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Co-Occurring Plant Species of the West African Critically Endangered Aubregrinia taïensis Heine, in Côte d’Ivoire
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作者 Doudjo Noufou Ouattara Hermann Hippolyte Tro +3 位作者 Dofoungo Koné Akoua Emilia Afanvi Doh Amed Coulibaly Adama Bakayoko 《American Journal of Plant Sciences》 2023年第8期915-928,共6页
The Upper Guinea Forest is subject to heavy deforestation. In this context, many endemic and/or rare plant species are threatened with extinction. This is the case of Aubregrinia taïensis (Aubrév. & Pell... The Upper Guinea Forest is subject to heavy deforestation. In this context, many endemic and/or rare plant species are threatened with extinction. This is the case of Aubregrinia taïensis (Aubrév. & Pellegr.) Heine, a critically endangered Sapotaceae species, endemic to Côte d’Ivoire and Ghana. After 3 years of investigation in and around the Tai National Park (TNP) in the West of Côte d’Ivoire, only one individual of this species was located and no sexual reproductive organs (fruits, seeds) were observed. Woody plant species around this individual were inventoried in order to know the species that can co-occur with Aubregrinia taïensis. For that a plot of 30 m of diameter was established around the individual and all of the woody species of this circle were inventoried. Then, the taxonomic diversity, the chorology of the species, the conservation status and their life-form were recorded. A total of 130 woody plant species belonging to 51 families were collected in the site. The most represented families are Euphorbiaceae (12 spp.), Rubiaceae (10 spp.), Annonaceae (7 spp.), Fabaceae, Moraceae, Malvaceae (6 spp. each) while the most represented genera are Diospyros L. (4 spp.), Cola Schott & Endl. and Vitex L. (3 spp.). Species from the Guineo-Congolese Region (GC) are the most abundant (72%). They are followed by West African endemic species (GCW, 19%). Microphanerophytes (mp) are the most abundant and represent more than 40% of the species. Three vulnerable species were found in this plot: Campylospermum amplectens, Placodiscus boya and Trichoscypha cavalliensis. Thus, the preservation of this forest is more than necessary. 展开更多
关键词 Co-Occurring Species Aubregrinia taïensis Forest Threatened Species Côte d’Ivoire
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Identification of the Major Allergen in Greasy-Back Shrimp (Metapenaeus ensis) by MALDI-TOF-MS 被引量:1
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作者 Samee Haider 《Journal of Ocean University of China》 SCIE CAS 2010年第2期178-184,共7页
In order to better understand shrimp allergen,some basic characters of the major allergen of greasy-back shrimp(Metapenaeus ensis)were investigated.The major allergen was extracted and separated,and its peptide mass f... In order to better understand shrimp allergen,some basic characters of the major allergen of greasy-back shrimp(Metapenaeus ensis)were investigated.The major allergen was extracted and separated,and its peptide mass fingerprint(PMF)wasanalyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF-MS).After screening inthe NCBI database with Mascot searching engine,the results indicated that the major allergen of greasy-back shirmp was muscletropomyosin.Database matching search showed that the top protein matched,i.e.the tropomyosin from giant tiger prawn(Penaeusmonodon),had a Mowse value of 268.In addition,there were 27 queries matched with the allergen in greasy-back shirmp with anamino acid sequence coverage value of 65%.The matching scores and the sequence coverage values were also high with tropomy-osins of other invertebrates,including Tyrophagus putrescentiae and Lepisma saccharina.These results indicated that the allergen ofMetapenaeus ensis had high homology with other crustacean allergens,and provided molecular explanations for the highcross-reactivity of the major allergens between crustaceans and some other invertebrates. 展开更多
关键词 Metapenaeus ensis ALLERGEN MALDI-TOF-MS IDENTIFICATION
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1—NITROAKNADININE,A NOVEL NITRO—HASUBANAN ALKALOID FROM STEPHANIA SUTCHUEN ENSIS 被引量:2
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作者 Yu Rui ZHAO Tong Fang ZHAO +1 位作者 Sheng LAI Xian Kai WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第2期145-148,共4页
A novel hasubanan alkaloid has been isolated along with the known aknadinine from the fresh roots of Stephania sutchenensis.Its structure has been established as 1—nitroaknadinine from detailed spectral studies and c... A novel hasubanan alkaloid has been isolated along with the known aknadinine from the fresh roots of Stephania sutchenensis.Its structure has been established as 1—nitroaknadinine from detailed spectral studies and confirmed by chemical correlation with aknadinine.The novel alkaloid is the first nitro-hasubanan and also the first example of naturally occurring nitro—alkaloids. 展开更多
关键词 NITROAKNADININE A NOVEL NITRO HASUBANAN ALKALOID FROM STEPHANIA SUTCHUEN ensis
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Immunocytochemical localization of neuropeptide Y,serotonin,substance P and β-endorphin in optic ganglia and brain of Metapenaeus ensis
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作者 叶海辉 王桂忠 +2 位作者 金朱兴 黄辉洋 李少菁 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2006年第4期384-389,共6页
By using immunocytochemistry method of Strept Avidin-Biotin-Complex, four kinds of antisera raised against rabbits were applied to observe the immunoreactive neurons and neuropils of sero-tonin (5-HT), neuropeptide Y ... By using immunocytochemistry method of Strept Avidin-Biotin-Complex, four kinds of antisera raised against rabbits were applied to observe the immunoreactive neurons and neuropils of sero-tonin (5-HT), neuropeptide Y (NPY), substance P (SP) and β-Endorphin (β-Ep) in optic ganglia and brain of Metapenaeus ensis. The results showed that, the 5-HT-immunoreactive cells were located in all the four neuropils of optic ganglia. Immunoreactivity of 5-HT was detected in anterior medial protocerebrum neuropils (AMPN), and the inner and outer lateral beside olfactory lobe (OL) of deutocerebrum. The presence of NPY-immunoreactive cells was found in all the four neuropils of the optic ganglia. NPY-immunoreactivity occurred in the anterior median cell cluster, lateral cell cluster of protocerebrum, and cell cluster beside OL and AMPN. SP-immunoreactivity was found in medulla terminalis (MT) of optic ganglia, and lateral cell cluster of protocerebrum and posterior lateral cell cluster of tritocerebrum. β-Ep-immunoreactive cells were in MT only. In conclusion, these specific distribution patterns of the four immunoreactive substances can be used as morphological clues for understanding their different neuro-physiological functions. 展开更多
关键词 Metapenaeus ensis optic ganglia BRAIN IMMUNOCYTOCHEMISTRY
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The Characterisation of Residual Strain in Ensis siliqua Shells
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作者 D. J. Scurr R. J. Cernik +2 位作者 S. P. Thompson P. M. Mummery S. J. Eichhorn 《Journal of Bionic Engineering》 SCIE EI CSCD 2006年第1期33-38,共6页
This study reports the variation of residual strains within the posterior ventral area of the Ensis siliqua mollusc shell, as determined using glancing incidence synchrotron X-ray diffraction. The outer layer of this ... This study reports the variation of residual strains within the posterior ventral area of the Ensis siliqua mollusc shell, as determined using glancing incidence synchrotron X-ray diffraction. The outer layer of this structure exhibits a tensile strain, in contrast to a compressive strain observed within the inner layer. Fluctuations in unit cell parameters for the inner layer have been determined, showing that the microscopic prismatic layer of the structure exhibits a compressive strain orientated parallel to the surface of the shell. This is thought to enhance the crack deflection properties of this layer, and aid in resisting catastrophic failure. Further analysis of residual strains has been performed using the same method, throughout several stages of compressive testing of the anterior dorsal region of the shell. This identified no variation in residual strains at various levels of loading, and it is therefore proposed that load may be transferred via the organic matrix of mollusc shell structures. A Raman spectroscopic investigation, comparing whole and powdered shell with non-biogenic aragonite, has shown that residual strains are also present in this analagous material which is devoid of organic content. This indicates that the observed strain is not entirely due to the organic matrix. 展开更多
关键词 ensis siliqua shell residual strain synchrostron X-ray diffraction
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Study on genetic diversity of cultivated populations in 4 species of shrimps 被引量:3
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作者 LiZhongbao WuZhongqing 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2003年第1期97-102,共6页
Genetic diversity of cultivated populations was investigated using assay of vertical slabpolyacrylamide gel electrophoresis in 4 species of shrimps, which were Penaeus japonicus, Penaeus monodon , Penaeus vannamei and... Genetic diversity of cultivated populations was investigated using assay of vertical slabpolyacrylamide gel electrophoresis in 4 species of shrimps, which were Penaeus japonicus, Penaeus monodon , Penaeus vannamei and Metapenaeus ensis, The results showed that the mean number of alle-les per locus (A) is 1.3±0.2, 1.3±0.1, 1.3±0.1 and 1.3 ±0.1 respectively; the percentage of polymorphic loci (P0.95) is 12.5, 6.7, 20 and 23.5 respectively; the expected heterozygosity (He) is 0.042±0.034,0.042±0.031, 0.094±0.042 and 0.097±0.047 respectively; and the observed heterozygosity (H0)is 0.029±0.024, 0.028±0.023,0.154±0.082 and 0.150±0.084 respectively. The difference of genetic diversity is obvious in 4 species of shrimps. The degree of genetic diversity is M. ensis > P. vannamei > P. japonicus > P. monodon. In short, the lower level of genetic diversity is estimated in 4 species of shrimps. 展开更多
关键词 Penaeus vannamei Penaeus japonicus Penaeus monodon Metapenaeus ensis ALLOZYME genetic diversity
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Patterns of forest composition and their long term environmental drivers in the tropical dry forest transition zone of southern Africa 被引量:1
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作者 Vera De Cauwer Coert J.Geldenhuys +2 位作者 Raf Aerts Miya Kabajani Bart Muys 《Forest Ecosystems》 SCIE CSCD 2017年第1期33-44,共12页
Background: Tropical dry forests cover less than 13 % of the world's tropical forests and their area and biodiversity are declining. In southern Africa, the major threat is increasing population pressure, while drou... Background: Tropical dry forests cover less than 13 % of the world's tropical forests and their area and biodiversity are declining. In southern Africa, the major threat is increasing population pressure, while drought caused by climate change is a potential threat in the drier transition zones to shrub land. Monitoring climate change impacts in these transition zones is difficult as there is inadequate information on forest composition to allow disentanglement from other environmental drivers. Methods: This study combined historical and modern forest inventories covering an area of 21,000 km2 in a transition zone in Namibia and Angola to distinguish late succession tree communities, to understand their dependence on site factors, and to detect trends in the forest composition over the last 40 years. Results: The woodlands were dominated by six tree species that represented 84 % of the total basal area and can be referred to as Bdikioea - Pterocarpus woodlands. A boosted regression tree analysis revealed that late succession tree communities are primarily determined by climate and topography. The Schinziophyton rautanenfi and Baikiaea plurijuga communities are common on slightly inclined dune or valley slopes and had the highest basal area (5.5 - 6.2 m^2 ha&-1). The Burkea africana - Guibourtia coleosperma and Pterocarpus angolensis - Diafium englerianum communities are typical for the sandy plateaux and have a higher proportion of smaller stems caused by a higher fire frequency. A decrease in overall basal area or a trend of increasing domination by the more drought and cold resilient B. africana community was not confirmed by the historical data, but there were significant decreases in basal area for Ochna pulchra and the valuable fruit tree D. englerianum. Conclusions: The slope communities are more sheltered from fire, frost and drought but are more susceptible to human expansion. The community with the important timber tree P. angolensis can best withstand high fire frequency but shows signs of a higher vulnerability to climate change. Conservation and climate adaptation strategies should include protection of the slope communities through refuges. Follow-up studies are needed on short term dynamics, especially near the edges of the transition zone towards shrub land. 展开更多
关键词 Baikiaea woodland Tree community Namibia boosted regression trees Pterocarpus ango/ensis Disturbance Miombo Ecoregion Climate change
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变电站站间联络率研究 被引量:2
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作者 刘思源 林凌雪 肖鸣晖 《吉林电力》 2016年第5期20-23,共4页
目前,国内外关于优化变电站站间联络率从而提高供电可靠性的研究十分有限,针对这一现状,计及110kV变电站电气主接线和设备运行状态,从可靠性的角度出发,在主变压器满足N-1原则的基础上,以系统电量不足指标(ENSI)最小为优化目标,研究变... 目前,国内外关于优化变电站站间联络率从而提高供电可靠性的研究十分有限,针对这一现状,计及110kV变电站电气主接线和设备运行状态,从可靠性的角度出发,在主变压器满足N-1原则的基础上,以系统电量不足指标(ENSI)最小为优化目标,研究变电站出线的最优站间联络比率。应用基于MATLAB的多元线性回归模型推导联络率与变电站主变压器数量、变电站负载率之间的函数关系,建立模型求解,得到了变电站最佳站间联络率。 展开更多
关键词 变电站 站间联络率 电力系统可靠性 电量不足指标(ENSI) N-1原则 多元线性回归
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