Bioconcentration and elimination of bis(tributyltin)oxide (TBTO) and triphenyltin chloride (TPTC) in several marine fish species

Pagrus major, Mugil cephalus and Rudarius ercodes were exposed to bis(tributyltin)oxide (TBTO) and triphenyltin chloride (TPTC) for 8 weeks in a flow-through aquarium system. The bioconcentration factors (BCFs) of TBTO and TPTC and the elimination rate constant of TBTO for these fish were determined. The BCF of TBTO ranged from 2400 to 11,000 depending on the fish species and the concentration in the rearing seawater. Out of the three, P. major had the smallest elimination rate constant (0.024 day⁻¹) and bioconcentrated the largest amount of TBTO (BCF: 9400–11,000). On the other hand, the BCF of TPTC of the two fish species examined was similar: 3100–3300 for P. major and 4100 for R. ercodes. These BCFs of TBTO and TPTC of P. major were larger than the values previously reported. TBTO and TPTC were the least accumulated in muscle among the tissues and organs of P. major examined, and no correlation was found between the lipid content and the accumulated TBT or TPT content.     

Mapping of the rat SM22 gene to chromosome 8q24: a candidate for high blood pressure and cardiac hypertrophy

We describe two cases of fulminant thrombotic thrombocytopenic purpura (TTP) in unusual association in systemic lupus erythematosus (SLE) patients. In our two SLE patients the exceptionally rapid fatal course of TTP made any therapeutic intervention impossible.     

Dehydrogenative cracking of n-butane using double-stage reaction

Dehydrogenation-cracking double-stage (tandem) reaction of n-butane was studied using a Pt-Sn type dehydrogenation catalyst and a cracking catalyst (rare earth-loaded HZSM-5). n-Butane was firstly dehydrogenated to n-butene (1- and 2-butene) over the Pt-Sn catalyst loaded at the upper part of the reactor. Then n-butene was successively converted to ethylene and propylene over the cracking catalyst loaded at the lower part of the reactor. The yield of light olefins (ethylene+propylene) was 58% at 650 °C. The key to obtaining ethylene and propylene in high yield was to determine how the bimolecular reactions of olefins to aromatic and heavier products can be inhibited. It was proved that the loaded rare earths played an important role in inhibiting the bimolecular reactions.     

Photorealistic real‐time rendering of spherical raindrops with hierarchical reflective and refractive maps

Synthesizing rainy images is a common challenge found in film, game engines, driving simulators, and architectural design. Simulating light transport through a raindrop's optical properties is a view‐dependent problem, and large quantities of raindrops are required to produce a plausible rainy scene. Accurate methods for rendering raindrops exist but are often off‐line techniques that are cost prohibitive for real‐time applications. Most real‐time solutions use textures to approximate the appearance of moving raindrops as streaks. These approaches produce plausible results but do not address the problem of temporal effects such as slow‐motion or paused simulations. In such conditions, streak‐based approximations are not suitable, and proper raindrop geometry should be considered. This paper describes a straight‐forward approach for rendering raindrops in such temporal conditions. The proposed technique consists of a preprocessing stage that generates a raindrop mask and a run‐time stage that renders raindrops as screen‐aligned billboards. The mask's contents are adjusted on the basis of the viewpoint, viewing direction, and raindrop position. The proposed method renders millions of raindrops at real‐time rates in current graphics hardware, making it suitable for applications that require high‐visual quality without compromising performance. Copyright © 2011 John Wiley & Sons, Ltd.     

Very high cycle fatigue properties of bearing steel under axial loading condition

It has been observed to appear a step-wise or duplex S–N curve under the test of rotary bending fatigue using high strength steel. This behavior was caused by the transition of fracture mode from surface-induced fracture to subsurface inclusion-induced fracture. The aim of this study is to clarify the S–N characteristic under an axial loading fatigue in the very high cycle fatigue regime. In order to investigate the mean-stress effects, fatigue tests were carried out in air at room temperature under three applied stress ratios of ?1, 0 and 0.5 using a hour-glass shaped specimen of high carbon–chromium bearing steel, JIS SUJ2. From the results, three types of fracture mode were observed on the fracture surface, such as surface-induced fracture, subsurface inclusion-induced fracture without granular bright facet (GBF) area and that with GBF area around an inclusion. Fatigue lifetime for transition in the fracture mode depended on the applied stress ratio. Shape of the S–N curve was a smooth and continuous under three testing conditions in spite of the occurrence on the three types of fracture. Detail discussion for fatigue fracture behavior was made through the observation of fracture surface and from point in view of the fracture mechanics. In addition, an effect of residual stress in the specimen surface layer on the transition of fracture mode was discussed and compared with the experimental results.     

Biochemical properties of acid-soluble collagens extracted from the skins of underutilised fishes

Acid-soluble collagens (ASCs) were extracted from the skins of several underutilised fishes, namely dusky spinefoot (Siganus fuscescens), sea chub (Kyphosus bigibbus), eagle ray (Myliobatis tobijei), red stingray (Dasyatis akajei) and yantai stingray (Dasyatis laevigata). The yields of the ASCs from skins of dusky spinefoot and sea chub were about 3.4–3.9%, and from ray species were about 5.3–5.7%, on a dry weight basis. According to the electrophoretic pattern, ASCs consisted of two different α-chains (α1 and α2) and were classified as type I collagen. However, the molecular weights of α2-chain for ray species were lower than those of bony fishes. ASC from ray species contained a higher content of imino acids than those from dusky spinefoot and sea chub. The denaturation temperatures (T_d) of ray species were about 33 °C, which was about 5 °C higher than those of dusky spinefoot and sea chub. The high T_d of ray species suggested the possibility of its utilisation as a substitute for mammalian collagen.     

Integrity assessment of the high temperature engineering test reactor (HTTR) control rod at very high temperatures

The high temperature engineering test reactor (HTTR) is the first high temperature gas-cooled reactor (HTGR) in Japan with a reactor outlet coolant temperature of 950°C at high temperature test operation. The HTTR contains 16 pairs of control rods for which Alloy 800H is chosen of the metallic parts. Because the maximum temperature of the control rods reaches about 900°C at reactor scrams, structural design guideline and design material data on Alloy 800H are needed for the high temperature design. The design guideline for the HTTR control rod is based on ASME Code Case N-47-21. Design material data is also determined and shown in this paper. Under the guideline, temperature and stress analysis was conducted, and it is confirmed that the target life of the control rods of 5 years can be achieved.     

Characterization of stress in doped and undoped polycrystalline silicon before and after annealing or oxidation with laser raman spectroscopy

Stress in polycrystalline silicon (poly-Si) was characterized with laser Raman spectroscopy. Effects of diffusion of phosphorus, annealing and oxidation on stress were especially studied. Relaxation of undirectional stress by annealing and oxidation was observed. Undirectional stress was relaxed by heavy doping of phosphorus which made a grain size larger. Compressive stress increased, however, by oxidation in poly-Si with a smaller grain size.