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1.
Direction-dependence, or anisotropy, of spatial distribution patterns of vegetation is rarely explored due to neglect of this ecological phenomenon and the paucity of methods dealing with this issue. This paper proposes a new approach to anisotropy analysis of spatial distribution patterns of plant populations on the basis of the data resampling technique (DRT) combined with Ripley’s L index. Using the ArcView Geographic Information System (GIS) platform, a case study was carried out by selecting the population of Pinus massoniana from a needle-and broad-leaved mixed forest community in the Heishiding Nature Reserve, Guangdong Province. Results showed that the spatial pattern of the P. massoniana population was typically anisotropic with different patterns in different directions. The DRT was found to be an effective approach to the anisotropy analysis of spatial patterns of plant populations. By employing resampling sub-datasets from the original dataset in different directions, we could overcome the difficulty in the direct use of current non-angular methods of pattern analysis. Translated from Acta Scientialrum Naturalium Universitatis Sunyatseni, 2006, 45(2): 83–87 [译自: 中山大学学报 (自然科学版)]  相似文献   

2.
The vegetation pattern in the upstream of Minjiang River, and its relationship with environment factors, such as landscape position (elevation, slope, aspect), precipitation and temperature and soil are analyzed in this paper. The data used in this paper were based on the landscape map derived from 1994 TM imagery. The results were as follows: 1) dominant landscape types were forest, shrub land and grassland, which were very similar in terms of area ratio (32.87%, 31.85% and 28.44%, respectively); 2) the patch shape of conifer forest and mixed forest was complicated while that of broad-leaved forest and cultivated land was simple; 3) the fragmentation of conifer forest and mixed forest was serious in contrast with low fragmentation of broad-leaved forest and cultivated land; and 4) closed scrub and grassland had a high contagion and good connectivity while mixed forest had a lower contagion and bad connectivity. In addition, the vegetation distribution pattern of upstream of Minjiang River was closely related with elevation and temperature, but the relationship between vegetation and precipitation was not statistically significant. __________ Translated from Journal of Beijing Normal University (Natural Science), 2005,41(4) [译自: 北京师范大学学报(自然科学版), 2005,41(4)]  相似文献   

3.
The home ranges of the Narcissus Flycatcher (Ficedula narcissina elisae) and the Yellow-rumped Flycatcher (F. zanthopygia) are measured by radio telemetry in a subalpine forest near Beijing, China. The home range is calculated by 100% Minimum Convex Polygon (MCP), and the area varies from 2,000 to 5,000 m2. The majority of flycatchers can be found in the bottom of valleys and the underside of mountains. It is fairly rare for both Flycatcher species to leave their nests more than 70 m. Individuals of the species in pair-banding and nest-detecting periods have larger home ranges than those in incubation and rearing periods. The levels of canopy coverage in the home ranges of Narcissus Flycatchers are significantly higher than that of Yellow-rumped Flycatchers. There are also more tall trees and stumps in the home ranges of Narcissus Flycatchers than in that of Yellow-rumped Flycatchers. The dominant tree species in the home ranges of Narcissus Flycatchers is Dahurian Birch (Betula dahurica), whereas Manchurian Walnut (Juglans mandshurica) is the dominant tree species in the home ranges of Yellow-rumped Flycatchers. Translated from Journal of Beijing Normal University (Natural Science), 2006, 42(3): 295–299 [译自: 北京师范大学学报 (自然科学版)]  相似文献   

4.
Seven alkaloids were isolated from the seeds of Ammopiptanthus mongolica by thin layer chromatography and silica gel column chromatography, and the chemical structures of five alkaloids, 17-oxosparteine, β-isosparteine, 3α-hydroxysparteine, sparteine, and 3β-hydroxysparteine were identified by 1H nuclear magnetic resonance (NMR) and electron ionization mass spectrum (EIMS). __________ Translated from Journal of Lanzhou University (Natural Sciences), 2007, 43(2): 43–46 [译自: 兰州大学学报(自然科学版)]  相似文献   

5.
Proteins are fundamental components of all living cells and the protein-protein interaction plays an important role in vital movement. This paper briefly introduced the original Resonant Recognition Model (RRM), and then modified it by using the wavelet transform to acquire the Modified Resonant Recognition Model (MRRM). The key characteristic of the new model is that it can predict directly the protein-protein interaction from the primary sequence, and the MRRM is more suitable than the RRM for this prediction. The results of numerical experiments show that the MRRM is effective for predicting the protein-protein interaction. Translated from Journal of Shanghai University (Natural Science), 2006, 12(1): 69–73 [译自: 上海大学学报(自然科学版)]  相似文献   

6.
This paper is based on the fieldwork in Xishuangbanna Natioanl Nature Reserve in Yunnan Province of China. GPS data of Asian elephants were collected and analyzed with the remote sensing satellite photos of the region to estimate the landform physiognomy of different colors. We also analyzed a series of ecological factors including altitude, landform, relief, villages and roads which affected the distribution and movement of Asian elephants. The results suggested the possibility of designing and establishing corridors in Xishuangbanna National Nature Reserve to protect the population of wild elephants in the region. __________ Translated from Journal of Beijing Normal University (Natural Science) 2006, 42(4): 405-C409 [译自: 北京师范大学学报 (自然科学版)]  相似文献   

7.
8.
By inducing and amplifying dendritic cells (DCs) derived from the bone marrow of asthma murine in vitro, cytokines mRNA were expressed, and the functions of DCs were investigated. Cells isolated from murine bone marrow have been cultured with rmGM-CSF and rmIL-4, and the expression of cytokines mRNA was determined by ribonuclease protection assay combined with multi-probe templates. Large numbers of DCs have been obtained from bone marrow, and they expressed interleukin-13 (IL-13), interleukin-9 (IL-9), and interleukin-3 (IL-3) mRNA. Moreover, the level of IL-13 mRNA and IL-9 mRNA expressed by DCs in asthmatic mice was significantly higher than those in the control groups (P<0.05). But, the level of IL-3 mRNA showed no discrepancy between the two groups (P>0.05). DCs are very important in the forming and developing of asthma, which implies that the therapy targeted at DCs will possibly become a new goal. __________ Translated from Journal of Nanjing Normal University (Natural Science), 2005, 28(2): 96–100 [译自: 南京师范大学学报 (自然科学版), 2005, 28(2): 96–100]  相似文献   

9.
Pressure-volume curve (PV curve) technique is a major method for studying critical plant water potential and critical tissue water content when plasmolysis takes place. In the present study, a mathematical solution method is put forward to obtain parameters based on the PV curve. The calculated results for the parameters of Lolium perenne, Festuca arundinacea, Leymus chinensis and Stipa krylovii indicated that the mathematical solution method is convenient for actual research compared with the graphical method. Further analysis of the calculations suggested that drought resistance decreased in the following order: S. krylovii > F. arundinacea and L. chinensis > L. perenne. __________ Translated from Acta Scientiarum Naturalium Universitatis Nankaiensis, 2006, 39(3): 16–22 [译自: 南开大学学报 (自然科学版)]  相似文献   

10.
Dibenzothiophene (DBT) monooxygenase (DszC) catalysis, the first and also the key step in the microbial DBT desulfurization, is the conversion of DBT to DBT sulfone (DBTO2). In this study, dszC of a DBT-desulfurizing bacterium Rhodococcus sp. DS-3 was cloned by PCR. The sequence cloned was 99% homologous to Rhodococcus erythropolis IGTS8 that was reported in the Genebank. The gene dszC could be overexpressed effectively after being inserted into plasmid pET28a and transformed into E. coli BL21 strain. The expression amount of DszC was about 20% of total supernatant at low temperature. The soluble DszC in the supernatant was purified by Ni2+ chelating His-Tag resin column and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to electronics purity. Only one band was detected by Western-blotting, which is for the antibody released in mouse against purified DszC in the expression product of BL21 (DE3, paC5) and Rhodococcus sp. DS-3. The activity of purified DszC was 0.36 U. DszC can utilize the organic compound such as DBT and methyl-DBT, but not DBT derivates such as DBF, which has no sulfur or inorganic sulfur. __________ Translated from Acta Scientiarum Naturalium Universitatis Nankaiensis, 2005, 38(6): 1–6 [译自: 南开大学学报 (自然科学版), 2005, 38(6): 1–6]  相似文献   

11.
Acute-phase response is documented to be a significant mechanism of innate immunity in vertebrates and invertebrates. In this study, proteomic methodologies were applied for different protein expressions in hemolymph of Scylla serrata challenged by Vibrio parahaemolyticus after immunization, and in muscles of the crabs separately challenged by V. parahaemolyticus, V. anguillarum and Aeromonas hydrophila. Up-regulated cryptocyanin is documented in the hemolymph and up-regulated calexcitin, wingless (fragment) and tachykinin-related peptide in the muscle as acute-phase proteins. All the four altered proteins were responsible for bacterial stress, but cryptocyanin seemed to be a memory response protein against the challenge by a live bacterium after immunization of the live cells. These up-regulated proteins can be indicative of an understanding of immunity of a crab. __________ Translated from Journal of Xiamen University (Natural Science), 2005, 44(4): 559–562, 44(Sup.): 191–194 [译自: 厦门大学学报(自然科学版), 2005, 44(4): 559–562, 44(增刊): 191–194]  相似文献   

12.
Abstract We evaluated the inhibitory effect of 3,7-dinitrodibenzobromonium salts (cBr) on the proliferation of human chronic myelogenous leukemia K562 cell by trypan blue exclusion test and MTT colorimetric assay. The degree of DNA damage in K562 cells treated with cBr, was detected by isotopic tracer method (3H-TdR). The morphological changes of these K562 cells were examined by fluorescence and electron microscopy. Biochemical characteristics of K562 cells were detected by flow cytometry and 3H-thymidine incorporation assay. Findings indicated that cBr could significantly inhibit cell proliferation and result in DNA damage of K562 cells. cBr is a new type of immunostimulant and can induce cell apoptosis. __________ Translated from Journal of Lanzhou University (Natural Sciences), 2006, 42(6): 49–61 [译自: 兰州大学学报(自然科学版)]  相似文献   

13.
The amplified fragment length polymorphic (AFLP) technique was used to analyze the genome DNA polymorphism among 8 breeds of domestic ducks and 2 species of wild ducks. Nine of the 17 selected primers pairs gave reproducible polymorphic DNA amplification bands. The amplified bands ranged from 44 to 83 per primer pair. Of the 513 AFLP markers obtained, 498 were polymorphic. The proportion of polymorphic loci was 97.1%. The genetic distance (D) and similarity coefficients (GS) were calculated based on the polymorphic data. Between domestic ducks D ranged from 0.331 to 0.589, while between domestic ducks and the wild ducks, it ranged from 0.298 to 0.520 (vs. Anas Platyrhynchos) and from 0.316 to 0.522 (vs. A. Poecilorhyncha), respectively. The variance analysis showed no significant difference between the two groups of data, which indicated that both mallard and spot-billed ducks made contributions to domestic duck evolution. A dendrogram was constructed according to the D value. __________ Translated from Journal of Xiamen University (Natural Science), 2005, 44(5): 729–733 [译自: 厦门大学学报 (自然科学版), 2005, 44(5): 729–733]  相似文献   

14.
One hundred and thirty-eight echolocation calls of 63 free-flying individuals of five bat species (Rhinolophus ferrumequinum, Myotis formosus, Myotis ikonnikovi, Myotis daubentoni and Murina leucogaster) were recorded (by ultrasonic bat detector (D980)) in Zhi’an village of Jilin Province, China. According to the frequency-time spectra, these calls were categorized into two types: FM/CF (constant frequency) / FM (R. ferrumequinum) and FM (frequency modulated) (M. formosus, M. ikonnikovi, M. daubentoni and M. leucogaster). Sonograms of the calls of R. ferrumequinum could easily be distinguished from those of the other four species. For the calls of the remaining four species, six echolocation call parameters, including starting frequency, ending frequency, peak frequency duration, longest inter-pulse interval and shortest inter-pulse interval, were examined by stepwise discriminant analysis. The results show that 84.1% of calls were correctly classified, which indicates that these parameters of echolocation calls play an important role in identifying bat species. These parameters can be used to test the accuracy of general predictions based on bats’ morphology in the same forest and can provide essential information for assessing patterns of bat habitat use. __________ Translated from Journal of Northeast Normal University (Natural Science Edition), 2006, 38 (3): 109–114 [译自: 东北师范大学学报(自然科学版)]  相似文献   

15.
An Arabidopsis thaliana male sterile mutant EC2-157 has been isolated using an EMS mutagenesis strategy. Genetic analysis indicated that it was controlled by a single recessive gene called ms157. No pollen grains have been observed in mutant anthers. ms157 Has been mapped to a region of 74kb located in BAC clone T6K22 on chromosome IV using a map-based cloning strategy. As no male sterile genes have been reported in this region, ms157 could be a novel gene related to fertility. The further molecular cloning and functional analysis on this gene should facilitate our understanding of A. thaliana another development. __________ Translated from Journal of Shanghai Normal University (Natural Sciences), 2005, 34(1): 58–63 [译自: 上海师范大学学报 (自然科学版), 2005, 34(1): 58–63]  相似文献   

16.
After 20 years of dedicated research, Jiafuzhan has been successfully developed under the new technologies in breeding high-quality early indica rice cultivars. Its rice quality has almost reached the A-level Editable Rice of Agriculture Department of China, and its average production reaches 400–500 kg/(666.7 m2). This new cultivar also has other characteristics such as enhanced resistance of blast and fallen, steady productivity, and strong adaptability. Jiafuzhan has been put into production of over 11.4 × 104 hm2 in Fujian Province and has been introduced and extended in other Provinces like Jiangxi, Guangdong, and Guangxi, China. The successes of breeding Jiafuzhan is a solution to the existing perennial problems in the rice industry, such as poor grain quality of big-grain rice and early indica rice, low productivity, and poor blast resistance of elite rice. __________ Translated from Journal of Xiamen University (Natural Science), 2006, 45(1): 114–119 [译自: 厦门大学学报 (自然科学版)]  相似文献   

17.
Recent collections from six sections in Lanongla area, Tethyan Himalaya allow the establishment of four buchia assemblages. In ascending order, they are Buchia-Buchia spitiensis, Buchia masquensis-Buchia rugasa, Buchia blanfordiana, Buchia piochii and Buchia subokensis assemblages. These Buchia assemblages first demonstrate that not only the Upper Jurassic strata but also the highest Buchia assemblage-Buchia subokensis, which appeared in Lower Cretaceous strata all over the world are present in Lanongla area. This first records the highest Buchia assemblage in Lanongla area. __________ Translated from Acta Scientiarum Naturalium Universitatis Pekinensis, 2005, 41 (4) [译自: 北京大学学报( 自然科学版), 2005,41(4)]  相似文献   

18.
Five ethanolic extracts from the mycelia of Ganoderma lucidum, G. tsugae, G. oerstedii, G. subamboinense, and G. resinaceum were respectively studied on their anticancerous activities against leukemic HL-60 cell line in vitro. Results showed that all five extracts potently inhibited HL-60 proliferation. The extract from G. lucidum mycelia exerted the highest activity. Annexin V/PI bivariate flow cytometric analysis further revealed that the five extracts significantly induced early apoptosis in HL-60 cells. The results illustrate that not only G. lucidum but also other Ganoderma species can inhibit cancer cells, and their mechanisms are related to induction of apoptosis. __________ Translated from Journal of Shanghai Normal University (Natural Sciences), 2005, 34(2): 77–81 [译自: 上海师范大学学报 (自然科学版), 2005, 34(2): 77–81]  相似文献   

19.
There are five wild populations of Cycas fairylakea in Guangdong Province, China, three of which are newly found. A study of the biological characteristics of C. fairylakea populations showed that this species had a narrow colonization area within 300 hm2, and an island pattern of distribution. Because of the overexploitation, urbanization, environment pollution, plant diseases, and insect pests, the wild populations and individuals of C. fairylakea decreased markedly in the past decades. All five populations have an opposite pyramid age structure, few coning plants, few seed production, and low level of seed germination rate or sterility. In conclusion, C. fairylakea in Guangdong Province was threatened seriously and an urgent need to take effective efforts to protect the plants and habitats in its location sites was required. __________ Translated from Acta Scientiarum Naturalium Universitatis Sunyatseni, 2005, 44(6): 97–100 [译自: 中山大学学报 (自然科学版), 2006, 44(6): 97–100]  相似文献   

20.
Based on Remote Sensing (RS), Geographical Information Systems (GIS), and the Spatial Principal Component Analysis (SPCA) method, the integrated assessment and changes in the ecological environment of Daning River Watershed are studied in this paper. The watershed is located in the Three Gorge Area in China. The result of the integrated assessment showed that level 9 had the biggest proportion in the year 1990, which was about 40%. In the year 2000, however, there were no levels with a proportion significantly bigger than the others. By comparing the assessment results in 1990 and 2000, it is discovered that the ecological environment in Daning River Watershed in 1990 was better than that in 2000. __________ Translated from Journal of Beijing Normal University (Natural Science), 2006, 42(2): 200–203 [译自: 北京师范大学学报 (自然科学版)]  相似文献   

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