Decreasing effect of fluoride content in Antarctic krill (Euphausia superba) by chemical treatments

Decreasing effects of fluoride contents in Antarctic krill (Euphausia superba) as affected by chemical treatments with and without heating were investigated. The used chemicals were NaOH, Na₂CO₃, Na₂SO₃, citric acid, acetic acid, phosphoric acid, HCl, ethanol, lysine, aminoguanidine, arginine, carnitine, betaine, and creatine. Fluoride contents per dry weight were 788 ± 10 mg kg^?1 in the whole body of krill (WBK) and 294 ± 4 mg kg^?1 in the peeled krill meat (PKM) respectively. When WBK was treated with chemicals with and without heating or thawed, fluoride was not decreased. On the other hand, when the PKM was treated with chemicals without heating was remarkably decreased to less than 100 mg kg^?1, which is the criteria recommended by FDA. Particularly, the treatment of betaine without heating showed the best reduction effect of 30 ± 6 mg kg^?1, followed by carnitine (38 ± 17 mg kg^?1), acetic acid (52 ± 1 mg kg^?1), phosphoric acid (67 ± 2 mg kg^?1) and hydrochloric acid (68 ± 1 mg kg^?1).     

Induction of the cell cycle arrest and apoptosis by flavonoids isolated from Korean Citrus aurantium L. in non-small-cell lung cancer cells

This study investigated the anti-proliferative and apoptotic effect of flavonoids isolated from Korean Citrus aurantium L. using A549 lung cancer cells. Flavonoids potently inhibited of A549 cells in a dose-dependent manner, whereas flavonoids had a weak inhibitory effect on proliferation of WI-38 cells. Flow cytometry and Western blot analysis showed that flavonoids induced cell cycle arrest at the G2/M checkpoint by controlling the proteins expression level of cyclin B1, cdc2, cdc25c and p21^WAF1/CIP1. Also, flavonoids induced apoptosis through the regulation of the expression of caspases, cleaved PARP and Bax/Bcl-xL ratio. The activity of caspase-3 on A549 cells increased in a dose-dependent manner. These results clearly indicated that the anti-cancer effect of flavonoids on A549 cells follows multiple cellular pathways through G2/M arrest and the induction of apoptosis.     

The new iridium complexes involving pyridylpyridine derivatives for the saturated blue emission

To obtain a saturated blue phosphorescent material with a good color purity, we have synthesized the new blue emitting iridium complexes with 2, 6-difluoro-3-(4-methylpyridin-2-yl)pyridine (4-Me-dfpypy) as a main ligand. We expected that the LUMO energy levels of the complex might increase upon introduction of an electron donating group such as a methyl group to the pyridyl moieties of the ligand, leading to a wide energy gap of the complex to give the saturated blue emission. We have also introduced a variety of the ancillary ligands to the iridium center to compare the effect of the ancillary ligards on the emission of their complexes. The resulting iridium complexes, Ir(4-Me-dfpypy)3, Ir(4-Me-dfpypy)2(acac), Ir(4-Me-dfpypy)2(pic) and Ir(4-Me-dfpypy)2(trzl-CH3) where acac, pic, and trzl-CH3 represent acetylacetonate, picolinate, and 2-(5-methyl-2H-1,2,4-triazol-3-yl) pyridinate, respectively exhibited the blue emission at 451, 447, 440 and 425 nm in CH2Cl2 solution. The organic light emitting device (OLED) employing homoleptic Ir(4-Me-dfpypy), as the blue dopant was prepared and their electroluminescence was investigated. Ir(4-Me-dfpypy)3 exhibited the blue emission of CIE coordinates (0.22, 0.32).     

The phase transformation toughening and synergism in poly(butylene terephthalate)/poly(tetramethyleneglycol) copolymer-modified epoxies

The toughening of epoxy modified with poly(butylene terephthalate)/poly(tetra-methylene glycol) (PBT–PTMG) copolymers of various chemical composition was investigated. The fracture toughness of the brittle epoxy was highly enhanced by the inclusion of PBT–PTMG copolymer without loss of other intrinsic mechanical properties, such as modulus and yield stress. These modified epoxies also exhibited synergism in toughening. The remarkable enhancement and the synergism in fracture toughness of PBT/PTMG-modified epoxies is possibly due to the enhancement of the degree of phase transformation toughening, which is a result of the enhancement of the degree of perfectness of PBT spherulites in the presence of PTMG segments. The changes in micro-morphology of PBT/PTMG phases induced by the different chemical composition of copolymer is the most important cause of the dependency of the fracture energy on the processing variables, such as the relative PBT/PTMG composition and total amount of modifiers. Other toughening mechanisms, such as crack bifurcation, ductile fracture of PBT/PTMG phases, main crack-path alteration, and crack bridging, also contributed to toughness enhancement of the modified epoxies. © 1998 Chapman & Hall     

Ammonium nitrogen removal from slurry-type swine wastewater by pretreatment using struvite crystallization for nitrogen control of anaerobic digestion.

Precipitation of ammonium together with phosphate and magnesium is a possible alternative for lowering the nitrogen content of wastewater. In this study we examine the removal of ammonium nitrogen and phosphorus from slurry-type swine wastewater containing high concentrations of nutrients by the addition of phosphoric acid along with either calcium oxide or magnesium oxide, which leads to the crystallization of insoluble salts such as hydroxyapatite and struvite. The struvite crystallization method showed a high capacity for the removal of nitrogen when magnesium oxide and phosphoric acid were used as the magnesium and phosphate sources, respectively. When it was applied to swine wastewater containing a high concentration of nitrogen, the injection molar ratio of Mg2+:NH4+:PO4(3-) that gave maximum ammonium nitrogen removal was 3.0:1.0:1.5.     

Mechanical Properties,Morphologies, and Microstructures of Novel Electrospun Metallized Nanofibers

We report that the metal‐deposited single nanofibers can be successfully prepared by electrospinning and metallization. The tensile strength of the metal‐deposited single nanofibers as well as various non‐metallized polymeric nanofibers was investigated by recently developed tensile test machine. The tensile strength of 50 nm metal‐deposited single nanofibers was dramatically improved, which was much higher than that of pure polymer single nanofiber. The result is attributed to the formation of metallic hard‐coating layers onto the surface of single nanofibers. The tensile strength of the metal‐deposited single nanofibers was also depended on the types of metals (for instance, Cu, Ni, Sn, and Al) used for metallization. In addition, we investigated various annealing conditions, such as annealing temperature and time, and composition ratio of two metals (Cu and Ni), in order to find out optimum annealing process for the formation of metal alloy nanofibers. The characterization of the metallized nanofibers was conducted by field emission scanning electron microscope (FE‐SEM) and X‐ray diffraction (XRD).     

High performance fractional motion estimation in h.264/avc based on one-step algorithm and 8×4 element block processing

Conventional two-step algorithm, long latency of interpolation and various motion vectors are three factors that mainly induce high computation complexity of fractional motion estimation and also prevent it from encoding high-definition video. In order to overcome these obstacles, a high performance fractional motion engine is proposed in this paper with three techniques. First, based on high correlation between motion vector of a block and its up-layer as well as relationship of integer candidates, one-step algorithm is proposed. Second, an 8×4 element block processing is adopted, which not only eliminates almost redundancies in interpolation, but also still ensures hardware reusability. Finally, a scheme of processing 4×4 and 4×8 block with free of cycles is presented, so that the number of motion vectors can be reduced up to 59%. Experimental results show that the proposed design just needs 50% of gate count and 56% of cycles when compared with previous design while nearly maintaining the coding performance.