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51.
An integrative approach for analysing landscape dynamics in diverse cultivated and natural mountain areas 总被引:3,自引:1,他引:2
Our landscape can be regarded as a development process that is affected and subsequently shaped by a series of different environmental
and human-induced factors. However, to date, concrete data about the impact of each of these factors are still missing. One
key reason for this is that methods of acquisition and evaluation of these factors inherently have differences, thereby preventing
meaningful comparative analyses. This study presents an integrative methodical approach that bridges many of these gaps. Our
approach also has the advantages of being generally applicable while delivering easily interpretable results that also allow
comparisons between diverse geographical regions. The indicators used enable all major features of landscape change, e.g.
changes in land use, landscape structuring, habitat settings, and urban sprawl, to be accurately monitored and provide high-quality
realistic results that were validated in our study site, South Tyrol (North Italy). Indicators were selected for both their
further subdivision, e.g. monocrops and different features of mixed crops, and their easy to ascertain hierarchically structured
feature classification, e.g. land cover. Furthermore, our use of ecoregions enables better comparison of aspects of landscape
development for geographical regions having diverse socio-economic and ecological conditions. Our methodical approach can
be used as a basis not only for creating landscape change scenarios, but also for determining the environmental and human-induced
factors involved and being able to list them in order of importance. Further the detected striking difference between the
mapped land-use data and the official census data suggests a validation of the methodical approach in context of the national
agriculture census. 相似文献
52.
53.
Falk R. Rittig Rainer Becker Hermann Bleiholder Franz Feichtmayr Erich Haedicke Judith B. St. John 《Pest management science》1983,14(3):299-302
Substituted pyridazinones induced specific decreases in the linolenic acid content accompanied by increases in the linoleic acid content of plant membranes. The ratio of linoleic acid to linolenic acid was used to establish structure-activity correlations for a series of about 50 different substituted pyridazinones. The most active compound found was 4-chloro-5-dimethylamino-2-phenylpyridazin-3-one. X-ray structural analysis of this compound yielded three types of crystals differing in their molecular parameters. Application of computerised cluster analysis confirmed the specific biological activity of selected groups of compounds. Electron-density calculations yielded substituents with specific activity on the linoleic acid/linolenic acid ratio. Correlation of this ratio, produced by different substituted pyridazinones, can be used to search for potentially more active compounds. Treatment of plants, moulds and insects with pyridazinones led to interesting results of importance to agriculture, and confirmed the bioregulator activity of some of these compounds. 相似文献
54.
55.
Erich Spoor Laura Stainback Scott Plummer Kim Knowles 《Veterinary radiology & ultrasound》2019,60(1):47-55
The neurological examination findings, clinical pathology (including Coccidioides immitis IgG/IgM serology) and magnetic resonance imaging (MRI) findings in 13 dogs with a novel form of intracranial coccidioidomycosis are described in a retrospective case series, with long‐term clinical resolution documented in 11/13 dogs (84.6% of cases) with oral fluconazole therapy. The medical records of the Veterinary Neurological Center in Phoenix, Arizona from the years 2000 to 2017 were utilized to search for dogs with appropriate inclusion criteria. Magnetic resonance imaging findings were highly consistent across all cases and characteristically demonstrated bilaterally symmetric T2 hyperintensity throughout the frontal lobes, caudate nuclei, and rostral internal capsule, ±faint, wispy contrast enhancement on T1‐postcontrast images. These findings were in stark contrast to previously reported MRI findings in dogs with intracranial coccidioidomycosis, which were typically characterized by a focal, strongly contrast enhancing granuloma and extensive vasogenic edema, typically unilateral. Schnauzer breeds represented eight of 13 (61.5%) cases, possibly suggesting a breed predilection. Three cases underwent repeat MRI after resolution of neurological signs and documentation of a decreased Coccidioides titer in response to fluconazole therapy. All demonstrated complete resolution of previously identified lesions, but with marked, severe atrophy of the caudate nuclei and frontal lobes bilaterally. Findings from this study document a variant appearance for intracranial coccidioidomycosis that, to the author's knowledge, has not been previously described in dogs. Authors propose that, although this variant demonstrates extensive pathological changes within the forebrain, the clinical outcome and response to treatment is favorable in a majority of cases. 相似文献
56.
57.
Large-scale sequence analysis of avian influenza isolates 总被引:1,自引:0,他引:1
Obenauer JC Denson J Mehta PK Su X Mukatira S Finkelstein DB Xu X Wang J Ma J Fan Y Rakestraw KM Webster RG Hoffmann E Krauss S Zheng J Zhang Z Naeve CW 《Science (New York, N.Y.)》2006,311(5767):1576-1580
The spread of H5N1 avian influenza viruses (AIVs) from China to Europe has raised global concern about their potential to infect humans and cause a pandemic. In spite of their substantial threat to human health, remarkably little AIV whole-genome information is available. We report here a preliminary analysis of the first large-scale sequencing of AIVs, including 2196 AIV genes and 169 complete genomes. We combine this new information with public AIV data to identify new gene alleles, persistent genotypes, compensatory mutations, and a potential virulence determinant. 相似文献
58.
The degree of phosphorus saturation (DPS) has been shown to be a suitable initial indicator of P loss potential from agricultural
soils to surface waters. In addition, several agronomic soil tests have been evaluated as environmental predictive tools.
The objectives of this study were: (1) to evaluate the modified Morgan soil test, used on acid, high-aluminum soils of the
northeastern United States, as a predictor of water-soluble P and (2) to determine the effect of soil organic matter (SOM)
on the ability of both DPS and soil test P to predict water-soluble P. The soils were divided into three SOM classifications
depending on their loss-on-ignition contents and analyzed for water-soluble P, modified Morgan soil test P, and oxalate-extractable
P, Al, and Fe. The relationship between DPS and water-soluble P showed a change point at about 15% DPS, as did the relationship
between DPS and modified Morgan soil test P. A DPS of 15% corresponded to about 14 mg kg−1, a threshold above which water-soluble P could be expected to increase more rapidly with additional P loading. The slopes
of the regression lines of water-soluble P as a function of soil test P were 0.050, 0.036, and 0.021 (mg water-soluble P kg−1 soil/mg soil test P kg−1) for the low, medium, and high SOM classification groups, respectively. SOM level had a less significant effect on the relationship
between DPS and water-soluble P. Higher levels of SOM were associated with higher levels of oxalate-extractable Fe and Al
and, therefore, higher P sorption capacities and lower DPS values, resulting in less P in solution at all soil test levels. 相似文献
59.
Many arctic mammals are adapted to live year-round in extreme environments with low winter temperatures and great seasonal variations in key variables (e.g. sunlight, food, temperature, moisture). The interaction between hosts and pathogens in high northern latitudes is not very well understood with respect to intra-annual cycles (seasons). The annual cycles of interacting pathogen and host biology is regulated in part by highly synchronized temperature and photoperiod changes during seasonal transitions (e.g., freezeup and breakup). With a warming climate, only one of these key biological cues will undergo drastic changes, while the other will remain fixed. This uncoupling can theoretically have drastic consequences on host-pathogen interactions. These poorly understood cues together with a changing climate by itself will challenge host populations that are adapted to pathogens under the historic and current climate regime. We will review adaptations of both host and pathogens to the extreme conditions at high latitudes and explore some potential consequences of rapid changes in the Arctic. 相似文献
60.
Neumann S Stolt P Braun G Hellmann K Reinhart E 《Journal of the American Animal Hospital Association》2011,47(1):12-20
The authors compared the symptomatic effectiveness of a complex homeopathic preparation Zeel (1-3 tablets orally per day depending on body weight) to carprofen (4 mg/kg body weight) in dogs (n=68) aged >1 yr diagnosed with osteoarthritis in a multicenter, prospective, observational open-label cohort study in 12 German veterinary clinics. The active treatment period was 56 days. Symptomatic effectiveness, lameness, stiffness of movements, and pain on palpation were evaluated by treating veterinarians and owners. Clinical signs of osteoarthritis improved significantly (P<0.05) at all time points (days 1, 28, and 56) with both therapies. At the end of the treatment period, effectiveness was comparable in both groups. Both treatment regimens were well tolerated with only three treatment-related adverse events, all in the carprofen group. 相似文献