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排序方式: 共有82条查询结果,搜索用时 15 毫秒
1.
Accelerated tissue expansion with the "overfilling" technique 总被引:3,自引:0,他引:3
J P Pietil? R E Nordstr?m P J Virkkunen P E Voutilainen A E Rintala 《Plastic and reconstructive surgery》1988,81(2):204-207
Temporary overexpansion of the tissues at each filling session increased the actual inflation volume by about 59 percent. This shortened the process of tissue expansion considerably. "Overexpansion" means that the pressure in the expander is increased to a point where the dermal capillary flow is zero or the patient experiences so much discomfort that inflation cannot be carried out any further. The pressure in the expander is thereafter gradually decreased by taking out saline until both the capillary refill and all other clinical criteria are sufficient for safe dermal circulation. Comparison of the expander volume at the final pressure to the initial filling volume at the same pressure before the "overfilling" confirmed an average gain of about 59 percent in 14 patients. 相似文献
2.
Acetate Degradation at 70°C in Upflow Anaerobic Sludge Blanket Reactors and Temperature Response of Granules Grown at 70°C 下载免费PDF全文
Anaerobic acetate degradation at 70°C and at 55°C (as a reference) was studied by running laboratory upflow anaerobic sludge blanket (UASB) reactors inoculated with mesophilic granular sludge. In UASB reactors fed with acetate-containing media (3 g of chemical oxygen demand [COD] per liter, corresponding to 47 mM acetate) approximately 50 days was needed at 70°C and less than 15 days was needed at 55°C to achieve an effluent COD of 500 to 700 mg/liter. In the UASB reactors at both 70 and 55°C up to 90% of the COD was removed. Batch assays showed that sludges from two 70°C UASB reactors, one run at a low effluent acetate concentration and the other run at a high effluent acetate concentration, exhibited slightly different responses to temperatures in the range from 37 to 70°C. Both 70°C sludges, as well as the 55°C sludge, produced methane at temperatures of 37 to 73°C. The 55°C sludge exhibited shorter lag phases than the 70°C sludges and higher specific methane production rates between 37 and 65°C. 相似文献
3.
This study focused on the use of thermophilic anaerobic granulae in the start-up of 70°C acetate-fed upflow anaerobic sludge-blanket (UASB) reactors and the kinetics of granulae grown at 70°C. In the UASB reactors, chemical oxygen demand removal commenced within 48 h of the start-up. The maximum reduction in chemical oxygen demand was 84% with the feed containing yeast and 71% without a yeast supplement. In the bioassays, the yeast-grown sludge converted 98% of the acetate consumed to methane as compared to 92% for the sludge grown without yeast. The highest initial specific methane production rate (µCH
4) of the UASB sludges grown at 70°C was 0.088 h–1 at an acetate concentration of 4.6 mM. The higher initial acetate concentration was found to prolong the lag-phase in methane production significantly and to decrease the µCH
4. The half-saturation constant (K
s), the inhibition constant (K
i), the inhibition response coefficient (n), and the µCH
4
max, calculated according to a modified Haldane equation, were 1.5 mM, 2.8 mM, 0.8, and 0.28 h–1, respectively. The prolonged starvation of the 70°C sludge (15 days) decreased the µCH
4 from about 0.022 h–1 to 0.011 h–1 and increased the lag phase in methane production from 6 h to 24 h as compared to non-starved sludge. 相似文献
4.
Hannu Pöysä Jukka Rintala Aleksi Lehikoinen Risto A. Väisänen 《European Journal of Wildlife Research》2013,59(2):245-256
Populations of migratory species have undergone dramatic changes in recent decades, but little is known about the factors actually driving those changes. Of particular concern are quarry species such as migratory ducks (Anatidae), many of which have an unfavourable conservation status in Europe. By including both quarry and non-quarry species, as well as habitat preference and life history characteristics of the species, we investigated the relative importance of hunting pressure, both in Finland and at the European level, in explaining population changes of 16 species of migratory waterbirds in Finland during 1986–2011. Ban of lead shot in 1996 resulted in considerably lower annual hunting bags in Finland thereafter. Species which had the highest hunting pressure had the most negative slopes in population trends from 1986 up to 1997, suggesting that hunting probably limited those populations. However, in general population trends of the species were not strongly associated with hunting pressure in Finland or in Europe. Nor were basic life history characteristics (body mass and clutch size) associated with population trends of the species. In contrast, recent population declines were associated with habitat preferences of the species: those breeding mainly in eutrophic lakes had more negative population trends than those breeding in oligotrophic lakes or generalist species. Reasons for the relatively poor status of species preferring eutrophic lakes probably include over-eutrophication of nutrient-rich lakes, resulting in less abundant food resources, and increased nest depredation. 相似文献
5.
Environmental variability and population dynamics: do European and North American ducks play by the same rules? 下载免费PDF全文
Hannu Pöysä Jukka Rintala Douglas H. Johnson Esa Lammi Thomas D. Nudds Veli‐Matti Väänänen 《Ecology and evolution》2016,6(19):7004-7014
Density dependence, population regulation, and variability in population size are fundamental population processes, the manifestation and interrelationships of which are affected by environmental variability. However, there are surprisingly few empirical studies that distinguish the effect of environmental variability from the effects of population processes. We took advantage of a unique system, in which populations of the same duck species or close ecological counterparts live in highly variable (north American prairies) and in stable (north European lakes) environments, to distinguish the relative contributions of environmental variability (measured as between‐year fluctuations in wetland numbers) and intraspecific interactions (density dependence) in driving population dynamics. We tested whether populations living in stable environments (in northern Europe) were more strongly governed by density dependence than populations living in variable environments (in North America). We also addressed whether relative population dynamical responses to environmental variability versus density corresponded to differences in life history strategies between dabbling (relatively “fast species” and governed by environmental variability) and diving (relatively “slow species” and governed by density) ducks. As expected, the variance component of population fluctuations caused by changes in breeding environments was greater in North America than in Europe. Contrary to expectations, however, populations in more stable environments were not less variable nor clearly more strongly density dependent than populations in highly variable environments. Also, contrary to expectations, populations of diving ducks were neither more stable nor stronger density dependent than populations of dabbling ducks, and the effect of environmental variability on population dynamics was greater in diving than in dabbling ducks. In general, irrespective of continent and species life history, environmental variability contributed more to variation in species abundances than did density. Our findings underscore the need for more studies on populations of the same species in different environments to verify the generality of current explanations about population dynamics and its association with species life history. 相似文献
6.
Salminen E Rintala J Härkönen J Kuitunen M Högmander H Oikari A 《Bioresource technology》2001,78(1):81-88
Chemical and physical analysis, 27-d plant growth assays with carrot (Daucus carota) and Chinese cabbage (Brassica campestris var. chinensis), and 5-d phytotoxicity assays with Chinese cabbage and perennial ryegrass (Lolium perenne) were used to investigate the suitability of anaerobically digested poultry slaughterhouse waste for fertiliser in agriculture and the effect of aerobic post-treatment on the properties of the digested material. The digested material appeared to be rich in nitrogen. In 27-d assays with digested material as nitrogen source, carrots grew almost as well as those fertilised with a commercial mineral fertiliser used as reference, whereas, the growth of Chinese cabbage was inhibited. In further 5-d phytotoxicity assays, the digested material inhibited the germination and root growth of ryegrass and Chinese cabbage, apparently because of organic acids present in it. Aerobic post-treatment of the material reduced its phytotoxicity but, probably due to the volatilisation of ammonia, resulted in loss of nitrogen. 相似文献
7.
The Aequorea victoria green fluorescent protein (GFP) reporter system is a convenient way to monitor gene expression and other cellular functions in mammalian cells. To study gene expression, a GFP-fusion plasmid construct is often transfected into mammalian cells using a variety of methods including calcium phosphate- and liposome-based DNA transfer. Subsequently, the expression of GFP-fusion protein is monitored by fluorescence microscopy or flow cytometry. Here, we report that certain transfection reagents can produce fluorescence that can be detected in a wide range of wavelengths, which can be confused with GFP-fusion protein. The fluorescence false positives can be a problem, particularly when the GFP expression levels are low. To improve the GFP-based detection or screening methods, it is imperative to include an appropriate negative control and to detect GFP using a narrow-wavelength emission filter corresponding to the emission spectrum around the GFP peak. 相似文献
8.
U. Lignell T. Meklin H. Rintala A. Hyvärinen A. Vepsäläinen J. Pekkanen A. Nevalainen 《Letters in applied microbiology》2008,47(4):303-308
Aims: Microbial concentrations in vacuumed house dust samples (n = 71) were analysed by culture and quantitative polymerase chain reaction (qPCR) methods and their association with extent of moisture damage in the house was studied. Methods and Results: Microbial concentrations measured by qPCR correlated with concentrations obtained by culture method, but were orders of magnitude higher. qPCR also had better sensitivity. Concentrations of several microbes in house dust, determined with qPCR, were associated with the extent of moisture damage in the house. This association was strongest for Penicillium brevicompactum, one of the fungi detected in highest concentrations by qPCR. Furthermore, house dust concentrations of Wallemia sebi, Trichoderma viride, Cladosporium sphaerospermum, Eurotium amstelodami and the combined assay group for Penicillium spp., Aspergillus spp. and Paecilomyces variotii were significantly associated with the extent of the moisture damage. Conclusion: These species or assay groups could probably be used as indicators of moisture damage in the house. Significance and Impact of the Study: This finding indicates the benefits of the qPCR method, which is sensitive enough to reveal the differences in microbial concentrations of house dust between moisture‐damaged and undamaged houses. 相似文献
9.
Municipal grey waste (i.e. the remaining fraction in municipal waste management systems in which putrescibles (biowaste) and other recyclables (paper, metals, glass) are source-segregated) was manually sorted into six main fractions on the basis of composition and also separated by sieving (100 mm mesh size) into two fractions, oversized and undersized, respectively. In practice, in waste management plant the oversized fraction is (or will be) used to produce refuse-derived fuel and the undersized landfilled after biological stabilisation. The methane yields and nitrogen solubilisation of the grey waste and the different fractions (all studied samples were first milled to 5 mm particle samples) were determined in a 237-day methane production batch assay and in a water elution test, respectively. The grey waste was found to contained remnants of putrescibles and also a high amount of other biodegradable waste, including packaging, cartons and cardboard, newsprint, textiles and diapers. These waste fractions comprised 41%-w/w of the grey waste and produced 40-210 m3 methane (total solids (TS))(-1) and less than 0.01 g NH4-N kg TS(added)(-1) except diapers which produced 9.8 g NH4-N kg TS(added)(-1) in the batch assays. In the case of the two sieved fractions and on mass bases, most of the methane originated from the oversized fraction, whereas most of the NH4-N was solublised from the undersized fraction. The first-order kinetic model described rather well the degradation of each grey waste fraction and component, showing the different components to be in the range 0.021-0.058 d(-1), which was around one-sixth of the values reported for the source-segregated putrescible fraction of MSW. 相似文献
10.
Landfast ice algal communities were studied in the strongly riverine-influenced northernmost part of the Baltic Sea, the Bothnian
Bay, during the winter-spring transition of 2004. The under-ice river plume, detected by its low salinity and elevated nutrient
concentrations, was observed only at the station closest to the river mouth. The bottommost ice layer at this station was
formed from the plume water (brine volume 0.71%). This was reflected by the low flagellate-dominated (93%) algal biomass in
the bottom layer, which was one-fifth of the diatom-dominated (74%) surface-layer biomass of 88 μg C l−1. Our results indicate that habitable space plays a controlling role for ice algae in the Bothnian Bay fast ice. Similarly
to the water column in the Bothnian Bay, average dissolved inorganic N:P-ratios in the ice were high, varying between 12 and
265. The integrated chlorophyll a (0.1–2.2 mg m−2) and algal biomass in the ice (1–31 mg C m−2) correlated significantly (Spearman ρ = 0.79), with the highest values being measured close to the river mouth in March and during the melt season in April. Flagellates
<20 μm generally dominated in both the ice and water columns in February–March. In April the main ice-algal biomass was composed
of Melosira arctica and unidentified pennate diatoms, while in the water column Achnanthes taeniata, Scrippsiella hangoei and flagellates dominated. The photosynthetic efficiency (0.003–0.013 (μg C [μg chl a
−1] h−1)(μE m−2s−1)−1) and maximum capacity (0.18–1.11 μg C [μg chl a
−1] h−1) could not always be linked to the algal composition, but in the case of a clear diatom dominance, pennate species showed
to be more dark-adapted than centric diatoms. 相似文献