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1.
J Small Anim Pract ; 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38679786

RESUMO

OBJECTIVES: To describe the diagnostic tests used and their comparative performance in dogs diagnosed with sinonasal aspergillosis in the United Kingdom. A secondary objective was to describe the signalment, clinical findings and common clinicopathologic abnormalities in sinonasal aspergillosis. MATERIALS AND METHODS: A multi-centre retrospective survey was performed involving 23 referral centres in the United Kingdom to identify dogs diagnosed with sinonasal aspergillosis from January 2011 to December 2021. Dogs were included if fungal plaques were seen during rhinoscopy or if ancillary testing (via histopathology, culture, cytology, serology or PCR) was positive and other differential diagnoses were excluded. RESULTS: A total of 662 cases were entered into the database across the 23 referral centres. Four hundred and seventy-five cases met the study inclusion criteria. Of these, 419 dogs had fungal plaques and compatible clinical signs. Fungal plaques were not seen in 56 dogs with turbinate destruction that had compatible clinical signs and a positive ancillary test result. Ancillary diagnostics were performed in 312 of 419 (74%) dogs with observed fungal plaques permitting calculation of sensitivity of cytology as 67%, fungal culture 59%, histopathology 47% and PCR 71%. CLINICAL SIGNIFICANCE: The sensitivities of ancillary diagnostics in this study were lower than previously reported challenging the clinical utility of such tests in sinonasal aspergillosis. Treatment and management decisions should be based on a combination of diagnostics including imaging findings, visual inspection, and ancillary testing, rather than ancillary tests alone.

2.
Int J Biometeorol ; 57(3): 391-400, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22710742

RESUMO

In light of heightened interest in the response of pollen phenology to temperature, we investigated recent changes to the onset of Betula (birch) pollen seasons in central and southern England, including a test of predicted advancement of the Betula pollen season for London. We calculated onset of birch pollen seasons using daily airborne pollen data obtained at London, Plymouth and Worcester, determined trends in the start of the pollen season and compared timing of the birch pollen season with observed temperature patterns for the period 1995-2010. We found no overall change in the onset of birch pollen in the study period although there was evidence that the response to temperature was nonlinear and that a lower asymptotic start of the pollen season may exist. The start of the birch pollen season was strongly correlated with March mean temperature. These results reinforce previous findings showing that the timing of the birch pollen season in the UK is particularly sensitive to spring temperatures. The climate relationship shown here persists over both longer decadal-scale trends and shorter, seasonal trends as well as during periods of 'sign-switching' when cooler spring temperatures result in later start dates. These attributes, combined with the wide geographical coverage of airborne pollen monitoring sites, some with records extending back several decades, provide a powerful tool for the detection of climate change impacts, although local site factors and the requirement for winter chilling may be confounding factors.


Assuntos
Betula , Pólen , Clima , Mudança Climática , Inglaterra , Estações do Ano , Temperatura
3.
Plant Biol (Stuttg) ; 17(2): 361-72, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25262794

RESUMO

Rising temperatures and more frequent and severe climatic extremes as a consequence of climate change are expected to affect growth and distribution of tree species that are adapted to current local conditions. Species distribution models predict a considerable loss of habitats for Pinus sylvestris. These models do not consider possible intraspecific differences in response to drought and warming that could buffer those impacts. We tested 10 European provenances of P. sylvestris, from the southwestern to the central European part of the species distribution, for their response to warming and to drought using a factorial design. In this common-garden experiment the air surrounding plants was heated directly to prevent excessive soil heating, and drought manipulation, using a rain-out shelter, permitted almost natural radiation, including high light stress. Plant responses were assessed as changes in phenology, growth increment and biomass allocation. Seedlings of P. sylvestris revealed a plastic response to drought by increased taproot length and root-shoot ratios. Strongest phenotypic plasticity of root growth was found for southwestern provenances, indicating a specific drought adaptation at the cost of overall low growth of aboveground structures even under non-drought conditions. Warming had a minor effect on growth but advanced phenological development and had a contrasting effect on bud biomass and diameter increment, depending on water availability. The intraspecific variation of P. sylvestris provenances could buffer climate change impacts, although additional factors such as the adaptation to other climatic extremes have to be considered before assisted migration could become a management option.


Assuntos
Pinus sylvestris/fisiologia , Plântula/crescimento & desenvolvimento , Adaptação Fisiológica , Biomassa , Mudança Climática , Secas , Ecossistema , Europa (Continente) , Pinus sylvestris/genética , Pinus sylvestris/crescimento & desenvolvimento , Raízes de Plantas/crescimento & desenvolvimento , Caules de Planta/fisiologia , Temperatura
4.
New Phytol ; 140(2): 343-354, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33862852

RESUMO

Whereas much is known of the short-term growth response to elevated atmospheric CO2 concentrations, [CO2 ]elev , there is relatively little information on how the response of native species is modified by temperature, despite the fact that an increase in global mean temperature is expected to accompany the rise in [CO2 ]. In this study, five functionally related annual native species were exposed to different combinations of ambient and elevated [CO2 ] and temperatures in order to assess their response in terms of growth and allometry. Fast-growing annuals were selected for the study because their growth responses could be assessed over a major portion of the plant's life cycle and in as short a period as 8 wk. Plants were grown in eight hemi-spherical glasshouses, programmed to track outside ambient conditions and provide a replicated experimental design. Treatments comprised (i) current ambient [CO2 ] and temperature, (ii) elevated [CO2 ] (ambient+34 kPa), and ambient temperature (iii) ambient [CO2 ] and elevated temperature (ambient+3°C) and (iv) elevated [CO2 ] and elevated temperature (T°Celev ). All five species responded positively to [CO2 ]elev , although the response was statistically significant for only one, Poa annua L. Averaged over all five species, [CO2 ]elev increased total plant biomass by 25% (P=0·005) at 56 d, reflecting a proportionally greater increase in leaf and stem mass relative to root weight. Elevated [CO2 ] had no effect on leaf area, either at the individual species level or overall. Elevated T°C, by contrast, had little effect on shoot growth but increased root mass on average by 43% and leaf area by 22%. Few interactions between elevated [CO2 ] and T°C were observed, with the CO2 response generally greater at elevated than ambient T°C. Both [CO2 ]elev and T°Celev resulted in a transient increase in relative growth rate, (rgr), during the first 14 d exposure and a 3°C increase in temperature had no effect on the duration of the response. CO2 stimulation of growth operated through a sustained increase in net assimilation rate. (nar), although the potential benefit to rgr was offset by a concurrent decline in leaf area ratio (lar), as a result of a decrease in leaf area per unit leaf mass (sla). The response to T°Celev was generally opposite of that to [CO2 ]elev . For example, T°Celev increased lar through an increase in sla and this, rather than any effect on nar, was the major factor responsible for the stimulation of rgr. Allometric analysis of CO2 effects revealed that changes in allocation observed at individual harvests were due solely to changes associated with plant size. Elevated T°C, by contrast, had a direct effect on allocation patterns to leaves, with an increase in leaf area expansion relative to whole plant mass during the initial stages of growth and subsequent increased allocation of biomass away from leaves to other regions of the plant. No change in the allometric relation between roots and shoots were observed at either elevated [CO2 ] or T°C. We conclude, therefore, that allocation of biomass and morphological characteristics such as sla, are relatively insensitive to [CO2 ], at least when analysed at the whole-plant level, and where changes have been observed, these are the product of comparing plants of the same age but different size.

5.
Oecologia ; 105(1): 100-106, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28307128

RESUMO

Distributions of individual bird species in 151 small woods (size range 0.02-30 ha) were investigated in 3 consecutive years during which the abundance of certain species varied markedly. Relationships between the probabilities of certain bird species breeding and woodland area were described using incidence functions derived from logistic regression analysis. In general, for species which were largely dependent on woodland and seldom occurred in other habitats (such as hedgerows and gardens), the probability of breeding approached 100% only for woods of 10 ha and more, whereas species with less stringent habitat requirements occurred in the majority of woods, including those of 1 ha and less. The sensitivity of incidence functions to changes in regional abundance and the size distribution of the study woods was examined. For some species, distribution patterns could not be distinguished from those expected if pairs had been distributed in proportion to woodland area (random placement), but the majority did not conform to random placement in at least 1 of the 3 years. This nonconformity was consistent across all 3 years for some species, such as wren (Troglodytes troglodytes), despite substantial fluctuations in population sizes between years, while for others, such as robin (Erithacus rubecula), distribution patterns changed with changes in regional abundance. The results suggested that some species, such as wren and blackbird (Turdus merula), preferred small woods, while other species, such as chiffchaff (Phylloscopus collybita), preferred large woods. For several other species, including robin, great tit (Parus major), long-tailed tit (Aegithalos caudatus) and marsh tit (P. palustris), small woods appeared to be sub-optimal under at least some conditions.

6.
Oecologia ; 92(1): 130-137, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28311823

RESUMO

Calcium intake by wild rodents varies with season and habitat. This may have important ecological consequences; several studies have suggested that calcium availability may limit growth and reproduction. We studied the effect on growth of varying the calcium intake of captive wood mice Apodemus sylvaticus (L.) and bank voles Clethrionomys glareolus (Schreber 1780). To determine whether effects observed in the laboratory could be detected in free-living animals, we also compared the body weights and lengths of free-living animals on calcium-poor gritstone areas with those of rodents on calcium-rich limestone habitats where the dietary calcium concentration was between 2 and 5 times higher. Captive wood mice fed high calcium (0.87%) diet grew at the same rate as mice fed low calcium (0.30%) diet but continued growing for longer, thereby achieving higher asymptotic weights. In contrast, captive bank voles fed the high calcium diet grew more slowly and had lower asymptotic weights than voles fed the low calcium diet. As expected from the laboratory growth study, the higher calcium intake of free-living wood mice on the limestone was associated with greater body size compared with mice on the gritstone. However, bank voles were also larger on the limestone, even though high calcium intake impaired growth in captive animals. The contrast between wood mice and bank voles in the effects of calcium on growth, the reason why impaired growth may not be apparent in bank voles from calcium-rich habitats and the ecological significance of these results are discussed.

7.
Mutat Res ; 85(3): 133-9, 1981 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7022185

RESUMO

3 Estuarine organisms- oysters (Crassostrea virginica), sea squirts (Mogulla sp.), and shrimp (Peneaus sp.)-were examined for Ames test detectable levels of mutagens. Whole-tissue extracts of these organisms were made and tested using S. Typhimurium strains TA98, TA100, TA1535, TA1537 and TA1538, with and without S9 activation. Positive results were obtained with sea squirts and shrimp extracts. Activation was not necessary to show activity. Toxicity was encountered with oyster extracts. Histidine, a possible source of false positives, was eliminated from shrimp extracts using XAD-2 resin and thick-layer chromatography.


Assuntos
Cordados não Vertebrados/genética , Decápodes/genética , Mutagênicos/análise , Ostreidae/genética , Animais , Testes de Mutagenicidade , Salmonella typhimurium/genética
8.
Science ; 316(5821): 71, 2007 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-17412949

RESUMO

Information on responses of higher organisms to climate change is dominated by events in spring. Far less is known about autumnal events and virtually nothing about communities of microorganisms. We analyzed autumnal fruiting patterns of macrofungi over the past 56 years and found that average first fruiting date of 315 species is earlier, while last fruiting date is later. Fruiting of mycorrhizal species that associate with both deciduous and coniferous trees is delayed in deciduous, but not in coniferous, forests. Many species are now fruiting twice a year, indicating increased mycelial activity and possibly greater decay rates in ecosystems.


Assuntos
Ecossistema , Carpóforos/crescimento & desenvolvimento , Fungos/crescimento & desenvolvimento , Micorrizas/crescimento & desenvolvimento , Inglaterra , Estações do Ano , Temperatura , Fatores de Tempo , Traqueófitas/microbiologia , Árvores/microbiologia
9.
Int J Biometeorol ; 50(5): 275-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16402207

RESUMO

In 1944, John Willis produced a summary of his meticulous record keeping of weather and plants over the 30 years 1913-1942. This publication contains fixed-date, fixed-subject photography taken on the 1st of each month from January to May, using as subjects snowdrop Galanthus nivalis, daffodil Narcissus pseudo-narcissus, horse chestnut Aesculus hippocastanum and beech Fagus sylvatica. We asked 38 colleagues to assess rapidly the plant development in each of these photographs according to a supplied five-point score. The mean scores from this exercise were assessed in relation to mean monthly weather variables preceding the date of the photograph and the consistency of scoring was examined according to the experience of the recorders. Plant development was more strongly correlated with mean temperature than with minimum or maximum temperatures or sunshine. No significant correlations with rainfall were detected. Whilst mean scores were very similar, botanists were more consistent in their scoring of developmental stages than non-botanists. However, there was no overall pattern for senior staff to be more consistent in scoring than junior staff. These results suggest that scoring of plant development stages on fixed dates could be a viable method of assessing the progress of the season. We discuss whether such recording could be more efficient than traditional phenology, especially in those sites that are not visited regularly and hence are less amenable to frequent or continuous observation to assess when a plant reaches a particular growth stage.


Assuntos
Fotografação/métodos , Fenômenos Fisiológicos Vegetais , Clima , Estações do Ano , Temperatura , Fatores de Tempo , Tempo (Meteorologia)
10.
Int J Biometeorol ; 49(4): 262-6, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15538637

RESUMO

Our data, collected in the extreme east of Europe, show that a significant biological effect of climate change has been experienced even in territories where temperature increase has been the lowest. This study documents the climatic response of pedunculate oak (Quercus robur) growing near its north-eastern limits in Europe. It demonstrates the potential of oak trees in old-growth forest to act as proxy climate indicators. Many factors may influence the temporal stability of the growth-climate, acorn crop-climate and first leafing-climate relationships. Climate data, climatic fluctuations, reproduction, genetics and tree-age may relate to this instability. Our results stress that an increase in climate variability or climatic warming resulting from warmer winters or summers could affect the oak population in eastern Europe in a similar way to that in western Europe. These findings, from remnants of oak forest in the middle Volga region of Russia, allow a further understanding of how species could be affected by future climates.


Assuntos
Clima , Quercus/crescimento & desenvolvimento , Aclimatação , Nozes/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Chuva , Federação Russa , Temperatura
11.
Ecotoxicology ; 5(3): 197-207, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24193725

RESUMO

: Resampling techniques for statistical analysis have become increasingly popular in recent years. This paper aims to introduce the reader to some simple applications of resampling methods as applied to ecotoxicological data. Examples of applications in trend detection, comparison of two populations and estimation of population parameters are given. These are compared to results obtained from more familiar methods. Finally, the potential of resampling methods is discussed.

12.
Int J Biometeorol ; 45(4): 212-6, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11769323

RESUMO

The (barn) swallow Hirundo rustica is a traditional harbinger of spring in many countries of the Northern Hemisphere. This paper uses information on the arrival and departure dates of the swallow in the Slovak Republic for the 30 years 1961-1985 and 1996-2000. Records were taken at 19 locations throughout the Republic representing an altitude range from 105 m to 760 m. Monthly temperature data were constructed from six meteorological stations. With the use of regression techniques, trends towards later arrival, earlier departure and the effects of latitude, altitude and temperature are all apparent.


Assuntos
Altitude , Comportamento de Retorno ao Território Vital , Aves Canoras , Temperatura , Adaptação Fisiológica , Animais , Feminino , Masculino , Eslováquia , Fatores de Tempo
13.
Int J Biometeorol ; 45(4): 217-9, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11769324

RESUMO

Many analyses do not consider the problems associated with the effects of population size on encounter recording. Population size could impact on the detection of bird arrival time as there is a higher probability of observing earlier arrival when the population size is greater and the song activity of birds is increased, as occurs with a larger population. As a case study, we have analysed data on the red-backed shrike Lanius collurio collected in Western Poland during 1983-2000. In this period the red-backed shrike's return to its breeding sites became significantly earlier whilst the contemporary population size increased significantly. To eliminate linear trends through time we have worked on the standardised residuals from regression of both arrival time and population size on year. The correlation between arrival time and population size residuals was significantly negative, further supporting the link between detection and population size. This finding suggests that, in studies of avian migration and its changes over time, the relationship between arrival date and population size needs to be considered.


Assuntos
Clima , Comportamento de Retorno ao Território Vital , Aves Canoras , Animais , Dinâmica Populacional , Estações do Ano , Fatores de Tempo
14.
Int J Biometeorol ; 44(2): 82-7, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10993562

RESUMO

This paper examines the mean flowering times of 11 plant species in the British Isles over a 58-year period, and the flowering times of a further 13 (and leafing time of an additional 1) for a reduced period of 20 years. Timings were compared to Central England temperatures and all 25 phenological events were significantly related (P<0.001 in all but 1 case) to temperature. These findings are discussed in relation to other published work. The conclusions drawn from this work are that timings of spring and summer species will get progressively earlier as the climate warms, but that the lower limit for a flowering date is probably best determined by examining species phenology at the southern limit of their distribution.


Assuntos
Clima , Desenvolvimento Vegetal , Temperatura , Monitoramento Ambiental , Estudos Retrospectivos , Reino Unido
15.
Arch Environ Contam Toxicol ; 45(1): 136-47, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12948183

RESUMO

Livers from 121 birds killed in mortality incidents in U.K. coastal waters between 1991 and 1996 were analyzed for 16 PCB congeners (IUPAC numbers 8, 18, 28, 31, 52, 77, 101, 118, 126, 128, 138, 149, 153, 169, 170, and 180). Species analyzed were guillemot (Uria aalge), shag (Phalacrocorax arisotelis), kittiwake (Rissa tridactyla), puffin (Fratercula arctica), razorbill (Alca torda), fulmar (Fulmarus glacialis), gannet (Sula bassana), and herring gull (Larus argentatus). This is the first report of PCBs in U.K. seabird tissues to be presented since 1983. Mean concentrations of total PCBs ranged from 0.47 to 15.8 mg/kg WW, similar to concentrations reported for North Sea birds during the 1970s and 1980s and lower than those reported for the same species in the Irish Sea during the late 1960s and early 1970s. The congeners generally present in the highest concentrations were (in decreasing order) 153, 138, 180, 118, and 170. Despite the birds having similar diets, both inter- and intraspecies differences in PCB congener profile were found. In guillemots from several sites on the east coast, the dominant congener was 138, compared to guillemots from the south coast, which had the more typical congener pattern found in seabirds. Some of the differences in total PCB values could be due to different causes of death, with a subsequent effect on body lipid levels.


Assuntos
Aves , Poluentes Ambientais/farmacocinética , Bifenilos Policlorados/farmacocinética , Animais , Composição Corporal , Causas de Morte , Poluentes Ambientais/análise , Feminino , Lipídeos/análise , Fígado/química , Masculino , Bifenilos Policlorados/análise , Dinâmica Populacional , Reino Unido
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