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Mud volcanoes are fluid escape structures allowing for surface venting of hydrocarbons (mostly gas but also liquid condensates and oils) and water–sediment slurries. For a better understanding of mud volcano dynamics, the characterization of the fluid dynamics within mud volcano conduits; the presence, extent, and depth of the fluid reservoirs; and the connection among aquifers, conduits, and mud reservoirs play a key role. To this aim, we performed a geoelectrical survey in the Nirano Salse Regional Nature Reserve, located at the edge of the northern Apennines (Fiorano Modenese, Italy), an area characterized by several active mud fluid vents. This study, for the first time, images the resistivity structure of the subsoil along two perpendicular cross sections down to a depth of 250 m. The electrical models show a clear difference between the northern and southern sectors of the area, where the latter hosts the main discontinuities. Shallow reservoirs, where fluid muds accumulate, are spatially associated with the main fault/fracture controlling the migration routes associated with surface venting and converge at depth towards a common clayey horizon. There is no evidence of a shallow mud caldera below the Nirano area. These findings represent a step forward in the comprehension of the Nirano Salse plumbing system and in pinpointing local site hazards, which promotes safer tourist access to the area along restricted routes. [ABSTRACT FROM AUTHOR]

Aim: The aim of the present study was to investigate quantitative histological examination of bone reconstructed with non-resorbable high-density polytetrafluoroethylene membrane (d-PTFE), left intentionally exposed in post extraction sockets grafted with anorganic bone material, and removed after four weeks, versus extraction and guided bone regeneration (GBR), performed two months later. Materials and Methods: This study was designed as a multicenter randomized controlled trial of parallel-group design. Patients were selected and consecutively treated in three centers in Italy. Patients randomly received intentionally exposed non-resorbable d-PTFE membrane (group A), or guided bone regeneration (group B), to treat post-extractive alveolar bone defects with implant-supported restorations. Outcomes were: the implant failure, any mechanical and biological complications, patient satisfaction, and qualitative and histomorphometric evaluation of the collected bone samples. Results: Eighteen patients were consecutively enrolled in the trial. Of these, six out of 18 patients were male. All the included patients were treated according to the allocated interventions, and no drop out occurred. No implant failure and no complications were experienced, and all the patients were fully satisfied with the function and aesthetic of their implant-supported restoration, without difference between groups. Morphological analysis revealed no sign of tissue reaction, such as fibrosis or necrosis. Regenerated bone was well mineralized in both groups, but it seemed more mature in group B than in group A. Three samples showed a minimal number of lymphocytes. Several blood vessels of small size occupied the medullary spaces, where the tissue resulted in more maturity, indicating the activity of the tissue in progress. The histomorphometric evaluation showed no statistically significant differences in the tissue volume fractions between the two groups of patients. Conclusions: With the limitation of the present study, buccal plate reconstruction with an intentionally exposed non-resorbable membrane is an effective and easy procedure for regenerating a resorbed buccal bone plate, reducing the need for guided bone regeneration. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate clinical and radiologic outcomes of a novel device that allows simultaneous hydraulic sinus membrane elevation, bone grafting, and implant placement. A sample of 18 consecutive participants with severe atrophy of the posterior maxilla underwent transcrestal elevation of the sinus membrane and implant placement. At the 6-month follow-up, the following parameters were assessed: implant success, any complications, marginal bone loss (MBL), threedimensional (3D) graft measurements, implant stability quotient (ISQ), and graft density. No implants failed during follow-up (10.8 ± 2.8 months; range: 7–14 months). No membrane tears or other adverse events were observed. Mean residual alveolar ridge height was 4.78 ± 0.88 mm. Six months after the procedure, the mean MBL was 0.18 mm. The mean sinus membrane elevation was 12.78 ± 2.18 mm (range: 10.7–14.23). Along the basic 3D reference planes, the dimensions of grafted bone measured around implants were as follows: axial area = 239.7 ± 57.68 mm2; sagittal area = 257.0 ± 60.83 mm2; coronal area = 143.3 ± 29.46 mm2. The mean volume of the graft was 2.38 ± 0.26 mL at baseline and 2.05 ± 0.24 mL 6 months after graft maturation (difference: 0.33 ± 0.29 mL, P = .0090). Graft density (in Hounsfield units [HU]), improved during healing from 322.0 ± 100.42 HU to 1,062.0 ± 293.7 HU; difference 740.0 ± 295.35 HU (P = .0001). The mean ISQ value was 65.5 at implant placement, and it increased to 74.1 at the 6-month examination (P = .0014). Of 18 patients, 12 experienced no pain (66.6%) and 10 experienced no swelling (55.5%). No severe pain or swelling was reported in any of the cases. The mean number of analgesic tablets consumed was 0.78 ± 0.67. Mean surgical time was 24.0 ± 4.07 minutes. The iRaise Sinus Lift System may provide a new option for minimally invasive transcrestal sinus surgery with minimal patient discomfort. A physiologic contraction of 13.9% of its original volume was experienced during healing. Long-term clinical studies are needed to confirm these preliminary results. [ABSTRACT FROM AUTHOR]

We investigate crustal seismic attenuation by the coda quality parameter ( Q c ) in the Gargano area (Southern Italy), using a recently released dataset composed of 191 small earthquakes (1.0 ≤ ML ≤ 2.8) recorded by the local OTRIONS and the Italian INGV seismic networks, over three years of seismic monitoring. Following the single back-scattering theoretical assumption, Q c was computed using different frequencies (in the range of 2–16 Hz) and different lapse times (from 10 to 40 s). The trend of Q c vs. frequency is the same as that observed in the adjacent Umbria-Marche region. Q c at 1 Hz varies between 11 and 63, indicating that the area is characterized by active tectonics, despite the absence of high-magnitude earthquakes in recent decades. The 3D mapping procedure, based on sensitivity kernels, revealed that the Gargano Promontory is characterized by very low and homogeneous Q c at low frequencies, and by high and heterogeneous Q c at high frequencies. The lateral variations of Q c at 12 Hz follow the trend of the Moho in this region and are in good agreement with other geophysical observations. [ABSTRACT FROM AUTHOR]

Background: The varicocele is the most commonly diagnosed pre-pubertal andrological condition with an incidence of 10%-15% between adolescents. The aim of this study was to evaluate the efficacy of retroperitoneoscopic varicocelectomy (RV) in two Italian centres with particular attention to post-operative testicular volume and semen analysis after 18 years of life.Materials and Methods: From 1999 to 2010, 286 adolescents underwent retroperitoneoscopic left varicocelectomy. Of these patients, 67 were evaluated by clinical examination, ultrasound and semen analysis, allowing an adequate long-term follow-up.Results: Surgery was performed at a mean age of 13 years (range 10-17) without intraoperative complications. There were two recurrences (3%), two left testis hypotrophy (3%) and four hydroceles (6%), not yet undergone surgery because asymptomatic or without tension. Currently, 44 patients accepted to perform semen analysis which showed a reduction in sperm motility in 12 cases, with associated morphological alterations in 3 and reducing number of spermatozoa in one case.Conclusions: In consideration of morphological and biomolecular spermatic alterations reported in adolescent varicocele that could interfere with cellular migration, differentiation and nutrition, it is fundamental to consider the correction of varicocele, not only for the classical indications, but also as a choice for arresting the progressive damage that inevitably acts for several years on the adolescent testis. The RV in adolescents is a safe and feasible procedure for experienced paediatric laparoscopic surgeons with early good clinical outcomes, but more studies occur to understand the real impact of adolescent varicocelectomy on testicular function. [ABSTRACT FROM AUTHOR]

We studied the conditions of crust and tube formation of a lava flow moving under the effect of gravity in a rectangular cross-section channel and assumed a power-law rheology for lava. We followed the work of Valerio et al. (2008), who studied the effect of surface cooling on the formation and accretion of the crust in the central region of the channel, assuming for lava a Newtonian rheology. According to these authors, tube formation is influenced by topography and channel morphology. In this work, we extended this study to a non-Newtonian rheology, in particular to the power-law rheology. Results indicate that a power-law rheology strongly influences the condition of crust formation but does not produce significant differences as a function of topographical or morphological variations. [ABSTRACT FROM AUTHOR]

Firebreaks are useful to reduce the extent of forest fires, however, when they are cleared down the slope, soil erosion is increased and the native tall sward in summer can increase fire risk. The sown mixture Trifolium brachycalycinum (Katznl. & Morley) and Cynodon dactylon L. Pers. has already proved to be useful for both fire prevention (the short sward remains green in summer, creating easy access) and biomass production (clover can give high yields with high palatability and protein levels). This pasture needs to be grazed to be kept short and reduce fuel biomass in summer. Unfortunately, there is not much livestock reared in Central Italy and animals are normally fed indoors. In this article, a trial in a coastal farm of Central Italy is reported to investigate the efficiency of horses in maintaining the sown species botanical composition, soil cover, sward height, biomass (before and after grazing) and fuel biomass in summer in a firebreak over 4 years. The mixture was intensively grazed over short periods during spring and summer. Animals grazed both the sown species and native plants, they trampled on the remaining herbage, breaking the stems, and leaving short and compact dry mulch. Very little combustible vegetation was left in the hot season and horse grazing is recommended for farms that have firebreaks. [ABSTRACT FROM AUTHOR]

The Central Apennines, Italy, are characterized by moderate seismic activity on normal faults, oriented in directions parallel to the Apenninic chain. The subject of this study is the Umbria-Marche Apennines, a segment approximately 200-km long, where three main seismic events occurred in the last three decades. The 1979 Norcia earthquake was a M w = 5.8 event, taking place at the south end of the considered segment. The 1984 Gubbio earthquake was a M w = 5.6 event which took place at the north end. The 1997-1998 Colfiorito sequence constituted 8 main shocks with magnitudes M w between 5 and 6 and epicenters located between the Gubbio and the Norcia earthquake areas. A model made of an elastic half-space is considered, in which the seismic sources are represented by rectangular dislocations which have the appropriate values of source parameters, and in which the static stress field produced by each event is calculated. The analysis of the Coulomb stress change (Δ C) as a function of time shows that the coseismic stress transfer and fault interaction played an important role in the region during the past three decades: 7 earthquakes of the 9 considered took place where Δ C>0. Such an interaction has been confirmed by the analysis of the aftershocks in the Colfiorito zone post September 26, 1997: about the 61% of the aftershocks considered took place where Δ C>0. The comparison between the Δ C s due to the coseismic stress transfer and the rate Δ Ċ t due to the tectonic stress allows us to quantify the time advance of the earthquakes. The Δ C s pattern shows positive values in two areas that can be regarded as historical seismic gaps. [ABSTRACT FROM AUTHOR]

We have provided the first estimate of scattering and intrinsic attenuation for the Gargano Promontory (Southern Italy) analyzing 190 local earthquakes with ML ranging from 1.0 to 2.8. To separate the intrinsic Q i and scattering Q s quality factors with the Wennerberg approach (1993), we have measured the direct S waves and coda quality factors ( Q β , Q c ) in the same volume of crust. Q β parameter is derived with the coda normalization method (Aki 1980) and Q c factor is derived with the coda envelope decay method (Sato 1977). We selected the coda envelope by performing an automatic picking procedure from T start = 1.5 T S up to 30 s after origin time (lapse time T L ). All the obtained quality factors clearly increase with frequency. The Q c values correspond to those recently obtained for the area. The estimated Q i are comparable to the Q c at all frequencies and range between 100 and 1000. The Q s parameter shows higher values than Q i , except for 8 Hz, where the two estimates are closer. This implies a predominance of intrinsic attenuation over the scattering attenuation. Furthermore, the similarity between Q i and Q c allows us to interpret the high Q c anomaly previously found in the northern Gargano Promontory up to a depth of 24 km, as a volume of crust characterized by very low seismic dumping produced by conversion of seismic energy into heat. Moreover, most of the earthquake foci fall in high Q i areas, indicating lower level of anelastic dumping and a brittle behavior of rocks. [ABSTRACT FROM AUTHOR]

Several regions around the globe are characterized by a seismically active lower crust, at depths where lithological and thermal conditions suggest stress release by ductile flow. The Gargano Promontory (GP, southern Italy) is an example where a recently installed seismic network has recorded an intense seismic activity at depths between 20 and 30 km, i.e. in the lower crust. The GP is located in proximity of the Gargano-Dubrovnik lineament, a seismogenic zone separating the central and southern Adriatic basins. These two basins constitute sites of sediments accumulation since Tertiary times. Another important basin in the region is represented by the Apennine foredeep, that includes the Candelaro area. We analyze the possible mechanisms controlling the distribution of seismicity in the GP to identify the factors that make the lower crust seismically active. To this aim, we construct a thermo-rheological model of a layered continental crust, calibrated on the basis of geometrical, lithological and thermal constraints. The model takes into account various crustal lithologies, the presence of fluids in the crystalline basement, lateral variations of geotherm and stress field. The numerical simulations show that the presence of fluids is a key factor controlling the cluster of seismicity in the lower crust. Moreover, the presence of water in the upper crystalline basement and sedimentary cover provides a plausible explanation for upper crustal seismicity in a zone of very high heat flow SW of the GP. The distribution of the seismicity is probably affected by the composition of the crystalline basement, with mafic bodies injected into the crust during the Paleocene magmatic phase that affected the Mediterranean region. In addition, fluid accumulation and overpressure may occur along detachment levels in the lower crust, leading to clustering of the earthquakes. Based on our findings, we hypothesize that the presence of hydrous diapiric upwelling(s) in the upper mantle can feed a deep fluid circulation system, inducing lower crustal seismicity. • A thermo-rheological model to explain lower crustal seismicity in the Gargano Promontory (Italy) is presented. • Fluid presence controls the Gargano seismic activity in the lower crust. • The Gargano crust is injected by mafic bodies at various depths. [ABSTRACT FROM AUTHOR]

Crustal seismic attenuation in the Gargano Promontory (Southern Italy) was inferred by analyzing coda waves of about one hundred small magnitude earthquakes recorded by the OTRIONS local seismic network. Coda attenuation Q c was computed using the Sato (1977) model, i.e. the assumption of single back-scattering, at different lapse times and at different frequencies. Average Q c is comparable with the same quantity measured in the adjacent area of the Umbria–Marche region (central Italy). A recent kernel-based imaging technique for Q c was then applied and the results evidence a well confined zone located South West of the investigated area, showing a sharp Q c anomaly. While Q c cannot be directly related to the physical properties of the propagation medium, its spatially-dependent modeling allows an interpretation in the light of other geophysical and geological information. Our results were then interpreted following the two extreme hypotheses according to which Q c could be representative of the effect of only intrinsic attenuation or of only scattering from the heterogeneities. Both the hypothesis correlate with the observation of anomalies in several geophysical parameters, such as heat flow, magnetic field, gravity, density, seismic velocity in the southwestern Gargano. Moreover, the Q c images support the results obtained in a recent study that shows clear variations in the rheological properties of the Gargano. The results obtained at local scale confirm and detail previous regional scale studies on attenuation and highlight for the first time the presence of a positive Q c anomaly in the south-western part of the Gargano Promontory. • Crustal seismic attenuation in the Gargano Promontory (Southern Italy) is inferred by coda waves of microearthquakes. • Coda attenuation Q c is computed under the assumption of single back-scattering, at different lapse times and frequencies. • A kernel-based technique is applied to image Q c and its uncertainties. • A sharp positive Q c anomaly in the southwestern part of the Gargano area is inferred for the first time in this study. • Q c maps suggest a rheological/lithological contrast, acting both as an elastic body and as a scatterer for seismic waves. [ABSTRACT FROM AUTHOR]