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81.
J.S. Rowan J. Carwardine R.W. Duck O.M. Bragg A.R. Black M.E.J. Cutler I. Soutar P.J. Boon 《水产资源保护:海洋与淡水生态系统》2006,16(6):637-657
- 1. In the absence of a standard procedure for characterizing the physical habitat of lakes in Europe, this paper describes the development of a multi‐purpose Lake Habitat Survey (LHS). The technique has been designed to meet the hydromorphological assessment needs of the Water Framework Directive (WFD), as well as to assist in monitoring the condition of designated sites in the UK and for wider application in environmental impact assessments and restoration programmes.
- 2. LHS involves detailed recording of shoreline features at a number of plots (Hab‐Plots), complemented by a meso‐scale survey of the entire lake, including shoreline characteristics and pressures, and modifications to the hydrological regime. A temperature and dissolved oxygen profile is also compiled at the deepest point of the lake (Index Site). Existing databases are exploited where possible, and remote sensing data (e.g. aerial photographs) are used to assist field‐based observations.
- 3. Initial field trials demonstrated that the consistency of the method, whether conducted by boat or on foot, was high. More than 250 surveys were carried out across the UK in 2004 through collaboration with the statutory environment and conservation agencies.
- 4. Two levels of complexity were tested — a full version requiring 10 Hab‐Plots and an abridged version, LHScore, involving four plots and omitting the Index Site. While 8–10 plots were required to capture the full diversity of features at complex sites, LHScore data were sufficient to generate metrics for classification purposes.
- 5. A Lake Habitat Modification Score (LHMS) may be calculated from LHS data. This synthesizes a wide array of hydromorphological and human pressures and has direct applications for assessment of ecological status under the WFD. Preliminary analysis illustrates a spectrum of hydromorphological alteration of 82 lakes in the UK.
- 6. Further considerations are discussed, including the prospect that the LHS protocol might form the basis of a European standard developed through CEN (Comité Européen de Normalisation).
82.
The geological record of ocean acidification 总被引:1,自引:0,他引:1
Hönisch B Ridgwell A Schmidt DN Thomas E Gibbs SJ Sluijs A Zeebe R Kump L Martindale RC Greene SE Kiessling W Ries J Zachos JC Royer DL Barker S Marchitto TM Moyer R Pelejero C Ziveri P Foster GL Williams B 《Science (New York, N.Y.)》2012,335(6072):1058-1063
Ocean acidification may have severe consequences for marine ecosystems; however, assessing its future impact is difficult because laboratory experiments and field observations are limited by their reduced ecologic complexity and sample period, respectively. In contrast, the geological record contains long-term evidence for a variety of global environmental perturbations, including ocean acidification plus their associated biotic responses. We review events exhibiting evidence for elevated atmospheric CO(2), global warming, and ocean acidification over the past ~300 million years of Earth's history, some with contemporaneous extinction or evolutionary turnover among marine calcifiers. Although similarities exist, no past event perfectly parallels future projections in terms of disrupting the balance of ocean carbonate chemistry-a consequence of the unprecedented rapidity of CO(2) release currently taking place. 相似文献
83.
IMAGING DIAGNOSIS—COMPUTED TOMOGRAPHY FINDINGS IN A CASE OF METASTATIC OVARIAN ADENOCARCINOMA IN A DOG
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Conor Rowan Laura Cuddy Jill Bryan Robert Shiel Séamus Hoey 《Veterinary radiology & ultrasound》2017,58(6):E60-E63
A 5‐year‐old female entire German Shepherd presented for otitis and lethargy. An incidental abdominal mass was identified on examination. Ultrasound examination (US) identified a heterogeneous left ovarian mass. Computed tomography (CT) was performed for surgical planning and staging. The reproductive tract was removed en bloc and submitted for histopathology. Multiple small (1–5 mm) nodules identified at coeliotomy on the surface of the liver, spleen and peritoneum were biopsied. The lesions were not visible on CT nor US on review. This is the first case report of the CT findings of ovarian papillary adenocarcinoma with carcinomatosis. 相似文献
84.
- 1. A method has been developed for assessing the degree of human alteration of river flow regimes relative to near‐natural or reference conditions.
- 2. The Dundee Hydrological Regime Alteration Method (DHRAM) utilizes the Indicators of Hydrologic Alteration approach of the US Nature Conservancy to classify the risk of damage to in‐stream ecology using a five‐class scheme compatible with the requirements of the EC Water Framework Directive.
- 3. Separate methods have been developed for rivers and lakes, though only the former are considered in this paper.
- 4. DHRAM uses daily mean flow time‐series data, representing un‐impacted and impacted situations for the site of interest, in relation to any type of anthropogenic hydrological impact such as impoundments, abstractions or flow augmentation.
- 5. Procedures for coping with different levels of data availability are outlined, utilizing the Micro Low Flows computer package to generate synthetic series of daily mean flows, supplemented by flow alteration data as appropriate.
- 6. The utility of DHRAM is demonstrated through a pair of Scottish case studies illustrating its ability in classifying regime alteration and supporting mapping, which will be of value to river basin managers.
- 7. Finally, present and future issues relating to the calibration of DHRAM scores to levels of ecological damage are discussed.
85.
Cruz Cardona JA Milner R Alleman AR Williams C Vernau W Breen M Tompkins M 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2011,40(1):40-47
A 9-year-old female spayed mixed breed dog was evaluated at the University of Florida Small Animal Hospital for marked leukocytosis with no associated clinical signs. CBC abnormalities included marked leukocytosis (106,000/μL), marked monocytosis (78,000/μL), and the presence of 13% blast cells (13,832/μL), supporting a diagnosis of leukemia. Cytopenias and dysplastic changes in other cell lines were not present. Microscopic examination of bone marrow showed hypercellular uniparticles with a marginal increase in frequency of unclassified blast cells (2%), but was otherwise unremarkable. Flow cytometric immunophenotyping of blood cells determined that leukemic cells were CD45(+) , CD14(+) , and CD34(-) , and based on side scatter and CD45 reactivity the marrow contained 19% monoblasts. By immunocytochemical staining, the leukemic cells in the bone marrow were CD11b(+) , CD11c(+) , CD11d(+) , MHC-II(+) , MPO(+) , and CD34(-) . Fluorescence in situ hybridization (FISH) analysis of peripheral blood leukocytes documented a chromosomal translocation producing a BCR-ABL gene hybrid, similar to the "Philadelphia" chromosome abnormality recognized in human chronic myelogenous leukemia, as well as a phosphatase and tensin homolog (PTEN) gene deletion. Hydroxyurea therapy was attempted, but was ineffective; the dog died 7 months after initial presentation. Clinical and laboratory findings and the protracted course supported a diagnosis of chronic monocytic leukemia (CMoL) and, to our knowledge, this is the first case of CMoL with a BCR-ABL chromosomal abnormalitiy described in dogs. This may have clinical implications for treatment of dogs with chronic leukemias associated with particular genetic mutations. However, more case studies are needed to further characterize this disease. 相似文献
86.
87.
M M Mansour J B Dixon T G Rowan S D Carter 《Veterinary immunology and immunopathology》1992,33(3):261-269
The effects of Ostertagia ostertagi infection and diet on antibody responses to O. ostertagi third stage larval (L3) antigen and to an unrelated antigen, Keyhole Limpet Haemocyanin (KLH) were determined in calves experimentally infected with 3000 L3 on alternate days for 6 weeks. Calves were given one of two diets, and were either infected or not infected with O. ostertagi L3. The diets were either high (H) or low (L) in protein/energy and were within the range of normal husbandry practice in the UK. Both IgG1 and IgG2, but not IgA, responses to L3 antigen were increased in the L-diet compared with the H-diet. IgA responses to L3 antigen were not affected by dietary treatment. The effects of diet and infection on anti-KLH IgG1 were independent of each other; IgG1 anti-KLH responses were decreased by infection and by the L-diet compared with the H-diet. The data suggest that there is a strong interrelationship between diet and immunity during nematode infections. 相似文献
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Experimental estimates of the effects of selection on genes determining adaptive traits add to our understanding of the mechanisms of evolution. We measured selection on genotypes of the Ectodysplasin locus, which underlie differences in lateral plates in threespine stickleback fish. A derived allele (low) causing reduced plate number has been fixed repeatedly after marine stickleback colonized freshwater from the sea, where the ancestral allele (complete) predominates. We transplanted marine sticklebacks carrying both alleles to freshwater ponds and tracked genotype frequencies over a generation. The low allele increased in frequency once lateral plates developed, most likely via a growth advantage. Opposing selection at the larval stage and changing dominance for fitness throughout life suggest either that the gene affects additional traits undergoing selection or that linked loci also are affecting fitness. 相似文献