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81.
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82.
The 23 open reading frame (ORF) 5 sequences of Korean type II porcine reproductive and respiratory syndrome virus (PRRSV) were collected from viremic sera from the (modified live vaccine) MLV-vaccinating and non-vaccinating farms from 2007 to 2008. The samples were phylogenetically analyzed with previous ORF5 sequences, including type I Korean PRRSV, and previously reported or collected sequences from 1997 to 2008. A MN184-like subgroup of type II Korean PRRSV was newly identified in the viremic sera collected from 2007 to 2008. And of the type I PRRSVs, one subgroup had 87.2~88.9% similarity with the Lelystad virus, showing a close relationship with the 27~2003 strain of Spain. The maximum parsimony tree of type II PRRSV from 1997 to 2008 showed that they had evolved to four lineages, subgroups 1, 2, 3 and 4. Most of the recently collected type II PRRSVs belonged to subgroup 4 (48%). The region of three B-cell epitopes and two T-cell epitopes of ORF5 amino acids sequences was considerably different from the MLV in subgroups 3 and 4. In conclusion, the existence of type I PRRSV, which was genetically different from Lelystad virus (Prototype of type I PRRSV), and heterologous type II PRRSVs of viremic pigs detected even in the MLV-vaccinating farms indicated the need for new vaccine approaches for the control of PRRSV in Korea.  相似文献   
83.
Current study investigated the effect of feeding systems (conventional vs organic rearing) on carcass characteristics, meat quality and fatty acid composition of Musculus longissimus dorsi of Korean native black barrows (KNP). Thirty pigs were reared under a conventional feeding system at indoor area of 1 m2 per head, while another thirty pigs were fed an indoor area with organic saw dusts of 1 m2 and an outdoor area with free ranges of 1 m2 for each pig for organic system. Diet for the organic rearing was also provided according to the guideline for organic pork products. Warner–Bratzler shear force was lower and water holding capacity was higher for pork produced under the organic guidelines. However, pork produced by an organic system did not affect sensory traits compared to pork produced by a conventional one. In addition, longissimus muscle from organically reared pigs had significantly (P < 0.05) higher myoglobin content and consequently higher CIE a?-values compared with those for the conventionally-reared pigs (P < 0.05). The organic pork resulted in significantly (P < 0.05) higher polyunsaturated fatty acid (PUFA) and unsaturated fatty acid contents, as well as a higher n-3 PUFA than the conventional one (P < 0.05).  相似文献   
84.
Carbon nanotube (CNT)/magnetite (Fe3O4) nanocomposites were successfully fabricated by nanocoating. When the CNT/Fe3O4 nanocomposites were added to a carbonyl (CI) based magnetorheological fluid (MRF), the magnetic rheological properties of the MRF were enhanced. Such enhancement in magnetic rheological properties of the CI-CNT/Fe3O4 MRF is considered to be attributable to both the superparamagnetic property of the magnetic layer covering the CNT surface and the high length to diameter ratio of the CNT/Fe3O4 nanocomposite. Impact properties for CI-CNT/Fe3O4 MRF treated Kevlar fabrics were also tested, and improved impact properties were observed with external magnetic fields compared to CI-MRF treated Kevlar fabrics.  相似文献   
85.
β-Glucosidase (β-1,4-D-glucoside glucohydrolase: EC.3.2.1.21) catalyzes the hydrolysis of β-glucosidic bonds between saccharides and aryl or alkyl groups. A gene encoding β-glucosidase from Bacillus licheniformis KCTC 1918, an anaerobic spore-forming soil bacterium, was cloned and characterized. The structural gene for the β-glucosidase consists of 1410 bp encoding 469 amino acid residues, and has a molecular weight of 53.4 kDa as estimated by sodium dodecyl sulfate polyacrylamide gel electrophoresis with 12% separating gel. The enzyme activity was determined against pNPG as a substrate. The enzyme was optimally active at pH 6.0 (citrate-phosphate buffer) and 47°C. β-Glucosidase retained 100% of its original activity for 24 h. The activity of the enzyme was stimulated by glycerol and urea and was decreased by Ca2+, Cu2+, Hg2+, Mg2+, and Mn2+. In particular, Cu2+ had the strongest negative effect on β-glucosidase activity. The purified β-glucosidase was active against pNPG and cellobiose. When the β-glucosidase was tested for cellulose hydrolysis, the supplement of β-glucosidase with cellulose increased the glucose yield from pine wood powder by 139.8%.  相似文献   
86.
ABSTRACT

Radiation-specific luminescence properties in irradiated dried-fishery products (pollack, little pollack, clams, and shrimp) were investigated at different dose levels (0–10 kGy). Photostimulated luminescence (PSL) analysis of whole samples was effective for dried clams and shrimp, while low PSL sensitivity was observed in dried pollack and little pollack. Thermoluminescence (TL) analysis was conducted after isolation of silicate minerals, in which the two methods of mineral isolation—density separation and acid hydrolysis—were compared. Irradiated samples were easily distinguishable through the strong TL glow curves, with maximum peaks in temperature range of 150–250°C. TL ratios (TL1/TL2) were < 0.1 for nonirradiated samples, while > 0.1 for irradiated. There was a clear effect of applied irradiation dose, with a negligible effect of the method used for mineral separation. The mineral composition showed that feldspar and quartz minerals were mainly responsible for the well-characterized luminescence behavior upon irradiation.  相似文献   
87.
Kenaf is an economically important crop that contains various functional compounds. The objective of this study was to evaluate the nutritional properties of leaves, stem bark, flowers, and seeds collected from three mutant kenaf cultivars (Jangdae, Baekma, and Jeokbong) and two original cultivars (Jinju and C14). For all analyzed tissues, there were no significant differences in the proximate compositions (moisture, crude protein, crude fiber, crude fat, ash, and nitrogen-free extract) among the tested genotypes, except for the leaf crude protein content, which was highest in Jinju plants. Of the tested minerals, potassium and calcium were the most abundant in all tissues. Additionally, we detected significant differences in the mineral contents (e.g., calcium, phosphorus, potassium, magnesium, zinc, and iron) of various tissues in all cultivars. Proline and phenylalanine were the major amino acids detected in leaves, and the highest total amino acid (TAA) and essential amino acid (EAA) contents were observed in Jinju plants. The TAA and EAA contents were lower in stem bark than in the other tissues, except in Baekma plants, in which the lowest levels were observed in flowers. Moreover, the TAA and EAA contents were approximately 20 times lower in white flowers (Baekma) than in ivory flowers. Furthermore, the highest TAA and EAA concentrations were observed in Jangdae seeds. These results may be useful for identifying the optimal cultivar and tissues for use in food products.  相似文献   
88.
This study examined the effects of road transportation on metabolic and immunological responses in dairy heifers. Twenty Holstein heifers in early pregnancy were divided into non‐transported (NT; n = 7) and transported (T; n = 13) groups. Blood was collected before transportation (BT), immediately after transportation for 100 km (T1) and 200 km (T2), and 24 h after transportation (AT). The T heifers had higher (P < 0.05) blood cortisol and non‐esterified fatty acid concentrations after T1 and T2 than did NT heifers. By contrast, the T heifers had lower (P < 0.05) serum triglyceride concentrations after T1 and T2 than had the NT heifers. The serum cortisol and triglyceride concentrations returned (P > 0.05) to the BT concentrations at 24 h AT in the T heifers. The granulocyte‐to‐lymphocyte ratio and the percentage of monocytes were higher (P < 0.05) after T2 in the T heifers than in the NT heifers, suggesting that transportation stress increased the numbers of innate immune cells. T heifers had higher (P < 0.01) plasma haptoglobin concentrations than NT heifers 24 h AT. In conclusion, transportation increased cortisol secretion and was correlated with increased metabolic responses and up‐regulation of peripheral innate immune cells in dairy heifers.  相似文献   
89.

Purpose

Plant residues are one of the main sources of soil organic matter in paddy fields, and elucidation of the bacterial communities decomposing plant residues was important to understand their function and roles, as the microbial decomposition of plant residues is linked to soil fertility. We conducted a DNA stable isotope probing (SIP) experiment to elucidate the bacterial community assimilating 13-carbon (13C) derived from plant residue under an anoxic soil condition. In addition, we compared the bacterial community with that under the oxic soil condition, which was elucidated in our previous study (Lee et al. in Soil Biol Biochem 43:814–822, 2011).

Materials and methods

We used the 13C-labeled dried rice callus cells as a model of rice plant residue. A paddy field soil was incubated with unlabeled and 13C-labeled callus cells. DNA extracted from the soils was subjected to buoyant density gradient centrifugation to fractionate 13C-enriched DNA. Then, polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) analysis of bacterial 16S rDNA band patterns and band sequencing method were used to evaluate bacterial community.

Results and discussion

DGGE analysis showed that the band patterns in the 13C-enriched fractions were distinctly changed over time, while the changes in the community structure before fractionation were minor. Sequencing of the 13C-labeled DGGE bands revealed that Clostridia were a major group in the bacterial communities incorporating the callus-derived carbon although Gram-negative bacteria, and Actinobacteria also participated in the carbon flow from the callus under the anoxic condition. The proportion of Gram-negative bacteria and Actinobacteria increased on 14 days after the onset of incubation, suggesting that the callus was decomposed by diverse bacterial members on this phase. When the bacterial groups incorporating the 13C were compared between under anoxic and oxic soil conditions, the composition was largely different under the two opposite conditions. However, some members of Gram-negative bacteria were commonly found under the anoxic and oxic soil conditions.

Conclusions

The majority of bacterial members assimilating the callus carbon was Clostridia in the soil under anoxic conditions. However, several Gram-negative bacterial members, such as Acidobacteria, Bacteroidetes, and Proteobacteria, also participated in the decomposition of callus under anoxic soil conditions. Our study showed that carbon flow into the diverse bacterial members during the callus decomposition and the distinctiveness of the bacterial communities was formed under the anoxic and oxic soil conditions.
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90.
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