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This paper aims to evaluate effects of the fortification of polyphenolic compound mixtures of quercetin, caffeic acid, tryrosol and hydroxytyrosol in olive oil oxidation.

The authors measured olive oxidation initiated by copper using thiobarbituric acid reactive substance, as an indicator of lipid peroxidation.

Overall, most mixture combinations exhibited oxidation similar to olive oil alone. Some mixture combinations of polyphenolic compounds acted as antioxidants; however, as the concentrations were changed, they became prooxidant in nature.

In vitro studies have limitations for extrapolation to in vivo and clinical studies.

Such information will be useful in determining optimal concentrations and combinations of antioxidants for reducing rancidity and perhaps as models that could be used to modulate various chronic diseases that are associated with oxidative stress.

Olive oil, along with fruits, vegetables and fish, are important constituents of health promoting diets, such as the Mediterranean diet. Active ingredients include monounsaturated fatty acids, oleic acid and a variety of antioxidants including various polyphenolic compounds.

The purpose of this study was to characterise the physiochemical properties of selected exotic seasonal tropical fruits available in Singapore.

A total of 11 seasonal tropical fruits including cempedak, chiku, custard apple, jackfruit, longkong, mangosteen, red jambu, pearl jambu, rambutan, salak and starfruit were analyzed for their sugars, organic acids and free phenolic acids composition using liquid chromatographic methods. Total phenolic content (free and bound), total soluble solids and pH were determined using Folin‐Ciocalteu method, refractometer and pH meter, respectively.

Fructose, glucose and sucrose were the main sugars in all the fruits. Cempedak had the highest sucrose concentration, while custard apple had the highest content of fructose and glucose. Malic and citric acids were the major organic acids in most of the fruits, except for pearl jambu and red jambu where succinic acid was the dominant acid. The total phenolic content varied from 122.94 to 712.20 mg gallic acid equivalent (GAE)/kg fresh weight (FW). Ferulic (0.631 mg/kg) and sinapic acids (1.506 mg/kg) were the predominant free phenolic acids in custard apple, while caffeic acid was the main free phenolic acid in jackfruit, salak and starfruit.

The paper demonstrates that the physiochemical characteristics of the 11 tropical fruits varied markedly, which is responsible for the differential flavour and stability. The findings are useful for epidemiological research and predicting the degree of ripeness, stability and post‐harvest processing required for these fruits.

This paper aims to evaluate the association between the α‐tocopherol with the levels of serum anti‐oxLDL autoantibodies and the risk markers for cardiovascular disease.

A normolipidemic control group (n=30) and a hypercholesterolemic group (n=33) were used. Plasma lipid profile (colorimetric method), anti‐oxLDL autoantibodies (ELISA) and α‐tocopherol (HPLC) were analysed.

The α‐tocopherol (β=−0.714; p=0.001) is negatively associated with anti‐oxLDL autoantibodies in serum and with other risk markers for cardiovascular disease (BMI, WC, total cholesterol, LDL‐c) and positively associated with HDL‐c.

Oxidized low density lipoprotein (oxLDL) and their autoantibodies are increased in subjects with hypercholesterolemia. The α‐tocopherol can influence the levels of serum anti‐oxLDL autoantibodies.

In June 1973 the main provisions of the Act of Parliament governing the handling and storage of highly flammable liquids and liquefied petroleum gas in factories comes into operation.

Presents development and characterisation of a new metal/polymer composite material for use in fused deposition modelling (FDM) rapid prototyping process with the aim of application to direct rapid tooling. The work represents a major development in reducing the cost and time in rapid tooling.

The material consists of iron particles in a nylon type matrix. The detailed formulation and characterisation of the thermal properties of the various combinations of the new composites are investigated experimentally. Results are compared with other metal/polymer composites used in rapid tooling.

The feedstock filaments of this composite have been produced and used successfully in the unmodified FDM system for direct rapid tooling of injection moulding inserts. Thermal properties are found to be acceptable for rapid tooling applications for injection moulding.

Introduces an entirely new metal based composite material for direct rapid tooling application using FDM RP system with desired thermal properties and characteristics. This will reduce the cost and time of manufacturing tooling inserts and dies for injection moulding.

The poor corrosion resistance of the ferrite-pearlite steel limits its application in marine engineering because of the enhanced galvanic effect caused by continuously accumulated cementite. Cr as one principal alloying element is commonly used to improve the corrosion resistance of steels. This paper aims to study the effect of Cr on corrosion behaviors of ferrite-pearlite steels in an acidic environment.

The tested steels were immersed in a simulated solution of 10 Wt.% NaCl with pH 0.85 for 72 h to evaluate the corrosion rate. After the immersion test, the corrosion morphologies and products were tested by scanning electron microscopy, energy dispersive X-ray analysis and X-ray diffraction. Meanwhile, an electrochemical workstation was used to study the electrochemical behaviors of samples.

At the initial corrosion stage, the corrosion rate increased in the sequence of Cr₀, Cr_0.5 and Cr₁ steels, which was because of the competitive effect between the area ratio and the driving force caused by alloyed Cr. However, Cr₁ steel exhibited the best corrosion resistance after a 72-h immersion test. This was because the alloyed Cr promoted the formation of protective Fe₂O₃ and FeCr₂O₄, which suppressed the preferential dissolution of ferrite and, thus, reduced the accumulation rate of carbides, resulting in the weakened galvanic corrosion.

This paper reports the role that Cr plays in the galvanic corrosion of ferrite-pearlite steels, which is important for the engineering application of ferrite-pearlite steels in marine environment.

Polymeric parts produced by 3D stereolithography (SL) process have poorer mechanical properties as compared to their counterparts fabricated via conventional methods, such as injection or compression molding. Adding nanofillers in the photopolymer resin for SL could help improve mechanical properties. This study aims to achieve enhancement in mechanical properties of parts fabricated by SL, for functional applications, by using well-dispersed nanofillers in the photopolymers, together with suitable post-processing.

Carbon nanotubes (CNTs) have high strength and Young’s modulus, making them attractive nanofillers. However, dispersion of CNTs in photopolymer is a critical challenge, as they tend to agglomerate easily. Achieving good dispersion is crucial to improve the mechanical properties; thus, suitable dispersion mechanisms and processes are examined. Solvent exchange process was found to improve the dispersion of multiwalled carbon nanotubes in the photopolymer. The UV-absorbing nature of CNTs was also discovered to affect the curing properties. With suitable post processing, coupled with thermal curing, the mechanical properties of SL parts made from CNTs-filled resin improved significantly.

With the addition of 0.25 wt.% CNTs into the photopolymer, tensile stress and elongation of the 3D printed parts increased by 70 and 46 per cent, respectively. With the significant improvement, the achieved tensile strength is comparable to parts manufactured by conventional methods.

This allows functional parts to be manufactured using SL.

In this paper, an improved procedure to incorporate CNTs into the photopolymer was developed. Furthermore, because of strong UV-absorption nature of CNTs, curing properties of photopolymer and SL parts with and without CNT fillers were studied. Optimized curing parameters were determined and additional post-processing step for thermal curing was discovered as an essential step in order to further enhance the mechanical properties of SL composite parts.

This paper aims to examine the effects of substituting durum wheat semolina (DWS) with high-quality cassava starch (HQCS) in macaroni noodle production.

The effect of substituting semolina with cassava starch in macaroni production at six levels, namely, 0, 20, 30, 50, 70, 100 per cent, and variation in hydration levels of 45, 50 and 55 per cent and their interaction were studied.

As substitution of DWS with HQCS increased from 0 to 50 per cent at 45 per cent hydration, amylose content increased from 15.91 to 22.79 per cent. However, beyond 50 per cent substitution level, the amylose content dropped significantly to 20.10 per cent. Yet, this reduction did not affect the extrusion ability of the doughs. Analysis of variance revealed that changes observed in the dough properties were not significant (p > 0.05).

Trial productions of cassava macaroni noodles under factory processing conditions need to be explored. Also, cooking trials and consumer acceptability studies need to be conducted to pave the way for adoption by manufacturers.

Dried noodle products enjoy widespread popularity because of their shelf life, lower glycaemic indices, simplicity of preparation and moderate costs. This study showed the potential of substituting DWS with HQCS with no adverse effect on the dough and macaroni noodle characteristics.

The adoption of the process described in this study would result in increased utilization of cassava, broaden existing food base and provide household food security for both rural and urban population.

This paper has shown the suitability of substituting DWS obtained from imported durum wheat, with HQCS: indigenous to Africa, for the economic benefit of macaroni manufacturers.