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81.
With this paper we initiate a taxonomic review of the genusNapaeus from the Canary Islands, indicating the statisticalmethodology used therein. We discuss the taxonomic problem ofNapaeus (Napaeinus) nanodes (Shuttleworth, 1852), designateits lectotype and describe five new species: Napaeus (Napaeinus)doliolum Henríquez, Napaeus (Napaeinus) bechi Alonso& Ibáñez, Napaeus (Napaeus) taguluchensisHenríquez, Napaeus (Napaeus) pygmaeus Ibáñez& Alonso and Napaeus (Napaeus) tagamichensis Henríquez,the first two from Tenerife; and the other three from La Gomera.Furthermore, we discuss the general relationships of the genusand its two sub-genera, whose original diagnoses are deficient;because of this, we think that in the future a broad reviewof the subfamily Eninae will be necessary in order to clarifythe actual position of this subfamily in the Canary Islands. (Received 11 March 1991; accepted 22 September 1992)  相似文献   
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1. Varroa destructor Linnaeus (Acari: Varroidae) is one of the greatest threats to apiculture. This study examines the role of host density, natural resource availability for bees, the management and climate in driving spatial and annual variability in the abundance of Varroa, and the occurrence of colony losses, recorded in apiaries across a Mediterranean island over a 2‐year period, using a hierarchical generalised linear model framework. 2. The seasonal abundance of Varroa showed a bimodal pattern with two peaks, the first one being in spring and larger than the second one located in summer/autumn. In contrast, bee colony losses were mainly concentrated in autumn/winter. 3. The abundance patterns of Varroa were best explained by models combining host, climate, and resource availability. A key novel finding was that low availability of natural flowering resources leads to high levels of infestation of Varroa, highlighting the importance of preserving natural resources around apiaries for the maintenance of pollination services in the landscape. Varroa abundance was also found to increase as bee density increased, probably as a result of the greater brood availability. Moreover, Varroa abundance increased as temperatures decrease and decreases as relative humidity increases, which is consistent with previous studies. Anti‐varroa treatments were only found to impact Varroa levels in the second 6 months of the year. Organic treatments outperformed synthetic treatments. 4. Empirical research on optimal seasonal timing and combinations of treatments, as well as impacts of climate and resource availability on natural dynamics of bees and Varroa in different climate zones, is urgently required.  相似文献   
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Plant virus diseases constitute one of the limiting factors to the productivity of agriculture. Changes in host plants and insect vector populations that might result from climate change (their geographical distribution range, their densities, migration potential and phenology) could affect the spread of plant viruses. At the individual level, alterations in plant physiological processes that are relevant to their molecular interactions with viruses, like changes in metabolism, leaf temperature, and their effects on some processes, like the temperature-sensitive antiviral resistance based in RNA silencing, can also influence the ability of individual plants to control viral infections. In order to assess the impact that climate change may have on the incidence and spread of hemipteran-borne plant viruses, its potential effects on virus/plant interactions and hemipteran insect vectors, as well as other operating processes, which could exacerbate or mitigate them, are identified and analyzed in this review.  相似文献   
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Thirteen juvenile Golden Eagles Aquila chrysaetos were tracked during their first year of life using satellite telemetry. Distances to the nest attained during that period and the age at the onset of juvenile dispersal were explored. The performance of nine different criteria to determine that age was analysed. In general, after a brief period of restricted movements around the nest, the average distance to the nest increased with time. Maximum distances to the nest ranged between 57.7 and 184.3 km, and were considerably greater in females (mean ± sd, 138.5 ± 44.5 km) than in males (70.5 ± 14.0 km). No sex difference was observed in the age at which that distance was attained (males: 329 ± 32 days, females: 312 ± 20 days). The onset of juvenile dispersal took place around the fifth month of life (September in Spain). Eight of the nine criteria provided similar results, suggesting that in Spain dispersal starts when birds are between 140 and 180 days old, and that the post-nestling period lasts between 60 and 120 days. For future studies, to determine the age at which the onset of juvenile dispersal occurs, we recommend the use of either the first day on which individuals were located beyond the mean distance between nests of different pairs (10 km in our study area), or the date of the record midway between the first and the last location recorded during the month in which the maximum variability in the distance to the nest was observed.  相似文献   
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In 2009 the WPA President established a Task Force that was to examine available evidence about the stigmatization of psychiatry and psychiatrists and to make recommendations about action that national psychiatric societies and psychiatrists as professionals could do to reduce or prevent the stigmatization of their discipline as well as to prevent its nefarious consequences. This paper presents a summary of the Task Force’s findings and recommendations. The Task Force reviewed the literature concerning the image of psychiatry and psychiatrists in the media and the opinions about psychiatry and psychiatrists of the general public, of students of medicine, of health professionals other than psychiatrists and of persons with mental illness and their families. It also reviewed the evidence about the interventions that have been undertaken to combat stigma and consequent discrimination and made a series of recommendations to the national psychiatric societies and to individual psychiatrists. The Task Force laid emphasis on the formulation of best practices of psychiatry and their application in health services and on the revision of curricula for the training of health personnel. It also recommended that national psychiatric societies establish links with other professional associations, with organizations of patients and their relatives and with the media in order to approach the problems of stigma on a broad front. The Task Force also underlined the role that psychiatrists can play in the prevention of stigmatization of psychiatry, stressing the need to develop a respectful relationship with patients, to strictly observe ethical rules in the practice of psychiatry and to maintain professional competence.  相似文献   
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Variation at five polymorphic microsatellite loci was used to investigate genetic diversity and differentiation of two tetraploid Canarian endemics, Bencomia exstipulata and B. caudata. Data were analysed and are discussed in terms of tetrasomic (autotetraploid) and disomic (allotetraploid) inheritance. In both cases, genetic diversity values were similar to those described in other tetraploid plant species. High genetic differentiation between the only two described natural populations of B. exstipulata was detected (FST = 0.411). Bayesian cluster analysis revealed a geographical structure with distinct genetic groups from each island. High genetic differentiation and low genetic diversity of the B. exstipulata population from Tenerife suggest a recent population bottleneck, perhaps caused by the most recent major volcanic eruption, for this natural locality. This may be heightened by possible inbreeding depression and the monoecy of these species. Polymorphic microsatellite loci were also tested across all species in the Bencomia alliance. These reliably amplified the target sequence, suggesting a high degree of conservation of the sequences flanking the microsatellites. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 160 , 429–441.  相似文献   
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Exposure to chronic stress early on during development has important deleterious consequences later in life, reducing important components of individual fitness such as survival and future reproduction. In this study, we evaluate the factors associated with physiological response to stress in fledgling Lesser Kestrels Falco naumanni , paying particular attention to the potential role of individual genetic diversity. For this purpose, we used heterophil/lymphocyte ratios (H/L ratio) as a haematological stress indicator and typed the analysed individuals at 11 highly polymorphic microsatellite loci, which allowed us to estimate their genetic diversity. We found that the H/L ratio decreases with fledgling physical condition, suggesting that this parameter is a good indicator of nutritionally based physiological stress. Physiological response to stress was higher in males than in females and this effect was independent of physical condition, suggesting that the observed pattern is due to inherent sexual differences in the factors influencing H/L ratios. Finally, the H/L ratio was positively associated with the genetic diversity of offspring. Previous experimental studies have found that individuals with higher genetic diversity show increased levels of circulating glucocorticoids, which in turn are directly responsible for increasing H/L ratios. On this basis, we suggest that a positive effect of genetic diversity on corticosterone levels may explain the observed association between H/L ratios and individual heterozygosity. Overall, this study highlights the utility of leucocyte profiles to study stress in wild bird populations and poses an interesting question about the effects of individual genetic diversity on haematological response to stress.  相似文献   
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