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71.
72.
Mediha Yildirim‐Aksoy Chhorn Lim Richard Shelby Phillip H Klesius 《Journal of the World Aquaculture Society》2009,40(1):76-86
Growth performance, immune responses and disease resistance were studied in juvenile channel catfish, Ictalurus punctatus, fed a commercial diet (35.3% crude protein and 5.6% lipid) supplemented with menhaden fish oil at levels of 0, 3, 6, and 9% for 15 wk. Dietary fish oil levels did not significantly influence growth performance of catfish. Fatty acid compositions of whole‐body and liver reflected dietary fatty acid composition. No differences were found in hematological values, except that fish fed the 9% fish oil diet had significantly lower hematocrit. The resistance of erythrocytes to hemolysis in hypotonic solutions increased with increasing fish oil levels and the highest resistance was seen with the 9% fish oil diet. Fish fed 6 and 9% added fish oil diets had significantly higher serum protein levels than that of control fish. Serum lysozyme activity of fish fed 3 and 6% added fish oil diet was significantly higher than that of the control. Complement activity and chemotaxis ratio significantly decreased in fish fed diets with 6 or 9% added fish oil. The 3% added fish oil diet, however, had significantly highest natural hemolytic complement activity. Mortality from Edwardsiella ictaluri 14 d postchallenge and antibody titers to E. ictaluri did not differ among treatments. 相似文献
73.
Corn starch was extruded with a corotating twin-screw extruder (24:1 L/D ratio, 31-mm screw diameter) and supercritical CO2 was injected as a blowing agent. The effects of barrel temperature (80–90°C), screw speed (150–250 rpm), and water injection (30–54 g/min) on specific mechanical energy (SME) input for the process and the physical properties of extrudates, such as expansion ratio, water absorption (WA), water solubility (WS), breaking stress, and elastic modulus, were examined using a response surface methodology. Barrel temperature had the greatest effect on physical properties of extrudates but not on SME input, whereas screw speed and water injection had significant effects on SME input. Extrudates had a smooth surface, and air cells were uniform and closed, providing low WA and WS. Using superimposed contour plots, optimum barrel temperature, screw speed, and water injection rate, based on maximum expansion ratio and minimum SME input, were 94–96°C, 155–175 rpm, and 36–39 g/min, respectively. 相似文献
74.
Mechanical and Thermal Sensory Testing in Normal Chondrodystrophoid Dogs and Dogs with Spinal Cord Injury caused by Thoracolumbar Intervertebral Disc Herniations 下载免费PDF全文
75.
M. Syukran Alhelmy Seri Buana Pooria Pasbaskhsh Kheng Lim Goh Farshid Bateni Mas Rosemal Hakim Mas Haris 《Fibers and Polymers》2013,14(4):623-629
A comparative analysis of the elasticity, microstructure and thermal stability of fibres (thickness ranging from 43.4 to 189.4 µm) isolated from pineapple leaves (PALF), coconut coir (COIR), banana leaf-stem (BAN) and oil palm empty fruit bunch (OPEFB) reported in this study. Statistical analysis of the mechanical properties derived from tensile test to rupture reveals significant differences (P<0.05) in the fibre strength (σ), stiffness (E) and extensibility (parameterized by the strain to rupture, ?). It is observed that COIR fibres yield the smallest strength, σ (=99.8±22.5 MPa), and stiffness, E (= 0.5±0.1 GPa), while PALF fibres yield the largest σ (=639.5±301.6 MPa) and E (=7.1±3.1 GPa); PALF fibres exhibit the smallest ? (=0.11±0.03) but OPEFB fibres yield the largest ? (=2.0±1.3). From scanning electron micrographs, it is observed that cellulose fibril rupture predominates in OPEFB, COIR and BAN fibres; a large proportion of the cellulose fibrils fail by pullout in PALF fibres. Thermogravimetric analysis reveals that all fibres are thermally stable up to 250 °C; the fibre residue ranges from 30 to 80 wt% after heating to 500 °C. In particular, BAN experiences the highest weight loss and PALF experiences the lowest weight loss. The findings lend to a simple approach for determining the performance of the composites by assessing the type of natural fibres for reinforcing polymeric matrices. 相似文献
76.
Soek-In Yun Sang-Sun Lim Gwang-Sung Lee Sang-Mo Lee Han-Yong Kim Hee-Myong Ro Woo-Jung Choi 《Biology and Fertility of Soils》2011,47(6):607-617
Nitrogen isotope abundance (?? 15N) of paddy rice (Oryza sativa L.) grown for 110?days after transplanting (DAT) under field conditions with ammonium sulfate (AS with ?0.4?? as a synthetic fertilizer), pig manure compost (PMC with 15.3?? as a livestock manure compost), and hairy vetch (HV with ?0.5?? as a green manure) was investigated to test the possible use of ?? 15N technique in discriminating organically grown from conventionally grown rice. At 15 DAT, the ?? 15N of whole rice decreased (P?<?0.05) in the order of 10.5?? for PMC > 5.5?? for control (without N input) > 4.0?? for HV > 1.8?? for AS. This difference seemed to reflect primarily the ?? 15N signal of N sources. Although differences in ?? 15N of rice grown with isotopically distinct N inputs (i.e. PMC vs. AS and PMC vs. HV) became smaller over time, the difference (2.8 and 3.0?? difference at harvest on 110 DAT, respectively) was still significant (P?<?0.05). However, there was no distinguishable difference between AS and HV treatment after 42 DAT. Such effect of N inputs on ?? 15N of whole rice was also observed for root, shoot, and grain at harvest. Therefore, our study suggests that it is possible to distinguish rice grown with manure composts from that grown with synthetic fertilizers. However, if green manure of preceding N2-fixing plants is used as the N source, ?? 15N of rice may not be a good surrogate of N sources. 相似文献
77.
Kai‐Min Niu Sanaz Khosravi Damini Kothari Woo‐Do Lee Bong‐Joo Lee Sang‐Gu Lim Sang‐Woo Hur Sang‐Min Lee Soo‐Ki Kim 《Journal of the World Aquaculture Society》2021,52(1):244-261
A 12‐week feeding trial was designed to assess the probiotic potential of indigenous Bacillus amyloliquefaciens and/or Bacillus subtilis singly or in combination with Bacillus licheniformis in an extruded feed for olive flounder (Paralichthys olivaceus) juveniles. A high fish meal (FM) diet (control) and a low‐FM diet containing an alternative protein blend (30% FM replacement, FM30) were formulated. Three other experimental diets were prepared by inclusion of B. amyloliquefaciens (BA), B. subtilis (BS), or a mixture of B. amyloliquefaciens, B. subtilis, and B. licheniformis (BASL) into FM30 diet, with a final concentration of 106 CFU/g diet. Results indicated that the FM30 diet was well tolerated by flounder, and the overall performance was not affected by dietary treatments. Lysozyme activity and total immunoglobulin level were significantly reduced in flounders when fed with the FM30 diet compared with the BASL and BA diets, respectively. The Bacillus additives neither enriched the relative abundance of the corresponding Bacillus spp. in the relevant gut microbiota of olive flounder nor modulated the presumptive gene functions of the gut microbiome. Despite the absence of growth‐promoting effect, the tested probiotics could still be economically viable for use as immunostimulants in commercial flounder diets with partial FM replacement. 相似文献
78.
Gunzo Kawamura Teodora Uy Bagarinao Annita Seok Kian Yong Aishah Binti Faisal Leong-Seng Lim 《Fisheries Science》2018,84(2):365-371
Colour vision depends on sufficient ambient light and becomes ineffective at a particular low light intensity. It is not known how decapod crustaceans see colour in dim light. In the present study we investigated the colour vision threshold in larvae of the giant freshwater prawn Macrobrachium rosenbergii in a tank under natural illumination. Plastic beads of different colours (blue, red, yellow and white) in various combinations were suspended in the tank. The larvae swam straight toward the beads and gathered around them. The number of larvae was highest on the blue and white beads. The luminance in the tank was then gradually decreased by covering it with different numbers of layers of black cloth, and the response of the larvae to the beads was video-recorded under infrared illumination. The preference for blue and white beads remained manifest as the luminance was reduced from 418 to 0.07 cd/m2, but not at 0.02 cd/m2, indicating a colour vision threshold between 0.07 and 0.02 cd/m2. The larvae have apposition compound eyes with large optical parameters, comparable to those of apposition eyes of nocturnal insects, which presumably capture more light and show enhanced sensitivity, enabling the larvae to see colour in dim light. 相似文献
79.
Michelle Wen San Lim Kar Mem Tan Lye Yee Chew Kin Weng Kong 《Journal Of Aquatic Food Product Technology》2018,27(4):446-463
Two-level full factorial design was employed to identify the extraction parameters that can improve the derivation of fucoxanthin content (FC), total carotenoid content (TCC), and antioxidant from two brown seaweeds, Sargassum siliquosum (SS) and Sargassum polycystum (SP). These parameters included temperature (A: 4–45°C), time (B: 30–1,440 min), and solvent-to-solid ratio (C: 10–50 ml/g). Antioxidant activities were determined as trolox equivalent antioxidant capacity (TEAC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity, and ferric-reducing antioxidant power (FRAP). Results showed that all three factors were significant (p < 0.05) in providing higher FC in both species. These factors were also significant in obtaining higher TCC in SS; whereas in SP, TCC was only affected by solvent-to-solid ratio. Only temperature was found to contribute significantly to a higher TEAC in both species. However, none of the factors improved DPPH for SS, except temperature and time for SP. For SS, only time was significant in obtaining higher FRAP; whereas temperature and time were significant for SP. Hence, results indicate that a simple modification in the extraction temperature, time, and solvent-to-solid ratio will be able to improve the derivation of fucoxanthin, carotenoids, and antioxidant activities. 相似文献
80.
Jinho Park Sung Chan Lim Jong Sung Won Seung Goo Lee Wan Gyu Hahm Jong Kyoo Park Young Gyu Jeong 《Fibers and Polymers》2016,17(6):827-835
We report the isothermal and non-isothermal crystallization kinetics and associated transcrystalline morphological features of polyarylate(PAR)/nylon6 islands-in-a-sea fibers, where 74 PAR islands serve as reinforcing fibers and nylon6 sea component acts as a semicrystalline matrix in final thermoplastic composites. The temperature-dependent polarized optical microscopic images obtained during a cooling process exhibit that the melt-crystallization is dominated by the interfacial crystallization of nylon6 on the surface of PAR fibers, leading to developing a transcrystalline structure. From the isothermal and non-isothermal melt-crystallization analyses of the islands-in-a sea fiber by using differential scanning calorimetry and the Avrami equation, the overall crystallization rates of the nylon6 sea component in the islands-in-a-sea fiber are found to be highly accelerated by the heterogeneous nucleating effect of the PAR island fibers. In addition, it is revealed that the isothermal and non-isothermal melt-crystallization kinetics of the nylon6 in the islands-in-a-sea fibers consists of two different mechanisms of the primary crystallization owing to the interfacial crystallization and the secondary crystallization due to the bulk crystallization. 相似文献