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61.
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The efficient storage and germination of seeds underpin the effective use of plants for livelihoods and sustainable development. A total of 204 wild species useful for local communities of the Tehuacán–Cuicatlán Valley were collected and stored in seed banks in country for long term conservation, and 66 % (i.e., 134) duplicated in the U.K., as an effective means of ex situ conservation. Of the 204 species, 147 (122 of which also duplicated in the U.K.) were previously listed as useful plants in the ethnofloristic inventory of the Valley. Based on literature surveys, we found that one of the major impediments to the use of stored seeds of wild species is the lack of knowledge of how to germinate the seed. In detailed studies, we found that seeds of 18 useful plant species from 10 different families germinated readily and could be propagated. In contrast, four species (Actinocheita filicina, Bursera submoniliformis, Karwinskia mollis and Lippia graveolens) produced dormant seeds and therefore further studies are needed before their use can be maximised in large scale propagation programmes in support of conservation and livelihoods. Overall, this large-scale study on useful wild plant species in Mexico confirms that conventional seed banking can effectively support sustainable development and livelihood programmes.  相似文献   
63.
An unusually high incidence of infectious keratoconjunctivitis followed by pneumonia and arthritis was observed in beef calves of a managed herd. No Moraxella spp. or bacteria other than Mycoplasma spp. were obtained from conjunctival and nasal swabs. A strategy was designed for characterization of bovine mycoplasmas at species and strain level on the basis of a combination of molecular tools and the immunoblotting method. The strategy made it possible to rapidly assign the bacterium responsible for this outbreak to one of the phylogenetic clusters of bovine mycoplasmas delineated in this study and then to identify it as Mycoplasma bovis. The strain, designated Sar 1, showed a 100% 16S rDNA sequence identity with two European strains (120/81 and MC3386) isolated in Germany and Ireland, respectively, and hosts a vsp gene analog to the vspA, vsp422-4, and vsp422-8 genes of the M. bovis reference strain PG45T and of the field strain 422. The use of a cross-reactive rabbit serum developed against the Mycoplasma agalactiae immunodominant antigen P48 confirmed the molecular findings. The immunological response of calves against M. bovis was also investigated. This is the first report on the occurrence of M. bovis on the Island of Sardinia (Italy).  相似文献   
64.
  1. Species of conservation concern are usually considered important elements in site prioritization for biodiversity conservation. To overcome the lack of information on species conservation status, multidimensional measures of species rarity can be used as proxies of species vulnerability.
  2. Under this assumption, a two‐step protocol for site prioritization of aquatic groundwater‐dependent ecosystems is proposed using invertebrate vulnerability estimated from species' traits. In the first step, each species occurring in the sites of interest are scored according to their vulnerability. In the second step, sites are prioritized using species' scores.
  3. Species vulnerability scores are based on five dimensions, for which various traits are scored: (i) geography, (ii) ecology, (iii) biology, (iv) population, and (v) evolutionary history. For each species, the scores of the various traits belonging to the same dimension are multiplied to obtain a synthetic score. These scores are then ranked into four classes and, for each dimension, each species receives a new score that reflects its rank. The sum of these scores represents the species' overall score.
  4. Site conservation priorities are assessed by combining species scores into three indices: Sum of Species Scores, Biodiversity Conservation Concern (which relates the sum of species scores with the local species richness) and Groundwater Biodiversity Concern (which is the average of the former two). The protocol is illustrated using case studies in Italy and it is fully implemented in the software AQUALIFE which is freely available at: http://app.aqualifeproject.eu by registered users.
  5. Sensitivity analyses showed that the protocol is robust against the lack of information on species biology or sampling limitations. However, trait scoring rests with the user, who must be familiar with the study group.
  6. This approach can be applied at any spatial scale and to different types of aquatic groundwater‐dependent ecosystems.
  相似文献   
65.
66.
Locomotor primitives in newborn babies and their development   总被引:1,自引:0,他引:1  
How rudimentary movements evolve into sophisticated ones during development remains unclear. It is often assumed that the primitive patterns of neural control are suppressed during development, replaced by entirely new patterns. Here we identified the basic patterns of lumbosacral motoneuron activity from multimuscle recordings in stepping neonates, toddlers, preschoolers, and adults. Surprisingly, we found that the two basic patterns of stepping neonates are retained through development, augmented by two new patterns first revealed in toddlers. Markedly similar patterns were observed also in the rat, cat, macaque, and guineafowl, consistent with the hypothesis that, despite substantial phylogenetic distances and morphological differences, locomotion in several animal species is built starting from common primitives, perhaps related to a common ancestral neural network.  相似文献   
67.
The causative agents of avian mycobacteriosis in pet birds are rarely identified. The aim of this study is to add information about the etiology of avian mycobacteriosis. The identification of mycobacterium species in 27 cases of avian mycobacteriosis in pet birds was investigated by polymerase chain reaction (PCR) and sequencing of a rRNA hypervariable region. Avian mycobacteriosis appeared to be an infrequent diagnosis. Interestingly, a few cases of avian mycobacteriosis were recorded in very young birds. The most commonly affected species were the canary (Serinus canarius), the Eurasian goldfinch (Carduelis carduelis) and the red siskin (Spinus cucullatus). All but one bird were infected with Mycobacterium genavense. Mycobacterium avium was identified only in one case.  相似文献   
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