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1.
The debated identity of a small forest bushbaby in Malawi is resolved by a short-term field study of the animals’ behavior.
Locomotor styles, calling patterns, and the structure of advertising calls confirm that the species is Galago zanzibaricusrather than G. demidoffor G. thomasi.A detailed comparison of acoustic structure between the Malawi animals and G. zanzibaricusin Kenya demonstrates a degree of between-population variation, although the calls remain conservative in those parameters
expected to aid recognition of conspecifics. Distribution records extend the known geographical range of G. zanzibaricusover most of the northern half of Malawi. Further studies are required to link the animals from this region with either of
the previously recognized subspecies: G. z. zanzibaricusfrom East Africa or G. z. grantifrom southern Malawi, Mozambique, and Zimbabwe. 相似文献
2.
Effects of environmental factors on ichthyoplankton communities in the Miramichi estuary, Gulf of St Lawrence 总被引:2,自引:0,他引:2
Ichthyoplankton in 20 taxa (17 identified to species, threeto genus) representing 14 families were collected in 10 surveysof the Miramichi estuary between May and September 1992. Thetaxonomic composition was typical of other estuaries in theGulf of St Lawrence and Gulf of Maine. Larvae of three anadromousspecies [rainbow smelt (Osmerus mordax), alewife (Alosa pseudoharengus)and blueback herring (Alosa aestivalis)] were several ordersof magnitude more abundant than any other taxon. The upper estuary(Miramichi River and its tributaries) probably serves as a nurseryground for larvae of these species and others such as Atlantictomcod (Microgadus tomcod). The species composition of the lowerestuary (Miramichi Bay) was dominated by typically marine formsand probably serves as a nursery ground for winter flounder(Pleuronectes americanus), smooth flounder (Pleuronectes putnami).sculpin (Myoxocephalus sp ) and sand lance (Ammodytes sp) Ofthe environmental factors investigated, salinity was the mostuseful predictor of larval distribution in the estuary. 相似文献
3.
Laura Willen Maria-Gloria Basez Vit Dvorak Francis B. D. Veriegh Frank T. Aboagye Bright Idun Maha Elhadi Osman Mike Y. Osei-Atweneboana Orin Courtenay Petr Volf 《PLoS neglected tropical diseases》2021,15(6)
BackgroundSimulium damnosum sensu lato (s.l.) blackflies transmit Onchocerca volvulus, a filarial nematode that causes human onchocerciasis. Human landing catches (HLCs) is currently the sole method used to estimate blackfly biting rates but is labour-intensive and questionable on ethical grounds. A potential alternative is to measure host antibodies to vector saliva deposited during bloodfeeding. In this study, immunoassays to quantify human antibody responses to S. damnosum s.l. saliva were developed, and the salivary proteome of S. damnosum s.l. was investigated.Methodology/Principal findingsBlood samples from people living in onchocerciasis-endemic areas in Ghana were collected during the wet season; samples from people living in Accra, a blackfly-free area, were considered negative controls and compared to samples from blackfly-free locations in Sudan. Blackflies were collected by HLCs and dissected to extract their salivary glands. An ELISA measuring anti-S. damnosum s.l. salivary IgG and IgM was optimized and used to quantify the humoral immune response of 958 individuals. Both immunoassays differentiated negative controls from endemic participants. Salivary proteins were separated by gel-electrophoresis, and antigenic proteins visualized by immunoblot. Liquid chromatography mass spectrometry (LC–MS/MS) was performed to characterize the proteome of S. damnosum s.l. salivary glands. Several antigenic proteins were recognized, with the major ones located around 15 and 40 kDa. LC–MS/MS identified the presence of antigen 5-related protein, apyrase/nucleotidase, and hyaluronidase.Conclusions/SignificanceThis study validated for the first time human immunoassays that quantify humoral immune responses as potential markers of exposure to blackfly bites. These assays have the potential to facilitate understanding patterns of exposure as well as evaluating the impact of vector control on biting rates. Future studies need to investigate seasonal fluctuations of these antibody responses, potential cross-reactions with other bloodsucking arthropods, and thoroughly identify the most immunogenic proteins. 相似文献
4.
Functional traits have long been considered the ‘holy grail’ in community ecology due to their potential to link phenotypic variation with ecological processes. Advancements across taxonomic disciplines continue to support functional ecology's objective to approach generality in community assembly. However, a divergence of definitions, aims and methods across taxa has created discord, limiting the field's predictive capacity. Here, we provide a guide to support functional ecological comparisons across taxa. We describe advances in cross‐taxa functional research, identify gaps in approaches, synthesize definitions and unify methodological considerations. When deciding which traits to compare, particularly response traits, we advocate selecting functionally analogous traits that relate to community assembly processes. Finally, we describe at what scale and for which questions functional comparisons across taxa are useful and when other approaches may be more constructive. Our approach promotes standardized methods for integrative research across taxa to identify broad trends in community assembly. 相似文献
5.
The impact of cold-water immersion on power production in the vertical jump and the benefits of a dynamic exercise warm-up 总被引:1,自引:0,他引:1
Dixon PG Kraemer WJ Volek JS Howard RL Gomez AL Comstock BA Dunn-Lewis C Fragala MS Hooper DR Häkkinen K Maresh CM 《Journal of strength and conditioning research / National Strength & Conditioning Association》2010,24(12):3313-3317
The purpose of this study was to examine the influence of a cold treatment and a dynamic warm-up on lower body power in the form of a countermovement vertical jump (CMVJ). Nine physically active men, who were either current or ex-National Collegiate Athletic Association (NCAA) Division 1 athletes, consented to participate in the study. Using a balanced, randomized presentation and a within-subject design, each subject performed 4 environmental and warm-up protocols (i.e., ambient temperature without warm-up, ambient temperature with warm-up, cold without warm-up, or cold with warm-up). Two sets of 3 maximal effort CMVJs were performed on a force plate at each testing time point. For each protocol, the subjects completed a pretest set of CMVJ (pretreatment [PRE]), were then exposed to 1 of the 2 temperature treatments, completed another set of CMVJ (initial [IT]), then either went through a 15-minute warm-up, or were asked to sit in place. Then a final set of CMVJs was completed (posttreatment [PT]). The primary finding in this study was that warm-up was effective in offsetting the negative effects of cold exposure on CMVJ power. There was a significant main effect for Time (PRE > PT > IT), and there was a significant (p ≤ 0.05) main effect for Trial (AMB = AMBWU > COLDWU > COLD). Because athletic competitions happen in various colder climates, it is important to make sure that a proper warm-up be completed to maximize the athlete's power output. The results of this study demonstrate that when athletes are exposed to cold conditions, it is recommended that before practice or play, a dynamic warm-up be employed to optimize performance. 相似文献
6.
Deltamethrin-impregnated bednets reduce human landing rates of sandfly vector Lutzomyia longipalpis in Amazon households 总被引:1,自引:0,他引:1
Courtenay O Gillingwater K Gomes PA Garcez LM Davies CR 《Medical and veterinary entomology》2007,21(2):168-176
The entomological efficacy of using 25% deltamethrin EC insecticide-treated bednets (ITNs) was evaluated against the sandfly Lutzomyia longipalpis Lutz and Neiva (Diptera: Psychodidae), the principal vector of zoonotic visceral leishmaniasis (ZVL) in Latin America. A crossover field study in Amazon Brazil (Marajó Island, Pará State) demonstrated that, compared with untreated nets, the insecticide increased the barrier effect of nets by 39% (95% confidence interval [CI] 34-44%), reduced human landing rates by 80% (95% CI 62-90%) and increased the 24-h mortality rate from 0% to 98% (95% CI 93-99%) inside ITNs. The presence of an ITN also reduced the human landing rate on unprotected persons outside the net in the same room by 56% (95% CI 52-59%), and increased 24-h mortality to 68% (95% CI 62-73%) compared to 0.4% (0.1-2.0%) in untreated houses. The reduction in human landing rates in ITN rooms was associated with a doubling in the proportion of sandflies alighting on walls compared with that in untreated rooms, which was attributed to insecticide-induced excito-repellency. There was no evidence that sandflies were diverted onto unprotected hosts. Human landing catches inside houses peaked between 19.00 hours and 23.00 hours and declined steadily to zero at 02.00 hours and thereafter. House-to-house questionnaires established that only 34% of households owned at least one net (median two, range 1-8), only 20% of the population slept under a net (33% of 0-5-year-old children), and the majority (73%) of the population slept in hammocks. Combined data pertaining to sleeping times for children and sandfly activity period indicate that > 50% of sandfly bites inside houses, and substantially more outside houses, were taken before a third of children were potentially protected by a net. This study demonstrates the clear entomological efficacy of ITNs against Lu. longipalpis in this endemic region. The effectiveness of ITNs at preventing ZVL infection and disease has still to be evaluated. 相似文献
7.
Environmental Monitoring of Mycobacterium bovis in Badger Feces and Badger Sett Soil by Real-Time PCR, as Confirmed by Immunofluorescence, Immunocapture, and Cultivation
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F. P. Sweeney O. Courtenay V. Hibberd R. G. Hewinson L. A. Reilly W. H. Gaze E. M. H. Wellington 《Applied microbiology》2007,73(22):7471-7473
Real-time PCR was used to detect and quantify Mycobacterium bovis cells in naturally infected soil and badger feces. Immunomagnetic capture, immunofluorescence, and selective culture confirmed species identification and cell viability. These techniques will prove useful for monitoring M. bovis in the environment and for elucidating transmission routes between wildlife and cattle. 相似文献
8.
Travis ER Gaze WH Pontiroli A Sweeney FP Porter D Mason S Keeling MJ Jones RM Sawyer J Aranaz A Rizaldos EC Cork J Delahay RJ Wilson GJ Hewinson RG Courtenay O Wellington EM 《PloS one》2011,6(11):e27369
Advances in the diagnosis of Mycobacterium bovis infection in wildlife hosts may benefit the development of sustainable approaches to the management of bovine tuberculosis in cattle. In the present study, three laboratories from two different countries participated in a validation trial to evaluate the reliability and reproducibility of a real time PCR assay in the detection and quantification of M. bovis from environmental samples. The sample panels consisted of negative badger faeces spiked with a dilution series of M. bovis BCG Pasteur and of field samples of faeces from badgers of unknown infection status taken from badger latrines in areas with high and low incidence of bovine TB (bTB) in cattle. Samples were tested with a previously optimised methodology. The experimental design involved rigorous testing which highlighted a number of potential pitfalls in the analysis of environmental samples using real time PCR. Despite minor variation between operators and laboratories, the validation study demonstrated good concordance between the three laboratories: on the spiked panels, the test showed high levels of agreement in terms of positive/negative detection, with high specificity (100%) and high sensitivity (97%) at levels of 10(5) cells g(-1) and above. Quantitative analysis of the data revealed low variability in recovery of BCG cells between laboratories and operators. On the field samples, the test showed high reproducibility both in terms of positive/negative detection and in the number of cells detected, despite low numbers of samples identified as positive by any laboratory. Use of a parallel PCR inhibition control assay revealed negligible PCR-interfering chemicals co-extracted with the DNA. This is the first example of a multi-laboratory validation of a real time PCR assay for the detection of mycobacteria in environmental samples. Field studies are now required to determine how best to apply the assay for population-level bTB surveillance in wildlife. 相似文献
9.
Sweeney FP Courtenay O Ul-Hassan A Hibberd V Reilly LA Wellington EM 《Letters in applied microbiology》2006,43(4):364-369
AIMS: To adapt an immunomagnetic capture (IMC) technique to concentrate and cultivate Mycobacterium bovis from environmental samples including soil, faeces and urine. METHODS AND RESULTS: Cells of Myco. bovis BCG and wild-type Myco. bovis were successfully isolated and cultured from seeded and naturally infected materials respectively. The IMC cell recovery estimated by colony forming units (CFUs) counts ranged from 0.10% to 0.16% for spiked media, and 0.15-0.36% for naturally infected soil and faeces. Recovery estimated by cell counts calculated using semi-quantitative PCR ranged from 80.3% to 88.6% for spiked and 84.1-88.2% for naturally infected material. The differences in the recovery rates estimated by CFUs compared with pixel intensity is likely to be due to clustering of cells on culture plates, thereby underestimating the true cell count. CONCLUSIONS: The IMC techniques can be applied to isolate viable wild type Myco. bovis from naturally contaminated environmental samples. SIGNIFICANCE AND IMPACT OF STUDY: Cultivation of Myco. bovis from environmental samples using traditional methods is extremely problematic. Here, we demonstrate a novel development of IMC techniques that will greatly facilitate the study of the organism in situ in order to assess its epidemiological importance in bovine tuberculosis persistence. 相似文献
10.