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21.
The fundamental step in the identification of the most appropriate strategy for the remediation of sites contaminated with dense nonaqueous phase liquids (DNAPLs) is a comprehensive characterization of the contaminated source region as the morphology of DNAPL strongly governs the mass transfer processes. The influence of DNAPL distribution geometry and groundwater flow velocity on mass reduction was explored through the evaluation of a series of laboratory studies conducted in a two-dimensional tank under different hydrodynamic conditions. An image analysis procedure was used to determine the distribution of DNAPL saturation and the morphology of the contaminated region. Experimental observations revealed a dependence of mass transfer rate on the aqueous phase velocity under high flow regimes, whereas the mass transfer rate was controlled mainly by morphometric indexes under low velocity flow conditions. Experimental results indicate that higher mass reduction and contaminant fluxes are obtained at low saturation values. The mass flux emanating from an elongated source aligned perpendicularly to the direction of water flow is greater due to a higher DNAPL?Cwater contact surface in comparison to a lower mass flux from horizontal pools with high saturation. These aspects should be considered in an inverse modeling technique for locating the source zone and also in all remediation approaches based on an increase in water circulation through a contaminated zone (i.e., pump and treat).  相似文献   
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Anthocyanins (Anths) in olive (Olea europaea L.) fruits at different degrees of pigmentation were assessed nondestructively by measuring chlorophyll fluorescence (ChlF). The method is based on the comparison of the ChlF excitation spectra from olives with different pigmentation from green to green-red, reddish-purple, and purple. The logarithm of the ratio between the fluorescence excitation spectra (logFER) from two different colored zones gave the difference in the absorption spectrum between them. The absorbance spectrum derived from the logFER between a red olive and the same olive devoid of the skin showed the typical Anth green band (at 550 nm). It matched that recorded by microspectrophotometry on a single pulp cell and the in vitro absorbance spectrum of the olive skin extract. As expected, the in vivo Anths absorption maximum increased in intensity going from less to more mature olives and was higher in the sun-exposed olive side with respect to the sun-shaded side. Absolute quantitative nondestructive determination of Anths for each olive sample was obtained by the logFER calculated for two excitation wavelengths, 550 and 625 nm, of ChlF at 740 nm. Going from green to purple skin colors, the Log[ChlF(625)/ChlF(550)] was fairly well-correlated to the extract Anths concentration. Finally, the relationship between the Anths and the other main phenolics present in the olives analyzed by high-performance liquid chromatography was evaluated. The main result was a net increase of verbascoside with increasing Anths content. On the basis of our results, the development of a new rapid and noninvasive method for the monitoring of olive development and ripening can be envisaged.  相似文献   
23.
CD154 is a cell surface molecule expressed by activated T cells. CD40 and CD154 interaction is critically important in regulating humoral and cell-mediated immune responses. In this study we have investigated whether a DNA vaccine encoding rhoptry protein 1 (ROP1) of Toxoplasma gondii, and encoding ovine CD154 induces an enhanced ROP1-specific immune response in sheep. Two groups of twelve animals received two intramuscular injections, of a DNA plasmid encoding T. gondii ROP1 antigen (group 1) or an ROP1 antigen fused to ovine CD154 (group 2). There were two control groups of sheep. One was injected with an empty vector (group 3) and the other received no injections at all (group 4). The injection of the plasmid containing ROP1 (group 1) at weeks 0 and 4 induced a significant IgG2 response at week 2 which was amplified at week 4 after the booster injection and persisted to week 8 compared to the control animals in groups 3 and 4. For IgG1, significant differences from the control animals were only observed from week 5 onwards. The fusion of CD154 and ROP1 elicited significant IgG1 and IgG2 responses from week 1 which were amplified from weeks 5 to 8 compared to the control animals in groups 3 and 4. The IgG1 response was significantly higher in group 2 animals receiving pROP1-CD154 compared to group 1 receiving pROP1 only. There was no significant difference in IgG2 responses between groups 1 and 2. Significant differences in IFN-γ levels were only observed in treatment group 1 at week 2 and treatment group 2 at weeks 1 and 2 compared to the control animals. The results demonstrated that an intramuscular injection of pROP1-CD154 gene to sheep significantly enhanced their immune response and induced a mixed Th1/Th2 response while the intramuscular injection of pROP1 only induced a Th1-specific immune response.  相似文献   
24.
Gori  M.  Biricolti  S.  Pedrazzani  S.  Giordani  E.  Papini  A.  Dantur  O. R.  Arena  M. E.  Radice  S. 《Genetic Resources and Crop Evolution》2021,68(5):1799-1808
Genetic Resources and Crop Evolution - A new species of Berberis L. from the region of Tucumán (Argentina), locally known as “sacha mikuna”, was described as Berberis...  相似文献   
25.
The role of flow rate on Cd transport through a natural aquifer sand was investigated using a laboratory column set-up with particular reference to dissolution processes of external coatings. Clays and (hydr)oxides dissolution was investigated by tests performed feeding the column with Cd-free solutions at three different flow rates (0.2, 1 and 5 mL min–1). Flow rate significantly affected only the dissolution of Fe-containing coatings by releasing into the liquid phase different amounts of Fe. Cd transport experiments showed a strong effect of flow rate on Cd breakthrough curves and the lowest Cd adsorption was observed at the lowest flow rate. This behavior was fully explained in terms of competition between dissolved Fe and applied Cd for the same adsorption sites. Comparison of the Cd transport behavior on a pure quartz sand allowed confirmation of the strong influence of clay and (hydro)oxide coatings in determining the surface properties of the heterogeneous natural materials. An equilibrium model was proposed to describe the dynamic Cd behavior under the different experimental conditions (flow rates and Cd concentrations).  相似文献   
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Feline Chronic Gingivostomatitis Syndrome (FCGS) is a common disease in clinical practice. Among the therapeutic options available, long-acting corticosteroids are frequently used due to their anti-inflammatory and immunosuppressive properties. Although they may improve the clinical symptoms, they can lead to a progressive form of the disease that becomes refractory to treatment. Furthermore, their direct relationship with type II diabetes mellitus (DM) is well known. Consequently, these drugs are controversial and not recommended for routine management of FCGS. Recombinant feline interferon-omega (rFeIFN-ω) is an immunomodulatory compound. Recently, its daily oral administration has been shown to be successful in treating refractory cases of FCGS. This case study describes two clinical cases of type II DM complicated by FCGS. Both animals were calicivirus positive and they had been previously treated with long-acting corticosteroids, which may have been the major cause of DM. The two cats were treated with glargine insulin (Lantus, starting dose 1 IU/cat twice daily (BID)), achieving remission 10 and 18 weeks later respectively. Considering the difficulty with control of FCGS in these animals, an oral daily dose of rFeIFN-ω was started as an alternative to long-acting corticosteroids. In both cats oral clinical signs gradually improved and 60 days after the start of therapy the owners reported a significant relief of pain during mastication. According to the authors’ knowledge, this is the first case report that describes the successful use of rFeIFN-ω in the management of FCGS in type II diabetic cats, in which long-acting corticosteroids are contraindicated.  相似文献   
28.
Owing to the economic, social and environmental impacts associated with timber harvesting by small-scale forest owners, a number of studies have characterized their profiles, motivations and activities at a given time. However, little research has focused on how timber production has been affected by changes in the prevalence of types of forest owners over time. A 2012 telephone survey of Quebec (Canada) small-scale forest owners reveals relationships between level of harvesting and socio-demographic factors, and an evolution of these factors by examining the results of surveys conducted in 1973 and 1985. Within the same population, property size, distance between owners’ forest and homes, possession of a forest management plan, gender, education level, the length of ownership are correlated with how likely respondents were to harvest timber on their forest. Furthermore, comparison with results from previous surveys of the same population show an increase in the prevalence of characteristics associated with owners who place less importance on timber harvesting in their management decisions. Overall, since the initial survey of forest owners conducted in 1973, the size of forest holdings in Quebec has decreased, respondents’ education level has improved and the proportion of forests owned by women have increased. However, these changes are occurring at a relatively slow rate, giving government authorities time to implement policies to encourage harvesting among the new generation of forest owners.  相似文献   
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This study investigated the effect of gamma radiation on the digestibility and functional properties of rice starch. Rice cultivars IRGA417 and IAC202 were used for isolation of starch by the alkaline method. Starch samples were irradiated with 1, 2 and 5 kGy doses of 60Co at a rate of 0.4 kGy/h. A control sample, which was not irradiated, was used for comparison. Irradiated and control starches were characterized by in vitro starch digestibility, total dietary fiber, color, water absorption index, water solubility index, syneresis, swelling factor, amylose leaching, pasting properties and gel firmness. Irradiations changed starch digestibility differently in either cultivar. Increasing radiation doses promoted increase in the color parameter b* (yellow), elevation in the capacity to absorb water, and solubility in water as well as the amylose leached from granules for both cultivars. Pasting properties showed a decrease that was proportional to the dose applied, caused by the depolymerization of starch molecules. Gel firmness of the starch from IAC202 was inversely proportional to the radiation dose applied, whereas for IRGA417, there was a reduction at 5 kGy dose. Rice starches can be modified by irradiation to exhibit different functional characteristics and they can be used by the food industries in products such as soups, desserts, flans, puddings and others.  相似文献   
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