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101.
G. Droin 《International Journal of Anthropology》2005,20(3-4):307-324
Why speak still today about endemic goiter and cretinism in the Alps? because thyroid pathology represents the discovery paradigm of endocrinology, the first explanatory and curative anatomo-clinic schema of endocrinology. Great figures, naturalists, physicians, biologists, surgeons, many of which issued from the French (Fodéré, 1792), Swiss (Kocher, Nobel prize in 1910), Austrian (Wagner-Jauregg, Nobel prize in 1927) and Italian Alps (Malacarne, 1780) contributed to these discoveries though the centuries and deserve for this reason to be honored. The present work is a historical and iconographic review, which relates the evolution of this pathology and it's representations, from Antoquity to the present days. These representations have beeon described in several monographs, among which Merke's (1984) extraordinary “History and Iconography of Endemic Goiter and Cretinism”, but also in literary works with Balzac's “Le médecin de campagne”. It's only in the beginning of the XX century that the inclusion of iodized salt in the diet has radically transformed the disease and its consequences. But this pathology has left painful traces in the collective imagination of Alpine people. Finally the anxiety provoked by the crossing of Tchernobyl “radioactive cloud” over France's South-Est, in 1986, expresses today's concerns about thyroid problems, which are represented by the augmentation, real or imaginary, of the number of cases of thyroid cancer. 相似文献
102.
Jelena Blaženčić Branka Stevanović Živojin Blaženčić Vladimir Stevanović 《Biodiversity and Conservation》2006,15(11):3445-3457
The occurrence of 47 species of all the six recent genera of charophytes recorded in the Balkans is demonstrated. Our aim
was to assess their status of threat according to the 2001 IUCN threat categories and criteria, in order to establish the
Red List of Charophytes distributed in the Balkan Peninsula. The List underlines the diversity of charophytes in this part
of the world and provides guidelines for its conservation. Analysis of the charophytes in each category of threat has provided
a general overview of their distribution, species richness, population features and possibility of survival throughout the
various regions of the Balkan Peninsula. 相似文献
103.
亚洲中部荒漠区的植物特有属 总被引:22,自引:0,他引:22
系统地列出了亚洲中部荒漠区的13个植物特有属或近特有属——绵刺属、沙冬青属、四合木属、百花篙属、革苞菊属、河西菊属、喀什菊属、紊篙属、连蕊芥属、钝基草属、合头黎属、戈壁黎属、霸王属。这些属都是单种属或双种属,分类上属于孤立的类群;演化系统上是既起源古老而又进化的类群;生态上都是早生植物,绝大多数是荒漠种,其生活型灌木和半灌木占优势;地理分布上阿拉善荒漠区是其特有属的分布中心;起源上是多元的。 相似文献
104.
Vegetation mapping and nature conservation: a case study in Terceira Island (Azores) 总被引:1,自引:0,他引:1
In order to emphasize the importance of vegetation mapping for nature conservation purposes a case study in Terceira island (Azores) is presented, in which the importance of the natural vegetation of the eastern slope of Santa Bárbara volcano (which is part of the Site of Community Importance of Santa Bárbara–Pico Alto) is evaluated through the elaboration of its vegetation map. Fourteen (14) different natural vegetation types were identified: grasslands (1 type), peat bogs (2 types), scrubs (2), forests (5), successional vegetation (3) and vegetation of rocky slopes (1). All communities are protected under the Habitat and Species Directive (EC/92/43) and most of them are endemic to the Azores Islands. This fact, together with the significant number of Azorean endemic taxa (18), Macaronesian endemic taxa (5) and species protected under the Habitat and Species Directive (7), gives this area an important conservation value that justifies future protection actions. Vegetation mapping is an important tool for the characterization, evaluation and implementation of managing plans of natural areas of the Azores islands. The use of a floristic-based classification, supported by multivariate analysis and structural data, is an efficient methodology for the construction of these maps. The data collected comprise an important set of information about the distribution and abundance of natural vegetation types and endemic and rare species. This information was not available until now and is indispensable for the elaboration of management plans of Special Zones for Conservation that will be part of the NATURA 2000 network. 相似文献
105.
一类具有常数迁入且总入口在变化的SIRI传染病模型的稳定性 总被引:3,自引:0,他引:3
讨论一类具有常数迁入率,染病类有病死且有效接触率依赖于总人数的SIRI传染病模型.给出了基本再生数σ的表达式.如果σ≤1,则疾病消除平衡点是全局稳定的;如果σ>1,则存在唯一的传染病平衡点且是局部渐近稳定的.对具有双线性传染率和标准传染率的相应模型,进一步证明了当σ>1时传染病平衡点的全局稳定性. 相似文献
106.
We evaluated the phylogenetic relationships of the Taiwan Firecrest or Flamecrest, Regulus goodfellowi, on the basis of two mitochondrial markers (cytochrome b, 16S rRNA) and territorial song. Genetic samples from eighteen subspecies of all currently accepted crest and kinglet species
were available for comparison. In all molecular tree reconstructions it was clearly apparent the Taiwan endemic species was
the sister species of all the palearctic Goldcrests (Regulus regulus) from Bayesian inference of phylogeny, although with weak bootstrap support and conflicting position in the ML and NJ trees.
Genetic distances based on cyt-b sequences between R. goodfellowi and subspecies of R. regulus ranged between 6.1 and 8.2%. Two separate divergence time estimates dated the colonization of Taiwan to the mid to late Pliocene
from 5–2 Mya. The high-pitched territorial songs of R. goodfellowi strongly resemble those of Sino-Himalayan Goldcrests (ssp. himalayensis, sikkimensis, and yunnanensis), but the terminal flourish typical of Goldcrests is invariable and only rarely included in songs of R. goodfellowi. Discriminant analysis of spectral and temporal characteristics separated the songs of the Southeast Asian populations from
those of two other large clusters, the Canarian and Northwest Palearctic. Songs of R. goodfellowi were 100% correctly assigned and well distinguishable from Sino–Himalayan songs. Cluster analysis of Regulus songs strongly corroborated the sister group relationship of R. goodfellowi and R. regulus as reconstructed from concatenated mitochondrial sequence data. All results from molecular and acoustic analysis justify
the species rank of the Taiwan endemic species and suggest that it is only distantly related to the firecrest clade (R. ignicapillus, R. madeirensis). 相似文献
107.
Pasquale Moneglia Aurélien Besnard Jean-Claude Thibault Roger Prodon 《Journal of Ornithology》2009,150(3):577-583
The Corsican Nuthatch Sitta whiteheadi is a bird endemic to Corsica Island and has a very small population. Its habitat, Corsican pine Pinus nigra laricio forest, is currently restricted to less than 16,000 ha and is threatened by forest fires. In this article, we aim (1) to
evaluate the effects of a large wildfire on a Nuthatch population, and (2) to identify the habitat features that influence
the presence/absence of the Nuthatch after fire, so as to promote appropriate forestry practices after fire. The study has
been conducted on a study plot of 300 ha which is part of a larger area severely burnt in August 2003. Habitat characteristics
have been investigated on 39 plots of 1,225 m2 occupied by the bird, and 22 randomly chosen plots without the Nuthatch. We observed a decrease of 37.5% in Nuthatch abundance
the first spring after the fire, but the impact showed great local variation as a function of fire severity. Logistic modelling
showed that the presence of Nuthatch mainly depended on the degree of crown alteration: the Nuthatch tended to be present
when at least one pine had less than 2.5 m of crown burned. We have no evidence of any direct fire-induced mortality, but
several effects of fire can explain this population decrease, namely, the reduction of canopy volume, the decrease of the
amount of pine seeds, and the reduction of nest-site availability. These results permit us to propose a simple criterion that
can help in choosing the plots to be cut where salvage logging is necessary. 相似文献
108.
Elevational patterns of species richness and endemism for some important taxa in the Hengduan Mountains, southwestern China 总被引:1,自引:0,他引:1
Da-Cai Zhang Yong-Hong Zhang David E. Boufford Hang Sun 《Biodiversity and Conservation》2009,18(3):699-716
We describe the elevational patterns of species richness and endemism of some important taxa in the Hengduan Mountains, southwest
China. Species richness data came from publications, an online database, herbaria and field work. Species richness was estimated
by rarefaction and interpolation. The Hengduan Mountains region was divided into a southern and northern subregion, and all
species were assigned to four groups based on their distributional range within this region. The conditional autoregressive
model (CAR) was used to relate species richness and explanatory variables. The elevational patterns of total, endemic and
non-endemic species richness, at subregion and entire region scales, presented to be unimodal and peaked at similar elevations.
Area size was strongly related with species richness, and was more powerful in explaining variation in species richness in
the northern subregion than in the southern subregion. A single climatic variable (mean annual rainfall, potential evapotranspiration
or moisture index) showed a weak relationship with the elevational pattern of species richness. Area and climatic variables
together explained more than 67% of the variation in non-endemic richness, 53% in total richness, and 50% in endemic richness.
There were three patterns of endemism at the generic level with increasing elevation: namely endemism increased, decreased,
or peaked at middle elevations. All selected taxa have experienced rapid speciation and evolution within this region, which
plays an important role in the uniform elevational patterns of total, endemic and non-endemic richness, and in the multiform
elevational patterns of endemism.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
109.
Zuhao Huang Naifa Liu Yian Xiao Yalin Cheng Wenfeng Mei Longying Wen Lixun Zhang Xiaoping Yu 《Molecular phylogenetics and evolution》2009,53(2):378-383
The taxonomic status of some genera within the Phasianidae remains controversial. To demonstrate the phylogenetic relationships of four endemic genera (Tetraophasis, Ithaginis, Crossoptilon and Chrysolophus) and other 11 genera of Phasianidae in China, a total of 1070 nucleotides of mitochondrial DNA (mtDNA) control-region genes were sequenced. There are 376 variable sites including 345 parsimony sites. The genetic distance ranged from 0.067 (Chrysolophus and Phasianus) to 0.181 (Perdix and Bambusicola) among the 15 genera. Maximum likelihood method was used to construct a phylogenetic tree, which grouped all the genera into two deeply divergent clades. Perdix was shown to be a non-partridge genus. Alternatively, it appears ancestral to either partridges or pheasants. The sibling taxa of the four endemic genera were Lophophorus, Tragopan, Lophura and Phasianus, respectively. Calibrated rates of molecular evolution suggested that the divergence time between the four genera and related taxa was 4.00–5.00 million years ago, corresponding to the Pliocene. Considering their molecular phylogenetics, fossil and geographical distribution patterns, the four endemic genera might have originated in the southwestern mountains in China. 相似文献
110.
Short-term signals of climate change along an altitudinal gradient in the South Alps 总被引:2,自引:0,他引:2
Brigitta Erschbamer Thomas Kiebacher Martin Mallaun Peter Unterluggauer 《Plant Ecology》2009,202(1):79-89
Short-term changes in plant species number, frequency and composition were studied along an altitudinal gradient crossing
four summits from the treeline ecotone to the subnival zone in the South Alps (Dolomites, Italy). Large-scale (summit areas)
and small-scale patterns (16 plots of 1 m2/summit) were monitored. After 5 years, a re-visitation of the summit areas revealed
a considerable increase of species richness at the upper alpine and subnival zone (10% and 9%, respectively) and relatively
modest increases at the lower alpine zone and the treeline ecotone (3% and 1%, respectively). At the small scale, the results
were partly different, with species richness decreasing at the lower summits and increasing at the higher summits. The changes
can most likely be attributed to climate warming effects and to competitive interactions. The main newcomers at the lower
three summits were species from the treeline and the lower altitudinal zones. Only at the highest summit, the newcomers came
from the alpine species pool. At the treeline ecotone, the abundance of Pinus cembra, of dwarf shrubs and clonal graminoid species increased. Here, displacements of alpine species may be predicted for the near
future. At the higher summits, expansions of the established alpine species and further invasions of species from lower altitudes
are forecasted. 相似文献