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211.
Carbon fluxes and their response to environmental variables in a Dahurian larch forest ecosystem in northeast China 总被引:1,自引:0,他引:1
WANG Hui-min SAIGUSA Nobuko ZU Yuan-gang WANG Wen-jie YAMAMOTO Susumu KONDO Hiroaki 《林业研究》2008,19(1):1-10
The Dahurian larch forest in northeast China is important due to its vastness and location within a transitional zone from boreal to temperate and at the southern distribution edge of the vast Siberian larch forest. The continuous carbon fluxes were measured from May 2004 to April 2005 in the Dahurian larch forest in Northeast China using an eddy covariance method. The results showed that the ecosystem released carbon in the dormant season from mid-October 2004 to April 2005, while it assimilated CO2 from the atmosphere in the growing season from May to September 2004. The net carbon sequestration reached its peak of 112 g.m^-2.month ^-1 in June 2004 (simplified expression of g (carbon).m^-2.month^-1) and then gradually decreased. Annually, the larch forest was a carbon sink that sequestered carbon of 146 g-m^-2.a^-1 (simplified expression of g (carbon).m^-2.a^-1) during the measurements. The photosynthetic process of the larch forest ecosystem was largely affected by the vapor pressure deficit (VPD) and temperature. Under humid conditions (VPD 〈 1.0 kPa), the gross ecosystem production (GEP) increased with increasing temperature. But the net ecosystem production (NEP) showed almost no change with increasing temperature because the increment of GEP was counterbalanced by that of the ecosystem respiration. Under a dry environment (VPD 〉 1.0 kPa), the GEP decreased with the increasing VPD at a rate of 3.0 μmol.m^-2.s^-1kPa -1 and the ecosystem respiration was also enhanced simultaneously due to the increase of air temperature, which was linearly correlated with the VPD. As a result, the net ecosystem carbon sequestration rapidly decreased with the increasing VPD at a rate of 5.2 μmol.m^-2.s-1.kPa^-1. Under humid conditions (VPD 〈 1.0 kPa), both the GEP and NEP were obviously restricted by the low air temperature but were insensitive to the high temperature because the observed high temperature value comes within the category of the optimum range. 相似文献
212.
Summary When a local slow bolting variety Osaka Shirona Bansei (Brassica rapa L. ssp. pekinensis, syn. B. campestris L. ssp. pekinensis) was grown in a phytotron (25°C, 16 hours day length without chilling treatment), one third of the plants bolted and flowered. In order to clarify the different flowering responses in the variety, a progeny line (FNC) of the flowering plants was chilled for 4 different periods (0, 22, 36 and 53 days) in a chamber of 2 7°C, then transplanted to three different conditions, i.e. PHY: 25–20°C day and night temperatures, 16 hours day length, GHL: 10 25°C, 16 hours day length with supplementary light and GHN: 10 25°C, natural day length (10 15 hours). In PHY, FNC bolted and flowered with almost the same leaf numbers in all 4 different chilling treatments. This means that FNC has very low sensitivity and no requirement to low temperature for its reproductive growth. In GHN (short day length), FNC bolted very slowly. Then the bolting and flowering of FNC were promoted by both long day length and high temperature. The newly found bolting characteristics of Osaka Shirona Bansei could be applied to breed unique slow bolting Chinese cabbage (B. rapa L. ssp. pekinensis) which might be non-sensitive to low temperature and its bolting and flowering would be induced with the combination of long day length and high temperature. Using the unique variety, it might be also possible to establish a new cropping type of Chinese cabbage (late autumn sowing, spring harvest).Abbreviations PHY
Phytotron, long day and high temperature condition
- GHL
Greenhouse, long day and medium temperature condition
- GHN
Greenhouse, natural (short) day and medium temperature condition
- FNC
A progeny line of Osaka Shirona Bansei which flowered with no chilling treatment
- FC
A progeny line of Osaka Shirona Bansei which flowered with chilling treatment 相似文献
213.
Katayama M Nishijima N Okamura Y Katayama R Yamashita T Kamishina H Uzuka Y 《Journal of Feline Medicine and Surgery》2012,14(4):257-261
Clarithromycin (CLM) has been known to increase the cyclosporine (CsA) trough levels in human transplant patients. However, the interaction of CLM with CsA has not been reported in cats. In this study, the effects of oral dosing of CLM on the pharmacokinetics and dosing of CsA in cats were investigated. Co-administration of CLM with CsA resulted in significant increases of oral bioavailability of CsA. In addition, CLM reduced the CsA dosage required to maintain the therapeutic CsA trough levels to almost 35% of the initial CsA therapy and the dose frequency was successfully replaced from a twice a day schedule to once a day in a feline kidney transplant patient. The addition of CLM to the regular CsA-based immunosuppression could be used as an effective alternative to classical ketoconazole treatment in feline kidney transplant patients and may result in substantial cost saving and convenience for the cat owners. 相似文献
214.
215.
Hiroshi Hayakawa Maiko Akasaka Yoshiko Shimono Shunji Kurokawa Tomoko Nishida Hiroaki Ikeda Toru Wakamatsu 《Weed Biology and Management》2014,14(4):251-261
Nucleotide sequence variations were investigated with respect to the geographical distribution patterns of Miscanthus sinensis populations that were sampled from 26 Japanese national parks and three populations of the Ryukyu Islands. Twelve homozygous sequences in the nuclear ribosomal DNA internal transcribed spacer region were detected. The populations of M. sinensis in mainland Japan mainly were composed of a monophyletic group with a symapomorphic character, whereas those in the Ryukyu Islands included a polyphyletic group. Only an internal transcribed spacer haplotype with a plesiomorphic character was found in both mainland Japan and the Ryukyu Islands. Thus, no clear geographical isolation was observed in this species. These facts might be caused by the ability of M. sinensis as a pioneer plant to have a high migration potential and high gene flow by outcrossing. On the basis of the results of this study (nuclear ribosomal DNA) and the previous study (chloroplast DNA), a phylogeographical history of M. sinensis was presumed where the ancestral and derived lineages were distributed in the southern and northern regions of Japan, respectively, without strict geographical isolation. 相似文献
216.
217.
Measurement of myelin basic protein in the cerebrospinal fluid of dogs with degenerative myelopathy 总被引:2,自引:0,他引:2
Oji T Kamishina H Cheeseman JA Clemmons RM 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2007,36(3):281-284
BACKGROUND: Analysis of cerebrospinal fluid (CSF) is part of a routine clinical workup in veterinary patients when neurologic disease is suspected. However, knowledge of particular protein markers of disease in CSF is limited. The concentration of myelin basic protein (MBP) in CSF is used as a biochemical marker in humans to evaluate demyelinating lesions in the central nervous system (CNS). OBJECTIVE: The purpose of this study was to evaluate an ELISA for determination of MBP concentration in the CSF of German shepherd dogs with degenerative myelopathy (GSDM). METHODS: Cross-reactivity of the anti-human polyclonal antibody used in a commercial ELISA (Active MBP ELISA, Diagnostic Systems Laboratories Inc, Webster, TX, USA) was tested with canine MBP by immunoblotting. CSF samples were collected from both the cisterna magna and the lumbar cistern of 8 clinically healthy control dogs and 8 German shepherd dogs clinically diagnosed with GSDM. MBP concentrations were measured in all CSF samples using the ELISA. RESULTS: The mean MBP concentration in CSF from the lumbar cistern of dogs with GSDM (3.13 -/+ 0.46 ng/mL) was significantly higher than that in the cisterna magna (0.70 -/+ 0.06 ng/mL) and from both cisternal (0.47 -/+ 0.07 ng/mL) and lumbar (0.94 -/+ 0.37 ng/mL) samples from control dogs. CONCLUSION: The MBP ELISA has potential as a supplemental test of CSF to diagnose demyelinating disorders in dogs. 相似文献
218.
Wang Qunhui Narita Jun-ya Ren Nanqi Fukushima Toshifumi Ohsumi Yukihide Kusano Kohji Shirai Yoshihito Ogawa Hiroaki I. 《Water, air, and soil pollution》2003,144(1-4):405-418
Interest in the production of lactic acid (LA) is increasing inrelation to its applications in the synthesis of biodegradablepolymer materials. Before kitchen waste is used as substrates inLA fermentation, it must be stored for some days in the wastecollection system. This study examined the effects of pHadjustment including initial pH before the storage in terms of thekind and the amount of added acid on preservation of the waste. The optical purity of LA generated during the storage was alsoanalyzed. It was found that antibacterial activity andsuppression ability to D-lactic acid (D-LA) were stronger in theorder: acetic acid > L-lactic acid (L-LA) > hydrochloric acid ≈ nitric acid. The optimum condition of waste storage was found to be adjusting initial pH to 3.4 by adding acetic acid. It can be expected that preservation of kitchen waste can be realized by inhibiting the growth of putrefactive bacteria, and higher optical purity of L-LA was obtained by adding weak acid to the waste. 相似文献
219.
Xi Liang Kyota Yamazaki Mohammad Kamruzzaman Xue Bi Arvinda Panthee Hiroaki Sano 《畜牧与生物技术杂志(英文版)》2014,(3):325-332
Background: The use of antibiotics in animal diets is facing negative feedback due to the hidden danger of drug residues to human health. Traditional Chinese herbal medicine has been used to replace antibiotics in the past two decades and played an increasingly important role in livestock production. The present study was carried out to assess the feeding effects of a traditional nourishing Chinese herbal medicine mixture on kinetics of plasma glucose, protein and energy metabolism in sheep. Ruminal fermentation characteristics were also determined. Methods: Four sheep were fed on either mixed hay (MH-diet) or MH-diet supplemented with 2% of Chinese herbal medicine (mixture of Astragalus root, Angelica root and Atractylodes rhizome; CHM-diet) over two 3S-day periods using a crossover design. The turnover rate of plasma glucose was measured with an isotope dilution method using [U-^13C]glucose. The rates of plasma leucine turnover and leucine oxidation, whole body protein synthesis (WBPS) and metabolic heat production were measured using the [1-^13C]leucine dilution and open circuit calorimetry. Results: Body weight gain of sheep was higher (P = 0.03) for CHM-diet than for MH-diet. Rumen pH was lower (P = 0.02), concentration of rumen total volatile fatty acid tended to be higher (P = 0.05) and acetate was higher (P = 0.04) for CHM-diet than for MH-diet. Turnover rates of plasma glucose and leucine did not differ between diets. Oxidation rate of leucine tended to be higher (P = 0.06) for CHM-diet than for MH-diet, but the WBPS did not differ between diets. Metabolic heat production tended to be greater (P = 0.05) for CHM-diet than for MH-diet. Conclusions: The sheep fed on CHM-diet had a higher body weight gain and showed positive impacts on rumen fermentation and energy metabolism without resulting in any adverse response. Therefore, these results suggested that the Chinese herbal medicine mixture should be considered as a potential feed additive for sheep. 相似文献
220.