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1.
G protein-coupled receptor (GPR) 120 is an unsaturated fatty acid receptor, which is associated with various physiological functions. It is reported that the genetic variant of GPR120, p.Arg270His, is detected more in obese people, and this genetic variation functionally relates to obesity in humans. Obesity is a common nutritional disorder also in dogs, but the genetic factors have not ever been identified in dogs. In this study, we investigated the molecular structure of canine GPR120 and searched for candidate genetic variants which may relate to obesity in dogs. Canine GPR120 was highly homologous to those of other species, and seven transmembrane domains and two N-glycosylation sites were conserved. GPR120 mRNA was expressed in lung, jejunum, ileum, colon, hypothalamus, hippocampus, spinal cord, bone marrow, dermis and white adipose tissues in dogs, as those in mice and humans. Genetic variants of GPR120 were explored in client-owned 141 dogs, resulting in that 5 synonymous and 4 non-synonymous variants were found. The variant c.595C>A (p.Pro199Thr) was found in 40 dogs, and the gene frequency was significantly higher in dogs with higher body condition scores, i.e. 0.320 in BCS4–5 dogs, 0.175 in BCS3 dogs and 0.000 in BCS2 dogs. We conclude that c.595C>A (p.Pro199Thr) is a candidate variant relating to obesity, which may be helpful for nutritional management of dogs.  相似文献   
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The populations of red alga Gelidium elegans along the coast of Miyakejima Island were severely damaged by a volcanic eruption in 2000. The effect of this volcanic eruption has been long lasting, and populations of this red alga still have not recovered. We investigated the effect of seabed sediment particles derived from volcanic ash on the substrate adhesion of G.?elegans spores. The analysis provides evidence that increasing amounts of sediment particles result in lower adhesion rates of G.?elegans spores, and that smaller sediment particles have a greater influence on adhesion. The amount of seabed sediment particles around Miyakejima Island was 9.3?C1815.4?mg/cm2. This amount has changed greatly from year to year. The adhesion rate of G.?elegans spores in water around Miyakejima Island was 0?% at all points in 2008 and 2010, but it was estimated as 6.3?C38.6?% in 2009. These results suggest that there is significant inhibition of algal spore adhesion by seabed sediment particles derived from volcanic ash around Miyakejima Island.  相似文献   
4.
Although allometric equations can be used to accurately estimate biomass and/or carbon stock in forest ecosystems, few have been developed for logged-over tropical rainforests in Southeast Asia. We developed allometric relationships between tree size variables (stem diameter at breast height (dbh) and tree height) and leaf, branch, stem and total above-ground biomass in two logged-over tropical rainforests with different soil conditions in Sarawak, Malaysia. The study sites were originally classified as mainly lowland dipterocarp forest and have been selectively logged in the past 20 years. In total, 30 individuals from 27 species were harvested to measure above-ground parts. The correlation coefficients for the allometric relationships obtained for total above-ground biomass as a function of dbh had high values (0.99), although the relationships for leaf biomass had a relatively low coefficient (0.83). We also found relatively high coefficients for allometric relationships between tree height and plant-part biomass, ranging from 0.82 to 0.97. Moreover, there were no differences for allometric equations of total above-ground biomass between study sites. A comparison of equations of above-ground biomass in various previously reported tropical rainforests and pan-tropic general equations imply that our allometric equations differ largely from the equations for tropical primary forests, early successional secondary forest, and even for the general models. Therefore, choosing the biomass estimation models for above-ground biomass in the logged-over forests of Southeast Asia requires careful consideration of their suitability.  相似文献   
5.
The causes of soil alkalinization in the Songnen Plain of Northeast China   总被引:2,自引:0,他引:2  
The causes of soil alkalinization in the Songnen Plain of Northeast China were mainly analyzed from two aspects, natural and anthropogenic. Natural factors of alkalinization are parent materials, topographic positions, freeze-thaw action, wind conveyance, water properties and semi-arid/sub-humid climate. Some of them were always being neglected, such as freeze-thaw action and wind conveyance. Anthropogenic causes are mainly population pressure, overgrazing and improper agricultural and economic policies. In recent decades, overgrazing played a main role in secondary soil alkalinization, which led to the decline of Leymus chinensis grasslands. Now, the alkalinization is very severe, and more than 3.2 × 106 ha area has been affected by salt, which becomes one of the three largest sodic–saline areas in the world.  相似文献   
6.
We evaluated the acute toxicity of the antifouling biocide Sea-Nine 211 to the algae Chaetoceros calcitrans, Dunaliella tertiolecta, Tetraselmis tetrathele, and Skeletonema costatum, the crustacea Tigriopus japonicus and Portunus trituberculatus, and the polychaete Perinereis nuntia. The algae, and especially the diatoms C. calcitrans and S. costatum, were sensitive to Sea-Nine 211 toxicity, with the average acute toxicity values being 0.32, 3.9, 1.6, 0.22, 1.6, 12, and 27 μg/l for C. calcitrans, D. tertiolecta, T. tetrathele, S. costatum, T. japonicus, P. trituberculatus, and P. nuntia, respectively. A sediment toxicity test for Sea-Nine 211 using the polychaete P. nuntia revealed demonstrated that the 14-day median lethal concentration was 110 μg/kg dry-wt sediment and that growth was the most sensitive indicator. The chronic toxicity values of Sea-Nine 211 for the diatoms C. calcitrans and S. costatum were within the range of reported Sea-Nine 211 concentrations in seawater in coastal Japan, and the toxicity values for P. nuntia were within the reported concentrations in sediment. Based on these results, Sea-Nine 211 may have toxic effects on some sensitive species residing in the coastal areas of Japan, but the ecological risk posed by Sea-Nine 211 would appear to be confined to a limited area of Japanese coastal waters.  相似文献   
7.
Grassland is one of the most important terrestrial ecosystems for carbon (C) and nitrogen (N) cycling. However, while CO2 fixation by phototrophic bacteria is relatively well studied, little is known about microbial CO2 fixation without light by chemoautotrophic bacteria in grassland soils. Therefore, in this study, the isotope 14C-CO2 was used to investigate the CO2-fixing process in grassland soils. Soil samples were collected from both fenced and adjacent continuous grazing grassland sites in Inner Mongolia and then incubated for 120 days under dark conditions. Meanwhile, the cbbL genes (red- and green-like) were analyzed to isolate chemoautotrophic bacteria, which are responsible for CO2 fixation. After incubation, 14C was fixed into soil organic carbon (14C-SOC) and microbial biomass carbon (14C-MBC) were found in both the fenced and grazing soils, and the fixation rate of 14C-SOC in the fenced soils (48.55‰) was significantly higher than in the grazing soils (22.11‰). The fixation rate of 14C-MBC in the fenced soils (14.05‰) was higher than in the grazing soils (7.08‰), but the difference was not significant. The red-like cbbL genes could be detected in all the soil samples, but the green-like cbbL genes could not be amplified. A greater number of identified operational taxonomic units were observed in the fenced soils compared with the grazing soils. The chemoautotrophic bacteria were mainly affiliated with Alphaproteobacteria and Actinobacteria. However, Chloroflexi was detected in only the fenced soils. The results suggested that CO2 fixation by chemoautotrophic bacteria might be significant in carbon cycling in grassland.  相似文献   
8.
Diploid gametes generated with tetraploid animals are a stepping stone to improving chromosome manipulation techniques. However, artificially induced tetraploid individuals generally die soon after hatching. Diploid gametes could be induced by in vivo cultures of tetraploid primordial germ cells (PGCs) through germ-line chimera. In the present study, characteristics of PGCs were studied in inviable tetraploid masu salmon, Oncorhynchus masou. Histological observation of tetraploid embryos revealed that the same or smaller numbers of PGCs were observed and they migrate into the genital ridges as did diploid PGCs during gonadogenesis. By whole-mount in situ hybridization using vasa messenger RNA (mRNA), 4–35 vasa-positive signals were detected in a pair of genital ridges of tetraploids. By cytological observation of genital ridge cell suspensions, several large round cells were observed, some of which extended pseudopodia. They also contained large nuclei and round granules in their cytoplasm, characteristics of PGCs. As the results suggest that inviable artificial tetraploids have PGCs, we expect to achieve diploid gamete production through surrogate propagation and tetraploid fish production.  相似文献   
9.
Abstract

Properties of sesquioxides, clay mineralogical composition, and charge characteristics of Brown Forest soils developed under beech forests in the Kinki (Ohdaigahara) and the Tohoku District (Hakkoda) were studied with special reference to their pedogenetic processes.

The Brown Forest soils in the Kinki District were characterized by the translocation of free Al, formation of Al and/or Fe-humus complexes throughout the profile, and the predominance of 2:1: 1-2:1 intergrade minerals in the subsurface horizons, whereas those in the Tohoku District were characterized by the formation of allophane and no remarkable translocation of free Al oxides. This difference in the pedogenetic processes under the same vegetation was reflected on the amounts of Al released from primary minerals in relation to the amounts of organic matter accumulated. Major distinctive characteristics included the values of the Alp/Alo, the Fep/Feo, the Alo/Ald ratios, the Sio content, and the STPT-ZPC and pH(H2O) values.

Among these the values of the Alo/Ald ratio and/or the Sio content were found to be suitable indices for the differentiation of Brown Forest soils from Andisols in Japan In addition to the criteria used to define andic soil properties.  相似文献   
10.
We reported that meat chicks have either a greater capability to acclimatize to novel environments, or a blunted hypothalamic‐pituitary‐adrenal response to novel environments compared with layer chicks in a commercial base. The present study compared the differences in behavior and plasma corticosterone concentrations under isolation‐induced stress between neonatal meat and layer Nagoya chicks which had been separated from the same population. Both types of neonatal chicks reared in groups were individually separated and their spontaneous activity and distress‐induced vocalizations were monitored for 10 min. The responses of the two types were remarkably different, with the meat chicks being less active than the layer chicks. Distress‐induced vocalizations were fewer in the meat than in the layer chicks. The meat chicks spent more time in a sleeping posture during isolation‐induced stress. Plasma corticosterone concentrations measured at the end of the test tended to be higher in the layer chicks than in meat ones, but not significantly. In conclusion, the selection of Nagoya chickens for meat and layer may have trends similar to those observed in commercial chickens in relation to stress susceptibility.  相似文献   
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