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Decomposition subsystems have an essential role in forest dynamics but few studies demonstrate the effect of microbial decay traits on seedling regeneration. In the present study, we focused on seedling regeneration on coarse woody material (CWM), which is an important regeneration site for forest tree species, and the effects of wood decay type according to fungal decay preference for wood structural components on seedling colonization. Effects of log properties including wood decay type and other environmental variables on seedling density were evaluated by ordination methods and generalized linear models. In total, 22 woody species were recorded as seedlings on Pinus densiflora logs. By ordination analysis, white rot in heartwood and brown rot in sapwood, as well as canopy openness and log diameter, showed significant association with seedling communities. The factors selected for a generalized linear model for explaining seedling densities of the two dominant seedling species Cryptomeria japonica and P. densiflora included brown rot in sapwood and white rot in heartwood, but the effects were different: a positive effect of brown rot on C. japonica and a negative effect of white rot on P. densiflora. These results suggested that wood decay type could induce niche separation between dominant tree species regenerating on CWM. Key words: forest regeneration, log, rot type, seedling colonization, wood decay fungi. Les sous-systemes de decomposition jouent un role essentiel dans la dynamique forestiere mais peu d'etudes demontrent l'effet des caracteristiques de la decomposition microbienne sur la regeneration des semis. Dans cette etude, nous mettons l'accent sur la regeneration des semis sur le materiel ligneux grossier (MLG), qui constitue un important site de regeneration pour les especes forestieres arbustives, et sur les effets du type de carie dubois, d'apres les preferences des champignons de carie pour les composantes structurales du bois, sur la colonisation des semis. Les effets des proprietes des billes, incluant le type de carie, et des autres variables environnementales sur la densite des semis ont ete evalues avec des methodes d'ordination et des modeles lineaires generalises. Au total, les semis de 22 especes ligneuses ont ete trouves sur les billes du Pinus densiflora. Selon l'analyse par ordination, la carie blanche dans le bois de creur et la carie brune dans le bois d'aubier ainsi que l'ouverture du couvert forestier et le diametre des billes etaient significativement associes a des communautes de semis. Les facteurs retenus pour construire un modele lineaire generalise en vue d'expliquer la densite des semis des deux especes dominantes de semis, soit Cryptomeria japonica et P. densiflora, incluaient la carie brune dans lebois d'aubier et la carie blanche dans lebois de creur mais leur effet etait different: la carie brune avait un effet positif sur C. japonica et la carie blanche avait un effet negatif sur P. densiflora. Ces resultats indiquent que le type de carie du bois pourrait provoquer une differenciation des niches parmi les especes d'arbres dominantes qui se regenerent sur les MLG. [Traduit par la Redaction] Mots-cles: regeneration de la foret, bille, type de carie, colonisation des semis, champignons responsables de la carie du bois., 1. Introduction Environmental heterogeneity created by ecosystem engineers has large impacts on biotic communities and the ecosystem processes (Odling-Smee et al. 2003). Microbes of the decomposition subsystems such as fungi [...]

A three-dimensional numerical analysis conducted on the characteristics of electromagnetic force in the mixed-micro levitation system is presented. The study includes the results of comparisons of the numerical analysis with the experimental data. The results confirmed the three-dimensional structure of magnetic fields and the strong influence of the electromagnetic performance of the superconductors on the attributes of the electromagnetic force acting on the iron.

Aims: Secretory phospholipase A2 is associated with ischaemic injury in the human heart, but the distribution of type V secretory phospholipase A2 (sPLA2-V) remains unknown. The significance of sPLA2-V in myocardial infarction was investigated histopathologically. Methods: Sequential changes in the localization of sPLA2-V and its mRNA in myocardial tissues obtained from 30 autopsied hearts were examined by immunohistochemistry and in situ hybridization and compared with those of fibronectin, vascular endothelial growth factor (VEGF), interleukin (IL)-1 β, tumour necrosis factor (TNF)-α, and cyclooxygenase-2 (COX-2). Results: No expression of sPLA2-V was observed in normal heart, but it was promptly expressed in wavy myofibres positive for fibronectin just after the onset of infarction. sPLA2-V was subsequently expressed in ischaemic cardiomyocytes around the lesion. The expression decreased at the granulation tissue and disappeared at the chronic stage with scar formation. The distribution of the signal for sPLA2-V mRNA paralleled that of the protein. Ischaemic myocytes around the lesion expressed VEGP, IL-1 β, TNF-α and COX-2 at all stages. Conclusions: sPLA2-V production in myocardium is limited to the acute phase of infarction. sPLA2-V may play a dual role, acting both to remove degraded cell-membrane through cooperative activity with COX-2 in necrotic areas and to attack ischaemic myocytes around the lesion via degradation of membrane phospholipids. [ABSTRACT FROM AUTHOR]

Recent studies using rabbit antisera to the separated HLA-DR α and β subunits have suggested that α chain-specific, but not β chain-specific, antisera inhibit T cell proliferative responses in primary and secondary human autologous mixed lymphocyte reaction (AMLR). In the present study, with the aid of sequential co-precipitation assays and Western blotting methods, a monoclonal rat alloantibody 1E4, specific for the β chain of rat class II molecules carrying an Ia determinant Ba-2.7, was characterized to recognize a monomorphic determinant located on the β chain of DR antigens. This antibody and a murine monoclonal antibody HU-4, also specific for the β chain of DR antigens, strongly inhibited both primary and secondary AMLR through a mechanism distinct from an antibody-dependent cell-mediated cytotoxicity reaction. These results indicate that the inhibition of AMLR is not a unique feature of DR α-specific antibodies. [ABSTRACT FROM AUTHOR]