A simple method for spiking formulated feed with domoic acid (DA) was developed in this study. DA feed was prepared by mixing 0.15 mL 100 μg mL-1 DA with 0.1 g formulated feed, and drying the mixture at room temperat...A simple method for spiking formulated feed with domoic acid (DA) was developed in this study. DA feed was prepared by mixing 0.15 mL 100 μg mL-1 DA with 0.1 g formulated feed, and drying the mixture at room temperature for 2 h. The prepared DA feed contained 0.19 pg DA per particle. Of the added DA, 46.72% was retained in the feed. Relatively high DA retention (about 50%) was recorded after DA feed was soaked in water for 2 h. Exposure to DA feed for 7 d did not cause the increase of tissue DA level of adult king scallop (Pecten maximus) significantly in 60 d. The increase of their gonad index after DA exposure was not significantly different from the control. No significant change in DA level was found in spermary, ovary or fertilized eggs after DA exposure. These results indicated that DA excretion may be more efficient than DA accumulation under the current experimental conditions, and the mechanism of domoic acid incorporation in P. maximus may involve intracellular biotransformation.展开更多
Large diameter fans with low solidity are widely used in automotive application for engine cooling. Their designs with small chord length help reducing the torque on the electrical motor and providing a good aerodynam...Large diameter fans with low solidity are widely used in automotive application for engine cooling. Their designs with small chord length help reducing the torque on the electrical motor and providing a good aerodynamic compromise between several operating conditions, some of these being at high flow rate. Their global performances are measured according to the ISO standard DP 5801, which allows comparison of results from different facilities. However, some variations in global performances are observed when considering results from two different test rigs. On a fan selected for the purpose of this study, up to 6 % of efficiency is lost on the worst case. As efficiency is more than ever a key factor to select a component, some experimental and numerical investigations were conducted to analyze the fan behavior on each facility. Two sets of measurement and simulation are performed and compared. Geometries considered for the domain of computation include the test rig plenum, the torquemeter, the ground and a large domain for the atmospheric conditions. The exact fan geometry with tip clearance and under-hub ribs is also considered. Numerical results show a good agreement with experiment in both cases when convergence is reached and for low flow rate when computations are switched to unsteady mode. Comparisons show that simulations are able to capture the different fan behaviors depending on the confguration and those efficiency losses previously observed are correctly predicted. These results are further analyzed to perform some post-processing. Blade loading remains identical for both cases but disparities appear in the wake and its interaction with the surrounding. Tiny details that are often neglected during experiment and/or simulation appear to be the cause of slight variations. Position of the torquemeter and shape of the plenum are among the parameters that various and that have cumulative effects. Efficiency being a ration of pressure and torque, variations are rather important. Finally, these results are discussed in terms of rules for conception and a new geometry less sensible to loss of efficiency is proposed.展开更多
The effect of acute E. coli challenge on the anti-disease activity of scallops Argopecten irra-dians is examined. The treatments of scallop from which hemolymph samples were taken for study included (1) control scallo...The effect of acute E. coli challenge on the anti-disease activity of scallops Argopecten irra-dians is examined. The treatments of scallop from which hemolymph samples were taken for study included (1) control scallops, (2) sham-injected scallops, (3) PSW-injected scallops and (4) E. coli-injected scallops. From the beginning, the anti-disease activities of scallops are deter -mined at 12 hr and 24 hr.The concentrations of circulating hemocytes, the total serum protein concentrations and the activities of alkaline phosphatase, acid phosphatase and superoxide dismutase in the scallops Argopecten irradians are determined.Injection with E. coli results in a significant elevation in the concentration of circulating hemocytes and in the alkaline phosphatase activity and a significant decline in the total serum protein concentration and in the superoxide dismutase activity at 24 hr postchallenge. It shows that metabolism of bay scallop is expedited to adopt the challenge.展开更多
The cultivation and management of different legume species and their varieties were tested in South-Western Finland at farmers＇ fields in two years, 2010 and 2011. The studied legumes were peas and lava beans, and in...The cultivation and management of different legume species and their varieties were tested in South-Western Finland at farmers＇ fields in two years, 2010 and 2011. The studied legumes were peas and lava beans, and included also such species which are seldom or not normally cultivated in Finland, namely soybeans and blue and white lupins. Seed samples were collected from legume farms. The quality of different legume species was analysed and compared to each others. The chemical qualities were analysed for crude protein, fat, fibre, ash, nitrogen-free extract and phytic acid contents, and amino acid composition. The quality of the varieties of lupins and soybeans were compared to the quality of pea and fava bean varieties, which are generally cultivated nowadays in Finland. The highest protein contents were in soybean （369 and 379 g kg^-1） and white lupin （382 g kg^-1） and the lowest in pea varieties. Amino acid composition of legumes is good, but lupins have lower lysine content （g 100 g^-1 protein） than other legumes. High fat contents were in soybeans （91 and 100 g kg^-1） and white lupin （101 g kgl）, and moderate in blue lupin （30-49 g kg^-1）. Fuego fava bean variety had lower protein content than Kontu. The highest phytic acid contents were in soybeans （18.9 and 22.6 mg kg^-1） and the lowest in white lupin （6.2 mg kg^-1）. Lupins are interesting protein crops, especially white lupin with high protein and fat and low phytic acid contents. Lupins are not day length sensitive, like soybean, and therefore valuable for long-day cultivation conditions The present research strengthens the good chemical quality of legumes for food and feed purposes.展开更多
Hydrogen peroxide(H_2O_2) has its significance during the combustion of heavy hydrocarbons in the internal combustion(IC) engines. Owing to its importance the measurements of H_2O_2 dissociation rate have been reporte...Hydrogen peroxide(H_2O_2) has its significance during the combustion of heavy hydrocarbons in the internal combustion(IC) engines. Owing to its importance the measurements of H_2O_2 dissociation rate have been reported mostly using the shock tube apparatus. These types of experimental measurements are although quite reliable but require high cost. On the other hand, numerical simulations provide low cost and reliable solutions especially using computation fluid dynamics(CFD) software. In the current study an experimental shock tube flow is modeled using open access platform OpenFOAM to investigate the thermal decomposition of H_2O_2. Using two different convective schemes, limited Linear and upwind, the propagation of shock wave and resultant dissociation reaction are simulated. The results of the simulations are compared with the experimental data. It is observed that the rate constant measured using the simulation data deviates from the experimental results in the low temperature range and approaches the experimental values as the temperature is raised.展开更多
文摘A simple method for spiking formulated feed with domoic acid (DA) was developed in this study. DA feed was prepared by mixing 0.15 mL 100 μg mL-1 DA with 0.1 g formulated feed, and drying the mixture at room temperature for 2 h. The prepared DA feed contained 0.19 pg DA per particle. Of the added DA, 46.72% was retained in the feed. Relatively high DA retention (about 50%) was recorded after DA feed was soaked in water for 2 h. Exposure to DA feed for 7 d did not cause the increase of tissue DA level of adult king scallop (Pecten maximus) significantly in 60 d. The increase of their gonad index after DA exposure was not significantly different from the control. No significant change in DA level was found in spermary, ovary or fertilized eggs after DA exposure. These results indicated that DA excretion may be more efficient than DA accumulation under the current experimental conditions, and the mechanism of domoic acid incorporation in P. maximus may involve intracellular biotransformation.
文摘Large diameter fans with low solidity are widely used in automotive application for engine cooling. Their designs with small chord length help reducing the torque on the electrical motor and providing a good aerodynamic compromise between several operating conditions, some of these being at high flow rate. Their global performances are measured according to the ISO standard DP 5801, which allows comparison of results from different facilities. However, some variations in global performances are observed when considering results from two different test rigs. On a fan selected for the purpose of this study, up to 6 % of efficiency is lost on the worst case. As efficiency is more than ever a key factor to select a component, some experimental and numerical investigations were conducted to analyze the fan behavior on each facility. Two sets of measurement and simulation are performed and compared. Geometries considered for the domain of computation include the test rig plenum, the torquemeter, the ground and a large domain for the atmospheric conditions. The exact fan geometry with tip clearance and under-hub ribs is also considered. Numerical results show a good agreement with experiment in both cases when convergence is reached and for low flow rate when computations are switched to unsteady mode. Comparisons show that simulations are able to capture the different fan behaviors depending on the confguration and those efficiency losses previously observed are correctly predicted. These results are further analyzed to perform some post-processing. Blade loading remains identical for both cases but disparities appear in the wake and its interaction with the surrounding. Tiny details that are often neglected during experiment and/or simulation appear to be the cause of slight variations. Position of the torquemeter and shape of the plenum are among the parameters that various and that have cumulative effects. Efficiency being a ration of pressure and torque, variations are rather important. Finally, these results are discussed in terms of rules for conception and a new geometry less sensible to loss of efficiency is proposed.
基金Funded by Projects under the Major State Basic Research Developmet Program(G1999012010)
文摘The effect of acute E. coli challenge on the anti-disease activity of scallops Argopecten irra-dians is examined. The treatments of scallop from which hemolymph samples were taken for study included (1) control scallops, (2) sham-injected scallops, (3) PSW-injected scallops and (4) E. coli-injected scallops. From the beginning, the anti-disease activities of scallops are deter -mined at 12 hr and 24 hr.The concentrations of circulating hemocytes, the total serum protein concentrations and the activities of alkaline phosphatase, acid phosphatase and superoxide dismutase in the scallops Argopecten irradians are determined.Injection with E. coli results in a significant elevation in the concentration of circulating hemocytes and in the alkaline phosphatase activity and a significant decline in the total serum protein concentration and in the superoxide dismutase activity at 24 hr postchallenge. It shows that metabolism of bay scallop is expedited to adopt the challenge.
文摘The cultivation and management of different legume species and their varieties were tested in South-Western Finland at farmers＇ fields in two years, 2010 and 2011. The studied legumes were peas and lava beans, and included also such species which are seldom or not normally cultivated in Finland, namely soybeans and blue and white lupins. Seed samples were collected from legume farms. The quality of different legume species was analysed and compared to each others. The chemical qualities were analysed for crude protein, fat, fibre, ash, nitrogen-free extract and phytic acid contents, and amino acid composition. The quality of the varieties of lupins and soybeans were compared to the quality of pea and fava bean varieties, which are generally cultivated nowadays in Finland. The highest protein contents were in soybean （369 and 379 g kg^-1） and white lupin （382 g kg^-1） and the lowest in pea varieties. Amino acid composition of legumes is good, but lupins have lower lysine content （g 100 g^-1 protein） than other legumes. High fat contents were in soybeans （91 and 100 g kg^-1） and white lupin （101 g kgl）, and moderate in blue lupin （30-49 g kg^-1）. Fuego fava bean variety had lower protein content than Kontu. The highest phytic acid contents were in soybeans （18.9 and 22.6 mg kg^-1） and the lowest in white lupin （6.2 mg kg^-1）. Lupins are interesting protein crops, especially white lupin with high protein and fat and low phytic acid contents. Lupins are not day length sensitive, like soybean, and therefore valuable for long-day cultivation conditions The present research strengthens the good chemical quality of legumes for food and feed purposes.
文摘Hydrogen peroxide(H_2O_2) has its significance during the combustion of heavy hydrocarbons in the internal combustion(IC) engines. Owing to its importance the measurements of H_2O_2 dissociation rate have been reported mostly using the shock tube apparatus. These types of experimental measurements are although quite reliable but require high cost. On the other hand, numerical simulations provide low cost and reliable solutions especially using computation fluid dynamics(CFD) software. In the current study an experimental shock tube flow is modeled using open access platform OpenFOAM to investigate the thermal decomposition of H_2O_2. Using two different convective schemes, limited Linear and upwind, the propagation of shock wave and resultant dissociation reaction are simulated. The results of the simulations are compared with the experimental data. It is observed that the rate constant measured using the simulation data deviates from the experimental results in the low temperature range and approaches the experimental values as the temperature is raised.
