Ozonation of a mixture of dialkylphthalates in aqueous solution

Ozonation of dimethyl phthalate, diethyl phthalate and dipropyl phthalate was carried out to evaluate the potential of ozonation for phthalate removal from water. Phthalates with longer alkyl chains, which are often more resistant to biodegradation were found to be more degradable than those with shorter alkyl chains. The degradation of phthalates by ozonation follows the pseudo‐first‐order kinetic model. The rate of phthalates degradation increased exponentially with increasing temperature in the range studied (20 to 50 °C) and in proportion with applied ozone dosages. The rate of phthalates degradation was found to increase with increasing pH of the solution from 2.6 to 11.0, and decreased exponentially with increasing initial concentrations of the phthalates. Degradation of phthalates via ozonation was found to develop dominantly through direct reaction with hydroxyl radicals. Copyright © 2010 Society of Chemical Industry     

Molecular Mechanisms of Antiproliferative and Apoptosis Activity by 1,5-Bis(4-Hydroxy-3-Methoxyphenyl)1,4-Pentadiene-3-one (MS13) on Human Non-Small Cell Lung Cancer Cells

Diarylpentanoid (DAP), an analog that was structurally modified from a naturally occurring curcumin, has shown to enhance anticancer efficacy compared to its parent compound in various cancers. This study aims to determine the cytotoxicity, antiproliferative, and apoptotic activity of diarylpentanoid MS13 on two subtypes of non-small cell lung cancer (NSCLC) cells: squamous cell carcinoma (NCI-H520) and adenocarcinoma (NCI-H23). Gene expression analysis was performed using Nanostring PanCancer Pathways Panel to determine significant signaling pathways and targeted genes in these treated cells. Cytotoxicity screening revealed that MS13 exhibited greater inhibitory effect in NCI-H520 and NCI-H23 cells compared to curcumin. MS13 induced anti-proliferative activity in both cells in a dose- and time-dependent manner. Morphological analysis revealed that a significant number of MS13-treated cells exhibited apoptosis. A significant increase in caspase-3 activity and decrease in Bcl-2 protein concentration was noted in both MS13-treated cells in a time- and dose-dependent manner. A total of 77 and 47 differential expressed genes (DEGs) were regulated in MS13 treated-NCI-H520 and NCI-H23 cells, respectively. Among the DEGs, 22 were mutually expressed in both NCI-H520 and NCI-H23 cells in response to MS13 treatment. The top DEGs modulated by MS13 in NCI-H520—DUSP4, CDKN1A, GADD45G, NGFR, and EPHA2—and NCI-H23 cells—HGF, MET, COL5A2, MCM7, and GNG4—were highly associated with PI3K, cell cycle-apoptosis, and MAPK signaling pathways. In conclusion, MS13 may induce antiproliferation and apoptosis activity in squamous cell carcinoma and adenocarcinoma of NSCLC cells by modulating DEGs associated with PI3K-AKT, cell cycle-apoptosis, and MAPK pathways. Therefore, our present findings could provide an insight into the anticancer activity of MS13 and merits further investigation as a potential anticancer agent for NSCLC cancer therapy.     

Characterization of the components present in the active fractions of health gingers (Curcuma xanthorrhiza and Zingiber zerumbet) by HPLC–DAD–ESIMS

Curcuma xanthorrhiza and Zingiber zerumbet are two of the most commonly used ingredients in Indo-Malaysian traditional medicines, health supplements and tonics. Recently, a number of products derived from the aqueous extracts of these species have appeared in the market in the form of spray-dried powder packed in sachet or bottle. On-line high performance liquid chromatography, coupled with diode array detection and electrospray ion trap tandem mass spectroscopy (HPLC–DAD–ESI–MSⁿ), was used to analyze the components in the antioxidant-active fractions from the rhizomes of these species. Three components were identified from C. xanthorrhiza, including bisdemethoxycurcumin (1), demethoxycurcumin (2) and curcumin (3). The active fraction from Z. zerumbet consisted of five components, including kaempferol 3-O-rhamnoside (4), compound 5 [kaempferol 3-O-(2″-O-acetyl)rhamnoside (5a) or kaempferol 3-O-(3″-O-acetyl)rhamnoside (5b)], kaempferol 3-O-(4″-O-acetyl)rhamnoside (6), kaempferol 3-O-(3″,4″-O-diacetyl)rhamnoside (7) and kaempferol 3-O-(2″,4″-O-diacetyl)rhamnoside (8). To confirm their identities, the components from Z. zerumbet were isolated conventionally and were analyzed by spectroscopic techniques as well as by comparison with literature data.     

Vibration‐based piezoelectric,electromagnetic, and hybrid energy harvesters for microsystems applications: A contributed review

Wireless sensor nodes (WSNs) and embedded microsystems have recently gained tremendous traction from researchers due to their vast sensing and monitoring applications in various fields including healthcare, academic, finance, environment, military, agriculture, retail, and consumer electronics. An essential requirement for the sustainable operation of WSN is the presence of an uninterrupted power supply; which is currently obtained from electrochemical batteries that suffer from limited life cycles and are associated with serious environmental hazards. An alternative to replacing batteries of WSNs; either the direct replacement or to facilitate battery regular recharging, is by looking into energy harvesting for its sustainable drive. Energy harvesting is a technique by which ambient energy can be converted into useful electricity, particularly for low‐power WSNs and consumer electronics. In particular, vibration‐based energy harvesting has been a key focus area, due to the abundant availability of vibration‐based energy sources that can be easily harvested. In vibration‐based energy harvesters (VEHs), different optimization techniques and design considerations are taken in order to broaden the operation frequency range through multi‐resonant states, increase multi‐degree‐of‐freedom, provide nonlinear characteristics, and implement the hybrid conversion. This comprehensive review summarizes recent developments in VEHs with a focus on piezoelectric, electromagnetic, and hybrid piezoelectric‐electromagnetic energy harvesters. Various vibration and motion‐induced energy harvesting prototypes have been reviewed and discussed in detail with respect to device architecture, conversion mechanism, performance parameters, and implementation. Overall sizes of most of the reported piezoelectric energy harvesters are in the millimeter to centimeter scales, with resonant frequencies in the range of 2‐13 900 Hz. Maximum energy conversion for electromagnetic energy harvesters can potentially reach up to 778.01 μW/cm³. The power produced by the reported hybrid energy harvesters (HEHs) is in the range of 35.43‐4900 μW. Due to the combined piezoelectric‐electromagnetic energy conversion in HEHs, these systems are capable of producing the highest power densities.     

Geometric and radiometric evaluation of Razaksat medium-sized aperture camera data

Razaksat, a high-resolution Malaysian remote-sensing satellite, was launched on 14 July 2009. It carries a medium-sized aperture camera (MAC) with one panchromatic and four multispectral bands, of 2.5 and 5 m spatial resolution, respectively. The satellite was placed in a near-equatorial orbit with a low inclination angle of 9° to enable an optimum 14 overpasses per day over the equatorial region (i.e. 9° N to 9° S) as compared to only three daily passes over Malaysia for near-polar orbiting satellites. This article reports on evaluation of the panchromatic and multispectral images of MAC: (i) a geometric evaluation of the panchromatic and multispectral MAC images; (ii) a radiometric evaluation, focusing particularly on the noise level and sharpness of the MAC images; (iii) an evaluation of the MAC panchromatic data for updating planimetric topographic features; and (iv) a classification of MAC multispectral data for land-cover mapping. The noise level within the image set was found to increase with the intensity, while the sharpness of edges tested on the images in all non-homogeneous targets was relatively marginal. However, the outcome of the analysis showed the utility and potential of high-resolution panchromatic and multispectral bands of the Razaksat as stipulated in the system mission for terrain mapping.     

Preparation of Polymer Composite Membrane Reinforced by Natural Fibers (Fiber and Stem of Date Palm) for Treatment of Industrial Waste Water Residue

Theoretical Foundations of Chemical Engineering - The developed industries are utilized natural waste fibers as a clean criteria device. This work utilized natural composite membranes in the...     

Multi-Objective Optimization of Micro Pin-Fin Arrays for Cooling of High Heat Flux Electronics with a Hot Spot

ABSTRACT

This article presents fully three-dimensional conjugate heat transfer analysis and a multi-objective, constrained optimization to find sizes of pin-fins, inlet water pressure, and average speed for arrays of micro pin-fins used in the forced convection cooling of an integrated circuit with a uniformly heated 4 × 3 mm footprint and a centrally located 0.5 × 0.5 mm hot spot. Sizes of micro pin-fins having cross sections shaped as circles, symmetric airfoils, and symmetric convex lenses are optimized to completely remove heat due to a steady, uniform heat flux of 500 W cm^?2 imposed over the entire footprint (background heat flux) and a steady, uniform heat flux of 2000 W cm^?2 imposed on the hot spot area only (hot spot heat flux). The two simultaneous objectives are to minimize maximum substrate temperature and minimize pumping power, while keeping the maximum temperature constrained below 85°C and removing all of input thermal energy by convection. The design variables are the inlet average velocity and size of the pin-fins. A response surface is generated for each of the objectives and coupled with a genetic algorithm to arrive at a Pareto frontier of the best trade-off solutions. Numerical results show that, for a specified maximum temperature, optimized arrays with pin-fins having symmetric convex lens shapes create the lowest pressure drop, followed by the symmetric airfoil and circular cross-section pin-fins. An a posteriori three-dimensional stress–deformation analysis incorporating hydrodynamic and thermal loads shows that Von-Mises stress for each pin-fin array is significantly below the yield strength of silicon, thus, confirming structural integrity of such arrays of micro pin-fins.     

Evaluation of Metal Concentrations in Red Tilapia (Oreochromis spp) from Three Sampling Sites in Jelebu, Malaysia Using Principal Component Analysis

Concentration of V, Mn, Fe, Co, Cu, Zn, As, Se, Cd, and Pb in muscle, liver, and gill tissues of red tilapia (Oreochromis spp) sampled from three different aquaculture sites which include earthen pond, ex-tin mining pool, and concrete tank in Jelebu, Negeri Sembilan, were determined using microwave-assisted digestion–inductively coupled plasma-mass spectrometry. Accumulation patterns relating organs and elements, as well as origins and elements, were evaluated using multivariate statistics. With the aid of principal component analysis, it is possible to visualize the distribution pattern of metals in different organs as well as clustering tendencies of tilapia samples according to the production sites. In general, levels of V, Co, Fe, Cu, Zn, Se, and Cd in liver were higher than those in muscles and gills, whereas Mn and Pb were higher in gills while As in muscles. Results from principal component analysis revealed that there are similar pattern of metal distribution among organs regardless of the production sites. It is also suggested that Cu, As, and Pb are the best describers in characterizing the studied organs, where liver tissues are associated with high Cu, gills with high Pb, and muscles with high As. On the other hand, V, Co, and Pb are observed to be key discriminants for sample origins.     

Influence of Different Extraction Media on Phenolic Contents and Antioxidant Capacity of Defatted Dabai (<Emphasis Type="Italic">Canarium odontophyllum</Emphasis>) Fruit

Dabai (Canarium odontophyllum) is a potential “functional fruit”. Future commercialization of dabai fat as healthy oil may result in the accumulation of defatted dabai as a by-product. This study was carried out to determine the total phenolics and antioxidant capacity of defatted dabai parts as a new source of functional food and nutraceutical ingredient. In this study, defatted dabai parts were extracted using different extraction media (methanol, ethanol, ethyl acetate, acetone, and water) and analyzed for total phenolics, total flavonoids, total anthocyanins, and antioxidant capacity (ABTS⁺ radical scavenging and ferric-reducing antioxidant power assays) using spectrophotometric and high-performance liquid chromatography methods. Major phenolics in defatted dabai peel extracted using methanol were catechin and epigallocatechin while in water extract, major phenolic acid was ellagic acid. Defatted dabai peel also had higher anthocyanidin content than its pulp. The peel of a defatted dabai fruit extracted using methanol contained a high total phenolics and Trolox equivalent antioxidant capacity (TEAC). Ethyl acetate extract of defatted dabai parts had the least phenolics compared in ethanol and acetone extracts. Higher total phenolics and TEAC values were observed in water extract of a defatted dabai peel than ethanol, acetone, and ethyl acetate extracts. Hence, methanol extract of a defatted dabai peel could probably be used as a natural antioxidant.