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Simple Summary: Thermal therapies, the controlled heating of tissue, are a clinically accepted modality for the treatment of localized cancers and are under investigation as part of treatment strategies for pancreatic cancer. The bioeffects of heating varies as a function of intensity and duration of heating and can vary across tissue types. We report on the measurement of thermal injury parameters for pancreatic cancer cell lines in vitro and assess their suitability for predicting changes in cell viability following heating. The results of this study may contribute to research investigating the use of thermal therapies as part of pancreatic cancer treatment strategies, the development of modeling tools for predictive treatment planning of thermal therapies, and understanding the effects of other energy-based interventions that may involve perturbation of tissue temperature. Thermal therapies are under investigation as part of multi-modality strategies for the treatment of pancreatic cancer. In the present study, we determined the kinetics of thermal injury to pancreatic cancer cells in vitro and evaluated predictive models for thermal injury. Cell viability was measured in two murine pancreatic cancer cell lines (KPC, Pan02) and a normal fibroblast (STO) cell line following in vitro heating in the range 42.5–50 °C for 3–60 min. Based on measured viability data, the kinetic parameters of thermal injury were used to predict the extent of heat-induced damage. Of the three thermal injury models considered in this study, the Arrhenius model with time delay provided the most accurate prediction (root mean square error = 8.48%) for all cell lines. Pan02 and STO cells were the most resistant and susceptible to hyperthermia treatments, respectively. The presented data may contribute to studies investigating the use of thermal therapies as part of pancreatic cancer treatment strategies and inform the design of treatment planning strategies. [ABSTRACT FROM AUTHOR]

The numerous volcanic centres in the Main Ethiopian Rift (MER) present significant but poorly understood hazards to local populations. The MER is also an important site to gain insights into tectonic processes as it captures the transition from continental rifting (to the south) to incipient seafloor spreading (to the north). Peralkaline magmas account for around 90% of the volcanic products found in the MER. Determining the conditions under which these magmas evolve is critical to understanding rift-related volcanism and its associated hazards. Corbetti Caldera has an extensive record of large-scale, predominantly aphyric, peralkaline rhyolite eruptions. However, little is known about the mafic magmas from which these highly differentiated melts have evolved. Here we present data from the only basaltic deposit found within the caldera, coupled with whole rock, glass and mineral analysis of the peralkaline products, to investigate magma storage conditions at Corbetti. We demonstrate that magma mixing played a role in the evolution of the basaltic magmas and use RhyoliteMELTS modelling to show Corbetti's peralkaline magmas likely evolved at pressures between 100 and 250 MPa, from a magma with an initial water content of 0.5–1 wt%, at or below the QFM buffer. Mineral hygrometry on the sparse crystal populations corroborates the RhyoliteMELTS modelling, suggesting that the basaltic magma had 0.1–1.2 ± 0.32 wt% H 2 O, and the peralkaline magmas an average of ∼5.5 ± 1.25 wt% H 2 O. These results also match melt inclusion data for Corbetti and other peralkaline systems. We also provide new 40Ar/39Ar ages for two eruptions, a pre-caldera rhyolitic lava flow (206.7 ± 0.9 ka) and a post-caldera peralkaline ignimbrite (160 ± 0.8 ka). These results add to our understanding of the history of Corbetti and the storage conditions of peralkaline magmas within a continental rift setting and highlight the hydrous nature of Corbetti's magmas and the role that H 2 O plays during explosive eruptions. • We present new data from the only known basaltic units within Corbetti Caldera. • We determine shallow magma storage conditions between 100 and 250 MPa at temperatures ∼1100 °C for the basaltic magma and ∼ 793 °C for the peralkaline magma. • Corbetti's magmas are hydrous with ∼5.5 wt% H 2 O. • We date a pre-caldera lava flow to ∼207 ka and a post-caldera ignimbrite to 160 ka [ABSTRACT FROM AUTHOR]

An 11-month-old infant girl presented to our office for evaluation of an asymptomatic lesion on her right thigh. Histologic characterization of the lesion is essential as it displays unique characteristics that aid in delineation from lesions in its differential diagnosis. Treatment options vary for EAH depending on the severity of the lesion and symptomatology. [Extracted from the article]

The globally-observed relationship between oceanic barium and the macronutrient silicic acid results from the shared influence of large-scale ocean circulation and mixing on the two elements, and the inherent link between barium and organic matter formation and dissolution. A detailed examination of deviations from barium-silicon correlations can reveal variations in non-conservative processes within the marine barium cycle. Here, we present a high-resolution dataset of dissolved barium and macronutrients from the Drake Passage and the Scotia and Weddell Seas. Our new results highlight the influence of Southern Ocean frontal zones on barium cycling and the deviations of barium and macronutrient distributions as a result of spatial variations in phytoplankton assemblages and in barite formation processes. These new data also reinforce findings that water mass mixing and ocean circulation, in particular the location of oxygen minima, play a key role in barium distribution. Our findings have implications for the use of sedimentary barium as a proxy for export production, which may be complicated by physical water circulation changes or shifts in plankton community structure. [ABSTRACT FROM AUTHOR]

Retrospective analysis of the contemporary colonial and scientific records of a major explosive eruption of the Soufrière of St Vincent from 1902 to 1903 reveals how this significant and prolonged event presented challenges to the authorities charged with managing the crisis and its aftermath. In a small-island setting vulnerable to multiple hazards, the spatial footprint of the volcanic hazard and the nature and intensity of the hazard effects were rather different to those of other recurrent hazards such as hurricanes. The eruption affected the same parts of the island that had been impacted by prior explosive eruptions in 1718 and 1812, and hurricanes in 1831 and 1898, with consequences that disproportionately affected those working in and around the large sugar estates. The official response to the eruption, both in terms of short-term relief and remediation, was significantly accelerated by the existence of mature plans for land-reform following the collapse of the sugar market, and ongoing plans for rebuilding in the aftermath of the destructive hurricane of 1898. The picture that this analysis helps to illuminate provides insights both into the nature of the particular eruptive episode, and the human and social response to that episode. This not only informs discussion and planning for future explosive eruptions on St Vincent, but provides important empirical evidence for building effective responses in similar multihazard contexts. [ABSTRACT FROM AUTHOR]

OBJECTIVE To compare the results of abdominal CT with exploratory laparotomy in the dog. ANIMALS 100 client-owned dogs from 1 academic institution. METHODS Medical records were searched for dogs that had undergone a preoperative abdominal CT scan read by a board-certified veterinary radiologist followed by an exploratory laparotomy. CT and surgical reports were compared. RESULTS The overall agreement between abdominal CT scan and exploratory laparotomy in all cases was 97%. Overall, there was no evidence that proportion agreement differed on the basis of body condition score, time interval between CT and surgery, or oncologic versus nononcologic disease. CLINICAL RELEVANCE Abdominal CT scan read by a board-certified diplomate is a sensitive presurgical diagnostic tool for surgical abdominal disease in the dog. When performing a specific abdominal surgery, it is acceptable for the surgeon to fully explore the abdomen or forego it for a smaller approach to the organ of interest if an abdominal CT was performed prior. [ABSTRACT FROM AUTHOR]

The silicic peralkaline volcanoes of the East African Rift are some of the least studied volcanoes on Earth. Here we bring together new constraints from fieldwork, remote sensing, geochronology and geochemistry to present the first detailed account of the eruptive history of Aluto, a restless silicic volcano located in a densely populated section of the Main Ethiopian Rift. Prior to the growth of the Aluto volcanic complex (before 500 ka) the region was characterized by a significant period of fault development and mafic fissure eruptions. The earliest volcanism at Aluto built up a trachytic complex over 8 km in diameter. Aluto then underwent large-volume ignimbrite eruptions at 316 ± 19 ka and 306 ± 12 ka developing a ~ 42 km 2 collapse structure. After a hiatus of ~ 250 ka, a phase of post-caldera volcanism initiated at 55 ± 19 ka and the most recent eruption of Aluto has a radiocarbon age of 0.40 ± 0.05 cal. ka BP. During this post-caldera phase highly-evolved peralkaline rhyolite lavas, ignimbrites and pumice fall deposits have erupted from vents across the complex. Geochemical modelling is consistent with rhyolite genesis from protracted fractionation (> 80%) of basalt that is compositionally similar to rift-related basalts found east of the complex. Based on the style and volume of recent eruptions we suggest that silicic eruptions occur at an average rate of 1 per 1000 years, and that future eruptions of Aluto will involve explosive emplacement of localised pumice cones and effusive obsidian coulees of volumes in the range 1–100 × 10 6 m 3 . [ABSTRACT FROM AUTHOR]

In tectonic settings where decompression melting drives magmatism, there is compelling evidence that changes in ice loading or water loading across glacial-interglacial cycles modulate volcanic activity. In contrast, the response of subduction-related volcanoes remains unclear. A high-resolution postglacial eruption record from a large Chilean stratovolcano, Mocho-Choshuenco, provides new insight into the arc magmatic response to ice-load removal. Following deglaciation, we identify three distinct phases of activity characterized by different eruptive fluxes, sizes, and magma compositions. Phase 1 (13-8.2 ka) was dominated by large dacitic and rhyolitic explosive eruptions. During phase 2 (7.3-2.9 ka), eruptive fluxes were lower and dominated by moderate-scale basaltic andesite eruptions. Since 2.4 ka (phase 3), eruptive fluxes have been elevated and of more intermediate magmas. We suggest that this time-varying behavior reflects changes in magma storage time scales, modulated by the changing crustal stress field. During glaciation, magma stalls and differentiates to form large, evolved crustal reservoirs. Following glacial unloading, much of the stored magma erupts (phase 1). Subsequently, less-differentiated magma infiltrates the shallow crust (phase 2). As storage time scales increase, volcanism returns to more evolved compositions (phase 3). Data from other Chilean volcanoes show a similar tripartite pattern of evacuation, relaxation, and recovery, suggesting that this could be a general feature of previously glaciated arc volcanoes. [ABSTRACT FROM AUTHOR]

The article talks about the role of Professor Constance Blackwell in introducing the field of intellectual history. It states that historians who study history as science, have compared it to laboratory sciences such as physics and chemistry. Topics include applied humanism, observation of nature's experiments in historical natural sciences, and the book "History of Florence" by Niccolò Machiavelli.

Magma–ice–meltwater interactions produce diverse landforms and lithofacies, reflecting the multitude of factors that influence glaciovolcanism, including both magmatic (e.g., composition, eruption rate) and glacial (e.g., ice thickness, thermal regime) conditions. This is exemplified by the walls of the partly ice-filled summit caldera of Volcán Sollipulli, a stratovolcano in southern Chile, which include lithofacies from eruptions of a wide range of magma compositions beneath or in contact with ice. Here we analyse these lithofacies and hence propose new interpretations of the eruptive and glacial history of Sollipulli. The facies include a thick, laterally extensive sequence of fragmental glaciovolcanic deposits, comprising massive, mafic lava pillow-bearing hyaloclastite overlain by sills and then hyaloclastic debris flow deposits (similar to Dalsheidi-type sequences). The distribution and thickness of these units indicate an unusual abundance of magma–meltwater interaction for an arc stratovolcano in temperate latitudes, perhaps due to eruptions beneath a thick ice cap. Coherent lava coulées, domes, lobes, and stacks of basaltic andesite–trachydacite composition are present around the top of the caldera rim; these display morphologies and fracture patterns on caldera-facing margins that indicate that the caldera was filled with ice when these lavas were erupted. The lithofacies characterised in this study demonstrate the diversity of glaciovolcanism that is possible at arc stratovolcanoes capped by temperate ice or with ice-filled calderas, and the potential for uncertainties in inference of the palaeoenvironmental conditions of their emplacement. [ABSTRACT FROM AUTHOR]

The East African Rift (EAR) hosts the highest density of peralkaline volcanoes of any region globally, making it an ideal location to study the subaerial and magmatic processes of peralkaline volcanism. Corbetti Caldera is one such peralkaline centre found within the southern part of the Main Ethiopian Rift (MER), a segment of the EAR. Corbetti is actively deforming and has previously undergone large-scale Plinian eruptions. However, our broader understanding of Corbetti's evolution is limited. Here we present a detailed study of the pre-, syn-and post-caldera eruptive deposits and compile them into a composite stratigraphy of the volcanic sequence. We find evidence for multiple previously undocumented large-scale eruptions, including the deposition of two pre-caldera lithic lag breccias, and we identify three additional post-caldera obsidian lavas. We constrain the age of a young Tuff Cone, Biftu, which sits outside the caldera walls, to <7375 ± 54 cal BP through 14C dating of shells within an associated PDC deposit. The Wendo Koshe Cone, the most recent cone within the complex, is interpreted as the remains of two cones that opened in close proximity to each other and formed the vents for two pyroclastic eruptions: Bedded Pumice and Wendo Koshe Younger Pumice (WKYP). There is abundant evidence for the occurrence of pyroclastic density currents (PDC) within the caldera, usually associated with pumice cone-forming eruptions. These flow deposits rarely extend beyond the caldera walls. From our compiled stratigraphy, we estimate a recurrence rate of one eruption per 300–400 years over the last 2.3 ky. These findings are especially significant as Corbetti is earmarked for potential geothermal exploration, and an understanding of eruptive frequency and style provides vital context to assess the potential hazards associated with this future infrastructure. • We present a detailed composite stratigraphy of eruptive deposits from Corbetti Caldera, Ethiopia • Previously undocumented deposits are identified, indicating Corbetti commonly generates large-scale, dilute PDCs • The Wendo Koshe Cone comprises of two overlapping vents from which the Bedded Pumice and WKYP eruptions were sourced • The age of the Biftu Tuff Cone has been constrained to <7375 ± 54 cal BP • We estimate Corbetti has a recurrence rate of one eruption per 300–400 years over the last 2.3 ka [ABSTRACT FROM AUTHOR]

Abstract: Understanding the underlying structure of data from volcano monitoring is essential to identify precursors to changes in eruptive activity and to comprehend volcanic processes. However, effective analysis of longer-term trends in these signals is challenging as volcanic data are not necessarily statistically stationary or linear, particularly those from lava dome-forming volcanoes, which are commonly characterised by pulsatory eruptive activity. Here, we use detrended fluctuation analysis (DFA), a statistical technique previously applied to nonstationary data, to identify long-range (slowly decaying, e.g. power-law) correlations in a number of time-series of volcano seismicity recorded during the recent dome-forming eruptions of Volcán de Colima, Mexico, and Soufrière Hills Volcano, Montserrat. For all the time-series analysed, correlation strength varies through time and/or on different timescales; in some cases, this variation is periodic, seasonal, and/or related to activity. These results may provide new insights into eruptive processes and possibly further constrain the generation mechanisms of a number of the volcano-seismic event classes analysed. Furthermore, the correlation properties of real-time seismic measurements are shown (retrospectively) to contain information valuable to real-time volcano monitoring that is not identifiable by conventional analysis techniques. This study therefore demonstrates that long-range correlation analysis may be useful for extracting additional information from monitoring data at dome-forming or similar volcanoes. [Copyright &y& Elsevier]

Abstract: Several lines of evidence have previously been used to suggest that ice retreat after the last glacial maximum (LGM) resulted in regionally-increased levels of volcanic activity. It has been proposed that this increase in volcanism was globally significant, forming a substantial component of the post-glacial rise in atmospheric CO2, and thereby contributing to climatic warming. However, as yet there has been no detailed investigation of activity in glaciated volcanic arcs following the LGM. Arc volcanism accounts for 90% of present-day subaerial volcanic eruptions. It is therefore important to constrain the impact of deglaciation on arc volcanoes, to understand fully the nature and magnitude of global-scale relationships between volcanism and glaciation. The first part of this paper examines the post-glacial explosive eruption history of the Andean southern volcanic zone (SVZ), a typical arc system, with additional data from the Kamchatka and Cascade arcs. In all cases, eruption rates in the early post-glacial period do not exceed those at later times at a statistically significant level. In part, the recognition and quantification of what may be small (i.e. less than a factor of two) increases in eruption rate is hindered by the size of our datasets. These datasets are limited to eruptions larger than 0.1km3, because deviations from power-law magnitude–frequency relationships indicate strong relative under-sampling at smaller eruption volumes. In the southern SVZ, where ice unloading was greatest, eruption frequency in the early post-glacial period is approximately twice that of the mid post-glacial period (although frequency increases again in the late post-glacial). A comparable pattern occurs in Kamchatka, but is not observed in the Cascade arc. The early post-glacial period also coincides with a small number of very large explosive eruptions from the most active volcanoes in the southern and central SVZ, consistent with enhanced ponding of magma during glaciation and release upon deglaciation. In comparison to non-arc settings, evidence of post-glacial increases in rates of arc volcanism is weak, and there is no need to invoke significantly increased melt production upon ice unloading, as occurred in areas such as Iceland. Non-arc volcanoes may therefore account for a relatively higher proportion of global volcanic emissions in the early post-glacial period than is suggested by the relative contributions of arc and non-arc settings at the present day. The second part of this paper critically examines global eruption records, in an effort to constrain global-scale changes in volcanic output since the LGM. Accurate interpretation of these records relies on correcting both temporal and spatial variability in eruption recording. In particular, very low recording rates, which also vary spatially by over two orders of magnitude, prevent precise, and possibly even accurate, quantitative analysis. For example, if we assume record completeness for the past century, the number of known eruptions (volcanic explosivity index≥2) from some low-latitude regions, such as Indonesia, is approximately 1 in 20,000 (0.005%) for the period 5–20ka. There is a need for more regional-scale studies of past volcanism in such regions, where current data are extremely sparse. We attempt to correct for recording biases, and suggest a maximum two-fold (but potentially much less) increase in global eruption rates, relative to the present day, between 13 and 7ka. Although volcanism may have been an important source of CO2 in the early Holocene, it is unlikely to have been a dominant control on changes in atmospheric CO2 after the LGM. [Copyright &y& Elsevier]

Abstract: One of the longest continuous periods of dome-forming activity on record is the ongoing eruption of Santiaguito, Guatemala. Dome-building began in 1922, within the crater formed during the cataclysmic 1902 eruption of Santa María, and continues today. The earliest erupted Santiaguito lavas are chemically and mineralogically identical to the dacite pumice erupted in 1902. The erupted magma has become progressively less evolved over time, with a decrease in whole rock SiO2 from ~66 to ~62wt.% from 1922 to 2002. New geochemical data from Santiaguito are consistent with a model of magma being extracted progressively from a chemically-stratified lower crustal (~12 to ~25km) storage zone thought to have formed during the ~25ka of quiescence that preceded the 1902 eruption. The bimodal distribution of plagioclase phenocryst core compositions in early Santiaguito lavas suggests that they were strongly influenced by magma mixing in addition to fractional crystallization. However, lavas erupted since the 1940s show a unimodal distribution, suggesting a diminishing role for mixing within the Santiaguito system. Trace element data suggest that the decrease in silica content over time is best explained by a decrease in the extent of fractional crystallization of ~15% over the 80years covered by our sample set. [Copyright &y& Elsevier]

Abstract: Late Glacial and Holocene soils and sediments in southern Chile contain an important record of explosive volcanic activity since the end of the last glaciation, and have considerable potential for the development of a regional tephrostratigraphical framework. This paper reports the discovery of several new tephra deposits from the Hualaihue region (∼42° S) of southern Chile. Eruption sizes, constrained from field observations, and ages, constrained by 25 new radiocarbon dates, show that the volcanoes of the Hualaihue peninsula have had relatively few explosive, tephra-generating eruptions during the Holocene. An eruption of Apagado deposited ∼1 km3 of bedded basaltic scoria at ∼2.6 calibrated (cal) ka BP, and Hornopirén produced a similar, but volumetrically-smaller unit at ∼5.7 cal ka BP. Activity at Yate over the same time period has been predominantly characterised by lava production, although small explosive eruptions, the products of which span a range of compositions, have also occurred, including one at ∼0.9 cal ka BP. The northern part of the regional tephra sequence is dominated by andesitic pumice fall deposits derived from Calbuco volcano. These include deposits from several eruptions during a 3500-year-long period at the start of the Holocene, as well as two large explosive eruptions in the past 2000 years. A distinctive rhyolitic tephra layer that is interbedded with the locally derived tephra sequence is the Cha1 unit, from Chaitén volcano, 108 km south of Hornopirén. This rhyolitic pumice deposit, dated at ∼9.75 cal ka BP, is the largest volumetrically of those described here, with a volume of 3.5 km3. This new tephrostratigraphy covers a region whose volcanic history was previously very little known, and contributes to a regional record of large explosive eruptions that now spans a 500 km-long segment of the southern Andean arc, between Calbuco and Hudson volcanoes. [Copyright &y& Elsevier]

Abstract: Monazite growth and composition has been modeled in the system K2O–Na2O–CaO–MnO–MgO–FeO–Al2O3–SiO2–H2O–Y2O3–Ce2O3–P2O5–F and a pseudosection is presented that is contoured for monazite modal amount and YPO4 composition, garnet amount and YAG composition, and xenotime amount. Monazite amount and composition is strongly controlled by the presence of xenotime and when xenotime is absent, by the growth or consumption of garnet. Monazite grows continuously in the subsolidus region over most reasonable metamorphic P–T paths with YPO4 content generally increasing with increasing temperature, especially where xenotime is present. When melt is present, monazite is consumed with increasing melting and, in the absence of xenotime, decreases in YPO4 content. Two prograde forward models are presented to illustrate the effect of garnet fractional crystallization on the results. When xenotime is present and the modal amount of garnet is low (e.g., at low pressure), fractional crystallization has little effect on phase amount or composition. Where xenotime is absent and garnet is more abundant (e.g., at intermediate to high pressure), garnet fractionation dominates both monazite growth history and composition. In particular, YPO4 content of monazite drops to nearly zero at intermediate grades in a rock in which garnet has sequestered the Y as YAG component. This Y may be released by diffusion at higher temperature and promote monazite growth with a higher YPO4. Therefore, the growth history of monazite as inferred from YPO4 zoning may be quite complex and reflect different reactions and processes, even in a simple bulk composition. [Copyright &y& Elsevier]

This article discusses the development of scientific methodologies during the Renaissance period. It tackles the idea of art as science, the idea of history as science, the concept of Renaissance humanism, the insights of Renaissance art historian Edgar Wind on aesthetics, and the association between history and natural science.

Abstract: Instrumental and spectral characteristics germane to chemical dating of monazite have been tested using the Cameca SX-100 at Rensselaer Polytechnic Institute. Statistical analysis demonstrates that, for trace element analysis, equal counting time on peak and background is required for optimal statistical precision, thus rendering impractical the procedure of fitting the entire spectrum to obtain background values. Energy shifts require shifting the detector voltage window between peak and background positions, and it is concluded that the differential auto PHA mode works optimally for this. Analyses of Pb-free phosphates, silicates, and oxides are used to measure spectral interferences with the PbMα peak and background positions. Backgrounds were modeled using both linear and exponential fits. It was found that the difference in background counts using the two fits varies with each of the five spectrometers examined, and that the high-pressure (3bar) detectors show larger differences in exponential vs. linear peak-minus-background (P-B) values than the low-pressure (1bar) detectors. In addition, every spectrometer requires a unique correction for every major element in monazite. An analytical protocol is presented that incorporates these results. This protocol was applied to several monazite standards to determine inter-spectrometer variability, and spectrometer reproducibility from session to session. It was found that the difference in composition (and age) between spectrometers on identical spots exceeds the 2 sigma standard error of the mean of composition (or age) on either spectrometer. This means that (a) additional sources of error beyond the counting statistics exist between spectrometers; (b) the precision of microprobe ages cannot be continuously improved by additional counting; and (c) the minimum realistic precision is on the order of ±2–3% for monazites with around 1500–2000ppm total Pb, or an additional absolute uncertainty of 20–50ppm Pb. [Copyright &y& Elsevier]

At Mount Etna, Italy, vigorous gas-rich eruptions in A.D. 2001, 2002, and 2003 were followed by gas-poor eruptions in 2004, 2006, and 2007. Analyses of volatile (CO2, H2O, S, Cl, F), semivolatile (Cu), and involatile (Nb, La) elements trapped in olivine-hosted melt inclusions from these latest eruptions reveal the effects of the sustained interaction between a percolating gas phase and the stored magma. Melt inclusion compositions indicate that magmas erupted from 2004 to 2007 were residual from the 2001-2003 eruptions, and show significant evolution in the volatile content of the melt. These melt inclusion observations, and variations in the C/S of volcanic gases, can be accounted for if melts reequilibrated with CO2-rich gases during storage and prior to entrapment as melt inclusions. Sustained gas percolation caused loss of water and enhancement of CO2 in the evolving melt and may strongly influence the behavior of Cu, which potentially partitions into the gas phase. Vapor-melt interactions during magma storage are important controls on magma evolution at persistently degassing volcanoes. [ABSTRACT FROM AUTHOR]

Abstract: Seismic activity has been postulated as a trigger of volcanic eruption on a range of timescales, but demonstrating the occurrence of triggered eruptions on timescales beyond a few days has proven difficult using global datasets. Here, we use the historic earthquake and eruption records of Chile and the Andean southern volcanic zone to investigate eruption rates following large earthquakes. We show a significant increase in eruption rate following earthquakes of M W >8, notably in 1906 and 1960, with similar occurrences further back in the record. Eruption rates are enhanced above background levels for ~12 months following the 1906 and 1960 earthquakes, with the onset of 3–4 eruptions estimated to have been seismically influenced in each instance. Eruption locations suggest that these effects occur from the near-field to distances of ~500 km or more beyond the limits of the earthquake rupture zone. This suggests that both dynamic and static stresses associated with large earthquakes are important in eruption-triggering processes and have the potential to initiate volcanic eruption in arc settings over timescales of several months. [Copyright &y& Elsevier]

Umbilical cord matrix stem (UCMS) cells that were engineered to express interferon-beta (IFN-β) were transplanted weekly for three weeks into MDA 231 breast cancer xenografts bearing SCID mice in combination with 5-fluorouracil (5-FU). The UCMS cells were found within lung tumors but not in other tissues. Although both treatments significantly reduced MDA 231 tumor area in the SCID mouse lungs, the combined treatment resulted in a greater reduction in tumor area than by either treatment used alone. These results indicate that a combination treatment of UCMS-IFN-β cells and 5-FU is a potentially effective therapeutic procedure for breast cancer. [ABSTRACT FROM AUTHOR]

C. P. Snow's 'two cultures' distinction between scientific and humanistic thought is perennial. It may be said to correspond to empirical and metaphorical bents in human nature. Since antiquity, attempts have been made by some to bridge the gap. The natural bridge of scientific (in the broad sense) scholarship has been largely overlooked, but the development in the West of philological and historical methods by fifteenth and early sixteenth century humanists (in the technical sense) exhibits numerous criteria and examples of a scientific approach to the world around us, as does such scholarship today. [ABSTRACT FROM AUTHOR]

Abstract: A trachytic volcanic ash layer is widely distributed across south-western Russia, where it is found both in well-characterised archaeological contexts close to the Don River (the Paleolithic sites of Kostenki-Borschevo (51.4°N, 39.0°E), and in undisturbed geological contexts. This ash layer has all of the characteristics of a distal tephra fall deposit: it is fine grained and unimodal with a grain size of 60–170μm, dominated by strongly elongate glass shard fragments. Chemical analysis confirms that this ash layer is a distal equivalent of the deposits of the ca 39.3ka Campanian Ignimbrite eruption of the Phlegrean Fields, Italy, and correlates with the widely recognised Y5 ash layer in marine cores in the south-eastern Mediterranean. This work shows that ash particles can be dispersed over considerable distances (>2500km) and areas (>1.5–3×106 km2) during large-magnitude explosive eruptions. The volume of the products associated with this event (31–50km3 of magma erupted as fallout tephra, and a total volume of 105–210km3 of magma, or 2.5–5×1014 kg) confirms the Campanian Ignimbrite/Y5 eruption as the most significant known volcanic eruption in Europe of the past 100ka. This correlation places tight constraints on the absolute ages of a number of important archaeological horizons in southern Russia. [Copyright &y& Elsevier]

Abstract: The dacitic lava flows of Nea Kameni, Santorini, Greece, contain a variety of partially-crystalline mafic enclaves. Each enclave type is derived from the break-up of a layer of replenishing magma, emplaced in the dacite chamber prior to eruption. Crystallisation-induced vesiculation of this layer, driven by the temperature contrast between the two magmas, was sufficient to drive upwelling and overturn of the layer, resulting in the formation of mafic enclaves within the host. The replenishing magmas are preserved as enclaves due to the presence of a plagioclase crystal framework. Spatial distribution pattern (SDP) analysis and melting experiments demonstrate that the plagioclase crystallinity and crystal aspect ratios observed in the Kameni enclaves are sufficient to form a touching framework of crystals. Observations on the coherence of the framework during exsolution of volatiles and enclave transport suggest that the morphology of the dominant framework-forming phase places a significant control on the strength and viscosity of the crystal framework, which in turn determines the extent to which the replenishing magmas will fragment and mix with the dacite host. Frameworks composed of high-aspect ratio crystals are weak, and respond to rapid vesicle expansion in a brittle manner. The replenishing magma then disaggregates to become a source of crystals dispersed throughout the host magma. In contrast, low-aspect ratio crystals form strong crystal frameworks that are more resistant to rapid vesicle expansion, resulting in preservation of the replenishing magma as vesicular enclaves. [Copyright &y& Elsevier]

Abstract: Analysis of monazite-bearing lithologies from the Precambrian Honey Brook Upland (HBU) and overlying metasedimentary Paleozoic Chester Valley Sequence (CVS) (SE PA, USA) reveals overprinting of primary major and accessory phase parageneses by texturally and compositionally disparate secondary accessory phase parageneses. Two-pyroxene temperatures of 915–945 °C for reconstituted pyroxene reflect emplacement temperatures of felsic plutonic rocks (opdalite, charnockite) prior to Mesoproterozoic metamorphism. Monazite in metavolcanic felsic gneiss yields three age domains at 1009±4 Ma (2 s.e.), 965±6, and 876±10 Ma. The first two domains record metamorphism of the HBU after anorthosite intrusion; peak monazite–xenotime temperatures for the monazite core domain are ∼700 °C, and high Th/U values in the second (overgrowth) age domain likely reflect a second high-T monazite growth episode. Formation of cummingtonite coronas on orthopyroxene in opdalite constrains maximum ∼1010 Ma metamorphic temperatures in the “granulite-facies” terrane to 730–740 °C. Evidence of increased Cl fluid activity in the ∼965 Ma metamorphism includes higher Cl content of matrix apatite relative to garnet-included apatite (metavolcanics), and Cl-bearing K-hornblende succeeding cummingtonite in coronal overgrowths (opdalite). Extreme monazite Th/U values (75–250) in the rim domain suggest growth during low-T hydrothermal alteration. In the opdalite, secondary singe-grain monazite and monazite+xenotime metasomites in apatite yield ages of 714±24 and 586±88 Ma, temperatures of 325–425 °C, and are interpreted to reflect thermal disturbances associated with late Proterozoic plutonic and volcanic activity in the Upland. This thermal disturbance may be recorded by Rb–Sr age of 567 Ma for biotite from a HBU gneiss. Monazite age domains in metaquartzite (378±28, 272±44 Ma) suggest that low-grade metamorphism (260–320 °C, Mnz–Xno thermometry) of the CVS is not a result of Taconian orogenesis. [Copyright &y& Elsevier]

Abstract: A new technique to analyze aqueous samples for nanograms per liter levels of volatile and semivolatile compounds using microextraction and thermal desorption into a gas chromatograph/ion trap mass spectrometer (GC/MS) is described. This method is inherently sensitive (50mL of aqueous sample is extracted prior to each desorption), uses no solvents, and detects volatiles and semivolatiles in the same analysis. Aqueous standards and environmental samples are pumped through a length of porous-layer open-tubular capillary column, which is then thermally desorbed onto a 30m×0.25mm i.d. analytical column interfaced to an ion trap mass spectrometer for subsequent separation and detection. Sharp chromatographic peaks and reproducible retention times (RT) were observed. Replicate injections of surrogates (n =6) averaged 32.6% R.S.D. Analysis of domestic tap water detected 55 analytes, some at the low-nanograms per liter level, and detected 3 halogenated ethenes, not previously reported in drinking water. Analysis of an aqueous sample from a municipal ground water source detected the presence of numerous semivolatile compounds at trace-levels. [Copyright &y& Elsevier]

Al2SiO5 reaction textures in aluminous schist and quartzite of the northern Picuris range, north-central New Mexico, record a paragenetic sequence of kyanite to sillimanite to andalusite, consistent with a clockwise P–T loop, with minor decompression near the Al2SiO5 triple-point. Peak metamorphic temperatures are estimated at 510–525°C, at 4·0–4·2 kbar. Kyanite and fibrolite are strongly deformed; some prismatic sillimanite, and all andalusite are relatively undeformed. Monazite occurs as inclusions within kyanite, mats of sillimanite and centimetre-scale porphyroblasts of andalusite, and is typically aligned subparallel to the dominant regional foliation (S0/S1 or S2) and extension lineation (L1). Back-scatter electron images and X-ray maps of monazite reveal distinct core, intermediate and rim compositional domains. Monazite–xenotime thermometry from the intermediate and rim domains yields temperatures of 405–470°C (±50°C) and 500–520°C (±50°C), respectively, consistent with the prograde to peak metamorphic growth of monazite. In situ, ion microprobe analyses from five monazites yield an upper intercept age of 1417 ± 9 Ma. Near-concordant to concordant analyses yield 207Pb–206Pb ages from 1434 ± 12 Ma (core) to 1390 ± 20 Ma (rim). We find no evidence of older regional metamorphism related to the ∼1650 Ma Mazatzal Orogeny. [ABSTRACT FROM AUTHOR]

Four distinct generations of monazite growth have been identified in samples from theth Chesham Pond Nappe, and three (monazite compositional domains 2, 3, and 4) have been correlated with both temperature and mineral assemblage. Domain 1 cores were interpreted previously to be detrital relics or vestiges of an earlier Acadian metamorphism. The four monazite domains have been dated by in situ isotope and chemical methods; the following are chemical ages of each domain (weighted average ±2 standard errors of the mean): 400 ± 10 Ma (domain 1); 381 ± 8 Ma (domain 2); 372 ± 6 Ma (domain 3); 352 ± 14 Ma (domain 4). Heating and cooling rates derived from combining monazite ages, monazite thermometry, and 40Ar/39Ar closure temperatures are approximately 10-15 °C/m.y. for heating from 470 to 740 °C, approximately 8 °C/m.y. for cooling from 740 to 375 °C, and approximately 1-2 °C/m.y for cooling from 375 to 150 °C. Temperature-time paths calculated with monazite ages and monazite thermometry indicate that (1) plutonism at ca. 400 Ma was the likely heat source for the formation of monazite domain 1 and (2) monazite domains 2-4 were produced during a regional low-pressure, high-temperature metamorphism active between 380-350 Ma. The regional metamorphism is ascribed to lithospheric mantle delamination, followed by asthenospheric mantle upwelling, which heated a wide area of the Merrimack basin (southwestern New Hampshire, central Massachusetts, central Connecticut) to temperatures in excess of 725 °C. Monazite ages in the Chesham Pond Nappe and adjacent structural units to the west constrain the commencement of nappe overthrusting to roughly 355 Ma. [ABSTRACT FROM AUTHOR]

We examine the factors controlling accuracy and precision of monazite microprobe ages, using a JEOL 733 Superprobe equipped with 4 PET crystals, and both 1-arm gas flow Ar X-ray detectors and sealed Xe X-ray detectors. Multiple PET crystals allow for simultaneous determination of Pb concentration on up to 3 detectors, and the effects of different detector gases on spectral form can be addressed. Numerous factors in the X-ray production, detection, and counting sequence affect spectral form, including: choice of accelerating voltage, changes in d-spacing of the diffraction crystal, use of X-ray collimation slits, and type of detector gas. The energy difference between ArKα X-rays and XeLα X-rays results in, for 1-arm Ar detectors, escape peaks of second-order LREE L line X-rays that cannot be filtered using differential mode PHA. The second-order LREE energies are passed to the counter and produce, for a 140 mm Rowland circle, several problematic interferences in the Pb region of a monazite wavelength-dispersive (WD) spectrum. WD monazite spectra produced with Xe detectors are free from second-order LREE interferences in the Pb region; escape peaks of the second-order LREE are filterable with differential mode PHA if Xe detectors are employed. Silicon, Ca, Y, Ce, P, Th, U, and Pb (2 spectrometers) are measured as part of the monazite microprobe dating protocol; ±2σ variations in elements fixed for ZAF corrections do not affect the age outside of analytical uncertainty. ThMα, UMβ, and PbMα are the analyzed lines of the age components. Corrections for interference of ThMζ1,2 and YLγ2,3 on PbMα are significant, but can be done precisely, and reduce the precision of the Mα analysis by a trivially small amount. ThMγ, M3-N4, and M5-P3 interferences on UMβ can be corrected, as well, but ThM5 and M4 absorption edges in high-Th samples make estimation of UMβ background... [ABSTRACT FROM AUTHOR]

Hot volcanic vents promote the thermal fixation of atmospheric N[sub 2] into biologically available forms. The importance of this process for the global nitrogen cycle is poorly understood. At Masaya volcano, Nicaragua, NO and NO[sub 2] are intimately associated with volcanic aerosol, such that NO[sub x] levels reach as much as an order of magnitude above local background. In-plume HNO[sub 3] concentrations are elevated above background to an even greater extent (≤50 µmol·m[sup -3]). We estimate the production efficiency of fixed nitrogen at hot vents to be ∼3 × 10[sup -8] mol·J[sup -1], implying present-day global production of ∼10[sup 9] mol of fixed N per year. Although conversion efficiency would have been lower in a preoxygenated atmosphere, we suggest that subaerial volcanoes potentially constituted an importance source of fixed nitrogen in the early Earth, producing as much as ∼10[sup 11] mol·yr[sup -1] of fixed N during major episodes of volcanism. These fluxes are comparable to estimated nitrogen-fixation rates in the prebiotic Earth from other major sources such as bolide impacts and thunderstorm and volcanic lightning. [ABSTRACT FROM AUTHOR]

Mercury is a highly volatile, bioaccumulating toxic trace metal with a long (∼1 yr) atmospheric residence time. Hg is strongly enriched in volcanic emanations, and volcanoes are the only natural sources of direct Hg emission to the free troposphere and stratosphere. However, there is considerable uncertainty over the annual emission rate of mercury from volcanoes. Previous estimates, based on limited measurements from volcanic plumes, span three orders of magnitude (∼100–103 Mg Hg/yr), or from <1% to ∼50% of total natural Hg emissions.Here we critically evaluate published data from volcanic plumes, and combine this with information from natural archives to show unequivocally the significance of volcanoes for the global biogeochemical mercury cycle. ‘Low’ global volcanic flux estimates (<∼50 Mg/yr) are based on the inappropriate extrapolation of data from low-temperature fumarolic degassing at non-erupting volcanoes to the high-temperature emissions from active volcanoes. Based on data from active volcanoes, we estimate that the time-averaged volcanic Hg emission is ∼700 Mg/yr, or 20–40% of total natural emissions. Continuous degassing accounts for only ∼10% of this flux, while 75% of volcanic Hg is released during ‘smaller’ sporadic eruptions (<10–102 Mg/event). Rare, large (>103 Mg) explosive eruptions overwhelm the total atmospheric burden several times per century, and account for ∼15% of total volcanic Hg emissions. [Copyright &y& Elsevier]

Presents information on a study which modeled growth and consumption of accessory phases with the method of differential thermodynamics and correlated with specific major-phase reactions. Geological setting; Major phase reaction history; Generation of accessory phases in the samples.

Prograde suites of pelitic rocks were examined with electron microprobe and laser ablation inductively coupled plasma mass spectrometry to determine the systematics of element partitioning between coexisting monazite, xenotime, and garnet. Monazite grains that grew in equilibrium with xenotime are enriched in Y and Dy compared with monazite that grew in xenotime-absent assemblages. Y and heavy rare earth element contents of monazite coexisting with xenotime increase with rising temperature. Monazite–xenotime Y–Gd and Y–Dy partitioning is systematic within a metamorphic grade, and increases slightly with increasing metamorphic grade, suggesting that monazite–xenotime pairs approached partitioning equilibrium. Garnet and monazite in both xenotime-bearing and xenotime-absent assemblages show a strong ( R2 = 0·94) systematic relationship between inverse temperature and ln(KEq) for the net-transfer equilibrium YAG + OH-Ap + (25/4)Qtz = (5/4)Grs + (5/4)An + 3YPO4-Mnz + 1/2H2O, suggesting that garnet and monazite crystallized in compositional equilibrium. The following temperature–KEq relationship for the equilibrium above has been derived: [ABSTRACT FROM PUBLISHER]

New geochemical data are presented from prehistoric and historical eruptive products of the Lamongan volcanic field (LVF), East Java; a region of the Sunda arc covering ∼260 km2 and containing ∼90 eruptive vents plus the historically active Lamongan volcano. LVF lavas include medium-K basalts and basaltic andesites from historical eruptions of Lamongan and prehistoric eruptions in the eastern LVF, along with a high-K suite represented by prehistoric deposits in the western LVF. Although lacking some of the characteristics of truly primary basalts, the least evolved lavas identified in the LVF have some of the lowest SiO2 contents (∼43 wt % SiO2) yet reported in Sunda arc volcanic rocks. Mass balance considerations indicate that two chemically distinct LVF magmas may be parental to suites currently being erupted from the neighbouring volcanoes, Semeru and Bromo. Lamongan’s historical lavas can be related to the medium-K andesitic products of Semeru by fractional crystallization, despite the former’s location at the same distance from the trench as Bromo, a high-K volcano. Extensional tectonics, possibly related to arc segmentation in the region of the LVF, creating conditions that promote the rapid ascent of parental magmas, is probably responsible for this and several other features of the complex. [ABSTRACT FROM PUBLISHER]

Examines the use of observation, depiction and description to illustrate art as a form of science. Observation and description in artist Leonardo da Vinci's methods; Active observation and description used by scientist Robert Hooke in his studies; Refining communication as a part of science; Visual description in 16th century natural history.

Examines air and water pollutant emissions from two outboard engines operating on reformulated gasoline containing methyl tertiary butyl ether (MTBE). Higher levels of toxic organic and particulate matter emissions from the two-stroke engine; Finding that aqueous emission rates and atmospheric emission rates tend to increase with decreasing engine load.

Presents experiments conducted to predict the sizes and repose times of extreme volcanic eruptions. Detailed inforamtion on large-magnitude volcanic events; Reference to the rarity of these volcanic events; Statistical inforamtion on these volcanic eruptions; Reference to data for volcanic eruptions since Anno Domini (A.D.) 1815; Information on activity of the Taupo Volcano in New Zealand.

Presents the findings of a study that analyzed soil extracts from five Superfund Contract Laboratory Program laboratories for organochlorine pesticides using a gas chromatographic separation with ion trap mass spectrometric detection in electron impact (GC/EIMS) and tandem mass spectrometry (GC/MS/MS) modes. Details on the standard CLP dual-column gas chromatography electron capture detection pesticide method.

Reports on the comparison of analysis of lead and cadmium in soil using the laboratory techniques atomic absorption spectroscopy (AAS), X-ray fluorescence (XRF) spectroscopy, inductively coupled plasma-atomic emission spectroscopy (ICP-AES), and potentiometric stripping analysis (PSA). Magnitudes of uncertainty in the measurements; Correlations between data.

The article presents a case study of a 48-year-old man presented with a 2-month history of a red scrotum. Topics discussed include redness initially started along his right inguinal fold and then extended to his perineum and scrotum; diagnosis of red scrotum syndrome; and burning, pruritus, and/or pain of the genitals.

The timing and processes that govern the end of volcanic eruptions are not yet fully understood, and there currently exists no systematic definition for the end of a volcanic eruption. Currently, end of eruption is established either by generic criteria (typically 90 days after the end of visual signals of eruption) or criteria specific to a given volcano. We explore the application of supervised machine learning classification methods: Support Vector Machine, Logistic Regression, Random Forest and Gaussian Process Classifiers and define a decisiveness index D to evaluate the consistency of the classifications obtained by these models. We apply these methods to seismic time series from two volcanoes chosen because they display contrasting styles of eruption: Telica (Nicaragua) and Nevado del Ruiz (Colombia). We find that, for both volcanic systems, the end-date we obtain by classification of seismic data is 2–4 months later than end-dates defined by the last occurrence of visual eruption (such as ash emission). This finding is in agreement with previous, general definitions of eruption end and is consistent across models. Our classifications have a higher correspondence of eruptive activity with visual activity than with database records of eruption start and end. We analyze the relative importance of the different features of seismic activity used in our models (e.g. peak event amplitude, daily event counts) and find little consistency between the two volcanic systems in terms of the most important features which determine whether activity is eruptive or non-eruptive. These initial results look promising and our approach may offer a robust tool to help determine when an eruption has ended in the absence of visual confirmation. • Machine learning classification applied to time series derived from seismic data. • End-dates obtained by classification are 2–4 months later than the last evidence of visual eruption. • These end-dates are in agreement with previous, non-physical definitions of eruption end. [ABSTRACT FROM AUTHOR]

Understanding the timing of critical changes in volcanic systems, such as the beginning and end of eruptive behavior, is a key goal of volcanic monitoring. Traditional approaches to forecasting these changes have used models motivated by the underlying physics of eruption onset, which assume that geophysical precursors will consistently display similar patterns prior to transition in volcanic state. We present a machine learning classification approach for detecting significant changes in patterns of volcanic activity, potentially signaling transitions during the onset or end of volcanic activity, which does not require a model of the physical processes underlying critical changes. We apply novelty detection, where models are trained only on data prior to eruption, to the precursory unrest at Augustine Volcano, Alaska in 2005. This approach looks promising for geophysically monitored volcanic systems which have been in repose for some time, as no eruptive data is required for model training. We compare novelty detection results with multi‐class classification, where models are trained on examples of both non‐eruptive and eruptive data. We contextualize the results of these classification models using constraints from petrological, satellite and visual observations from the 2006 eruption of Augustine Volcano. The transition from non‐eruptive to eruptive behavior we identify in mid‐November 2005 is in agreement with previous estimates of the initiation of dike intrusion prior to the 2006 eruption. We find that models which include multiple types of data (seismic, deformation, and gas emissions) can better distinguish between non‐eruptive and eruptive data than models formulated on single data types. Plain Language Summary: Identifying the onset of volcanic activity is a central goal of volcanology. We apply machine learning approaches to seismic, gas and geodetic data in order to classify eruptive and non‐eruptive activity. We consider models trained on only pre‐eruptive data, and models trained on both non‐eruptive and eruptive data. Our models begin to identify eruptive behavior in mid‐November 2005, which coincides with previous estimates of the beginning of transport of magma to the surface. We compare the models constructed using all data types to those made with each data type individually. We find that models which include multiple types of data are better at identifying non‐eruptive and eruptive activity. Key Points: Application of one‐class and multi‐class machine learning classification to seismic, gas and geodetic time series from the 2006 eruption of Augustine Volcano, AlaskaWe identify a transition from non‐eruptive to eruptive activity in November 2005, coinciding with previous estimates of the initiation of dike intrusionModels formulated using all datasets (seismic, gas, and geodetic) distinguish between non‐eruptive and eruptive data better than models trained on a single data type alone [ABSTRACT FROM AUTHOR]