Indigenous genetic lineages of Fagus crenata found in the Izu Peninsula suggest that there was one of refugia for the species during the last glacial maximum

Regions believed to be refugia are known to have lineages indigenous to the regions. The Izu Peninsula, where genus Fagus existed during the last glacial period, was focused on to survey chloroplast DNA of Japanese beech (Fagus crenata Blume) that grew there. DNA sequence analysis of chloroplast genome regions of about 14 kb revealed two new haplotypes, O and E-1, in F. crenata populations in the Izu Peninsula and adjacent regions. Both haplotypes were conceivably derived from haplotype E. The result of the genetic analysis in this study in combination with the result of pollen analyses performed in the past clearly showed that refugia for F. crenata existed in the Izu Peninsula, and that F. crenata now in growth are lineages indigenous to the region.     

Chemical structures of p-menthane monoterpenes with special reference to their effect on seed germination and termite mortality

A series of p-menthane monoterpenes was investigated to confirm any correlation between their bioactivity (effect on seed germination and termite mortality) and chemical structure. The germination percentages of Brassica rapa seeds at a concentration of 0.1 mg/Petri dish of (+)-pulegone, isopulegol, piperitone, (?)-dihydrocarveol, terpinen-4-ol and (?)-menthol were found to be 21.6, 27.3, 27.3, 29.1, 42.9 and 43.4, respectively. The lethal concentration 50 values of carvacrol, (+)-pulegone, thymol, (?)-menthol and (?)-terpinen-4-ol for termites (Reticulitermes speratus) were 0.34, 0.50, 0.65, 0.92 and 1.26 (mg/Petri dish), respectively. Of all the compounds tested, phenols produced the highest levels of termite mortality, with ketones and alcohols also showing bioactivity. An assessment of the bioactivity revealed that the presence of a phenol group was effective for termite mortality, with a carbonyl group also showing strong bioactivity. The presence of an alcohol or isopropyl group in a ring also contributed to the bioactivity, whereas the presence of an isopropenyl group at the same position, however, exhibited an inhibitory effect on seed germination. In conclusion, the bioactivity of the p-menthane monoterpenoids was dependent upon the presence and position of certain functional groups and the degree of saturation in the functional group of the side chain.     

Fruits are more sensitive to salinity than leaves and stems in pepper plants (Capsicum annuum L.)

The effects of NaCl stress on plant growth, gas-exchange, activity of superoxide dismutase (SOD), rate of lipid peroxidation, and accumulation of Na⁺ ion and sugar were investigated in leaves and fruits of pepper plants (Capsicum annuum L.). Especially, the gene expression of l-galactono-1,4-lactone dehydrogenase (GalLDH), which is the last enzyme of ascorbic acid (AsA) biosynthesis, and the relationships between AsA level and Na⁺ concentration in plant tissue were investigated with increasing salinity. Plants were treated with three treatments: the control (0 mM NaCl) and two salinity levels (50 and 100 mM NaCl) for 21 days under greenhouse conditions. Plant growth was markedly restricted due to the reduction of photosynthetic rate and the increase of Na⁺ accumulation in leaves with the increasing intensity of NaCl stress. Salinity had more effect on fruit growth comparing to leaf growth, suggesting that fruits could be more sensitive to salinity than leaves. In comparison with the control, salt stress significantly increased lipid peroxidation (as measured as malondialdehyde content) but decreased SOD activity in both fruits and leaves although the effect was larger in fruits; and the rate of the decrease in SOD activity was greater than that of the increase in lipid peroxidation. The AsA concentration transiently increased first 7 days but it slightly decreased from the initial level in the end of treatment day 21. The change in GalLDH gene expression was similar to AsA concentration. The accumulation of Na⁺, the reduction of AsA level at severe salinity stress were greater in fruits than in leaves; and AsA level had a negative relationship with Na⁺ concentration in both leaves and fruits. These results suggest that the difference in salt sensitivity between fruits and leaves in pepper plants can be related to the difference in inhibition of AsA synthesis, which in turn is probably due to the toxicity of extreme accumulation of Na⁺.     

基于3S的黄土高原北部土地沙化分析——以陕西省神木县为例

采用实地调查和遥感数据分析相结合的方式,分析黄土高原北部神木县的土地沙化变化趋势及社会背景因素,为草地沙化的有效遏制提供依据。结果表明,神木县的土地沙化呈“整体缩小局部扩展”趋势。1986-2004年,沙化土地面积减少了10%（750 km2）。土地沙化在地区间有很大差异,县西北部乡镇里沙化土地减少明显,而南部的黄土峁地区沙化土地有所增加。与社会统计资料对比分析后发现,耕地面积比例大、人均土地面积少的乡镇地区,土地沙化趋势明显。以上结果意味着农田利用对黄土峁地区土地沙化有很大影响,传统耕作方式的改变有助于遏制土地沙化。     

Artificial and natural cross breeding between Atlantic salmon and salmonids currently present in Japan

We evaluated the potential for hybridization between Atlantic salmon and salmonids currently present in Japan. We performed artificial and natural crosses and tested for hybridization using short interspersed elements. We documented the occurrence of hybrids and gynogenesis following artificial crossing. However, the survival rate of these offspring was low (<2 % to the fry stage). We were unable to obtain viable offspring from natural crosses of Atlantic salmon and chum salmon or masu salmon. Our results suggest that there is little risk of hybridization between Atlantic salmon and salmonids that are currently present in the wild in Japan. Furthermore, our results suggest that gynogenesis may occur naturally.     

Feeding fermented soybean meal diet supplemented with taurine to yellowtail Seriola quinqueradiata affects growth performance and lipid digestion

Feeding experiment was conducted to determine whether fermentation and taurine supplementation of soybean meal (SBM) fed to yellowtail improve growth performance and lipid digestion. Six diets were formulated and designated as SBM, SBM supplemented with taurine (SBM + T), SBM fermented by Bacillus spp. (FSBM1), SBM fermented by Lactobacillus spp. (FSBM2), FSBM2 supplemented with taurine (FSBM2 + T), and fish meal (FM). Yellowtail fingerlings with an initial body weight of 42 g were stocked in 200‐L tanks. The fish were fed, each diet was fed twice daily in two separate tanks for 8 weeks. Results showed that lipid digestibility of the SBM diet was significantly lower than that of the FM diet, but SBM diet lipid digestibility was improved by taurine supplementation and fermentation. Lipase activity in anterior intestinal digesta, lipid contents in liver and muscle, and bile acid concentrations in gallbladder and anterior intestinal digesta were significantly lower in fish fed SBM diet than in fish fed FM diet; these parameters were not significantly different between fish fed SBM + T, FSBM2, FSBM2 + T diets and FM diet. Although taurine supplementation or fermentation improved lipid digestibility compared with FM diet, growth parameters were only improved in the fish fed FSBM2 + T diet, indicating that apart from a lack of taurine, SBM contains other factors responsible for inferior growth of yellowtail. These factors can be partially eliminated by Lactobacillus spp. fermentation.     

Comparison of injectable robenacoxib versus meloxicam for peri-operative use in cats: results of a randomised clinical trial

The objective of this study was to evaluate the efficacy and tolerability of robenacoxib, a selective cyclooxygenase-2 inhibitor, for the treatment of post-operative pain and inflammation in cats. The study was a prospective, multi-centre, randomised, blinded, non-inferiority design clinical study to compare robenacoxib to meloxicam. Ninety-six cats undergoing surgery at eight centres in Japan were allocated randomly to receive a single s.c. injection of robenacoxib (2 mg/kg, n=67) or meloxicam (0.3 mg/kg, n=29) shortly before induction of anaesthesia. Most cats underwent soft tissue surgery (n=87), mainly ovariectomy (n=68). Post-operative pain and inflammation were assessed at 3, 8 and 22 h after recovery from anaesthesia using numerical rating scales. For the primary efficacy endpoint (total clinician score), robenacoxib had significantly better efficacy than meloxicam, the relative efficacy ratio being 1.47 (95% confidence interval 1.19-1.78, P=0.0003). For the secondary efficacy endpoints, robenacoxib was superior to meloxicam when assessed on the basis of posture, behaviour, pain on palpation and overall pain control, while meloxicam was superior with respect to wound heat. No cat in either group required rescue analgesia therapy. In tolerability assessments, pain during injection and pain and inflammation at the injection site 22 h after recovery from anaesthesia were rated significantly less with robenacoxib compared to meloxicam. Both treatments were well tolerated on the basis of clinical observations and blood tests, with no significant differences between groups. In conclusion, single pre-operative administration of robenacoxib was well tolerated and had superior efficacy to meloxicam in reducing post-operative pain in cats.     

日本山地森林小流域悬移质泥沙研究

以日本山地源头森林小流域为研究对象,利用泥沙自动取样器和自计水位计,研究了悬移质泥沙的输出过程及其与洪水过程间的关系.研究结果表明,该森林流域的泥沙来源主要是林道、沟道、沟道两边裸露地;河川径流中悬移质泥沙浓度与总泥沙浓度间有很好的相关性;降雨时悬移质泥沙浓度随流量过程的变化呈现出顺时针变化的套索;悬移质泥沙的输出过程属于波浪式变化;悬移质泥沙浓度最大值与洪峰流量几乎同时出现,属同步型;悬移质输沙量主要取决于10 min最大雨量;场降雨量对悬移质输沙量的贡献较大;单场大暴雨造成的悬移质输沙量占全年输沙量的5％左右;悬移质年输沙量的30％是由为数不多的几场降雨造成的.      

Structure and activity of soil-inhabiting methanotrophic communities in northern forest of Japan

In a Japanese forest, CH₄ uptake rate and methanotrophic community structure in the soil were investigated at four sites of different vegetation. At two of these sites, undergrowth was dominated by Sasa senanensis, and that of another was dominated by Sasa kurilensis. At the rest site, undergrowth had been removed artificially. The tree-layer composition differed between the two sites with S. senanensis, but tree layer of the other two sites were dominated by the same species. At the site lacking undergrowth, observed CH₄ uptake rate was twice as high as that at the other sites. Under laboratory conditions, soil sample from the site lacking undergrowth exhibited CH₄ consumption rate higher than that of the adjacent site with the same dominating tree species. The community structures of methanotrophs were investigated with denaturing gradient gel electrophoresis (DGGE) of the gene encoding particulate methane monooxygenase (pmoA). The banding patterns observed were different depending on the type of undergrowth vegetation. The sequences of the DGGE bands were closely related to each other and belonged to the “upland soil cluster alpha” (USCα). These results imply possible close relationship between the undergrowth vegetation and methanotrophic communities in forest soils.