The Effect of Sericin from Various Extraction Methods on Cell Viability and Collagen Production

Silk sericin (SS) can accelerate cell proliferation and attachment; however, SS can be extracted by various methods, which result in SS exhibiting different physical and biological properties. We found that SS produced from various extraction methods has different molecular weights, zeta potential, particle size and amino acid content. The MTT assay indicated that SS from all extraction methods had no toxicity to mouse fibroblast cells at concentrations up to 40 μg/mL after 24 h incubation, but SS obtained from some extraction methods can be toxic at higher concentrations. Heat-degraded SS was the least toxic to cells and activated the highest collagen production, while urea-extracted SS showed the lowest cell viability and collagen production. SS from urea extraction was severely harmful to cells at concentrations higher than 100 μg/mL. SS from all extraction methods could still promote collagen production in a concentration-dependent manner, even at high concentrations that are toxic to cells.     

The development of injectable gelatin/silk fibroin microspheres for the dual delivery of curcumin and piperine

The objective of this study was to develop the microspheres from gelatin (G) and silk fibroin (SF) aimed to be applied for the controlled release of curcumin and piperine. The glutaraldehyde-crosslinked G/SF microspheres at various weight blending ratios (100/0, 70/30, 50/50, and 30/70) were successfully fabricated by water in oil emulsion technique. The microspheres prepared from all compositions were in a round shape with homogeneous size distribution both in the dried (194–217 μm) and swollen states (297–367 μm). When subjected in collagenase solution at physiological condition, the G microspheres gradually degraded within 14 days while the blended G/SF microspheres, particularly at 50/50 and 30/70, were not degraded. For the release application, the microspheres were loaded with curcumin and/or piperine. It was found that the microspheres composed of SF tended to entrap curcumin and piperine with the high entrapment and loading efficiencies, possibly due to their hydrophobic interactions. The G/SF microspheres, particularly at the ratios of 50/50 and 30/70, released curcumin and piperine in a sustained manner both for the single and dual release systems. The controlled dual release of curcumin and piperine from the G/SF microspheres would prolong their half-life, provide the optimal concentrations for therapeutic effects at a target site, and improve the bioavailability of curcumin. These novel injectable microspheres dually releasing curcumin and piperine would be introduced for the treatment of diseases without the need of operation.     

Changing in processing yield and physical properties of frozen white shrimp (Penaeus vannamei) treated with lysine and sodium bicarbonate

The objective of this research was to investigate the phosphate alternative use of natural compound, lysine with sodium bicarbonate (NaHCO₃), at low concentration for freezing of white shrimp (Penaeus vannamei). Shrimp were treated with lysine, NaHCO₃ and lysine with NaHCO₃ at various concentrations and frozen in an air‐blast freezer. Thawing yield, cooking yield, colour, texture and nanostructure of the sample were studied compared to the control (nontreated sample) and sodium tri‐polyphosphate (STPP) treated one. Use of lysine/NaHCO₃ each at 1% (w/v) could improve water holding capacity (WHC) of the frozen shrimp, increasing cooking yield to 100.45% (w/w), comparable to the 101.73% (w/w) of STPP‐treated sample. The colour of the noncook‐thawed shrimp was also improved. Microstructure and lipid oxidation of the treated samples were also studied. The combination of lysine and NaHCO₃ indicated high potential use as phosphate alternative for frozen white shrimps.     

Potential of Selected Tropical Fruit Peels as Dietary Fiber in Functional Foods

The peels of rambutan, durian, santol, longan, longong, Kaeo mango, and Chok Anan mango were evaluated for their potential to be used as dietary fiber for food enrichment. All dietary fiber samples prepared from selected fruit peels showed high content of total dietary fiber (52–84 g/100 g dry matter) and also exhibited the significant difference in dietary fiber quality. All dietary fiber samples were safe for consumption, which was ensured by the results of an acute toxicity test. In summary, peels of tropical fruits used in this study had a great potential to be used as low-caloric functional ingredients for dietary fiber enrichment.     

Effect of Raw Material Preparation on Rice Vermicelli Quality

The physicochemical properties of high amylose rice flour prepared from wet milling and dry milling were examined and the rice vermicelli quality made from these flour samples was evaluated. The effect of flour particle size on rice vermicelli quality was also determined. The milling method affected chemical compositions and all physicochemical properties of the flour. A higher degree of starch damage occurred in drymilled flour. Rice vermicelli made from dry‐milled flour had higher cooking losses and softer texture than that made from wet‐milled flour and the commercial reference products. Flour particle size influenced both cooking and textural quality of rice vermicelli but did not influence the water absorption index. Flours with larger particle sizes gave vermicelli with higher cooking loss and less desirable texture than flours with smaller particle sizes. Flour with particle sizes less than 200 mesh produced acceptable vermicelli in terms of cooking and textural quality.     

Adapting to Less Water: Household Willingness to Pay for Decentralised Water Systems in Urban Australia

In South East Queensland (SEQ), extended periods of drought and unprecedented population growth have resulted in a water strategy reliant on permanent water conservation measures. As a result, there has been increasing emphasis on the installation of decentralised water systems at the household level, in particular, rainwater tanks and greywater systems to ease the water shortage stress. Results from a survey of 590 households in SEQ reveal that willingness to pay (WTP) for rainwater tanks and greywater systems range from $800 to $7,400 and from $1,700 to $14,100, respectively. When compared to the actual market price, WTP is substantially lower and subsidies will be required to encourage adoption. Nonetheless, a subsidy of $500 can lead to 100 % uptake of greywater diversion devices. Hence, the policy implication is that not all devices are preferred and subsidising greywater diversion devices would lead to the highest level of uptake with the least amount of subsidy spending.     

Numerical Study of Flicker Noise in p-Type $ hbox{Si}_{0.7}hbox{Ge}_{0.3}/hbox{Si}$ Heterostructure MOSFETs

Device-level simulation capabilities have been developed to investigate low-frequency noise behavior in p-type Si_0.7Ge_0.3/Si heterostructure MOS (SiGe p-HMOS) transistors. The numerical model is based on the impedance field method; it accounts for a trap-induced carrier number fluctuation, a layer-dependent correlated mobility fluctuation, and a Hooge mobility fluctuation in the buried and parasitic surface channels, respectively. Simulations based on such models have been conducted for SiGe p-HMOS transistors, and the results have been carefully correlated with experimental data. Quantitative agreement has been obtained in terms of the noise level dependence on gate biases, drain currents, and body biases, revealing the important role of the dual channels in the low-frequency noise behavior of SiGe p-HMOS devices.     

Beads fabricated from alginate,hyaluronic acid,and gelatin using ionic crosslinking and layer-by-layer coating techniques for controlled release of gentamicin

The alginate/hyaluronic acid (AL/HA) blended beads at different ratios (AL70HA30, AL50HA50, and AL30HA70) were formed by ionic crosslinking technique. The layer-by-layer coating of the beads with two opposite charged molecules, positive-charged type A gelatin (GA), and negative-charged AL, using alternate soaking technique was introduced to stabilize the beads. The AL70HA30, AL50HA50 beads showed high stability because of high ionic crosslinked AL component. Two-layer coating resulted in an appropriate layer that maximized the stability of the AL/HA beads. The higher ratio of HA resulted in the higher water absorption ability but degradation rate was accelerated. An antibiotic gentamicin was loaded into the beads with the entrapment efficiency of 69–89%. The beads containing 30% and 50% HA and coated with two layers showed a sustained release of gentamicin while the release behavior was governed by the diffusion and degradation of the beads. The gentamicin released from all beads also potentially inhibited the growth of Staphylococcus aureus (gram-positive) and Escherichia coli (gram-negative) bacteria up to at least 48 h. These beads with antibacterial activity can be further explored for the application as bone void filling material for treatment of infection in bone diseases such as osteoarthritis or rheumatoid. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 46893.     

The influence of coping appraisals on the adoption of decentralised water systems in Australia

In Australia, water scarcity has resulted in the need for re-evaluating demand management policies, as well as the identification of alternative water supplies. Specifically, water utilities have been focusing on increasing the adoption of household level decentralised water systems (DWS). While such engineering solutions may be effective, understanding the factors which influence adoption is crucial for widespread uptake. Protection Motivation (PM) theory was used to assess DWS adoption in a sample of 295 homeowners across South East Queensland, Australia. Results provided good support for the application of PM theory to understanding whether people cope adaptively to water shortage threats. The model’s hypothesised link between adaptive coping and behavioural intention was also supported, suggesting PM theory can be used to understand people’s intention to adopt DWS in the context of the drought. The predictive ability of the PM model improved significantly when demographic variables – age and perceived water – use were included.