The paper deals with the rehabilitation of an historical masonry bridge crossing the Magra river and connecting the small towns of Mulazzo and Villafranca in the northern part of Tuscany (I).
The ...masonry arch bridge, characterized by eight arches spanning 19 m around each and by around 12 m height intermediate masonry piers on shallow foundations, was built in 1874.
Since the original carriageway width was not sufficient to allow two lanes, in 1961 it was widened by means of two lateral prestressed concrete beams, supported by the piers, so hiding the arches and modifying severely the original aspect of the bridge itself.
In 2011, during the Magra flooding, two arches on the Mulazzo side collapsed due to scour of the extreme pier.
The reconstruction of the collapsed arches and rehabilitation and the strengthening of the bridge, which has been completed last year, is discussed and the execution of the interventions, which has performed without erection of temporary support in the riverbed, is also illustrated.
Particular attention is devoted to the original solutions which have been adopted for the full seismic upgrading of the bridge according to the Italian Building Code currently in force, recovering the original architectural aspect of the bridge and widening the carriageway as well.
Melanomas are skin tumors that show a variety of biological behavior. Some develop very fast and some other grow extremely slow, with metastasis appearing, eventually, many years after the diagnosis. ...The number of mitoses in primary melanoma has been related to a more aggressive tumor and may have a potential as predictive factor for cutaneous melanoma survival. However, tumor mitotic rate is a static measure and in multivariate analysis on tumor survival, it has scored less than other tumor characteristics. We tried to evolve tumor mitotic rate from a static parameter to a time‐dependent one. Similar to the already described growth rate (GR), we propose the speed rate (SR). SR is defined as the ratio of tumor mitotic rate to time to melanoma development. A prospective series of 345 patients with melanoma was investigated for the role of SR as predictive factor for sentinel lymph node (SLN) positivity and tumor progression. We calculated the best threshold for SR and GR to predict the risk of recurrence. Melanoma clinical and histological characteristics as well as GR were correlated in a multivariated analysis with SR. SR values >0.2 mitoses/month were associated with negative prognostic factors such as ulceration (82.8%), SLN positivity (80%), progression (82.8%), and death (85.7%). The association of GR > 0.3 mm/months and SR > 0.2 mitoses/month had a significant predictive value in terms of SLN positivity, progression, and recurrence‐free survival. We propose SR as a new “dynamic” predictor of histological SLN positivity and melanoma recurrence risk. We think that he association with this new feature with GR may be helpful in improving the accuracy of predicted clinical outcome of patient especially with thin melanomas.
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