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31.
L. Barbiero A. Rezende Filho S.A.C. Furquim A.Y. Sakamoto R.C. Graham R.P.D. Ferreira 《Geoderma》2008,148(1):91-106
Joint pedological, geochemical, hydrological and geophysical investigations were performed to study the coexistence of saline and freshwater lakes in close proximity and similar climatic conditions in the Nhecolândia region, Pantanal wetlands in Brazil. The saline lakes are concentrically surrounded by green sandy loam horizons, which cause differential hydrological regimes.Mg-calcite, K-silicates, and amorphous silica precipitate in the soil cover, whereas Mg-silicates and more soluble Na-carbonates are concentrated in the topsoil along the shore of the saline lake. In saline solutions, some minor elements (As, Se) reach values above the water quality recommendations, whereas others are controlled and incorporated in solid phases (Ba, Sr). Locally, the destruction of the sandy loam horizons generates very acidic soil solution (pH ~ 3.5) through a process not yet understood. The soil distributions indicate that some freshwater lakes are former saline lakes. They are invaded by freshwater after destruction of the sandy loam green horizons, then the freshwater becomes enriched in K+, SO42−, Fe, Al, and a stream of minor and trace elements. The formation of these green sandy loam horizons in the saline environment and their destruction in the non-saline one emphasizes the dynamic nature of this environment. 相似文献
32.
Invertebrate drift is one of several fundamental ecological processes in streams. However, little is known about the dynamics of invertebrate drift in Kenyan streams. In this study, we assessed invertebrate drift in two rivers, i.e. Njoro and Kamweti, that differ in the level of anthropogenic disturbances, between February and March, 2016. The aim was to evaluate the effect of river sampling duration (5, 10, 15, 20 and 25 min) and sampling period (day or night) on invertebrate drift densities. The 5-minute sampling period resulted in significantly higher mean drift densities than the other time intervals in both rivers. The highest mean drift density (2.0 ± 0.9 individuals m?3) was recorded at the Njoro River during the day, whereas the lowest drift density (0.3 ± 0.2 individuals m?3) was recorded at the Kamweti River during the day. A strong nocturnal drift pattern was noted at the less disturbed river (Kamweti). The present results suggest that anthropogenic perturbations influence invertebrate drift densities, and sampling duration and sampling period are important factors to consider when sampling invertebrate drift. 相似文献
33.
Analysis of Phytosterol,Fatty Acid,and Carotenoid Composition of 19 Microalgae and 6 Bivalve Species
Risako Hikihara Yasuhiro Yamasaki Tomoyuki Shikata Natsuko Nakayama Setsuko Sakamoto Sueo Kato 《Journal Of Aquatic Food Product Technology》2020,29(5):461-479
ABSTRACTIn this study, the functional components of 19 microalgae and 6 bivalve species were investigated in the context of the application in bivalve feeding and human health food. Principal component analysis was performed to detect any association between the functional components and individual microalgal species or taxonomic group. The proportions of the functional components differed depending on the taxonomic group or species of microalga. The genera Cheatoceros, Thalassiosira, and Isochrysis contained high concentrations of fucosterol and fucoxanthin, which are present in large amounts in brown algae. Diatoms, haptophytes, and eustigmatophytes, which are used as feed for bivalves, were rich in fucosterol and eicosapentenoic acid (EPA); further, haptophytes were rich in docosahexaenoic acid (DHA). In addition, the microalgae associated with red tide, i.e., the raphidophytes, were found to be rich in fucoxanthin, β-sitosterol, and EPA, whereas dinoflagellates were rich in DHA. Seven bivalve species also contained high concentrations of fucosterol, EPA, and DHA, as did microalgae, which were used to feed by bivalves. These results are useful in selecting microalgae effectively as feed of the bivalves. 相似文献
34.
Christopher J. Fulton Charlotte Berkstrm Shaun K. Wilson Rene A. Abesamis Michael Bradley Carolina kerlund Luke T. Barrett Abner A. Bucol Dinorah H. Chacin Karen M. Chong‐Seng Darren J. Coker Martial Depczynski Linda Eggertsen Maria Eggertsen David Ellis Richard D. Evans Nicholas A. J. Graham Andrew S. Hoey Thomas H. Holmes Michel Kulbicki Priscilla T. Y. Leung Paul K. S. Lam Joshua van Lier Paloma A. Matis Mae M. Noble Alejandro Prez‐Matus Camilla Piggott Ben T. Radford Stina Tano Paul Tinkler 《Fish and Fisheries》2020,21(4):700-717
Canopy‐forming macroalgae can construct extensive meadow habitats in tropical seascapes occupied by fishes that span a diversity of taxa, life‐history stages and ecological roles. Our synthesis assessed whether these tropical macroalgal habitats have unique fish assemblages, provide fish nurseries and support local fisheries. We also applied a meta‐analysis of independent surveys across 23 tropical reef locations in 11 countries to examine how macroalgal canopy condition is related to the abundance of macroalgal‐associated fishes. Over 627 fish species were documented in tropical macroalgal meadows, with 218 of these taxa exhibiting higher local abundance within this habitat (cf. nearby coral reef) during at least one life‐history stage. Major overlap (40%–43%) in local fish species richness among macroalgal and seagrass or coral reef habitats suggest macroalgal meadows may provide an important habitat refuge. Moreover, the prominence of juvenile fishes suggests macroalgal meadows facilitate the triphasic life cycle of many fishes occupying diverse tropical seascapes. Correlations between macroalgal canopy structure and juvenile abundance suggests macroalgal habitat condition can influence levels of replenishment in tropical fish populations, including the majority of macroalgal‐associated fishes that are targeted by commercial, subsistence or recreational fisheries. While many macroalgal‐associated fishery species are of minor commercial value, their local importance for food and livelihood security can be substantial (e.g. up to 60% of landings in Kenyan reef fisheries). Given that macroalgal canopy condition can vary substantially with sea temperature, there is a high likelihood that climate change will impact macroalgal‐associated fish and fisheries. 相似文献
35.
Felipe SRM. Andrade Lara L. Facó Keila K. Ida Luis CLC. Silva Denise T. Fantoni Aline M. Ambrósio 《Veterinary anaesthesia and analgesia》2019,46(1):64-73
Objective
To compare static compliance (Cst) and alveolar–arterial oxygen tension difference [P(a–a)O2] between positive end-expiratory pressures (PEEP) of 7, 12 and 17 cmH2O applied after an alveolar recruitment maneuver (RM) in isoflurane-anesthetized horses.Study design
Prospective, randomized, clinical study.Animals
A group of 30 healthy adult horses undergoing arthroscopic surgery.Methods
Animals in dorsal recumbency and mechanically ventilated with a tidal volume of 14 mL kg?1 and 7 cmH2O PEEP (control; n = 6) were subjected to an RM by increasing PEEP from 7 to 22 cmH2O in 5 cmH2O increments at 5 minute intervals, and then decreased similarly to PEEP of 17 (RM17; n = 8), 12 (RM12; n = 8) or 7 cmH2O (RM7; n = 8). Cst and P(a–a)O2 were assessed prior to (baseline) and after the RM at 5, 10, 15, 20, 40, 60 and 80 minutes after achieving each target PEEP, and during recovery from anesthesia.Results
Post-RM improvements on P(a–a)O2 were maintained (baseline versus 80 minutes) in RM12 [216 ± 77 mmHg (28.8 ± 10.3 kPa) versus 194 ± 39 mmHg (25.9 ± 5.2 kPa)] and RM17 [180 ± 86 mmHg (24.0 ± 11.6 kPa) versus 136 ± 75 mmHg [18.2 ± 10.0 kPa]). The improvements on Cst were maintained only in RM12 (0.80 ± 0.13 versus 0.98 ± 0.13 mL cmH2O?1 kg?1). No such improvements were observed in RM7 and control. No significant differences were observed between groups during recovery from anesthesia.Conclusions
and clinical relevance The 12 and 17 cmH2O PEEP can be used to maintain the improvements on P(a–a)O2 obtained after an RM. Only 12 cmH2O PEEP maintained the post-RM increase on Cst. Such variables were not influenced by the 7 cmH2O PEEP. 相似文献36.
Yurimoto H Abe K Abe M Ebihara M Fujimura A Hashiguchi M Hashizume K Ireland TR Itoh S Katayama J Kato C Kawaguchi J Kawasaki N Kitajima F Kobayashi S Meike T Mukai T Nagao K Nakamura T Naraoka H Noguchi T Okazaki R Park C Sakamoto N Seto Y Takei M Tsuchiyama A Uesugi M Wakaki S Yada T Yamamoto K Yoshikawa M Zolensky ME 《Science (New York, N.Y.)》2011,333(6046):1116-1119
Meteorite studies suggest that each solar system object has a unique oxygen isotopic composition. Chondrites, the most primitive of meteorites, have been believed to be derived from asteroids, but oxygen isotopic compositions of asteroids themselves have not been established. We measured, using secondary ion mass spectrometry, oxygen isotopic compositions of rock particles from asteroid 25143 Itokawa returned by the Hayabusa spacecraft. Compositions of the particles are depleted in (16)O relative to terrestrial materials and indicate that Itokawa, an S-type asteroid, is one of the sources of the LL or L group of equilibrated ordinary chondrites. This is a direct oxygen-isotope link between chondrites and their parent asteroid. 相似文献
37.
Hosaka Y Sakamoto Y Kirisawa R Watanabe T Ueda H Takehana K Yamaguchi M 《The Japanese journal of veterinary research》2004,52(3):135-144
Although tumor necrosis factor (TNF) alpha is an important key factor in degeneration of equine superficial digital flexor tendon (SDFT), the dynamism of TNF receptors and associated factors on tendinocytes has not been elucidated. To reveal signaling events mediated by TNF-receptors (TNF-Rs) in tendinocytes, we focused on four signaling factors, TNF-R1, TNF-R2, TNF-R-associated factor 2 (TRAF2) and nuclear factor-kappa B (NF-kappaB), and investigated the distribution and production of these factors. Cultured tendinocytes were obtained from SDFTs of thoroughbred horses. The tendinocytes were treated with 10 ng/ml equine TNFalpha medium for 6 hours and then the four factors on tendinocytes were visualized by using an immunohistochemical method, and the amounts of the four factors were determined by Western blot analysis. Although TNF-R1 and TNF-R2 co-localized on the same tendinocyte, in untreated control cells (normal condition), immunoreactivity against TNF -R1 was very weak but TNF-R2 showed a strong reaction. However, TNF-R1 showed the same high level of reaction as TNF-R2 in TNFalpha-treated cells (inflamed condition). Intense TRAF2 and NF-kappaB were detected at inflamed condition, however both factors were also detected at normal condition. The distinct distributions of the four factors under different conditions (normal and inflamed condition) in vitro not only reflect the dynamism of the cytokines but may also provide important clues for a means to prevent from occurrence of tendonitis and progress of tendon degeneration. 相似文献
38.
Transcription of thymic stromal lymphopoietin via Toll‐like receptor 2 in canine keratinocytes: a possible association of Staphylococcus spp. in the deterioration of allergic inflammation in canine atopic dermatitis 下载免费PDF全文
Mayu Sakamoto Ryota Asahina Hiroaki Kamishina Sadatoshi Maeda 《Veterinary dermatology》2016,27(3):184-e46
39.
Murakami T Kobayashi Y Chiba S Kurauchi Y Sakamoto H Sasaki M Matsui T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(9):1195-1197
Humeral chondrosarcoma was found in an 18-year-old male Hokkaido brown bear (Ursus arctos yesoensis). Necropsy revealed a large firm mass under the left superficial pectoral muscle at the axillary region. The mass involved the left shoulder joint and peripheral muscles, and connected to the head of the humerus with osteolysis. Histopathologically, the mass was composed of irregularly shaped myxomatous to cartilaginous tumor lobules. The tumor cell showed moderate nuclear atypia with a relatively high mitotic index, especially in the edges of the myxomatous lobules. The tumor cells were positively immunostained with vimentin and S-100 protein. Based on these findings, the tumors were diagnosed as chondrosarcoma. Metastases were found in the left axillary lymph node, lungs, liver and kidney. 相似文献
40.
Denise T. Fantoni Keila K. Ida André M. Gimenes Matheus M. Mantovani Jacqueline R. Castro Geni C.F. Patrício Aline M. Ambrósio Denise A. Otsuki 《Veterinary anaesthesia and analgesia》2017,44(4):710-718