A geo-chemo-mechanical study of a highly polluted marine system (Taranto, Italy) for the enhancement of the conceptual site model.

The paper presents the results of the analysis of the geo-chemo-mechanical data gathered through an innovative multidisciplinary investigation campaign in the Mar Piccolo basin, a heavily polluted marine bay aside the town of Taranto (Southern Italy). The basin is part of an area declared at high environmental risk by the Italian government. The cutting-edge approach to the environmental characterization of the site was promoted by the Special Commissioner for urgent measures of reclamation, environmental improvements and redevelopment of Taranto and involved experts from several research fields, who cooperated to gather a new insight into the origin, distribution, mobility and fate of the contaminants within the basin. The investigation campaign was designed to implement advanced research methodologies and testing strategies. Differently from traditional investigation campaigns, aimed solely at the assessment of the contamination state within sediments lying in the top layers, the new campaign provided an interpretation of the geo-chemo-mechanical properties and state of the sediments forming the deposit at the seafloor. The integrated, multidisciplinary and holistic approach, that considered geotechnical engineering, electrical and electronical engineering, geological, sedimentological, mineralogical, hydraulic engineering, hydrological, chemical, geochemical, biological fields, supported a comprehensive understanding of the influence of the contamination on the hydro-mechanical properties of the sediments, which need to be accounted for in the selection and design of the risk mitigation measures. The findings of the research represent the input ingredients of the conceptual model of the site, premise to model the evolutionary contamination scenarios within the basin, of guidance for the environmental risk management. The study testifies the importance of the cooperative approach among researchers of different fields to fulfil the interpretation of complex polluted eco-systems.

Corneal temperature changes during photorefractive keratectomy using the Laserscan 2000 flying spot laser.

PURPOSE: To evaluate the thermal variations during photorefractive keratectomy (PRK) induced by a Laserscan 2000 flying spot excimer laser. METHODS: Thermal changes during PRK were recorded using a non-contact infrared thermometer on 58 eyes with an attempted correction ranging from -1.25 to -9.00 D. The eyes were randomly divided into two groups to test the thermal effects of two different ablation scan techniques: sequential and randomized modes. Thermal measurements were also performed during myopic ablations on polymethylmethacrylate (PMMA) test plates. RESULTS: On PMMA plates, a significant relationship between the amount of attempted myopic correction and thermal changes was established (P=.017 in sequential mode and P=.007 in randomized mode); this was not established for human eyes. With the sequential mode, an unexpected cooling effect after PRK was reported for each myopia subgroup (P=.003 in the low and high myopia subgroups, P<.001 in the medium myopia subgroup). With the randomized mode, the cooling effect was detected only for low amounts of myopia. CONCLUSION: Despite a high repetition rate, the Laserscan 2000 flying spot laser minimized thermal shock. In comparison with randomized (nonsequential) pulse application, sequential pulsing showed no increase in the thermal loading of corneas. In fact, a cooling effect during PRK was produced.

Retinal nerve fiber layer measurements using scanning laser polarimetry after photorefractive keratectomy.

PURPOSE: To assess the effects of corneal depth changes on retinal nerve fiber layer (RNFL) postoperative measurements in myopic patients who had undergone photorefractive keratectomy (PRK). METHODS: A total of 120 myopic patients underwent PRK for myopia (range -2 to -10 diopters) and were divided into three groups according to their myopic correction: lower than 3 diopters (low myopia group), between 3 and 6 diopters (medium myopia group), over 6 diopters (high myopia group). RNFL parameters were evaluated preoperatively and 5 days, 3 months and 6 months after surgery, using a GDx NFA II scanning laser ophthalmoscope. RESULTS: Significant changes were seen in the symmetry, superior maximum, and average thickness, comparing baseline with six-month measurements (p=0.008, 0.027, 0.015 respectively). Dividing the sample according to attempted myopic correction, it was found that mean postoperative RNFL thickness was significantly lower after PRK only in the high myopia group. Mean RNFL thickness did not change with time (p=0.884). Ablation depth was correlated with a change in RNFL thickness by the sixth postoperative month for each group. These variables were significantly related only in the high myopia group (p=0.003). CONCLUSIONS: As polarised light penetrates the ablation area, morphological and functional changes might affect Gdx NFA II measurements. It must always be borne in mind that RNFL thickness can decrease either in cases of glaucoma or after PRK for high myopia, so close attention must be paid to interpreting these measurements in patients who have undergone PRK.

Use of recombinant factor VIIa (NovoSeven) in the treatment of two patients with type III von Willebrand's disease and an inhibitor against von Willebrand factor.

Two siblings affected by type III von Willebrand's disease with precipitating alloantibodies against von Willebrand's factor (vWF) and not susceptible to treatment with factor VIII/vWF concentrates received recombinant activated factor VII for oral surgery. This therapy, combined with antifibrinolytic drugs and local application of fibrin glue, seems to be effective and safe. It may be considered a promising approach to the management of this rare condition.