Artificial burrow preference by the Japanese crayfish Cambaroides japonicus

SUMMARY: Preference for artificial burrows by the endangered Japanese crayfish species Cambaroides japonicus was studied to improve its cultivation. The occupation of artificial burrows, which were made from straight polyvinyl chloride pipes of different internal diameters ( Y , mm), by crayfishes of different total lengths ( X , mm) was significantly ( P < 0.001, n = 56) described by a linear regression: Y = 0.49 X + 3.42 (19.0 ≤ X ≤ 70.2). Among burrows of different lengths [crayfish total length (TL) × 1, × 2, × 3, and × 4], crayfishes significantly preferred burrows that were greater than TL × 3 ( P < 0.001, n = 588).     

Thermal behavior of beta-1 subunits in lignin: pyrolysis of 1,2-diarylpropane-1,3-diol-type lignin model compounds

1,2-Diarylpropane-1,3-diol-type lignin model compounds, 1,2-bis(4-hydroxy-3-methoxyphenyl)propane-1,3-diol (1) and 1-(3,4-diethoxyphenyl)-2-(4-methoxyphenyl)propane-1,3-diol (2), were pyrolyzed at 500 degrees C for 4 s to clarify the thermal behavior of beta-1 subunits in lignin. Products were monitored by gas chromatography/mass spectrometry. The cleavage of the Calpha-Cbeta bond to produce benzaldehydes such as 4-hydroxy-3-methoxybenzaldehyde (9) and phenylethanals as the counterparts such as 4-hydroxy-3-methoxyphenylethanal (10) occurred in pyrolyses of both 1 and 2. In pyrolysis of 1, an oxetane pathway leading to the formation of Z/E-stilbenes without the gamma-CH2OH group such as Z/E-4,4'-dihydroxy-3,3'-dimethoxystilbene (3) was predominant. In pyrolysis of 2, the oxetane pathway was minor, while pathways producing a dimer with a =CgammaH2 group by loss of water and a dimer with an alpha-carbonyl group were predominant. Pyrolysis of Japanese cedar wood provided 3 and 10 in approximately 0.8% and 0.6% yields, respectively, based on the Klason lignin content, while pyrolysis of a guaiacyl bulk dehydrogenation polymer gave them in a very small amount.     

Safety of the tram car for slopes examined by stress analysis of the ground structure

For monorail systems, it is very important to ensure the safety of the ground structure. We developed a tram car for slopes that utilizes the mechanism of the monorail and analyzed the stress of the ground structure that had double rails. First, we divided the ground structure into seven components, and formulated a procedure for calculating the stress of the ground structure. As a result, the stress that acts upon the main rail and the main rail connecting part was near the allowable stress, and each calculated value was within the allowable stress. We measured the stress by running the vehicle, and compared the measured values with the calculated values. As a result, some measured values were larger than the calculated values. However, the ratio of measured value to allowable stress was 90% or less. Finally, we calculated the static loading coefficient for each part, results of which were as follows: main and subrail: 1.1; rail connection part and prop foundation part: 1.0; rail installation part: 1.3. In the recalculations, it became clear that the recalculated values exceeded the allowable stresses. These results suggest that we need to review the ground structure materials.     

Changes in myoglobin content and proximate compositions of the dorsal ordinary muscles of full-cycle cultured Pacific bluefin tuna Thunnus orientalis (Temminck et Schlegel) with body size

We investigated the changes in myoglobin (Mb) content and proximate compositions of the cephalad parts of the dorsal ordinary muscles (Ce‐DOM) of full‐cycle cultured (FC) Pacific bluefin tuna [body length: 42.6–115.4 cm, body weight (BW): 1.7–38.4 kg, killed from July 2004 to October 2005]. The Mb content of Ce‐DOM increased (P<0.01) until a BW of 7.0 kg was reached. However, the Mb content of Ce‐DOM had a wide variety above a BW of 7.0 kg. On the other hand, the moisture, protein and ash contents of Ce‐DOM of FC tuna decreased (P<0.05 and 0.01) with an increase in BW. However, the lipid content of Ce‐DOM increased gradually above about a BW of 20.0 kg. Furthermore, the Mb content in protein of the Ce‐DOM of FC tuna increased with an increase in BW. These results indicated that the increase in Mb content of Ce‐DOM of FC tuna was not related to changes in proximate composition between a BW of 1.7 and 38.4 kg.     

Evaluation of genetic variation among wild rice populations in Cambodia

A total of 448 samples in five natural populations of wild rice (Oryza rufipogon) were collected in Cambodia. They were examined using 12 SSR and two chloroplast markers to evaluate the degree of variation among populations and the genetic structure within populations. In the two annual populations, the number of plants with homozygous alleles at all 12 SSR loci were high (66.3% and 79.5%), suggesting that these plants propagate mainly through self-pollination. In the three perennial populations, no individuals had all homozygous genotypes, but redundant genotypes resulted from clonal propagation were observed. Percentages of the redundant genotypes were highly varied (3.6%, 29.2% and 86.0%). This may be due to the different stable levels of environmental conditions. As for chloroplast genome, most of the wild plants showed the same chloroplast types as most Indica-type cultivars have. However, plants with different chloroplast types were maintained, even in the same population. In tropical Asian countries, many wild rice populations were observed under similar ecological conditions examined in this study. Therefore, the present results concerning population structure will be important to further elucidate genetic features of wild rice, and will also give strong clues to utilize and conserve wild natural genetic resources.     

Naturally occurring antifungal agents against Zygosaccharomyces bailii and their synergism

Polygodial was found to exhibit a fungicidal activity against a food spoilage yeast, Zygosaccharomyces bailii, with the minimum fungicidal concentration (MFC) of 50 microg/mL (0.17 mM). The time-kill curve study showed that polygodial was fungicidal at any growth stage. The primary action of polygodial comes from its ability to disrupt the native membrane-associated function of integral proteins as nonionic surface active agents (surfactants) followed by a decrease in plasma membrane fluidity. The fungicidal activity of polygodial was increased 128-fold in combination with a sublethal amount (equivalent of 1/2 MFC) of anethole and vice versa relative to the fungicidal activity of anethole. The fungicidal activity of sorbic acid was enhanced 512-fold in combination with 1/2 MFC of polygodial. Conversely, the fungicidal activity of polygodial was enhanced 128-fold in combination with 1/2 MFC of sorbic acid.     

Identification of a novel cytotoxic protein, Cry45Aa, from Bacillus thuringiensis A1470 and its selective cytotoxic activity against various mammalian cell lines

Parasporal inclusion proteins produced by Bacillus thuringiensis strain A1470 exhibit strong cytotoxicity against human leukemic T cells when activated by protease treatment. One of the cytotoxic proteins was separated by anion exchange chromatography and gel filtration chromatography and designated Cry45Aa. Its gene was then expressed in recombinant Escherichia coli, in which the Cry45Aa precursor was accumulated in an inclusion body. It was solubilized in sodium carbonate buffer and processed with proteinase K, and cytotoxic activities of the protein against various mammalian cell lines were evaluated using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide assay. The protein exhibited high cytotoxic activity against CACO-2, Sawano, MOLT-4, TCS, and HL60 cells and moderate activity against U-937 DE-4, PC12, and HepG2 cells. On the other hand, the EC50 values against Jurkat, K562, HeLa, A549, Vero, COS-7, NIH3T3, CHO, and four normal tissue cells (human primary hepatocyte cells, UtSMC, MRC-5, and normal T cells) were >2 microg/mL.     

New Eyes for Looking Back to the Past and Thinking of the Future

While environmental pollution and destruction of nature are expanding on a global scale, it is becoming ever more important to comprehend the influence of human activities on the global environment and to consider the future. How does acid pollution caused by human activities influence the environment? When and how has it progressed, what is the situation now and how is it likely to shift in the future? Humans are creatures destined to consume energy and resources in the biosphere. Although we know that drastic and disproportionate increases in the consumption of natural and non-renewable resources have greatly altered the biosphere, reliable data on the actual levels of pollution existing in the past are scarce or lacking. Many methods involving natural or artificial materials have been used for historical monitoring, but there is still a need for new ones, which will allow us to look at the past and think of the future. The newly proposed scientific use of tree bark pockets as pollution time capsules gives us "new eyes" for historical monitoring of atmospheric pollution and changes in the global environment.

     

Iron content of rat serum ferritin.

The serum ferritin concentration was significantly higher in female than in male rats, reflecting higher iron stores in females than in males. The mean iron/protein ratio of serum ferritin was 0.018+/-0.008 (SD) (microg of Fe/microg of protein) in female rats and 0.011+/-0.011 in male rats, being much lower than that of liver ferritin (0.233+/-0.014 in females and 0.227+/-0.020 in males). Iron loading of rats significantly increased serum ferritin concentration, but did not influence the iron content of serum ferritin. These results indicate that rat serum ferritin contains only a small amount of iron independent of body iron stores.