Federica Zanetti

Phytoremediation trials on metal- and arsenic-contaminated pyrite wastes (Torviscosa, Italy).

At a site in Udine, Italy, a 0.7m layer of As, Co, Cu, Pb and Zn contaminated wastes derived from mineral roasting for sulphur extraction had been covered with an unpolluted 0.15m layer of gravelly soil. This study investigates whether woody biomass phytoremediation is a realistic management option. Comparing ploughing and subsoiling (0.35m depth), the growth of Populus and Salix and trace element uptake were investigated in both pot and field trials. Species differences were marginal and species selection was not critical. Impaired above-ground productivity and low translocation of trace elements showed that bioavailable contaminant stripping was not feasible. The most significant finding was of coarse and fine roots proliferation in surface layers that provided a significant sink for trace elements. We conclude that phytostabilisation and effective immobilisation of metals and As could be achieved at the site by soil amelioration combined with woody species establishment. Confidence to achieve a long-term and sustainable remediation requires a more complete quantification of root dynamics and a better understanding of rhizosphere processes.

Conservative management of deep neck abscesses in adults: The importance of CECT findings

OBJECTIVES: To review cases of DNAs with special emphasis on contrast-enhanced computed tomography (CECT) findings and their implications for treatment planning. STUDY DESIGN AND SETTINGS: Retrospective evaluation of adult patient records with diagnosis of DNAs on CECT at Treviso Regional Hospital. RESULTS: Eighty patients were identified. In 30.0% of cases, an immediate surgical drainage was performed. In 22.5% of cases, a surgical drainage was necessary because of the lack of clinical response to medical therapy alone. Almost half of the patients were treated with antibiotics alone with complete remission. DM was predictive for lack of response to medical therapy alone (P = 0.014). Intraoperative findings confirmed the CECT diagnosis in 88.1%. CONCLUSIONS: Although the mainstay of treatment for deep neck abscesses remains surgical drainage, small abscesses can respond to antibiotics alone. CECT monitoring of DNAs was the essential steps in choosing the more appropriate treatment and, probably, the basis for the good prognosis of patients.

Pattern of lymph node metastases in squamous cell carcinoma of the tonsil : Implication for selective neck dissection

The aim of this study was to prospectively analyze the distribution of neck metastases and the outcome in patients surgically treated for tonsillar carcinoma in order to deduce implications for selective neck dissection. The criteria for inclusion in the study were (1) previously untreated, histologically proven, resectable squamous cell carcinoma of the tonsil, (2) curative surgical intent on the primary tumor and neck, (3) no history of prior head and neck cancer, (4) absence of synchronous second primary in the upper aerodigestive tract, lung and esophagus, (5) absence of distant metastases. Fifty-eight previously untreated consecutive patients with tonsillar squamous cell carcinoma were included in this prospective study. Among 22 patients with clinically negative cervical lymph nodes, 4 patients (18.2%) had metastatic lymph nodes on pathologic examination. Occult node metastases were mainly located in ipsilateral II level. No occult metastases occurred at levels I and V. Among 36 patients with clinically positive cervical lymph nodes, 3 patients (8.3%) had an occult pathologic metastatic involvement of cervical lymph nodes of ipsilateral level V. Level I was free of lymph node metastases. Clinical N category >N2a (p=0.003), nodal metastases to levels III (p=0.026) and IV (p=0.009) were significantly related to level V nodal metastases. The 2 and 5 years actuarial disease-free survival was 82.7% (95% CI 71.2-93.5%) and 58.3% (95% CI 36.7-79.9%), respectively. The actuarial recurrence-free survival was 87.9% (95% CI 78.9-96.8%) and 72.2% (95% CI 53.9-90.5%) at 2 and 5 years, respectively. Our findings support the role of a selective lateral neck dissection in the management of clinically N0 necks and in selected N+ necks (N1 and N2a disease located at level II) in patients with tonsillar carcinoma without oral involvement.

Studying root distribution with geostatistics

Abstract Geostatistics was applied to a set of RLD (Root Length Density) data of maize obtained from auger sampling. A reciprocal linear-logarithmic function was found to fit the spatial trend of RLD, and was subtracted from the original data for correct application of geostatistics. Subsequent use of variography enabled description of the relations of root density with space and provided information on the size of root clusters. Spatial relations also served as a basis for subsequent estimation by kriging of RLD in unsampled locations, thus yielding bi-dimensional RLD maps with higher accuracy than those obtained by traditional methods of interpolation. Comparing two maize hybrids of different yields, the maps showed substantial differences in the proportion of root length in peripheral positions of the cross-row vertical profile and in the incidence of zones with critical density of colonisation. The trend of variograms also indicated larger root clusters in the higher-yielding hybrid, together with more uniform colonisation of soil – a profitable feature in conditions of limited soil resources. The trial highlighted some drawbacks in the application of geostatistics to feasible schemes of soil-coring in wide-spaced crops.

Adaptability and Sustainable Management of High-Erucic Brassicaceae in Mediterranean Environment

The use of high-erucic acid oils is currently receiving increasing attention, due to the great interest in chemical compounds derived from “green feedstock”. At world level, the production of these raw materials is constantly growing, and a real niche market has progressively been created (Mosca & Boatto, 1994). This scenario will allow greater substitution of chemicals with “green” compounds, and the introduction of industrial oilcrops may lead to further expansion of the green market. Alternative uses of crops for nonfood purposes may be an interesting source of profit for farmers, as is happening for higherucic acid oils. The current demand for these oils is still limited: at world level, it is nearly 20,000 tonnes of erucic acid, corresponding to about 57,000 tonnes of oils, used for deriving erucamide and various others chemical compounds (Figure 1).