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501.
We investigated a method for measuring the refining degree of bamboo charcoal using an alternating current. The bamboo charcoal
was made under heating conditions of 400°–900°C (set temperature) and 0—3 h (holding time at each set temperature). The qualities
of the bamboo charcoal could not be estimated from the yield, and electric tests were required. The effect of the variation
in sample thickness on the impedance could be ignored. Attaching two plate electrodes to the same surface of a specimen enabled
high accuracy and practical use. The impedance was found to be a suitable index for estimating the refining degree of the
bamboo charcoal, such as the specific electric resistance. We believe that bamboo changes from an insulator to a conductor
suddenly when processed at 600°–750°C for 0–2 h. It is possible that the integral of temperature with time in a specimen during
heating is useful for approximately estimating impedance. 相似文献
502.
Growth of regenerating trees in different light environments was studied for the mountainous, mixed-species forests in the Carpathian Mountains of Romania. The primary species in these mixtures were silver fir (Abies alba Mill.), European beech (Fagus sylvatica L.) and Norway spruce (Picea abies (L.) Karst). Seedlings/saplings of these species were selected and measured in different stands from two different geographical locations. Regenerating trees were measured for height and diameter growth during the summer of 2002. For each seedling/sapling, percentage of above canopy light (PACL) and stand basal area (BA) were used to assess available and occupied growing space respectively. Regeneration growth was compared against these two variables and regression relationships were developed. Using these models, we predicted the dynamics of regeneration as both growth and species composition. Our results showed that in low-light environments (PACL<20–35%; BA>30 m2/ha), shade tolerant fir and beech clearly outcompeted the spruce. Therefore, in dense stands, spruce could be eliminated by the shade tolerant species. For intermediate levels of cover (PACL=35–70%; BA=15–35 m2/ha) the spruce grew at comparable rates as the beech and fir. All three species showed similar growth rates in open conditions (PACL>80–90%; BA<15–20 m2/ha) with the spruce having a tendency to outgrow the others. However, in terms of establishment, such conditions favor spruce and inhibit fir and beech. 相似文献
503.
Lack of exposed ice inside lunar south pole Shackleton Crater 总被引:2,自引:0,他引:2
Haruyama J Ohtake M Matsunaga T Morota T Honda C Yokota Y Pieters CM Hara S Hioki K Saiki K Miyamoto H Iwasaki A Abe M Ogawa Y Takeda H Shirao M Yamaji A Josset JL 《Science (New York, N.Y.)》2008,322(5903):938-939
The inside of Shackleton Crater at the lunar south pole is permanently shadowed; it has been inferred to hold water-ice deposits. The Terrain Camera (TC), a 10-meter-resolution stereo camera onboard the Selenological and Engineering Explorer (SELENE) spacecraft, succeeded in imaging the inside of the crater, which was faintly lit by sunlight scattered from the upper inner wall near the rim. The estimated temperature of the crater floor, based on the crater shape model derived from the TC data, is less than approximately 90 kelvin, cold enough to hold water-ice. However, at the TC's spatial resolution, the derived albedo indicates that exposed relatively pure water-ice deposits are not on the crater floor. Water-ice may be disseminated and mixed with soil over a small percentage of the area or may not exist at all. 相似文献
504.
Haruhisa Fukada Jon T. Dickey Andrew L. Pierce Nicholas Hodges Akihiko Hara Penny Swanson Walton W. Dickhoff 《Fish physiology and biochemistry》2003,28(1-4):335-336
The expression levels of growth hormone receptor (GHR) and insulin-like growth factor (IGF-I) in gonads of maturing coho salmon were measured by real-time PCR. The GHR and IGF-I mRNAs showed different gene expression pattern between male and female. These results suggest that a sexual dimorphism may exist in the GHR and IGF-I mRNA expressions of coho salmon during gonadal maturation 相似文献
505.
Takeshi Yamamoto Kazuhisa Teruya Takashi Hara Hiroto Hokazono Hiroshi Hashimoto Nobuhiro Suzuki Yasuro Iwashita Hiroyuki Matsunari Hirofumi Furuita Keiichi Mushiake 《Fisheries Science》2008,74(5):1096-1108
To improve the nutritional quality of live foods and dry feeds ordinarily used for the seed production of amberjack Seriola dumerili, the nutrient contents of rotifers, Artemia nauplii and commercial feeds used in two larval production stations were evaluated. For comparison of the nutrient contents,
artificially produced larvae, wild-caught juveniles and wild zooplankton samples were also analyzed. The proportions of 22∶6n-3
in the polar lipid of the cultured larvae increased by feeding the dry feeds. The taurine contents of the cultured larvae
reflected the contents of their foods (rotifers<dry feed<Artemia nauplii). The taurine content and the proportion of 22∶6n-3 in Acartia spp. were higher than in foods fed to the larvae. These parameters in the wild juveniles were higher than the cultured ones.
The A/E ratios [(each essential amino acid/total essential amino acids)×1000] of the total amino acids of the live foods and
dry feeds were similar to those of the cultured larvae, except for the lower ratios of histidine, arginine, threonine and
lysine in the live foods. The mucosal folds of the intestine of the cultured larvae did not show typical signs of dietary
phospholipid deficiency. These results suggest that requirements of nutrients such as 22∶6n-3 and taurine should be determined
for mass production of amberjack seeds. 相似文献
506.
Naoki SASAKI Yasunobu NISHI Yumi FUJIWARA Tetsuya TAKEYAMA Hayata KUMAGAI Samantha SENARATHNA Shigeto USHIYA Takashi TOKUYAMA Takahito TOKUYAMA Takaaki TOKUYAMA Tomohiro MII Satomi AYAKI Kosuke MATSUNO Yuki NAKAGAWA Yoshitaka NISHIHARA Yasuho TAURA 《Journal of Equine Science》2021,32(2):27
Gastric ulcers cause appetite loss, poor body condition, and colic in horses. This study investigated the protective effect of a rice fermented extract on the gastric mucosa in 17 healthy Thoroughbreds. For one month, horses in the rice fermented extract (nine horses) and control (eight horses) groups were orally administered a rice fermented extract (100%; 0.2 ml/kg, SID) and tap water (0.2 ml/kg), respectively. Gastric endoscopic images were obtained before and one month after rice fermented extract administration. The gastric ulcer score was lower after administration (median, 1; maximum, 2; minimum, 1) than before administration (median, 4; maximum, 4; minimum, 3) in the rice fermented extract group (P<0.05). In conclusion, the administration of a rice fermented extract for one month improves gastric mucosal lesions in Thoroughbreds with gastric ulcers. 相似文献
507.
Watarai M Yamato Y Horiuchi N Kim S Omata Y Shirahata T Furuoka H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(6):735-737
Lawsonia intracellularis is an obligate intracellular pathogenic bacterium that causes proliferative enteropathy in domestic and experimental animals. Antiserum against synthetic peptides of the Lawsonia surface antigen (LsaA) well recognized L. intracellularis in infected ileum by immunohistochemistry. The synthetic peptides in LsaA showed strong reaction with serum from rabbits infected with L. intracellularis by enzyme-linked immunosorbent assay. These results suggest that ELISA used synthetic peptides in LsaA and anti-LsaA serum might be useful to diagnose for proliferative enteropathy. 相似文献
508.
Nakamura M Tomizawa N Tohyama K Hara S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(7):767-772
Basic studies were carried out to apply frozen allogeneic nerve grafts in dogs after wide-ranging defects of the brachial plexus due to surgical resection of tumor. In this study, morphological variations in branching patterns of the brachial plexus were examined in ten beagle dogs, to evaluate whether the brachial plexus might represent a useful source of allogeneic nerve grafts. Spatial relationships between the axillary lymph node, which had the possibility of carcinomatous metastasis, and the musculocutaneous (MC) nerve, which was important for the function of the forelimbs, were also investigated. In all ten cases examined, the brachial plexus received ventral roots from the fifth cervical nerve to the first thoracic nerve. No significant variation in the branching pattern was found in any nerve except the phrenic, MC and dorsal thoracic nerves. Four communicating branches were observed and had some morphological variations which might be negligible for nerve grafting. Considering previous physiological and anatomical reports, the most important nerve to be reunited in graft operations for functional recovery is the radial nerve. The MC nerve and median or ulnar nerve should also be considered as possibilities for reuniting. Distances between the axillary lymph nodes and the MC nerve ranged from 11.2 mm to 21 mm (mean +/- SD: 16.1 +/- 2.3 mm). In conclusion, it was suggested that morphological variations in the brachial plexus were technically acceptable to apply allogeneic nerve grafts at least in beagle dogs. 相似文献
509.
Koga L Kobayashi Y Yazawa M Maeda S Masuda K Ohno K Tsujimoto H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(5):453-456
Vascular endothelial growth factor (VEGF) is an angiogenic factor which targets vascular endothelial cells. In this study, cDNA encoding a feline VEGF (fVEGF) isoform was cloned from a feline lymphoid tumor cell line and sequenced. The fVEGF cDNA contained an open reading frame of 567 nucleotides coding for a polypeptide of 163 amino acids with a putative signal peptide of 26 amino acids. The predicted fVEGF amino acid sequence shared 98.4, 94.2 and 94.2% homology with the sequences of canine, bovine and human VEGF, respectively. Though predicted fVEGF polypeptide was two amino acid residues shorter than human VEGF165, a potential glycosylation site and regions critical for receptor binding were conserved in all the species examined. Transient expression of fVEGF in mammalian cells resulted in secretion of VEGF which could be detected by antibodies against human VEGF165. Furthermore, wide expression of fVEGF mRNA was observed in various feline tissues using RT-PCR methods. 相似文献
510.