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A new image processing technique—Pyroclast Tracking Velocimetry—was used to analyze a set of 30 high-speed videos of Strombolian explosions from different vents at Stromboli (Italy) and Yasur (Vanuatu) volcanoes. The studied explosions invariably appear to result from the concatenation of up to a hundred individual pyroclast ejection pulses. All these pulses share a common evolution over time, including (1) a non-linear decrease of the pyroclast ejection velocity, (2) an increasing spread of ejection angle, and (3) an increasing size of the ejected pyroclasts. These features reflect the dynamic burst of short-lived gas pockets, in which the rupture area enlarges while pressure differential decreases. We estimated depth of pyroclast release to be approximately 1 and 8 m below the surface at Stromboli and Yasur, respectively. In addition, explosions featuring more frequent pulses also have higher average ejection velocities and larger total masses of pyroclasts. These explosions release a larger overall amount of energy stored in the pressurized gas by a combination of more frequent and stronger ejection pulses. In this context, the associated kinetic energy per explosion, ranging 103–109 J appears to be a good proxy for the explosion magnitude. Differences in the pulse-defining parameters among the different vents suggest that this general process is modulated by geometrical factors in the shallow conduit, as well as magma-specific rheology. Indeed, the more viscous melt of Yasur, compared to Stromboli, is associated with larger vents producing fewer pulses but larger pyroclasts.

A review of the existing chronological, stratigraphic and chemo-petrologic data of the major eruptive units from the early phase of activity (800–390 ka) in the Monti Sabatini Volcanic District (MSVD), belonging to the ultra-potassic magmatic region of central Italy, is presented along with new radioisotopic age determinations and geochemical analyses. Through the combined use of electron microprobe glass compositions, selected trace-element compositions, and single-crystal 40Ar/39Ar age determinations, we provide a new chrono- and chemo-stratigraphic classification of the products emplaced in the 800–390 ka time interval. Besides giving insights on the petrologic evolution of the Roman Comagmatic Region, the large dataset provides fundamental information that is applicable to tephrostratigraphic studies in the wide region encompassing the Tyrrhenian Sea margin to the Adriatic Sea basin. Distal tephras from this volcanic activity also act as important geochronologic markers for the coastal sedimentary successions deposited in response to glacio-eustatic fluctuations, as well as for successions in the Quaternary tectonic basins of the Central and Southern Apennines. An innovative approach based on the use of discrimination diagrams of Zr/Y vs Nb/Y ratios for fingerprinting altered volcanic rocks – recently developed and successfully employed in archaeometric studies – is here combined to the glass compositions for classifying the MSVD deposits and tested on two distal tephra layers, showing its potentiality for tephrostratigraphic correlation.

[1] Relationships between frequency and intensity of volcanic eruptions are actively sought by geophysicists for both monitoring and research purposes. By analyzing surveillance videos of persistent volcanic activity at Stromboli (Italy), we derived the frequency and jet height of >4000 explosions that occurred in 72 h-long time windows sampled yearly from 2005 to 2009. We found a positive relationship linking explosion frequency and jet height (linked to eruption intensity) when averaging the two parameters over time intervals from hours to days, with a stronger correlation for longer intervals. We interpret this behavior as the response of the magmatic system to variable influx of magma and gas at depth, increased flux at depth causing more frequent and stronger explosions at the surface. This relationship entails concurrent control of source processes over explosion frequency and intensity, directly impacting modeling of explosion sources at persistently active volcanoes in general and hazard assessment at Stromboli in particular.

Calderas are common on volcanoes, but their structure is seldom visible. The 19-km-wide Bolsena caldera, Italy, formed between 0.6 and 0.2 Ma. The largely preserved structural rim and subsurface data make Bolsena ideal to investigate caldera structure in relation to the subsidence and erupted volume. In this paper, we use remote sensing, field analysis, and available subsurface data. At the surface, the caldera passes from a downsag (south rim) to a narrow and densely faulted area (north rim), with outer normal and inner reverse faults. The caldera structure on the widely faulted east rim appears to be scale dependent, with a staircase-like fault zone (larger scale), horst-and-graben–like structures (intermediate scale), and domino-like structures (smaller scale). Subsurface data indicate asymmetric collapse, with a northward increase in subsidence, ranging from diffuse (to the south) to focused (to the north) deformation at the surface. The collapse rate, constant between ca. 490 and 175 ka, was more than magma output between ca. 330 and 130 ka, highlighting significant (∼200 m) and prolonged (∼200 ka) posteruptive subsidence. As the nearby Latera caldera (west rim of Bolsena) was mostly active between ca. 265 and 160 ka, much of the subsidence at Bolsena may be related to this activity, suggesting a common magmatic reservoir. The subsidence-related structural variations along the caldera rim and the significant posteruptive subsidence found at Bolsena have not been found in other calderas.

Terra Nova, 24, 233–237, 2012 Abstract The role of Earth tides as a relevant controlling factor of a variety of geological processes, including seismicity and volcanism, is widely debated. Stromboli Volcano, Italy, is well known for its persistent explosive activity and represents an ideal setting to investigate tidal effects on the energy release and eruptive behaviour of volcanoes. Herein, we report new evidence that tidal stresses may modulate the timing of eruptive activity at volcanoes in an open-vent state. We report statistically significant correlations of the peak eruption frequencies to fortnightly tidal maxima (i.e. full and new moon) during a 17-month-long period of activity in 2010–2011: in fact, the number of explosive events per hour increases by >85% during tidal maxima with respect to the average values. We suggest that tidally induced cycles of compression–decompression of country rocks controls fluctuating magma supply rate from the shallow plumbing system and, thus, eruption frequency.

Maar volcanoes represent a common volcano type which is produced by the explosive interaction of magma with external water. Here, we provide information on a number of maars in the ultrapotassic Sabatini Volcanic District (SVD, Roman Province) as young as ∼90 ka. The SVD maars are characterised in terms of crater and ejecta ring morphologies, eruptive successions and magma compositions, in light of the local substrate settings, with the aim of assessing magma–water interaction conditions, eruption energetics and genetic mechanisms. Feeder magmas spanned the whole SVD differentiation trend from trachybasalts–shoshonites to phonolites. From the ejected lithic fragments from aquifer rocks, the range of depth of magma–water explosive interaction is estimated to have been mostly at ∼400–600 m below ground level, with a single occurrence of surficial interaction in palustrine–lacustrine environment. In particular, the interaction with external water may have triggered the explosive behaviour of poorly differentiated magmas, whereas it may have acted only as a late controlling factor of the degree of fragmentation and eruption style for the most differentiated magma batches during low-flux ascent in an incipiently fragmented state. Crater sizes, ejecta volumes and ballistic data allow a reconstruction of the energy budget of SVD maar-forming eruptions. Erupted tephra volumes from either monogenetic or polygenetic maars ranged 0.004–0.07 km3 during individual maar-forming eruptions, with corresponding total magma thermal energies of 8 × 1015–4 × 1017 J. Based on energy partitioning and volume balance of erupted magmas and lithic fractions vs. crater holes, we consider the different contributions of explosive excavation of the substrate vs. subsidence in forming the SVD maar craters. Following available models based on crater sizes, highly variable fractions (5–50%) of the magma thermal energies would have been required for crater excavation. It appears that subsidence may have played a major role in some SVD maars characterised by low lithic contents, whilst substrate excavation became increasingly significant with increasing degrees of aquifer fragmentation.

This case describes the educational experiences of a foster care student named Chad. His foster parents and teacher notice educational deficits and express concern about gaps in the student’s cumulative educational record. The principal and special education director must guide all constituents to adhere to special education mandates and at the same time promote an ethical disposition toward the newly enrolled student. The case provides an opportunity for preservice and inservice administrators to analyze a situation (foster care) for which they may not have any professional or personal experiences to inform their leadership. The use of Bronstein’s theoretical model of interdisciplinary collaboration informs relevant discussion and analysis.

Generally, the intensity and magnitude of explo- sive volcanic activity increase in parallel with SiO2 content. Pyroclastic-flow-forming eruptions in the Colli Albani ultrapotassic volcanic district (Italy) represent the most striking exception on a global scale, with volumes on the order of tens of cubic kilometres and K-foiditic composi- tions (SiO2 even

The presence of young, highly explosive volcanoes in the densely populated Roman area (central Italy), makes the evaluation of the long-term volcanic hazard a crucial point. The Sabatini Volcanic District (SVD), part of the potassic Quaternary Roman Province, extends over an area of 1800 km2 including the city of Rome. Here we report twenty-six new 40Ar/39Ar age analyses of pyroclastic and lava units in order to put time constraints on the most recent SVD eruptive activity (i.e. post-dating 400 ka), as a groundwork for a detailed reconstruction of the whole volcano-tectonic evolution. Integrated geochronological and field evidence shows that SVD volcanism maintained a typical areal character through the whole history: both effusive and explosive activity phases from different source areas and volcano-tectonic settings overlapped in time and space, while climactic phases migrated repeatedly through time. In particular, new geochronological data better constrain a climactic phase of activity at around 300 ka, related to the Bracciano volcano-tectonic depression and the Sacrofano caldera, and point out that the most recent eruptive activity in the SVD took place from time–space-clustered hydromagmatic centres at least up to 90 ka. In addition, we remark some parallelism among major activity phases in the SVD and the nearby districts of the Roman Province, with possible implications on Quaternary regional tectonics. Finally, new age data put constraints on tephrostratigraphic correlations through the Apennine Chain and the Adriatic Sea.

Textural and chemical variations of juvenile clasts are widely observed in pyroclastic deposits. In particular, the co-existence of whitish, pumiceous, and dark grey, scoriaceous, juvenile clasts has been observed in many eruptive units of well-known volcanoes (i.e., Somma-Vesuvius, Vulsini, Colli Albani, Stromboli). Here we report the example of the Tufo Giallo della Via Tiberina (TGVT) pyroclastic succession, which comprises two eruptive units emplaced at ca. 561 and 548ka, during the early explosive activity of the Sabatini Volcanic District (SVD; Roman Province, central Italy). TGVT deposits, as well as underlying pyroclastic products (FAD, ca. 582ka), are characterized by coexisting whitish pumice and black-grey scoria clasts showing common phonolitic composition but different textural features: white pumice is highly vesicular, vitrophyric, and contains scarce, >50μm-sized, feldspar and clinopyroxene crystals, while black-grey scoria is poorly vesicular, highly crystallized, and contains diffuse leucite phenocrysts. The latter records crystallization under H2O-undersaturated conditions, as opposed to the vitrophyric texture of white pumice indicating higher temperature and H2O concentration. On these grounds, a thermally and H2O-zoned pre-eruptive system has been modelled for the phonolitic magma chambers feeding the early SVD events, in which white pumice and black-grey scoria represent the inner and peripheral portions of the reservoirs, respectively. Extensive leucite+clinopyroxene crystallization in the H2O-undersaturated, peripheral portions of the reservoirs, resulted in water flux toward the inner zones, where the higher temperature and increasing H2O content acted to delay crystallization in the white pumice-feeder magma. The withdrawal of white pumice at the eruption onset produced decompression of the peripheral magma, triggering black-grey scoria eruption during the late phases of explosive events. © 2010 Elsevier B.V.

Hydromagmatic eruptions convert thermal into mechanical energy via the expansion of ground- and/or surface-water. Several models address the energetics of these eruptions based on different physical-volcanological approaches. Here we test different models with two case studies in the Colli Albani Volcanic District (central Italy): the monogenetic Prata Porci and the polygenetic Albano maars. Test results are mutually consistent, and show cumulative mechanical energy releases on the order of 1015–1017 J for single maars. The fraction of thermal energy turned into mechanical ranges from 0.45 (as calculated from the theoretical maximum mechanical energy), through 0.1 (calculated from country rock fragmentation, crater formation and ballistic ejection), to 0.03 (derived from magma fragmentation by thermohydraulic explosions). It appears that the energy released during the most intense hydromagmatic events may account for a dominant fraction of the total mechanical energy released during the whole maar eruptive histories. Finally, we consider the role of magmatic explosive activity intervening during maar eruptions in causing departures from predictions of the models evaluated.

Large silicic explosive eruptions are the most catastrophic volcanic events. Yet, the intratelluric mechanisms underlying are not fully understood. Here we report a field and laboratory study of the Kos Plateau Tuff (KPT, 161 ka, Aegean Volcanic Arc), which provides an excellent geological example of conduit processes that control magma vesiculation and fragmentation during intermediate- to large-scale caldera-forming eruptions. A prominent feature of the KPT is the occurrence of quite unusual platy-shaped tube pumice clasts in pyroclastic fall and current deposits from the early eruption phases preceding caldera collapse. On macroscopic and SEM observations, flat clast faces are elongated parallel to tube vesicles, while transverse surfaces often occur at ~ 45° to vesicle elongation. This peculiar pumice texture provides evidence of high shear stresses related to strong velocity gradients normal to conduit walls, which induced vesiculation and fragmentation of the ascending magma. Either an increasing mass discharge rate without adequate enlargement of a narrow central feeder conduit or a developing fissure-like feeder system related to incipient caldera collapse provided suitable conditions for the generation of plate tube pumice within magma volumes under high shear during the pre-climactic KPT eruption phases. This mechanism implies that the closer to the conduit walls (where the stronger are the velocity gradients) the larger was the proportion of plate vs. conventional (lensoid) juvenile fragments in the ascending gas–pyroclast mixture. Consequently, plate pumice clasts were mainly entrained in the outer portions of the jet and convecting regions of a sustained, Plinian-type, eruption column, as well as in occasional lateral blast currents generated at the vent. As a whole, plate pumice clasts in the peripheral portions of the column were transported at lower altitudes and deposited by fallout or partial collapse closer to the vent relative to lensoid ones that dominated in the inner column portions. The plate tube pumice proportion decreased abruptly up to disappearance during the emplacement of the main pyroclastic currents and lithic-rich breccias related to extensive caldera collapse at the eruption climax, as a consequence of an overall widening of the magma feeder system through the opening of multiple conduits and eruptive vents, along with fissure erosion, concomitant to the disruption of the collapsing block.

Two main end-members of eruptive regimes are identified from analyses of high-speed videos collected at Stromboli volcano (Italy), based on vent conditions: one where the vent is completely clogged by debris, and a second where the vent is open, without any cover. By detailing the vent processes for each regime, we provide the first account of how the presence of a cover affects eruptive dynamics compared to open-vent explosions. For clogged vents, explosion dynamics are controlled by the amount and grain size of the debris. Fine-grained covers are entirely removed by explosions, favouring the generation of fine ash plumes, while coarse-grained covers are only partially removed by the explosions, involving minor amounts of ash. In both fine- and coarse-grained cases, in-vent ground deformation of the debris reflect variations in the volumetric expansion of gas in the conduit, with rates of change of the deformation comparable to ground inflation related to pre-burst conduit pressurization. Eruptions involve the ejection of relatively slow and cold bombs and lapilli, and debris is observed to both fall back into the vent after each explosion and to gravitationally accumulate between explosions by rolling down the inner crater flanks to produce the cover itself. Part of this material may also contribute to the formation of a more degassed, crystallized and viscous magma layer at the top of the conduit. Conversely, open-vent explosions erupt with hotter pyroclasts, with higher exit velocity and with minor or no ash phase involved.

We have refined the clinopyroxene-based hygrometer published by Armienti et al. (2013) for a better quantitative understanding of the role of H2O in the differentiation of Etnean magmas. The original calibration data set has been significantly improved by including several experimental clinopyroxene compositions that closely reproduce those found in natural Etnean products. To verify the accuracy of the model, some randomly selected experimental clinopyroxene compositions external to the calibration data set have been used as test data. Through a statistic algorithm based on the Mallows’ CP criterion, we also check that all model parameters do not cause data overfitting, or systematic error. The application of the refined hygrometer to the Mt. Etna 2011–2013 lava fountains indicates that most of the decreases in H2O content occur at P < 100 MPa, in agreement with melt inclusion data suggesting abundant H2O degassing at shallow crustal levels during magma ascent in the conduit and eruption to the surface.

The 1999 Revisions of the Individuals with Disabilities Education Act (IDEA), now known as the Individuals with Disabilities Education Improvement Act of 2004 (IDEIA), confirmed the legal role of foster parents in special education decision making on behalf of the youth in their care. The present study responded with a multiple case study of seven secondary special education teachers and their attitudes, experiences, and recommendations for collaboration with foster parents of adolescent youth. Collaborative theory was used to frame the study and analyze the data. The participants reported that they lacked full awareness of foster care and limited the scope of their collaboration to address youth's behavioral and vocational needs. This report includes noted gaps between the participants' accounts and the literature, and implications for ongoing research.

Metastatic/advanced colorectal cancer is considered a resistant disease and oncologic emergencies secondary to advanced disease may be regarded with a nihilistic attitude. The objective of this report is to emphasize the efficacy of the oxaliplatin/5-fluorouracil/leucovorin regimen (FOLFOX-4) in three patients presenting oncologic emergencies secondary to advanced colon cancer. The first case was a 40-year-old man with severe respiratory insufficiency due to massive carcinomatous lymphangitis; subsequently a cecal adenocarcinoma was diagnosed. The patient's conditions became life-threatening and he was admitted to the intensive care unit. The second case was a 41-year-old woman presenting with fever, abdominal mass and pain. Ultrasound and CT-scan revealed two hepatic masses (13 x 15 and 15 x 20 cm), diagnosed as liver metastases from colon cancer. The patient's condition deteriorated with intestinal obstruction secondary to the large left liver mass. The third case was a 58-year-old woman presenting with hepatic mass, fever and weight loss. Ultrasound and CT-scan showed a liver lesion occupying the right lobe (12 x 14 cm). Ultrasonically-guided biopsy and colonoscopy showed liver metastases from cecal cancer. A 5-fluorouracil/leucovorin regimen failed to improve her clinical condition and she had disease progression, inferior vena cava neoplastic thrombosis and right hydronephrosis. All three patients rapidly improved after a few cycles of oxaliplatin-containing chemotherapy. These cases demonstrate that even patients with advanced colorectal cancer presenting with oncologic emergencies and life-threatening conditions can be successfully treated with the FOLFOX-4 regimen.

The town of Biancavilla, located on the lower flanks of Mt. Etna volcano, eastern Sicily (Italy), showed high mortality rates owing to malignant pleural neoplasms, a cause of death specifically related to exposure to asbestos fibres. An environmental survey indicated the stone quarry site of “Il Calvario” as a possible source of asbestos fibre exposure, while a mineralogical study allowed to identify the new asbestiform mineral “fluoro-edenite”. A joint epidemiological and environmental study was conducted to assess the characteristics of the outbreak of malignant mesothelioma and to test the assumption of a causal relation with exposure to fluoro-edenite. Due to the lack of awareness of fluoro-edenite releases, Il Calvario may not be the only source of the fibre, but is probably the main one. The evolution of the volume of material quarried from Il Calvario was studied on the basis of maps printed from 1896 to 1995, by using a digital elevation model. The natural and anthropogenic causes of the territorial spread of the newly discovered amphibole fibres are discussed relatively to a geo-volcanological, territorial and environmental evolution of the area affected.

The early activity of the Sabatini Volcanic District (SVD; central Italy) was characterised by highly explosive eruptions that produced widespread subplinian and plinian fall deposits. In this study, four major eruptive units—informally named as units A, B, C and D—were recognised in the 514–449 ka age interval. In particular, unit D was emplaced during the early phase of the 449 ka Tufo Rosso a Scorie Nere pyroclastic flow-forming eruption, the most important event in the whole SVD activity history. Estimates of relevant eruptive parameters indicate tephra fall volumes up to 4 km3 for individual units, peak eruption column heights in the range of 14–29 km and corresponding mass eruption rates of 7.8×106–1.3×108 kg/s. Isopach and isopleth maps of fallout deposits—as well as the distribution of the proximal lag-breccia of the Tufo Rosso a Scorie Nere—consistently indicate a common vent area, which does not correspond to any volcanic centre identified up to now in the SVD. This was located along NE–SW-trending tectonic lineaments that also controlled the location of the other major volcanic centres of the SVD. The characterisation by means of field aspects, grain size, componentry and density and chemical composition of juvenile clasts, renders the studied fall deposits as valuable stratigraphic markers for the SVD and well beyond it. In fact, their wide areal dispersals toward the E and SE may allow correlations on a regional scale for the Quaternary successions of intermountain basins of the Central Apennine and the Adriatic Sea basin successions. Finally, the correct identification of distal tephra from plinian and co-ignimbrite plumes and their attribution to specific explosive eruptions of the SVD and the other volcanic districts of the Roman Province—rather than to local intra-Apennine centres—provides crucial implications for geodynamic reconstructions.

The solubility of H2O- and CO2-bearing fluids in trachytic and trachybasaltic melts from erupted magmas of the Campi Flegrei Volcanic District has been investigated experimentally at 1100 and 1200 °C, respectively, and at 100, 200, 300, 400, and 500 MPa. The solubility of H2O in the investigated melts varies between 3.48 ± 0.07 wt% at 100 MPa to 10.76 ± 0.12 wt% at 500 MPa in trachytic melts and from 3.49 ± 0.07 wt% at 100 MPa to 9.10 ± 0.11 wt% at 500 MPa in trachybasaltic melts. The content of dissolved CO2 in melts coexisting with the most CO2-rich fluid phase increases from 281 ± 24 ppm at 100 MPa to 2710 ± 99 ppm at 500 MPa in trachyte, and from 727 ± 102 ppm at 100 MPa to 3565 ± 111 ppm at 500 MPa in trachybasalt. Natural samples from the Campanian Ignimbrite eruption (trachyte) and from the Solchiaro eruption (trachybasalt) were collected around the city of Naples and on Procida Island. Deuterium/hydrogen (D/H) ratios were analyzed in natural pumices pre-heated at different temperatures to remove water adsorbed and/or imprinted by glass alteration processes. It has been determined that heating of the glass to 350 °C efficiently removes most of secondary water and the remaining concentrations represent primary magmatic water preserved in the erupted material. Hydrogen isotope composition (with δD values ranging between −70‰ and −110‰) and its correlation with bulk water content in selected pumice samples of the Campanian Ignimbrite eruption are consistent with isotopic fractionation between magmatic fluid and melt during degassing of erupting magma. Hence, the H2O and CO2 contents in natural glasses from pumice samples are considered as minimum estimates on volatile concentrations in the melt just prior to the eruption or at the fragmentation event. The water contents in natural glasses vary from 0.83 ± 0.07 to 3.74 ± 0.06 wt% for trachytes from the Campanian Ignimbrite eruption and from 1.96 ± 0.06 to 3.47 ± 0.07 wt% for trachybasalts from the Solchiaro eruption. The CO2 contents vary from 78 ± 120 ppm CO2 to 1743 ± 274 ppm for trachytes from the Campanian Ignimbrite eruption and from 240 ± 293 to 1213 ± 250 ppm for trachybasalts from the Solchiaro eruption. A combination of natural and experimental data provides minimum pressure estimates for the storage and ascent conditions of magmas. The Campanian Ignimbrite magma could have been stored or ponded during its rising path at two different levels: a deeper one corresponding to depth of about 8 to 15 km and a shallower one at about 1 to 8 km. Trachybasalts from Solchiaro erupted from the deepest level of about 11 km with a storage or ponding level at around 2 to 8 km depth. Although an uncertainty of at least a kilometer has to be considered in estimating storage or ponding depths, these estimates point to significantly deeper magmatic sources for both eruptions as those considered previously.

The uneven Earth’s spinning has been reported to affect geological processes, i.e. tectonism, seismicity and volcanism, on a planetary scale. Here, we show that changes of the length of day (LOD) influence eruptive activity at subduction margins. Statistical analysis indicates that eruptions with volcanic explosivity index (VEI) ≥3 alternate along oppositely directed subduction zones as a function of whether the LOD increases or decreases. In particular, eruptions in volcanic arcs along contractional subduction zones, which are mostly E- or NE-directed, occur when LOD increases, whereas they are more frequent when LOD decreases along the opposite W- or SW-directed subduction zones that are rather characterized by upper plate extension and back-arc spreading. We find that the LOD variability determines a modulation of the horizontal shear stresses acting on the crust up to 0.4 MPa. An increase of the horizontal maximum stress in compressive regimes during LOD increment may favour the rupture of the magma feeder system wall rocks. Similarly, a decrease of the minimum horizontal stress in extensional settings during LOD lowering generates a larger differential stress, which may enhance failure of the magma-confining rocks. This asymmetric behaviour of magmatism sheds new light on the role of astronomical forces in the dynamics of the solid Earth.

Catastrophic sedimentary processes associated with explosive eruptions represent a significant geologic hazard in volcanic areas. Here we report a striking historic example of an intermediate-scale explosive event whose environmental effects were strongly amplified by secondary rapid mass flows and hydrogeologic disasters. The 472 AD Pollena eruption of Somma-Vesuvius (Campania, Italy) took place in the critical period of the fall of the Western Roman Empire. On the basis of an integrated geologic–archaeologic study we point out evidence of human habitation at the time of the eruption, effects induced and recovery time in a wide territory of Campania, and how the eruption significantly accelerated the deterioration of the local society during the Late Ancient age. The eruption began with a pulsating, sustained eruption column, followed by pyroclastic surges and scoria flows. Hydromagmatism acted early in the event, different from the typical Plinian eruptions of Somma-Vesuvius. Specific facies associations of primary and secondary volcaniclastic deposits characterize three depositional domains, including the volcano slopes, the surrounding alluvial plains and the distal mountains of the Apennine Range. Both volcano slopes and distal mountain slopes supplied loose pyroclastic material to the hyperconcentrated floods and debris flows that spread across the alluvial plains. The great impact of secondary volcaniclastic processes arose from: (1) the high vulnerability of the territory due to its geomorphic context; (2) the humid climatic conditions; (3) the hydromagmatic character of the eruption; (4) the decline of land management at the end of the Roman Empire.

Differences in incidence and survival in osteosarcoma reports are considerable worldwide.This study describes the incidence and survival of patients with osteosarcoma in Argentina with data from the National Pediatric Cancer Registry (ROHA), and the impact of age, gender, stage, regional, and socioeconomic indicators on outcome.Pediatric patients with osteosarcoma reported to ROHA from 2000 through 2013 were analyzed, the annual age-standardized incidence rate (ASR) was calculated using the National Vital Statistics, and survival was estimated. The extended human development index (EHDI) for each reporting region was used as an indicator of socioeconomic status.There were 515 cases of osteosarcoma identified, yielding an ASR of 3.2/1,000,000 children (0-14 years old). The ASR did not vary significantly by year of diagnosis but ranged from 4.0/1,000,000 in the Cuyo/Western Central region to 2.7/1,000,000 in the northeast region (P0.000). The estimated 5-year survival rate was 45% (95% confidence interval [CI] 44-51%), with no difference by sex, diagnosis year, region, or EHDI score (P0.1 in all cases). Survival rate for localized disease was 52% (95% CI 45-57%) and for metastatic 22% (95% CI 15-30%).In Argentina, ASR of osteosarcoma is similar to that in high-income countries, but survival is lower in all regions. Future work will focus on identification and reduction of causes of preventable treatment failure.

Most studies of volcaniclastic facies and aggradation cycles have been conducted in regions with humid climates, and on regional scales. Here we document a volcaniclastic succession that formed in a semiarid climate characterized by rare, heavy rains onto a relatively barren volcanic landscape on Vulcano Island, Italy. The deposits, which we informally call the Cuesta succession, occur in a small valley between two rhyolite domes, and consist of a sequence of pyroclastic surge and fallout deposits interbedded with their reworked equivalents. A phase of eruptive activity characterized by sporadic hydrovolcanic explosions supplied ash to the valley and its flanks. Runoff events during the eruptive phase continually washed ash down to the valley floor in the form of hyperconcentrated flows. The inferred transport mechanism and depositional facies of these beds reflect the control of primary volcanic fragmentation processes on sedimentation; the abundant, medium-to-coarse ash supplied by eruption was incorporated sufficiently easily into the runoff to hyperconcentrate the flows, but not sufficiently fine grained to make the flows cohesive. These flows moved out onto the floor, merged, and transported ash down the valley axis, depositing the ash as a monotonous succession of massive to faintly laminated beds. The combination of primary deposits and the deposits washed off the valley flanks led to aggradation of the valley floor. As eruptions waned, ash was eroded off the flanks faster than it was replenished, leading to a stratigraphic upward increase in lithic clasts derived from the underlying lavas and a wider range of sedimentary facies as the ash load became more variable. After eruptions ceased and all remaining ash was removed from the flanks, aggradation gave way to degradation to form small canyons that expose the succession.

The angular velocity of Earth's rotation shows decadal oscillations due to the lunisolar gravitational torque, as well as inter- or intra-annual changes arising from the angular momentum exchange between the atmosphere and the solid Earth. The energies involved in the Length of Day (LOD) variations may affect the crustal deformation rate and seismic energy release on a global scale. We found significant correlation between the occurrences of major volcanic eruptions and the LOD pattern since AD 1750. On a multiyear scale, eruption frequency worldwide increases with LOD changes. Moreover, the injection of sulphur gases into the atmosphere during major eruptions is accompanied by significant inter-annual LOD variations. This provides evidence of complex mutual cause-and-effect interactions: stress changes induced by multiyear variations in Earth's spin may affect climactic volcanic activity; also, the atmosphere's dynamic response to volcanic plumes may result in global changes of wind circulation and climate, with consequent LOD variations. © 2013 John Wiley & Sons Ltd.

Textural and compositional features of pyroclastic products erupted during caldera-forming events often reveal the tapping of different portions of variably zoned magma chambers due to changing geometries of the conduit/vent systems. Here we report on ultrapotassic trachytic–phonolitic explosive eruptions of the Roman Province (central Italy), which show remarkable changes of textural features and glass compositions in the juvenile material, even if the bulk chemical composition is essentially constant. In each example, the lower eruption sequence contains whitish, crystal-poor (leucite-free), highly vesicular pumice, emplaced by early Plinian fallout and/or pyroclastic currents; upsection, the eruption sequence contains black, low porphyritic (sanidine + leucite-bearing), moderately vesicular, scoria or spatter, emplaced by major pyroclastic flows (red tuff with black scoria) and associated co-ignimbrite, coarse lithic-rich breccias. This suggests a shift from a central feeder conduit, tapping the central part of the magma chamber, to a ring fracture vent system, tapping the peripheral portions of the magma chamber, during caldera collapse. Key features of these evacuating magma chambers are the thermal and volatile concentration (Xvol) gradients that produce the observed textural and compositional spectrum of trachy-phonolitic rock types. In particular, the degrees of freedom during the crystallization of these ultrapotassic magmas are increased by the variation of the leucite stability field at different PH2O conditions. Both leucite-free and leucite-bearing differentiated ultrapotassic rock types can be produced in the course of individual eruptions, as a result of pre-eruptive conditions in the feeder magma, with no need to invoke different differentiation suites related to mantle source heterogeneities of parental magmas.

The serotonergic (5-HT) function of 36 mothers of heroin addicts, of whom 16 subjects were without psychopathological features (group A) and 20 subjects had major depressive disorders (group B), as well as 10 age- and sex-matched healthy controls, was examined by L-D-fenfluramine stimulation of secretion of prolactin (PRL) and cortisol. The subjects' addict relatives were also tested for personality features and hormonal responses to L-D-fenfluramine. The PRL and cortisol responses to the stimulus were normal in mothers of group A, and blunted in mothers of group B. A high frequency (70%) of heroin addicts with comorbid depression was found among the sons of group B mothers. The sons of depressed mothers showed reduced PRL and cortisol responses to fenfluramine. A significant direct correlation has been demonstrated between the PRL areas under curves (AUC) of mothers and sons in response to the 5-HT agonist. Our data suggest that genetic 5-HT impairment is not involved in the pathogenesis of heroin addiction or codependence per se, and is probably linked to the presence of familial depression in comorbidity with the addictive disorder.

Widely dispersed pyroclastic fall deposits are prominent among the volcanic products of the western part of the Vulsini Volcanic District (central Italy). In this paper we describe major pumice fall deposits in the area, that correlate to the early activity of the Latera Volcanic Complex (0.3-0.2 Ma). They represent excellent stratigraphie markers for a wide area mostly extending west and south of the present Latera caldera. Pumice fall deposits lower B and upper B are closely associated with major pyroclastic flow units of the Canino Eruptive Unit; pumice fall C caps the Canino products without relevant time hyatus. Pyroclastic falls D and E, the latter part of the minor Stenzano explosive eruption, belong to the stratigraphic interval between Canino and Farnese eruptive units. Pumice fall F is part of the initial products of the Farnese eruptive sequence. We present detailed stratigraphy, depositional features, vertical and lateral variations of grain size, componentry and chemical composition in individual fallout beds. Source areas, as inferred from thickness and maximum pumice and lithic clast size distributions, are located in the area of the present-day Latera caldera. Tentative estimates of volume, column height and magma discharge rate indicate moderate-large to large Plinian eruptive events.

[1] The identification and evaluation of trigger mechanisms for volcano flank instabilities and/or collapse represent a key issue for risk assessment in densely populated volcanic areas, as well as in long-distance settings, particularly in case of island or coastal volcanoes. Here we address quantitatively the effects of external (seismic) and inner (magmatic) forcing on the stress-strain state associated to flank instabilities at Mount Etna (Sicily, southern Italy) by means of a 2-D finite difference method numerical modeling. Modeled seismic actions include strong near-field, strong far-field, and low-magnitude near-field earthquakes. Magmatic actions consider the inner pressure changes induced by energetic lava fountains in the summit crater area and subvertical and oblique dike ascent below the summit area. Model results are validated in light of available monitoring data and recent eruptive activity. Numerical results show that the main strain effects are produced by high-magnitude near-field earthquakes (expected return time of ~103 yrs) and by vertical uprise of a magma dike below the volcano summit area. Maximum displacements in the order of tens of centimeters may involve the summit area, up to some 106 m3/m over some kilometers laterally. Stress releases up to 107 Pa may affect a limited portion of the magmatic conduit, thus favoring major effusive flank eruptions. Major catastrophic events, such as volcano flank collapse, should not be expected by applying, either individually or combined, the aforementioned actions.

The first results of the LIFE+ SOILCONSWEB project that aims to combine digital soil mapping, soil modeling, digital soil databases and land assessment to produce, to test and to apply a Spatial Decision Supporting System (S-DSS) are shown. The practical focus of this system is to support (stakeholders) decision on landscape issues aiming to both the best soil conservation and agricultural land management. The S-DSS system is being developed, tested and applied in an area of about 20,000 hectares in South Italy (Valle Telesina, province of Benevento in the Campania region). The system acknowledge that soils and landscapes have the well recognized "multiple functions" as a fundamental feature. Then it is not surprising that this decision supporting system requires, as fundamental feature, to include and mix many different high quality digital information, engine and processing in order to be successfully applied. Our web-based S-DSS system includes modeling procedures at different level of complexity. Here we present tools calculating soil water/solute balance using Richards' based modeling on benchmark soils of the different 47 soil types. This Soil-Plant-Atmosphere (SPA) modeling is used for different purposes including among others (i) estimate of vineyard water stress (affecting wine quality), (ii) estimate of loss of hydrological soil function due to soil sealing, (iii) soil protective capacity towards groundwater pollution expressed by the outflow/inflow ratio. The SPA model is based on the original desktop based SWAP model (Kroes et al, 2008) and enables to be run "on the fly" through the web S-DSS system. The user at this stage can choose between different options including: area (farm, municipality, district, or just drawing the polygon of interest), crop (olive, grapes, maize, bare soil) and date interval for the simulation run. Others options will be further implemented. The S-DSS system every day acquires spatialized data for the upper boundary condition (rainfall and temperatures to estimate ET0 by the Heargraves model) as input for the SPA model running. Hydraulic properties of each soil horizon of the 47 soil profiles were measured in the laboratory by the Wind's method and estimated through HYPRES PTF. Water retention and hydraulic conductivity relationships were parameterized according to the van Genuchten-Mualem model; lab-derived parameters were scaled to field condition by taking into account the coarse fragment content (from the pedological survey) and the hysteretic field behavior of the soil water retention curve. Initial condition was set to h=-50 cm along the soil profile. The simulation starts the 1st January 2011 to manage uncertainty in initial conditions setting. Examples of outcomes are the soil water storage at different depths, inflow/outflow ratio, ETa/ET0, but many others can be implemented, showing the potentiality of the system to allow different scenarios in many field of interest where the balance of the water in the system soil-plant-atmosphere is required. Then decision makers (individuals, groups of interests and public bodies) can have real-time (or near real-time) access to critical, accurate, complete and up-to-date spatial data/output models held/processed in multiple data stores. The system produce detailed spatial documents, report and maps on a series of questions including agriculture, environment and climate change. The tool is available at www.landconsultingweb.eu/.

Summary A series of aryloxyalkylthioimidazoles have been synthesized and evaluated for their ability to interfere with the enzyme acyl-CoA (cholesterol- O -acyltransferase) (ACAT, EC 2.3.1.26). Most of the molecules possessed a good in vitro ACAT inhibitory activity with IC 50 values ranging between 0.1 and 2.0 μM. Some of them, eg , 2-5-[(4-isobutoxycarbonyl)phenoxy]-pentylthio-4,5-diphenylimidazole 13 , 2-3-[(4-isobutoxycarbonyl)phenoxy]-2-oximinopropylthio-4,5-diphenylimidazole 21 , 2-3-[(4-isobutoxycarbonyl)phenoxy]-2-hydrazonecarboxamidepropylthio-4.5-diphenylimidazole 26 , 2-[5-(2-pyridoxy)-pentylthio]-4,5-diphenylimidazole 40 and 2-5-[(3,5-diterbutyl-4-hydroxy)phenylthio]pentylthio-4,5-diphenylimidazole 42 , were more potent (range of activity 10–90 nM). They were also more potent with respect to the reference CI-976. When administered orally in hyperlipemic rats, at 10 and 50 mg/kg doses, some representative compounds, like 2-3-[(4-isobutoxycarbonyl)phenoxy]-2-hydroxypropylthio-4, 5-diphenylimidazole 1, 13 and 26 , reduced VLDL/LDL-associated cholesterol levels by 30–50% and increased HDL cholesterol levels by 15–50%. In addition, liver accumulation of esterified cholesterol was counteracted (50–80% reduction) and liver ACAT ex vivo activity was decreased by 70–85%. Finally, the good efficacy displayed in an endogenous model of hypertriglyceridemia strongly supports the hypothesis of a good systemic availability, which constitutes one of the principal properties of a valuable ACAT inhibitor.

[1] Explosive volcanic activity on Earth is typically discontinuous in space and time. The occurrence of spatial/temporal eruption clusters due to mutual cause-and-effect relationships or external triggers (e.g., tectonic and/or tidal forcing) is still debated. To detect possible clustering of major explosive eruptions, we test the distribution of eruptions with Volcanic Explosivity Index (VEI) ≥ 4 from 1750 to present. The 143 documented VEI ≥ 4 events display a markedly non-uniform frequency distribution, with the highest relative probability of eruption recurrence within 500 km distance from the preceding event. The analogous frequency pattern obtained from randomized data series of the same catalogue suggests that the observed eruption pattern is primarily imparted by the geodynamic distribution of volcanoes (mostly located along tectonically active linear belts), with no evidence of mutual or external influence. Our results highlight a counter-intuitive array of major eruption loci as a consequence of the intrinsic worldwide asymmetry of explosive volcanism, with implications on hazard assessment.

Shiga toxin-producing Escherichia coli (STEC) cause nonbloody (NBD) and bloody diarrhea (BD), and hemolytic uremic syndrome (HUS). Cattle have been described as their main reservoir. STEC O157:H7 is recognized as the predominant serotype in clinical infections, but much less is known about the dominant subtypes in humans and animals or their genetic relatedness. The aims of this study were to compare the STEC O157 subtypes found in sporadic human infections with those in the bovine reservoir using stx-genotyping, phage typing, and XbaI-pulsed-field gel electrophoresis (PFGE), and correlate the subtypes with the severity of clinical manifestations. The 280 STEC O157:H7 strains collected included in this study were isolated from HUS (n=122), BD (n=69), and NBD (n=30) cases, and healthy carriers (n=5), and from bovines (n=54) in the abattoirs. The stx-genotyping showed that stx2/stx2c(vh-a) was predominant in human (76.1%) and in bovine strains (55.5%), whereas the second more important genotype was stx2 (20.8%) in human and stx 2c(vh-a) (16.7%) in cattle strains. In human strains, PT4 (37.6%), PT49 (24.3%), and PT2 (18.6%) were the most frequent PTs (80.5%). In bovine isolates, PT2 (26%), PT39 (16.7%), and PT4 and PT49 (11.1% each) were predominant. By XbaI-PFGE, all 280 strains yielded 148 patterns with 75% similarity, and 169 strains were grouped in 37 clusters. Identical PT-PFGE-stx profile combinations were detected in strains of both origins: PT4-AREXH01.0011-stx2/stx2c(vh-a) (12 humans and one bovine), PT4-AREXH01.0543-stx2/stx2c(vh-a) (one human and four bovines), PT2-AREXH01.0076-stx2/stx2c(vh-a) (one human and four bovines), PT49-AREXH01.0175-stx2/stx 2c(vh-a) (seven humans and one bovine), and PT49-AREXH01.0022- stx2/stx2c(vh-a) (seven humans and one bovine). No correlation was found among the stx-genotypes, the phage type, and the clinical symptoms. Fil: D´Astek, Beatriz. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina Fil: del Castillo, Lourdes Leonor. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Agroindustria. Instituto de Tecnología de Alimentos; Argentina Fil: Miliwebsky, Elizabeth. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina Fil: Carbonari, Claudia Carolina. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina Fil: Palladino, Pablo Martín. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Agroindustria. Instituto de Tecnología de Alimentos; Argentina Fil: Deza, Natalia. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina Fil: Chinen, Isabel. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina Fil: Manfredi, Eduardo. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina Fil: Leotta, Gerardo Anibal. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; Argentina Fil: Masana, Marcelo. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina Fil: Rivas, Marta. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina

In Italy, rainfall-induced slope failures occur every year, claiming lives and causing severe economic damage. We have designed and implemented a landslide warning system, named SANF (an acronym for national early warning system for rainfall-induced landslides), to forecast the possible occurrence of rainfall-induced landslides in Italy. The system is based on: (i) rainfall thresholds for pos- sible landslide occurrence, (ii) sub-hourly rainfall measurements obtained by a national network of 1950 rain gauges, and (iii) quantitative rainfall forecasts. Twice a day, the system compares the measured and the forecasted rainfall amounts against pre-defined ID thresholds, and assigns to each rain gauge a prob- ability of landslide occurrence. This information is used to prepare synoptic-scale maps showing where rainfall-induced landslides are expected in the next 24 hours.

Benford's analysis is applied to the recurrence times of approximately 17,000 seismic events in different geological contexts of Italy over the last 6 years, including the Mt. Etna volcanic area and the seismic series associated with the destructive M (w) 6.3, 2009 L'Aquila earthquake. A close conformity to Benford's law and a power-law probability distribution for the recurrence times of consecutive events is found, as typical of random multiplicative processes. The application of Benford's law to the recurrence event times in seismic series of specific seismogenic regions represents a novel approach, which enlarges the occurrence and relevance of Benford-like asymmetries, with implications on the physics of natural systems approaching a power law behaviour. Moreover, we propose that the shift from a close conformity of Benford's law to Brownian dynamics, observed for time separations among non-consecutive events in the study seismic series, may be ruled by a periodical noise factor, such as the effects of Earth tides on seismicity tuning.

Explosive volcanic eruptions are defined as the violent ejection of gas and hot fragments from a vent in the Earth's crust. Knowledge of ejection velocity is crucial for understanding and modeling relevant physical processes of an eruption, and yet direct measurements are still a difficult task with largely variable results. Here we apply pioneering high-speed imaging to measure the ejection velocity of pyroclasts from Strombolian explosive eruptions with an unparalleled temporal resolution. Measured supersonic velocities, up to 405 m/s, are twice higher than previously reported for such eruptions. Individual Strombolian explosions include multiple, sub-second-lasting ejection pulses characterized by an exponential decay of velocity. When fitted with an empirical model from shock-tube experiments literature, this decay allows constraining the length of the pressurized gas pockets responsible for the ejection pulses. These results directly impact eruption modeling and related hazard assessment, as well as the interpretation of geophysical signals from monitoring networks.

A series of purine derivatives have been prepared and their in vivo abilities to lower plasma total cholesterol and triglyceride levels, and to elevate high density lipoprotein (HDL) cholesterol levels in hyperlipemic rats have been tested. Some compounds, among which 8-{2-( R )-hydroxy-3-[( p -isobutoxycarbonyl)phenoxy]propylthio}adenosine 31 , 8-{3-[( p -isobutoxycarbonyl)phenoxy]-2-oxopropylthio} adenosine 33 and 8-{3-[( p -isobutoxycarbonyl)phenoxy]-2-hydrazonecarboxamidepropylthio} adenosine 36 appear to be the most interesting, have been found to have both the desired profile of activity and no hepatotoxicity, when administered po at 50, 100 or 300 mg/kg. Compounds 31, 33 and 36 , orally tested at the same doses in the 15-d test, lower triglyceride and VLDL/LDL (very low density lipoprotein/low density lipoprotein) cholesterol levels by 10–33% and 13–46%, respectively, and increase HDL-associated cholesterol levels by 10–32%. These molecules have been chosen for further pharmacological and toxicological evaluations.

The non-O157 Shiga toxin-producing Escherichia coli (STEC) contamination in carcasses and feces of 811 bovines in nine beef abattoirs from Argentina was analyzed during a period of 17 months. The feces of 181 (22.3%) bovines were positive for non-O157 STEC, while 73 (9.0%) of the carcasses showed non-O157 STEC contamination. Non-O157 STEC strains isolated from feces (227) and carcasses (80) were characterized. The main serotypes identified were O178:H19, O8:H19, O130:H11, and O113:H21, all of which have produced sporadic cases of hemolytic-uremic syndrome in Argentina and worldwide. Twenty-two (7.2%) strains carried a fully virulent stx/eae/ehxA genotype. Among them, strains of serotypes O103:[H2], O145:NM, and O111:NM represented 4.8% of the isolates. XbaI pulsed-field gel electrophoresis pattern analysis showed 234 different patterns, with 76 strains grouped in 30 clusters. Nine of the clusters grouped strains isolated from feces and from carcasses of the same or different bovines in a lot, while three clusters were comprised of strains distributed in more than one abattoir. Patterns AREXSX01.0157, AREXBX01.0015, and AREXPX01.0013 were identified as 100% compatible with the patterns of one strain isolated from a hemolytic-uremic syndrome case and two strains previously isolated from beef medallions, included in the Argentine PulseNet Database. In this survey, 4.8% (39 of 811) of the bovine carcasses appeared to be contaminated with non- O157 STEC strains potentially capable of producing sporadic human disease, and a lower proportion (0.25%) with strains able to produce outbreaks of severe disease. Fil: Masana, Marcelo. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Agroindustria. Instituto de Tecnología de Alimentos; Argentina Fil: D´Astek, B. A.. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina Fil: Palladino, Pablo Martín. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Agroindustria. Instituto de Tecnología de Alimentos; Argentina Fil: Galli, Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; Argentina. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas; Argentina Fil: del Castillo, Lourdes Leonor. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Agroindustria. Instituto de Tecnología de Alimentos; Argentina Fil: Carbonari, Claudia Carolina. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas; Argentina Fil: Leotta, Gerardo Anibal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; Argentina. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas; Argentina Fil: Vilacoba, Elisabet. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas; Argentina Fil: Irino, K.. Instituto Adolfo Lutz. Seção de Bacteriologia; Brasil Fil: Rivas, M.. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas; Argentina

We investigate the potential impact of accounting for seasonal variations in the climatic forcing and using different methods to parameterize the soil water content at field capacity on the water balance components computed by a bucket model (BM). The single-layer BM of Guswa et al. (2002) is employed, whereas the Richards equation (RE) based Soil Water Atmosphere Plant (SWAP) model is used as a benchmark model. The results are analyzed for two differently-textured soils and for some synthetic runs under real-like seasonal weather conditions, using 100 time-series of stochastically-generated daily rainfall data. Since transient soil-moisture dynamics and climatic seasonality play a key role in certain zones of the World, such as in Mediterranean land areas, a specific feature of this study is to test the prediction capability of the bucket model under a condition where seasonal variations in rainfall are not in phase with the variations in plant transpiration and. Reference is made to a hydrologic year in which we have a rainy period (starting 1 November and lasting 151 days) where vegetation is basically assumed in a dormant stage, followed by a drier and rainless period with a vegetation regrowth phase. Better agreement between BM and RE-SWAP intercomparison results are obtained when BM is parameterized by a field capacity value determined through the drainage method proposed by Romano and Santini (2002). Depending on the vegetation regrowth or dormant seasons, rainfall variability within a season results in transpiration regimes and soil moisture fluctuations with distinctive features. During the vegetation regrowth season, transpiration exerts a key control on soil water budget with respect to rainfall. During the dormant season of vegetation, the precipitation regime becomes an important climate forcing. Simulations also highlight the occurrence of bimodality in the probability distribution of soil moisture during the season when plants are dormant, reflecting that soil, it being of coarser or finer texture, can be preferentially in either wetter or drier states over this period.

A series of purine derivatives have been prepared and their in vivo abilities to lower plasma total cholesterol and triglyceride levels, and to elevate high density lipoprotein (HDL) cholesterol levels in hyperlipemic rats have been tested. Some compounds, among which 8-{2-( R )-hydroxy-3-[( p -isobutoxycarbonyl)phenoxy]propylthio}adenosine 31 , 8-{3-[( p -isobutoxycarbonyl)phenoxy]-2-oxopropylthio} adenosine 33 and 8-{3-[( p -isobutoxycarbonyl)phenoxy]-2-hydrazonecarboxamidepropylthio} adenosine 36 appear to be the most interesting, have been found to have both the desired profile of activity and no hepatotoxicity, when administered po at 50, 100 or 300 mg/kg. Compounds 31, 33 and 36 , orally tested at the same doses in the 15-d test, lower triglyceride and VLDL/LDL (very low density lipoprotein/low density lipoprotein) cholesterol levels by 10–33% and 13–46%, respectively, and increase HDL-associated cholesterol levels by 10–32%. These molecules have been chosen for further pharmacological and toxicological evaluations.

Summary A series of aryloxyalkylthioimidazoles have been synthesized and evaluated for their ability to interfere with the enzyme acyl-CoA (cholesterol- O -acyltransferase) (ACAT, EC 2.3.1.26). Most of the molecules possessed a good in vitro ACAT inhibitory activity with IC 50 values ranging between 0.1 and 2.0 μM. Some of them, eg , 2-5-[(4-isobutoxycarbonyl)phenoxy]-pentylthio-4,5-diphenylimidazole 13 , 2-3-[(4-isobutoxycarbonyl)phenoxy]-2-oximinopropylthio-4,5-diphenylimidazole 21 , 2-3-[(4-isobutoxycarbonyl)phenoxy]-2-hydrazonecarboxamidepropylthio-4.5-diphenylimidazole 26 , 2-[5-(2-pyridoxy)-pentylthio]-4,5-diphenylimidazole 40 and 2-5-[(3,5-diterbutyl-4-hydroxy)phenylthio]pentylthio-4,5-diphenylimidazole 42 , were more potent (range of activity 10–90 nM). They were also more potent with respect to the reference CI-976. When administered orally in hyperlipemic rats, at 10 and 50 mg/kg doses, some representative compounds, like 2-3-[(4-isobutoxycarbonyl)phenoxy]-2-hydroxypropylthio-4, 5-diphenylimidazole 1, 13 and 26 , reduced VLDL/LDL-associated cholesterol levels by 30–50% and increased HDL cholesterol levels by 15–50%. In addition, liver accumulation of esterified cholesterol was counteracted (50–80% reduction) and liver ACAT ex vivo activity was decreased by 70–85%. Finally, the good efficacy displayed in an endogenous model of hypertriglyceridemia strongly supports the hypothesis of a good systemic availability, which constitutes one of the principal properties of a valuable ACAT inhibitor.

Cored bombs, a kind of pyroclast consisting of a lithic core surrounded by a chilled shell of juvenile material, record the thermal interaction of magma with wall rocks. We performed textural analysis of cored bombs, solid–melt heat-transfer theoretical modelling, and high-temperature coating experiments to put temporal and intensity constraints on the thermal interaction of potassic magma feeder systems with carbonate wall rocks during explosive eruptions in the Quaternary, Colli Albani Volcanic District (Roman Province). It appears that the degree of thermal alteration of lithic cores records the duration of magma-core heat transfer, whereas the core/shell size ratio records the initial entrainment temperature of the lithic fragment. Both parameters appear to vary significantly with the eruptive style, magnitude and vent location. Specifically, small-scale (~ 0.1–1 km 3 DRE) hydromagmatic eruptions show magma-core heat-transfer durations of 0.1–10 s and entrainment temperatures in the range of 100–300 °C in the case of a monogenetic maar located in the Colli Albani peripheral area, while entrainment temperature is as high as to 800 °C for a polygenetic maar in a high-enthalpy geothermal system at the margins of the main Colli Albani magma chamber. A large-scale (~ 30 km 3 DRE) caldera-forming explosive event shows magma-core heat-transfer duration in the order of 10 2 –10 3 s and temperature of 100–500 °C at the initial magma–wall rock contact. On these grounds, we derived the cooling rate of magmas as a function of the initial temperature, mass and size distribution of lithic clasts entrained. Magma cooling by lithic entrainment may have occurred on the same time-scale as that of eruptive pulses (seconds to hours), implying that lithic entrainment may effect changes in magma physico-chemical properties on a short time-scale and, consequently, affect eruptive conduit dynamics.