硒与人体健康

简要地介绍了硒（Se）元素的生理功能以及硒对某些疾病的影响，最后指出人体摄取硒的必需量和安全量。

安全阀动态泄放下火炬模拟研究

海上平台火炬系统计算需要根据不同泄放源的泄放工况进行综合分析,以选取合适的泄放量。由于实际泄放阀选阀尺寸一般高于必需尺寸,导致实际泄放量远大于必需泄放量,而基于安全阀额定泄放量进行火炬系统设计,将增加设备尺度及火炬臂长度。创新性采用HYSYS动态模拟结合Flaresim动态计算方法,得到在安全保护系统作用下火炬泄放量及热辐射的变化趋势,结果证明基于必需泄放量下的火炬长度可以满足火炬安全泄放要求,该技术方法和结论在一定程度上可以用于指导工程实践。

Seasonal biochemical changes in composition of body wall tissues of sea cucumber Apostichopus japonicus

Seasonal variation in proximate, amino acid and fatty acid composition of the body wall of sea cucumber Apostichopus japonicus was evaluated. The proximate composition, except for ash content, changed significantly among seasons （P〈0.05）. Alanine, glycine, glutamic acid and asparagic acid were the most abundant amino acids. Total amino acid and essential amino acid contents both varied clearly with seasons （P〈0.05）. 16：0 and 16：1n7 were the primary saturated fatty acid （SFA） and monounsaturated fatty acid （MUFA） respectively for all months. EPA （20：5n-3）, AA （20：4n-6） and DHA （22：6n-3） were the major polyunsaturated fatty acids （PUFA）. The proportions of SFA and PUFA yielded significant seasonal variations （P〈0.001）, but MUFA did not changed significantly. The results indicated that the biochemical compositions of the body wall in A. japonieus were significantly influenced by seasons and that the body wall tissue is an excellent source of protein, MUFA and n-3 PUFA for humans.

Investigation of Essential or Non-essential Character of Some Hardly Known Trace Elements for Plants

The concentration distribution of essential and non-essential micro-elements of the tissues of healthy organisms shows significant difference. This fact can be used for clarification of the biological role of hardly known trace elements, as well, proving the essential or non-essential character. In case of essential elements the concentration range is rather narrow, the distribution is normal. In case of non-essential elements the interval is wide, the concentration-distribution is log-normal. Measurements and mathematical calculations were carried out for determination of the concentrations and concentration-distributions of some micro-elements, trying to clarify the essentiality or non-essential character of the investigated elements from point of view of plant physiology. Based on the measurements for radish Li and Ni seem to be non-essential trace elements, however in case of Sr the distribution curve suggests an essential character, because the concentration range is not wide.

Body composition and compensatory growth in Nile tilapia Oreochromis niloticus under different feeding intervals

We investigated the growth and body composition of Nile tilapia under five different feeding regimes. A control group was fed to satiation twice daily for 185 days; four treatment groups were fed at intervals of 2, 3, 4 or 7 days(dietary ‘restricted' period, days 0–80) and then fed to satiation(‘refeeding' period, days 80–185). Compensatory growth in weight and length of the feed-restricted groups was observed during the refeeding period. However, the growth of none of the restricted groups caught up with that of the control group over the experimental period. Feed intake upon refeeding increased with the duration of deprivation. There were no significant differences in feed efficiency between the restricted and control groups during the refeeding stage, suggesting that hyperphagia was the mechanism responsible for the increased growth rates during this period. Tilapia preferentially used n-3 polyunsaturated fatty acids and nonessential amino acids during the restricted-feeding period. Higher production was achieved by higher feed consumption. We suggest that if attainment of market size in minimum time is required, fish should be consistently fed to satiation, while taking care to avoid the possible negative consequences of overfeeding.

Comparative study of the nutritional composition and toxic elements of farmed and wild Chanodichthys mongolicus

Information of the difference in quality between farmed and wild fish is central to better ensuring fish products produced in aquaculture meet regulatory and consumer requirements. Proximate composition, amino acid and fatty acid profiles, and toxic elements contents of fanned and wild Chanodichthys mongolicus were established and compared. Significantly higher crude protein content while lower moisture content in farmed fish compared to wild fish were observed （P〈0.05）. The percentages of total amino acids （TAA）, total essential amino acids （TEAA）, total non-essential amino acids （TNEAA） and total delicious amino acids （TDAA） in farmed fish were all significantly higher than those in the wild equivalent （P〈0.05）. Compared to the FAO/WHO recommended reference values, the ratios of TEAA/ TAA （39.84%o-40.33%） were comparable to 40% and TEAA / TNEAA （66.22%-67.60%） were above 60%. Fatty acid profiles in both farmed and wild C. mongolicus were dominated by monounsaturated fatty acid （MUFA）, with farmed fish contained much more MUFA content compared to wild counterpart （P〈0.05）. Notably, wild fish exhibited significantly higher levels of total polyunsaturated fatty acid （PUFA） including eicosapentaenoic acid （EPA） and docosahexaenoic acid （DHA） than fanned fish （P〈0.05）. The EPA （C20：503） and linoleic acid （C18：206） were the predominant PUFA in wild and farmed C. mongolicus, respectively. Moreover, farmed fish displayed an overall lower toxic element levels （As, Cd, Pb and Hg） in comparison with wild fish, and both were far lower than the established limit standard. In conclusion, our results suggest that the nutritional quality of fanned C. mongolicus was inferior to their wild counterpart with respect to fatty acids nutrition, and therefore further studies should focus on the improving C. mongolicus diet in order to enhance the overall nutritional composition.

Effect of germination on the nutritional quality of Pearl millet

Changes in proximate composition, trypsin inhibitor activity, phytic acid, tannins, in vitro protein digestibility and amino acids content of Pearl millet were investigated after germination for 5 days. Germination significantly increased protein content of pearl millet, with a parallel decrease in lipid and carbohydrates. Trypsin inhibitor activity and the phytic acid content showed significant decrease whereas tannin content increased after 5 days germination. In vitro protein digestibility （IVPD） was significantly decreased with germination, suggesting that tannins may be responsible for enzymes inhibition. Amino acid analysis revealed significant increase in essential amino acids and none essential amino acids.

The role of iron homeostasis in remodeling immune function and regulating inflammatory disease

The essential trace element iron regulates a wide range of biological processes in virtually all living organisms.Because both iron deficiency and iron overload can lead to various pathological conditions,iron homeostasis is tightly regulated,and understanding this complex process will help pave the way to developing new therapeutic strategies for inflammatory disease.In recent years,significant progress has been made with respect to elucidating the roles of iron and iron-related genes in the development and maintenance of the immune system.Here,we review the timing and mechanisms by which systemic and cellular iron metabolism are regulated during the inflammatory response and during infectious disease,processes in which both the host and the pathogen compete for iron.We also discuss the evidence and implications that immune cells such as macrophages,T cells,and B cells require sufficient amounts of iron for their proliferation and for mediating their effector functions,in which iron serves as a co-factor in toll-like receptor 4(TLR4)signaling,mitochondrial respiration,posttranslational regulation,and epigenetic modification.In addition,we discuss the therapeutic implications of targeting ferroptosis,iron homeostasis and/or iron metabolism with respect to conferring protection against pathogen infection,controlling inflammation,and improving the efficacy of immunotherapy.