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321.
Fenbendazole was detected in adult brine shrimp tissue (bioencapsulation) after enrichment periods of 15 minutes, 30 minutes, 1 hour, 2 hours, 4 hours, 8 hours, 12 hours, and 24 hours in baths that contained 2-, 4-, and 8-g/L concentrations of fenbendazole. The assays were performed using high-performance liquid chromatography. A biphasic pattern of peak concentrations at 30 minutes or 1 hour and again at 8 or 12 hours was seen in the shrimp for all treatment concentrations. Percent of fenbendazole available that was incorporated in Artemia approached 100% for all treatment groups. Survival of shrimp was not affected by any of the fenbendazole concentrations, but animal deaths increased with time in all treatment concentrations. It can be concluded that fenbendazole can be successfully bioencapsulated in adult Artemia.  相似文献   
322.
There is no information on the effect of sulfuryl fluoride (SF) on durum wheat technological properties and products made from fumigated durum wheat. Durum wheat and semolina were exposed to a range of SF applications under conditions that might be typically encountered in bulk storage facilities used in many countries. SF greatly reduced the germination percentage of fumigated durum wheat, with increasing impact under higher SF concentration, grain moisture content, and fumigation temperature. SF greatly reduced seed germination percentage, impacting more the higher the SF concentration. SF had little to no effect on grain test weight, 1,000‐grain weight, hardness, protein content, semolina ash content, and mixograph properties. At the highest SF concentration (31.25 mg/L for 48 h) there was a tendency for pasta cooking loss to be increased but still acceptable, and other pasta properties were largely unaffected. Fumigation with SF did not have any impact on the baking properties of a wholemeal durum flour–commercial flour mix. Therefore, SF is not recommended if the grains are to be used as seeds for agricultural production, but for the production of semolina, pasta, and bread, SF used under typical fumigation conditions has little to no impact on technological properties of durum wheat.  相似文献   
323.
CHCl3 and CHBr3 intercalated C60 have attracted particular interest after a superconductivity transition temperature (Tc) of up to 117 K was discovered. We have determined the structure using synchrotron x-ray powder-diffraction and found that the expansion of the lattice mainly takes place in one dimension (triclinic b axis), leaving planes of C60 molecules on an approximately hexagonal, slightly expanded lattice. We have performed tight-binding band structure calculations for the surface layer. In spite of the slight expansion of the layers, for the range of dopings where a large Tc has been observed, the density of states at the Fermi energy is smaller for C60.2CHCl3 and C60.2CHBr3 than for C60. This suggests that the lattice expansion alone cannot explain the increase of Tc.  相似文献   
324.
The biomass and decomposition of coarse woody debris (CWD, ≥10 cm in diameter) were studied in a monsoon evergreen broad-leaved old-growth forest in Dinghushan Nature Reserve, Southern China. The study examined the biomass of CWD from 1992 to 2008 and decomposition of three dominant tree species CWD (Castanopsis chinensis, Cryptocarya concinna, Schima superba) from 1999 to 2008. Changes in the wood density of three tree species’ CWD were used to estimate the decay rates with a single exponential model. The results showed that the biomass of CWD in the old-growth forest was increasing from 17.41 tonnes ha−1 (t ha−1) in 1992 to 38.54 t ha−1 in 2008, and a higher decay constant was observed for C. concinna (0.1570 – 19 years for 95% mass loss); the decay rates of S. superba and C. chinensis were 0.1486 (20 years for 95% mass loss) and 0.1095 (27 years for 95% mass loss), respectively. The difference in decay constant rates may be due to their substrate quality and decomposers. The content of carbon (C) in three species declined after 9 years of decay. Nitrogen (N) content increased in all species with decay. The C/N ratio in the three species declined during the decay process.  相似文献   
325.
Growth and reproduction of triploid and diploid blacklip abalone Haliotis rubra (Leach, 1814) were compared in a 30-month study. Triploidy was induced by inhibition of the second polar body formation using 6-dimethylaminopurine (6-DMAP) or cytochalasin B (CB). There were no significant differences in growth and survivorship between triploid and diploid abalone. However, triploid abalone had a more elongated shell and greater foot muscles than diploid abalone. A slightly curvilinear growth in shell length was conformed to all treatments. While diploid abalone had reached sexual maturity and spawned during the study, gonadal development and gamete maturation were abnormal in triploids. Female triploids lacked an apparent gonad at the macroscopic level but microscopic examination revealed that they had a thin layer of oogonia development. In contrast, male triploids were able to form similar-sized gonads to diploids during most of the reproductive period, but with brown-yellow discolouration and stalled gametogenesis at spermatocyte formation. Sex ratio of triploid abalone did not deviate from 1:1. With the onset of sexual maturation, growth and gonadal maturation occurred concurrently in diploid abalone, and there was no indication that growth of (diploid) abalone was reduced.  相似文献   
326.
Feline coronavirus (FCoV) causes feline infectious peritonitis (FIP). Since 2002, when 20 cats on the Falkland Islands were found to be FCoV seronegative, only seronegative cats could be imported. Between 2005-2007, 95 pet and 10 feral cats tested negative by indirect immunofluorescence antibody (IFA) analysis using two strains of type II FCoV, two transmissible gastroenteritis virus assays, an enzyme-linked immunosorbent assay and rapid immunomigration test. Twenty-four samples (23%) showed non-specific fluorescence, mostly attributable to anti-nuclear antibodies (ANA). The reason for ANA was unclear: reactive samples were negative for Erhlichia canis antibodies; seven were feline immunodeficiency virus positive, but 15 were negative. It was not possible to determine retrospectively whether the cats had autoimmune disease, hyperthyroidism treatment, or recent vaccination which may also cause ANA. The FCoV/ FIP-free status of the Falkland Islands cats should be maintained by FCoV testing incoming cats. However, ANA can complicate interpretation of IFA tests.  相似文献   
327.
Tropical Animal Health and Production - Seventy-two cows were selected for an on-farm study on the effect of feed supplementation before calving on milk production, ovarian activity and calf growth...  相似文献   
328.
329.
OBJECTIVE: This paper provides the rationale for the Guideline Daily Amounts (GDAs) for fat, saturated fat and other nutrients that appear on food labels in the UK. These GDAs are provided voluntarily by manufacturers and retailers and were developed to help people make better use of nutrition labelling--the format of which is prescribed by the European Union's nutrition labelling directive. The paper also describes the basis to some Rules of Thumb for what counts as 'a lot' or 'a little' of fat, saturated fat and other nutrients, in an individual food. DESIGN: The paper gives the background to, and purpose of, the GDAs and Rules of Thumb and explains how they were calculated. It briefly describes their subsequent usage by food producers and others. RESULTS: Both GDAs and the Rules of Thumb first appeared in a leaflet developed by the authors and published in 1996 by the Ministry of Agriculture, Fisheries and Food. GDAs for fat, saturated fat and energy were adopted subsequently by the Institute of Grocery Distribution and then by many retailers and some manufacturers. The Rules of Thumb for fat, saturated fat, sugar and sodium have recently been republished in some leaflets published by the Food Standards Agency in the UK. CONCLUSIONS: GDAs and Rules of Thumb may provide useful ways of helping consumers make sense of nutrition labelling. The current GDAs and the Rules of Thumb could usefully be updated in the light of recent developments.  相似文献   
330.
Immunity-related genes and gene families in Anopheles gambiae   总被引:2,自引:0,他引:2  
We have identified 242 Anopheles gambiae genes from 18 gene families implicated in innate immunity and have detected marked diversification relative to Drosophila melanogaster. Immune-related gene families involved in recognition, signal modulation, and effector systems show a marked deficit of orthologs and excessive gene expansions, possibly reflecting selection pressures from different pathogens encountered in these insects' very different life-styles. In contrast, the multifunctional Toll signal transduction pathway is substantially conserved, presumably because of counterselection for developmental stability. Representative expression profiles confirm that sequence diversification is accompanied by specific responses to different immune challenges. Alternative RNA splicing may also contribute to expansion of the immune repertoire.  相似文献   
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