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151.
152.
Estimating the Local Value of Non-Timber Forest Products to Pendjari Biosphere Reserve Dwellers in Benin 总被引:1,自引:0,他引:1
Fifanou G. Vodouhê Ousmane Coulibaly Charlotte Greene Brice Sinsin 《Economic botany》2009,63(4):397-412
Estimating the Local Value of Non-Timber Forest Products to Pendjari Biosphere Reserve Dwellers in Benin. This paper uses an indices method based on participant ranking of species to quantify use–values of Non-Timber Forest Products
(NTFPs) and the socio-economic factors that influence these values for people living around the Pendjari Biosphere Reserve
in Benin. There were 76 species identified that had a high index value to people. The 10 most valued species were Parkia biglobosa, Adansonia digitata, Vitellaria paradoxa, Tamarindus indica, Lannea microcarpa, Vitex doniana, Hibiscus asper, Melochia corchorifolia, Khaya senegalensis, and Diospyros mespiliformis. Species values were influenced by the vegetative form of the species as well as by the gender of a participant and his/her
affiliation to the ethnic group. The study also illustrates that women had a preference for NTFP species with high commercial
and nutritional values, while men preferred plants that provide construction material and medicine. Moreover, the ethnic group
that historically had more contact and interaction with the vegetation valued NTFPs more than any other group. The difference
in value attributed to species by people was also driven by the vertical transmission of ethnobotanical knowledge in the study
area. For long-term biodiversity conservation, it will be useful to involve the needs of all of the local communities in the
design of a management plan and focus attention on the most important species. 相似文献
153.
We report the development of 18, single-copy, anonymous nuclear loci from the Malagasy plated lizard Zonosaurus madagascariensis. More than 140 clones from a genomic library were examined and 38 potential loci tested across both closely and distantly related lizards. Of the 18 loci reported here, more than half (10) work in closely related zonosaurines although only one successfully amplified a homologous fragment in the distantly related iguanid (Oplurus). Sequences of these loci revealed a high frequency of single nucleotide polymorphisms, supporting previous reports of high levels of intraspecific variation in lizards. 相似文献
154.
Carlos Eduardo Almeida Paula L. Marcet Marcia Gumiel Daniela Maeda Takiya Margareth Cardozo‐de‐Almeida Raquel S Pacheco Catarina Macedo Lopes Ellen M. Dotson Jane Costa 《Journal of vector ecology》2009,34(2):164-173
Triatoma carcavalloi is considered a rare Chagas disease vector often collected inside domiciles in Rio Grande do Sul State. In this Brazilian state, T. carcavalloi has been collected in the same ecotope (rock piles) with two other species (T. rubrovaria and T. circummaculata), with which it also shares morphological characteristics. Previous morphological studies placed T. carcavalloi in the same species complex (“infestans complex”) and subcomplex (“rubrovaria subcomplex”) as T. rubrovaria, whereas T. circummaculata was placed in the “circummaculata complex.” The phylogeny of a group composed of 16 species of triatomines was revaluated with the inclusion of T. carcavalloi by Bayesian analysis using mtDNA sequences of subunits 12S and 16S of the ribosomal RNA, and the cytochrome oxidase I (COI) genes. The phenotypic relationship among T. carcavalloi and related triatomines was also inferred from morphometrics. Phylogenetic results indicate that T. carcavalloi is a sister species of T. rubrovaria, and both were recovered as closely related to T. circummaculata. Morphometric studies confirmed the closeness among T. carcavalloi, T. rubrovaria, and T. circummaculata, prompting the placement of the latter species in the “infestans complex” and “rubrovaria subcomplex.” 相似文献
155.
Raselimanana AP Noonan B Karanth KP Gauthier J Yoder AD 《Molecular phylogenetics and evolution》2009,50(2):336-344
The endemic plated lizards (Gerrhosauridae) of Madagascar are one of the most diverse groups of lizards on the island (19 species) and are found in all ecoregions. On an island that presents so many interesting biological questions, plated lizards are an ideal group for examining patterns of diversification due to their high (but tractable) diversity and wide distribution. To resolve the taxonomy and evolutionary relationships of Malagasy plated lizards, and to explore their biogeographic history, we have generated a molecular phylogeny based on >2kb of both mitochondrial (cob, 1142 bp) and nuclear (NT-3, 419 bp; c-mos, 542 bp) DNA sequences. Phylogenetic relationships and divergence-time estimates indicate Zonosaurinae are monophyletic, arising from a single colonization event, likely from Africa to Madagascar in the Paleogene (Paleocene/early Eocene), with subsequent radiation. Furthermore, our results reveal widespread mischaracterization of species delimitation and assignment based on phenotypic characteristics. Paraphyly of a number of zonosaurine species was strongly supported by our dataset, revealing not only instances of likely cryptic species (phenotypic conservatism) but also phenotypic/genotypic discordance in the delimitation of species (phenotypic variability). These results clearly demonstrate the complex history of biotic diversification on Madagascar and provide novel insight into biogeographic patterns on the island. 相似文献
156.
Brice Rotureau Miguel A. Morales Philippe Bastin Gerald F. Späth 《Cellular microbiology》2009,11(5):710-718
Trypanosomatid parasites are the causative agents of severe human diseases such as sleeping sickness, Chagas disease and leishmaniases. These microorganisms are transmitted via different insect vectors and hence are confronted to changing environments during their infectious cycle in which they activate specific and complex patterns of differentiation. Several studies in Trypanosoma brucei and in different subspecies of Leishmania have shed light on the role of mitogen-activated protein (MAP) kinases in these processes. Surprisingly, several MAP kinases turned out to be involved in the control of flagellum length in the promastigote stage of Leishmania . Recently, a sensory function has been recognized for cilia and flagella in unicellular and multicellular eukaryotes. This review aims to stimulate discussions on the possibility that the Trypanosomatid flagellum could act as a sensory organ through the MAP kinase pathway, with the objective to encourage investigation of this new hypothesis through a series of proposed experimental approaches. 相似文献
157.
Repellent activity of plant essential oils against bites of Lutzomyia migonei (Diptera: Psychodidae)
Nieves E Fernández Méndez J Lias J Rondón M Briceño B 《Revista de biología tropical》2010,58(4):1549-1560
Natural repellents from plant extracts have demonstrated good efficacy against bites of some insect species. The present study evaluated the repellent effect of essential oils extracted from 8 plants species against bites of Lutzomyia migonei, the Leishmania vector. The essential oils were extracted by steam destillation in Clevenger chamber, from the following plants: Hyptis suaveolens, Pimenta racemosa, Piper marginatum, Monticalia imbricatifolia, Pseudognaphalium caeruleocanum, Espeletia shultzii, Plecthranthus amboinicus and Cinnamomun zeylanicum. Repellency tests were performed under laboratory conditions by the human hand method in cage assays, using female colonies of L. migonei. The more effective oils were tested at variable concentrations on different volunteers. The protection percentage and time were calculated. The results showed what oils of P. caeruleocanum and C. zeylanicum were the most effective. Although P. amboinicus oil also had repellent effect showed an irritant effect. The oils P. marginatum, H. suaveolens and P. racemosa showed no repellent effect, while the rest of oil extracts showed significant repellency in variable degrees. P. caeruleocanum and C. zeylanicum oils provided the 95% protection against bites of L. migonei for 3 h. The P. caeruleocanum oil showed the greatest protection time, with a mean over 4h and 3h at concentrations of 50% and 10% respectively. The results suggest that the P. caeruleocanum oil could represent a potential natural repellent against Leishmania vectors. 相似文献
158.
Fiona Connell Kamini Kalidas Pia Ostergaard Glen Brice Tessa Homfray Lesley Roberts David J. Bunyan Sally Mitton Sahar Mansour Peter Mortimer Steve Jeffery 《Human genetics》2010,127(2):231-241
Generalised lymphatic dysplasia (GLD) is characterised by extensive peripheral lymphoedema with visceral involvement. In some cases, it presents in utero with hydrops fetalis. Autosomal dominant and recessive inheritance has been reported. A large, non-consanguineous family with three affected siblings with generalised lymphatic dysplasia is presented. One child died aged 5 months, one spontaneously miscarried at 17 weeks gestation, and the third has survived with extensive lymphoedema. All three presented with hydrops fetalis. There are seven other siblings who are clinically unaffected. Linkage analysis produced two loci on chromosome 18, covering 22 Mb and containing 150 genes, one of which is CCBE1. A homozygous cysteine to serine change in CCBE1 has been identified in the proband, in a residue that is conserved across species. High density SNP analysis revealed homozygosity (a region of 900 kb) around the locus for CCBE1 in all three affected cases. This indicates a likely ancestral mutation that is common to both parents; an example of a homozygous mutation representing Identity by Descent (IBD) in this pedigree. Recent studies in zebrafish have shown this gene to be required for lymphangiogenesis and venous sprouting and are therefore supportive of our findings. In view of the conserved nature of the cysteine, the nature of the amino acid change, the occurrence of a homozygous region around the locus, the segregation within the family, and the evidence from zebrafish, we propose that this mutation is causative for the generalised lymphatic dysplasia in this family, and may be of relevance in cases of non-immune hydrops fetalis. 相似文献
159.
Belarmain Fandohan Achille Ephrem Assogbadjo Romain Glèlè Kakaï Tina Kyndt Emmy De Caluwé Jean Thimothée Claude Codjia Brice Sinsin 《Economic botany》2010,64(3):248-259
Women’s Traditional Knowledge, Use Value, and the Contribution of Tamarind (
Tamarindus indica
L.) to Rural Households’ Cash Income in Benin. This study examined differences in knowledge, use values, and contribution of tamarind (Tamarindus indica) to women’s cash income during the dry season, focusing on seven tribal groups in Benin. Data were gathered using semistructured
individual interviews and monitoring, and were analyzed using quantitative ethnobotanical methods. Principal component analysis
was applied to describe the use value and use forms of tamarind according to different tribes. Tamarind was found to play
an important role in local communities’ livelihoods. Overall, 26 different uses were mentioned for tamarind products. Most
commonly, the fruit (pulp) was used to make beverages, as a laxative and purgative, and it seems to be the only plant part
sold commercially. Bark was frequently used as a medicine to treat wounds, and leaves were used to make porridge and as an
antibiotic. Medicinal, cultural, and material use categories were correlated best with the Fulani, whereas commerce was most
correlated with Gourma tribes (PCA analysis). There were significant differences for tamarind utilization among the tribal
groups, with overall ethnobotanical use values (EUVT) ranging from 10 to 14, and contribution to cash income ranging from 8.8% to 56.4%. In view of its domestication potential,
it is crucial that traditional tribal knowledge of tamarind be preserved and integrated into management policies. Further
development and research needs for utilization and conservation are improvement of commercialization, organization of market
channels, and extent of genetic diversity within and among populations. 相似文献
160.
Nadal B Thetiot-Laurent SA Pin S Renault JP Cressier D Rima G Le Roux A Meunier S Wagner A Lion C Le Gall T 《Bioorganic & medicinal chemistry》2010,18(22):7931-7939
The synthesis of three types of pulvinic acid analogues, using a diversity-oriented strategy starting from a single compound, dimethyl l-tartrate, is described. Lacey-Dieckmann condensation, alcohol dehydration and Suzuki-Miyaura cross-couplings were employed in the course of the analogues syntheses. The evaluation of the antioxidant properties of the 28 synthesized analogues was carried out using antioxidant capacity assays (protection of thymidine and β-carotene) and free radical scavenging assays (DPPH radical and ABTS radical cation). This allowed to assess the relative influence of the groups bonded to the tetronic ring and to the exocyclic double bond on the activity, as well as the importance of this exocyclic double bond. It was shown that the presence of an electron-donating group on the 3-position of the tetronic ring had a beneficial effect. It was shown in several assays that the presence of the exocyclic bond was not crucial to the activity. 相似文献