Continuum contraction of tension wood fiber induced by repetitive hygrothermal treatment

Wood Science and Technology - Tension wood, when kiln-dried, is likely to deform hugely, which is probably caused by a gelatinous layer of the gelatinous fiber. To elucidate the mechanism behind...     

Nutrient starvation affects expression of LC3 family at the feto-maternal interface during murine placentation

LC3 − the mammalian homolog of Atg8 − was found as autophagosome membrane binding protein in mammals and widely used as an autophagosomal marker. LC3A, B and C show different expression patterns in each tissue. The aim of this study was to reveal the differences of expression patterns among LC3 families in mouse placenta under normal condition and nutrient starving condition. LC3A and B were highly expressed in decidual cells. LC3A and B were increased in D14 compared with D12 and D16 in mouse placenta, while LC3C was decreased. Starvation induced increase in LC3B expression specifically. Immunohistochemistry showed different expression patterns among LC3A, B and C. LC3A expression in syncytiotrophoblast was vanished by starvation. The results of real time RT-PCR suggested differences between D12 and D16 in autophagic cascade induced by starvation. Taken together, this study suggests that autophagy could play a role in placental invasion system and that nutrient starvation affects LC3B expression.     

Comparison of environmental conditions in two representative oyster farming areas: Hiroshima Bay,western Japan and Oginoham a Bay (a branch of Ishinomaki Bay), northern Japan

ABSTRACT:   Sea water environmental conditions over annual cycles were investigated and compared between two oyster farming areas, western Hiroshima Bay and Oginohama Bay (a branch of Ishinomaki Bay) in Miyagi Prefecture, to appropriately manage oyster culture or more efficiently utilize farming areas. The environmental parameters of temperature, salinity, nutrient concentrations (NO₂–N, NO₃–N, NH₄–N, PO₄–P, and SiO₂–Si) and size-fractionated chlorophyll- a (<0.2, 2–20, >20µm), and abundances of microzooplankton were measured in each bay at the surface, and 2 and 5 m depth layers. Differences in the annual mean values and results with monthly paired Student's t -tests showed that salinity was lower, and temperature, nutrient (especially PO₄–P) and chlorophyll- a concentrations, and abundance of microzooplankton, were higher in Hiroshima Bay than in Oginohama Bay. Differences in environmental conditions between inshore and offshore areas of each bay suggest that inflows of river water in western Hiroshima Bay and sea water from offshore had the most significant effects on the environmental conditions. It is concluded that such oceanographic and biological differences strongly affect the oyster farming system, especially regarding the optimum usage of offshore areas in Summer under clean, cold and stable seawater conditions, rather than food quantity in Hiroshima Bay, and under more abundant food conditions in Oginohama Bay.     

A size-structured model for a stock-recovery program for an exploited endemic fisheries resource

The size of harvests temporarily decreases following stock-recovery programs for overexploited resources. The process of stock recovery is quite uncertain, because of unknown life-history parameters, changes in environmental conditions, and human impact. To project future stock recovery, we considered a size-structured matrix model of a stock-recovery program, in which the minimum body size in the first harvest is increased. We applied some common concepts, including yield per recruitment, spawning per recruitment, and reproductive value, to a size-structured matrix model that incorporated economic discounting. The size-structured model predicted the following characteristics in stock-recovery processes: several years must pass for the harvest to increase, and the time-lag between the inception of the management program and the increase in the catch is caused by intergenerational momentum in demography. We also investigated the effects on the recovery process of temporal environmental fluctuations. We applied our model to a stock-recovery program of the corbiculid Seta clam (Corbicula sandai) in Lake Biwa, Japan.     

Deformation induced by ethanol substitution in normal and tension wood of chestnut (Castanea sativa Mill.) and simarouba (Simarouba amara Aubl.)

Wood deformation in the longitudinal and tangential directions induced by ethanol substitution and oven-drying was measured in normal wood (NW) and tension wood (TW) of chestnut (Castanea sativa Mill.) (TW with G-fibres) and simarouba (Simarouba amara Aubl.) (TW without G-fibres). The results show that with increased concentration of ethanol solution TW tends to contract, regardless of the presence or absence of G-fibres. In contrast, both NW and opposite wood expand at different rates in the longitudinal direction. These results are discussed and explained by the role of stress state at cell wall level.     

Regulation of muscular glutamate metabolism by high‐protein diet in broiler chicks

The major taste active component, glutamate (Glu), improves the taste of meat. In this study, we investigated the effect of a short‐term high‐protein (HCP) diet on the intramuscular free Glu content to improve the taste of meat. Furthermore, we elucidated how the muscle free Glu content was controlled by the HCP diet. Chicks (14 days old) were fed the control diet or HCP diet for 10 days. Plasma and muscle free amino acid concentrations, and activity and messenger RNA (mRNA) expression of muscle enzymes related to Glu metabolism were determined. Muscle free Glu content was increased (P < 0.01) by 51%. Activity and mRNA expression of glutaminase (GA), which is one of the major Glu‐related enzymes, were significantly decreased (P < 0.05) in the HCP group because of feedback inhibition. The mRNA expression of lysine α‐ketoglutarate reductase (LKR), which is the enzyme involved in lysine (Lys) degradation and Glu production, was significantly increased (P < 0.001) in the HCP group. These results suggest that short‐term dietary HCP feeding is an effective treatment for improving the taste of meat. Furthermore, our results suggest that the free Glu content in muscle is regulated by GA and LKR.