Method to estimate the internal stresses due to moisture in wood using transmission properties of microwaves     

Tomio?TakemuraEmail author  Takashi?Taniguchi 《Journal of Wood Science》2004,50(1):15-21

The purpose of this paper is to offer a new method for detecting stress in wood due to moisture along the lines of a theory reported previously. According to the theory, the stress in wood could be estimated from the moisture content of the wood and the power voltage of a microwave moisture meter (i.e., attenuation of the projected microwave). This seems to suggest a possibility of utilizing microwaves in the field of stress detection. To develop such an idea, the stress formulas were initially modified to the form of an uni-variable function of power voltage, and the application method of the formulas to detection was tried. Finally, these results were applied to the data of sugi (Cryptomeria japonica) lumber in the previous experiment. The estimated strains showed fairly good agreement with those observed. It could be concluded from this study that the proposed method might be available for detecting stress in wood due to moisture.Part of this report was presented at the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, April 2002  相似文献   

Can spines deter deer browsing?: a field experiment using a shrub <Emphasis Type="Italic">Damnacanthus indicus</Emphasis>     

Mayura?TakadaEmail author  Masahiko?Asada  Tadashi?Miyashita 《Journal of Forest Research》2003,8(4):321-323

We examined the defensive function of spines of Damnacanthus indicus against deer herbivory by experimentally removing spines in the field where deer density is high. Individuals of D. indicus whose spines had been removed had a higher probability of being browsed by deer than control individuals. In addition, plant height was significantly lower for individuals that were browsed than those that were not. These results support the notion that spines of D. indicus have a function to deter deer browsing. This study is the first to demonstrate experimentally the defensive function of spines against large mammals in temperate areas.  相似文献   

Effect of organic matier application and water regimes on the transformation of fertilizer nitrogen in a Philippine soil     

Tomio Yoshida  Benjamin C. Padre Jr. 《Soil Science and Plant Nutrition》2013,59(3):281-292

Greenhouse experiments using the tracer technique showed that about 20 per cent of the fertilizer nitrogen added as basal to the Maahas clay soil wa11 immobilized in submerged soils to which no organic material was added. The addition of organic matter to the soil increases the amount of nitrogen immobilized and the magnitude depends on the carbon to nitrogen ratio of the materials added. More fertilizer nitrogen waa immobilized in the soils under upland and alternate wet-and-dry conditions than under submerged soil conditions.

The uptake of fertilizer nitrogen by rice plants growing under submerged soil conditions ceased at the vegetative stage of growth because only a small amou11t of available nitrogen remains in the soil at this time, but the rice plant continued to absorb gradually untagged nitrogen from the soil throughout the reproductive etages of growth.

Losses of fertilizer nitrogen were great under the alternate wet-and-dry conditions (submerged-upland). The loss of nitrogen from the soli-plant system was reduced by the addition of dee straw, which also reduced the uptake of fertilizer nitrogen but not the total dry matter production under the experimental conditions. Fertilizer nitrogen immobilized during the first crop remained mostly in the soil throughout the full period of the second crop.

The total nitrogen uptake by rice plants was not affected by the soil moisture tension under the upland conaltlons used in the study but the movement of nitrogen from the leaves to the panicles during the reproductive etage seemed to decrease as the soil moisture tension increased.  相似文献   

A method for the microinjection into naturally spawned eggs of marine fish,especially cultured Pacific bluefin tuna <Emphasis Type="Italic">Thunnus orientalis</Emphasis>     

Satoshi Otani  Manabu Ohara  Shigeru Miyashita  Toru Kobayashi 《Fisheries Science》2008,74(1):208-210

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Critical swimming speed and maximum sustainable swimming speed of juvenile Pacific bluefin tuna, Thunnus orientalis     

F. de la S. Sabate  Y. Nakagawa  T. Nasu  W. Sakamoto  S. Miyashita 《Aquaculture International》2013,21(1):177-181

Tank wall collision is one of the major causes of mortality during the early-stage rearing of Pacific bluefin tuna, Thunnus orientalis (PBT). Therefore, to design a rearing environment that meets the needs of juvenile PBT, it is important to gather information about their swimming capabilities. We conducted experiments to examine the relative critical swimming speed (RCSS) and maximum sustainable swimming speed (MSSS) of early-stage PBT. The fish were kept in 3-tonne tanks and fed on artificial pellets every 2 h from dusk to dawn. We conducted two sets of experiments to measure swimming speed; the fish were introduced one at a time into a water funnel, and the water current velocity was gradually increased over time to estimate RCSS, or the water current was kept at a constant velocity to estimate MSSS. We measured the RCSS of 72 PBT juveniles (24–29 days after hatching (DAH); standard length (SL), 15.0 ± 2.3 mm) and the MSSS of 32 PBT juveniles (28–37 DAH; SL, 20.0 ± 5.1 mm) in the laboratory. The RCSS ranged from 4.7 to 20.3 SL/s (average, 12.4 ± 3.3 SL/s), and the MSSS was estimated to be approximately 4 SL/s. We speculate that introducing a water current in the rearing tank of no more than 4 SL/s could positively affect the survival of juvenile PBT.  相似文献   

Habitat and prey selection of common minke,sei, and Bryde’s whales in mesoscale during summer in the subarctic and transition regions of the western North Pacific     

Hikaru Watanabe  Makoto Okazaki  Tsutomu Tamura  Kenji Konishi  Denzo Inagake  Takeharu Bando  Hiroshi Kiwada  Tomio Miyashita 《Fisheries Science》2012,78(3):557-567

This study represents the first quantitative analysis of the characteristics of the distribution areas and stomach contents of common minke whale Balaenoptera acutorostrata, sei whale B. borealis, and Bryde’s whale B. edeni in relation to oceanographic and prey environments in mid summer in the western North Pacific. Common minke whales were distributed within subarctic regions and the northernmost region of the transitional domain, coinciding with the main habitat of their preferred prey, Pacific saury Cololabis saira. Sei whales were mainly found in the northernmost part of the transition zone and showed prey preference for Japanese anchovy Engraulis japonica, which was significantly more abundant in the main distribution area of the whale than in its adjacent areas. “Hot spots” of Bryde’s whales were found in several regions of the transition zone between the subarctic boundary and the Kuroshio front. This whale species preferred Japanese anchovy as prey, for which the distribution density was significantly higher in the main distribution area of the whale than in the adjacent areas. These results indicate that the summer distributions of Pacific saury and Japanese anchovy greatly influence the distributions of these whale species, suggesting that the whales’ habitat selection is closely related to their prey selection.  相似文献   

Flow field control via aeration adjustment for the enhancement of larval survival of the kelp grouper Epinephelus bruneus (Perciformes:Serranidae)     

Ching Fui Fui  Akira Miura  Yoshizumi Nakagawa  Keitaro Kato  Shigeharu Senoo  Wataru Sakamoto  Kenji Takii  Shigeru Miyashita 《Aquaculture Research》2014,45(5):874-881

Flow field control via aeration adjustment for the enhancement of larval survival of the kelp grouper Epinephelus bruneus was examined. Aeration rate of 300 mL min^?1 was introduced during daylight (07:00–19:00 hours) and adjusted to 0, 300 and 900 mL min^?1 at night (19:00–07:00 hours). Larval sinking velocity±SD increased from 0.08 ± 0.05 to 0.26 ± 0.24 cm sec^?1 from 4 to 12 days after hatching (DAH), indicating their susceptibility to sink. Larvae reared in 300 mLmin^?1 attained the highest survival rate at 24.9 ± 3.4%, but remained significantly smaller in growth: 4.54 ± 0.56 mm compared with 4.82 ± 0.53 mm in 900 mL min^?1. The flow field in 300 and 900 mL min^?1 was at 10–20 and 15–25 cm above the bottom of the tank and 8.0 and 1.0 cm beneath the water surface. A favourable rearing condition was observed in 300 mL min^?1 as larvae were away from the bottom and surface areas, thus preventing them from dying due to sinking and surface tension‐related death (STRD). Although sinking death was decreased with an increasing aeration rate, the stronger flow had increased larval susceptibility to STRD. Our findings suggest that aeration at 300 mL min^?1 could enhance larval survival by reducing both sinking death and STRD.  相似文献   

Aeration rate adjustment at night to prevent sinking syndrome‐related death in the tiger grouper Epinephelus fuscoguttatus (Perciformes:Serranidae) larvae          下载免费PDF全文

Ching Fui Fui  Akira Miura  Yoshizumi Nakagawa  Keitaro Kato  Wataru Sakamoto  Kenji Takii  Shigeru Miyashita  Shigeharu Senoo 《Aquaculture Research》2016,47(1):165-175

The effects of different aeration rates at night to prevent sinking syndrome‐related death (SSRD) of the tiger grouper, Epinephelus fuscoguttatus were examined. The aeration rates were fixed at 300 mL min^?1 at daytime (07:00–19:00 hours) and regulated to 0, 300 and 900 mL min^?1 at night (19:00–07:00 hours). Larval survival, growth, feeding intake, sinking velocity, distribution and behaviour, stress level, surface tension‐related death (STRD) and flow velocity distribution were assessed. The occurrence of SSRD in the tiger grouper was observed through the accelerated sinking velocity (Vl) (from 0.15 ± 0.09 cm s^?1 at 4 days AH to 0.41 ± 0.09 cm s^?1 at 12 days AH) coupled with larval passive swimming behaviour at night‐time. On the final day of experiment (15 days AH), larvae reared in 900 mL min^?1 at night had attained significantly higher (P < 0.05) survival (34.4 ± 5.5%), growth (5.8 ± 0.5 mm) and feeding intake (60.46 ± 6.98 ind. larva^?1). A favourable flow field for the tiger grouper was produced in 900 mL min^?1 at night‐time, in which larvae were transported 15–25 cm above the tank bottom and 1.0 cm beneath the water surface. Under these night‐time rearing conditions, larval stress level and number of STRD reared in 900 mL min^?1 compared with those observed in 300 mL min^?1 remained insignificant, indicating that strong turbulence of flow velocity was not detrimental for larvae. Our findings recommend aeration at 900 mL min^?1 at night as this could improve larval survival by reducing SSRD.  相似文献   

Chemical Characteristics of Fog Water at Mt. Tateyama, Near the Coast of the Japan Sea in Central Japan     

Koichi Watanabe  Hideharu Honoki  Ayumi Iwai  Atsushi Tomatsu  Kiyoshi Noritake  Nobuko Miyashita  Keiko Yamada  Hirotsugu Yamada  Hideki Kawamura  Kazuma Aoki 《Water, air, and soil pollution》2010,211(1-4):379-393

Measurements of the chemical composition of fog water at Murododaira (altitude, 2,450 m), on the western slope of Mt. Tateyama near the coast of the Japan Sea, were performed each autumn from 2004 through 2007. Strong acidic fogs (pH?<?4) containing high concentrations of nssSO ₄ ^2? were frequently observed in the autumn of 2005, when the air mass at Mt. Tateyama originated mainly from the polluted regions of Asia. The ratio of NO ₃ ^? /nssSO ₄ ^2? in fog water was relatively high in 2004 and 2007. High concentrations of nssCa²⁺ derived from dust particles were detected in 2006. Background Kosa particles might have been predominant in the free troposphere and could have neutralized acidic fogs in the autumn of 2006. High concentrations of sea-salt components were also observed in October 2005. The sea-salt particles might have been transported from the Pacific Ocean by a strong typhoon, and significant Mg²⁺ loss was observed. Peroxides higher than 100 μM, which are seriously harmful to vegetation were sometimes detected.  相似文献   

Dietary combination of fucoxanthin and fish oil attenuates the weight gain of white adipose tissue and decreases blood glucose in obese/diabetic KK-Ay mice     

Maeda H  Hosokawa M  Sashima T  Miyashita K 《Journal of agricultural and food chemistry》2007,55(19):7701-7706

Fucoxanthin is a marine carotenoid found in edible brown seaweeds. We previously reported that dietary fucoxanthin attenuates the weight gain of white adipose tissue (WAT) of diabetic/obese KK- A(y) mice. In this study, to evaluate the antiobesity and antidiabetic effects of fucoxanthin and fish oil, we investigated the effect on the WAT weight, blood glucose, and insulin levels of KK- A(y) mice. Furthermore, the expression level of uncoupling protein 1 (UCP1) and adipokine mRNA in WAT were measured. After 4 weeks of feeding, 0.2% fucoxanthin in the diet markedly attenuated the gain of WAT weight in KK- A(y) mice with increasing UCP1 expression compared with the control mice. The WAT weight of the mice fed 0.1% fucoxanthin and 6.9% fish oil was also significantly lower than that of the mice fed fucoxanthin alone. In addition, 0.2% fucoxanthin markedly decreased the blood glucose and plasma insulin concentrations in KK- A(y) mice. The mice fed with the combination diet of 0.1% fucoxanthin and fish oil also showed improvements similar to that of 0.2% fucoxanthin. Leptin and tumor necrosis factor (TNFalpha) mRNA expression in WAT were significantly down-regulated by 0.2% fucoxanthin. These results suggest that dietary fucoxanthin decreases the blood glucose and plasma insulin concentration of KK- A(y) along with down-regulating TNFalpha mRNA. In addition, the combination of fucoxanthin and fish oil is more effective for attenuating the weight gain of WAT than feeding with fucoxanthin alone.  相似文献