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991.
Mustafa A Andersson R HellEnäs KE Aman P Kamal-Eldin A 《Journal of agricultural and food chemistry》2008,56(23):11234-11237
The effect of storage conditions on the residual acrylamide content of unfermented rye crispbread was studied in a model system. When milled samples were stored at -80 to 6 degreesC for up to 224 days in double sealed plastic bags, no change in acrylamide content was observed. However, when the milled samples were stored under warmer conditions (20 and 40 degreesC), a notable reduction in acrylamide was noted (22% and 29%, respectively). When stored at 40 degreesC for 70 days in glass tubes, acrylamide content in the samples decreased by 37% in the capped samples, while the decrease in the uncapped samples was in the order of 15%. Finally, a notable reduction of 80% was found when samples were stored at increased moisture level at 40 degreesC for 70 days in capped glass containers. These results highlight that moisture content seems to be of importance for reduction of acrylamide content during storage of food and analytical samples. 相似文献
992.
- 1. Fish assemblages of shallow‐lagoonal biotopes (seagrass beds, coral patches, reef flat and sand) were examined within the Nabq Managed Resource Protected Area (MRPA), South Sinai, Egypt. This protected area supports a small‐scale artisanal Bedouin fishery, managed by gear restrictions and a network of no‐take zones (NTZs).
- 2. Coral patches showed highest species richness and diversity of fish, followed in order by the reef flat, shallow seagrass beds and sandy bottoms.
- 3. There were clear differences in fish assemblages between the biotopes surveyed, little differences between sampling areas and no significant differences in fish assemblages between no‐take and take zones, suggesting species characteristic of these shallow‐water biotopes are dispersed along the coast irrespective of fishing pressure.
- 4. Nine species (Acanthurus nigrofuscus, Asterropteryx semipunctatus, Cryptocentrus caeruleopunctatus, Cheilio inermis, Thalassoma rueppellii, Lethrinus mahsena, Lethrinus nebulosus, Parupeneus forsskali and Pomacentrus trilineatus) had a 95% correlation to the pattern of assemblage distribution, indicating these species are the most important determinants of the fish community.
- 5. Approximately one‐third of fishes recorded appeared to be juveniles, with seagrass beds having a particularly high proportion of juvenile fish, including several commercial species.
- 6. The structure of the fish assemblage and fish size suggests that shallow‐water biotopes in Nabq MRPA may be acting as nursery areas of commercial fish for the Bedouin fishery.
993.
Divers TJ Cummings JE de Lahunta A Hintz HF Mohammed HO 《American journal of veterinary research》2006,67(1):120-126
OBJECTIVE: To determine whether equine motor neuron disease (EMND) could be induced in adult horses fed a diet low in vitamin E and high in copper and iron. ANIMALS: 59 healthy adult horses. PROCEDURE: Horses in the experimental group (n = 8) were confined to a dirt lot and fed a concentrate low in vitamin E and high in iron and copper in addition to free-choice grass hay that had been stored for 1 year. Control horses (n = 51) were fed a concentrate containing National Research Council-recommended amounts of copper, iron, and vitamin E. The hay fed to control horses was the same as that fed to experimental horses, but it had not been subjected to prolonged storage. Control horses had seasonal access to pasture, whereas experimental horses had no access to pasture. Horses that developed clinical signs of EMND were euthanatized along with an age-matched control horse to determine differences in hepatic concentrations of vitamin E, vitamin A, copper, iron, and selenium. RESULTS: 4 experimental horses developed clinical signs of EMND. Plasma concentrations of vitamin E decreased in all 8 experimental horses. There were no significant changes in plasma concentrations of vitamin A, selenium, and copper or serum concentrations of ferritin. There were no significant differences in those analytes between experimental horses with EMND and experimental horses that did not develop EMND. No control horses developed EMND. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that lack of access to pasture, dietary deficiency of vitamin E, or excessive dietary copper are likely risk factors for EMND. 相似文献
994.
Huang W Ma K Zhang J Qatanani M Cuvillier J Liu J Dong B Huang X Moore DD 《Science (New York, N.Y.)》2006,312(5771):233-236
Liver mass depends on one or more unidentified humoral signals that drive regeneration when liver functional capacity is diminished. Bile acids are important liver products, and their levels are tightly regulated. Here, we identify a role for nuclear receptor-dependent bile acid signaling in normal liver regeneration. Elevated bile acid levels accelerate regeneration, and decreased levels inhibit liver regrowth, as does the absence of the primary nuclear bile acid receptor FXR. We propose that FXR activation by increased bile acid flux is a signal of decreased functional capacity of the liver. FXR, and possibly other nuclear receptors, may promote homeostasis not only by regulating expression of appropriate metabolic target genes but also by driving homeotrophic liver growth. 相似文献
995.
Riad H Khalil Amany M Diab Medhat S Shakweer Hanan A Ghetas Mohammed M Khallaf Amira AE‐D Omar 《Aquaculture Research》2018,49(7):2357-2365
This work was carried out to investigate the effects of injection of Tenacibaculum maritimum formalin‐killed cells (FKC), extracellular products (ECPs) and crude lipopolysaccharide (LPS) as well as 1% feed supplements of oil extracts of Echinacea purpurea and Origanum vulgare on sea bass immunity improvement to the favour of T. maritimum experimental infection control after 4 weeks of the experiment. Tenacibaculum maritimum isolated from naturally infected sea bass showed brown to yellowish‐brown lesions (sores) on gills, skin and/or fins and identified by different biochemical methods and polymerase chain reaction technique. Immune parameters namely, total protein, globulin and lysozyme activity, as well as the relative level of protection were improved by T. maritimum (FKC), (LPS), (ECPs), O. vulgare and E. purpurea, respectively compared with control. Histopathological examination of T. maritimum naturally infected sea bass indicated many pathological changes in gill, skin and musculatures. Present study could be concluded that application of T. maritimum (FKC), (LPS), (ECPs), O. vulgare or E. purpurea improved sea bass immunity to the favour of disease resistance against T. maritimum. Further investigations on the combination between the previous control methods and the vaccine application methods will be needed. 相似文献
996.
Abu Hena Mustafa Kamal Omar Hishamuddin Claude E. Boyd 《Journal Of Applied Aquaculture》2018,30(1):47-62
Soil physicochemical properties of the growout ponds of black tiger shrimp (Penaeus monodon) were examined in relation to shrimp yields for one production cycle. The culture ponds were old (>5 years) and new (newly constructed) types. Soil texture was silty clay with low sand content and high proportion of clay for both the pond types with alkaline soil pH (7.87–9.71). Organic matter (OM) concentration was higher (7.48 ± 0.01%) in old ponds and positively related (r = 0.58, P < 0.05) with total nitrogen (TN). The major cations (Ca, Mg, and Na) were higher in the soil of old ponds and did not fluctuate significantly during culture. The majority of trace elements, i.e., Fe (349.22 ± 35.7 ppm), Mn (56.19 ± 30.2 ppm), Zn (88.56 ± 8.09 ppm), Al (454.3 ± 200.6), Pb (1.3 ± 0.96 ppm), Co (3.4 ± 0.2), V (6.56 ± 1.79 ppm), Cr (19.32 ± 0.63 ppm), Ti (82.78 ± 54.3 ppm), As (5.60 ± 0.28 ppm), Ag (0.38 ± 0.5 ppm), and Sb (3.89 ± 0.48 ppm) were found to be higher in new pond soils than the old ponds. Except for soil manganese, no major fluctuations in trace elements were observed during the culture period. Shrimp growth was not significantly different in the two types of ponds, and no distinct correlation between shrimp growth and element content of soils could be drawn. The results indicate that shrimp pond age may not affect production of shrimp if soils are properly managed pre- and postculture. The differences in production in different ponds might be the result of management practice such as quality of shrimp post larvae, pond preparation, water and feed quality, and available live feed in the pond bottom or other environmental factors like water nutrients and physicochemical parameters. 相似文献
997.
Pathotypes and phylogenetic variation determine downy mildew epidemics in Brassica spp. in Australia
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Isolates of Hyaloperonospora brassicae inoculated onto cotyledons of 28 diverse Brassicaceae genotypes, 13 from Brassica napus, two from B. juncea, five from B. oleracea, two from Eruca vesicaria, and one each from B. nigra, B. carinata, B. rapa, Crambe abyssinica, Raphanus sativus and R. raphanistrum, showed significant effects (P ≤ 0.001) of isolate, host and their interaction. Host responses ranged from no visible symptom or a hypersensitive response, to systemic spread and abundant pathogen sporulation. Isolates were generally most virulent on their host of origin. Using an octal classification, six host genotypes were identified as suitable host differentials to characterize pathotypes of H. brassicae and distinguished eight distinct pathotypes. There were fewer, but more virulent, pathotypes in 2015–2016 isolates than 2006–2008 pathogen populations, probably explaining the increase in severity of canola downy mildew over the past decade. Phylogenetic relationships determined across 20 H. brassicae isolates collected in 2006–2008 and 88 isolates collected in 2015–2016 showed seven distinct clades, with 70% of 2006–2008 isolates distributed within clade I (bootstrap value (BVs) of 100%) and the remaining 30% in clade V (BVs 83.3%). This is the first study to define phylogenetic relationships of H. brassicae isolates in Australia, setting a benchmark for understanding current and future genetic shifts within pathogen populations; it is also the first to use octal classification to characterize pathotypes of H. brassicae, providing a novel basis for standardizing phenotypic characterization and monitoring of pathotypes on B. napus and some crucifer species in Australia. 相似文献
998.
999.
Riyazaddin Mohammed Ashok Kumar Are Rajendra S. Munghate Anil Gaddameedi Kavi Kishor Polavarapu Bilhan Hari C. Sharma 《Euphytica》2018,214(2):32
Sorghum shoot fly, Atherigona soccata is an important pest of sorghum during the seedling stage, which influences both fodder and grain yield. To understand the nature of inheritance of shoot fly resistance in sorghum, we performed generation mean analysis using two crosses IS 18551 × Swarna and M 35-1 × ICSV 700 during the 2013–2014 cropping seasons. The F1, F2, BC1 and BC2 progenies, along with the parental lines were evaluated for agronomic and morphological traits associated with resistance/susceptibility to sorghum shoot fly, A. soccata. The cross IS 18551 × Swarna exhibited significant differences between the parents for shoot fly deadhearts (%) in the postrainy season. The progenies of this cross exhibited lower shoot fly damage, suggesting that at least one of the parents should have genes for resistance to develop shoot fly-resistant hybrids. Leaf glossiness, leafsheath pigmentation and plant vigor score during the seedling stage exhibited non-allelic gene interactions with dominant gene action, whereas 100 seed weight showed both additive and dominant gene interactions. Presence of awns showed recessive nature of the awned gene. Generation mean analysis suggested that both additive and dominance gene effects were important for most of the traits evaluated in this study, but dominance had a more pronounced effect. 相似文献
1000.
Yan-xiu WANG Ya HU Bai-hong CHEN Yan-fang ZHU Mohammed Mujitaba Dawuda Sofkova Svetla 《农业科学学报》2018,17(4):857-866
A study was conducted in attempting to identify the cold-resistant apple rootstocks and to establish a comprehensive evaluation system. In this study, 10 elite apple dwarfing rootstocks(GM256, JM7, M26, M7, SC1, SH1, SH38, SH6, M9, and T337) were employed for the experiment and the following parameters were investigated under different low temperature stress conditions(0, –15, –20, –25, –30, and –35°C): the changes of the relative electrical conductivity(REC), anthocyanin content, protein content, soluble sugar content, soluble starch content, proline content, malondialdehyde(MDA) content, superoxide dismutase(SOD) activity, and peroxidase(POD) activity of the dormant branches. The inflection temperature that could represent the plant tissue semi-lethal temperature(LT_(50)) was obtained by the measurements of REC. The LT_(50) was used to evaluate eight other indices. The results showed that there was no significant correlation between LT_(50) and POD activity as well as between the soluble sugar, protein and proline contents at 0 and –15°C. Soluble starch content at 0 and –15°C and anthocyanin content at –15–(–30)°C were significantly but negatively correlated to the LT50 and the MDA content at 0–(–20)°C was significantly positively correlated to the LT_(50). Statistical analysis based on principal component analysis and LT50 showed that cold resistant apple rootstocks in the decreasing order from high to low as GM256, SH6, SH38, SH1, SC1, M26, M7, JM7, T337, and M9. 相似文献