Five soil-size aggregate fractions, corresponding to coarse (500–840 μm), medium (200–350 μm), fine (75–200 μm) sand, silt (10–75 μm) and clay (<4 μm), were artificially contaminated with diesel ...fuel, and thermally treated using a laboratory-scale apparatus to investigate the effects of soil texture on contaminant removal. Specifically, an ex situ thermal process was simulated using helium as carrier gas at a pressure of 1.0 atm, a flow rate of 1.5 L·min⁻¹ and different temperatures (100–300 °C). Soil specimen and carrier gas temperature in different experimental apparatus sections were monitored. The amount of contaminant sorbed and contaminant residual concentration in soil (as n-alkanes compounds C₁₀–C₂₅) were determined by gas chromatography. The main results show that soil texture influences contaminant sorption phenomena and remediation processes in thermal desorption treatment. Contaminant removal was affected by soil texture (variation up to 37.1%), and fine sandy soil exhibited the highest desorption extent of diesel fuel for a thermal treatment of 30 min. Results are of practical interest and may be used in scaling-up and designing of desorption systems for preliminary cost and optimal condition assessment.
Volcanic ash (VA) fallout during explosive activity of Mt. Etna (Sicily, Italy) negatively impacts the economy of local municipalities due to the management and disposal costs. In order to ...investigate an alternative use of VA in the civil and environmental engineering field, zeolites synthetized from VA were employed to remove ammonium from various aqueous solutions. Specifically, batch adsorption experiments were conducted to assess the effect of different synthesis conditions (e.g., incubation temperature, use of seawater or distilled water, VA particle size) on the adsorption capacity of ammonium on the produced zeolites. Adsorption isotherms were well fitted by Freundlich model and showed that zeolite synthetized at 70 °C using distilled water (C1H70) exhibited the highest adsorption capacity (~18.4 mg g−1). The observed ammonium adsorption capacity is higher or comparable to other natural or synthetized zeolites reported in literature. C1H70 was used in column experiments under different operational conditions, including initial ammonium concentration (10 and 40 mg L−1), empty bed contact time (EBCT, 4 and 8 min) and water quality (deionized water vs. secondary effluent wastewater). The Dose-Response model showed the best fitting in describing the breakthrough curves. Obtained results showed a good removal of ammonium even though the adsorption capacity decreased in presence of competing ions (e.g., calcium) and when tap water or wastewater was used. Moreover, the adsorption capacity of C1H70 regenerated through NaCl solution was found similar to the fresh C1H70. However, the regenerated zeolite was characterized by a slower mass transfer process. Overall, synthetized zeolites from VA can be used to remove ammonium from wastewater, reducing both the landfilling of VA and the extraction of natural zeolite under the circular economy perspective.
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•Zeolite synthetized from Mt. Etna volcanic ash was tested for ammonium removal.•Adsorption capacity depends on synthesis conditions (incubation temperature, water).•Seawater led to precipitate halite on zeolite and a lower adsorption capacity.•The complexity of real wastewater impacted the zeolite efficiency.•Zeolite regenerated trough NaCl solution is characterized by slower mass transfer.
The limits of microwave (MW) heating in situ application for the remediation of hydrocarbon-polluted soils have been investigated by means of a dedicated simulating model. A computer code was ...expressly developed and applied to simulate the physical phenomena induced by a MW treatment. MW process was modelled by means of the mono-dimensional transient equations of energy, taking into account the interaction between the electromagnetic field and soil and conductivity phenomena. The model was validated by comparison with experimental results from lab-scale activities. Simulations investigated the influence of soil texture and moisture and operating conditions on electric field penetration into the soil and inducted soil temperature profiles.
Main results indicate that all investigated parameters significantly influenced the effectiveness of the heating process. In generally, the sandy soil appeared to be more penetrable by MWs respect to the clayey one and higher electric field and soil temperature values were found for the sandy soil with the lower water content. Results also revealed that, for the successful remediation of a clayey soil, a maximum distance of 76cm should be considered when applying an incident electric field of 1000Vm−1 for 15days, whereas a higher distance of 101cm can be taken in consideration in the case of sandy soil. A further slight distance increase can be achievable in the case of lowest-moisture soil (5%). Overall, the general performance of the treatment can be greatly improved by increasing the incident electric field to a value 1500Vm−1. In this case, a 15-day heating of a sandy soil led to the maximum distance calculated of 145cm. Obtained results are of scientific and practical interest and represent the basis for further technical, energy and economic studies, useful to better define the limits of the in situ MW treatment real applicability. The proposed model, giving good prediction of the experimental data for electric field and soil temperature variation, represents a powerful and suitable tool to predict the impact of operating conditions on the effectiveness of the MW techniques.
•We develop and apply a computer code to simulate an in situ soil MW-irradiation.•We validate the model with lab-scale experimental data.•We investigate the influence of soil properties and operating conditions on in situ effectiveness.•Sandy soils and low soil moisture appeared to result in a higher effective treatment•Results can be used for energy and economic studies and to designing activities.
The aim of the research is to apply a biosurfactant-enhanced-EK technology to marine sediment contaminated by high level of Hg. In this work, data from batch-tests using different novel biosurfactant ...agents were reported. In addition, a dedicated EK bench-scale apparatus was designed and carried out. Technical test was also performed to evaluate the optimal operating features of the EK bench-scale apparatus, assessing the influence of applied voltage and treatment time on the current intensity and electroosmotic flow. Batch experiments were conducted using two sugar esters as biosurfactants and EDTA salt at different concentrations. Results showed that the maximum extraction efficiency was observed for the biosurfactant Olimpicon GC (15%), for which the Hg extraction was shown to be 3.6-fold higher than for 0.2 M EDTA. From technical tests, the observed reduction of current intensity and electroosmotic flow with time highlights the necessity of using conditioning agents during the treatment. Data demonstrates also the good working features of the experimental apparatus. Preliminary results show that EK treatment jointly with biosurfactants such as sugar esters could be a better choice for the remediation of Hg-polluted sediments. The results obtained are of scientific and practical interest and can be used for further researches.
In this study different water saving measures (structural and non-structural) were implemented in different urban buildings. A monitoring program of water consumption was carried out to verify and ...compare the effectiveness of high-efficiency plumbing fixtures and educational programs in different types of buildings (two residential houses, two Middle Schools and two Sport Centres) located in a drought experienced region (Sicily, Italy). In all cases, relevant water conservation percentages were achieved with prominent values in public buildings. The highest water conservation (up to 60%) was observed in two Middle Schools, where a large amount of water was wasted. Overall, the structural measures led to high water conservation, while the educational programs did not always improve the water saving effectiveness. These results highlight that in some urban areas the awareness of water conservation is not well established and large volumes of water are wasted, especially in public buildings, due to faulty plumbing fixtures. Governments and Environmental Agencies should promote with more effort water saving measures in order to support green building policy and global sustainability.
The main objective of this study was to compare the energy cost-effectiveness of two innovative techniques, namely microwave (MW) heating and electrokinetic (EK) decontamination for the successful ...remediation of highly Hg-contaminated marine sediments from Augusta Bay (Sicily, Italy).
Bench-scale experiments were conducted and obtained results were used to elaborate energy and economic considerations aimed at selecting the most effective and economic approach.
Results revealed that without any appropriate conditioning agents, very poor contaminant mobilization can be achieved by EK due to the high percentage of carbonates, as sediment mineral, and high organic matter and sulphides. The best Hg-removal (∼71% in 400 h) was achieved using both methylglycinediacetic acid (MGDA) and polyoxyethylene (20) sorbitan monooleate (Tween 80) as processing agents. Related Hg residual concentrations exceed the desired regulatory limit of 1 mg kg−1 for Augusta Bay. Simulated MW heating showed the achievement of a very rapid sediment temperature increase (∼64 °C min−1, maximum ∼450 °C), mainly due to the mineral composition of the sediments and their high salinity. This jointly with the addition of both MGDA and Tween 80, led to a very low residual Hg concentration of 0.56 mg kg−1 (R = ∼99%) after 7-min treatment.
Calculations from energy and economic analysis revealed that a specific energy consumption of 6.73 kWh ton−1, which corresponds to an energy cost of 0.81 € ton−1, is required for the EK, whereas slightly higher values (32.97 kWh ton−1 and 3.96 € ton−1) were assessed for MW heating. Therefore, the higher Hg-removal obtainable in such a short remediation time by MW heating along with its with other advantages offset a low specific energy cost increase, making this technique a preferable choice for the remediation of Hg-contaminated marine sediments such as those present in Augusta Bay.
To test the hypothesis that nailfold capillaroscopy can noninvasively detect dysregulated retinal angiogenesis and predict retinopathy of prematurity (ROP) in infants born premature before its ...development.
In a cohort of 32 infants born <33 weeks of gestation, 1386 nailfold capillary network images of the 3 middle fingers of each hand were taken during the first month of life. From these, 25 infants had paired data taken 2 weeks apart during the first month of life. Images were analyzed for metrics of peripheral microvascular density using a machine learning–based segmentation approach and a previously validated microvascular quantification platform (REAVER vascular analysis). Results were correlated with subsequent development of ROP based on a published consensus ROP severity scale.
In total, 18 of 32 (56%) (entire cohort) and 13 of 25 (52%) (2-time point subgroup) developed ROP. Peripheral vascular density decreased significantly during the first month of life. In the paired time point analysis, vessel length density, a key metric of peripheral vascular density, was significantly greater at both time points among infants who later developed ROP (15 563 and 11 996 μm/mm2, respectively) compared with infants who did not (12 252 and 8845 μm/mm2, respectively) (P < .001, both time points). A vessel length density cutoff of >15 100 at T1 or at T2 correctly detected 3 of 3 infants requiring ROP therapy. In a mixed-effects linear regression model, peripheral vascular density metrics were significantly correlated with ROP severity.
Nailfold microvascular density assessed during the first month of life is a promising, noninvasive biomarker to identify premature infants at highest risk for ROP before detection on eye exam.
Food Neophobia in Childhood Affects Dietary Variety FALCIGLIA, GRACE A; COUCH, SARAH C; GRIBBLE, LAURA SIEM ...
Journal of the American Dietetic Association,
12/2000, Letnik:
100, Številka:
12
Journal Article
Objective To determine whether children with food neophobia (unwillingness to try new foods) have more restrictive diets than children without neophobia.
Subjects Seventy children were classified ...into 3 groups based on scores obtained on the Food Neophobia Scale: neophobic group, score greater than 41; neophilic group, score less than 27; and average group, score of 28 to 40.
Design Dietary data were collected and analyzed for 3 days selected randomly. The dependent variables measured were energy and nutrient intakes, servings of each Food Guide Pyramid group, and Health Eating Index (HEI) scores.
Statistical analyses χ
2, 1-way analysis of covariance, and Scheffe multiple comparisons tests were conducted.
Results The 3 groups were similar with respect to the number of children meeting two thirds of the RDA/DRI for energy and most nutrients. The exception was vitamin E: fewer neophobic children met two thirds of the recommended value for this nutrient than average and neophilic children. The overall HEI score was significantly lower for the neophobic group compared with the average and neophilic groups. The HEI index showed that children with neophobia had a higher intake of saturated fat and less food variety than children without food neophobia.
Applications Dietitians should emphasize increased food variety for children within the context of a healthful diet. Research should be conducted to determine the effects of dietary variety on quality of diet and health of children.
J Am Diet Assoc. 2000;100:1474-1478,1481.
Laryngotracheitis is a common disease, mainly characterized by dysphonia, cough, and sore throat. The diagnosis is usually based on the clinical ground, and antibiotic therapy is frequently used in ...clinical practice. However, antibiotics frequently induce intestinal dysbiosis associated with some clinical problems. The current clinical experience was conducted in patients with pharyngotonsillitis and treated with antibiotics. A one-month course of a probiotic mixture (Abincol® containing Lactobacillus plantarum LP01 (1 billion of living cells), Lactobacillus lactis subspecies cremoris LLC02 (800 million living cells), and Lactobacillus delbrueckii LDD01 (200 million living cells), was prescribed in the Group A, and was compared with no add-on treatment, such as the Group B. Patients were evaluated at baseline (T0), at the end of antibiotic treatment (T1), at the end of probiotic course (T2), and at the end of 3-month follow-up (T3). Globally, 833 outpatients with laryngotracheitis were enrolled: 425 in Group A and 408 in Group B. All of them were treated with a 7-10-day course of antibiotic therapy. The probiotic mixture reduced the duration of symptoms associated with antibiotic therapy already at the end of the antibiotic cycle. The intergroup comparison showed that probiotic group patients experienced less fever, tiredness, headache, pain, malaise, diarrhea, and nausea (p<0.001 for all) than control patients at T1. The probiotic course reduced the possible clinical relapse, and the use of additional medications at T2 and T3. In conclusion, the present clinical experience demonstrated that a probiotic mixture containing Lactobacillus plantarum LP01, Lactobacillus lactis subspecies cremoris LLC02, and Lactobacillus delbrueckii subspecies delbrueckii, was able to rapidly reduce symptoms associated with antibiotic therapy in patients with laryngotracheitis.
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