This paper presents the results of an extensive set of laboratory experiments performed to design a demonstrative electrokinetic plant for extracting heavy metals from marine sediments dredged from ...the Livorno marine harbour. The investigated sediments displayed a high salinity, a high acid neutralization capacity, a low electrical resistivity (0.5Ωm), a high alkalinity (pH≈8) and a large fraction of fine particles. The target metals were Cd, Cr, Cu, Ni, Pb and Zn at relatively weak and inhomogeneous concentrations with high non-mobile fractions. After an accurate characterization, several screening and full electrokinetic tests were performed using cells of two different sizes, several conditioning agents (HNO3, HCl, H2SO4, citric acid, oxalic acid, ascorbic acid, EDTA), different applied current intensities and durations. The tests highlighted the need for long treatment times in order to obtain a significant pH reduction, with some appreciable metal removal being attained only after several weeks. The best results were obtained with strong acids used as the conditioning agents, with significant specific effects of each acid, including pronounced resistivity increase (from 0.5 up to 10Ωm) and a high electroosmotic flow (EOF) with H2SO4, or a reversed EOF (electroendosmosis), and minor resistivity changes with HNO3. The use of the obtained data to design a demonstrative plant is also presented in the paper, with considerations on operating parameters such as energy and reagent consumption, characteristics of plant components and required safety measures.
Highlights • Surgery for flexible adult flatfoot deformity has been advocated for years. • There are less than 20 published studies that evaluate the outcome of this type of surgery. • We found ...significant improvements in AOFAS and VAS-FA from pre-operative to 34 months after surgery for flatfoot. • Arthroereisis and tensioning of the posterior tibial tendon provided good functional outcomes for patients under 60 years of age having stage IIA flexible flatfoot without arthritic manifestations.
The Er:YAG laser has proven particularly efficient in cleaning procedures of works of art. The removal of the superficial deposits is achieved through melting, thermal decomposition and evaporation. ...However, the energy absorbed by vibrational modes is dissipated as heat, increasing the temperature of the surface coating that could cause damage on the object. The aim of this study was to evaluate the temperature increase induced by a Er:YAG MonaLaser (LLC., Orlando, FL, USA). To that purpose, we designed a dedicated device to perform the tests in an inert atmosphere or with a wetting agent, to measure the radiant energy per laser pulse. Tests were carried out both on graphite, which absorbs IR radiation and showed a very intense flash emission, and on different kind of samples representative of materials with different levels of conductivity and thermal diffusivity. Results obtained showed that the temperature increase in the irradiated surface depends on the substrate but never causes the damage of the organic and inorganic material. The use of a solvent as wetting agent has been also tested.
Over the last few years, breath analysis for the routine monitoring either of metabolic disorders caused by specific diseases or occupational exposure to toxic substances has become more and more ...attractive due to its noninvasiveness.
Several approaches have been proposed for sample collection, treatment, and analysis. This paper gives a critical overview of the analytical devices and procedures used for breath analysis. Results on the identification of chemicals in human breath for a selection of diseases are discussed.
Nalophan, Tedlar and Cali-5-Bond polymeric bags were compared to determine the most suitable type for breath sampling and storage when volatile organic compounds are to be determined. Analyses were ...performed by thermal desorption gas chromatography mass spectrometry. For each bag, the release of contaminants and the chemical stability of a gaseous standard mixture containing eighteen organic compounds, as well as the CO2 partial pressure were assessed. The selected compounds were representative of breath constituents and belonged to different chemical classes (i.e. hydrocarbons, ketones, aldehydes, aromatics, sulfurs and esters). In the case of Nalophan, the influence of the surface-to-volume ratio, related to the bag's filling degree, on the chemical stability was also evaluated. Nalophan bags were found to be the most suitable in terms of contaminants released during storage (only 2-methyl-1,3-dioxalane), good sample stability (up to 24 h for both dry and humid samples), and very limited costs (about 1 € for a 20 liter bag). The (film) surface-to-(sample) volume ratio was found to be an important factor affecting the stability of selected compounds, and therefore we recommended to fill the bag completely.
Background
Ataxia is a rare neurological condition causing a deficit in the coordination of motor activities, preventing the fluidity of movements. Children with ataxia may show several different ...ataxic signs, along with difficulties in walking autonomously and ataxic gait often associated with trunk instability. Ataxic signs can be either acute or chronic, and in either case, the diagnosis can be extremely complex. Symptoms and their etiology are often widely heterogeneous, even within the same condition.
Methods
The guideline was developed based on the methodology defined by the Methodological Handbook of the Italian National Guideline System (SNLG) and was reported following the AGREE-II checklist. The SNLG methodology required the adoption of the GRADE approach for the whole development process. To facilitate the implementation of the contents and recommendations from the guideline, two care pathways were developed based on the NICE and the European Pathway Association (EPA) models.
Results
The guideline included 28 clinical questions, 4 on the identification and management of acute ataxias, and 24 on the diagnosis and management of chronic ataxias. The document included 44 recommendations, 37 clinical recommendations, and 7 recommendations for research.
Conclusion
The working group, despite the lack and methodological limitations of the evidence, deemed as essential to provide indications and recommendations, in particular in some clinically relevant areas. The care pathway was produced as a tool to facilitate the implementation of the contents and recommendations. The interactive version of the pathway is available on the SNLG website along with a leaflet dedicated to families and caregivers.
An innovative procedure for the on-line coupling of ion chromatography with graphite furnace atomic absorption spectrometry is described, which is particularly effective for the determination of ...trace metals in seawater samples. The Capillary Injection Device (CID) is used as an interface which allows the eluent to be transferred from the chromatographic column into the graphite tube at a flow rate of as high as 2 ml/min. The analytical procedure is based on the metal complex formation with 8-hydroxyquinoline in the sample solution, followed by the preconcentration of the complexes in a chromatographic column packed with XAD-2 resin. The complexes were then eluted from the column with methanol, and quantitatively injected into the furnace. The procedure was validated by determining cadmium and lead in certified reference seawater samples at a level of 30–40 pg/g, with a typical reproducibility of 10% and an accuracy of better than 5%. Finally, it was tested on a real sample of seawater. Due to the high reproducibility, a pg/g concentration level can be measured.
The bisphosphonates are the most commonly prescribed antiresorptive drugs for the treatment of metabolic disorders. However, there are several adverse effects associated with oral bisphosphonates ...including the bisphosphonate related osteonecrosis of the jaw (BRONJ). Several risk factors drug-related, local and sistemic factors have been linked to BRONJ. A more recent report described an absolute risk ranging from 0.46% to 0.99% among patients receiving oral bisphosphonates. In this paper, the osteonecrosis of the jaw associated with oral BP therapy in patients affected by osteometabolic disorders was reviewed in order to renew the current knowledge. Each patient was clinically examined and a detailed medical history was raised. The majority (8/12) were prescribed alendronate, 2 oral ibandronic acid; 1 a. risendronico; in 8 patients, the osteoporosis was associated with systemic risk factors as Diabete, Rheumatic disease, Hypothyroidism, Hepatitis C Virus Infection and supportive therapy. In 10 cases the duration of oral BP therapy exceeded 5 years prior to BRONJ diagnosis.
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