Residual Strength Parameters From a Slope Instability

The study attempts to determine the in situ shear strength parameters of a stiff clay from a back analys1s of a well documented landslide. The relatively small extension of the instability, as well as the homogeneity of the clay formation and the defined slip surface, allows a consistent evaluation of shear strength parameters. The study is also supported by ring shear tests, and microscopic analysis performed on undisturbed thin sections, by means of scanning electron microscopy. The results of back analysis are in good agreement with laboratory tests and microscopy observations

Trigeminal neuralgia and persistent trigeminal artery

We report a case of trigeminal neuralgia caused by persistent trigeminal artery (PTA) associated with asymptomatic left temporal cavernoma. Our patient presented unstable blood hypertension and the pain of typical trigeminal neuralgia over the second and third divisions of the nerve in the right side of the face. The attacks were often precipitated during physical exertion. MRI and Angio-MRI revealed the persistent carotid basilar anastomosis and occasionally left parietal cavernoma. After drug treatment of blood hypertension, spontaneous recovery of neuralgia was observed and we planned surgical treatment of left temporal cavernoma

Nanoscale Metallic Iron for Environmental Remediation: Prospects and Limitations

The amendment of the subsurface with nanoscale metallic iron particles (nano-Fe0) has been discussed in the literature as an efficient in situ technology for groundwater remediation. However, the introduction of this technology was controversial and its efficiency has never been univocally established. This unsatisfying situation has motivated this communication whose objective was a comprehensive discussion of the intrinsic reactivity of nano-Fe0 based on the contemporary knowledge on the mechanism of contaminant removal by Fe0 and a mathematical model. It is showed that due to limitations of the mass transfer of nano-Fe0 to contaminants, available concepts cannot explain the success of nano-Fe0 injection for in situ groundwater remediation. It is recommended to test the possibility of introducing nano-Fe0 to initiate the formation of roll-fronts which propagation would induce the reductive transformation of both dissolved and adsorbed contaminants. Within a roll-front, FeII from nano-Fe0 is the reducing agent for contaminants. FeII is recycled by biotic or abiotic FeIII reduction. While the roll-front concept could explain the success of already implemented reaction zones, more research is needed for a science-based recommendation of nano- Fe0 for subsurface treatment by roll-front

Stabilità idraulica dei geotessili nontessuti impiegati come filtri in condizioni di flusso unidirezionale.

Memorie e studi dell'Istituto di Costruzioni Marittime e di Geotecnica dell'Università di Padov