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1.
Pollination services provided by insects play a key role in English crop production and wider ecology. Despite growing evidence of the negative effects of habitat loss on pollinator populations, limited policy support is available to reverse this pressure. One measure that may provide beneficial habitat to pollinators is England’s entry level stewardship agri-environment scheme. This study uses a novel expert survey to develop weights for a range of models which adjust the balance of Entry Level Stewardship options within the current area of spending. The annual costs of establishing and maintaining these option compositions were estimated at £59.3–£12.4 M above current expenditure. Although this produced substantial reduction in private cost:benefit ratios, the benefits of the scheme to pollinator habitat rose by 7–140 %; significantly increasing the public cost:benefit ratio. This study demonstrates that the scheme has significant untapped potential to provide good quality habitat for pollinators across England, even within existing expenditure. The findings should open debate on the costs and benefits of specific entry level stewardship management options and how these can be enhanced to benefit both participants and biodiversity more equitably.  相似文献   

2.
While hybridization is an important part of the evolutionary process, for rare species mating with more common species hybridization can increase the risks of extinction. By mating with heterospecifics rare species waste valuable reproductive resources and as a result population sizes may decline. If introgression occurs, the rare species can become genetically swamped by alleles from the more common species, rendering it effectively extinct. As a consequence of these risks, hybridization with the more common species Hemideina femorata (Canterbury tree weta) may lead to the extinction of the range restricted species H. ricta (Banks Peninsula tree weta) on Banks Peninsula. The current study uses spatial interpolation to model the distribution of each species and the potential sympatric zone to guide sampling efforts. Polymorphic microsatellite markers and mitochondrial sequence data were used to determine the extent of hybridization between H. ricta and H. femorata. The results confirm that hybridization is possible between these species. However, hybrids and introgression appear to be very rare, suggesting that reproductive isolating barriers are present but incomplete. The threat of extinction to H. ricta via hybridization with H. femorata is low but extreme loss of habitat may cause changes to population densities that could increase the risks of hybridization. Therefore, landowners should be encouraged to conserve native bush.  相似文献   

3.
Hine’s emerald dragonfly (Somatochlora hineana) is distributed in discrete fen and wet meadow habitats over its range from Ontario, Canada, to Missouri, USA. Habitat destruction in the vicinity of Chicago, IL, and other areas lead to its designation as an US federal endangered species in 1995. Our main goal was to delineate the population genetic structure of the species within the northern recovery unit centered on the Door Peninsula in Wisconsin and the southern recovery unit in the Des Plaines River Valley near Chicago, IL. Sites on the Door Peninsula, WI, are in a matrix of agricultural development and second-growth forest and were used as a best available approximation of a pristine system for the dragonfly. We nondestructively sampled 557 adults and larvae from 16 sites in Illinois, Michigan, and Wisconsin from 2008 through 2011 and used ten microsatellite markers to estimate levels of genetic variability, and genetic structure. Mean allelic richness across all sites and years was 5.03 (±0.64) and expected heterozygosity was 0.52 (±0.032). Northern and southern recovery units as designated in the original recovery plan were genetically distinct. We delineated two genetic populations in the northern unit and three within the southern including two disjunct sites.  相似文献   

4.
Nest predation has been identified as the main threat behind the negative population dynamics in chelonian species and in particular in the native Iberian population of the Western Hermann’s tortoise Testudo hermanni hermanni. This endangered subspecies is found within the Albera Nature Reserve, where this study was performed. We selected three formerly high-density tortoise areas to carry out different trials whose aims were to: (1) identify nest predator species, (2) test the success of reducing the shrub cover to reduce nest predation in potential new nesting areas, and (3) assess fencing efficiency to exclude predators. For the first objective, camera-trapping was used to identify nest predators, with sardines and artificial tortoise nests as lures. We obtained 825 pictures of possible predators and demonstrated that the beech marten was the most abundant predator in the study areas, followed by the badger and the wild boar. For the second objective, predation of artificial nests was compared between plots managed for shrub reduction (27 plots of 4, 25, and 100?m2) and a natural nesting area (nine control plots of 100?m2). Predation was strong in the managed plots (43.6% after 48?h and 99.6% after 144?h) but highest in the control area (100% after 48?h). Surprisingly, predation occurred at an even faster pace when we repeated the trial with a single artificial nest (in order to reduce odor intensity). Finally, we compared predation rates between eight fenced and eight unfenced plots of 100?m2. Fencing was partially effective to control nest predation because it excluded all the main predator species except the beech marten, which learned to go through it. Since the nest predation threat to this endangered population is critical, new strategies are needed to control nest predation by taking into account the ability of predators to learn nest location.  相似文献   

5.

Background

Thyroid lymphomas are an exceptional finding in patients with thyroid nodules. Burkitt’s lymphoma is one of the rarest and most aggressive forms of thyroid lymphomas, and its prognosis depends on the earliness of medical treatment. Given the rarity of this disease, making a prompt diagnosis can be challenging. For instance, fine-needle aspiration (FNA) cytology, which is the first-line diagnostic test that is performed in patients with thyroid nodules, is often not diagnostic in cases of thyroid lymphomas, with subsequent delay of the start of therapy.

Case presentation

Here we report the case of a 52-year-old woman presenting with a rapidly enlarging thyroid mass. Thyroid ultrasonography demonstrated a solid hypoechoic nodule. FNA cytology was only suggestive of a lymphoproliferative disorder and did not provide a definitive diagnosis. It is core needle biopsy (CNB) that helped us to overcome the limitations of routine FNA cytology, showing the presence of thyroid Burkitt’s lymphoma. Subsequent staging demonstrated bone marrow involvement. The early start of an intensive multi-agent chemotherapy resulted in complete disease remission. At 60 months after the diagnosis, the patient is alive and has not had any recurrence.

Conclusions

Clinicians should be aware that thyroid Burkitt’s lymphoma is an aggressive disease that needs to be treated with multi-agent chemotherapy as soon as possible. To diagnose it promptly, they should consider to order/perform a CNB in any patient with a rapidly enlarging thyroid mass that is suspicious for lymphoma.
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6.

Background

Intravascular papillary endothelial hyperplasia (known also as Masson’s tumor) is a benign vascular lesion that commonly occurs in the skin and is rarely found in solid organs, especially in the kidney. In what follows, we will look into the first case of an unexpectedly diagnosed Masson’s tumor of the kidney presenting as a suspicious renal cyst.

Case presentation

A 61-year-old Arab man presented with a left renal cyst, incidentally revealed by ultrasonography. The laboratory values were unremarkable. Computed tomography and magnetic resonance imaging demonstrated a 38 mm left renal midportion Bosniak IV cyst. Our patient underwent a radical nephrectomy. Histopathology revealed the diagnosis of intravascular papillary endothelial hyperplasia. There was no recurrence detected after 9 years of follow-up.

Conclusions

Renal intravascular papillary endothelial hyperplasia is a rare benign tumor which can mimic a suspicious renal mass on radiological findings. Thus, this entity should be considered more often in the thick of the diagnostic possibilities in order to avoid unnecessary nephrectomies.
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7.
Based on an updated census for the endangered Dupont’s lark (Chersophilus duponti), we conducted a phytosociological survey of 167 sites representative of the distribution area of the species in Europe. Results were used as a starting point for conservation assessment. According to our observations, the bird selects flat deforested areas colonized by small shrubs corresponding to successional, subclimax stages that are either naturally or artificially exploited. Four groups of scrubs were occupied by the bird: (1) supramediterranean dwarf cushion scrubs dominated by Genista pumila ssp. rigidissima or Erinacea anthyllis; (2) gypicolous shrublands and grasslands associated with Lygeum spartum; (3) shrubs dominated by chamaephytes producing allelopathic substances (Thymus, Lavandula, Salvia) and showing different facies according to the level of disturbance; and (4) supramediterranean acidophilous scrubs dominated by Cistus, Erica or Cytisus species. As management measures, we propose reducing tree density in flat areas, promoting the growth of chamaephytes by clearing phanerophytes, and encouraging traditional low-level transhumance grazing. These measures will provide high-quality habitats and help preserve, or even expand, habitable patches to ensure the viability of the European metapopulation of this rare and sensitive songbird.  相似文献   

8.
That holobionts (microbial communities and their animal or plant hosts) are units of selection squares poorly with the observation that microbes are often recruited (horizontally acquired) from the environment, not passed down vertically from parent to offspring, as required for collective reproduction. The taxonomic makeup of a holobiont’s microbial community may vary over its lifetime and differ from that of conspecifics. In contrast, biochemical functions of the microbiota and contributions to host biology are more conserved, with taxonomically variable but functionally similar microbes recurring across generations and hosts. To save what is of interest in holobiont thinking, we propose casting metabolic and developmental interaction patterns, rather than the taxa responsible for them, as units of selection. Such units need not directly reproduce or form parent-offspring lineages: their prior existence has created the conditions under which taxa with the genes necessary to carry out their steps have evolved in large numbers. These taxa or genes will reconstruct the original interaction patterns when favorable conditions occur. Interaction patterns will vary (for instance by the alteration or addition of intermediates) in ways that affect the likelihood of and circumstances under which such reconstruction occurs. Thus, they vary in fitness, and evolution by natural selection will occur at this level. It is on the persistence, reconstruction, and spread of such interaction patterns that students of holobiosis should concentrate, we suggest. This model also addresses other multi-species collectively beneficial interactions, such as biofilms or biogeochemical cycles maintaining all life.  相似文献   

9.
Four non-exclusive hypotheses have been proposed to explain the alternative nest-building behaviour of raptors: (1) nests as an advertising signal in territories, (2) frustration nests, (3) competition avoidance by nest-site and (4) reduction of nest ectoparasites. We report here data collected during an observational study of a population of Bonelli’s Eagle Hieraaetus fasciatus in southeastern Spain. Our data does not support the first two hypotheses based on the closeness of nests within territories, the lack of correlation between the number of nests and the distance to neighbours and the construction of secondary nests at similar frequencies after breeding failures as after successes. In contrast, the construction of alternative nests to avoid competition with other cliff-nesting raptor species breeding nearby was clearly important since 30% of the pairs obtained some direct benefit from the existence of alternative nests within their territories. We also found abundant Coleoptera (Dermestidae) and Diptera (Carnidae, Calliphoridae and Phoridae) as ectoparasites in nests, and the alternative use of nests, synergetically with the presence of greenery as mechanisms for avoiding ectoparasites, was an important factor for the breeding success of the eagle. Our data suggest that competition avoidance and, in particular, the reduction of nest ectoparasite hypotheses are the more plausible explanations for the maintenance of alternative nests in raptors.  相似文献   

10.
Some informal youth associations ceased to exist with the collapse of the USSR, but others continue to operate to this day, although the moral convictions of members have changed and modernized. This article describes the types, features and differences of some modern Russian subcultures as well as subcultures of the Soviet era. The author explores the process of transformation of traditional ideas about the place of a young person in society, as well as gender relations and functions of an individual in the youth environment. Also analyzed is the active development of a new stage of formation and development of criminal subculture in Russia, which belongs within the parameter of a “classical” criminal subculture. Having considered youth subcultures, the author identifies styles that have become constant.  相似文献   

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12.
Capsule: We assess biometric variation in the threatened Dupont’s Lark along a wide fraction of its distribution area analysing the largest data set for this bird species available to date, comprising a 28-year period and including birds captured in Spain, Morocco and Tunisia.

Aims: To analyse Dupont’s Lark morphology evaluating five potential sources of divergence: (I) sexual dimorphism, (II) macro-regional differences, (III) climate, (IV) isolation and (V) intraspecific competition.

Methods: Multivariate analysis was used to summarize biometric data. Sexual dimorphism and macro-regional divergence were assessed by generalized linear mixed models. Climate, isolation and intraspecific competition effects on phenotype were explored by means of model averaging.

Results: Sexes differed in wing shape suggesting a sexual selection pressure on males for aerial displays. Males showed longer bills after controlling for body size. We found an increasing Spain?Conclusion: We found convincing results for wing morphology variation in relation to intrasexual competition, as males seem to be subjected to a sexual selection pressure for aerial display and this adaptation strengthens when intraspecific competition increases. We also found solid support for Allen’s rule, with results suggesting that bill size plays an important role in the bird’s thermoregulation, which does not occur in the case of tarsus. Although Bergmann’s rule is not supported in relation to minimum annual temperature, we found a relationship with thermal conditions in the breeding season, as well as water availability.  相似文献   

13.
 Extending Bernstein’s spatial conception of the degrees-of-freedom problem in the human motor system, we introduce a method developed from the theory of non-linear dynamics that allows one to quantify the spatio-temporal, i.e. dynamic, complexity of visuo-motor coordination. The correlation dimension D is used to measure the effective number of dynamic degrees of freedom in the coordination that a subject uses when performing a visuo-motor tracking task. The validity of the estimator employed is demonstrated. Visuo-motor coordination had a low-dimensional (mean D±SD=6.07 ±0.82) dynamic structure, which was consistent with deterministic chaos rather than with pure stochastic noise. D correlated with tracking performance, P. Both D and P were closely related to the degree of visuo-motor compatibility that the task presented to the subject. However, for short periods of training P increased, but D did not. As these seemingly contradictory results suggest, our dynamic conception of the degrees-of-freedom problem may reveal far more intricate visuo-motor interactions than Bernstein could identify on the basis of his spatial analyses of bodily movement patterns and by the methods of evaluation that were available to him at the time. Received: 19 April 1995/Accepted in revised form: 17 June 1996  相似文献   

14.
This study describes diversity patterns in the flora of the Campo-Ma’an rain forest, in south Cameroon. In this area, the structure and composition of the forests change progressively from the coastal forest on sandy shorelines through the lowland evergreen forest rich in Caesalpinioideae with Calpocalyx heitzii and Sacoglottis gabonensis, to the submontane forest at higher elevations and the mixed evergreen and semi-deciduous forest in the drier Ma’an area. We tested whether there is a correlation between tree species diversity and diversity of other growth forms such as shrubs, herbs, and lianas in order to understand if, in the context of African tropical rain forest, tree species diversity mirrors the diversity of other life forms or strata. Are forests that are rich in tree species also rich in other life forms? To answer this question, we analysed the family and species level floristic richness and diversity of the various growth forms and forest strata within 145 plots recorded in 6 main vegetation types. A comparison of the diversity within forest layers and within growth forms was done using General Linear Models. The results showed that tree species accounted for 46% of the total number of vascular plant species with DBH ≥1 cm, shrubs/small trees 39%, climbers 14% and herbs less than 1%. Only 22% of the diversity of shrubs and lianas could be explained by the diversity of large and medium sized trees, and less than 1% of herb diversity was explained by tree diversity. The shrub layer was by far the most species rich, with both a higher number of species per plot, and a higher Shannon diversity index, than the tree and the herb layer. More than 82% of tree species, 90% of shrubs, 78% of lianas and 70% of herbaceous species were recorded in the shrub layer. Moreover, shrubs contributed for 38% of the 114 strict and narrow endemic plant species recorded in the area, herbs 29%, trees only 20% and climbers 11%. These results indicate that the diversity of trees might not always reflect the overall diversity of the forest in the Campo-Ma’an area, and therefore it may not be a good indicator for the diversity of shrubs and herbaceous species. Furthermore, this suggests that biodiversity surveys based solely on large and medium sized tree species (DBH ≥0cm) are not an adequate method for the assessment of plant diversity because other growth form such as shrubs, climbers and herbs are under-represented. Therefore, inventory design based on small plots of 0.1 ha, in which all vascular plants with DBH ≥1 cm are recorded, is a more appropriate sampling method for biodiversity assessments than surveys based solely on large and medium sized tree species.  相似文献   

15.
Dear Editor, We report a case of HBV reactivation in an anti-HBs positive,anti-HBc positive non-Hodgkin's lymphoma patient.Hepatitis B virus (HBV) reactivation is a well-recognized complication of patients undergoing chemotherapy or immunosuppressive therapy for lymphomas.The presence of antibodies to the hepatitis B surface antigen (anti-HBs) has been identified to be a factor preventing HBV reactivation in patients with occult HBV infection receiving chemotherapy.In this paper,we present a non-Hodgkin Lymphoma patient who,before immunosuppressive therapy,displayed positive anti-HBs and positive antibodies to hepatitis B core antigens (anti-HBc),as markers of resolved HBV infection,and developed hepatitis B surface antigen (HBsAg) and high viraemia with an HBV escape mutant after rituximabbased administration.The sequencing data revealed HBV genotype D with two known escape mutations,P120S.  相似文献   

16.
Offsets, first formalised in the United States of America in the 1970s for wetland mitigation, are now widely used globally with the aim to mitigate loss of biodiversity due to development. Embracing biodiversity offsets is one method of governments to meet their commitments under the Millennium Development Goals and the Convention on Biological Diversity. Resource extraction companies see them as a method of gaining access to land, while the community may perceive them as a way of enhancing environmental outcomes. In New South Wales, Australia, BioBanking legislation was introduced in late 2006 with the aim of ‘no net loss’ of biodiversity associated with development, particularly expanding urban and coastal development. The strengths of the legislation are that it aims to enhance threatened species conservation, and raise the profile of conservation of threatened species and habitats. Weaknesses include (1) the narrowness of the definition of biodiversity; (2) the concepts are based on a flawed logic and immature, imprecise and complex science which results in difficulties in determining biodiversity values; (3) likely problems with management and compliance; and (4) an overall lack of resources for implementation and long-term monitoring. It is concluded that the legislation is a concerted effort to deal with biodiversity loss, however, stakeholders have concerns with the process, and it is unworkable with the complexity of such ecosystems (compared for example to carbon credit trading), and underdeveloped disciplines such as restoration biology and ecology. Despite these criticisms, there is a need for all stakeholders to work to improve the outcomes.  相似文献   

17.
Lein  Etienne  Jordan  Alex 《Hydrobiologia》2021,848(16):3699-3726

The link between the evolution of advanced sociality and cognition has been an important concept across fields and taxonomic boundaries. However, in many study systems, ecological and phylogenetic confounds impair evolutionary inferences drawn when comparing social organization. Here, we highlight the value of the shell-dwelling Lamprologine cichlids of Lake Tanganyika in studies of cognitive and social evolution. These species show differences in social organization, both within and across species, but otherwise exhibit remarkable similarities in their ecology and life history. We focus on the ecological and social attributes of 15 Lamprologine cichlids that live in permanent association with empty gastropod shells, often in syntopy and with largely overlapping ecological niches. We then discuss difficulties with terminology and categorization of social organization, outlining current and emerging methodologies to address these limitations. Our goal is twofold: (i) to gather available empirical evidence on the behaviour, life history, and ecology of shell-dwelling Lamprologine cichlids, highlighting their potential in comparative studies of cognition and evolution, and (ii) to stimulate debate and critical appraisal of current terminology and categorizations of social structure, ideally leading to more precise and empirically standardized definitions of sociality in cichlids.

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