compared to the tea leaf, the observation of marked high levels of theanine and low levels of catechins in green tea stems exhibited a distinct tea plant metabolism between the tea leaf and the stem. This metabolomic approach highlights taking insight to global metabolic dependence of green tea leaf on plucking position, thereby providing distinct information on green tea production with specific tea quality. 相似文献
37.
Utilization of biochar impregnated with anaerobically digested slurry as slow‐release fertilizer 下载免费PDF全文
We examined the possibility of an environment‐friendly slow‐release fertilizer (SRF) made of biochar impregnated by anaerobically digested slurry. The biochar materials were produced from three types of feedstocks (orange peel, residual wood, water‐treatment sludge) at different temperatures of 300°C, 500°C, and 700°C via pyrolysis. The release behaviors of the water‐soluble K+, Ca2+, and Mg2+ were similar for all impregnated biochars and the commercial SRF used. The water‐retention capacity was greatly improved by mixing the biochar‐SRF with the soil. The yield of lettuce was lower for the biochar‐SRF applications of 3.7 to 34.2 t ha–1 than for the commercial SRF application of 51.4 t ha–1. This might be due to excessive increase of soil pH for the biochar‐SRF application. Based on these results, the authors concluded that the biochar impregnated with nutrients could become an effective slow‐release K+ fertilizer. 相似文献
38.
本研究通过调查苏氨酸与赖氨酸的比率对猪生长性能、表观可消化能和血液尿素氮 (BUN)浓度的影响 , 估测生长阉公猪和小母猪所需最佳苏氨酸与赖氨酸的比率 . 试验采用 150头杂交猪 (长白×约克夏×杜洛克 , 平均体重为 16.75± 0.45 , 其中阉公猪 75头 , 小母猪 75头 ), 按 2× 3析因设计 , 随机分成 6个处理 阉公猪日粮含赖氨酸 1.12% , 按苏氨酸与赖氨 酸比率为 50% 、 60% 和 70% 分成 3个处理 小母猪日粮含赖氨酸 1.33% , 按苏氨酸与赖氨酸比 率为 50% 、 60% 和 70% 分成 3个处理 . 经整个试验期 (体重从 16至 56 ). 在平均日增重、平均 日采食量和饲料转化率方面 , 动物性别和苏氨酸与赖氨酸比率之间无相互影响 . 在生长性能 方面 , 有明显的性别影响 与小母猪相比 , 阉公猪表现出较好的生长性能 , 消耗较多的饲料 (P< 0.01)以及生长的较快 (P< 0.01). 随着苏氨酸与赖氨酸比率的增大 , 阉公猪的 ADG和 FCR有增加的倾向 , 但差异不显著 . 在除粗灰分 (CA)外的可消化性养分方面 , 动物性别和苏氨 酸与赖氨酸比率之间无相互影响 . 在性别之间 , 除小母猪对钙具有较高的可消化性 (P< 0.01)外 , 可消化性养分没有存在的差异 . 而日粮苏氨酸与赖氨酸比率对可消化性养分无影响 . 可消化性必需氨基酸 (EEA)、非必需氨基酸 (NEAA)和总氨基酸 (TTA)的平均值没有受到性别 和苏氨酸与赖氨酸比率的影响 . 没有发现性别和日粮中苏氨酸与赖氨酸比率相互影响的证据 . 在性别之间 , 小母猪的总 BUN浓度比阉公猪低 (P< 0.05). 可以得出结论 " 阉公猪日粮 (赖氨 酸水平为 1.12% )中 , 苏氨酸与赖氨酸比率为 70% , 小母猪日粮 (赖氨酸水平为 1.33% )中 , 苏 氨酸与赖氨酸比率为 60% , 较其它比率的苏氨酸与赖氨酸 , 分别获得较好的生长性能、养分 利用和较低的 BUN浓度 . 相似文献
39.
Kim JH Sohn HJ Hwang WS Hwang EK Jean YH Yamane I Kim DY 《Veterinary parasitology》2000,90(1-2):147-154
The brains of nine aborted bovine fetuses and two newborn calves born from dams suspected to be infected with Neospora caninum were homogenized and inoculated into Vero cells. All fetuses and calves were from cows determined as seropositive to N. caninum by an IFA test. Sera and thoracic fluids of all fetuses and calves also revealed high antibody titer to N. caninum by IFAT ranging from 1:800 to 1:3200. N. caninum was isolated from the brains of one aborted fetus and one newborn calf when the brain homogenates were grown continuously in Vero cell culture. N. caninum tachyzoites, giemsa-positive, were first observed on Days 45 and 56 postinoculation in the newborn calf and the aborted fetus, respectively. The isolates (KBA-1 and KBA-2) were morphologically and ultrastructurally similar to previously published Neospora isolates. The isolated parasites were confirmed as N. caninum by means of the antigenic reactivities, immunostaining, PCR and southern blotting, and electron microscopy. 相似文献
40.
Suk Nam KANG Gyo Moon CHU Young Min SONG Sang Keun JIN In Ho HWANG Il Suk KIM 《Animal Science Journal》2012,83(3):245-251
The effect of by‐products of oriental medicinal plants (OMP; T1) containing 0.03% herb extracts (T2) or 0.1% aminolevulinic acid (T3) on the production performance of swine during the finishing period and on its meat quality were investigated. No significant differences were found in the weight gain, feed intake and feed conversion rate among the tested groups (P > 0.05). But the treated group showed higher (P < 0.05) moisture and ash and lower protein than the control group. The T3 group showed a lower meat cholesterol content (38.42 mg/100 g) compared to the other groups (P < 0.05). The vitamin E content of the muscle in the treated groups was higher compared to the control group. No antibiotic content was detected in all treated and control samples. The values of the volatile basic nitrogen (VBN) and thiobarbituric acid reactive substance (TBARS) of the treated groups were significantly lower (P < 0.01) than the control group. The treated groups had significantly better (P < 0.05) sensory‐test scores for color, flavor, off‐flavor and total acceptability compared to the control group. 相似文献