The Immunomodulating Effect of Phlorotannins from a Brown Alga,Eisenia nipponica,on Mice Stimulated with Ovalbumin through T Cell Regulation

Plant Foods for Human Nutrition - The immunomodulating effect of phlorotannin was investigated in mice stimulated by ovalbumin. When analyzing the main components of phlorotannin concentrate (PTC)...     

Experiential relationship between the farming rate of riverside land and flood concentration time factor

In order to prove a reduction function concerning flood damage according to land use, we have to compare evaluation indices, such as flood concentration times. These can be derived from the calculation of the outflows from two basins where rainfall, geology, geographical conditions, etc. are the same and only the land use is different. However, it is very difficult to obtain comparable data from large basins under the above mentioned conditions. An elaborate observation for a long period is required to obtain such data. In this paper, we aim to establish a calculation process that offers consideration factors from a viewpoint that is different from a conventional research where elaborate observation is essential. Therefore, first we use easily obtainable data of many basins, such as the information on the Internet, or data from official documents or the like, which are difficult to deal with in hydrology. Then, we obtain several evaluation indices, which are coefficients close to the flood concentration times in this paper, on each basin in which various kinds of land uses are mixed. We then perform the statistical analysis with a land use ratio. In order to use various data on several basins, we evaluate the difference in the land use ratio in the basin by using of a length of a riverside instead of an area in the basin. Moreover, since a river-mouth is at the end of the riverside and a water stage observation point is not at the river-mouth, an error arises. Although there are several problems in accuracy as mentioned above, the evaluation of the reduction function concerning the flood damage according to land use will be feasible, automatically and efficiently, if the calculation process is established.     

Stimulatory effect of cold acclimation on skeletal muscle branched-chain α-keto acid dehydrogenase in rats

The effects of cold-acclimation (3 weeks at 4°C) on the actual activities of branched-chain α-keto acid dehydrogenase (BCKDH) and pyruvate dehydrogenase (PDH) complexes in the skeletal muscle and liver of normal 6-week-old rats were studied. The activities of BCKDH and PDH complexes were assayed using [1–¹⁴C] α-ketoisocaproate and [1-¹⁴C]pyruvate, respectively. Cold-acclimation markedly stimulated the activity of BCKDH, and slightly but significantly increased the activities of PDH and citrate synthase (CS) in the skeletal muscle, but did not alter PDH, BCKDH or CS activities in the liver. The increase in muscle BCKDH activity (control rats, 1.45 ± 0.54 mU/g wet wt; cold-acclimated rats, 2.54 ± 0.50 mU/g wet wt; 75% increase: P  = 0.001) was much greater than the increases in PDH activity (84 ± 16 mU/g wet wt and 111 ± 25 mU/g wet wt; 32% increase: P  = 0.020) or CS activities (27 ± 3 μmol/min per g wet wt and 31 ± 2 μmol/min per g wet wt; 14% increase: P  = 0.046). These results suggest that, unlike PDH, BCKDH is not directly associated with the mitochondrial oxidative activity of the skeletal muscle of cold-acclimated rats. This study provides the first evidence that BCKDH in skeletal muscle responds selectively to cold-acclimation.     

Photosynthetic acclimation to dynamic changes in environmental conditions associated with deciduous overstory phenology in Daphniphyllum humile, an evergreen understory shrub

Photoprotective responses during photosynthetic acclimation in Daphniphyllum humile Maxim, an evergreen understory shrub that grows in temperate deciduous forests, were examined in relation to changes in light availability and temperature caused by the seasonal dynamics of canopy leaf phenology. Gradual increases in irradiance in the understory from summer to autumn as overstory foliage senesced were accompanied by increased concentrations of xanthophyll cycle pigments (VAZ) in understory leaves. The chlorophyll (Chl) a/b ratio in understory leaves also increased from summer to autumn, reflecting the change in ratio of the light-harvesting antenna to the reaction center. However, low temperatures following overstory leaf fall reduced Rubisco activity. In contrast, the photosynthetic capactiy of leaves of D. humile growing at the forest border, which was higher in summer than that of leaves of understory plants, decreased in autumn. In autumn, Fv/Fm ratios decreased and concentrations of zeaxanthin (Z) and especially antheraxanthin (A) increased in leaves of both forest-border and understory plants. Although VAZ was twice as high in leaves of forest-border than of understory plants, NPQ was similar in both. We conclude that leaves of understory plants are able to acclimate to seasonal changes in light and temperature by varying their photosynthetic and photoprotective functions, thereby taking advantage of the favorable light conditions caused by overstory leaf fall.     

Effects of discharge level on the load of dissolved and particulate components of stream nitrogen and phosphorus from a small afforested watershed of Japanese cypress (<Emphasis Type="Italic">Chamaecyparis obtusa</Emphasis>)

The behavior of dissolved and particulate components of stream nitrogen (N) and phosphorus (P) were measured for 2 years in a small mountainous watershed covered primarily with a plantation forest of Japanese cypress (Chamaecyparis obtusa). The load of dissolved N and P bore a consistent relationship to discharge while the load of particulate N and P varied by up to two orders of magnitude at a given discharge level. Most N was exported in a dissolved form (DN) while most P was exported in a particulate form (PP), which bears similarity to loads from agricultural watersheds. Owing to the different behaviors of DN and PP, changes in the total nitrogen (TN) load were primarily attributed to variations in discharge unlike changes in the total phosphorus (TP) load. High flow conditions, resulting from heavy rainfall, displayed PP release significantly larger than expected. The TP load in high flow conditions was severely underestimated using a regression equation expressed as a function of discharge, which was based on the weekly sampling data biased toward low flow conditions. In addition, the TN load during peak discharges in heavy rain events was underestimated by the regression equation because of unpredictable increases in the particulate component. Our study shows that the particulate component ratio determines whether discharge can explain changes in load regardless of chemical species. The results suggest that plantation forests in rainy regions can be a diffuse source of particulate nutrients depending on soil surface conditions.     

Hamiltonian Monte Carlo method for estimating variance components

A Hamiltonian Monte Carlo algorithm is a Markov chain Monte Carlo method, and the method has a potential to improve estimating parameters effectively. Hamiltonian Monte Carlo is based on Hamiltonian dynamics, and it follows Hamilton's equations, which are expressed as two differential equations. In the sampling process of Hamiltonian Monte Carlo, a numerical integration method called leapfrog integration is used to approximately solve Hamilton's equations, and the integration is required to set the number of discrete time steps and the integration stepsize. These two parameters require some amount of tuning and calibration for effective sampling. In this study, we applied the Hamiltonian Monte Carlo method to animal breeding data and identified the optimal tunings of leapfrog integration for normal and inverse chi-square distributions. Then, using real pig data, we revealed the properties of the Hamiltonian Monte Carlo method with the optimal tuning by applying models including variance explained by pedigree information or genomic information. Compared with the Gibbs sampling method, the Hamiltonian Monte Carlo method had superior performance in both models. We have provided the source codes of this method written in the Fortran language at https://github.com/A-ARAKAWA/HMC .     

Ammonia Emissions from Anaerobically-digested Slurry and Chemical Fertilizer Applied to Flooded Forage Rice

Ammonia fluxes from application of anaerobically-digested slurry (ADS) and chemical fertilizer (CF) to flooded forage rice (Oryza sativa L.) in Japan were measured using a dynamic flow-through chamber method in lysimeters. The CF was applied at a rate of 300 N ha^?1 (three times) as ammoniacal-N fertilizer, and the ADS was applied to the lysimeters at total rates equivalent to 75, 100 and 150 kg N ha^?1, by broadcasting uniformly into the floodwater at three or six times (equal splits) between 17th June and 17th November, 2005. The emission fluxes for the first 2 days after application were very high from ADS, the highest values being 679 compared with a maximum of 156 mg N m^?2 d^?1 from CF. Most (61–93%) of the ammonia loss occurred during the first 5 days after each application of fertilizer. The total N loss as ammonia from ADS (29.6–51.7%) was much higher than from CF (12.2%). The highest fluxes were observed in August (2005) when air temperature was highest. More ammonia was lost from the ADS applied at the early stages (i.e. root taking, tiller stages) than at later stages (i.e. elongation, fruiting stages) of rice growth.     

Reaction of manganese peroxidase ofBjerkandera adusta with synthetic lignin in acetone solution

The reaction of manganese peroxidase (MnP) of the white-rot fungusBjerkandera adusta with synthetic lignin dehydrogenation polymer, DHP) in acetone medium was investigated. Gel-permeation chromatography of the DHP treated by MnP demonstrated depolymerization of syringyl DHP in the reaction mixture containing 70% acetone; moreover, concomitant repolymerization occurred to give highly polymerized products. Guaiacyl DHP was only repolymerized by MnP in the same acetone solution without giving degradation products. Addition of ascorbic acid to reaction mixtures containing acetone resulted in preferential depolymerization of syringyl DHP.Part of this report was presented at the meeting of Kansai Branch, Japan Society for Bioscience, Biotechnology, and Agrochemistry in Kagawa, October 1996