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21.
The behavior of 2 spectacled bears (Tremarctos ornatus) was studied at Wroclaw Zoo (Poland), where they were housed in a very small outdoor enclosure, and then in a separate study after transfer to a large naturalistic exhibit at Chester Zoo (CZ; United Kingdom). The studies combine to form an opportunistic “experiment” on the effects of transfer on zoo animals. This situation provided a unique opportunity for a closer investigation of known behavior problems and their causation. In part 1 of the study, at Wroclaw Zoo, the median amount of time devoted to stereotypical movements was 57 min/h. After the move to CZ, immediate changes in behavior were reported in 1 individual, for whom the stereotypy was eradicated. The other bear continued performing repetitive behavior of high intensity and only used a small area of the large enclosure. Signs of dental problems were subsequently observed in both bears, and so a dental examination was carried out, resulting in multiple extractions. After treatment, the amount of time that the bear with ongoing behavior problems spent stereotyping reduced significantly, and foraging increased. Our data suggest the bears' stereotypic behavior occurred not only in response to an understimulating environment in their old enclosure but also perhaps in association with medical conditions in one of the bears. Although other factors could have contributed to the observed reduction in stereotypy, it is clear that further investigation is needed into the effects of pain and physical condition on stereotypy in animals.  相似文献   
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Chemical analyses and mass spectrometry were used to study the structure of the lipopolysaccharide (LPS) isolated from Aeromonas bestiarum strain K296, serotype O18. ESI-MS revealed that the most abundant A. bestiarum LPS glycoforms have a hexa-acylated or tetra-acylated lipid A with conserved architecture of the backbone, consisting of a 1,4′-bisphosphorylated β-(1→6)-linked d-GlcN disaccharide with an AraN residue as a non-stoichiometric substituent and a core oligosaccharide composed of Kdo1Hep6Hex1HexN1P1. 1D and 2D NMR spectroscopy revealed that the O-specific polysaccharide (OPS) of A. bestiarum K296 consists of a branched tetrasaccharide repeating unit containing two 6-deoxy-l-talose (6dTalp), one Manp and one GalpNAc residues; thus, it is similar to that of the OPS of A. hydrophila AH-3 (serotype O34) in both the sugar composition and the glycosylation pattern. Moreover, 3-substituted 6dTalp was 2-O-acetylated and additional O-acetyl groups were identified at O-2 and O-4 (or O-3) positions of the terminal 6dTalp. Western blots with polyclonal rabbit sera showed that serotypes O18 and O34 share some epitopes in the LPS. The very weak reaction of the anti-O34 serum with the O-deacylated LPS of A. bestiarum K296 might have been due to the different O-acetylation pattern of the terminal 6dTalp. The latter suggestion was further confirmed by NMR.  相似文献   
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Journal of Soils and Sediments - The objective of this study was to evaluate the mutual relations between the soil organic matter (SOM) fractions: fulvic acids (FA), humic acids (HA), humins (HN),...  相似文献   
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Plant Foods for Human Nutrition - This study analysed fruits of cranberry cultivars: Ben Lear, Bergman, Early Richard, Pilgrim and Stevens and compared them with wild-grown cranberry fruits. The...  相似文献   
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Nanomaterials and particularly silver nanoparticles (AgNPs) have increased great interest in many fields of science. The element may affect plant growth and development but so far research studies have been scarce and their results disparate. Tulip is one of the most important ornamental plants and its production technology is constantly being improved. The aim of this study was to investigate the effects of AgNPs on growth and yield attributes of tulip cv. ‘Pink Impression’. Before planting, the tulip ‘Pink Impression’ bulbs were soaked in the following concentrations of AgNPs: 25, 50, 100 and 150?mg?L-1. Control bulbs were soaked in deionized water. The plants were forced in a greenhouse for two growing seasons. The tulips treated with 100?mg?L?1 AgNPs flowered earlier, had longer cut-flower stem, larger petals, greater stem diameter and cut-flower fresh weight. Moreover, at this concentration of AgNPs, they showed increased leaf greenness index (SPAD), stomatal conductance, root fresh weight, root length and produced daughter bulbs of the greatest weight. The study outcomes indicate that AgNPs may be used as plant growth promoters in horticulture.  相似文献   
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The study was conducted in the years from 2011 to 2013 at the Research Institute of Horticulture in Skierniewice, Poland. The aim of the research was to assess the breeding value, based on the effects of general and specific combining abilities (GCA and SCA), of 15 parental genotypes of blackcurrant in terms of fruit yield and quality. The plant material consisted of F1 generation seedlings obtained by crossing, in a factorial mating design of twelve maternal (‘Bona’, ‘Big Ben’, ‘Chereshnieva’, Kupoliniai’, ‘Gofert’, ‘Tines’, ‘Sofievskaia’, ‘Tihope’, ‘Ores’, ‘Ruben’, ‘Titania’ and D13B/11) and three paternal cultivars (‘Ceres’, ‘Foxendown’ and ‘Saniuta’). It was found that the cultivars ‘Ruben’, ‘Big Ben’, ‘Gofert’ and D13B/11 had significant positive effects of GCA on fruit yield at least in two consecutive years. ‘Ruben’, ‘Saniuta’ and D13B/11 had positive GCA effects on fruit weight. For ‘Chereshnieva’, ‘Gofert’, ‘Tines’, ‘Sofievskaia’, ‘Tihope’, ‘Titania’, ‘Ceres’ and Saniuta’ positive GCA effects were estimated for soluble solids content, whereas ‘Ruben’, ‘Ceres’, ‘Gofert’ and ‘Ores’ had positive GCA effects on the ascorbic acid content in fruit. This indicated a high breeding value of these parental genotypes in terms of the evaluated traits. The significantly positive values of SCA, estimated for the crossing combinations: ‘Big Ben’?×?‘Saniuta’, ‘Ruben’?×?‘Foxendown’, ‘Titania’?×?‘Ceres’, ‘Kupoliniai’?×?‘Saniuta’, ‘Gofert’?×?‘Foxendown’, ‘Gofert’?×?‘Saniuta’, ‘Tines’?×?‘Ceres’ and ‘Tihope’?×?‘Foxendown’ for at least two traits describing fruit yield and quality, were evidence of the interaction of both these parental genotypes in the creation of new dessert-type cultivars of blackcurrant.  相似文献   
27.
The study compares lyophilized broccoli sprouts and florets in terms of their chemical composition, cytotoxic and proapoptotic potential against hepatocellular carcinoma HepG2, colorectal cancer SW480, and skin fibroblast BJ cells. Sinapic and isochlorogenic acids were predominant phenolics in the sprouts and florets, respectively. The amount of sulforaphane in the sprouts was significantly higher vs. florets. Oleic and linoleic acids dominated in the sprouts, while caproic, stearic and oleic acids in the florets. Broccoli sprouts were selectively cytotoxic on HepG2 and SW480 cells, with proapoptotic effect for the latter, while the florets were less selective, but more active, with profound proapoptotic effect for HepG2 cells (77.4%). Thus, lyophilized broccoli sprouts may be effectively used in dietary chemoprevention.  相似文献   
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The aim of this study was to find the biochemical markers of blackleg, evoked by the fungus Leptosphaeria maculans in seedlings of oilseed winter rape. Analyses of antioxidant enzymes activity and reactive oxygen species detection were performed 24, 48 and 72 h after inoculation. Moreover, measurements of the total pool of phenolic compounds, trans-cinnamic acid and ferulic acid were carried out. The results proved the virulence of Ph L5 isolate towards the rape seedlings. An increase in total phenolic content, including trans-cinnamic acid, was observed 24 h after inoculation. High activity of phenylalanine ammonia-lyase is probably another symptom of the defense mechanisms, despite the fact that it was not accompanied by elevated phenolics level, which were probably rapidly exhausted during Phoma lingam inoculation. A drop in phenolics content was balanced by higher activity of SOD, CAT and non-specific peroxidases. Enhanced activity of these enzymes was a response to the reactive oxygen species overproduction. ROS accumulation in indirectly inoculated first true leaves after inoculation may suggest a systemic defense response.  相似文献   
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