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61.
We investigated the extractability of manganese (Mn) and iron (Fe) oxides from typical Japanese soils (Entisols, Inceptisols, and Andisols) by 0.5?mol?L?1 hydroxylamine hydrochloride (NH2OH-HCl) extraction (pH 1.5; 16?h shaking at 25°C; soil:solution ratio 1:40), referred as to HHmBCR, which is Step 2 (used for the reducible fraction) of the modified BCR (Community Bureau of Reference) sequential extraction procedure. The HHmBCR procedure extracted almost all Mn oxides from the non-Andisol samples, but failed to extract a part of the Mn oxides from some Andisol samples. The procedure extracted most short-range ordered Fe oxides from non-Andisol samples, but it extracted only 7.5% and 13% of the short-range ordered Fe oxides from allophanic and non-allophanic Andisol samples, respectively. This remarkably low extractability of Fe oxides suggests that the HHmBCR method is not suitable for extracting oxide-occluded heavy metals from Andisols. Since the extraction rate of short-range ordered Fe oxides from various soils with the extractant was negatively correlated with the amounts of oxalate- and pyrophosphate-extractable Al even when the variability of the extraction pH was reduced by increasing the soil:solution ratio from 1:40 to 1:500, the extractability of Fe oxides would be negatively affected by the presence of active Al, including allophane/imogolite, amorphous Al, and Al-humus complexes. Because these Al constituents are abundant in Andisols, they would be at least partially responsible for the lower extractability of Fe oxides by HHmBCR from Andisols. 相似文献
62.
Tomoyuki Makino Syuichi Hasegawa Yasuhiro Sakurai Satoshi Ohno Hirokatsu Utagawa Yuji Maejima 《Soil Science and Plant Nutrition》2013,59(3):581-590
Abstract The changes in the exchangeable Mn (Ex-Mn), exchangeable Co (Ex-Co), and exchangeable Cu (Ex-Cu) contents by air-drying of soils were reported in our previous paper. The drying effect, however, was not analyzed in the field. The objective of this study was to investigate the influence of soil-drying under field conditions on Ex-Mn, Ex-Co, and Ex-Cu levels. Two paddy soils (Tsukuba and Yawara) were collected at four different soil depths (0?1, 1?5, 5?10, and 10?20 cm) under three different soil moisture conditions i.e., after harvest, after successive sunny days and after rainy days. After sunny days, Ex-Mn and Ex-Co contents in the surface soil layer markedly increased and drastically decreased after rainfall, while they remained almost unchanged in the lower soil layers. Ex-Cu contents slightly increased in the surface soil layer after sunny days. A similar tendency was observed in soil column experiments. The contents of Ex-Mn, Ex-Co, and Ex-Cu increased 12, 12, and 2 times in the upper layer of soil columns that had been sampled from the Yawara field and stored in a dark room for 8 d. The increase of the Ex-Mn and Ex-Co contents in the upper layer could not be explained by the capillary rise of soil water from the lower layers of the columns. In a soil-drying experiment under laboratory conditions, Ex-Mn and Ex-Co contents began to increase when the water content of the Yawara soil was lower than 0.09?0.13 kg kg?1. The water content of the surface soil of the Yawara field after sunny days was 0.08 kg kg?1. Ex-Cu content did not change apprecially with the water content. It is concluded that the increase of the Ex-Mn and Ex-Co levels in field surface soils after sunny days can be ascribed to soil-drying. Some of the excess Ex-Mn and Ex-Co is expected to leach down into lower layers due to rain, which may contribute to plant uptake of Mn and Co. 相似文献
63.
A new cytotoxic 25-membered macrolide, amphidinolide C2 (1), has been isolated from marine dinoflagellate Amphidinium sp. (Y-71 strain), and the structure 1 was elucidated on the basis of spectroscopic data and chemical means. 相似文献
64.
Tomoyuki Nakatsubo Yu Kitamura Norikazu Sakakibara Masaharu Mizutani Takefumi Hattori Nozomu Sakurai Daisuke Shibata Shiro Suzuki Toshiaki Umezawa 《Journal of Wood Science》2008,54(4):312-317
The function of an Arabidopsis thaliana gene, At5g54160 annotated as a caffeic acid O-methyltransferase CAOMT gene was characterized. The recombinant enzyme of this gene (AtOMT1) catalyzed the O-methylation of phenylpropanoid and flavonoid substrates. The specificity constants (k
cat/K
m) for 5-hydroxyconiferaldehyde (5-HCAld) and quercetin were both 0.11 μM−1·min−1. On the other hand, lignins of At5g54160-knockout Arabidopsis mutants lacked syringyl units. In addition, we showed that the gene silencing also resulted in significant accumulation of
caffeyl alcohol (CaAlc). These results strongly suggested that At5g54160 gene is involved in syringyl lignin synthesis for
the methylation of both 5-hydroxyconiferaldehyde and 3,4-dihydroxyphenyl compound(s).
Part of this work was presented at the Annual Meeting of Japan Society for Bioscience, Biotechnology, and Agrochemistry, March
24–27, 2007 相似文献
65.
Yosuke Matsushita Tomio Usugi Shinya Tsuda 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(2):349-352
We characterised the host range and physical properties of Tomato chlorotic dwarf viroid. Among the 46 plant species inoculated with the viroid, two in the family Compositae and 23 in the family Solanaceae were
found to be systemic hosts. The viroids in the crude sap from diseased tomato plants were thermally inactivated by heating
to 100°C for at least 40 min. These viroids also lost their infectivity when diluted in phosphate buffer to at least 10−6, or after 3 days of incubation at room temperature. However, the infectivity of the viroids in dried crude sap from the plants
persisted throughout the 50-day test period. 相似文献
66.
Naomi JACK Tomoyuki MUTO Keigo IEMITSU Tamaki WATANABE Kazuhiro UMEYAMA Jun OHGANE Hiroshi NAGASHIMA 《The Journal of reproduction and development》2022,68(4):233
Recent developments in reproductive biology have enabled the generation of genetically engineered pigs as models for inherited human diseases. Although a variety of such models for monogenic diseases are currently available, reproduction of human diseases caused by haploinsufficiency remains a major challenge. The present study compares the phenotypes of mouse and pig models of Marfan syndrome (MFS), with a special focus on the expressivity and penetrance of associated symptoms. Furthermore, investigation of the gene regulation mechanisms associated with haploinsufficiency will be of immense utility in developing faithful MFS pig models. 相似文献
67.
Two strains of Mongolian gerbils (Meriones unguiculatus), Tumble Brook (TUM) and Japan Medical Science (JMS), were intraperitoneally inoculated with the D variant of encephalomyocarditis virus (EMC-D) and killed 3 days later. Mortality was significantly higher in females than in males. Evidence of viral replication was detected in the heart of both strains and in the pancreas of the TUM strain. Histopathological alterations were found in the heart and pancreas. Heart lesions involved foci of necrosis with inflammatory cell infiltration and calcification in both strains. Pancreatic lesions were restricted to the exocrine glands; islets of Langerhans were rarely and secondarily involved in the extensive destruction of exocrine glands. Severe acinar cell necrosis with marked inflammatory edema was conspicuous in TUM, whereas only slight acinar cell involvement was detected in JMS gerbils. Immunoperoxidase staining showed viral antigens in intracytoplasmic vacuoles in damaged acinar cells. 相似文献
68.
69.
Hitoshi Watanabe Shuji Tsuda Jun-ichi Fukami 《Pesticide biochemistry and physiology》1975,5(2):150-154
The effects of chlordimeform on rectus abdominis muscle of frog were investigated. Chlordimeform (10?3M) caused a slow contraction, and at lower concentration (10?5–10?3M) it inhibited the acetylcholine-induced contraction in noncompetitive manner. When chlordimeform was applied to the muscle of Rana catesbiana, K+-induced contraction was also inhibited in noncompetitive manner. Whereas it had no effect on caffeine-induced contraction.Chlordimeform-induced contraction was not affected by respective addition of d-tubocurarine (10?4M), procaine (10?3M), or eserine (0.3 mM), which results were same as that of K+-induced contraction. Chlordimeform, at lower concentration (10?5–10?3M), inhibits the acetylcholine- and K+-induced contractions probably owing to depression of not only the sensitivity of endplate but also the excitability of cell membrane. 相似文献
70.
Bacteriological evaluation of composted manure solids prepared from anaerobic digested slurry for hygienic recycled bedding materials for dairy cows
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Eiryu Okamoto Hiroki Miyanishi Akinobu Nakamura Tomoyuki Kobayashi Norihiko Kobayashi Yoshinori Terawaki Hajime Nagahata 《Animal Science Journal》2018,89(4):727-732
Changes in mastitis‐causing pathogens, pH and water content in composted manure solids (CMS) prepared from digested slurry were evaluated during turning at 2‐day intervals for 8 days (C1–C4). The numbers of streptococci, coagulase‐negative staphylococci and coliforms were 2.6 × 101, 1.7 × 102 and 1.0 × 101 colony‐forming units (cfu)/g in CMS (C4) (summer), and these counts were markedly lower (P < 0.05) than those in CMS (C0 and C1). The bacterial counts ranged from 101 to 1.7 × 102 cfu/g in CMS (C4) (summer) and were within approved levels, <1 × 106 cfu/g, indicating a minimal mastitis risk. The temperatures in CMS (C1–C4) increased to 63°C–74°C in summer and 67°C–70°C in winter. The mean pH values in CMS (C0–C4) were 9.2 in summer and 8.7 in winter, and water contents ranged from 61.7% to 69.6% in summer and 73.2% to 66.2% in winter. The significant decrease of pathogenic bacteria in CMS appears to be closely related to temperature >63°C for 8 days, pH 8.7–9.2, and water content 62% to 73%. This study demonstrates that prepared CMS has value as a recycled material with the potential to alleviate udder health issues in dairy cows. 相似文献