Prebiotic effect of glycerol galactoside isolated from color-faded nori in rats

Glycerol galactoside (GG; floridoside: 2-O-glycerol-α-d-galactopyranoside, and isofloridoside: 1-O-glycerol-α-d-galactopyranoside) is known to be a component of edible red seaweed nori. Recently, we have found that low-quality nori (color-faded nori), which has a low protein content, contains a large quantity of GG. From further studies, we have also found that GG has prebiotic characteristics in vitro. In this study, we evaluated the in vivo prebiotic activity of GG in rats. Dietary GG selectively increased the cecal Bifidobacterium count in rats. Other indices of prebiotics, such as pH of cecal content, organic acid concentrations, and fecal weight, also supported the existence of prebiotic activity of GG. The present data will also contribute to the development of a new method of utilizing color-faded nori as a health-promoting foodstuff.     

Evaluation of rolling shear strength of plywood by flexural vibration method

The rolling shear strength of plywood was evaluated using a flexural vibration test. Test specimens were lauan and Douglas fir three-ply plywoods made from thick veneers. The dynamic shear and Young's moduli were determined using the flexural vibration method, which involved in-plane and out-of-plane flexural vibration. The rolling shear strength was determined using the static destructive method, which is dependent on the direction of the lathe check in the core veneer. Before and after accelerated aging treatments were conducted, there were relations between out-of-plane dynamic properties (out-of-plane shear and Young's moduli) and its rolling shear strength. It was concluded that the rolling shear strength is related not only to the shear property of the core but the flexural stiffness of two faces when the deformation of out-of-plane plywood was not restrained.Part of this work was presented at the 47th Annual Meeting of The Japan Wood Research Society, Kochi, April 1997     

Phenotypic characterization and cultivation conditions of inhibitor-producing fungus isolated from marine sediment

ABSTRACT:   Tyrosinase inhibitor-producing fungus of Trichoderma sp. strain H1-7, which was isolated from marine sediment, was investigated by phylogenetic analysis and physiological characteristics. Phylogenetic analyses of the strain were similar to Trichoderma atroviride or T. viride . Physiological characteristics of the strain were similar to T. viride , and based on these results, it was identified as T. viride . Characterization of tyrosinase inhibitory activity of a culture supernatant of the strain was investigated. The inhibitory activity of the supernatant of the strain decreased after cultivation for more than 3 days. Furthermore, sea water was not essential for the production of the tyrosinase inhibitor (TI). When TI production of the strain was compared to T. viride , the strain showed higher activity than T. viride . From this result, it seemed that the strain had characteristic features comparable to T. viride , which was isolated from the terrestrial environment. As TI production of the strain showed higher potential than that of T. viride , it is necessary to elucidate the chemical structure of TI exemplified in the present study.     

Factors influencing steel tool wear when milling wood

The wear of high speed steel cutting tools after milling wood of four selected wood species was studied. For the experiments wood specimens were chosen with very different silica contamination, wood density, and high temperature corrosivity (HTC) of wood towards tool material. Analyses performed show that the silica content and wood density display poor linear correlation with the cutting tools wear, while the correlation of the HTC appeared very good. The silica contamination and the HTC effects overshadow each other. Thus, a theoretical multivariable simulation of the cutting edge wearing process, employing all experimental variables, was applied, providing a very good explanation of the analyzed problem.     

Performance of coated carbide tools in turning wood-based materials: Effect of cutting speeds and coating materials on the wear characteristics of coated carbide tools in turning wood-chip cement board

This paper reports on the performance of coated carbide tools in turning wood-chip cement board. The coating materials studied were titanium carbonitride (TiCN), titanium nitride (TiN), chromium nitride (CrN), and titanium nitride/aluminum nitride (TiN/AlN), which were synthesized on the P30 carbide substrate. The aim is to investigate the effect of coating materials and cutting speeds on the wear characteristics of the coated carbide tools. Cutting tests were performed when turning wood-chip cement board at cutting speeds of 30, 40, 50 and 60 m/s, a depth of cut of 1mm, and a feed of 0.05 mm/rev. The results of the study show that the coated carbide tools provided better performance than the P30 carbide tool, especially in terms of reducing the progression of the wear rate and clearance wear. The TiN/AlN-coated carbide tool showed the smallest increase in both wear rate and clearance wear with an increase in cutting speed and had the longest tool life among the coated carbide tools investigated. Though the TiCN-coated carbide tool was observed to have a low wear rate and low clearance wear for cutting speeds of 30 and 40m/s, when the cutting speeds were >50m/s its wear rate and clearance wear were almost the same as those of CrN-and TiN-coated carbide tools, which had high values for these parameters.Part of this paper was presented at the 21st IUFRO World Congress, August 2000, Kuala Lumpur, Malaysia     

The critical rotational speed of circular saw: simple measurement method and its practical implementations

Operation safety during sawing operations as well as dimensional accuracy and surface roughness depend on circular saw dynamic features among other factors such as circular saw blade accuracy and static/dynamic properties of the machine tool. Manufacturers of saw blades have an obligation to mark tools with a value stating the maximum allowed rotational speed for each saw. However, in some cases the value indicated on the saw corresponds to the critical rotational speed or is dangerously close to this critical value. Saw operation at the critical rotational speed is inadvisable and may result in serious injury or depreciation of product quality. This report outlines a simple methodology for evaluation of circular saw critical rotational speed. The assessment was conducted with a camera vision technique on the basis of an impulse test. Results are compared with theoretically calculated critical rotational speeds and the marks on saw blades.     

Evaluation of surface smoothness using a light-sectioning shadow scanner

A new type of sensor for rapid three-dimensional evaluation of surface geometrical properties is presented. Light emitted with a fixed small angle to the surface plane by a projector is directed into the measured surface. A curtain installed in the light path close to the surface creates a shadow on the measured surface. The shape of the border between bright (highly lit area) and dark (shadow area) is a profile section of the surface. The camera installed over the measured surface captures an image of the border and a digital signal processor using image analysis techniques digitizes the profile section. The shadow scanner method evaluated here could be used for rapid and accurate scans of surfaces of various porous materials, particularly wood, veneer, paper, fiberboards, leaves, and similar materials in both laboratory and industrial applications. The simplicity of the sensor is an advantage because it makes the system easy to maintain, resistant to breakage, and inexpensive. Its straightforward nature and high accuracy enables the method to be utilized for on-line measurement, and therefore it is suitable for industrial application.     

Effect of combinations of wood and counterface materials on three-body abrasive wear

The abrasion characteristics of various combinations of wood and counterface materials in three-body abrasive wear were investigated. Various wood samples were examined in combination with wood, plastic, and metal counterface materials. The wear coefficient in the wood samples was calculated as the wear volume of the friction surface divided by the sliding distance and the applied load. The results showed that the wear coefficient was smaller in cases where the wood samples had greater yield stress. The wear coefficient increased as the yield stress of the various counterface materials increased, reaching a maximum value and then decreased as the yield stress increased. This result indicated that a peak value existed for the wear coefficient in combination with the counterface material.Part of this report was presented at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001     

Genetic characterization and susceptibility on poultry and mammal of H7N6 subtype avian influenza virus isolated in Japan in 2009

From February to March 2009, six strains of H7N6 subtype avian influenza virus were isolated from quails in three farms in Aichi prefecture in Japan. The isolates were shown to be low pathogenic for chicken by the examination performed using the "Manual of Standards for Diagnostic Tests and Vaccines" by World organisation for Animal Health (OIE). The deduced amino acid sequence at the cleavage site was PE (I/Q/L) PKRR (nucleotide sequences were cct gaa (a/c) (t/a) a cc (a/g) aaa aga aga), suggesting persistence in domestic poultry for some time. The direct putative ancestor strain could not be elucidated by phylogenetic analysis of all genome segments of the quail isolates. Diverged date from a putative common ancestor in a non-rooted phylogenetic tree among quail viruses was estimated between March 2002 and July 2004. Three putative N-linked glycosylation sites resided in the vicinity of the receptor binding pocket of HA1 region. They are considered to decrease the reactivity of neutralizing antibody against the virus. Experiments for the infectivity and pathogenicity of a quail strain to poultry indicated that the quail isolate had higher infectivity to quails than chickens and ducks. Direct and dust-borne and/or droplet-borne transmissions among quail were proven in quails with and without direct contact with experimentally infected quails. The virus is seldom transmitted among chickens either directly or indirectly, and indirect transmission from infected quails to chickens was not observed. The pathogenicity of the quail strain for mammalian, pig and mouse was low, although it could replicate in those animals.     

Comparison of cadherin and integrin localization in bovine cystic and healthy follicles

As stage progresses in the cystic follicle, granulosa cells are lost. We hypothesized that the granulosa and theca interna layers are detached in association with weakened expression of cell adhesion molecules such as cadherin (cell–cell adhesion) and integrin (cell–extracellular matrix adhesion) in cystic follicles. To elucidate this hypothesis, we immunolocalized these molecules in the granulosa and theca interna and compared them between cystic and small healthy follicles. Sections were immunostained with cadherin and integrin β₁ antibodies and their localizations were compared. Cadherin‐positive reaction was seen in the cytoplasma of all granulosa cells. No increase in the frequency of cadherin‐positive area in the granulosa layers and the intensity of cadherin immunoreaction in the theca interna was detected in cystic follicles compared with healthy ones. A dense immunoreaction product of integrin β₁ was detected in the theca interna in both cystic and healthy follicles. Intensity of integrin β₁‐immuno reaction in the granulosa layers and integrin β₁‐positive area in the theca interna was significantly lower in the cystic follicle than in the healthy follicles. These results suggest that granulosa and theca interna cells are detached while maintaining the cell–cell adhesion, resulting in the consequent loss of these layers from the cystic follicle.