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51.
Michael Lynch Helen McCracken Ronald Slocombe 《Journal of zoo and wildlife medicine》2002,33(3):263-271
Three adult red pandas (Ailurus fulgens) developed multiple periarticular exostoses in their elbow joints. Two of these animals also had extensive periosteal new bone formation and osteosclerosis of the ulnae and radii and mild periosteal new bone deposition on the femurs. One animal also showed extensive hyperostosis of the cranium and mandibles. Dietary concentrations of calcium and phosphorus were estimated to be adequate, but dietary vitamin A and D appeared excessive when compared with recommended levels for this species. Serum vitamin A concentrations were not elevated in the two most severely affected animals, but their liver vitamin A content was higher than what is considered normal for most domestic animal species. Serum 25-hydroxy vitamin D concentrations were within normal ranges for domestic species. A definitive diagnosis for the cause of the lesions was not established, but hypervitaminosis A was suspected. 相似文献
52.
Abstract. Native woodland restoration is a conservation priority within the UK and there is an increasing awareness that a long-term strategy is required to guide this process. A GIS-based modelling approach has been developed, which links site conditions as expressed in an integrated soil and land cover dataset with the site requirements for different woodland types. There are three important aspects to the model – the parameter weightings, the added value of the integrated dataset, and the woodland categories which are described and predicted. The initial quantitative and qualitative validation has been encouraging although more is required and planned. The results indicate that for broad strategic planning purposes, predictions of woodland potential are not improved significantly when climatic factors are incorporated. The concept that soil acts as an integrator of other environmental variables is discussed alongside the practical application of the model by a range of users. 相似文献
53.
54.
Summary The appearance of bracts through the surface of the cauliflower curd had a heritability estimate of 0.73 ± 0.10 based on the regression of progeny on parent when grown under field conditions. When curds were taken from field grown plants and aseptically cultured, their bracting characteristics were enhanced. It is advocated that a two-tier system of selection, firstly in the field and then in culture, would increase the likelihood of breeding bract free cauliflowers.Also, Department of Biological Sciences, The Polytechnic, Hatfield, Hertfordshire, UK. 相似文献
55.
4月1日,澳大利亚开始对“恐龙植物”——瓦勒迈杉(WollemiPine)进行解禁,开放销售,很快,其他国家陆续开始引进瓦勒迈杉。瓦勒迈杉属南洋杉科,是世界最古老的物种之一,与恐龙同时出现在侏罗纪时代,距今已有将近两亿年。以前考古学家曾多次找到过该树种的化石。不过,长期以来人们 相似文献
56.
Summary Cauliflowers representing those maturing in Britain in autumn, winter and spring were assessed for self-compatibility by self-pollen tube growth. A tendency existed for groups taking longer to mature to be more self-incompatible, but a range of incompatibilities was apparent in all groups. These results complement those of other workers.It is argued that despite demonstrable heterosis within many groups of cauliflowers, radical advances are probably best made by selecting self-compatible material from annual × biennial hybrid populations. 相似文献
57.
Amrein TM Lukac H Andres L Perren R Escher F Amadò R 《Journal of agricultural and food chemistry》2005,53(20):7819-7825
The influences of composition and roasting conditions on acrylamide formation in almonds and hazelnuts were investigated. Eighteen samples of almonds originating from the U.S. and Europe were analyzed for sugars and free amino acids, and acrylamide formed during roasting was determined. Asparagine was the main free amino acid in raw almonds and correlated with the acrylamide content of dark roasted almonds. Roasting temperature was another key factor and had a very strong influence on acrylamide formation. Almonds of European origin contained significantly less free asparagine and formed significantly less acrylamide during roasting as compared to the almonds from the U.S. Roasted hazelnuts contained very little acrylamide because of the low content of free asparagine in the raw nut. Reducing sugars, although being consumed much faster than free amino acids in both types of nuts, were not decisive for the extent of acrylamide formation during roasting. 相似文献
58.
Woffenden HM Ames JM Chandra S Anese M Nicoli MC 《Journal of agricultural and food chemistry》2002,50(17):4925-4933
Pale malts were prepared using standard and rapid kilning regimes that differed in the temperature and moisture profiles in the kiln. Samples were taken over the last 9 h of kilning, that is, at 18, 20, 22, 25, and 27 h. Antioxidant activity, assessed by redox potential, scavenging of the 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS*+), and ferric reducing/antioxidant power (FRAP), increased at moisture levels below 6.7% for both regimes. The 27 h malt exposed to the rapid regime (moisture content of 4.8%) had a higher activity than the 27 h standard regime sample (moisture content of 4.8%). None of the malts scavenged oxygen. Pro-oxidant activity profiles were different for the malts obtained using each regime and, at 27 h, the rapid procedure gave malt with higher activity. Levels of (+)-catechin and ferulic acid (the most abundant phenolic compounds identified) generally increased as the moisture content of malt fell below 6.7%. Differences in antioxidant and pro-oxidant activities of the 27 h malts are partly attributed to the Maillard reaction, as evidenced by lower L* and higher b* values and higher levels of Maillard-derived flavor compounds, in the sample obtained by the rapid procedure. Levels of lipid-derived flavor compounds were significantly higher after 27 h of kilning using the rapid procedure. 相似文献
59.
Avison SJ Gray DA Davidson GM Taylor AJ 《Journal of agricultural and food chemistry》2001,49(1):270-275
Supercritical fluids can extract components from some matrixes (e.g., fat and flavors from food) as well as infusing additives into synthetic polymer matrixes. To study the feasibility of infusing flavors into matrixes as a potential flavoring mechanism, a wide range of volatile flavor compounds was infused into a well-defined synthetic polymer (low-density polyethylene) using supercritical carbon dioxide. The polymer was then extracted, and the amount of infused compound was determined. The effects of time, temperature, pressure, rate of depressurization, volatile concentration, and volatile properties on the degree of infusion were studied. Infusion with supercritical carbon dioxide achieved much higher loadings of the polymer (0.01 to 6.87 mg/g LDPE, depending on the volatile molecule being infused) compared to those achieved by static diffusion. Forty-five volatiles were infused, from which a model was developed to predict infusion as a function of certain physicochemical properties. 相似文献
60.
Helen J. Foster Matthew J. Lees Howard S. Wheater Colin Neal Brian Reynolds 《Water, air, and soil pollution》2001,130(1-4):1283-1288
Concern about acidification in upland areas has brought about the need to model the stream hydrochemical response to deposition and land-use changes and calculate critical loads. Application of dynamic models such as MAGIC are preferable to steady-state methods, since they are able to produce an estimate of the time scale required to meet some water chemistry target given a reduction in acid deposition. These models typically consider annual changes in stream chemistry at one point. However, in order to protect biota from 'acid episodes', quantification of temporal variability needs to encompass event responses; in addition spatial variability across the catchment also needs to be considered. In this paper, modelling of both spatial and temporal variability is combined in a new framework which enables quantification of catchment hydrochemical variability in time and space. Both low and high flow hydro-chemical variability are quantified in terms of statistical distributions of ANC (Acid Neutralisation Capacity). These are then input as stochastic variables to an EMMA (End-Member Mixing Analysis) model which accounts for temporal variability and ANC is hence predicted as a function of time and space across the whole catchment using Monte-Carlo simulation. The method is linked to MAGIC to predict future scenarios and may be used by iteration to calculate critical loads. The model is applied to the headwaters of the River Severn at Plynlimon, Wales, to demonstrate its capabilities. 相似文献