Transverse shape analysis of xylem ground tissues by Fourier transform image analysis I: trial for statistical expression of cell arrangements with fluctuation

Periodic cell arrangements of tracheids in Cryptomeria japonica and Agathis sp., and that of wood fibers in Magnolia obovata were examined by Fourier transform image analysis (FTIA). The angular distribution functions on power spectral patterns (PSPs) transformed from the dot maps were traced. As well as this conventional method, we developed the line convolution method and domain transformation for more correct analysis of radial and tangential arrangements. Cell arrangements became clear in Cryptomeria and Agathis. Fluctuations were expressed by the standard deviation (σ) or the relative standard deviation (σ_r) so that we could compare the characteristics of both woods. In Cryptomeria, the most provable distance between tracheids along radial files was 36.7 µm with 17% fluctuation, whereas the tangential interval was 28.3 µm with σ_r of 24%. In Agathis, the radial diameter was 35.1 µm with σ_r of 23% and the tangential interval was 41.5 µm with σ_r of 23%. In Magnolia, the maximal periodicity of wood fibers was 15.8 µm and 20.5 µm along and between radial files, respectively, although the fluctuations could not be estimated because of the remarkable interruptions by numerous vessels.     

Effects of the lateral growth rate on wood quality parameters of Eucalyptus grandis from different latitudes in Brazil and Argentina

Climate change resulting from increased atmospheric carbon dioxide (CO₂) and shortages of fossil fuels such as petroleum are major problems worldwide. Under these conditions, demand for woody biomass resources is increasing. We investigated the feasibility of using fast-growing Eucalyptus grandis for material production. Samples of E. grandis were collected from four plantations in different latitude divisions, including tropical and subtropical Brazil and subtropical Argentina. Various xylem qualities were measured and related to the lateral growth rate. Lateral growth rate did not significantly affect the longitudinal released strain of the surface growth stresses or the xylem density at any of the sampling sites. Higher lateral growth rate, higher values of xylem density, and lower absolute values of the released strain were observed in plantations closer to the equator. Higher growth rates in tropical climate promote longer fiber length. In subtropical plantations, smaller diameter trees will produce tension wood with smaller microfibril angles. Planting E. grandis closer to the equator thus produces higher quality wood than in plantations at lower latitudes.     

Similarities and differences in meat consumption patterns in Asia and Pacific-Rim countries

This study investigated consumer behavior towards meat across Asia and Pacific-Rim countries. Mail surveys were undertaken in 1994 and 1995. Data was obtained from 6197 households in Japan, the USA (mainland and Japanese–Americans in Hawaii), Australia, Thailand, Korea, Taiwan and China. The data were mainly analyzed using cluster analysis to determine the distance between each country and to classify countries into groups. Japanese respondents purchased beef more frequently than respondents from other countries. The average amount purchased on each occasion was far more for Australian respondents than for respondents from other countries, while Japanese purchased far less. Respondents in Japan, Korea, China and Australia thought beef was the most expensive meat, whereas lamb was thought to be the most expensive in the remaining countries. Chinese respondents indicated the highest consciousness of price indexes. The level of uneasiness about eating meat indicated by Asian respondents was relatively strong compared with respondents in Hawaii, the USA and Australia. Average ratings (semantic differential scale) on plans for future meat consumption were higher for beef than for other meats in Korea and China, whereas chicken was rated higher in the other countries. From the dendrogram, surveyed countries were classified into three groups: Japan, Taiwan and Korea; Thailand and China; and the USA, Japanese–Americans and Australia. Among them, the first and second clusters merged into a larger cluster, the 'Asian' group.     

Occurrence of rocket larkspur witches’ broom caused by “<Emphasis Type="Italic">Candidatus</Emphasis> Phytoplasma asteris” in Japan

In October 2001, a disease of rocket larkspur (Cosolida ambigua (L.) P. W. Ball et Heyw), characterized by witches’ broom, yellows and virescence of flowers, was found in Yakage Town in Okayama Prefecture. Electron microscopy revealed the presence of phytoplasma-like bodies in the phloem of diseased plants. The causal phytoplasma was identified as “Candidatus Phytoplasma asteris” based on 16S rDNA sequence analysis, and demonstrated to be acquired by the leafhopper Macrosteles striifrons. The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession number AB258330.     

Mineral composition in the holdfast of three brown algae of the genus Laminaria

SUMMARY: The mineral (Na, K, Ca, Mg, Fe, Mn and Zn) contents in the holdfast of three brown algae of the genus Laminaria were determined to compare with those in frond and stipe. The wild and cultivated kelps of Laminaria japonica , L. ochotensis , and L. diabolica were used as samples. The K content was markedly high (11.76–14.91 g/100 g dry weight) in the holdfast of cultivated L. japonica; the K/Na ratio (3.88–5.18) of the holdfast was greater than those of frond and stipe as well as the reported values of frond (1.0–2.2). The content of Ca in the holdfasts of these three species was also higher than those in frond and stipe. The content of Mn showed the same tendency. This is the first report showing that the holdfast of L. japonica and L. diabolica is rich in minerals, especially K.     

Transmission of Rhus (Rhus javanica L.) Yellows by Hishimonus sellatus and Host Range of the Causal Phytoplasma

In 1998, rhus (Rhus javanica L.) yellows (RhY), caused by phytoplasma, was found in Miyagi Prefecture, Japan. In vector transmission tests, Hishimonus sellatus acquired RhY phytoplasma from diseased R. javanica and transmitted it to healthy R. javanica. Twenty-two species of herbaceous plants in 10 families were infected with RhY phytoplasma by H. sellatus. The host range and main symptoms on test plants of RhY phytoplasma differed from those of Macrosteles striifrons-transmitted phytoplasmas, which belong to the same 16Sr I group phytoplasma. Received 6 December 1999/ Accepted in revised form 14 May 2000     

烟草普通花叶病毒在烟草胞质体中的增殖

 本试验证明了TMV-RNA在有细胞核的烟草原生质体中能大量增殖,但在无核的胞质体中却难以增殖。     

Complementary process to response bias in the centromedian nucleus of the thalamus

Activity in several areas of the human brain and the monkey brain increases when a subject anticipates events associated with a reward, implicating a role for bias of decision and action. However, in real life, events do not always appear as expected, and we must choose an undesirable action. More than half of the neurons in the monkey centromedian (CM) thalamus were selectively activated when a small-reward action was required but a large-reward option was anticipated. Electrical stimulation of the CM after a large-reward action request substituted a brisk performance with a sluggish performance. These results suggest involvement of the CM in a mechanism complementary to decision and action bias.