Comparison of magnetic resonance imaging sequences in dogs with multi-focal intracranial disease

OBJECTIVES: To compare the value of different magnetic resonance sequences in the detection of brain lesions in dogs with multi-focal intracranial neurolocalised lesions and abnormal cisternal cerebrospinal fluid analysis. METHODS: T2-weighted, T1-weighted, T1-weighted-Gd, FLAIR (fluid attenuated inversion recovery) images of 73 dogs with multi-focal intracranial localised lesions were reviewed retrospectively. Control dogs (19) were selected on the basis of normal neurological examination, magnetic resonance images and cerebrospinal fluid analysis. Two board-certified radiologists blindly reviewed the magnetic resonance images. Magnetic resonance sequence sensitivities were compared using the chi-squared test and logistic regression, accounting for clustering at the patient level. Statistical significance was set at the 5 per cent level. RESULTS: The FLAIR sequence was found to have the highest sensitivity (84 per cent, 61 of 73), followed by T2-weighted (63 per cent, 46 of 73), T1-weighted postcontrast (62 per cent, 45 of 73) and T1-weighted (23 per cent, 17 of 73) (P<0.001). FLAIR images were 106.1 times (95 per cent confidence interval 25.2 to 447.5) more likely to correctly identify cerebrospinal fluid-positive patients than T1-weighted, 6.4 times (95 per cent confidence interval 2.2 to 18.2) than T1-weighted postcontrast and 5.8 times (95 per cent confidence interval 2.0 to 16.4) than T2-weighted. FLAIR identified 14 per cent of cases that were classified as normal based on the three others sequences. CLINICAL SIGNIFICANCE: Routine use of FLAIR sequence should be encouraged in dogs undergoing a brain magnetic resonance imaging and probably more specifically in cases of suspected inflammatory brain disease.     

沙棘油脂

果实 沙棘果实由果肉（68%）、种子（23%）和果皮（7.75%）组成（Zadernowski et al.,1997）.Yang和Kallio（2001）最近发现,从中国、芬兰和前苏联（FSU）等地大量选择后采集的沙棘果实中23%～28%是种子,72%～77%是柔软的果肉/果皮.沙棘果实可提取3种油：种子油、果肉油和果皮油.不同于其他植物,沙棘果实的各部分都能合成并积累脂肪.有时果肉油和果皮油没有区别,因此统称为果实油或果肉油.沙棘叶也含油,这部分内容将在稍后部分进一步说明.     

Preference for and performance of some Australian native plants grown as hedges

Indigenous and other native plants are commonly restricted to informal or naturalistic designed landscapes. This research project investigates the use of native plants as a formal landscape element – the hedge. A multidisciplinary approach was used with distinct horticultural and social science components. The first study explored the response of 14 native and one exotic species to hedging every 4 months. Digital imaging techniques were used to measure changes in growth, density and canopy distribution. All species responded well to hedging, greatly increasing in density. Significant differences in growth rates and shoot regrowth patterns were recorded between the species. Some hedges grown from genetically diverse plant material had noticeable morphological variations and would be more suited to use as informal hedges, however growth rates were found to be a much better predictor of hedging performance than genetic uniformity. A second study explored gardeners’ (n=162) preference for these native hedges. Photomontages were created of the hedges grown in the horticultural experiment and a photo-questionnaire distributed to several groups of gardeners. The preference results showed that many gardeners did like some Australian plants used as hedges. Significant differences in preference were found between species. A principal components analysis found that factors positively affecting preference for hedges included neatness, foliage colour (green and grey), presence of flowers and the absence of visible woody stems. In general, genetically diverse hedges were slightly less preferred than genetically uniform hedges, but some genetically diverse hedges were highly preferred. Personal style preferences based on gardeners’ expressed gardening behaviour were also observed, with grey and softer hedges preferred by those participants with low-maintenance, drought tolerant or native gardens.     

Catching invasive Chinese mitten crabs while releasing the endangered European eel and other fish by‐catch: The implications of fyke net design

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Evaluation of poultry fat and blends of poultry fat with cold‐pressed flaxseed oil as supplemental dietary lipid sources for juvenile sablefish (Anoplopoma fimbria)

The objective of this study was to access the suitability of using poultry fat (PF) or blends of PF with flaxseed oil (FO) to replace 75% of the supplemental anchovy oil (AO) in the diet of juvenile sablefish (Anoplopoma fimbria), a relatively new marine species to aquaculture. Sablefish were fed one of four diets twice daily to satiation for 15 weeks. The test diets were identical in composition except for the source of supplemental lipid which was either 100% AO (100AO), or had 75% of the supplemental AO replaced with 50% FO:25% PF, 25% FO:50% PF or 75% PF. Sablefish growth parameters, whole body and fillet proximate constituent concentrations, and apparent digestibility coefficients were uninfluenced by diet treatment. There were also no adverse effects of the diet treatments on fish health, as determined from analysis of various haematological and innate immunological parameters. Terminal fillet fatty acid compositions generally reflected the dietary fatty acid compositions. Results indicated that PF or blends of PF and FO may comprise 75% of the supplemental lipid in a grower diet for sablefish and are an economic alternative to AO while still providing humans with a rich dietary source of highly unsaturated fatty acids.     

Impact of biodiversity-climate futures on primary production and metabolism in a model benthic estuarine system

Background

A territory as a prerequisite for breeding limits the maximum number of breeders in a given area, and thus lowers the proportion of breeders if population size increases. However, some territorially breeding animals can have dramatic density fluctuations and little is known about the change from density-dependent processes to density-independence of breeding during a population increase or an outbreak. We suggest that territoriality, breeding suppression and its break-down can be understood with an incomplete-control model, developed for social breeders and social suppression.

Results

We studied density dependence in an arvicoline species, the bank vole, known as a territorial breeder with cyclic and non-cyclic density fluctuations and periodically high densities in different parts of its range. Our long-term data base from 38 experimental populations in large enclosures in boreal grassland confirms that breeding rates are density-regulated at moderate densities, probably by social suppression of subordinate potential breeders. We conducted an experiment, were we doubled and tripled this moderate density under otherwise the same conditions and measured space use, mortality, reproduction and faecal stress hormone levels (FGM) of adult females. We found that mortality did not differ among the densities, but the regulation of the breeding rate broke down: at double and triple densities all females were breeding, while at the low density the breeding rate was regulated as observed before. Spatial overlap among females increased with density, while a minimum territory size was maintained. Mean stress hormone levels were higher in double and triple densities than at moderate density.

Conclusions

At low and moderate densities, breeding suppression by the dominant breeders, But above a density-threshold (similar to a competition point), the dominance of breeders could not be sustained (incomplete control). In our experiment, this point was reached after territories could not shrink any further, while the number of intruders continued to increase with increasing density. Probably suppression becomes too costly for the dominants, and increasing number of other breeders reduces the effectiveness of threats. In wild populations, crossing this threshold would allow for a rapid density increase or population outbreaks, enabling territorial species to escape density-dependency.