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In volcanology, 2D morphometric analysis is a method often applied for quantitative characterization of eruptive products, used to compare tephra from different events or phases, infer eruptive styles and underlying clast generating mechanisms, or describe the aerodynamic behavior of tephra. Such particle shape analyses can be conducted using particle silhouettes or cross-sectional slices, obtained under by means of electron or optical microscope imagery. Over the course of the last years, a number of different morphometric systems have been used. Each of them uses its own nomenclature and mathematical definitions of shape-describing parameters, some of which can only be obtained using specific commercial software. With the PARTIcal Shape ANalyzer PARTISAN we present a freeware tool which parameterizes 2D shapes and provides a suite of shape descriptors, following the respective standards of the five most commonly used 2D morphometric systems. Use of PARTISAN will enable the user to study and archive the results of particle shape analysis in a format compatible with various published routines, thus increasing the potential for linking new work with results of work previously published by other groups. It will allow as well the cross-comparison of results obtained by these morphological routines. PARTISAN hence could be seen as a “Rosetta Stone” for volcanological particle morphometry, and opens the way towards an inter-group effort for a standardized 2D description of particle shapes.

The alluvial plain of the Ceyhan River (SE Turkey) has been populated since the Neolithic. In 1954, Marjory Veronica Seton-Williams described for this area several archeological mounds (höyük), which are the remains of ancient settlements. Today, according to the archeological research carried out in the area, some of these mounds result to have been leveled by agricultural activities. In this work, we identified many color anomalies by low-cost remote-sensing analyses of satellite images. We checked the nature of these anomalies in a dedicated survey and we found a good correspondence between color anomalies and archeological remains consistent with leveled höyük. We compared the grain size and chemical characteristics of the soil collected inside the color anomalies with the soil collected in other areas of the alluvial plain. We found irrelevant differences in grain-size characteristics, but a higher content of CaCO3 in soils collected inside the anomalies with respect to those collected outside. Therefore, the content of CaCO3 could be considered the feature that makes the color anomalies visible. The reason for this higher content of CaCO3 is related to the anthropogenic material used in the different phases of höyük growth. This work suggests a low-cost analysis useful for rapid identification and preservation of archeological information on the history of Mediterranean settlement.

This paper presents PYFLOW_2.0, a hazard tool for the calculation of the impact parameters of dilute pyroclastic density currents (DPDCs). DPDCs represent the dilute turbulent type of gravity flows that occur during explosive volcanic eruptions; their hazard is the result of their mobility and the capability to laterally impact buildings and infrastructures and to transport variable amounts of volcanic ash along the path. Starting from data coming from the analysis of deposits formed by DPDCs, PYFLOW_2.0 calculates the flow properties (e.g., velocity, bulk density, thickness) and impact parameters (dynamic pressure, deposition time) at the location of the sampled outcrop. Given the inherent uncertainties related to sampling, laboratory analyses, and modeling assumptions, the program provides ranges of variations and probability density functions of the impact parameters rather than single specific values; from these functions, the user can interrogate the program to obtain the value of the computed impact parameter at any specified exceedance probability. In this paper, the sedimentological models implemented in PYFLOW_2.0 are presented, program functionalities are briefly introduced, and two application examples are discussed so as to show the capabilities of the software in quantifying the impact of the analyzed DPDCs in terms of dynamic pressure, volcanic ash concentration, and residence time in the atmosphere. The software and user’s manual are made available as a downloadable electronic supplement.

1.X-Ray computed microtomography is a non-destructive 3D imaging technique that can be used for the investigation of both the morphology and internal structures of a solid object. Thanks to its versatility, it is currently of common use in many research fields and applications, from medical science to geosciences. The latter include volcanology, where this analytical technique is becoming increasingly popular, in particular for quantifying the shape as well as the internal structure of particles constituting tephra deposits. Particle morphology plays a major role in controlling the mobility of pyroclastic material in the atmosphere and particle-laden flows, while the internal structure (e.g. vesicles and crystal content) is of importance for constraining the processes occurring in magmatic chamber or volcanic conduits. In this paper, we present results of X-Ray microtomography morphological and textural analyses on volcanic particles carried out to study how particle shape is influenced by their internal structures. Particles were selected from tephra generated during explosive eruptions of different magnitude and composition. Results show how particle morphology is strongly influenced by their internal structure, which is characterized by textural features like vesicularity, vesicle and solid structure distribution, vesicles inter-connection and distance between adjacent vesicles. These have been found to vary with magma composition, vesiculation and crystallization history. Furthermore, our results confirm that X-Ray microtomography is a powerful tool for investigating shape and internal structure of particles. It both allows us to characterize the particle shape by means of tridimensional shape parameters and to relate them to their internal structures.

Summary A prospective study was designed to investigate the effects of recombinant human follicle-stimulating hormone (rhFSH) on seminal anti-Mullerian hormone (AMH) levels in men with idiopathic oligoasthenoteratozoospermia (iOAT), researching possible relationships between the seminal AMH behavior and the response to the treatment. Thirty-nine men who were candidates for intracytoplasmic sperm injection (ICSI) because of iOAT were enrolled. Patients were treated on alternately days with 150 IU of rhFSH for at least 3 months before assisted reproduction cycles. Main outcome measures were seminal AMH concentrations before and after rhFSH therapy. After treatment, 16 subjects (responders) showed an improvement in their sperm count compared to baseline (7.6 ± 2.9 vs. 19.3 ± 7.7, p

Pyroclastic density currents of the recent eruptions at Campi Flegrei Caldera (CFC — Southern Italy) have been studied with the aim of assessing the potential impact of similar events in the future. Eruptions of different scales have been investigated by means of the combined use of facies architecture, laboratory analysis and physical modeling. Both in the small (Averno 2) and intermediate (Astroni) scales, facies analysis indicates that deposits result from the emplacement of pyroclastic density currents like base-surge, formed by multiple closely-timed impulses of phreatomagmatic origin. In the large-scale event (Agnano-Monte Spina), the facies architecture suggests that the currents started as concentrated flows near the vent, as originating from the collapse of a dense eruptive column, and evolved laterally into expanded flows by the propagation of the basal shear current. Laboratory analyses on samples from the main layers of deposits allowed obtaining the input data for the PYFLOW code, which was used for reconstructing the flow dynamic characteristics of the currents. The expected damage is discussed in terms of the probability density function of dynamic pressure and particle volumetric concentration. In this way, the range of potential impact that similar pyroclastic density currents could cause to buildings, infrastructures and population is defined. In the large-scale event, the dynamic pressure ranges from 9.38 to 1.00 kPa (integrating the basal 10 m of the current) at distances of 1.5 and 4.0 km from the vent, respectively. The values are highly influenced by the local topography. In the intermediate-scale event, the dynamic pressure ranges from 2.43 to 0.26 kPa at distances of 1.1 and 1.4 km from the vent, respectively. In the small scale event, the dynamic pressure ranges from 1.49 to 0.39 kPa at distances of 0.5 and 1.1 km from the vent, respectively. The particle volumetric concentration at a height of 2 m within the current is always lower than 0.01, but typically it is higher than 0.001 inside the caldera, and could have severe effects on the unsheltered population, also at locations (topographic highs) where velocity and dynamic pressures are low. In distal reaches outside the caldera the widespread fine ash originated by buoyancy from the currents, which was transported by lower atmosphere winds, is to be considered as a “fallout load” slowly accumulating on the ground surface (and building roofs) during the waning stage of the current.

The drag of non-spherical rough particles has been investigated in a wide range of Reynolds numbers (0.03–10,000). The study is based on experimental measurements of the terminal velocities of irregular particles falling in fluids of different densities and viscosities. The particle shape is described by a shape factor that takes into account both sphericity and circularity, which are measured via image particle analysis techniques. This shape factor is particularly suitable for non-spherical and highly irregular particles. The drag coefficient has been correlated to the particle Reynolds number and the shape factor and a new correlation law has been found; the correlation has the functional form of a power law. Due to the mutual dependency of the particle terminal velocity on the drag coefficient, which in turn depends on the particle shape and Reynolds number, an iterative procedure needs to be designed for calculating the terminal velocity of particles of a specific size and shape. Such a procedure is adopted herein and a spreadsheet and a Fortran 90 code allowing the iterative calculation are provided in the Supplementary Material. The fitting of experimental measurements with our model calculations show that our new law predicts the drag coefficients and the terminal velocity of irregularly shaped particles, as volcanic ash, more accurately than other shape-dependent drag laws.

New microstructural data on the mylonites from the well-exposed Palmi shear zone (southern Calabria) are presented with the aim to shed light on both the kinematics and the geometry of the southwestern branch of the Alpine belt during Eocene. In the study area, located between the Sardinia–Corsica block and the Calabria–Peloritani terrane, previous large-scale geodynamic reconstructions suggest the presence of strike–slip or transform fault zones dissecting the southwestern branch of the Alpine belt. However, there are no field data supporting the occurrence of these structures. This paper uses vorticity analysis technique based on the aspect ratio and the long axis orientation of rigid porphyroclasts in mylonitic marbles and mylonitic granitoids, to estimate the contribution of pure and simple shear of deformation during the movement of the Palmi shear zone. Porphyroclasts aspect ratio and orientation were measured on thin sections using image analysis. Estimates of the vorticity number, Wm, indicate that the Palmi shear zone recorded general shear with a contribution of pure shear of c. 65%. Then, the Palmi shear zone can be interpreted as a segment of a left-lateral transpressive bend along the southern termination of the Eocene Alpine front. Copyright © 2015 John Wiley & Sons, Ltd.

A single gem lithospheric diamond with five sulfide inclusions from the Udachnaya kimberlite (Siberia, Russia) has been analyzed non-destructively to track the growth conditions of the diamond. Sulfides are the most abundant mineral inclusions in many lithospheric diamond crystals and are the most favorable minerals to date diamond crystals by Re-Os isotope systematics. Our investigation used non-destructive, micro-Techniques, combining X-ray tomography, X-ray fluorescence, X-ray powder diffraction, and Raman spectroscopy. This approach allowed us to determine the spatial distribution of the inclusions, their chemical and mineralogical composition on the microscale, and, finally, the paragenetic association, leaving the diamond host completely unaffected. The sample was also studied by X-ray diffraction topography to characterize the structural defects of the diamond and to obtain genetic information about its growth history. The X-ray topographic images show that the sample investigated exhibits plastic deformation. One set of {111} slip lamellae, corresponding to polysynthetic twinning, affects the entire sample. Chemical data on the inclusions still trapped within the diamond show they are monosulfide solid solutions of Fe, Ni and indicate a peridotitic paragenesis. Micro-X-ray diffraction reveals that the inclusions mainly consist of a polycrystalline aggregate of pentlandite and pyrrothite. A thorough analysis of the Raman data suggests the presence of a further Fe, Ni sulfide, never reported so far in diamonds: mackinawite. The total absence of any oxides in the sulfide assemblage clearly indicates that mackinawite is not simply a "late" alteration of pyrrhotite and pentlandite due to secondary oxidizing fluids entering diamond fractures after the diamond transport to the surface. Instead, it is likely formed as a low-Temperature phase that grew in a closed system within the diamond host. It is possible that mackinawite is a more common phase in sulfide assemblages within diamond crystals than has previously been presumed, and that the percentage of mackinawite within a given sulfide assemblage could vary from diamond to diamond and from locality to locality.

A new shape-dependent fluid–particle drag law has been added into the open source fluid dynamic software MFIX-DEM (MFIX-Discrete Element Method), which is the Eulerian–Lagrangian version of the classic MFIX Eulerian–Eulerian multiphase flow model. The drag law had been obtained by previous settling experiments of volcanic pumices in a motionless Newtonian liquid (water or alcohol). Pumices are characterized by a highly irregular shape, which is much different from a sphere and drastically influences fluid drag. The new drag law defines the particle–fluid drag coefficient as a function of both the fluid regime and particle characteristics, of which the shape factor is a compact descriptor that quantifies how the particle shape differs from a simple sphere. As a validation of the integration of the new drag law in the simulation software MFIX-DEM, the code has been used to replicate the experiment results. The comparison with simulations performed with other formulas demonstrates that, by means of the new drag law, a significant improvement in the capability of the MFIX-DEM code to predict the terminal velocities of irregularly shaped particles is obtained. Thanks to this implementation, MFIX-DEM should be used, from now on, for simulating fluid–particle flows in which the particles are significantly different from simple spheres, as is usually the case of environmental flows like explosive eruptions or ash and pollutant dispersal. Based on the results of this research, in the future an improved version of MFIX-DEM will be also presented, with a drag law useful also in the case of mixtures to be treated with a Eulerian–Eulerian multiphase model.

Texto completo del documento The initial eruptive episodes of explosive eruptions are classified as phreatic if the amount of juvenile material (scoria, glass, pumice) is null, and the amount of fresh accidental lithics, and hydrothermally altered lithics, is substantial. Phreatic eruptions have been in some cases recognized as precursory events preceding phreatomagmatic and magmatic eruptive phases. Usually, the lithological features of tephra deposits are investigated and sampled in the field. Investigation of ash samples under binocular microscope or by Back-Scattered Electron (BSE) microscope images of polished sections is usually considered sufficient to typify the fragmentation mechanism of the eruption. The opening eruptive phases at Turrialba volcano, together with the formation of newintracraters (i.e. 2010, 2012, 2014) and the enlargement of theWestern Crater (29 October 2014 to present), were classified, in previous papers and internal reports as phreatic. We studied a series of ash samples erupted from 2010 to 2016, with the aim of understanding the fragmentation processes characterizing the vent opening phases.We used SEM+EDS analyses, in addition to field and microscopic investigation. Results showed a composition of accidental lithics of fresh to hydrothermally altered clasts and secondary minerals (82–98%), besides juvenile andesite fragments (2–18%), which leads us to revisit the classification of the initial eruptive phases of Turrialba as phreatomagmatic. Our method allowed the detection of a juvenile component directly involved in an effective magma-water interaction, which was possible only by a scrutinous examination of the glass surface textures by SEM in the range size between 3 and 3.5 phi. We recommend such a type of investigation when the identification of fresh magma in a new eruption is crucial for the preparedness and hazard evaluation at active volcanoes. Los episodios eruptivos iniciales de erupciones explosivas se clasifican como freáticos si la cantidad de material juvenil (escoria, vidrio, piedra pómez) es nula, y la cantidad de líticos accidentales frescos y líticos alterados hidrotermalmente es sustancial. Las erupciones freáticas se han reconocido en algunos casos como eventos precursores que preceden Fases eruptiva freatomagmática y magmática. Por lo general, las características litológicas de los depósitos de tefra se investigan y se muestrean en el campo. Investigación de muestras de cenizas bajo microscopio binocular o por retrodispersión Las imágenes de microscopio electrónico (EEB) de secciones pulidas generalmente se consideran suficientes para tipificar la fragmentación mecanismo de la erupción. Las fases eruptivas de apertura en el volcán Turrialba, junto con la formación de nuevos intracráteres (es decir, 2010, 2012, 2014) y la ampliación del cráter occidental (29 de octubre de 2014 hasta el presente), fueron clasificados, en trabajos anteriores e informes internos, como freáticos. Estudiamos una serie de muestras de cenizas erupcionadas de 2010 a 2016, con el objetivo de comprender los procesos de fragmentación que caracterizan la apertura del respiradero etapas. Utilizamos análisis SEM + EDS, además de investigación de campo y microscópica. Los resultados mostraron una composición de líticos accidentales de clastos frescos a alterados hidrotermalmente y minerales secundarios (82-98%), además de fragmentos juveniles de andesita (2-18%), lo que nos lleva a revisar la clasificación de las fases eruptivas iniciales de Turrialba como freatomagmático. Nuestro método permitió la detección de un componente juvenil directamente involucrado en una interacción eficaz entre el magma y el agua, que solo fue posible mediante un examen minucioso de la superficie del vidrio texturas por SEM en el rango de tamaño entre 3 y 3,5 phi. Recomendamos este tipo de investigación cuando el La identificación de magma fresco en una nueva erupción es crucial para la preparación y la evaluación de peligros en volcanes en estado activo. Universidad Nacional, Costa Rica Observatorio Vulcanológico y Sismológico de Costa Rica

Implantation failure is considered as a major cause of infertility in women with recurrent pregnancy loss (RPL) and in otherwise healthy women with unexplained infertility. Preliminary data in primates suggested that relaxin (RLX) is involved in endometrial preparation for implantation. In a prospective observational study, the endometrial RLX receptor (LGR7) expression was assessed in three groups of patients with regular ovulatory cycle and normal uterine cavity: 23 with RPL (Group A), 23 with unexplained infertility undergone at least three cycles of failed in vitro fertilization (IVF) reporting good oocyte and embryo quality (Group B), 23 with proven fertility (Group C). Assessment of LGR7 expression was performed with both polymerase chain reaction (PCR) analysis and immunohistochemistry on endometrial samples obtained with hysteroscopic biopsy performed in the secretory phase of the menstrual cycle. Endometrial LGR7 was less expressed in group A and B versus C, both by PCR analysis (p = 0.024) and immunohistochemistry. The decreased expression of the endometrial RLX receptor in women with implantation failures, both in vitro fertilization failure and recurrent pregnancy loss, suggests that RLX may play a crucial role in the structural and functional changes of the endometrium during the window of implantation.

To evaluate treatment efficacy and patient acceptability of the new Radiographic Tubal Assessment Set (RTAS) (Cook Ireland Ltd., Limerick, Ireland) for selective salpingography (SSG).33 women, between 23 and 38 years old, referred to the Fertility Centre of the Department of Obstetrics, Gynecology and Reproductive Science, Second University of Naples, for sterility problems, underwent an office operative SSG with the RTAS. Of the 33 women, 12 had bilateral tubal obstruction (Group A) and 21 had unilateral tubal obstruction (Group B). Patients who did not regain tubal patency were referred for laparoscopic surgery. To verify patient acceptability, a visual analogue score (VAS 1-10) of pain was completed immediately after the procedure.From a total of 45 obstructed fallopian tubes, 34 were recanalized, giving a success rate for the procedure of 75.6% (p0.001). Nine patients with bilateral tubal obstruction (Group A) had the tubes recanalized and five obtained a spontaneous pregnancy. Sixteen patients with monolateral tubal obstruction (Group B) had the tubes recanalized and nine obtained a spontaneous pregnancy. A total of seven patients were sent for operative laparoscopy: four of them had the tubes recanalized and two obtained a spontaneous pregnancy. One patient was lost to follow-up. The evaluation of the level of pain felt during the procedure on the 10 cm VAS showed mean pelvic pain 2.9 ± 2.2, and an incidence of no discomfort±low pain significantly higher than moderate±severe pain (p0.0001).The RTAS can be considered a safe and effective tool to perform this office operative procedure for tubal recanalization, with a high acceptability for the patient. The "see and treat" approach in patients with proximal tubal obstruction (PTO) suggests for the future the use of this device under sonographic guidance, taking into account accurate patient selection.

Brittle magmatic fragmentation plays a crucial role in explosive eruptions. It represents the starting point of hazardous explosive events that can affect large areas surrounding erupting volcanoes. Knowing the initial energy released during this fragmentation process is fundamental for the understanding of the subsequent dynamics of the eruptive gas-particle mixture and consequently for the forecasting of the erupting column’s behavior. The specific kinetic energy (SKE) of the particles quantifies the initial velocity shortly after the fragmentation and is therefore a necessary variable to model the gas-particle conduit flow and eruptive column regime. In this paper, we present a new method for its determination based on fragmentation experiments and identification of the timings of energy release. The results obtained on compositions representative for basaltic and phonolitic melts show a direct dependence on magma material properties: poorly vesiculated basaltic melts from Stromboli show the highest SKE values ranging from 7.3 to 11.8 kJ/kg, while experiments with highly vesiculated samples from Stromboli and Vesuvius result in lower SKE values (3.1 to 3.8 kJ/kg). The described methodology presents a useful tool for quantitative estimation of the kinetic energy release of magmatic fragmentation processes, which can contribute to the improvement of hazard assessment.

A systematic analysis of the physical parameters that influence the aerodynamics of ash, i.e. the attitude of a particle to be transported and/or settled throughout a fluid, is presented. We investigate juvenile particles from eruptions of Somma-Vesuvius, Campi Flegrei and Vulcano (southern Italy), which encompass a wide range of particle characteristics. The analysed samples were selected from dilute pyroclastic density current (DPDC) and fall deposits, and cover an ample spectrum of magma composition and fragmentation mechanisms. Data show that particles have often highly irregular shapes, as determined by the shape factor Ψ . The more irregular is the shape the higher the drag coefficient, C d , and the lower the terminal velocity. The C d of DPDC particles is lower than that of fall particles, as due to rounding by attrition at the base of a density current. As a consequence of the irregular shape, the terminal velocity of ash (0.5 mm) can be less than half of the value that results by hypothesising a spherical shape, as it is frequently done in volcanology. In the fall deposits, for the same size fraction, the settling velocity can be different for samples extracted at different locations along the main dispersal axis, especially if the clast population shows heterogeneity of vesicularity. Particle shape becomes more irregular as grain size decreases down to 0.25 mm, whereas at finer sizes the values are almost constant. This study has important implications for how long and how far volcanic particles can be dispersed aloft; this is crucial for dispersal models quantifying risk, including for international air traffic.

The detailed analysis of stratigraphy allowed the reconstruction of the complex volcanic history of La Fossa di Vulcano. An eruptive activity mainly driven by superficial phreatomagmatic explosions emerged. A statistical analysis of the pyroclastic Successions led to the identification of dilute pyroclastic density currents (base surges) as the most recurrent events, followed by fallout of dense ballistic blocks. The scale of events is related to the amount of magma involved in each explosion. Events involving about 1 million cm 3 of magma occurred during recent eruptions. They led to the formation of hundreds of meters thick dilute pyroclastic density currents, moving down the volcano slope at velocities exceeding 50 m/s. The dispersion of density currents affected the whole Vulcano Porto area, the Vulcanello area. They also overrode the Fossa Caldera's rim, spreading over the Piano area. For the aim of hazard assessment, deposits from La Fossa Cone and La Fossa Caldera were studied in detail, to depict the eruptive scenarios at short-term and at long-term. By means of physical models that make use of deposit particle features, the impact parameters have been calculated. They are dynamic pressure and particle volumetric concentration of density currents, and impact energy of ballistic blocks. A quantitative hazard map, based on these impact parameters, is presented. It could be useful for territory planning and for the calculation of the expected damage.

New volcanological studies allow reconstruction of the eruption dynamics of the Pomici di Mercato eruption (ca 8,900 cal. yr B.P.) of Somma-Vesuvius. Three main Eruptive Phases are distinguished based on two distinct erosion surfaces that interrupt stratigraphic continuity of the deposits, indicating that time breaks occurred during the eruption. Absence of reworked volcaniclastic deposits on top of the erosion surfaces suggests that quiescent periods between eruptive phases were short perhaps lasting only days to weeks. Each of the Eruptive Phases was characterised by deposition of alternating fall and pyroclastic density current (PDC) deposits. The fallout deposits blanketed a wide area toward the east, while the more restricted PDC deposits inundated the volcano slopes. Eruptive dynamics were driven by brittle magmatic fragmentation of a phonolitic magma, which, because of its mechanical fragility, produced a significant amount of fine ash. External water did not significantly contribute either to fragmentation dynamics or to mechanical energy release during the eruption. Column heights were between 18 and 22 km, corresponding to mass discharge rates between 1.4 and 6 × 107 kg s−1. The estimated on land volume of fall deposits ranges from a minimum of 2.3 km3 to a maximum of 7.4 km3. Calculation of physical parameters of the dilute pyroclastic density currents indicates speeds of a few tens of m s−1 and densities of a few kg m−3 (average of the lowermost 10 m of the currents), resulting in dynamic pressures lower than 3 kPa. These data suggest that the potential impact of pyroclastic density currents of the Pomici di Mercato eruption was smaller than those of other Plinian and sub-Plinian eruptions of Somma-Vesuvius, especially those of 1631 AD and 472 AD (4–14 kPa), which represent reference values for the Vesuvian emergency plan. The pulsating and long-lasting behaviour of the Pomici di Mercato eruption is unique in the history of large explosive eruptions of Somma-Vesuvius. We suggest an eruptive scheme in which discrete magma batches rose from the magma chamber through a network of fractures. The injection and rise of the different magma batches was controlled by the interplay between magma chamber overpressure and local stress. The intermittent discharge of magma during a large explosive eruption is unusual for Somma-Vesuvius, as well as for other volcanoes worldwide, and yields new insights for improving our knowledge of the dynamics of explosive eruptions.

Pyroclastic flows represent the most hazardous events of explosive volcanism, one striking example being the famous historical eruption of Vesuvius that destroyed Pompeii (AD 79). Much of our knowledge of the mechanics of pyroclastic flows comes from theoretical models and numerical simulations. Valuable data are also stored in the geological record of past eruptions, including the particles contained in pyroclastic deposits, but the deposit characteristics are rarely used for quantifying the destructive potential of pyroclastic flows. By means of experiments, we validate a model that is based on data from pyroclastic deposits. The model allows the reconstruction of the current's fluid-dynamic behaviour. Model results are consistent with measured values of dynamic pressure in the experiments, and allow the quantification of the damage potential of pyroclastic flows.

Pyroclastic density currents (PDCs) generated during the Plinian eruption of the Pomici di Avellino (PdA) of Somma–Vesuvius were investigated through field and laboratory studies, which allowed the detailed reconstruction of their eruptive and transportation dynamics and the calculation of key physical parameters of the currents. PDCs were generated during all the three phases that characterised the eruption, with eruptive dynamics driven by both magmatic and phreatomagmatic fragmentation. Flows generated during phases 1 and 2 (EU1 and EU3pf, magmatic fragmentation) have small dispersal areas and affected only part of the volcano slopes. Lithofacies analysis demonstrates that the flow-boundary zones were dominated by granular-flow regimes, which sometimes show transitions to traction regimes. PDCs generated during eruptive phase 3 (EU5, phreatomagmatic fragmentation) were the most voluminous and widespread in the whole of Somma–Vesuvius’ eruptive history, and affected a wide area around the volcano with deposit thicknesses of a few centimetres up to more than 25 km from source. Lithofacies analysis shows that the flow-boundary zones of EU5 PDCs were dominated by granular flows and traction regimes. Deposits of EU5 PDC show strong lithofacies variation northwards, from proximally thick, massive to stratified beds towards dominantly alternating beds of coarse and fine ash in distal reaches. The EU5 lithofacies also show strong lateral variability in proximal areas, passing from the western and northern to the eastern and southern volcano slopes, where the deposits are stacked beds of massive, accretionary lapilli-bearing fine ash. The sedimentological model developed for the PDCs of the PdA eruption explains these strong lithofacies variations in the light of the volcano’s morphology at the time of the eruption. In particular, the EU5 PDCs survived to pass over the break in slope between the volcano sides and the surrounding volcaniclastic apron–alluvial plain, with development of new flows from the previously suspended load. Pulses were developed within individual currents, leading to stepwise deposition on both the volcano slopes and the surrounding volcaniclastic apron and alluvial plain. Physical parameters including velocity, density and concentration profile with height were calculated for a flow of the phreatomagmatic phase of the eruption by applying a sedimentological method, and the values of the dynamic pressure were derived. Some hazard considerations are summarised on the assumption that, although not very probable, similar PDCs could develop during future eruptions of Somma–Vesuvius.

The stratigraphic succession of the Pomici di Avellino Plinian eruption from Somma-Vesuvius has been studied through field and laboratory data in order to reconstruct the eruption dynamics. This eruption is particularly important in the Somma-Vesuvius eruptive history because (1) its vent was offset with respect to the present day Vesuvius cone; (2) it was characterised by a distinct opening phase; (3) breccia-like very proximal fall deposits are preserved close to the vent and (4) the pyroclastic density currents generated during the final phreatomagmatic phase are among the most widespread and voluminous in the entire history of the volcano. The stratigraphic succession is, here, divided into deposits of three main eruptive phases (opening, magmatic Plinian and phreatomagmatic), which contain five eruption units. Short-lived sustained columns occurred twice during the opening phase (Ht of 13 and 21.5 km, respectively) and dispersed thin fall deposits and small pyroclastic density currents onto the volcano slopes. The magmatic Plinian phase produced the main volume of erupted deposits, emplacing white and grey fall deposits which were dispersed to the northeast. Peak column heights reached 23 and 31 km during the withdrawal of the white and the grey magmas, respectively. Only one small pyroclastic density current was emplaced during the main Plinian phase. In contrast, the final phreatomagmatic phase was characterised by extensive generation of pyroclastic density currents, with fallout deposits very subordinate and limited to the volcano slopes. Assessed bulk erupted volumes are 21 × 106 m3 for the opening phase, 1.3–1.5 km3 for the main Plinian phase and about 1 km3 for the final phreatomagmatic phase, yielding a total volume of about 2.5 km3. Pumice fragments are porphyritic with sanidine and clinopyroxene as the main mineral phases but also contain peculiar mineral phases like scapolite, nepheline and garnet. Bulk composition varies from phonolite (white magma) to tephri-phonolite (grey magma).

A simple semi-analytical model for ash-fall deposit was applied to reconstruct the tephra deposits of the sub-Plinian 472 AD eruption of Vesuvius, Italy, which is of the scale of the reference eruptive scenario for the emergency planning, at Vesuvius. Applying a novel least-squares method, the bulk grain-size distribution, the total mass, and the eruption column height were obtained by fitting the computed ground load and granulometries with the observed ones. The analysis of the effect of three different weighting factors in the minimization procedure was also performed. Results showed that the statistical weighting factor produced the minimum bias. The best correlation between calculated and measured deposit was found, even though the quantity of the input data was not very high, as it commonly occurs for several ancient eruptions. Model results were also in agreement with estimations provided by other independent methods.

Ash samples from tephra layers correlated with the Pomici di Avellino (Avellino Pumice) eruption of Somma-Vesuvius were collected in distal archives and their composition and particle morphology investigated in order to infer their behaviour of transportation and deposition. Differences in composition and particle morphologies were recognised for ash particles belonging to the magmatic Plinian and final phreatomagmatic phases of the eruption. The ash particles were dispersed in opposite directions during the two different phases of the eruption, and these directions are also different from that of coarse-grained fallout deposits. In particular, ash generated during magmatic phase and injected in the atmosphere to form a sustained column shows a prevailing SE dispersion, while ash particles generated during the final phreatomagmatic phase and carried by pyroclastic density currents show a general NW dispersion. These opposite dispersions indicate an ash dispersal influenced by both high and low atmosphere dynamics. In particular, the magmatic ash dispersal was first driven by stratospheric wind towards NE and then the falling particles encountered a variable wind field during their settling, which produced the observed preferential SE dispersal. The wind field encountered by the rising ash clouds that accompanied the pyroclastic density currents of the final phreatomagmatic phase was different with respect to that encountered by the magmatic ash, and produced a NW dispersal. These data demonstrate how ash transportation and deposition are greatly influenced by both high and low atmosphere dynamics. In particular, fine-grained particles transported in ash clouds of small-scale pyroclastic density currents may be dispersed over distances and cover areas comparable with those injected into the stratosphere by Plinian, sustained columns. This is a point not completely addressed by present day mitigation plans in case of renewal of activity at Somma-Vesuvius, and can yield important information also for other volcanoes potentially characterised by explosive activity.

Small-scale pyroclastic density currents (PDCs) associated with the AD 472 (Pollena) eruption of Somma-Vesuvius, Italy, were generated by both magmatic and phreatomagmatic explosive fragmentation. The resulting deposits were emplaced under flow boundary conditions dominated by varying combinations of grain interaction, fluid escape and traction processes. Stratigraphic and lithofacies analysis of these PDCs offers a new perspective on the en masse versus progressive aggradation debate for PDC deposition. In particular, the analyses indicate that PDCs were density stratified with a basal underflow dominated by grain interactions. The underflows comprised trains of self-organized granular pulses of variable thickness and magnitude, depending on the overall particle concentration and fluid turbulence. A change in gradient between the upper and lower slopes of the volcano promoted deposition and the different pulses aggraded sequentially (stepwise). In this model each pulse stops en masse and the whole deposit aggrades progressively. Particle concentration, density, mean velocity, and flow height were assessed for the studied PDCs using differaent methods for massive and stratified deposits. The calculated mobility of the flows was 0·2 to 0·3, in the expected range for small-scale PDCs.

Sporadic colorectal cancer (CRC) is a major health concern worldwide. Epidemiologic evidence suggests a polygenic predisposition to CRC, but the genes responsible remain unknown. Here, we performed genome-wide scanning of male (ACI/SegHsd x Wistar-Furth)F2 (AWF2) rats to map susceptibility genes influencing the evolution of early colorectal lesions to adenocarcinoma following 1,2-dimethylhydrazine administration. Phenotypic analysis revealed higher incidence/multiplicity and lower size of adenomas in ACI/SegHsd (ACI) and (ACI/SegHsd x Wistar-Furth)F1 (AWF1) than Wistar-Furth (WF) rats and higher incidence/multiplicity of poorly differentiated adenocarcinomas in WF than ACI rats, with intermediate values in AWF1 rats. Linkage analysis of 138 AWF2 rats identified three loci on chromosomes 4, 15 and 18 in significant linkage with lesion multiplicity that were identified as rat Colon cancer resistance ( rCcr ) 1, rCcr2 and rCcr3 , respectively. Seven other loci on chromosomes 5, 6, 15, 17, 18 and 20 were in suggestive linkage with adenoma/adenocarcinoma multiplicity/surface area. Six of them were identified as rCcr4 – 9 and a locus on chromosome 5 was identified as a susceptibility locus, rCcs1 . Significant interactions between rCcr3 and rCcr6 , rCcr6 and rCcr8 and rCcr5 and rCcr9 , and four novel epistatic loci controlling multiplicity/size of colorectal lesions were discovered. Apc , located at rCcr3 , did not show functional promoter polymorphisms. However, influence of susceptibility/resistance genes on Wnt/s-catenin pathway was shown by defective s-catenin inactivation in WF but not in ACI and AWF1 rat adenocarcinomas. These data indicate that inheritance of predisposition to CRC depends on interplays of several genetic factors, and suggest a possible mechanism of polygenic control of CRC progression.

International audience; Dust storms are common in arid and semi-arid regions, e.g., the Arabian Peninsula, where undisturbed wind can either weather the rocks and transport the grains for kilometers over the landscape or even overseas, or form dunes and ripples. We used a multiphase Eulerian–Lagrangian computational fluid dynamics model to investigate the impact of dust storms in the form of density current on a 10 × 10-m building. This numerical investigation particularly applies to the suburbs of metropolis, consisting of peripheral neighborhoods of meter-scale buildings that, as suggested by our results, can strongly affect the path of the storm before impacting the Downtown. Our results of flow-building interaction on pulsating (CASE 1) versus sustained (CASE 2, reference) and long-lived (CASE 3) storm show a strong amplification of flow dynamic pressure up to a factor of about 14 in streamwise direction and a heavy grain accumulation of about 800 kg around the building. With respect to reference sustained storm, the results show a more intense pressure amplification up to about 12 for slower (CASE 4) or coarser (CASE 5) storm, but a less intense amplification up to about 3 for more dilute storm (CASE 6) in transverse direction. Maximum grain accumulation around the building is of about 4,300 kg (55 % is on building front) for coarser storm, whereas high fog in the building rear occurs for more dilute storm. These results can be useful when assessing the impact of dust storms against buildings.

The combined use of field investigation and laboratory analyses allowed the detailed stratigraphic reconstruction of the Pollena eruption (472 AD) of Somma-Vesuvius. Three main eruptive phases were recognized, related either to changes in the eruptive processes and/or to relative changes of melt composition. The eruption shows a pulsating behavior with deposition of pyroclastic fall beds and generation of dilute and dense pyroclastic density currents (PDC). The eruptive mechanisms and transportation dynamics were reconstructed for the whole eruption. Column heights were between 12 and 20 km, corresponding to mass discharge rates (MDR) of 7×106 kg/s and 3.4×107 kg/s. Eruptive dynamics were driven by magmatic fragmentation of a phono-tephritic to tephri-phonolitic magma during Phases I and II, whereas phreatomagmatic fragmentation dominated Phase III. Magma composition varies between phonolitic and tephritic-phonolitic, with melt viscosity likely not in excess of 103 Pa s. The volume of the pyroclastic fall deposits, calculated by using of proximal isopachs, is 0.44 km3. This increases to 1.38 km3 if ash volumes are extrapolated on a log thickness vs. square root area diagram using one distal isopach and column height.

International audience; Volcanic ash produced during explosive eruptions can have very severe impacts on modern technological societies. Here, we use reconstructed patterns of fine ash dispersal recorded in terrestrial and marine geological archives to assess volcanic ash hazards. The ash-dispersal maps from nine Holocene explosive eruptions of Italian volcanoes have been used to construct frequency maps of distal ash deposition over a wide area, which encompasses central and southern Italy, the Adriatic and Tyrrhenian seas and the Balkans. The maps are presented as two cumulative-thickness isopach maps, one for nine eruptions from different volcanoes and one for six eruptions from Somma-Vesuvius. These maps represent the first use of distal ash layers to construct volcanic hazard maps, and the proposed methodology is easily applicable to other volcanic areas worldwide.

The source conditions of volcanic plumes and collapsing fountains are investigated by means of large-scale experiments. In the experiments, gas-particle jets issuing from a cylindrical conduit are forced into the atmosphere at different mass flow rates. Dense jets (high particle volumetric concentration, e. g., C-0>0.01) generate collapsing fountains, whose height scales with the squared exit velocity. This is consistent with Bernoulli's equation, which is a good approximation if air entrainment is negligible. In this case, kinetic energy is transformed into potential energy without any significant loss by friction with the atmosphere. The dense collapsing fountain, on hitting the ground, generates an intense shear flow similar to a pyroclastic density current. Dilute hot jets (low particle volumetric concentration, e. g., C-03).

Italian Abstract: In seguito alla maggiore autonomia conferita alle Regioni dalla riforma costituzionale del 2001 e ai nuovi indirizzi europei provenienti dall’Agenda di Lisbona, l’attivita legislativa regionale in tema di innovazione si e intensificata, portando anche a una revisione critica degli strumenti adottati che in generale sono stati improntati a una maggiore selettivita. A livello regionale, il sistema degli interventi si caratterizza per una elevata frammentazione delle iniziative. Esse privilegiano il finanziamento della ricerca applicata e il contributo a fondo perduto. Per quanto riguarda le fonti di finanziamento, a partire dalla programmazione 2007-13 e cresciuta, anche per effetto della crisi economica, l’importanza dei fondi strutturali, che nel caso delle regioni meridionali rappresentano quasi il complesso delle risorse utilizzate. Questo lavoro presenta un indicatore sintetico, costituito da tre “sottoindicatori”, che approssimano, rispettivamente, l’input del processo innovativo, l’output innovativo e una misura quantitativa delle politiche regionali per l’innovazione.English Abstract: Following the constitutional reform of 2001, which gave increased autonomy Italian regions, and the new European guidelines from the Lisbon Agenda, there has been an upturn in regional legislative activity concerning innovation, leading to a critical review of the instruments adopted, mainly towards greater selectivity. Regional intervention tends to be highly fragmented, focusing on the funding of applied research and using grants as the preferred policy tool. In terms of sources of funds, structural funds have gained importance since the 2007-13 programming cycle, partly due to the economic crisis, and in the southern regions account for nearly all the resources devoted to fostering innovation. This paper presents a summary indicator, consisting of three "sub-indicators" approximating, respectively, the input of the innovation process, innovation output, and a quantitative measure of regional policies for innovation.

The constitutional reforms of 2001 and 2003 empowered the Italian regions to enact legislation aimed at removing barriers to effective gender equality. The laws they have adopted in this field are often fragmented � only in a few cases do they form a consistent, comprehensive framework � and the general lack of monitoring and absence of an effective sanctioning system make enforcement deficient. Policies for employment, for entrepreneurship and for work-life balance also differ widely among the regions. With the crisis, policies for female employment have generally been subsumed under the more general framework of support for disadvantaged workers, particularly with participation in the PARI and Welfare to Work programmes. Women have benefited extensively from these programmes, albeit with differences from region to region. Policies for entrepreneurship remain more female-oriented. Despite coordination between the central government and the regions, Italy remains far from the European targets for childcare provision and the North-South gap has not narrowed.

Con le riforme costituzionali del 2001 e 2003 le Regioni hanno assunto la potesta di legiferare per rimuovere gli ostacoli all’effettiva parita di genere. Le norme adottate sono spesso frammentate e solo in pochi casi costituiscono un quadro organico; inoltre la diffusa mancanza di previsioni di attivita di monitoraggio o di un efficace apparato sanzionatorio rende carenti gli strumenti di tutela introdotti. Anche le politiche per l’occupazione dipendente, per l’imprenditoria e per la conciliazione vita-lavoro sono molto variegate. Con la crisi, le prime sono state fatte rientrare, quasi ovunque, nel piu generale sostegno ai lavoratori svantaggiati, soprattutto con l’adesione ai programmi PARI e Welfare to work. Le donne ne hanno beneficiato in misura elevata anche se diversa da regione a regione. Negli interventi a favore dell’imprenditoria la connotazione femminile e rimasta piu diffusa. Tra le politiche per la conciliazione, vi e stato un maggiore sforzo coordinato Stato-Regioni per favorire la diffusione di asili nido, ma l’Italia si mantiene lontana dagli obiettivi europei e il divario Nord-Sud non si e ridotto. The constitutional reforms of 2001 and 2003 empowered the Italian regions to enact legislation aimed at removing barriers to effective gender equality. The laws they have adopted in this field are often fragmented – only in a few cases do they form a consistent, comprehensive framework – and the general lack of monitoring and absence of an effective sanctioning system make enforcement deficient. Policies for employment, for entrepreneurship and for work-life balance also differ widely among the regions. With the crisis, policies for female employment have generally been subsumed under the more general framework of support for disadvantaged workers, particularly with participation in the PARI and Welfare to Work programmes. Women have benefited extensively from these programmes, albeit with differences from region to region. Policies for entrepreneurship remain more female-oriented. Despite coordination between the central government and the regions, Italy remains far from the European targets for childcare provision and the North-South gap has not narrowed.

[1] The fragmentation process and aerodynamic behavior of ash from the Eyjafjallajokull eruption of 2010 are investigated by combining grain-size, Scanning Electron Microscopy (SEM), and quantitative particle morphology. Ash samples were collected on land in Iceland at 3–55 km distance from the volcanic vent, and represent various phases of the pulsating eruption. The grain size is fine even for deposits close to the vent, suggesting that the parent particle population at fragmentation consisted of a substantial amount of fine ash. SEM investigation reveals that ash produced during the first phase of the eruption consists of juvenile glass particles showing key features of magma-water interaction, suggesting that phreatomagmatism played a major role in the fragmentation of a vesicle-poor magma. In the last phase of the eruption, fragmentation was purely magmatic and resulted from stress-induced reaction of a microvesicular, fragile melt. The shape of ash, as determined by quantitative morphology analysis, is highly irregular, rendering the settling velocity quite low. This makes transportation by wind much easier than for other more regularly shaped particles of sedimentary origin. We conclude that the combination of magma's fine brittle fragmentation and irregular particle shape was the main factor in the extensive atmospheric circulation of ash from the mildly energetic Eyjafjallajokull eruption.

A prospective randomized controlled study was designed to evaluate the effects of recombinant human follicle-stimulating hormone (rFSH) treatment on sperm DNA fragmentation in men with idiopathic oligoasthenoteratozoospermia (iOAT). One hundred twenty-nine men with sperm count less than 10 × 10(6) spermatozoa/mL and forward motility25% were included; normal serum levels of FSH, luteinizing hormone (LH), and testosterone, and no other causes of infertility were enrolled. The patients were randomized into 2 groups: 65 men were treated on alternate days for 90 days with injections of 150 IU rFSH, and 64 subjects received nonantioxidant vitamin supplements. Main outcome measures were serum levels of FSH, LH, testosterone, and inhibin B and DNA fragmentation index (DFI) at baseline and after 90 days. No significant differences were observed between the 2 groups with regard to sperm parameters and hormone values. The DFI was similar between the 2 groups at the time of the enrollment but reduced significantly (P.05) after rFSH therapy in study group, whereas no significant variation occurred in the control group. In the subgroup of patients with high basal DFI values (15%), rFSH treatment significantly increased DFI (P.01), whereas no significant variation occurred after 90 days of vitamin supplements. We conclude that rFSH administration improves sperm DNA integrity in iOAT men with increased DFI values. The degree of sperm DFI might be useful to identify those iOAT patients in which rFSH treatment can be advantageous.

In a prospective observational study, 50 healthy patients aged 18–39 years, with regular ovulatory cycle and normal hormone levels, underwent endometrial biopsy in the proliferative and secretory phase of the menstrual cycle for semiquantitative reverse-transcription polymerase chain reaction analysis of mRNA for LGR7, the classic relaxin receptor. LGR7 is constitutively expressed in human endometrium, and an increased LGR7 immunostaining is demonstrated in the secretory phase, confirming the involvement of relaxin in the physiology of endometrium and suggesting its role in implantation.

[1] A new method for the reconstruction of the physical characteristics of dilute pyroclastic density currents is introduced. The velocity, density and particle volumetric concentration profiles of the stratified current are calculated, together with the profile of dynamic pressure, which is a useful parameter for checking resistance of buildings. The model links turbulent boundary layer shear flow theory with particle coupling to gas turbulence. The working procedure starts with the recognition in the field of the fining upward sequence of layers formed during the time integrated depositional history of an individual current. Distinct processes of particle transportation and deposition are associated with the different particle modes composing the bedset. The system of equations for the solution of the fluid-dynamic parameters is implemented in two alternative ways. The first one uses data of particles coming from both the basal coarse layer and the overlying laminated layer of the bedset. The second uses features of two distinct components of the laminated layer. A statistical test is performed for checking model results against experimental data of actual particles. Model calculations give the average solution, as well as solutions corresponding to a range of 68% of probability around the average value. The maximum solution can be considered as a safety value for impact parameters. The methodology is applied to deposits of recent eruptions of Vesuvius and Campi Flegrei in Italy, and results are discussed in terms of hazard and expected damage.

One of the objectives of the reforms and liberalization of the last 15 years in local public services was to reduce the traditional fragmentation of production. This was to be achieved through restructuring that reduced inefficiencies and made it more possible to exploit economies of scale, thereby stimulating the emergence of national “big players”. In this paper we analyze the evolution and current position of the largest operators that have emerged in the different sectors of local public services. The aim is to identify factors that have helped or hindered the growth process. Through an analysis of twelve among the largest businesses we identify four evolutionary paths. In our view the main drivers have been: a) a presence in the energy sector (mainly due to its high profitability); b) a favourable local political framework; and c) a tradition of efficient internal organization and independence of local politics.

Objective To compare the effects of GnRH–agonist/recombinant rFSH versus GnRH-antagonist/recombinant FSH stimulation on follicular fluid levels of soluble intercellular adhesion molecule (sICAM)-1 and vascular cell adhesion molecule-1 (sVCAM-1) during in vitro fertilization (IVF). Design Prospective, randomized study. Setting University hospital. Patient(s) Seventy-three women underwent IVF. Intervention(s) GnRH-agonist/rFSH or GnRH-antagonist/rFSH administration and collection of follicular fluid from 3 small (11–14 mm in diameter) and 3 large (18–21 mm in diameter) follicles on the day of oocyte retrieval. Main Outcome Measure(s) Follicular fluid levels of sICAM-1 and sVCAM-1 and intrafollicular estradiol and progesterone were also measured. Result(s) Women who underwent GnRH-agonist/rFSH showed higher concentrations of sICAM-1 in both small and large follicles were compared with patients who received GnRH-antagonist/rFSH treatment; follicular fluid levels of sVCAM-1 were similar between the 2 stimulation protocols. Content of sICAM-1 in small and large follicles positively correlated with the number of follicles of ≥15 mm and the number of oocytes that were retrieved in both study groups. Concentrations of follicular fluid sVCAM-1 and progesterone were higher in large than in small follicles and were correlated positively to each other in both follicular classes. Conclusion(s) In IVF, GnRH-agonist/rFSH is associated with higher follicular fluid levels of sICAM-1 compared with GnRH-antagonist/rFSH regimen. Intrafollicular sICAM-1 content may predict ovarian response, and sVCAM-1 appears as an indicator of the degree of follicular luteinization.

[1] Pumice particles represent the basic “ingredient” of many large explosive eruptions and form as a result of magma fragmentation inside the conduit. At the onset of eruption, fragmental pumices are expelled at high velocity from the crater by the overpressure of gas liberated on explosion. The resulting multiphase flow is forced through atmosphere by a variety of transportation mechanisms and pumices eventually decouple from the gas flow, settling down to form pyroclastic deposits. Here we propose new experimental data of terminal velocity together with a quantitative shape analysis of a wide range of pumice particles. The resulting model allows predicting the terminal velocity of pumice by means of easily measured particle characteristics, with an average error of 12%, which compares favourably with previous models.

Objective: To evaluate the effects of hormone replacement therapy (HRT) and of a short-term suspension of HRT on mammographic density. Design: Prospective clinical study. Setting: Outpatient menopausal clinic of the Second University of Naples. Patient(s): Ninety-seven healthy postmenopausal women. Intervention(s): Thirty-nine menopausal women with intact uterus (group A) were treated with continuous transdermal E 2 plus acetate nomegestrolo sequentially added, 37 women in surgical menopause (group B) were treated with transdermal E 2 continuously administered, and 21 menopausal women did not receive any medication (group C). At the entry and after 12 months, a mammography was performed without suspension of HRT (group A1: 19 women; group B1: 19 women) or after a short-term suspension (group A2: 20 women; group B2: 18 women). Main Outcome Measure(s): Mammographic density evaluated according to a quantitative method. Result(s): At the second mammography, seven patients in group A1, four patients in group B1, and one patient in both groups A2 and B2 showed an increase in mammographic density, whereas no mammographic density increase was observed in patients in group C. A statistically significant difference in the mammographic density increase was found between group A1 and group A2; no difference was found between group B1 and B2. Conclusion(s): Suspension of HRT for about 3 weeks may reverse mammographic density increase associated with its use.

Pyroclastic density currents (PDCs) are among the most amazing, complex and dangerous volcanic phenomena. They are moving mixtures of particles and gas that flow across the ground, and originate in different ways and from various sources, during explosive eruptions or gravity-driven collapse of domes. We present results from experimental work to investigate the generation of large-scale, multiphase, gravity-driven currents. The experiments described here are particularly devoted to understanding the inception and development of PDCs under impulsive injection conditions by means of the fast application of a finite stress to a finite mass of pyroclastic particles via expansion of compressed gas. We find that, in summary, PDC generation from collapse of pressure-adjusted or overpressurised pyroclastic jets critically depends on behaviour of injection into the atmosphere, which controls the collapsing mechanisms and then the physical parameters of the initiating current.