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41.
Arie J van Noordwijk Gerrit Speek Jacquie A. Clark Zenon Rohde Rinse D. Wassenaar 《Journal of Ornithology》2003,144(4):479-483
The EURING code, which has been the European standard coding system for observations on marked birds, has undergone a major revision and extension resulting in the EURING EXCHANGE CODE 2000. Major aspects of change have a background in computer-technology, a shift in scientific questions and in the interaction between the two. Over the last decades, studies aimed at measuring survival rates and dispersal of individuals have become major questions for bird ringing besides migration research. In these studies one has many observations on the same individual. Therefore, the old code, where each record had a ringing and a finding (dead or alive) part, has been replaced and now each record describes one encounter with the bird. This also facilitates coding all the ringing data, before any subsequent observations have been made. New fields and changed coding make it possible to record many more details about methods used and greater precision of coordinates. The new code specifically allows for recording repeated observations of the same individual arising from other marking systems, such as e.g. radio- or satellite tracking or transponders. The code is freely available and it is hoped that many people will use it, since the future opportunities of using data from different sources that have been coded in the same way are enormous. 相似文献
42.
Catriona A. Morrison Robert A. Robinson Jacquie A. Clark Kate Risely Jennifer A. Gill 《Diversity & distributions》2013,19(8):1051-1058
Aim
Recent, rapid population declines in many Afro‐Palaearctic migratory bird species have focussed attention on changing conditions within Africa. However, processes influencing population change can operate throughout the annual cycle and throughout migratory ranges. Here, we explore the evidence for impacts of breeding and non‐breeding conditions on population trends of British breeding birds of varying migratory status and wintering ecology.Location
Great Britain (England & Scotland).Methods
Within‐ and between‐species variation in population trends is quantified for 46 bird species with differing migration strategies.Results
Between 1994 and 2007, rates of population change in Scotland and England differed significantly for 19 resident and 15 long‐distance migrant species, but were similar for 12 short‐distance migrant species. Of the six long‐distance migrant species that winter in the arid zone of Africa, five are increasing in abundance throughout Britain. In contrast, the seven species wintering in the humid zone of Africa are all declining in England, but five of these are increasing in Scotland. Consequently, populations of both arid and humid zone species are increasing significantly faster in Scotland than England, and only the English breeding populations of species wintering in the humid zone are declining.Main conclusions
Population declines in long‐distance migrants, especially those wintering in the humid zone, but not residents or short‐distance migrants suggest an influence of non‐breeding season conditions on population trends. However, the consistently less favourable population trends in England than Scotland of long‐distance migrant and resident species strongly suggest that variation in the quality of breeding grounds is influencing recent population changes. The declines in humid zone species in England, but not Scotland, may result from poorer breeding conditions in England exacerbating the impacts of non‐breeding conditions or the costs associated with a longer migration, while better conditions in Scotland may be buffering these impacts.43.
KIR2DL2 enhances protective and detrimental HLA class I-mediated immunity in chronic viral infection
Seich Al Basatena NK Macnamara A Vine AM Thio CL Astemborski J Usuku K Osame M Kirk GD Donfield SM Goedert JJ Bangham CR Carrington M Khakoo SI Asquith B 《PLoS pathogens》2011,7(10):e1002270
Killer cell immunoglobulin-like receptors (KIRs) influence both innate and adaptive immunity. But while the role of KIRs in NK-mediated innate immunity is well-documented, the impact of KIRs on the T cell response in human disease is not known. Here we test the hypothesis that an individual's KIR genotype affects the efficiency of their HLA class I-mediated antiviral immune response and the outcome of viral infection. We show that, in two unrelated viral infections, hepatitis C virus and human T lymphotropic virus type 1, possession of the KIR2DL2 gene enhanced both protective and detrimental HLA class I-restricted anti-viral immunity. These results reveal a novel role for inhibitory KIRs. We conclude that inhibitory KIRs, in synergy with T cells, are a major determinant of the outcome of persistent viral infection. 相似文献
44.
Jacquie A. Clark 《Bird Study》2013,60(1):96-102
Capsule The birds that died were generally smaller. Aims To look for selective mortality of waders in severe weather. Methods Biometric measurements of birds found dead in a local severe weather event in February 1991 on The Wash Estuary, UK, were compared with measurements of the same species caught alive in February in previous and following years. Results Eight of 13 intraspecific biometric comparisons between birds found dead and those captured in February in previous years were significantly different. Of these comparisons seven showed that the birds that died were smaller. Three of nine intraspecific biometric comparisons between birds dying during the severe weather and those caught in subsequent years were significant; of these comparisons the dead birds were smaller in two cases. Of eight comparisons between the biometrics of live birds before and after the severe weather event, only one was significant: the bill lengths of Eurasian Oystercatchers Haematopus ostralegus were longer after the event. Conclusions The birds that died due to the severe weather incident do not appear to be a random sample of the populations present. Smaller birds died disproportionately. However, in comparisons of birds captured before and after the severe weather event only Oystercatcher's bill lengths increased significantly and it is unlikely that this was related to the severe weather. Thus, the size‐biased mortality did not result in long‐term changes in the size distributions of the species affected. 相似文献
45.
46.
Banas JA Fountain TL Mazurkiewicz JE Sun K Vickerman MM 《FEMS microbiology letters》2007,275(1):80-88
The glucan-binding protein-A (GbpA) of Streptococcus mutans has been shown to contribute to the architecture of glucan-dependent biofilms formed by this species and influence virulence in a rat model. As S. mutans synthesizes multiple glucosyltransferases and nonglucosyltransferase glucan-binding proteins (GBPs), it is possible that there is functional redundancy that overshadows the full extent of GbpA contributions to S. mutans biology. Glucan-associated properties such as adhesion, aggregation, and biofilm formation were examined independently of other S. mutans GBPs by cloning the gbpA gene into a heterologous host, Streptococcus gordonii, and derivatives with altered or diminished glucosyltransferase activity. The presence of GbpA did not alter dextran-dependent aggregation nor the initial sucrose-dependent adhesion of S. gordonii. However, expression of GbpA altered the biofilm formed by wild-type S. gordonii as well as the biofilm formed by strain CH107 that produced primarily alpha-1,6-linked glucan. Expression of gbpA did not alter the biofilm formed by strain DS512, which produced significantly lower quantities of parental glucan. These data are consistent with a role for GbpA in facilitating the development of biofilms that harbor taller microcolonies via binding to alpha-1,6-linkages within glucan. The magnitude of the GbpA effect appears to be dependent on the quantity and linkage of available glucan. 相似文献
47.
Catriona A. Morrison Stephen R. Baillie Jacquie A. Clark Alison Johnston David I. Leech Robert A. Robinson 《Ibis》2015,157(2):340-350
Higher temperatures resulting from climate change have led to predictions that the duration of the breeding season of many temperate bird species may be changing. However, the extent to which breeding seasons can be altered will also depend on the degree of flexibility in processes occurring at other points in the annual cycle. In particular, plasticity in the timing of post‐breeding moult (PBM) could facilitate changes in the timing of key events throughout the annual cycle, but little is known about the level of within‐ and between‐species plasticity in PBM. As part of the British Trust for Ornithology (BTO) Ringing Scheme, many ringers routinely record moult scores of flight feathers, and these can be used to provide information on the annual progression of PBM for a range of species. Here we use ringing data to investigate patterns of PBM in 15 passerines, as well as data from the BTO Nest Record Scheme to relate these differences to the timing of breeding of these species across the UK. We find considerable variation in both the mean start (19 May–29 July) and duration (66–111 days) of PBM between species, but find no evidence that species starting PBM later in the season complete it any faster. However, there is considerable within‐species variation in PBM, particularly for multi‐brooded species; PBM starts later and is completed in less time when the duration of the breeding season (difference between first and last nests) is longer. This implies that a later end to breeding can be compensated for by faster PBM, and that advances in breeding could lead to earlier and slower PBM. Our findings suggest that adaptation of PBM in response to climate‐mediated changes in the timing and duration of the breeding season is possible. However, the requirement to complete PBM prior to migration or the onset of winter might constrain the extent to which breeding seasons can lengthen, especially for later nesting species. 相似文献
48.
A total of 17 linking clones previously sublocalized to the central span of the mouse X chromosome have been ordered by detailed analysis through interspecific Mus spretus/Mus musculus domesticus backcross progeny. These probes have been positioned with respect to existing DNA markers utilizing a new interspecific backcross segregating for the Tabby (Ta) locus. The density of clones within this 11.5-cM interval is now, on average, one clone every 1000 kb. This high-density map provides probes in the vicinity of a number of important genetic loci in this region which include the X-inactivation center, the Ta locus, and the mottled (Mo) locus, and therefore provides a molecular framework for identification of the genes encoded at these loci. 相似文献
49.
50.
Warren R Hsiao WW Kudo H Myhre M Dosanjh M Petrescu A Kobayashi H Shimizu S Miyauchi K Masai E Yang G Stott JM Schein JE Shin H Khattra J Smailus D Butterfield YS Siddiqui A Holt R Marra MA Jones SJ Mohn WW Brinkman FS Fukuda M Davies J Eltis LD 《Journal of bacteriology》2004,186(22):7783-7795
Rhodococcus sp. strain RHA1, a potent polychlorinated-biphenyl (PCB)-degrading strain, contains three linear plasmids ranging in size from 330 to 1,100 kb. As part of a genome sequencing project, we report here the complete sequence and characterization of the smallest and least-well-characterized of the RHA1 plasmids, pRHL3. The plasmid is an actinomycete invertron, containing large terminal inverted repeats with a tightly associated protein and a predicted open reading frame (ORF) that is similar to that of a mycobacterial rep gene. The pRHL3 plasmid has 300 putative genes, almost 21% of which are predicted to have a catabolic function. Most of these are organized into three clusters. One of the catabolic clusters was predicted to include limonene degradation genes. Consistent with this prediction, RHA1 grew on limonene, carveol, or carvone as the sole carbon source. The plasmid carries three cytochrome P450-encoding (CYP) genes, a finding consistent with the high number of CYP genes found in other actinomycetes. Two of the CYP genes appear to belong to novel families; the third belongs to CYP family 116 but appears to belong to a novel class based on the predicted domain structure of its reductase. Analyses indicate that pRHL3 also contains four putative "genomic islands" (likely to have been acquired by horizontal transfer), insertion sequence elements, 19 transposase genes, and a duplication that spans two ORFs. One of the genomic islands appears to encode resistance to heavy metals. The plasmid does not appear to contain any housekeeping genes. However, each of the three catabolic clusters contains related genes that appear to be involved in glucose metabolism. 相似文献