Analyses with latest major nuclear data libraries of the fission rate ratios for several TRU nuclides in the FCA-IX experiments

In the 1980s, a series of integral experiments was conducted in FCA-IX assemblies with systematically changed neutron spectra covering from the intermediate to fast ones. The experiments provide systematic data of central fission rates for TRU nuclides containing minor actinides, ²³⁷Np, ²³⁸Pu, ²³⁹Pu, ²⁴²Pu, ²⁴¹Am, ²⁴³Am, and ²⁴⁴Cm. Regarding the fission rate ratios relative to ²³⁹Pu, benchmark models had been recently developed for validation of nuclear data for the TRU's fission cross sections. In this paper, the latest major nuclear data libraries, JENDL-4.0, ENDF/B-VII.1, and JEFF-3.2, are compared on the benchmark models. For the libraries, the analyses by a Monte Carlo calculation code show obvious overestimations particularly for the fission rate ratios of ²⁴⁴Cm to ²³⁹Pu. Additionally, a large discrepancy about by 20% between the libraries is revealed for the fission rate ratio of ²³⁸Pu to ²³⁹Pu measured in the intermediate neutron spectrum. The causes of discrepancies are furthermore clarified by sensitivity analyses.     

Type I collagen from the skin of ornate threadfin bream (Nemipterus hexodon): Characteristics and effect of pepsin hydrolysis

Type I collagen from the skin of ornate threadfin bream (Nemipterus hexodon) was purified and characterised. Purified type I collagen contained [α1(I)]₂α2(I) as the dominant component with the co-presence of α1(I)α2(I)α3(I). It was rich in glycine and alanine with high content of imino acids (188 residues/1000 residues). The maximum transition temperature (T_m) and the total denaturation enthalpy (ΔH) of purified type I collagen was 33.35 °C and 0.819 J/g, respectively. The isoelectric point (pI) of purified type I collagen was estimated to be 6.40. After hydrolysis of purified type I collagen using pepsin, the band intensity ratios of α1/α2-chains were increased (P < 0.05). The cross-linked components were effectively hydrolysed by pepsin 1 and 2 from skipjack tuna stomach and porcine pepsin at 4 °C without the cleavage of β- and α-chains. At 50 °C, they were more susceptible to porcine pepsin hydrolysis, followed by pepsin 2 and 1, respectively.     

Docosahexaenoic acid levels in the lipids of spotted mackerel Scomber australasicus

The lipid and FA compositions of various organs and of the stomach contents of Scomber australasicus were analyzed. DHA was characteristically the major FA of all the major lipid classes of all organs except for liver TAG. The mean DHA contents of the various organs accounted for more than 17% of the total FA (TFA), whereas those in the stomach contents, originating from the prey, fluctuated and were generally low. In particular, the DHA levels in the TAG from all organs of S. australasicus accounted for up to 17% of TFA, even though it is a neutral depot lipid. S. australasicus contained markedly high levels of DHA, even though it is a small-sized Scombridae species, and its high levels of DHA were close to those in large-sized highly migratory tuna species. Furthermore, DHA levels in its muscle TAG were consistently high, compared with those in the visceral TAG, which might be directly influenced by the prey lipids. These phenomena suggest that long-distance migration has a close relationship with high accumulation of DHA in fish tissues, since S. australasicus is reported to migrate in offshore water, similar to highly migratory tuna species. Additionally, the physiological selective accumulation of DHA in the muscle during migration is caused by in vivo metabolism of FA in the vascular system, suggesting that DHA is poorly used as a source of migration energy, though it is provided abundantly through the prey lipids.     

Solution-stirring method improves crystal quality of human triosephosphate isomerase

We examined the effect of a solution-stirring method on human triosephosphate isomerase crystallization. The crystals diffracted to more than 1.4 A resolution, whereas those obtained by the normal vapour-diffusion technique diffracted to 2.8 A. These results clearly show that the solution-stirring method is valuable and useful for protein crystallization because of its effectiveness and simplicity.     

Characterization of gelatin films prepared from under-utilized blue shark (Prionace glauca) skin

Gelatin film from blue shark (Prionace glauca) skin was investigated in order to utilize what is one of the most serious marine wastes in Japan. Film properties from shark skin such as tensile strength (TS), elongation at break (EAB) were evaluated. The TS of gelatin film from shark skin was affected by the protein concentration (1, 2 and 3%) of the film-forming solution (FFS). TS of the film from a 2% protein FFS was the highest. EAB and water vapor permeability (WVP) increased with increasing FFS protein concentration. WVP of shark skin gelatin was evidently low as compared to gelatin films from other fish. An increase in the FFS protein concentration decreased transparency at almost all wavelengths. Furthermore, opacity at 280 nm was characteristically high as compared to films from bony fish skin. The addition of glycerol improved flexibility and enhanced the UV barrier property at 280 nm. However, transparency at the visible range and WVP increased with increasing glycerol content.From the above, it was suggested that shark skin gelatin film technology can be applied to pharmaceutical products or rich-fat food due to its excellent water and UV barrier properties.     

A Double Dissociation Between Mood States and Personality Traits in the Anterior Cingulate.

Neuroticism and extraversion are personality traits associated with negative and positive mood states, respectively, confounding trait and state factors that may affect brain responses to emotional stimuli. The authors dissociated these factors using fMRI and the emotional Stroop attention task: Anterior cingulate (AC) response to positive stimuli varied as a function of personality trait, but not mood state, whereas AC response to negative stimuli varied as a function of mood state, but not personality trait. Negative mood, but not personality trait, also increased the functional connectivity between AC and other regions. Variance in AC activation can thus be ascribed to an intersubject variable (extraversion) when responding to positive stimuli and an intrasubject variable (mood) when responding to negative stimuli. The former may explain stable differences between extraverts and introverts. The latter may provide an adaptive mechanism to expand an individual's dynamic range in response to potentially dangerous or threatening stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

High docosahexaenoic acid levels in both neutral and polar lipids of a highly migratory fish: <Emphasis Type="Italic">Thunnus tonggol</Emphasis> (Bleeker)

The lipid and FA compositions of various organs (light muscle, dark muscle, liver, pyloric cecum, and the orbital region) and of the stomach contents of a highly migratory fish species Thunnus tonggol (Bleeker) were analyzed. TAG and phospholipids (PE and PC) were the major lipid classes in the total lipids of T. tonggol. DHA was characteristically the major FA of all the major classes of all its organs except for only one case of liver TAG. The mean DHA contents of the various organs accounted for more than 20% of the total FA (TFA), even though it is a neutral depot lipid. However, DHA in the stomach contents, originating from their prey, fluctuated and was generally low. DHA levels were generally higher in a year (2000) when water temperatures were colder than in one when it was warmer (1998). Furthermore, DHA levels in muscle TAG were consistently high in spite of the fluctuation of those in the visceral TAG, which might be directly influenced by the prey lipids. This phenomenon suggests the physiological selective accumulation of DHA in the muscle, after the migration of the digested FA in the vascular system and absorption of the prey lipids in the intestine. In contrast, the FA composition of other species is generally variable and their DHA contents of TAG are usually less than 20% of TFA.     

Experimental verification of the `stability profile of mutant protein' (SPMP) data using mutant human lysozymes

The stability profile of mutant protein (SPMP) (Ota,M., Kanaya,S.and Nishikawa,K., 1995, J. Mol. Biol., 248, 733–738) estimatesthe changes in conformational stability due to single aminoacid substitutions using a pseudo-energy potential developedfor evaluating structure–sequence compatibility in thestructure prediction method, the 3D–1D compatibility evaluation.Nine mutant human lysozymes expected to significantly increasein stability from SPMP were constructed, in order to experimentallyverify the reliability of SPMP. The thermodynamic parametersfor denaturation and crystal structures of these mutant proteinswere determined. One mutant protein was stabilized as expected,compared with the wild-type protein. However, the others werenot stabilized even though the structural changes were subtle,indicating that SPMP overestimates the increase in stabilityor underestimates negative effects due to substitution. Thestability changes in the other mutant human lysozymes previouslyreported were also analyzed by SPMP. The correlation of thestability changes between the experiment and prediction dependedon the types of substitution: there were some correlations forproline mutants and cavity-creating mutants, but no correlationfor mutants related to side-chain hydrogen bonds. The presentresults may indicate some additional factors that should beconsidered in the calculation of SPMP, suggesting that SPMPcan be refined further.