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31.
Wenjie Wang Huimei Wang Yuangang Zu Xueying Li Takayoshi Koike 《Frontiers of Forestry in China》2006,1(2):125-135
The temperature coefficient, Q
10 (fractional change in rate with a 10°C increase in temperature) describes the temperature sensitivity of soils, roots, and
stems, as well as their possible performance in global warming processes. It is also a necessary parameter for the estimation
of total CO2 efflux from each element. A number of studies have focused on Q
10 values to date; however, their conclusions are not universal and do not always agree. A review of these reported Q
10 values therefore becomes necessary and important for a global understanding of the temperature sensitivity of different forest
types and elements. The aims of our present paper are, first, to find the frequency distribution pattern of soils, roots,
and stems (branches) and compare their temperature sensitivity; then, to find the Q
10 differences between conifer and deciduous tree species and the effect of methodology on Q
10 values; finally we want to give a perspective on future Q
10-related studies. We found that most Q
10 values of each element were concentrated in a relatively narrow range despite a total data distribution over quite a wide
range. For soil respiration, the median Q
10 value was 2.74 and the center of the frequency distribution was between 2.0 and 2.5 with a percentage of 23%. Most of the
data (>80%) were within the range from 1.0 to 4.0. The median Q
10 value for root respiration was 2.40 and the center of the frequency distribution was from 2.5 to 3.0 with a percentage of
33%. Most of the results (>80%) ranged from 1.0 to 3.0. For stem respiration, the median Q
10 value was 1.91 and the frequency distribution was concentrated between 1.5 and 2.0. Over 90% of the data ranged from 1.0
to 3.0. Obvious differences in Q
10 value were found between different elements, stem < root < soil including root < soil excluding root. The differences between
woody organisms of stems, roots, and soils excluding roots were statistically significant (p<0.05), indicating that heterotrophic respiration from microorganism activity may be more sensitive to global warming. The
duration of the period with leaves slightly affects the temperature sensitivity of woody organisms since the Q
10 values for root and stem of coniferous evergreen trees did not differ significantly from deciduous trees (p>0.10). CO2 analytical methods (soda lime absorption method, IRGA (Infra-read gas analysis), and chromatograph analysis) and root separation
methods (excised root and trenched box) slightly affected the Q
10 values of soil and root respiration (p>0.10), but an in vitro measurement of stem respiration yielded a significantly higher Q
10 value than an in vivo method (p<0.05). In general, although the Q
10 values of non-photosynthetic organisms stayed within a relatively conservative range, considerable variation between and
within elements were still detectable. Accordingly, attention should be paid to the quantitative estimation of total CO2 efflux by Q
10-related models. In future studies, the biochemical factors and the environmental and biological factors controlling respiration
should be emphasized for precise estimation of total CO2 efflux. The difficulty is how to clarify the underlying mechanism for fluctuations of Q
10 values for one specific habitat and element (e.g. temperature acclimation or adaptation of Q
10 values) and then allow the Q
10 values to be more conservative for representation of temperature sensitivity in global warming processes.
__________
Translated from Acta Phytoecologica Sinica, 2005, 29(4) [译自:植物生态学报, 2005, 29 (4)] 相似文献
32.
Esters of trans-4-hydroxycinnamic acid, cis-4-hydroxycinnamic acid and trans-3,4-dihydroxycinnamic acid with long-chain alcohols (n=15-20), were isolated from the stems of Calystegia soldanella. 相似文献
33.
Ohara H Matsumoto H Ito K Iwai K Sato K 《Journal of agricultural and food chemistry》2007,55(4):1532-1535
We compared quantity and structures of food-derived gelatin hydrolysates in human blood from three sources of type I collagen in a single blind crossover study. Five healthy male volunteers ingested type I gelatin hydrolysates from fish scale, fish skin, or porcine skin after 12 h of fasting. Amounts of free form Hyp and Hyp-containing peptide were measured over a 24-h period. Hyp-containing peptides comprised approximately 30% of all detected Hyp. The total area under the concentration-time curve of the fish scale group was significantly higher than that of the porcine skin group. Pro-Hyp was a major constituent of Hyp-containing peptides. Ala-Hyp, Leu-Hyp, Ile-Hyp, Phe-Hyp, and Pro-Hyp-Gly were detected only with fish scale or fish skin gelatin hydrolysates. Ala-Hyp-Gly and Ser-Hyp-Gly were detected only with fish scale gelatin hydrolysate. The quantity and structure of Hyp-containing peptides in human blood after oral administration of gelatin hydrolysate depends on the gelatin source. 相似文献
34.
Enomoto H Li CP Morizane K Ibrahim HR Sugimoto Y Ohki S Ohtomo H Aoki T 《Journal of agricultural and food chemistry》2007,55(6):2392-2398
Beta-lactoglobulin (beta-Lg) was glycated with maltopentaose and subsequently phosphorylated by dry-heating in the presence of pyrophosphate to investigate the structural and functional properties of phosphorylated beta-Lg. The circular dichroism spectra showed that the change of the secondary structure in the beta-Lg molecule by glycation and subsequent phosphorylation was small. The differential scanning calorimetry thermograms of beta-Lg showed that the denaturation temperature of the most stable domain was only slightly affected, whereas the retinol-binding activity of beta-Lg was somewhat reduced by glycation and subsequent phosphorylation. These results indicated that the conformational changes of the beta-Lg molecule by glycation and subsequent phosphorylation were mild. The anti-beta-Lg antibody response was somewhat reduced by glycation, but significant changes were not observed by phosphorylation. Although the stability of beta-Lg against heat-induced insolubility was improved by glycation alone, it was further enhanced by phosphorylation. The calcium phosphate solubilizing ability of beta-Lg was enhanced by phosphorylation following glycation. 相似文献
35.
Fukasawa T Murashima K Matsumoto I Hosono A Ohara H Nojiri C Koga J Kubota H Kanegae M Kaminogawa S Abe K Kono T 《Journal of agricultural and food chemistry》2007,55(8):3174-3179
Prebiotic fructooligosaccharides are noted for their intestinal immunodulating effects, and the identification of markers for the effects is a matter of great concern. This study aimed to identify marker genes for physiological effects of a particular fructooligosaccharide (FOS) on a host animal and also to define the target of its function in the small intestine. DNA microarray technology was used to screen candidate marker genes, and comprehensive changes in gene expressions in the ileum of mice fed with FOS were investigated. One of the major physiological effects of FOS was intestinal immunomodulation. Marker genes were then identified for major histocompatibility complex classes I and II, interferon, and phosphatidylinositol metabolites. Also, the ileum was segmented into Peyer's patch (PP) and the other ileal organ (DeltaPP), and these were analyzed by quantitative RT-PCR method, with the result that the site for recognizing the FOS function was the DeltaPP rather than the PP. This is the first paper showing the markers for the physiological effects of FOS in the small intestine at gene expression level. Applying these marker genes would make it possible to clarify the mechanisms of how the administration of dietary FOS and associated changes in the intestinal environment are recognized by host organisms as well as how its immunomodulating effects are expressed in the body. 相似文献
36.
Larch (Larix gmelinii (Rupr.) Rupr.) cone scales are green, but little is known of their photosynthetic role in cone development or about how they differ in gas exchange characteristics from needle leaves. In contrast to leaf photosynthesis (Pleaf), we found that stomatal regulation of cone photosynthetic rate (Pcone) was marginal because the photosynthetic carbon came from internal recycling of respiratory carbon dioxide (CO2). Photosynthetic recycling of respired CO2 was confirmed by the finding that the intercellular CO2 concentration (Ci) in cone scales was much higher than ambient [CO2]; also, there was a positive correlation between Pcone and Ci, whereas Pleaf was almost constant as Ci varied. Low chlorophyll (Chl) concentration was a limiting factor for Pcone, but not for Pleaf, as indicated by the correlation between Pcone and chlorophyll concentration. Moreover, chlorophyll utilization efficiency (Psat/Chl a+b) for cone scales was lower than that for leaves. In both cones and leaves, nitrogen (N) was positively correlated with photosynthetic capacity (P), but the P/N value was much lower for cones than for leaves. For both organs, the ratio of respiration to N was broadly similar. Although mature cones have no photosynthetic capacity, Pcone of young cones was as high as 5.3 micromol m(-2) s(-1), about 1.26 times the value of Pleaf, and accounted for the refixation of 30-40% of the respiratory CO2 produced by cones, equivalent to the photosynthetic capacity of a bundle of short shoots near each cone. Thus, Pcone may be an important additional source of photosynthate for cones, given the weak assimilating capacity of leaves that are not fully expanded during cone development. 相似文献
37.
N. Fukino T. Ohara M. Sugiyama N. Kubo M. Hirai Y. Sakata S. Matsumoto 《Euphytica》2012,187(1):133-143
Plant architecture plays an important role in the yield, product quality, and cultivation practices of many crops. Branching pattern is one of the most important components in the plant architecture of melon (Cucumis melo L.). ‘Melon Chukanbohon Nou 4 Go’ (Nou-4) has a short-lateral-branching trait derived from a weedy melon, LB-1. This trait is reported to be controlled by a single recessive or incompletely dominant major gene called short lateral branching (slb). To find molecular markers for marker-assisted selection of this gene, we first constructed a linkage map using 94 F2 plants derived from a cross between Nou-4 and ‘Earl’s Favourite (Harukei-3)’, a cultivar with normal branching. We then conducted quantitative trait locus (QTL) analysis and identified two loci for short lateral branching. A major QTL in linkage group (LG) XI, at which the Nou-4 allele is associated with short lateral branching, explained 50.9 % of the phenotypic variance, with a LOD score of 12.5. We suggest that this QTL corresponds to slb because of the magnitude of its effect. Another minor QTL in LG III, at which the Harukei-3 allele is associated with short lateral branching, explained 9.9 % of the phenotypic variance, with a LOD score of 4.2. Using an independent population, we demonstrated that an SSR marker linked to the QTL in LG XI (slb) could be used to select for short lateral branching. This is the first report of mapping a gene regulating the plant architecture of melon. 相似文献
38.
Nakamura S Tsuchiya H Okahara N Nakagawa T Ohara N Yamamoto H Li TC Takeda N Ogasawara K Torii R 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(3):279-283
A serological survey of hepatitis E virus (HEV) antibody was conducted using 202 adult captive cynomolgus monkeys, who did not show any clinical signs of acute hepatitis. Out of these, 44 monkeys were sero-positive for anti-HEV IgG and all monkeys were negative for anti-HEV IgM. All positive monkeys came from either Vietnam or China, but none from the Philippines, Indonesia, or our facility. Selected 12 monkeys out of positive monkeys from Vietnam, including 9 positive and 3 negative, revealed mostly within the reference ranges for alanine aminotransferase (ALT) and asparatate aminotransferase (AST) by serum biochemistries. Their titers of anti-HEV IgG did not correlate with the concentrations of ALT and AST. Moreover, HEV-RNA could not be detected from any fecal specimens of the 12 monkeys. Thus, monkeys with anti-HEV IgG sero-positive did not seem to be source of the HEV-pollution, because 1) sero-positive monkeys did not excrete HEV-RNA from their feces, and 2) monkeys from the Philippines and Indonesia have remained to be sero-negative for anti-HEV IgG, even if the monkeys were kept in same animal room of our facility. From these results, it could be inferred that primary infection of HEV occurred in the exported countries, but not in our colony. The contamination of HEV in indoor-captive monkeys could be prevented by precise quarantine tests, including ELISA for detecting anti-HEV and RT-PCR for HEV RNA. 相似文献
39.
Maki HAYASHIDA Kousaku SOUMA Osamu HANAGATA Masayo OKAMOTO Takayoshi MASUKO 《Animal Science Journal》2012,83(3):227-231
The rumen contents were collected from 36 wild Yeso sika deer (Cervus nippon yesoensis) captured by deer culling or by hunting in the spring, summer, autumn and winter in Hokkaido, Japan. Botanical classification was conducted, and the contents of mineral (calcium (Ca), phosphorus (P), potassium (K), sodium (Na), iron (Fe), copper (Cu) and zinc (Zn)) were measured. The animals were captured around pastures or fallow field areas in the Kushiro area. The rumen contents consisted of grasses and Sasa sp. leaves regardless of the season. Leaves and bark were ingested in the spring, autumn and winter. The macro‐mineral contents in the rumen showed seasonal changes. In the summer, the Ca, K and P contents were high, and the Na content was low. There were no seasonal changes in the Fe content. The P, Na and Fe contents were higher than the animals' requirements. In a future survey, it is needed to determine the mineral contents of the food ingested by wild Yeso sika deer. 相似文献
40.
Maeda S Miyabayashi T Yamamoto JK Roberts GD Lepine AJ Clemmons RM 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(12):1373-1376
To investigate temporal dynamic changes in the synthesis of chondroitin 6-sulfate (CS6) and chondroitin 4-sulfate (CS4) in vitro, normal articular cartilage of femoral heads was harvested from three dogs. Chondrocytes were isolated and cultured in alginate microspheres for 21 days. On days 7, 14 and 21, DNA content was quantified by fluorometric assay using Hoechst 33258. On days 14 and 21, proteoglycans were extracted, and the amounts of CS6 and CS4 were quantified after chondroitinase ABC digestion using capillary electrophoresis. The DNA content and amounts of CS6 and CS4 increased during the culture period. The amounts of CS6 and CS4 divided by DNA content revealed that the synthesis of CS6 was more up-regulated than CS4. 相似文献