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1.
Jeannette S. Bayuelo-Jiménez Takashi Muraoka Eulogio de la Cruz-Torres Esperanza Quintero-Ponce Lydia C. Paredes-Gutiérrez Mohammad Zaman 《Soil Use and Management》2020,36(2):240-249
Land-use change from forest to agriculture in the volcanic ash-derived soils of Mexico has increased over recent decades. It is likely that land uses and management practices, particularly fertilizer use have affected phosphorus (P) distribution and availability. The objective of this study was to evaluate the effects of land-use types (native forest and maize mono-cropping), and the related P addition, on the forms and distribution of soil P and their isotopic exchangeability. An Andisol, sampled from a cropping site, along with the contiguous area under native forest was treated with 32P-labelled potassium phosphate (KH232PO4). The soil samples were extracted after incubation times of 7, 21, 35 and 49 days. Phosphorus content and 32P recovery in fractions sequentially extracted were assessed for each incubation time. Total soil P was dominated by inorganic fractions (79 to 86%) in both land-use types. Resin-Pi, bicarbonate extractable inorganic P (Bic-Pi) and sodium hydroxide extractable inorganic P (NaOH0.1-Pi) were all raised with P addition. However, the proportion of organic P fraction was reduced under cropped soil. The recovery of 32P in soils with P addition indicates that resin-Pi, Bic-Pi and NaOH0.1-Pi comprised nearly all the exchangeable P. In native soils with no P addition, more than 19% of the 32P was recovered in Bic-Po and NaOH0.1-Po forms. This finding indicates that organic P cycling is crucial when soil Pi reserves are presented in an inadequate amount. Ecologically based management has to be designed for replenishment and succeeding maintenance of soil organic P compounds to increase sustainable agricultural production. 相似文献
2.
Thanankorn Jaiphong Jun Tominaga Kenta Watanabe Ryuichi Suwa Masami Ueno 《Plant Production Science》2017,20(1):126-135
Sugarcane (Saccharum spp.) is an economical crop in the tropical and subtropical countries. However, because of global climate change, flooding has become problematic, particularly during the rainy season, in Thailand. We investigated the effects of floods on three commercial sugarcane cultivars, namely NiF8, U-thong 6 (UT6), and U-thong 9 (UT9), as well as Erianthus spp. Growth was assessed using a pot experiment in a glasshouse with two treatments: (1) control and (2) 60 d of flooding followed by 30 d of normal conditions. In comparison with control, during prolonged flooding, Erianthus showed greatly decreased CO2 assimilation, whereas NiF8, UT6, and UT9 showed slightly declined CO2 assimilation. Growth in plants subjected to 60 d of flooding was less influenced by floods while sucrose content was not affected except in UT6. During flooding, some roots died, resulting in plants compensating adventitious roots to offset the negative effects of root death and to assist them in maintaining their growth, which appeared from the submerged nodes, with different characteristics for each cultivar. However, 30 d after draining, roots remained damaged, while adventitious roots died, resulting in lesser growth as compared with the control, but it did not significantly affect sucrose content and sugar yield. This study suggests that sugarcane plants need to produce the adventitious roots to compensate their roots’ death during flooding and require time to recover their root system after flooding for obtaining the optimum yield and quality at harvest. 相似文献
3.
Fisheries Science - Bioturbation by the sand dollar Scaphechinus griseus is suspected to inhibit the recruitment of Pseudocardium sachalinense, a commercially important bivalve. This study aimed to... 相似文献
4.
Nakagawa Koki Murase Jun Asakawa Susumu Watanabe Takeshi 《Journal of Soils and Sediments》2020,20(11):4034-4041
Journal of Soils and Sediments - To reveal whether microaerophilic Fe(II)-oxidizing bacteria (FeOB) participate in the Fe(II) oxidation at the oxic-anoxic interface in flooded paddy field soil,... 相似文献
5.
Okajima Kenji Nagaoka Seiya Islam Mohammad Raihanul Ito Ryouei Watanabe Ken 《Paddy and Water Environment》2020,18(2):345-353
Paddy and Water Environment - Repairs of concrete irrigation channels in Japan are guided to a large extent by the degree to which their walls have degraded over decades of use. Current methods of... 相似文献
6.
Chiaki Ikeda Yuki Manabe Nami Tomonaga Tatsuya Wada Takashi Maoka Tatsuya Sugawara 《Marine drugs》2020,18(12)
Halocynthiaxanthin is an acetylenic carotenoid mainly found in Halocynthia roretzi. To date, several bioactivities of halocynthiaxanthin have been reported, but its mechanism of digestion and absorption in mammals has not been studied yet. In this study, we evaluated the intestinal absorption of halocynthiaxanthin in mice. The halocynthiaxanthin-rich fraction was prepared from the tunicate Halocynthia roretzi. Mice were orally administered the fraction at a dose of 5 mg/kg body weight. The halocynthiaxanthin levels in the plasma, liver, and small intestine, were quantified using HPLC-PDA, 1, 3, 6, and 9 h after ingestion. The halocynthiaxanthin-rich fraction mainly consisted of the all-trans form and a small amount of cis forms. These three isomers were detected in the plasma of mice 3 h after ingestion. Time-course changes after the ingestion of this fraction were found, with cis isomers being more abundant than the all-trans isomer in the mouse plasma and liver. In the small intestine, however, the all-trans isomer was primarily detected. The possibility that cis isomers might be absorbed rapidly from the small intestine cannot be denied, but our results suggest that dietary all-trans-halocynthiaxanthin might be isomerized to the cis isomer after intestinal absorption. 相似文献
7.
Tadahisa MASHITA Hiroaki KAMISHINA Yuya NAKAMOTO Yosuke AKAGI Ataru NAKANISHI Yusuke HARASAKI Tsuyoshi OZAWA Takashi UEMURA Yui KOBATAKE Shunsuke SHIMAMURA Naoki KITAMURA Sadatoshi MAEDA Yuji UZUKA Gerry SHAW Jun YASUDA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(4):433-438
The aim of this study was to evaluate the prognostic value of concurrent measurement of
serum phosphorylated neurofilament heavy subunit (pNF-H) concentration and intramedullary
T2W hyperintensity in paraplegic to paraplegic dogs. Our hypothesis was that concurrent
measurement of these would provide a more accurate prediction of functional outcome in
dogs with thoracolumbar intervertebral disc herniation (IVDH). A prospective case-control
clinical study was designed using 94 dogs with acute onset of thoracolumbar IVDH. The
association of serum pNF-H concentration, T2W hyperintensity on sagittal MRI (T2H/L2),
deep pain perception and surgical outcome were evaluated with logistic regression analysis
after three months for all 94 surgically treated dogs. Sensitivity to predict
non-ambulatory outcome was compared among pNF-H and T2H/L2 and combination of both.
Logistic regression analysis indicated that serum pNF-H concentration and T2H/L2 were
significantly correlated with surgical outcome (P<0.05); however, deep
pain perception was not (P=0.41). The results of logistic regression
analysis indicated that the odds ratios of unsuccessful long-term outcome were 2.6 for
serum pNF-H concentration, 1.9 for T2H/L2 and 2.3 for deep pain sensation. The sensitivity
and specificity to predict non-ambulatory outcome for using serum parameter pNF-H>2.6
ng/ml, using T2H/L2 value of>0.84 and using both
serum pNF-H and T2H/L2, were 95% and 75.7%, 65% and 86.5%, and 90.0% and 97.5%,
respectively. Therefore, combined measurements of serum pNF-H and T2H/L2 might be useful
for predicting long-term outcome in dogs with thoracolumbar IVDH. 相似文献
8.
Tsukasa OKANO Katsuhi NAKATA Yumiko NAKAYA Takashi NAGAMINE Manabu ONUMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(6):637-642
The Ryukyu long-furred rat, Diplothrix legata, is a large rodent
distributed only on Amami-ohshima Island, Tokuno-shima Island and Okinawa-jima Island,
Japan. This animal is endangered as a result of deforestation, predation by introduced
carnivores and mortality caused by vehicles. We performed theriogenological examinations
of 32 male and 25 female Ryukyu long-furred rats carcasses collected from wild populations
on northern Okinawa-jima Island from December 2005 to September 2013. Adult males had
remarkably large preputial glands. Seminiferous diameter of adult was significantly small
(136 ± 28 µm, n=8) from April to August. Numerous spermatozoa were
observed from September through February, and seminiferous diameter was significantly
large (216 ± 27 µm, n=12) during this time in adults; testes length
changed in a similar pattern. These findings indicate that the mating season may occur
from September through February. Size (body length) at sexual maturity was estimated to be
>560 mm in both sexes. From observation of corpora lutea and placental scars, litter
size was estimated to range from 2 to 12 (average=6, n=4). These results provide
fundamental knowledge that will be beneficial for in situ and ex
situ conservation of this rare species. 相似文献
9.
Fumie MAGATA Yoshikazu ISHIDA Akio MIYAMOTO Hidefumi FURUOKA Hisashi INOKUMA Takashi SHIMIZU 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(1):81-84
We investigated the
concentration of the bacterial endotoxin lipopolysaccharide (LPS) in the blood, ovarian
follicular fluid and uterine fluid of a clinical case of bovine metritis. A 2-year-old
lactating Holstein cow exhibited continuous fever >39.5°C for more than 2 weeks after
normal calving. The cow produced a fetid, watery, red-brown uterine discharge from the
vagina and was diagnosed with metritis. The LPS concentrations in plasma and uterine fluid
were 0.94 and 6.34 endotoxin units (EU)/ml, respectively. One of seven
follicles showed an extremely high level of LPS (12.40 EU/ml) compared to
the other follicles (0.62–0.97 EU/ml). These results might suggest the
presence of high concentration of LPS in follicles in cows with postpartum metritis. 相似文献
10.
Shuhei ENJOJI Ryotaro YABE Nobuyuki FUJIWARA Shunya TSUJI Michael P. VITEK Takuya MIZUNO Takayuki NAKAGAWA Tatsuya USUI Takashi OHAMA Koichi SATO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1451-1456
Canine melanoma is one of the most important diseases in small animal medicine.
Protein phosphatase 2A (PP2A), a well conserved serine/threonine phosphatase, plays a
critical role as a tumor suppressor. SET/I2PP2A is an endogenous inhibitor for PP2A, which
directly binds to PP2A and suppresses its phosphatase activity. Elevated SET protein
levels have been reported to exacerbate human tumor progression. The role of SET in canine
melanoma, however, has not been understood. Here, we investigated the potential
therapeutic role for SET inhibitors in canine melanoma. The expression of SET protein was
observed in 6 canine melanoma cell lines. We used CMeC-1 cells (primary origin) and CMeC-2
cells (metastatic origin) to generate cell lines stably expressing SET-targeting shRNAs.
Knockdown of SET expression in CMeC-2, but not in CMeC-1, leads to decreased cell
proliferation, invasion and colony formation. Phosphorylation level of p70 S6 kinase was
decreased by SET knockdown in CMeC-2, suggesting the involvement of mTOR (mammalian target
of rapamycin)/p70 S6 kinase signaling. The SET inhibitors, OP449 and FTY720, more
effectively killed CMeC-2 than CMeC-1. We observed PP2A activation in CMeC-2 treated with
OP449 and FTY720. These results demonstrated the potential therapeutic application of SET
inhibitors for canine melanoma. 相似文献