Search

The purpose of the present document is to provide detailed information on the correct and optimal use of digital media to ensure continuity of care for gastroenterological patients in everyday clinical practice, in health emergencies and/or when the patient cannot reach the hospital for other reasons. During the recent COVID-19 pandemic, telemedicine has allowed many patients with chronic diseases to access remote care worldwide, proving to be the ideal solution to overcome restrictions and carry out non-urgent routine follow-ups on chronic patients. The COVID-19 pandemic has therefore made organizational and cultural renewal essential for the reorganization of healthcare in order to ensure greater continuity of care with a minimum risk of spreading the virus to users, practitioners and their families. These AIGO recommendations are intended to provide Italian gastroenterologists with a tool to use this method appropriately, in compliance with current legislation, in particular the proper approach and procedures for conducting a remote examination using a video conferencing tool, the so-called televisit. In the near future, telemedicine may contribute to a possible reorganization of healthcare systems, through innovative care models focusing on the citizen and facilitating access to services throughout the entire Country.

Climate crisis is dramatically changing life on earth. Environmental sustainability and waste management are rapidly gaining centrality in quality improvement strategies of healthcare, especially in procedure-dominant fields such as gastroenterology and digestive endoscopy. Therefore, healthcare interventions and endoscopic procedures must be evaluated through the 'triple bottom line' of financial, social, and environmental impact. The purpose of the paper is to provide information on the carbon footprint of gastroenterology and digestive endoscopy and outline a set of measures that the sector can take to reduce the emission of greenhouse gases while improving patient outcomes. Scientific societies, hospital executives, single endoscopic units can structure health policies and investment to build a "green endoscopy". The AIGO study group reinforces the role of gastrointestinal endoscopy professionals as advocates of sustainability in digestive endoscopy. The "green endoscopy" can shape a more sustainable health service and lead to an equitable, climate-smart, and healthier future.

Esophagogastroduodenoscopy (EGD) plays a crucial role in the management of gastroduodenal diseases by allowing a direct and accurate evaluation of the mucosa and the execution of several operative maneuvers. Despite a constant development of new imaging tools and operative devices, the widespread use of EGD has not resulted in a significant reduction of mortality for patients affected by esophageal/gastric cancer during the last three decades in Western countries. Evidence indicates that this disheartening scenario derives from a high variability of execution of EGD which determines its quality and diagnostic yield, delaying the diagnosis of neoplastic diseases. Based on this evidence, in recent years many scientific societies have produced different position papers aimed at defining quality performance measures in EGD. Thus, the Italian Association of Gastroenterologists and Endoscopists, the Italian Society of Digestive Endoscopy and the Italian Society of Gastroenterology have produced this joint document based on the review of ASGE, ACG, BSG, ESGE and Asian Consensus EGD position papers with the aim of indicating the quality standards of EGD (pre-, intra- and post-procedure) focused on lesion detection to be adopted in the Italian context.

ObjectiveTo investigate the predictive value of the Diverticular Inflammation and Complication Assessment (DICA) classification and to develop and validate a combined endoscopic-clinical score predicting clinical outcomes of diverticulosis, named Combined Overview on Diverticular Assessment (CODA).DesignA multicentre, prospective, international cohort study.Setting43 gastroenterology and endoscopy centres located in Europe and South America.Participants2215 patients (2198 completing the study) at the first diagnosis of diverticulosis/diverticular disease were enrolled. Patients were scored according to DICA classifications.InterventionsA 3-year follow-up was performed.Main outcome measuresTo predict the acute diverticulitis and the surgery according to DICA classification. Survival methods for censored observation were used to develop and validate a novel combined endoscopic-clinical score for predicting diverticulitis and surgery (CODA score).ResultsThe 3-year cumulative probability of diverticulitis and surgery was of 3.3% (95% CI 2.5% to 4.5%) in DICA 1, 11.6% (95% CI 9.2% to 14.5%) in DICA 2 and 22.0% (95% CI 17.2% to 28.0%) in DICA 3 (p10% and >2.5% in CODA C, respectively. The CODA score showed optimal discrimination capacity in predicting the risk of surgery in the development (c-statistic: 0.829; 95% CI 0.811 to 0.846) and validation cohort (c-statistic: 0.943; 95% CI 0.905 to 0.981).ConclusionsDICA classification has a significant role in predicting the risk of diverticulitis and surgery in patients with diverticulosis, which is significantly enhanced by the CODA score.Trial registration numberNCT02758860.

This paper shows the results of the monitoring of the deformations of a tunnel, carried out using a distributed optical fiber strain sensor based on stimulated Brillouin scattering. The artificial tunnel of the national railway crosses the accumulation zone of an active landslide, the Varco d’Izzo earthflow, in the southern Italian Apennines. Severely damaged by the landslide movements, the tunnel was demolished and rebuilt in 1992 as a reinforced concrete box flanked by two deep sheet pile walls. In order to detect the onset of potentially dangerous strains of the tunnel structure and follow their time trend, the internal deformations of the tunnel are also monitored by a distributed fiber-optic strain sensor since 2016. The results of the monitoring activity show that the deformation profiles are characterized by strain peaks in correspondence of the structural joints. Furthermore, the elongation of the fiber strands crossing the joints is consistent with the data derived by other measurement systems. Experiments revealed an increase in the time rate of the fiber deformation in the first and last part of the monitoring period when the inclinometers of the area also recorded an acceleration in the landslide movements.

This paper reports a case study of the interaction between a slow-moving landslide in clay soil and a railway tunnel protected by sheet pile walls, that crosses the landslide accumulation. The earthflow, that develops in the Southern Apennines, Italy, has been long studied and monitored by different organizations, such as the national railway company and the University of Basilicata. Since the investigated landslide and construction typologies are quite diffused in mountainous areas, the case study can be considered representative of a large number of other similar cases. Differently from other approaches proposed in the literature, the role of the landslide slip surface depth, changing in the directions longitudinal and transversal to the tunnel, and of structural connections, affecting the pile–tunnel system response, are accounted for in detail. Several numerical models are used to simulate the interaction between the sliding soil and tunnel. Different 2D and 3D geotechnical and structural models are adopted to reproduce stress–strain scenarios compatible with the experimental evidence. The modeling results indicate that the interaction varies considerably along the tunnel length because of the 3D geometry of the landslide, and is conditioned by the residual shear strength available on the slip surface. The expansion joints in the tunnel lining only marginally influence the stress in the structure because of the presence of the adjacent sheet pile walls, which enable considerable collaboration between the tunnel sectors.

Background & Aim: Standard 10-day sequential therapy is advised as first-line therapy for Helicobacter pylori (H. pylori) eradication by current Italian guidelines. Some data suggested that a 14-day regimen may achieve higher eradication rates. This study compared the efficacy of sequential therapy administered for either 10- or 14-days.Methods: This prospective, multicenter, open-label study enrolled patients with H. pylori infection without previous treatment. Patients were receiving a sequential therapy for either 10 or 14 days with esomeprazole 40 mg and amoxicillin 1 g (5 or 7 days) followed by esomeprazole 40 mg, clarithromycin 500 mg and tinidazole 500 mg (5 or 7 days), all given twice daily. Bacterial eradication was checked using 13C-urea breath test. Eradication cure rates were calculated at both Intention-to-treat (ITT) and per-protocol (PP) analyses.Results: A total of 291 patients were enrolled, including 146 patients in 10-day and 145 in the 14-day regimen. The eradication rates were 87% (95% CI = 81.5-92.4) and 90.3% (95% CI = 85.5-95.1) at ITT analysis with the 10- and 14-day regimen, respectively, and 92.7% (95% CI = 88.3-97) and 97% (95% CI = 94.2-99.9) at PP analysis (p =0.37). Among patients, who earlier had interrupted therapy, bacterial eradication was achieved in 8 out of 9 who completed the first therapy phase and performed at least ≥3 days of triple therapy in the second phase.Conclusion: This study found that both 10- and 14-day sequential therapies achieved a high eradication rate for first-line H. pylori therapy in clinical practice.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic requires appropriate measures for containing infection spreading. Endoscopic procedures are considered at increased risk of infection transmission. We evaluated organizational aspects and personal behaviours in Italian Endoscopic Units during phase II of the pandemic. METHODS: A questionnaire on organizational aspects and use of personal protective equipment (PPE) were e-mailed to gastroenterologists working in Endoscopic Units. Data were analysed accordingly to the National Health Institute and Gastroenterology Societies recommendations. RESULTS: Data of 117 centres were collected, and different shortcomings emerged. Specific protocols for containing infection and training programs for operators were lacking in 20 and 30% of centres, respectively, and telephone triage 24-72 h before the endoscopy was not implemented in 25% of hospitals. In 30% of centres, the slot time for endoscopies and between examinations was not prolonged. PPE, masks, shirts and gloves were universally adopted, although with some differences. In 20% of centres, a FFPE-FFP3 mask was not adopted during endoscopic examinations. Postendoscopy patient tracking/contact was completed in only one-third of centres. CONCLUSIONS: Our survey provides information on organizational and medical behaviours during COVID-19 phase II in Italy, which could be useful for adopting appropriate measures for containing COVID-19 spread during phase II.

Transmission with endoscopes, particularly duodenoscope, of potential lethal infections prompted different scientific societies to deliver recommendations aimed reducing this risk. Some International societies extended recommendations on microbial surveillance to all the endoscopes and devices used in the reprocessing procedure. Considering the relevance of the topic, 8 Italian scientific societies of physicians, nurses and technical operators prepared a concerted document taking into account Institutional advisories and facilities in Italy. The rules for a correct microbial surveillance on endoscopes were detailed in term of what, how and when to perform the procedure, also suggesting behaviors in case of contamination.

The work deals with the exploitation of a distributed fiber-optic strain sensor for long-term monitoring of a railway tunnel affected by an active landslide located in southern Italy. The optical fibers have been applied to detect the strain distribution along the two walls of the tunnel. The experimental results, relative to a three years' span, show the sensor's ability to identify the location along the tunnel walls of potentially dangerous strained regions and follow their temporal evolution, as well.

With reference to two slow earthflows in structurally complex clayey formations of the Italian southern Apennines, this paper shows the results of a long-term displacement monitoring using integrated systems of inclinometers and GPS, and their comparison with PSInSAR data. A fixed-in-place and traversal inclinometer system, first installed in 2004, recorded both the shear displacements along the slip bands, and the internal deformations of the landslide masses. A GPS network of permanent stations and benchmarks, installed in 2006&ndash, 2007 in 23 strategic points of the slope, allowed for the temporal continuity of displacement monitoring. The two long series of data allowed to evaluate the factor scaling of the PSInSAR COSMO-SkyMed data, although the component of the displacement vector along the line of sight (LOS) was small. PSInSAR data allowed for the monitoring extension to houses and rigid structures that acted as reflectors. The joint data analysis allowed for the comprehension of the main features of the landslides&rsquo, kinematics.

The safety of road embankments is mainly assessed in the engineering practice by limit equilibrium analyses. Locating the critical slip surface of embankments and calculating the corresponding factor of safety is a crucial task. In this paper, the continuous ant colony optimisation algorithm is used to analyse the stability of slopes with non-circular slip surfaces. To illustrate the proposed procedure, one example from published literature and another engineering case study of a landslide at a road construction site in India is analysed. This latter study is supplemented by the results of geotechnical investigations performed before and after the failure of the embankment. The results demonstrate that the proposed technique identifies correctly the critical slip surface and can thus be used for engineering applications.

The slow and continuous movements of a deep and complex active landslide system cause severe damage to Latronico, a village of the Italian southern Apennines. In order to obtain a deeper insight in the phenomenon, its kinematic features have been investigated by means of both ground based displacement measurements (by mobile and fixed-in-place inclinometers) and by the processing of images acquired by synthetic aperture radar sensors (ERS, Envisat, COSMO-SkyMed satellites). The results of the analyses show that the landslide system includes different phenomena at different scales and of different age, from old and huge landslides (early stage of last post-glacial) to young shallower reactivations. Secondary creep and rain-induced displacements coexist, occurring at different depths. The reconstruction of the kinematic history of the inhabited area–subsoil system shows that the yearly average displacement rates have been almost constant over the last 25 years (several cm/year). The depth of the slip surfaces and the volumes of the instable soils explain why the numerous and expensive remedial measures and stabilization interventions have had very limited effects, if any, on the displacement rate field.

Rainfall is among the most relevant triggering factors of landslides. With the aim of defining a model of the influence of rainfall on deep landslides, this paper presents data of a long-term monitoring of pore water pressures in a clayey earthflow, and the results of many field permeability tests carried out with several procedures. Pore water pressures are being monitored in the Costa della Gaveta slope since 2005. In the last years, new instruments have been installed and permeability tests have been carried out in the stable formation, in the landslide body and in the slip zone. The hydraulic conductivities of the three different zones of the subsoil have been evaluated by two types of field tests: falling head tests (by Casagrande piezometers and test wells), and localized constant head tests (by a permeameter ad hoc designed). The experimental data show that: a) pore water pressures along the slip zone respond to rain more than in the landslide body and in the stable formation, even at about 25 m depth; b) the hydraulic conductivity ksz of the slip zone is much higher than that of the landslide body, kl, in turn higher than the hydraulic conductivity of the stable formation, kf. The numerical 3D modelling of steady-state reference conditions and of transient processes caused by the historical rainfall series shows that the occurrence of ksz higher than kl and kf determines an overall drainage effect which makes the global limit equilibrium safety factor SF greater than that evaluable for other possible conditions. On the other side, even the lowest measured hydraulic conductivity ksz provides seasonal rain effects on water pressures along the slip surface such to determine significant SF variations in phase with the observed seasonal displacement rates.

Background & Aims: Helicobacter pylori (H. pylori) eradication in patients who failed one or more therapeutic attempts remains challenging. This study aimed to assess the efficacy of three-in-one capsules bismuth-based quadruple therapy (Pylera®) in these patients managed in clinical practice. Methods: This was a prospective, open-label, multicenter study enrolling consecutive, adult patients with persistent H. pylori infection following at least one standard therapy. All patients received a rescue quadruple therapy with Pylera (3 capsules four times daily) and esomeprazole 20 mg (1 tablet twice daily) for 10 days. H. pylori eradication was assessed by using Urea Breath Test 4-6 weeks following therapy ending. H. pylori eradication rates, compliance, and side-effects were calculated. Results: A total of 208 patients in the 9 participating centres were enrolled. Overall, 180 patients were successfully cured from the infection, accounting for 86.5% (95% CI 81.9-91.2) and 92.3% (95% CI 88.6-96.1) eradication rates at intention-to-treat analysis and at per protocol analysis, respectively. Cure rates were similar across patients who failed one to three previous therapy attempts, but the success rate fell to 67% after 4 or more therapy failures. Compliance to therapy was good in 198 (95.2%) patients, whilst in 7 (5.3%) cases the therapy was interrupted within 5 days due to side effects. A total of 97 (46.6%) patients complained of at least one side effect; nausea, diarrhea and vomiting were the most frequently reported. Conclusions: Our study found that this bismuth-based quadruple therapy is highly effective as second-line and rescue therapy for H. pylori eradication in clinical practice. Abbreviations: CI: confidence intervals; ITT: intention-to-treat; PP: per protocol; UBT: urea breath test.

X-Band systems provide Very High Resolution (VHR) SAR data that have important applications in several areas of the risk monitoring. Processing of interferometric VHR SAR data stacks allows the accurate monitoring of deformation affecting buildings. In this work we discuss the application to the monitoring of the Latronico town, a village in South Italy, severely affected by the slow and continuous movement of a landslide. Data are relevant to the COSMO-SkyMed constellation and results are generated via a tomographic processing.

Like many villages of the Italian Apennines, Latronico is constructed on a huge landslide system which causes severe damage to the entire inhabited zone. Continuous reinforcement works, and even demolition and reconstruction of the most damaged structures are continuously being performed, with high social and private costs. This paper presents the results of a long-term monitoring of the displacements carried out by in situ (mobile and fixed-in-place inclinometers and theodolite) and remote sensors (ERS, ENVISAT, COSMO-SkyMed satellites) showing that the landslide system has been moving over the last 25 years with almost constant average yearly rates. The movements in correspondence of the inhabited area occur with rates of several cm/yr along a system of shallow and deep slip surfaces in the range 20 m-40 m depth. The stabilization interventions (shallow and deep drainage, retaining works, reshaping) have had in practice no effects on the general kinematics over the monitoring time. The analysis of the displacement field allows: (a) the localization of the zones of largest deformations and greatest risk for the inhabited area, (b) the identification of the most active triggers and (c) the evaluation of the effects on the displacement rate of the main remedial works.

Diverticular disease (DD) is an umbrella definition that includes different clinical conditions ranging from diverticulosis to severe and potentially life-threatening complications. In the last decade, new concepts regarding pathogenetic alterations have been developed, while the diagnostic, clinical and therapeutic approaches to the management of DD patients have changed. The protective role of dietary factors (i.e., fiber) has been questioned, whilst some drugs widely used in clinical practice have been found to have a deleterious effect. The use of antibiotics in all patients with acute uncomplicated diverticulitis was reconsidered, as well as the need for a surgical approach in these patients. Conflicting recommendations in different guidelines were proposed for the treatment of symptomatic uncomplicated DD. An endoscopic classification of DD was introduced, and a “curative” endoscopic approach has been pioneered. Based on these observations, which together amount to a kind of “Copernican revolution” in the management of DD patients, we performed a comprehensive and critical reappraisal of the proposed modifications, aiming to discriminate between certainties and doubts on this issue.

Objective Postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS) are the two main forms of functional dyspepsia (FD). Probiotics are a promising therapy for FD, but current data remains heterogeneous. This work aims to evaluate a probiotic combination of Lacticaseibacillus rhamnosus LR04 (DSM 16605), Lactiplantibacillus pentosus LPS01 (DSM 21980), Lactiplantibacillus plantarum LP01 (LMG P-21021), and Lactobacillus delbrueckii subsp. delbruekii LDD01 (DMS 22106), alone or together with other pharmacological therapies, for clinical improvement of symptoms associated with FD. Methods Patients with FD were enrolled and divided into two groups: PDS and EPS. Probiotic alone or combined with prokinetics, antacids, or proton-pump-inhibitors were administered for 30 days. A progressive-score scale was used to evaluate symptoms in all patients at the beginning of the trial and at 15 days after the end of treatment. Results A cohort of 2676 patients were enrolled (1 357 with PDS; 1 319 with EPS). All patients showed significant improvements in dyspeptic symptoms following treatment. In patients with PDS, probiotic alone resulted in the lowest prevalence of symptoms following treatment, while patients with EPS showed no clear between-treatment differences. Conclusions Dyspeptic symptoms were reduced following treatment in all patients.

The Varco d’Izzo landslide system (Basilicata Region, Italy) develops at the suburbs of the city of Potenza, capital of the region, and is crossed by two transport infrastructures of local importance: the national highway Basentana and the national railway line. This paper is focused on the effects of slope movements on the railway tunnel which was built in the accumulation of an earthflow of the landslide system. The earthflow displacements were slow but continuous in the monitoring period 2005-2015 and in the order of one to several cm/year. They have led, not far from the railway tunnel area, to the eviction of a house, the dismantling of a pedestrian bridge, damages to roads and other structures. The tunnel was completely re-built in 1992 between two rows of piles, by the cut-and-cover method, after the previous tunnel had suffered severe damage due to the landslide. Available inclinometer data seem to suggest that, locally, the tunnel with its piles is hindering landslide displacements. In fact, measurements carried out in the vicinity of the tunnel, upslope from it, do not show a slip surface crossing the piles. On the other hand, landslide displacements are observed both farther, upslope from the tunnel, and downslope from it. The resultant of earth pressures acting on the tunnel is thus, probably, increasing with time. The distribution of landslide displacements around the tunnel until recent years is herein analyzed. Results of site surveys are reported. The causes of the current state of deformation of the tunnel, which was evaluated by laserscanning, are examined with the help of simplified calculations and FEM simulations.

Soil deterioration can be an important cause of earthflow activity. Current studies try to provide a deeper understanding of the processes that influence soil deterioration and of the processes that, on the contrary, can improve soil mechanical properties. This paper points out the role of the composition of pore fluid. In the Costa della Gaveta slope, this is an aqueous ion solution, with concentration increasing with depth to values typical of seawater. Na + is the prevailing cation, a reduction of its concentration causes dramatic decrease in strength. On the other side, the laboratory results show that exposure of the soil to KCl solutions, inducing an increase in pore K + concentration, makes shear strength increase greatly and permanently. First results of chemical treatment by KCl columns at Costa della Gaveta show that ion transport is faster than hypothesized on the basis of in situ falling head permeability tests, probably because of preferential flow patterns along the slip surface and other discontinuities.

This work reports on the application of a distributed fiber-optic strain sensor for long-term monitoring of a railway tunnel affected by an active earthflow. The sensor has been applied to detect the strain distribution along an optical fiber attached along the two walls of the tunnel. The experimental results, relative to a two-year monitoring campaign, demonstrate that the sensor is able to detect localized strains, identify their location along the tunnel walls, and follow their temporal evolution.

Seven teams took part in a benchmarldng exercise on selection of parameter values for the Barcelona Basic Model (BBM) from experimental data on an unsaturated soil. All teams were provided with experimental results from 9 tests performed on a compacted soil in order to determine values for the ten BBM soil constants and an initial value for the hardening parameter. The coordinating team then performed simulations (at stress point level) with the 7 different sets of parameter values, in order to explore the implications of the differences in parameter values and hence to investigate the robustness of existing BBM parameter value selection procedures. The major challenge was found to be selection of values for the constants lambda(0), r, beta, N(0) and p(c) and an initial value for the hardening parameter (p) over bar (0)(0), with the various teams proposing significantly different values for some of these key parameters. A key lesson emerging from the exercise is the importance of choosing a method for selecting values for the parameters beta and p(c) which places the main emphasis on attempting to optimise the match to the experimental spacing of normal compression lines at different values of suction. (C) 2015 Elsevier B.V. All rights reserved.

Active landslides in clay shales are widespread in Mediterranean countries. One of their characteristics is that the mobilized shear strength corresponds to the residual strength. The residual friction angle of clays depends on pore fluid composition which, in formations of marine origin, could have changed after emersion from the sea because of a number of processes, e.g., contact with rain or fresh water. This study aims at evaluating the influence of pore fluid composition and of its changes on the behaviour of Costa della Gaveta landslide, used as a case study. The natural pore fluid composition was analysed; then, the influence of such composition on the residual strength, and the effects of its variation on the shear creep behaviour were investigated. The paper shows that the natural pore fluid is a composite salt solution with variable concentration. It exhibits characteristics close to those of seawater at about 30 m depth, whereas it is very dilute close to the ground surface. Salt solutions at various concentrations and distilled water were thus used to simulate in the laboratory tests the effects of the different natural pore solutions. The results show that the residual friction angle varies significantly within the field concentration range. Moreover, exposure to distilled water causes a noticeable decrease in the residual strength during tests under constant shear displacement rate. Consistently, under constant driving shear stresses, time dependent displacements are observed, evolving with primary, secondary and tertiary creep phases, characterized, respectively, by decreasing, constant and increasing displacement rates.

This paper analyzes the effects of a historical rain series on pore water pressure distribution in the Costa della Gaveta landslide, in the Southern Apennine, Italy. The effects of pore water pressure variations on the safety factor and on the displacement rate of the landslide are also analysed. The aim of the investigation is to reach a deeper understanding of the influence of hydrological parameters on the mechanism of movements of the widespread type of active, very slow landslides in fine-grained soils. Pore water pressures were evaluated by means of the 3D finite difference code MODFLOW, applying as boundary condition the long historical rainfall series of the site. The transient analysis carried out with a daily resolution successfully reproduces the trend of piezometric data. The results show that because of the subsoil low permeability (k = 10−8–10−9 m/s), pore water pressure variations caused by rain are significant only at depths lower than about 10 m. Furthermore, noticeable depth-depending time lag is evaluated between the external hydrological input and responses of internal pore water pressures. Pore water pressure variations on the shallowest areas of the slip surface have the greatest influence on the 3D limit equilibrium safety factor and thus on the landslide movements. As a matter of fact, the safety factor seems to be well correlated to the displacement rates evaluated by inclinometers at various depths, on the slip surface. The results of the 3D model provide pore water pressure distributions which are significantly different, both in value and in time trend, from those obtained by using 2D models.

Deep and superficial displacements have been measured since 2005 in a slow active landslide that has occurred in a stiff clay formation of the Italian Southern Apennines. Recently, new inclinometer casings have been installed to achieve further information on the displacement field. In this paper, standard inclinometer profiles and fixed-in-place probe data are analysed over time. New data confirm previous hypotheses on geometry and kinematics and add more information on the viscous component of displacements. The mechanism of movement, in most of the track, essentially corresponds to sliding localized on a shear surface, consistently with stress and strength distribution. However, locally, internal viscous deformations also occur, especially in the weathered and softened zones of the landslide, and contribute to the soil discharge continuity. Viscous displacements can be interpreted by a simplified rheological model based on the Bingham equation. The residual shear strength has been considered as the creep threshold value and the dynamic viscosity has been considered dependent on the stress level, on the basis of long term direct shear tests under controlled shear stresses which were carried out in laboratory.

Inclinometer and piezometer measurements have been carried out since 2005 in a slow active earthflow in a clay shale formation of the Italian Southern Apennines. Previous studies outlined the main geometrical and kinematic features of the landslide and the pore pressure response to rainfall. Displacement rates seem to depend on the hydrological conditions as suggested by their seasonal variations. The availability of long time series of data, in some periods recorded in continuum, allows the use of a data mining approach to evaluate the relations among displacement rates in different points of the landslide, and between displacement rates and rainfall. To define such relations, the evolutionary modelling technique EPRMOGA, based on a genetic algorithm, has been used in this paper. The results give a deeper insight into the landslide behaviour on the one hand and, on the other hand, show the reliability of the technique, also in building up management scenarios. In particular, the results show that the landslide displacement rates in different points of the slip surface, although characterized by different values, are linearly dependent and thus have the same time trend, supporting the hypothesis of a constant soil discharge mechanism of movement. Piezometric data in single points cannot be used, in the considered case, to forecast displacements. The obtained relations allow to quantify the displacement rate variations due to contemporary rainfall. The influence of past rainfall is shown to decrease exponentially with temporal distance. Furthermore, the EPRMOGA simulations seem to confirm that there are no other dominant causes, besides rainfall, responsible of displacement rate variations in time.

This paper describes the geometrical structure and the main kinematic features of an ancient and active landslide which develops in structurally complex formations of the Southern Apennines (Italy): a scaly clayey formation in the medium and lower part of the slope, and a stratified marly–calcareous rock formation in the upper part. The landslide 3D geometry was reconstructed by using topographic data, stratigraphies from continuous coring boreholes and inclinometer data. The analysis of the kinematic features was based on the measurement of deep and superficial displacements. Laboratory tests were carried out to evaluate shear strength parameters. It was found that in each investigated transversal section of the landslide channel the displacements can be considered uniform, and that the decrease of the displacement rates, from upslope to downslope, mostly depends on the increase in the areas of transversal sections, the “soil discharge” variations being slight. Stability analyses confirmed that shear strength close to the residual value is available on the slip surface. The large difference between residual strength and peak strength of the landslide material is consistent with the displacement uniformity.

This paper reports experimental data on surface and deep displacements evaluated by means of GPS stations and inclinometers in two rototranslational deep landslides in a clayey slope of the Italian Southern Apennines. The displacements of the landslides cause continuous damage to buildings and infrastructures. To study these phenomena and control their effects, the local public administration provided financial support for a geotechnical investigation that started in 2004. Laboratory tests, in situ pore pressure and inclinometer measurements were carried out. In July 2006, systems of fixed-in-place inclinometer probes with continuous data acquisition were installed in two of the eleven guide casings, in correspondence to the slip surfaces detected by previous periodical measurements. In the meanwhile, a GPS network was installed, consisting in six permanent stations and ten non-permanent ones. Among the latter, five were installed on the top of five inclinometer casings. The experimental results show that, in the case under study, the surface displacements evaluated by means of the GPS stations are consistent with the surface displacements evaluated by means of the inclinometer measurements. This implies mutual data validation, availability of considerable amount of continuous data, as well as monitoring continuity when, for some reason, one of the instruments goes out of use.

Slope stability is influenced by many factors, among which are subsoil structure and pore water pressure distribution. This paper presents a multi-disciplinary approach for the determination of these two factors and for the construction of a reliable model of the subsoil for the slope stability analysis. The case of a clay slope located in the Southern Apennines ( Italy) is presented and discussed. Geophysical imaging (2D electrical resistivity tomography-ERT), in situ geotechnical monitoring ( measurements of pore pressures and horizontal displacements) and laboratory geotechnical tests ( for the determination of index, hydraulic and mechanical properties of soils) have been carried out. The comparison and the integration between ERT images and direct observations of the material extracted from boreholes have allowed us to reconstruct the subsoil stratigraphy with continuity. Thus, a reliable 2D model of the subsoil has been obtained, with well-defined boundaries on which it has been possible to apply appropriate hydraulic conditions. This geotechnical model has been used for studying the pore water pressure distribution and for analysing how the hydraulic boundary conditions-among which rain events - influence the slope stability. Our findings demonstrate the powerful skill of the ERT, if integrated with borehole data, to generate an accurate subsoil model. It is also evident that geophysical imaging can be a source of ambiguity and misjudgement if interpreted without a comparison with geotechnical data.

This is the follow-up paper to Vassallo et al. (2007), which discussed the experimentally observed small-strain behaviour of an unsaturated compacted silt. The influence that suction and, more in general, mean net stress – suction history has on the initial shear stiffness was analysed and ascribed to the accumulation of irreversible volumetric strains. In this study, a model able to predict the observed behaviour is proposed, based on classical unsaturated soil volumetric hardening elastoplastic formulations. Starting from the interpretation of the results relative to simple stress paths, such as preliminary equalization and loading–unloading compression, the results of "complex" stress paths, such as those including drying–wetting cycles, have subsequently been modelled by introducing some additional parameters.Key words: unsaturated, compacted, small strain, stiffness, volumetric behaviour, stress history.

This paper is focused on pore pressure response to rainfall in a clayey, deep seated landslide of the Southern Italian Apennines. The displacements of the studied landslide, measured by several techniques, including fixed-in-place inclinometer probes with continuous acquisition, are very slow and show seasonal rate variations of about an order of magnitude. The relationship between such variations, pore pressure changes and rainfall history was investigated. A finite difference code was used in 2D and 3D conditions, carrying out transient analyses with the historical rainfall of the site as boundary condition. We analyzed how the pore pressure time trend and distribution along the slip surface, whose depth varies significantly in the three dimensions, can influence the safety factor. The comparison between calculated and measured pore pressure time trends reveals that the best agreement and a clearer picture of the global response of the landslide are achieved by using a daily discretization.