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81.
Microbial catabolic diversity in soils contaminated with hydrocarbons and heavy metals 总被引:1,自引:0,他引:1
Understanding indigenous microbial function in contaminated soil is crucial to the successful development and use of bioremediation technologies. We measured the catabolic diversity of indigenous microbial communities in soils with a 30-yr history of Pb, Cr, and hydrocarbon (HC) contamination using a modified substrate-induced respiration method. There were characteristic differences of microbial respirations in the response of highly versus less contaminated soils to the range of organic substrates used. The catabolic response to glucose as compared to succinic acid was approximately 1:5 in less contaminated soils, but 1:25 in highly contaminated soils. In contrast, the response ratio to glucose versus aromatics was about 1:0.4 in less contaminated soils and 1:1 in highly contaminated soils. Principal components analysis (PCA) of the responses confirmed that catabolic diversity differed between highly and less contaminated soils. Univariate analysis also indicated that catabolic diversity was reduced in highly contaminated soils. This catabolic difference was strongly associated with the alteration of microbial community composition. Statistical analyses suggested that the variation in microbial community catabolic diversity was attributed to HCs more than to Pb and Cr. 相似文献
82.
The advantages associated with the application of a thermochemical data bank system to the investigation of metallurgical and chemical processes are described. In particular, the ready availability of up-to-date, critically evaluated data which may be used in conjunction with specially-written application programs, enables the user to obtain information very rapidly at his own terminal in the tabular or graphical form he requires. The use of such a data bank for carrying out calculations related to certain steel-making problems is demonstrated – namely for guiding deoxidation and desulphurisation operations, for investigating the conditions for formation of precipitated carbide and nitride phases in alloy steels, for determining the effect of alloying elements on hydrogen solubility in iron, and for predicting likely corrosion products in different gaseous environments. 相似文献
83.
Gex-Fabry Marianne Landry Jacques Marceau Normand Gagne Simon 《IEEE transactions on bio-medical engineering》1983,(5):271-277
The development and preliminary verification of a simple two-compartment model describing the thermal response of adjacent normal and cancerous tissues subjected to magnetic induction heating is presented. Analytical expressions were found for estimating the spatial temperature distributions in the system composed of a spherical tumor mass imbedded in a cylindrical normal tissue as a function of the field intensity and the tissue's physical, geometrical, and physiological characteristics. The conditions leading to preferential heating of the tumor are described. 相似文献
84.
The purpose of this study was to evaluate the use of Lactobacillus plantarum, isolated from table olives "Bella di Cerignola," a traditional variety of Apulian region (Southern Italy), as a starter for this kind of food. We focused on the interaction of the starter with the natural occurring microflora, the quantitative/qualitative composition of yeast population, the decrease of pH, and the content of organic acids. After a preliminary characterization, 3 strains of Lb. plantarum, selected for their probiotic and technological performances, were used as a multiple-strain starter and inoculated (approximately 2%) in olives, processed according to Spanish style, brined at 8% and 10% of NaCl and added with 0.5% of glucose. The combination of the starter and glucose assured a correct fermentation course, decreasing the pH up to a safe value (4.3 to 4.5) and controlled the growth of yeasts. The concentrations of both L- and D-lactic acids increased throughout the fermentation, while citric and malic acids (both the isomers D and L) remained at low levels (0.2 to 0.4 g/L). Concerning yeast species, Candida guilliermondii was mainly isolated at the beginning (7 to 14 d), while C. famata prevailed at the end of fermentation. PRACTICAL APPLICATIONS: To the question "How to standardize and maintain quality of "Bella di Cerignola" olives (Southern Italy)" we can suggest the following answer: use Lb. plantarum and a low amount of glucose (0.5%). The result is a decrease of the pH below the safety break point. 相似文献
85.
Conjugated linoleic acid and chromium lower body weight and visceral fat mass in high-fat-diet-fed mice 总被引:1,自引:1,他引:0
More than half of the U.S. population has a body mass index of 25 kg/m2 or more, which classifies them as overweight or obese. Obesity is often associated with comorbidities such as diabetes, cardiovascular
diseases, and cancer. CLA and chromium have emerged as major dietary supplements that reduce body weight and fat mass, and
increase basal metabolic rate in animal models. However, studies show that CLA induces insulin resistance in mice and in humans,
whereas Cr improves insulin sensitivity. Hence, we designed the present study to examine the combined effect of CLA and Cr
on body composition and insulin sensitivity in a Balb/c mice (n=10/group) model of high-fat-diet-induced obesity. CLA alone lowered body weight, total body fat mass, and visceral fat mass,
the last of which decreased further with the combination of CLA and Cr. This effect was accompanied by decreased serum leptin
levels in CLA-fed and CLA+Cr-fed mice, and by higher energy expenditure (EE) and oxygen consumption (OC) in CLA+Cr-fed mice.
Serum levels of glucose, insulin, the pro-inflammatory cytokines, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6),
as well as insulin resistance index (IRI), decreased with CLA, whereas CLA and Cr in combination had significant effects on
insulin and IL-6 concentrations and IRI. In summary, CLA+Cr decreased body weight and fat mass in high-fat-diet-fed mice,
which may be associated with decreased leptin levels and higher EE and OC. 相似文献
86.
Marckmann CJ Andersen CE Aznar MC Bøtter-Jensen L 《Radiation protection dosimetry》2006,120(1-4):28-32
Optical fibre dosemeter systems based on radioluminescence and optically stimulated luminescence (OSL) from carbon-doped aluminium oxide (Al(2)O(3):C) crystals were developed for in vivo real-time dose rate and absorbed dose measurements in radiotherapy and mammography. A technique was also developed for making ultra-small dosemeter probes that can easily be placed inside patients in radiation treatment. These probes have shown excellent properties in both head and neck intensity-modulated radiation therapy treatment and in mammography. The dose-response of the OSL signal for the new optical fibre dosemeter system showed a repeatability within 0.15% at a dose level of 60 mGy when integrated over 100 s. The temperature dependence in the range 0-45 degrees C showed a reproducibility within 1.3% when the OSL signal was integrated over 100 s. 相似文献
87.
In order to investigate a possible relationship between integrin degradation and water-holding capacity (WHC), integrin was quantified using western blot, and water mobility and distribution was measured by proton NMR T(2) relaxometry at 24h postmortem in pork (n=30) with a large variation in WHC (drip loss varying from 2.8% to 11.3%). Regression analyses revealed correlation coefficients of r=-0.32 (P=0.08) and r=0.40 (P=0.03) for the correlations between the content of integrin determined by western blot analysis and WHC determined as either drip loss or by NMR, respectively. Water mobility and distribution was also measured in 18 meat samples upon 7 days of aging, which revealed a correlation (r=0.54) between integrin content determined by western blot analysis 24h postmortem and the mobility of the myofibrillar water (T(21) relaxation time) at day 7. In contrast, no correlation could be established between integrin content 24h postmortem and WHC at day 7 determined by NMR as the amount of extramyofibrillar water (T(22) population) (r=-0.01). In conclusion, both visualisation by CLSM and quantification of integrin by western blot analyses of suggested that a strong link between integrin degradation and WHC in pork is questionable, whereas integrin degradation seems to have impact on the succeeding development in the mobility of the myofibrillar water. 相似文献
88.
Gunnar Suchaneck Vinay S. Vidyarthi Marianne Reibold Alexander Deyneka Lubomir Jastrabik Gerald Gerlach Johannes Hartung 《Journal of Electroceramics》2008,20(1):17-20
Pb(Zr,Ti)O3 (PZT) thin films deposited on insulating ZrO2 buffered silicon wafer are intended to be employed for in-plane polarized piezoelectric MEMS devices. Multi-target reactive
sputtering system for large area deposition of in-situ crystallized PZT thin films and the ZrO2 buffer layer has been employed. The interface analysis of multilayer structures by high resolution transmission microscope,
X-ray diffraction, optical refraction, and absorption spectra studies has been presented. At a substrate temperature of 520°C
and excess lead deposition condition, the formation of a PZT superstructure has been revealed. The substrate temperature of
580°C leads to the crystallization of PZT directly into a single phase perovskite crystal structure. A pronounced Urbach behavior
in our PZT thin films has been observed by optical absorption studies. The surface roughness of PZT films deposited on a ZrO2 buffer layer is much higher than that on conducting platinized silicon wafer. 相似文献
89.
Cover Feature: Nucleoside‐Based Self‐Assembling Drugs for Localized Drug Delivery (ChemMedChem 11/2018)
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90.
Sculfort Ombeline McClure Melanie Nay Bastien Elias Marianne Llaurens Violaine 《Journal of chemical ecology》2021,47(6):577-587
Journal of Chemical Ecology - Chemical defences in animals are both incredibly widespread and highly diverse. Yet despite the important role they play in mediating interactions between predators... 相似文献