Induction of apoptosis by diphlorethohydroxycarmalol isolated from brown alga,Ishige okamurae

The anti-cancer effect of diphlorethohydroxycarmalol (DC) isolated from Ishige okamurae, a brown alga, via the induction of apoptosis resulting from mitochondrial dysfunction was assessed in human promyelocytic leukemia (HL60) cells. The apoptotic mechanisms of DC induction on tumor cells were studied in this work for the first time. DCs were determined to evidence marked cytotoxicity on HL60 cells in a dose-dependent manner. The induction of apoptosis in HL60 cells by DC was evidenced by the accumulation of sub-G₁ cell population and nuclear condensation. Further investigations into the depletion of mitochondrial membrane potential (ΔΨ_m) determined that DC treatment induced apoptosis via the regulation of the expression of pro-survival and pro-apoptotic Bcl-2 family members. It was demonstrated that the anti-cancer activity of DC was mediated by apoptotic induction resulting from mitochondrial dysfunction. Our study results also indicated dysfunction and that DCs may constitute a new and promising agent for the treatment of human promyelocytic leukemia cells.     

Effect of progressive forming process and processing variables on the formability of aluminium bipolar plate with microchannel

A bipolar plate is one of the crucial components that strongly influence the power density of the proton exchange membrane fuel cell stack. Especially, an aluminium bipolar plate not only has better mechanical properties such as density, electrical resistivity and thermal conductivity but also has more corrosion resistance than bipolar plates made of stainless steel and graphite composites. Furthermore, the use of aluminium reduces the cost and weight of the plates, and the plates are easily machinable. This study presents the results of experiments conducted to investigate the feasibility of developing bipolar plates made of aluminium that consist of microchannels. This paper explains experimental investigations performed to investigate the formability of an aluminium sheet. The effects of forming velocity and die temperature on the microchannels in thin sheets of Al5052 having a thickness of 0.3 mm are investigated. The roundness of the core-die channels ranged from 0.3 to 0.1 mm, and the height is 0.6 mm. Formability tests are conducted for forming velocities of 0.1 and 1.0 mm/s and die temperatures in the range from room temperature to 300°C. The experimental results indicate the feasibility of the proposed technique for manufacturing the bipolar plates of aluminium.     

Improved efficiency of inverted organic solar cells using organic hole collecting interlayer

The device performances of inverted organic solar cells were improved by using hexaazatriphenylene-hexacarbonitrile (HAT-CN) as the organic interlayer for hole collection at the anode. The HAT-CN was effective to enhance the open circuit voltage and fill factor of the inverted organic solar cells by forming good interfacial contact with Al anode in inverted organic solar cells. The power conversion efficiency of the organic solar cells was improved from 0.36% to 2.09% by the HAT-CN hole collecting organic interlayer.     

Two-Dimensional Terahertz Photonic Crystals Fabricated by Wet Chemical Etching of Silicon

The fabrication of two-dimensional terahertz photonic crystals using wet chemical etching of high-resistivity silicon is described. Wet-etched photonic crystals with a sloped sidewall were fabricated in 16 × 10 square lattices with a period of 1430 μm and a height of 150 μm, and were bonded between two parallel Au-coated silicon wafers for tight confinement in the vertical direction. The formation of a photonic band gap at a frequency of about 0.1 THz with a width of 14 GHz is demonstrated by the experimental results and the numerical simulations of the transmission frequency spectrum for the transverse magnetic mode.     

Absorption kinetics of carbon dioxide into aqueous ammonia solution: Addition of hydroxyl groups for suppression of vaporization

Aqueous ammonia can act as an alternative absorbent for CO₂ removal, but it has high volatility and reduces the ammonia concentration. We analyzed the hydroxyl additives 2-amino-2-methyl-1-propanol (AMP), ethylene glycol, and glycerol to reduce the vapor pressure of ammonia solutions. In addition, absorption efficiency groups of aqueous ammonia solutions containing hydroxyl additives were investigated. The results show that the addition of AMP, ethylene glycol, or glycerol to NH₃ reduced the vapor pressure of the absorbent by 14.0%, 22.7%, and 75.2%, respectively. The reaction rate constants of aqueous NH3 containing AMP, ethylene glycol, and glycerol additives at 293, 303, 313 and 323 K are given by $k_{2,NH_3 /AMP} = 4.565 \times 10^5 \exp ( - 1396.5/T)$ , $k_{2,NH_3 /ehylene glycol} = 1.499 \times 10^6 \exp ( - 1978.7/T)$ and $k_{2,NH_3 /glycerol} = 7.078 \times 10^6 \exp ( - 2413.3/T)$ , respectively.     

Effect of processing parameters on tensile properties of hot-drawn Al 2011-T8

Despite the wide-spread industrial use of drawn Al 2011 products, only an extremely limited number of studies are available on the effect of drawing parameters on the tensile behavior. In this study, the microstructural evolution and the tensile behavior of Al 2011-T8 specimens were studied with drawing ratios varying from 10 % to 40 % at different drawing temperatures of 350, 400 °C and 450 °C, respectively. Only a marginal change in the tensile properties of Al 2011-T8 was observed, despite the significant change in grain size ranging from 33 μm to 243 μm with different drawing parameters. Detailed fractographic examination suggested that low-melting, soft Pb-Bi globules greatly influenced the tensile behavior of Al 2011-T8, surpassing the effect of grain size. Based on the fractographic and micrographic observations, the tensile behavior of hotdrawn Al 2011-T8 specimens is discussed in conjunction with the effects of different drawing ratios and temperatures.     

Results of a gallium phosphide photovoltaic junction with an AR coating under concentration of natural sunlight

A gallium phosphide (GaP) photovoltaic junction is grown by molecular beam epitaxy (MBE) on a GaP substrate. An anti-reflection coating of polymethyl methacrylate (PMMA) is applied and the cell is measured under concentrations of 1× and 10.7× in an outdoor setting. Efficiencies up to 2.6% and open circuit voltages up to 1.57 V are reported.     

Controlled fluorescence resonance energy transfer between ZnO nanoparticles and fluorophores in layer-by-layer assemblies

We controlled the fluorescence resonance energy transfer (FRET) between ZnO nanoparticles and rhodamine B (RB) within multilayered thin films prepared by the layer-by-layer (LbL) assembling method. Positively charged ZnO nanoparticles and RB-labeled poly(allyamine hydrochloride) (RB-PAH) were accurately incorporated into LbL assemblies of polyelectrolytes. The distance between ZnO nanoparticles and RB-PAH was adjusted by varying the number of layers of pure polyelectrolytes, leading to the controlled FRET from ZnO nanoparticles to RB-PAH.