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1.
Fisheries Science - The novel organic selenium compound, selenoneine, is found in the blood of tuna and has metal-binding activity. In this report, selenoneine displays tyrosinase inhibitory...  相似文献   
2.
Extremely low post-settlement survival is one of the largest barriers for artificial rehabilitation of Acropora corals. However, little data have been found for interspecific difference of the post-settlement survival probably because the observation of coral juvenile is difficult in the field. Here, we analyzed the survival of three dominant species of Acropora corals (A. digitifera, A. tenuis, A. yongei), with different colony morphologies and habitat preferences, for 2 years after settlement under the same environmental conditions. The post-settlement survival was significantly higher for A. tenuis than for A. digitifera 3 months after settlement. Two years later, the survival rate of A. tenuis was approximately 15 times higher than A. digitifera. In a separate analysis of three bottle-brush species (A. awi, A. echinata, A. subglabra) and A. tenuis, post-settlement survival was always higher for A. awi than for other two bottle-brush species, suggesting that the initial survival was different among morphologically sister species. Low survival was possibly associated with slow growth rates during the first 7 months. Thus, species selection is important for successful artificial coral rehabilitation, with A. tenuis being the most viable option. Alternatively, new techniques are required to improve post-settlement survival of slow growing coral species.  相似文献   
3.
Hydrographic conditions and distributions of juvenile temperate sea bass Lateolabrax japonicus were observed in early spring from 2009 to 2012 in the Yura River estuary, which is highly stratified due to its small tides and consequent seawater intrusion into the bottom layer of the river as a salt wedge. In all four studied years, the upstream expansion of their distribution coincided with the timing of the salt wedge intrusion from the lower to upper estuary, indicating that juvenile fish used salt wedge intrusions to ascend the estuary in early spring. However, juveniles sometimes remained in the nearshore area even when the salt wedge intrusion had already occurred, indicating that other triggers are also likely to be necessary. We therefore evaluated the effects of temperature on upstream migration behaviors. The relationship between the mean temperature they experienced from hatch until starting the ascent and mean age of each cohort at the upstream migration fitted with the law of effective cumulative temperature. Most cohorts ascended the river at an effective cumulative temperature of approximately 500 °C–days. This suggests that higher temperatures would lead to a shorter period prior to the upstream migration.  相似文献   
4.
The trace element contents of Corbicula clam shells collected from Japan, Russia, China, and the Republic of Korea were analyzed to determine their geographic origin. The crushed shells were decomposed with nitric acid–hydrogen peroxide, and the concentrations of 14 elements (Li, Mg, V, Mn, Co, As, Rb, Mo, Ba, Ce, Pb, U, Sr, and Ca) were measured by inductively coupled plasma mass spectrometry and inductively coupled plasma optical emission spectrometry. Some of the elements identified in samples displayed a geographic trend. The average content of manganese in Japanese samples was twice that of Russian samples. Conversely, the arsenic content in Japanese samples was approximately half of that in Russian samples. Linear discriminant analysis was applied to the data from Japanese and Russian samples, and a discriminant model was constructed. The discriminant model was used to determine the geographic origin of Corbicula clams produced in Japan, with 89.8 % of those identified as Japanese and 92.2 % of those identified as Russian being classified correctly. Therefore, trace element analysis of the shells of Corbicula clams is a useful technique for the identification of their country of origin.  相似文献   
5.
An 8.0-kg 8-year-old male dachshund was presented for surgical treatment of suspected pituitary-dependent hyperadrenocorticism with portal vein thrombosis. Advanced diagnostic imaging revealed a thrombus in the splenic and portal veins. For the portal vein thrombus, CT angiography showed an enhanced timing delay in the lateral right and caudate liver lobes. Blood tests showed a marked increase in the liver panel, including total bile acid. Brain MRI revealed a pituitary mass, suggesting pituitary-dependent hyperadrenocorticism. The mass was completely resected. The preoperative antithrombotic therapy of rivaroxaban (0.66 mg/kg, PO, once per day) and clopidogrel sulphate (1.66 mg/kg, PO, once per day) was continued postoperatively. Six months after resection of the pituitary mass, the thrombus had disappeared. Further studies are required to prove a causal association between the disappearance of the thrombus and the treatments provided.  相似文献   
6.
Mitigation of nitrous oxide (N2O) emission from swine wastewater treatment was demonstrated in an aerobic bioreactor packed with carbon fibers (CF reactor). The CF reactor had a demonstrated advantage in mitigating N2O emission and avoiding NOx (NO3 + NO2) accumulation. The N2O emission factor was 0.0003 g N2O‐N/gTN‐load in the CF bioreactor compared to 0.03 gN2O‐N/gTN‐load in an activated sludge reactor (AS reactor). N2O and CH4 emissions from the CF reactor were 42 g‐CO2 eq/m3/day, while those from the AS reactor were 725 g‐CO2 eq/m3/day. The dissolved inorganic nitrogen (DIN) in the CF reactor removed an average of 156 mg/L of the NH4‐N, and accumulated an average of 14 mg/L of the NO3‐N. In contrast, the DIN in the AS reactor removed an average 144 mg/L of the NH4‐N and accumulated an average 183 mg/L of the NO3‐N. NO2‐N was almost undetectable in both reactors.  相似文献   
7.
AIM: To investigate the effects and mechanisms of sphingosine-1-phosphate receptor-2 (S1P2R)on lipopolysaccharide (LPS)-induced acute lung injury (ALI). METHODS: ALI model was induced by intratracheal administration of LPS in both wild-type mice and S1P2R -deficient mice. The pathological changes in the lung tissues were observed, and the protein concentration, total cell number, neutrophil ratio, TNF-α level and IL-6 level were determined in the bronchoalveolar lavage fluid (BALF) 24 h after LPS injection. In order to investigate the mechanisms of S1P2R in LPS-induced ALI, 10 min before LPS injection, both wild-type mice and S1P2R -deficient mice were injected with nitric oxide synthase inhibitor by tail vein injection, the pathological changes of the lung tissues were observed, and the protein concentration and total cell number in BALF were determined 12 h after LPS injection. RESULTS: Compared with wild-type mice, S1P2R -deficient mice showed more severe LPS-induced ALI, and the protein concentration, neutrophils and inflammatory cytokines in BALF were significantly increased in S1P2R -deficient mice. Administration of nitric oxide synthase inhibitor Nω-L-nitro-arginine methyl ester protected S1P2R -deficient mice from aggravation of ALI. CONCLUSION: S1P2R mediates the protection from LPS-induced ALI possibly through inhibiting nitric oxide synthase.  相似文献   
8.
Data have been compiled from published sources on nitrogen (N) fluxes in precipitation, throughfall, and leaching from 69 forest ecosystems at 50 sites throughout China, to examine at a national level: (1) N input in precipitation and throughfall, (2) how precipitation N changes after the interaction with canopy, and (3) whether N leaching increases with increasing N deposition and, if so, to what extent. The deposition of dissolved inorganic N (DIN) in precipitation ranged from 2.6 to 48.2 kg N ha−1 year−1, with an average of 16.6 kg N ha−1 year−1. Ammonium was the dominant form of N at most sites, accounting for, on average, 63% of total inorganic N deposition. Nitrate accounted for the remaining 37%. On average, DIN fluxes increased through forest canopies, by 40% and 34% in broad-leaved and coniferous forests, respectively. No significant difference in throughfall DIN inputs was found between the two forest types. Overall, 22% of the throughfall DIN input was leached from forest ecosystems in China, which is lower than the 50–59% observed for European forests. Simple calculations indicate that Chinese forests have great potential to absorb carbon dioxide from the atmosphere, because of the large forest area and high N deposition.  相似文献   
9.
Bamboo-derived activated carbon prepared by superheated steam (BAC) exhibited performance for utilization as an electric double layer capacitor (EDLC) electrode. Pore structure and EDLC performances were investigated by comparison with phenol resin-derived activated carbon (MSP-20), which is commercially available and often used for the purpose. The nitrogen adsorption isotherm showed that BAC had a large BET-specific surface area of 1268 g/m2 with a developed pore structure, especially of the mesopore, in comparison with MSP-20. It is considered that inherent ash in bamboo promoted activation, in addition to physical activation by superheated steam. Capacitance per electrode volume (CV) was 52 F/cm3 with BAC. Because the density of BAC is high (0.78 g/cm3) compared with that of MSP-20 (0.58 g/cm3), sufficient CV for usage was obtained, although the capacitance per electrode mass (CM) at 5 mA/cm2 itself of BAC (67 F/g) was lower than that of MSP-20 (126 F/g). With IR drop, the resistance value of BAC (9.7 Ω) was lower than that of MSP-20 (10.5 Ω). Especially, the diffusion resistance of BAC disclosed to be smaller than that of MSP-20. These results indicated that BAC produced by steam activation is a promising material with a pore structure suitable for ion transfer in EDLC.  相似文献   
10.
Northwesterly cold winds characteristic of the East Asian Winter Monsoon (EAWM) dictate winter climatic conditions over the Japanese Archipelago. Japanese temperate bass Lateolabrax japonicus is a commercially important coastal fish that spawns offshore in winter and uses shallow waters as nursery habitats. To investigate the effects of EAWM on the planktonic period of L. japonicus, eggs, larvae, and juveniles were quantitatively collected in Tango Bay on the Sea of Japan side in winter and spring from 2007 to 2017. Although eggs occurred close to the mouth of the bay, planktonic larvae occurred further inside as they developed. The horizontal distribution of planktonic larvae, combined with water velocity data obtained from mooring observations, indicated that planktonic larvae are transported south‐ to westward through Ekman current and an anticyclonic circulation, which are driven by northwesterly winds. To evaluate survival during the planktonic period in each year class, the abundance of benthic larvae/juveniles was divided by winter total landings of Lateolabrax spp. (proxy of the spawning stock size). This survival index exhibited a positive correlation with the northwesterly component of winter winds, and a negative correlation with winter air temperature (average from December to February, Spearman's correlation, p < .05). There was, however, no significant correlation with winter water temperature or winter freshwater discharge in the bay. We conclude that northwesterly cold winds of EAWM play a critical role in transporting L. japonicus eggs and larvae toward nursery habitats, specifically beaches and estuaries fringing the innermost part of Tango Bay.  相似文献   
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