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21.
In the Baltic Sea, a large brackish water area, turbot (Scophthalmus maximus) occurs at the border of its distribution with respect to salinity. Using turbot caught in ICES subdivision (SD) 28 (mid-Baltic), salinity requirements for successful egg development were evaluated by assessment of spermatozoa mobility, fertilisation and egg survival at different salinities. Further, to evaluate potential effects of temperatures, egg survival at different temperatures was assessed. Spermatozoa activity and fertilisation rate decreased with decreasing salinity with a significant drop at <7 psu. The viable hatch was significantly lower at <7 psu compared to at 7–15 psu. Hence, due to decreasing salinity this implies lower egg survival in SD 29 and 30 compared to in SD 24–28, and that salinity conditions in SD 31 are insufficient for egg development. Further, following a long period without major inflows of saline water into the Baltic Sea, salinity has decreased. From 1995 onwards salinities <7 psu prevail in SD 27–28 suggesting decreased reproductive success and potentially weaker year-classes in this area. Egg survival was high at 12–18 °C and considerably lower at 9 and 21 °C. Comparing the results with environmental data suggested that spawning time of turbot is adapted to optimum temperatures for egg development, but that occasions with temperatures involving increased egg mortality may occur, e.g. during upwelling situations.  相似文献   
22.
Children's independent access to the outdoors is often restricted by parents, making young children dependent on adult motivation for visits. Since access to play in nature can be beneficial to children's development and health, this study examines the accompanying adults’ motivational factors for bringing their children to playgrounds in urban green spaces. The study used on-site questionnaires to collect data in six public park playgrounds in the U.S. and Denmark, to reveal cultural similarities and differences.The results show that the respondents have different motivations for going to a park playground. The Danish respondents find it most important to be together with their children, while the American respondents find it most important that their children are physically active whilst being there. Other results show that different factors can influence both frequency of visits and length of stays. For Danish respondents, location is very important. Pleasing green surroundings and a nearby location tends to result in more frequent visits. All respondents stay longer and visit more often if they like the social atmosphere of the playground. However, male respondents, who are more active with their children than female respondents, have shorter stays if they dislike the variety of play equipment.Based on the results of this paper, suggestions are made as to how designers, planners and park managers can implement the results into practice, with the aim of increasing adults’ motivation for taking their children to park playgrounds.  相似文献   
23.

Background

Surgical site infection (SSI) is a common nosocomial infection in dogs and a growing concern in veterinary hospitals as an increase in multidrug-resistant pathogens is reported. Despite the need for rational and prudent antimicrobial use, few peer-reviewed and published veterinary studies have investigated the pathogenic growth including susceptibility patterns of the isolated pathogens in canine SSIs.The first objective of the present study was to estimate the distribution of bacterial pathogens in dogs with SSI and to investigate whether this was influenced by type of surgical procedure (clean, clean-contaminated, contaminated or dirty), duration of hospitalization, wound classification and depth of the infection, or antimicrobial treatment. The second objective was to assess susceptibility patterns to clinically relevant antimicrobials.During three years, four animal referral hospitals and three small animal clinics submitted bacterial swabs from canine SSIs for culture and susceptibility, together with a questionnaire completed by the attending clinician.

Results

Approximately two thirds of the in total 194 isolates were staphylococci. Staphylococcus pseudintermedius was the most prevalent finding (46%) followed by beta haemolytic Streptococcus spp. (24%). No associations between distribution of the isolated pathogens and classification of the surgical procedure, duration of hospitalization or depth of the SSI were shown, with the exception of Escherichia coli isolates being significantly more often found in deep wound infections than in superficial skin infections.Overall the possibilities of finding first generations antimicrobials to treat the SSIs included in the study were favorable, as the isolated pathogens were mostly without acquired antimicrobial resistance and multidrug resistance was uncommon. There were only three cases of methicillin-resistant S. pseudintermedius-infections (one percent of all isolates), one case of extended-spectrum beta-lactamase producing E. coli-infection, and no methicillin-resistant Staphylococcus aureus infections.

Conclusions

None of the investigated factors were shown to influence the distribution of bacterial pathogens. The majority of SSIs were caused by staphylococci, and S. pseudintermedius was the most prevalent pathogen. Based on the study results, use of first-line antimicrobials prior to receiving culture and susceptibility results is a rational empirical antimicrobial therapy for the studied dog population.  相似文献   
24.
The metabolites of three species of Apiaceae, also known as Pegaga, were analyzed utilizing (1)H NMR spectroscopy and multivariate data analysis. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) resolved the species, Centella asiatica, Hydrocotyle bonariensis, and Hydrocotyle sibthorpioides, into three clusters. The saponins, asiaticoside and madecassoside, along with chlorogenic acids were the metabolites that contributed most to the separation. Furthermore, the effects of growth-lighting condition to metabolite contents were also investigated. The extracts of C. asiatica grown in full-day light exposure exhibited a stronger radical scavenging activity and contained more triterpenes (asiaticoside and madecassoside), flavonoids, and chlorogenic acids as compared to plants grown in 50% shade. This study established the potential of using a combination of (1)H NMR spectroscopy and multivariate data analyses in differentiating three closely related species and the effects of growth lighting, based on their metabolite contents and identification of the markers contributing to their differences.  相似文献   
25.
26.
A new dimeric carbazole alkaloid, 8,10'-[3,3',11,11'-tetrahydro-9,9'-dihydroxy-3,3',5,8'-tetramethyl-3,3'-bis(4-methyl-3-pentenyl)]bipyrano[3,2-a]carbazole (12), was isolated from the CH(2)Cl(2) extract of Murraya koenigii together with six known carbazole alkaloids, koenimbine (6), O-methylmurrayamine A (7), O-methylmahanine (8), isomahanine (9), bismahanine (10), and bispyrayafoline (11). Their structures were determined on the basis of (1)H and (13)C NMR spectroscopic and mass spectrometric (MS) data. The antioxidative properties of 12 carbazole alkaloids isolated from leaves of M. koenigii were evaluated on the basis of the oil stability index together with their radical scavenging ability against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. On the basis of the lag time to reach a steady state, the 12 carbazoles were classified into three groups. It is suggested that an aryl hydroxyl substituent on the carbazole rings plays a role in stabilizing the thermal oxidation and rate of reaction against DPPH radical.  相似文献   
27.
In boreal forests ericaceous shrubs often dominate the forest floor vegetation. Nitrogen enrichment has been shown to decrease shrub abundance and in this study we explored whether it also affects the root associated fungal communities. Fine roots of Vaccinium myrtillus were collected in a Norway spruce dominated forest and of Vaccinium vitis-idaea in a Scots pine dominated forest. In both forests, nitrogen enrichment was experimentally induced by adding 12.5 and 50 kg N ha−1 yr−1 for 12 (spruce forest) and four (pine forest) years. Based on terminal restriction fragment length polymorphisms, subcloning and sequencing analyses, the root associated fungal communities were examined. We found 93 fungal species including Asco-, Basidio- and Zygo-mycota. In general, the Rhizoscyphus ericae aggregate was the most dominant and this was followed by Herpotrichiellaceae and Sebacina. Ordination analysis revealed that nitrogen enrichment did not change species composition of the fungal communities in neither the spruce nor the pine forest, while fungal community structures were clearly discriminated between the dominant shrub species in each forest. Similarly, no fungal species showed a significant response to nitrogen enrichment. Therefore, nitrogen enrichment appears to have no effect on root associated fungi of understorey dwarf shrubs in boreal forests, while it is clear that spruce and pine forests harbor distinctive communities of these fungi.  相似文献   
28.
The potential of heat and chemically treated rubber wood shavings (RWS) to remove Cu(II) and Ni(II) was evaluated at bench-scale by varying parameters such as initial Cu(II) and Ni(II) concentrations, contact time and adsorbent dosage. Maximum Cu(II) and Ni(II) uptake was achieved using NaOH-treated RWS after 5 h of contact time, pH 5.0 (Cu), 5.5 (Ni) and 6.0 (mixed-metal solution), initial Cu(II) and Ni(II) of 100 mg L?1 and RWS dosage of 0.3% (w/v). Point of zero charge (pHPZC) value of 4.35 suggests the appropriateness of pH range used. Higher Cu(II) and Ni(II) adsorption following NaOH treatment was due to smaller average pore diameter (34.63 Å), higher mesopore content and higher surface negativity charge. EDAX analysis confirmed the presence of Cu and Ni on the surface of the RWS. The importance of carboxyl and hydroxyl functional groups during Cu(II) and Ni(II) removal is supported by the FTIR analysis and good correlation (R 2 of 0.96–0.99) with the pseudo-second-order adsorption kinetic model. The results indicate the potential of using RWS as an alternative adsorbent to remove Cu(II) and Ni(II) from industrial wastewaters.  相似文献   
29.

Blackspot is a serious disease on cultivated roses and resistance is rare; however, some wild Rosa species exhibit a high level of resistance. Disease incidence in field-grown offspring from three seedling families was evaluated as percentage of infected leaves (regardless of the size and number of spots) on each plant. Dolly, Queen Elizabeth and Friesia were used as pistillate parents and the resistant germplasm L83 (derived from the amphidiploid R  相似文献   
30.
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