Bridging the Gap: Plant-Endophyte Interactions as a Roadmap to Understanding Small-Molecule Communication in Marine Microbiomes

Probing the composition of the microbiome and its association with health and disease states is more accessible than ever due to the rise of affordable sequencing technology. Despite advances in our ability to identify members of symbiont communities, untangling the chemical signaling that they use to communicate with host organisms remains challenging. In order to gain a greater mechanistic understanding of how the microbiome impacts health, and how chemical ecology can be leveraged to advance small-molecule drug discovery from microorganisms, the principals governing communication between host and symbiont must be elucidated. Herein, we review common modes of interkingdom small-molecule communication in terrestrial and marine environments, describe the differences between these environments, and detail the advantages and disadvantages for studies focused on the marine environment. Finally, we propose the use of plant-endophyte interactions as a stepping stone to a greater understanding of similar interactions in marine invertebrates, and ultimately in humans.     

Effect of height on the corrosion of steel and galvanized steel in nontropical coastal marine environments

In this study, the behavior of carbon steel and galvanized steel in nontropical coastal marine environments was evaluated. Evaluation was carried out with specimens with dimensions of 10 cm × 10 cm × 0.3 cm. These specimens were exposed to four testing stations (Iquique, Mejillones, Los Vilos, and San Vicente), where racks were installed both at ground level (ground), as well as in the upper zone of electrical transmission towers (tower). In each station, 24 specimens of A36 carbon steel and galvanized steel were placed (12 each). The corrosivity of the environment was measured using the ISO 9223, 9225, and 9226 standards. The specimens were evaluated on-site, monthly, through visual inspection and photographic record. Once withdrawn, the corrosion rate was determined and the corrosion products were analyzed through Raman and Fourier-transform infrared. The results show that, in all cases, the corrosion rate is greater in the tower than on the ground. However, even though the Los Vilos station is located farther from the sea (3,500 vs. ≈500 m), the corrosion rate of steel in the tower is the highest. This is caused by the generation of HCl from the transformation of lepidocrocite into goethite, in the presence of low chloride content, which acidifies the steel/corrosion product interface. In the case of galvanized steel, the corrosion rate is a function of the chloride content in the atmosphere, obtaining an excellent correlation between both parameters.     

船舶柴油机在用润滑油的现场监测

针对船舶柴油机在用润滑油的现场监测问题,研究确定了监测参数为水分、黏度、红外特征、元素浓度和铁磁性磨粒总量,并选择了相应的测量仪器。爆裂法水分现场快速检测仪可有效、快速判别含水量大于0.2%的油样;基于Hele-Shaw原理的黏度快速检测仪重复性误差小于3%,具有工程实用价值;安捷伦傅里叶红外光谱仪可用于监测在用油的红外特征变化;可采用基于电磁感应原理的铁量仪测量油样中的铁磁性磨粒总量;转盘电极原子发射光谱仪可测量油样中尺寸小于10μm的金属颗粒的元素浓度。铁量仪和发射光谱仪结合可有效监测异常磨损。指出船舶柴油机油样现场监测急须解决的问题是:缺少非铁磁性磨粒总量的快速、有效、可信的检测方法。     

某船用柴油机排气管路流-固耦合计算与保温效果研究

对某船用柴油机排气管路的流动与传热过程开展流-固耦合仿真分析。结果表明:受排气管路结构影响，管内流动方向和流速发生变化，局部区域产生明显的回流现象；排气管路外表面温度分布差异较大，平均温度高达534 ℃。为达到柴油机安全设计要求，在排气管路外壁敷设保温材料。分析结果表明:气凝胶纳米材料的保温效果优于硅酸铝纤维材料，在相同的运行条件和使用要求下，气凝胶纳米材料的敷设厚度更薄。     

基于EGR技术的船用低速二冲程柴油机增压系统匹配研究

针对采用EGR技术的船用低速二冲程柴油机在满足IMO排放法规时增压系统须兼顾多模式、宽流量范围运行的问题,基于某型低速二冲程柴油机在GT-Power软件中搭建整机及EGR系统仿真模型并校核。在此基础上研究涡轮增压器匹配、进排气旁通、废气旁通(EGB)等措施对该型柴油机TierⅢ和TierⅡ模式时性能的影响并得出系统匹配策略。研究结果表明:TierⅢ模式时,减小涡轮等效流通面积可有效恢复增压压力,但导致运行点接近压气机喘振线;引入进排气旁通则可有效解决喘振问题。TierⅡ模式时,采用EGR和EGB措施均可有效解决因涡轮等效面积减小带来的增压压力过高问题,但其中EGR方案NO_x排放较低,燃油消耗率偏高,而EGB方案燃油消耗率较低,NO_x排放偏高;综合应用EGR和EGB,即高负荷采用EGR,中低负荷采用EGB的匹配方案,可达到整机NO_x排放满足TierⅡ法规要求且燃油消耗率最低的设计目标。     

船用燃料油标准变化背景下的挑战与机遇

随着全球环境污染的不断加剧，国内外对船用燃料油的硫含量做了严格的限制。介绍了国内外船用 燃料油标准中硫含量的变化，国际海事组织（IMO）决定自2020年开始在全球范围内将燃料油硫质量分数控制在 0.5%以下，该标准将会对燃料油市场产生重要影响，用于调合低硫燃料油的中间馏分需求将会大幅增加，燃料油的价格也会随之大幅上涨，对于深加工能力强的炼厂是个机遇，同时替代燃料液化天然气（LNG）的发展也将迎来新机遇。     

Superhydrophobic aluminum alloy surface with excellent universality,corrosion resistance,and antifouling performance prepared without prepolishing

It is urgently necessary to seek more simple and effective methods to construct superhydrophobic metal surfaces to improve the corrosion resistance and antifouling performance. Herein, a facile method for fabricating superhydrophobic aluminum alloy surface is developed via boiling water treatment and stearic acid modification. It is noteworthy that no prepolishing on aluminum alloy is required and no caustic reagents and typical equipments are used during the preparation procedure. Therefore, the fabrication method is quite a simple and environment-friendly technique. Both micro- and nano-scaled binary structure forms at the resultant aluminum alloy surface while long alkyl chains are grafted onto the rough aluminum alloy surface chemically. Consequently, the resultant aluminum alloy exhibits outstanding superhydrophobicity. More importantly, the superhydrophobicity has excellent universality, diversity, stability, excellent corrosion resistance, and antifouling performance. The facile preparation, excellent superhydrophobic durability, and outstanding performance are quite in favor of the practical application.     

Marine Phospholipids from Fishery By-Products Attenuate Atherosclerosis

In this study, the anti-atherosclerotic properties of three marine phospholipids (MPLs) extracts from fishery by-products including codfish roe, squid gonad, and shrimp head are verified. Their effects on key factors involved in atherosclerosis are examined and compared to explore whether the differences in their constitutions lead to the differences in the function. All three MPLs dampen oxidation of low- density lipoproteins (LDL) in vitro. Treating RAW264.7 macrophages and HUVECs endothelial cells with each MPLs ranging 10–100 µg mL⁻¹ does not decrease cell viability, yet ox-LDL caused cytotoxicity of both cells are alleviated by 50 or 100 µg mL⁻¹ MPLs treatment. In addition, the three MPLs reduce ox-LDL induced macrophage foam-like transition, mainly through inhibition of lipid uptake. Of the three MPLs, the one from squid gonad exhibits the best effect. On the other hand, all three MPLs modulate inflammatory responses, equally, by inhibiting the adhesion of monocytes to endothelial cells, and decreasing secretion of pro-inflammatory cytokines IL-6 and MCP-1. Using a high-cholesterol diet induced zebrafish model, it is found that all three MPLs, especially the one from squid gonad, alleviates cholesterol accumulation in early plaques, and decreases total cholesterol as well as lipid peroxide in vivo. Practical Applications: As a way of making the best of the increasingly scarce marine resources, valuable lipid components can be recovered from by-products and wastes from the fishery industry. Here, we tested the anti-atherosclerotic effects and the mechanisms of three MPLs extracted from codfish roe, squid gonad, and shrimp head. Our study provides further evidence that marine phospholipids extracted from fishery by-products could protect against atherosclerosis, and helps to elucidate the structure-function relationship of MPLs.