Novel repeated batch operation for flash fermentation system: Experimental data and mathematical modelling

A novel repeated batch operation mode was proposed for ethanol fermentation, where the fermenter beer was periodically exchanged between the fermenter with biomass recycle and the distillation unit, to promote the selective removal of ethanol. Using the mathematical model developed, as based on the experimental results, the optimal operation of the proposed method was shown to attain high performance, with a productivity of about 12 g dm⁻³ h⁻¹ and a product concentration of 400 g dm⁻³.     

Role of Cu film texture in grain growth correlated with twin boundary formation

To understand the role of Cu film texture in grain growth at room temperature (RT) in relation to twin boundary formation Cu films were deposited on various barrier materials and the Cu film texture was investigated by X-ray diffraction. Cu grain growth was rapid on a barrierless SiO₂/Si substrate and very slow on a Ta barrier due to strong (1 1 1) texture. The growth rate and the average grain diameter after being kept at RT for up to ∼60 days were maximum at a (2 0 0)_Cu peak to (2 2 2)_Cu peak area ratio of ∼1.0, where {1 1 1}, {1 0 0} and {5 1 1} grains coexisted. Such coexistence of three or more orientations of grains is essential in facilitating Cu grain growth at RT. Similarly, the average twin boundary (TB) density was maximum when Cu grain growth was facilitated. TB formation in nano-sized Cu grains was not controlled by grain size, but due to grain growth. The TB could be annealing twins caused by irregularities in the stacking sequence during relatively fast grain growth. The Cu film texture is concluded to be determined at the beginning of deposition, and the wettability of various barrier materials by the Cu films plays a key role in determining the film texture.     

Piecewise affine systems modelling for optimizing hormone therapy of prostate cancer

Prostate cancer is one of the most common malignant neoplasms in men with an overall incidence of approximately 15 per cent during the normal life span. Androgen-deprivation therapy (hormone therapy) is an effective treatment of this disease when progressed to an advanced stage. Despite impressive responses, such treatment when applied on a continuous basis is not curative and eventually culminates in androgen-independent disease. On the other hand, intermittent androgen suppression (IAS) was first conceived as a potential way of delaying progression to androgen-independence, in addition offering the possibility of reducing adverse effects and improving the quality of life. Although the validity of this approach has been confirmed in several clinical studies, the optimal scheduling of the cycles of on- and off-treatment remains to be explored. In the present article, we show that IAS lends itself to mathematical modelling with hybrid dynamical systems and that the model we have developed can be used to select the best strategy for keeping prostate cancer in an androgen-dependent state as long as possible. Our results also suggest that the current way of using IAS exceeds what is necessary for optimal control; in fact, we have found that to achieve optimal control, the amount of therapy (dose and duration of drugs) can be reduced by a factor of one half.     

Gaze direction modulates the disengagement of attention from facial expression in 10-month-olds.

This study investigated whether the disengagement of attention from facial expression is modulated by gaze direction in infants. To this end, we measured the saccadic reaction time required for the 10-month-olds to disengage their attention from angry and happy expressions combined with either straight or averted gaze. The 10-month-olds' disengagement of their attention from happy faces was modulated by gaze direction. This finding indicates that gaze direction strongly influences infants' allocation of attention to facial expressions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hot explosive compaction of diamond powder using cylindrical geometry

Diamond powders were attempted to be consolidated at elevated temperature using an explosive compaction technique employing a cylindrical configuration. A compacted diamond sample recovered from the center of a cylinder, close to the end plug made of stainless steel showed high hardness and tight interparticle bonding between the diamond powders. The sample was characterized on the basis of X-ray diffraction patterns. No graphitization was observed due to heating or compaction, and the hot compacted sample was highly strained by intensive deformation at elevated temperature.     

Characterization and adsorption properties of organosilyl aluminophosphate hybrids

Organosilyl aluminophosphates (AlPOs) were prepared by using organosilyl agents such as methyltriethoxysilane and ethyltriethoxysilane, and characterized by XRD, TG, ICP, CHN elemental analysis, NMR, SEM, and TEM, and gas adsorption properties of them were investigated. The organosilyl agents formed amorphous phases on the AlPO crystal surfaces. The amorphous phases play two roles; changing the size of pore and forming the new pore spaces. The change of pore size induces molecular sieving phenomenon for small molecules. The pore in the amorphous phase is more effective for i-butane than toluene molecules, although they have the similar molecular sizes each other.     

Shock-consolidated TiO2 bulk with pure anatase phases fabricated by explosive compaction using underwater shockwave

Titanium dioxide (TiO₂) bulk with pure anatase phases was fabricated by an explosive compaction technique using an underwater shockwave. Dynamic shock pressure of 6 GPa was used to consolidate anatase TiO₂ powders. Its microstructural, crystalline structural and photocatalytic characteristics were observed and measured by various techniques, such as X-ray diffraction (XRD), scanning electron microscopy (SEM) and photocatalytic activity measurement system. It was confirmed that the relative density of anatase TiO₂ compact is about 96% (3.73 g/cm³) of the theoretical density (3.89 g/cm³) and a strong surface bonding between particles is formed by a shock energy. In X-ray diffraction analysis, high purity anatase phases, broadened peaks due to lattice defects and decreased crystallite size were found. For the photocatalytic activities, the anatase TiO₂ compact was quite excellent compared to the commercial sintered TiO₂ bulk.     

Serial Changes of Serum Growth Factor Levels and Liver Regeneration after Partial Hepatectomy in Healthy Humans

This study aimed to investigate the associations of the serial changes of serum levels of various growth factors with liver regeneration after hepatectomy in healthy liver donors. Sixteen healthy liver donors who underwent conventional liver resection were included. Serum levels of various growth factors before hepatectomy and on postoperative day (POD) 1, 3, 5 and 7 were measured. Liver volume data calculated by multi-detector computed tomography using workstation. The ratio of remnant liver volume on POD 0 to liver volume before the operation was 51% ± 20%. The ratio of liver volume on POD 14 to liver volume on POD 0 were inversely correlated with remnant liver volume on POD 0 (r = −0.91). The ratio of liver volume on POD 14 to liver volume on POD 0 were significantly correlated with serum hepatocyte growth factor (HGF) levels on POD 1 (r = 0.54), serum leptin levels on POD 1 (r = 0.54), and serum macrophage colony-stimulating factor (M-CSF) levels on POD 5 (r = 0.76) and POD 7 (r = 0.80). These results suggest that early-phase elevation of serum levels of HGF, leptin and M-CSF may be associated with the acceleration of liver regeneration after hepatectomy in humans.     

Soft Nanotubes with a Hydrophobic Channel Hybridized with Au Nanoparticles: Photothermal Dispersion/Aggregation Control of C60 in Water

Simple glycolipid N‐alkaroyl‐β‐D‐glucopyranosylamine 1(n) selectively self‐assembles into sheets in water, nanotubes in alcohols, and helical nanocoils in toluene. All self‐assemblies consist of bilayer membranes in which 1(n) packed in an interdigitated fashion. The outer surface of the sheet is covered with the hydrophilic glucose headgroup of 1(n), whereas those of the nanotube and helical nanocoil are covered with the hydrophobic alkyl‐chain tail of 1(n). Heat treatment of the nanotube in the presence of water induces a rearrangement of the molecular packing of the outermost surface that allows the nanotube to become an effective nanocontainer for the dispersion of fullerene (C60) in water, a result of the ability of the hydrophilic outer surface of the nanotube and the hydrophobic nanochannel to encapsulate C60. The nanotube also exhibits photothermal characteristics after being hybridized with Au nanoparticles (AuNPs). The photothermal effect of the AuNPs allows the nanotube to unfold its tubular morphology and leads to compulsive release of the encapsulated C60 to the bulk water. Application of other nanotubes with similar photostimulated transformation ability should facilitate control of the dispersion/aggregation of other carbon nanomaterials, functional aromatic compounds, and drugs with low solubility in water.     

Low-temperature synthesis in vacuum of c-axis oriented ferroelectric YMnO3 thin films using alkoxy-derived precursors

Abstract

Hexagonal YMnO₃ thin films were prepared on Pt(111)/TiO_x/SiO₂/Si and Pt(111)/Al₂O₃(0001) substrates using alkoxy-derived precursor solutions. The films were prepared by spin coating the YMnO₃ precursor solutions and then, the films were calcined and crystallized via rapid thermal annealing in oxygen or vacuum ambient. The annealing conditions and substrates were critical for crystallization of ferroelectric YMnO₃ films. When annealed in vacuum, the films both on Pt(111)/TiO_x/SiO₂/Si and Pt(111)/Al₂O₃(0001) substrates crystallized to hexagonal YMnO₃ and the orientation depended on the substrates. The film on Pt(111)/Al₂O₃(0001) had c-axis orientation and the film on Pt(111)/TiO_x/SiO₂/Si had no preferred orientation. In addition, it was found that crystallization behavior, orientation and morphology of YMnO₃ films on Pt(111)/TiO_x/SiO₂/Si substrates depended on the annealing condition. The heat-treatment in vacuum at initial stage for crystallization affected the restraint of perovskite phase and formation of hexagonal phase. The following heat-treatment in oxygen promoted the c-axis orientation and grain growth. The optimum annealing procedure for crystallization of the c-axis oriented YMnO₃ films on Pt(111)/TiO_x/SiO₂/Si was addressed.