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111.
The health benefits of fish oil, and its omega-3 long chain polyunsaturated fatty acid content, have attracted much scientific attention in the last four decades. Fish oils that contain higher amounts of eicosapentaenoic acid (EPA; 20:5n-3) than docosahexaenoic acid (DHA; 22:6n-3), in a distinctive ratio of 18/12, are typically the most abundantly available and are commonly studied. Although the two fatty acids have traditionally been considered together, as though they were one entity, different physiological effects of EPA and DHA have recently been reported. New oils containing a higher quantity of DHA compared with EPA, such as fractionated and concentrated fish oil, tuna oil, calamari oil and microalgae oil, are increasingly becoming available on the market, and other oils, including those extracted from genetically modified oilseed crops, soon to come. This systematic review focuses on the effects of high DHA fish oils on various human health conditions, such as the heart and cardiovascular system, the brain and visual function, inflammation and immune function and growth/Body Mass Index. Although inconclusive results were reported in several instances, and inconsistent outcomes observed in others, current data provides substantiated evidence in support of DHA being a beneficial bioactive compound for heart, cardiovascular and brain function, with different, and at times complementary, effects compared with EPA. DHA has also been reported to be effective in slowing the rate of cognitive decline, while its possible effects on depression disorders are still unclear. Interestingly, gender- and age- specific divergent roles for DHA have also been reported. This review provides a comprehensive collection of evidence and a critical summary of the documented physiological effects of high DHA fish oils for human health.  相似文献   
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ABSTRACT

While raw seed sprouts can threaten consumers’ health by foodborne pathogens, thermal or chemical disinfection of sprouts may cause some negative effects; instead, ozone can be a good alternative treatment. This study investigated the effect of nine ozone treatments (2000, 4000, and 6000 ppm within 1, 2, and 4 h) on wheat germ chemical compositions and microbial flora. The results indicated that ozonation with 2000 ppm during 4 h was the optimized treatment with the greatest effect on decreasing the microbial load while it had the minimum effect on antioxidant properties, lipid oxidation, and moisture content of raw wheat germ.  相似文献   
114.
Metallic bipolar plates can significantly increase the power density of polymer electrolyte membrane fuel cells; however, they require corrosion-protection coatings with desirable physical and chemical properties. In this study, diamond-like carbon (DLC) film coatings are investigated as such coatings potentially for metallic-based bipolar plates, with the focus on the relation between the processes and properties of the coatings under different coating deposition conditions of Plasma Enhanced Chemical Vapor Depsoition (PECVD) method. Various characterization techniques are applied to study the adhesion, structure, morphology, wettability, corrosion, and electrical resistivity of the film coatings. XPS, EDAX, and SEM analyses are used to identify the ratio of sp3 (diamond-like) and sp2 (graphite-like) bonds in the coatings, surface elements, and surface morphology, respectively. Potentiodynamic polarization test is utilized to investigate the corrosion behaviors of substrates with and without DLC coatings. Further, the electrical resistivity of the DLC films is measured by the four-point probe method. The results indicate that higher deposition power along with the absence of argon gas results in more sp3 than sp2 bonds in the coating, and the electrical resistivity is increased accordingly. The coating films deposited from methane (CH4) exhibit superior adhesion to the stainless steel (SS316) substrates over those generated from acetylene (C2H2) gas. Coating films deposited on the metallic substrates change the surface wettability appreciably. Further, polarization tests show that coatings generated with a low power of 250 W and higher argon gas percentage of 30% provide better anti-corrosion protection for metallic-based bipolar plates.  相似文献   
115.
A novel nano-structures mercury(II) coordination compound, [Hg (HPCIH) I2] (1), (“HPCIH” is the abbreviation of 2-pyridinecarbaldehyde isonicotinoyl hydrazone) has been synthesized by a hydrothermal method that produces the coordination compound at nano size. The new nanostructure was characterized by transmission electron microscopy, scanning electron microscopy, X-ray powder diffraction elemental analysis and IR spectroscopy. Compound 1 was structurally characterized by single crystal X-ray diffraction and the single-crystal structure of this complex shows that each mercury(II) center is five coordinated with two N-donor and one O-donor atoms from “HPCIH” ligand and two iodo anions. Self-assembly of this complexes is realized by CH····I, I····I and π–π stacking interactions. The supramolecular features in these complexes are controlled by weak directional intermolecular interactions.  相似文献   
116.
Cellulose-graft-polyacrylamide/hydroxyapatite composite hydrogels of different weight ratios were prepared through a suspension polymerization method. Physical and chemical characteristics of the composite were investigated by Fourier transform infrared spectroscopy and scanning electron microscopy. The swelling behaviors of the composite hydrogels were investigated under varying conditions of time, temperature and pH. The optimized swelling capacity in standard conditions was found to be 5197% per gram of the hydrogel. The prepared hydrogel has the potential to be used for ion adsorption in water treatment. Such a possibility was examined through adsorption of copper (II) ions from an aqueous solution. The effects on adsorption of varying the time, pH, and initial concentration of copper (II) solution as well as some thermodynamic parameters were also investigated. The maximum adsorption capacity was found to be 175 mg per gram of composite hydrogel in dried state. The mechanism of adsorption was well presented using a pseudo-second-order kinetic model. Finally, the mercury-loaded hydrogel was regenerated without losing its original activity and stability.  相似文献   
117.
The harmful effect of nickel ions released from conventional stainless steel implants has provided a high level of motivation for the further development of nickel-free stainless steels. In this paper, the microstructure of medical-grade nickel-free stainless steel powders, with the chemical composition of ASTM F2581, is studied during mechanical alloying and subsequent annealing. Rietveld X-ray diffraction and transmission electron microscopy evaluations reflect nanocrystallization, austenitization and amorphization of the powders due to mechanical activation. It is also realized that annealing of the as-milled powder can develop a single austenitic structure with nanometric crystallite sizes, implying a considerable inherent resistance to grain growth. This study demonstrates the merit of mechanical alloying and subsequent annealing in the development of nanostructured medical-grade stainless steels.  相似文献   
118.
Oxidative stability of the purified common Kilka triacylglycerols (PKO) as affected by 1–8% w/w of bene kernel (BKO) and hull (BHO) oils was studied and compared with that of 100 mg kg?1 of BHT and α‐tocopherol. Lipid oxidation was measured by monitoring peroxide value till the minute 80 (PV80, meq kg?1) and also by determining the oxidative stability index at 60 °C (OSI60, h). In the Rancimat test, the OSI60 of the PKO (1.66 h) was significantly increased by some of the added antioxidants, and the BKO 8% (7.98 h) had the highest antioxidant activity with no significant differences among the BHT, α‐tocopherol and the BHO 8%. Furthermore, an exponential regression curve with a good coefficient of determination (R2 > 0.94) was observed between the changes in the PV80 and OSI60 values of the PKO.  相似文献   
119.
Clean Technologies and Environmental Policy - Natural gas combined-cycle (NGCC) turbines with carbon capture and storage (CCS) could be an important source of low-carbon electricity in the future....  相似文献   
120.
Retinal image analysis is a challenging problem due to the precise quantification required and the huge numbers of images produced in screening programs. This paper describes a series of innovative brain-inspired algorithms for automated retinal image analysis, recently developed for the RetinaCheck project, a large-scale screening program for diabetic retinopathy and other retinal diseases in Northeast China. The paper discusses the theory of orientation scores, inspired by cortical multi-orientation pinwheel structures, and presents applications for automated quality assessment, optic nerve head detection, crossing-preserving enhancement and segmentation of retinal vasculature, arterio-venous ratio, fractal dimension, and vessel tortuosity and bifurcations. Many of these algorithms outperform state-of-the-art techniques. The methods are currently validated in collaborating hospitals, with a rich accompanying base of metadata, to phenotype and validate the quantitative algorithms for optimal classification power.  相似文献   
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