Dietary omega-3 (n - 3) polyunsaturated fatty acids (PUFA) are recommended by public health organizations to reduce the risk of cardiovascular disease, and several epidemiological studies have suggested there is an in...Dietary omega-3 (n - 3) polyunsaturated fatty acids (PUFA) are recommended by public health organizations to reduce the risk of cardiovascular disease, and several epidemiological studies have suggested there is an inverse association between n - 3 intake and human cancers. However, n - 3 are susceptible to an increase in lipid peroxidation in the human body. As part of a crossover dietary intervention study of a diet (20% of energy from fat) with or without an additional 3% of energy from a mixture of n - 3 (with 5.36 g α-linolenic acid and 1.45 g eicosapentaenoic acid and docosahexaenoic acid per 2000 kcal per day), we measured total in vivo lipid peroxidation in healthy postmenopausal women (n = 15). Our results indicated that the diet with 3% of energy from n - 3 significantly increased the urinary concentrations of total polar lipophilic aldehydes and related compounds produced via lipid peroxidation (p α, β-unsaturated hydroxy aldehydes 4-hydroxy-2-trans - hexenal (p trans -decenal (p < 0.05) compared to the diet with less than 1% of energy from n - 3. This is also the first study to document the presence of 4-hydroxy-2-trans -decenal in the urine of individuals consuming n - 3. These results demonstrate that an increase in 3% of energy from dietary n – 3 increases in vivo lipid peroxidation.展开更多
In order to improve the toughness of the cured aromatic tetrafunctional epoxy resins, a dlmer rarboxylic acid named dlmer fatty acid （DFA） was used to modify an aromatic tetrafunctional epoxy, N, N, N＇, N＇-tetragl...In order to improve the toughness of the cured aromatic tetrafunctional epoxy resins, a dlmer rarboxylic acid named dlmer fatty acid （DFA） was used to modify an aromatic tetrafunctional epoxy, N, N, N＇, N＇-tetraglycidyl-2,2-bis [ 4-（ 4-aminophcuoxy ） phenyl ] propane （TGBAPP）. The curing behaviors of DFA- TGBAPP/MNA （ methyl nadic anhydride） systems were studied by differential scanning calorimetry （DSC） method. And the thermal properties of the cured epoxy resin were investigated with the thermo-gravimetric analysis （TGA） and dynamic mechanical analysis （DMA）. Besides, the toughness was characterized with the impact strength tested by charpy impact testing. The results indicated that the modification would improve the curing reactions, and the curing temperatures were decreased with the increasing content of DFA. The thermal properties were not influenced obviously, and the toughness could be improved when the epoxy resin was modified with DFA.展开更多
文摘Dietary omega-3 (n - 3) polyunsaturated fatty acids (PUFA) are recommended by public health organizations to reduce the risk of cardiovascular disease, and several epidemiological studies have suggested there is an inverse association between n - 3 intake and human cancers. However, n - 3 are susceptible to an increase in lipid peroxidation in the human body. As part of a crossover dietary intervention study of a diet (20% of energy from fat) with or without an additional 3% of energy from a mixture of n - 3 (with 5.36 g α-linolenic acid and 1.45 g eicosapentaenoic acid and docosahexaenoic acid per 2000 kcal per day), we measured total in vivo lipid peroxidation in healthy postmenopausal women (n = 15). Our results indicated that the diet with 3% of energy from n - 3 significantly increased the urinary concentrations of total polar lipophilic aldehydes and related compounds produced via lipid peroxidation (p α, β-unsaturated hydroxy aldehydes 4-hydroxy-2-trans - hexenal (p trans -decenal (p < 0.05) compared to the diet with less than 1% of energy from n - 3. This is also the first study to document the presence of 4-hydroxy-2-trans -decenal in the urine of individuals consuming n - 3. These results demonstrate that an increase in 3% of energy from dietary n – 3 increases in vivo lipid peroxidation.
基金Shanghai Leading Academic Discipline Project,China(No.s30107)the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning,Chinathe Project of Shanghai Science and Technology Committee,China(No.12520500300)
文摘In order to improve the toughness of the cured aromatic tetrafunctional epoxy resins, a dlmer rarboxylic acid named dlmer fatty acid （DFA） was used to modify an aromatic tetrafunctional epoxy, N, N, N＇, N＇-tetraglycidyl-2,2-bis [ 4-（ 4-aminophcuoxy ） phenyl ] propane （TGBAPP）. The curing behaviors of DFA- TGBAPP/MNA （ methyl nadic anhydride） systems were studied by differential scanning calorimetry （DSC） method. And the thermal properties of the cured epoxy resin were investigated with the thermo-gravimetric analysis （TGA） and dynamic mechanical analysis （DMA）. Besides, the toughness was characterized with the impact strength tested by charpy impact testing. The results indicated that the modification would improve the curing reactions, and the curing temperatures were decreased with the increasing content of DFA. The thermal properties were not influenced obviously, and the toughness could be improved when the epoxy resin was modified with DFA.
