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1.
There is no report of diversity, biological properties and bioactive compounds of sponge-associated fungi from Indonesia’s mangrove ecosystem to date. This study was designed to isolate sponge-associated fungi from a mangrove ecosystem in Mangkang, to screen the antimicrobial and extracellular enzyme properties of the isolates, characterize the biologically promising isolates using molecular approaches, and profile the secondary metabolites using phytochemical and thin-layer chromatography (TLC) analyses. An unidentified sponge that lived in association with mangrove roots was collected from Mangkang. Total of eight associated fungi were isolated from the sponge. Among all isolates, only two fungi SPMKF 1 and SPMKF 6 produced extracellular amylase, another two fungi SPMKF 4 and 5 showed antibacterial activity against MRSA, and only one fungus SPMKF 8 was able to produce extracellular amylase and show antimicrobial activity against ESBL E. coli, Salmonella enterica ser. Typhi strain MDR and C. albicans, while SPMKF 2, SPMKF 3 and SPMKF 9 did not show any biological properties. The result of genetic characterization proved that SPMKF 1 was Cladosporium tenuissimum, SPMKF 4 was Eutypella sp., SPMKF 5 was Lasiodiplodia theobromae, SPMKF 6 was Fusarium keratoplasticum and SPMKF 8 was F. solani. Furthermore, an amylase gene was detected in fungi SPMKF 1, 6 and 8 while among the BGC, only NRPS genes were detected in SPMKF 4, 5 and 8. Interestingly, several same metabolites indicating the same retention factor (Rf) values in TLC were detected in the fungal crude extracts by TLC.  相似文献   
2.
Survival and vitality of Gremmeniella abietina on Pinus sylvestris slash was studied in northern Sweden during 2003 and 2004. Once a month between September 2003 and April 2004, two to three trees were cut down and debranched. Shoots with pycnidia were sampled at the felling date and then at every consecutive month. The percentage of germinated conidia from each shoot was calculated after 24, 48 and 72 h incubation. The vitality of G. abietina pycnidia in the slash remained high the whole period. Intact pycnidia were found on slash several months after the time of conidial sporulation, which indicates that new pycnidia may be produced on dead pine branches. Sampling of shoots from slash on 13‐ to 18‐month‐old clear‐cuts showed conidial germination capacity as high as in pycnidia collected in fresh slash. Due to survival of G. abietina in slash it is recommended to postpone planting of P. sylvestris seedlings in northern boreal areas to the third vegetation period after sanitary clear‐cuts.  相似文献   
3.
The course of events from taking a food into the mouth to the perception of the food's flavor involves many steps, from dilution with saliva, mastication, and transportation of the compounds to the olfactory epithelium to transformation into signals that go to the brain. In addition, there are also the effects of the food's structure and properties. In this study, a proton-transfer-reaction mass spectrometer (PTR-MS) was used to investigate how four pectin-containing systems with different structures and strengths affected the release of aroma compounds in a model mouth and in the nose of an assessor. Both the model mouth and the in-nose measurements showed that the strength and structure of pectin-containing systems are important with regard to the quantity of aroma compounds that are released. Mastication and saliva were also shown to have a large influence on how much of the aroma compound is released from the mouth to the nose.  相似文献   
4.
It is possible to rapidly detect the presence of high concentrations of sediment associated hydrocarbons using a sediment profile camera and simultaneously evaluate the general sedimentological and biological character of a contaminated area. In sediments that were heavily contaminated with hydrocarbons from spills and chronic long-term additions the presence of hydrocarbons was seen about 50% of the time in the sediment profile images as unique features, ‘H spots’. The presence of these features was related to the concentration of hydrocarbons in the sediment. In highly contaminated muddy sediments ‘H spots’ were found in images collected at stations that had from 270 to 610 ppt total hydrocarbons. Sedimentological and biological information obtained from the sediment profile images confirmed the impacted nature of Elizabeth River sediments. Sediment profile imaging provide a means of obtaining an overall evaluation of the quality of a habitat and impacts on that habitat from pollution related environmental disturbances. While qualitative, an advantage of sediment profile image data is that they can be evaluated in less than a day and used to quickly locate inclusions of hydrocarbons in the sediments for further quantitative chemical or biological sampling, or mapping of heavily contaminated areas.  相似文献   
5.
Due to the great year-round demand for forest products, off-road forestry traffic occurs even when the ground is susceptible to soil compaction and rutting. We investigated the impacts of repeated passes with a laden forwarder (34?Mg) on the soil physical properties of two clear-cuts on stony till soils in northern Sweden. Core samples (n?=?71) were collected from the top 5?cm of mineral soil in and beside wheel tracks, after six passes with the forwarder. Soil physical properties were quantified using classical soil physical analyses and X-ray tomography. The hydraulic conductivity was 70% lower in the wheel tracks than in the soil beside. The X-ray image analysis indicated that this was due to the smaller total volume and lower connectivity of structural pores (φ?>?60?µm). Total porosity was 24% and 12% lower in the tracks at the two sites respectively, and mean bulk density was 1.39?g?cm?3 in the tracks, compared to 1.13?g?cm?3 beside them. To conclude, traffic changed the soil physical properties in a way that may lead to longer periods of high water content in the wheel tracks, increased risk of surface runoff and insufficient aeration for optimal seedling growth.  相似文献   
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7.
Six hunting dogs were investigated after showing signs of diffuse back pain. In three of the dogs, prodromal signs included coughing. Swelling in the dorsal lumbar region was noted in four of the dogs, but in two there was no visible or palpable swelling. Initial radiographs of the lumbar region were normal in two of the dogs and showed mild to moderate ventral periosteal reactions in the L1 to L4 region in the remaining four. On ultrasonography and magnetic resonance imaging, changes were seen in the sublumbar muscles (e.g., abnormal echogenicity and increased signal intensity) in five dogs examined. Exploratory surgery revealed plant material foreign bodies in the sublumbar muscles in the L1 to L4 region in five of the six dogs. The concurrent infections were caused predominantly by anaerobic bacteria common to the mucous membranes of the oropharyngeal and respiratory tracts. All dogs recovered, with restored hunting ability. The mean follow-up period was five years (range 1.3 to 7.8 years). It is proposed that the plant parts were inhaled, and then migrated along either diaphragmatic crus to lodge in the sublumbar muscles.  相似文献   
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9.
The prevalence of chronic valvular disease was studied in 494 cavalier King Charles spaniels with a mean (+/- sd) age of 3.0 +/- 2.7 years. Cardiac murmurs were detected in 65 (13.2 per cent) of the dogs. Among 61 cavalier King Charles spaniels with a mean age of 6.4 +/- 2.8 years, cardiac murmurs were detected in 32 (52 per cent). In both groups of dogs the prevalence of cardiac murmurs was low among dogs younger than three years (1.9 per cent) but increased with age (P < 0.001). The estimated ages at which 50 per cent of the dogs had developed murmurs were 7.5 and 6.2 years, respectively. When 39 of the 61 dogs were re-examined three years later, cardiac murmurs were detected in 28 (72 per cent), and the intensities of the murmurs had generally increased (P < 0.05). Nine (28 per cent) of the dogs which had previously had murmurs had been euthanased for signs of congestive heart failure whereas none of the dogs which had been free of murmurs had died from congestive heart failure. Animal insurance statistics from 1982 to 1990 (1983 excluded) for dogs less than 10 years old showed that claims for veterinary care or death or euthanasia were five times more common in the cavalier King Charles spaniel than in dachshunds (P < 0.001) and eight times more common than the mean for all other insured breeds (P < 0.001).  相似文献   
10.
Clearcutting is the main method of harvesting boreal forests, to some extent mimicking natural disturbances by fire and wind-felling. Effects of clearcutting on vertebrate fauna in managed forests was examined by small mammal trapping in spring and autumn, winter censuses of mammal snow tracks and censuses of birds in spring and summer in one central and one edge (125 m) section of large clearcuts and mature forests, respectively. There was a separate clearcut fauna, at least on large clearcuts, that was well distinguished from the forest fauna. There was not any physiognomic ecotone but the forest fauna showed a marked edge effect with larger numbers of many species in the peripheral parts of the forest. In the forests examined, with a Western European bird fauna, there were no typical interior forest species, in contrast to northern taiga forests. The present forest species easily changed distributions seasonally and according to variations in snow conditions and food abundance. Such generalist species in the boreal forest will therefore vary considerably in local density according to landscape composition but will also show large-scale persistence. They may have been selected for as a result of man's restructuring of temperate and boreal landscapes, e.g. by forest management. Edge effects seem to arise for several reasons but will probably only apply to generalist species.  相似文献   
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