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111.
The local chemical structure of trace amounts of cadmium within microvolumes of highly inhomogeneous municipal solid waste fly ash particles was successfully monitored by means of micro-EXAFS. A new quantification procedure was developed for the evaluation of the micro-EXAFS data sets obtained from each individual particle based on a reverse Monte Carlo simulation. Evidence has been presented for the existence of cadmium silicate and cadmium chloride, with the cadmium silicate being the dominant form, and it has been demonstrated that the cadmium exists in both crystalline and amorphous states within the microspots analyzed.  相似文献   
112.
Because of the presence on the market of high-value monovarietal pasta, the aim of this work was to evaluate the potential of DNA profiling to test its authenticity. AFLP profiles obtained from eight monovarietal pasta samples and from the corresponding varieties were compared. The possibility of identifying the variety of an unknown monovarietal pasta by referring to a durum wheat molecular markers database is proposed.  相似文献   
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A study on the filtering activity has been carried out on reared specimens of the demosponge Spongia officinalis var. adriatica coming from an off-shore farm displaced off the Apulian coast (Ionian Sea). The experience was carried out under laboratory conditions, by using natural seawater collected from the sponge environment. The study demonstrates a high efficiency of the sponge in removing bacteria. Bacterial concentration significantly decreases in presence of the sponge, with a marked drop after 2 h from the start of the experience. The maximum clearance rate was 210 ml h(-1) g(-1) DW at 60 min. Retention efficiency reached the highest value of 61% at 120 min. The bacterial density removed by the S. officinalis filtering activity was 12.3 +/- 1.8 x 10(4) cells ml(-1) corresponding to a biomass of about 11.7 +/- 1.4 microg Cl(-1). The sponge fed preferentially large- and medium-size bacteria, whereas the small ones are fed after the removal of the largest size categories. The results obtained suggest that S. offcinalis is a suitable species for marine environmental bioremediation.  相似文献   
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Multiple-site colonization with Candida spp. is commonly recognized as a risk factor for invasive fungal infection in critically ill patients. We carried out a study to determine the relationship between Candida colonization and invasive infection in neurological patients admitted to an ICU. At admission (T0) and every three days for two weeks, different samples (pharynx swab, tracheal secretions, stomach contents, etc.) were collected for mycological surveillance. Candida mannan antigen and Candida anti-mannan antibodies were assayed. The Colonization Index (CI) and Corrected Colonization Index were calculated for each time point. Of all patients 70% was already colonized by Candida spp. at T0 and six of them had CI ≥ 0.5. Three patients developed candidemia; they had CI ≥ 0.5 before infection. Positive values of Candida mannan antigen and anti-mannan antibodies were found only in the patients with candidemia. The sensitivity and specificity of the Candida mannan test were 66.6% and 100%, respectively, while the sensitivity and specificity of the anti-mannan antibody test were 100%. In accordance with other authors, we find the surveillance cultures are useful to monitor the Candida colonization in ICU patients. In addition, the sequential observation of anti-mannan antibodies could contribute to early diagnosis of candidiasis more than Candida mannan antigen in immunocompetent patients.  相似文献   
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We propose an analytical solution in order to explain the processes that determine the fate and behavior of the viruses during transport in a fractured aquifer at Salento (Italy). The calculations yield the efficiency of filtration in fractures at a site near Nardo? (Southern Italy) in reducing the numbers of enteric viruses (i.e., Enteroviruses and Norovirus) in secondary municipal effluents that have been injected in the aquifer over the period 2006-2007. The model predicted, by a theoretical expression, the time-dependent rate of virus reduction, which was in good agreement with field data. The analytical solution yields the achievable "Log reduction credits" for virus reduction in wells located at the setback distances that are usually adopted in local drinking water regulations. The resulting new analytical formula for the time-dependent reduction of viruses during subsurface transport can easily be applied in health risk-based models used to forecast the spread of waterborne diseases and provides appropriate criteria (i.e., distances) needed to meet standards for the quality of drinking water derived from undisinfected groundwater.  相似文献   
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Strawberries represent a valuable source of bioactive compounds including vitamin C, E, β-carotene, and phenolic compounds, but they are fruits with an extremely short postharvest life. Therefore, the current study was conducted to investigate the effectiveness of an active coating consisting in antifungal microparticles obtained by spray drying of peony extracts (Paeonia rockii (PPR)) dispersed in chitosan (Ch) and subsequent addition to polysaccharide gels to slow the fungal attack of small highly perishable fruits, such as strawberries. The results of the antimicrobial assays indicate that the peony extracts in chitosan are able to counteract effectively the growth of different fungal isolates from deteriorated strawberries. In conclusion, through the treatment with this antifungal coating, it is possible to prolong the shelf life of delicate fruits, such as strawberries, to about 16 days, slowing down the weight loss, affecting the safeguard of important vitamins and antioxidant capacity during storage, without causing any significant alteration of the nutritional and sensorial properties of the product.  相似文献   
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