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1.
The box tree moth, Cydalima perspectalis (Walker) (Lepidoptera: Crambidae), a native pest of box trees (Buxus spp.) in Asia, was first detected in Germany and the Netherlands in 2007 and has since rapidly spread throughout Europe causing severe damage to ornamental and native box trees. To date, sustainable control strategies for C. perspectalis in Europe are lacking, primarily owing to the inadequate information regarding the biology and the ecology of this recent invader. Several studies conducted in Asia, however, may provide important information for the development of management strategies against C. perspectalis, which are urgently needed to preserve the natural box tree forests in Europe. The current literatures on the biological characteristics, host plants, phenology, distribution and control options of the box tree moth in Asia are reviewed, preliminary data on the parasitism of C. perspectalis in Europe are provided, and options for sustainable long‐term solutions for the management of the invasive pest in Europe are discussed.  相似文献   

2.
The concept of vulnerability is deployed in bioethics to, amongst other things, identify and remedy harms to participants in research, yet although nonhuman animals in experimentation seem intuitively to be vulnerable, this concept and its attendant protections are rarely applied to research animals. I want to argue, however, that this concept is applicable to nonhuman animals and that a new taxonomy of vulnerability developed in the context of human bioethics can be applied to research animals. This taxonomy does useful explanatory work, helping to pinpoint the limitations of the 3Rs/welfare approach currently adopted in the context of animal experimentation. On this account, the 3Rs/welfare approach fails to deliver for nonhuman animals in experimentation because it effectively addresses only one element of their vulnerability (inherent) and paradoxically through the institution of Animal Ethics Committees intended to protect experimental animals in fact generates new vulnerabilities that exacerbate their already precarious situation.  相似文献   

3.
The authors review the evidence for the evolution of the apes and their geographical expansion out of Africa during the Miocene. The ecological background is discussed at each period.From this it is concluded that Dryopithecines in either Africa or Eurasia could have given rise to early Hominidae and that the ecological conditions in both continents were suitable for the appearance of Hominid adaptations.The evidence for early Hominids is at present more impressive in Eurasia than in Africa, though the African find from Fort Ternan, Kenya, is the earliest. On present evidence, neither continent can be precluded as the place of origin of the Hominidae and it appears to be a possibility that Hominidae evolved in both continents with intermittent gene exchange.  相似文献   

4.
Intelligence is suggested to have evolved in primates in response to complexities in the environment faced by their ancestors. Corvids, a large-brained group of birds, have been suggested to have undergone a convergent evolution of intelligence [ Emery & Clayton (2004) Science , Vol. 306, pp. 1903–1907 ]. Here we review evidence for the proposal from both ultimate and proximate perspectives. While we show that many of the proposed hypotheses for the evolutionary origin of great ape intelligence also apply to corvids, further study is needed to reveal the selective pressures that resulted in the evolution of intelligent behaviour in both corvids and apes. For comparative proximate analyses we emphasize the need to be explicit about the level of analysis to reveal the type of convergence that has taken place. Although there is evidence that corvids and apes solve social and physical problems with similar speed and flexibility, there is a great deal more to be learned about the representations and algorithms underpinning these computations in both groups. We discuss recent comparative work that has addressed proximate questions at this level, and suggest directions for future research.  相似文献   

5.
The possibility thatHomo crossed the Gibraltar Strait during the Plio-Pleistocene is currently debated. The finds of human remains and lithic artefacts in different Plio-Pleistocene beds of the Orce region (SE Iberia Peninsula) are evidence thatHomo was in this region at least before 1.4 mya. But, which was the route used byHomo to reach SE Spain during the early Pleistocene? In this contribution we collect different kinds of data (paleontological, geological, paleogeographical, paleoclimatic and oceanographic) which strengthen the hypothesis thatHomo crossed the Gibraltar Strait for the first time during earliest Pleistocene. Important falls in sea level related to cold periods together with the presence in the Iberian Peninsula of African mammal species at different times in the geological history and also the presence of at least one European species in North Africa during the Late Pliocene indicate a faunal exchange between Africa and Europe. The geography of the strait, the marine currents and their possible evolution are questions treated in this contribution. Some fossils and current examples of mammal fauna migrations across the sea are also analysed.  相似文献   

6.
We report a case of a 34-year-old Polish Caucasian male who was diagnosed with tinea manuum caused by Trichophyton rubrum var. raubitschekii. It would be the first described case of a dermatophytosis caused by this fungus in Poland and one of a few cases in Central Europe described so far. Admittedly, it would be the first case in Central Europe with no evidence pointing to African origin. The clinical condition improved after administering itraconazole (daily dose 100 mg orally) supplemented with a topical treatment, while the patient was totally cured after 2 months. The histopathological examination turned out to be highly useful in the diagnostic process. The genetic analysis of the urease gene pointed to a urease-positive T. rubrum rather than T. rubrum var. raubitschekii.  相似文献   

7.
As well as being phytohormones, gibberellins (GAs) are present in some fungi and bacteria. Indeed, GAs were first discovered in the fungus Gibberella fujikuroi, from which gibberellic acid (GA3) and other GAs are produced commercially. Although higher plants and the fungus produce structurally identical GAs, there are important differences in the pathways and enzymes involved. This has become particularly apparent with the identification of almost all of the genes for GA-biosynthesis in Arabidopsis thaliana and G. fujikuroi, following the sequencing of the Arabidopsis genome and the detection of a GA-biosynthesis gene cluster in the fungus. For example, 3b-hydroxylation occurs early in the pathway in G. fujikuroi and is catalyzed by a cytochrome P450 monooxygenase, whereas it is usually the final step in plants and is catalyzed by 2-oxoglutarate-dependent dioxygenases. Similarly, 20-oxidation is catalyzed by dioxygenases in plants and a cytochrome P450 in the fungus. Even where cytochrome P450s have equivalent functions in plants and Gibberella, they are unrelated in terms of amino acid sequence. These profound differences indicate that higher plants and fungi have evolved their complex biosynthetic pathways to GAs independently and not by horizontal gene transfer.  相似文献   

8.
Resin producing agroforestry in the Krui area of Sumatra in Indonesia is presented as an environmentally friendly, income generating land-use system which contributes to both development and conservation objectives. We studied the change in household income portfolios in three communities in the Krui area. The studies revealed that in the period 1995–2004 agroforestry remained the main source of income. We predict, however, that due to declining resin productivity per hectare, and rising price and demand for timber, an increasing number of farmers will cut their mature agroforests in the near future. At the same time our data suggests that farmers will continue tree planting activities. In result old agroforests may vanish while new ones will be established.
Koen KustersEmail:
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9.
Equality of opportunity theories distinguish between inequalities due to individual effort and those due to external circumstances. Recent research has shown that half of the variability in income of World population was determined by country of birth and income distribution. Since health and income are generally strictly related, the aim of this paper is to estimate how much variability in income and health is determined by external circumstances. We use data from the Survey of Health, Ageing and Retirement (SHARE) and the English Longitudinal Survey on Ageing (ELSA), two comparable multidisciplinary surveys that provide micro-level data on health and financial resources among the elderly for a large number of European countries. Our baseline estimation shows that about 20% of the variability in income is explained by current country-specific circumstances, while health outcomes range from 12% using BMI to 19% using self-rated health. By including early-life circumstances, the explained variability increases almost 20 percentage points for income and for self-rated health but less for other health outcomes. Finally, by controlling for endogeneity issues linked with effort, our estimates indicate that circumstances better explain variability in health outcomes. Results are robust to some tests, and the implications of these findings are discussed.  相似文献   

10.
After a recall of the recent emergence of the great ecological problems on the scale of the European continent and of the privileged use of vegetation maps as an ecological tool, a cartographic synthesis of the main plant formations in Europe is submitted on the basis of a hierarchized and numerized nomenclature of the vegetation units. Examples of connections between vegetation and ecology, as suggested or facilitated by this map, are given: use of the monthly ombrothermic diagrams as a privileged tool, thermic limits of the boreal zone, indicative value of the Mediterranean xerothermic area, predictive models of the geographical shifts of the great ecosystems according to the expected climate changes.  相似文献   

11.
A Century of B Chromosomes in Plants: So What?   总被引:3,自引:0,他引:3  
BACKGROUND: Supernumerary B chromosomes (Bs) are a major source of intraspecific variation in nuclear DNA amounts in numerous species of plants. They favour large genomes, and create polymorphisms for DNA variation in natural populations. By studying Bs we can gain useful knowledge about the organization, function and evolution of genomes. There are also significant biological questions concerning the origin and structural organization of Bs, and the way in which these selfish elements can establish themselves by exploiting the replicative machinery of their host genome nucleus. SCOPE: It is a sine qua non that Bs originate from the A chromosomes, in a variety of ways. We can study their modes of drive and ask how it is that chromosomes which apparently lack genes can have control over their own drive process which leads to their survival in natural populations. Molecular cytogenetic studies are opening up new avenues of investigation. Population equilibria for B frequencies are determined by a balance between accumulation and harmful effects. Bs are also subject to meiotic loss due to polysomy and to elimination at meiosis as univalents. These balancing forces can be seen in the context of host/parasite interaction, based on a dissection of the genetic elements in both As and Bs (in maize) which interact to bring about a stable equilibrium, at least for a snapshot in time. CONCLUSIONS: Aside from their intrinsic enigmatic properties, B chromosomes make useful experimental tools to study genome organization. Thus far they have not been exploited for their applications, other than through the use of A-B translocations used for gene mapping in maize; but there are opportunities to use them to modulate the frequency and distribution of recombination, to diploidize allopolyploids, to study centromeres and to be developed as plant artificial chromosomes; given that they can be structurally modified and their inheritance stabilized.  相似文献   

12.
Common reed die-back is a widely investigated phenomenon in Central Europe, not frequently recorded in S-European areas and almost unknown in the Mediterranean Basin. Symptoms of reed decline recently observed in the Italian Peninsula provided the starting point for a detailed investigation on a reed population in one of the largest freshwater ecosystems in Central Italy. The analyses were conducted over two vegetative seasons in 19 plots at seven locations. A set of 13 morphologic and phenologic reed traits were screened, monitored and statistically analysed. The data indicated the presence of the reed die-back syndrome in a wet Mediterranean ecosystem and enabled us to highlight a set of usable traits to detect the condition of decline. Among them, the stem height and diameter, the number of nodes, the relative growth rate and the lateral root diameter resulted the most significant factors highlighting the declining condition. Some environmental characteristics of the reed stands were also taken into account. The period of submersion and the presence of standing litter emerged as important features of the stands, strictly related to the degree of decline in the population. The results draw attention to the risk, in southern Europe too, of the loss of an ecosystem which plays an important role in biodiversity conservation.  相似文献   

13.
14.
Summary The distribution of phenotypic and allelic frequencies of red blood cells aminolevulinate dehydrase in several Italian populations is reported. The frequency of the most common allele ALADH1 ranges from 0.78 to 0.93 with a mean value of 0.90±0.01.  相似文献   

15.
16.
Pneumocystis fungi represent a highly diversified biological group with numerous species, which display a strong host-specificity suggesting a long co-speciation process. In the present study, the presence and genetic diversity of Pneumocystis organisms was investigated in 203 lung samples from woodmice (Apodemus sylvaticus) collected on western continental Europe and Mediterranean islands. The presence of Pneumocystis DNA was assessed by nested PCR at both large and small mitochondrial subunit (mtLSU and mtSSU) rRNA loci. Direct sequencing of nested PCR products demonstrated a very high variability among woodmouse-derived Pneumocystis organisms with a total number of 30 distinct combined mtLSU and mtSSU sequence types. However, the genetic divergence among these sequence types was very low (up to 3.87%) and the presence of several Pneumocystis species within Apodemus sylvaticus was considered unlikely. The analysis of the genetic structure of woodmouse-derived Pneumocystis revealed two distinct groups. The first one comprised Pneumocystis from woodmice collected in continental Spain, France and Balearic islands. The second one included Pneumocystis from woodmice collected in continental Italy, Corsica and Sicily. These two genetic groups were in accordance with the two lineages currently described within the host species Apodemus sylvaticus. Pneumocystis organisms are emerging as powerful tools for phylogeographic studies in mammals.  相似文献   

17.
Psychoanalytic theory appears flawed in the way it has been traditionally applied in anthropological studies of spirit possession in South Asia. It is suggested that pathological spirit possession in South Asia has a similar etiology to multiple personality disorder in North America, which is caused by spontaneous trance reactions to extreme situations in the environment, particularly child abuse. Reanalyses of previously published case histories of spirit possession illnesses in South Asia are presented from the perspective of dissociation theory, highlighting possible etiology not considered relevant in earlier psychoanalytic theories.  相似文献   

18.
On the basis of comprehensive RFLP analysis, it has been inferred that approximately 97% of Native American mtDNAs belong to one of four major founding mtDNA lineages, designated haplogroups "A"-"D." It has been proposed that a fifth mtDNA haplogroup (haplogroup X) represents a minor founding lineage in Native Americans. Unlike haplogroups A-D, haplogroup X is also found at low frequencies in modern European populations. To investigate the origins, diversity, and continental relationships of this haplogroup, we performed mtDNA high-resolution RFLP and complete control region (CR) sequence analysis on 22 putative Native American haplogroup X and 14 putative European haplogroup X mtDNAs. The results identified a consensus haplogroup X motif that characterizes our European and Native American samples. Among Native Americans, haplogroup X appears to be essentially restricted to northern Amerindian groups, including the Ojibwa, the Nuu-Chah-Nulth, the Sioux, and the Yakima, although we also observed this haplogroup in the Na-Dene-speaking Navajo. Median network analysis indicated that European and Native American haplogroup X mtDNAs, although distinct, nevertheless are distantly related to each other. Time estimates for the arrival of X in North America are 12,000-36,000 years ago, depending on the number of assumed founders, thus supporting the conclusion that the peoples harboring haplogroup X were among the original founders of Native American populations. To date, haplogroup X has not been unambiguously identified in Asia, raising the possibility that some Native American founders were of Caucasian ancestry.  相似文献   

19.
Nipah virus (NiV) (Genus Henipavirus) is a recently emerged zoonotic virus that causes severe disease in humans and has been found in bats of the genus Pteropus. Whilst NiV has not been detected in Australia, evidence for NiV-infection has been found in pteropid bats in some of Australia’s closest neighbours. The aim of this study was to determine the occurrence of henipaviruses in fruit bat (Family Pteropodidae) populations to the north of Australia. In particular we tested the hypothesis that Nipah virus is restricted to west of Wallace’s Line. Fruit bats from Australia, Papua New Guinea, East Timor and Indonesia were tested for the presence of antibodies to Hendra virus (HeV) and Nipah virus, and tested for the presence of HeV, NiV or henipavirus RNA by PCR. Evidence was found for the presence of Nipah virus in both Pteropus vampyrus and Rousettus amplexicaudatus populations from East Timor. Serology and PCR also suggested the presence of a henipavirus that was neither HeV nor NiV in Pteropus alecto and Acerodon celebensis. The results demonstrate the presence of NiV in the fruit bat populations on the eastern side of Wallace’s Line and within 500 km of Australia. They indicate the presence of non-NiV, non-HeV henipaviruses in fruit bat populations of Sulawesi and Sumba and possibly in Papua New Guinea. It appears that NiV is present where P. vampyrus occurs, such as in the fruit bat populations of Timor, but where this bat species is absent other henipaviruses may be present, as on Sulawesi and Sumba. Evidence was obtained for the presence henipaviruses in the non-Pteropid species R. amplexicaudatus and in A. celebensis. The findings of this work fill some gaps in knowledge in geographical and species distribution of henipaviruses in Australasia which will contribute to planning of risk management and surveillance activities.  相似文献   

20.
Temperature has a strong effect on the seasonal timing of life-history stages in both mammals and birds, even though these species can regulate their body temperature under a wide range of ambient temperatures. Correlational studies showing this effect have recently been supported by experiments demonstrating a direct, causal relationship between ambient temperature and seasonal timing. Predicting how endotherms will respond to global warming requires an understanding of the physiological mechanisms by which temperature affects the seasonal timing of life histories. These mechanisms, however, remain obscure. We outline a road map for research aimed at identifying the pathways through which temperature is translated into seasonal timing.  相似文献   

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