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Stromboli volcano represents an archetypical long-lasting open system volcano with a persistent mild explosive activity. This “ordinary” activity is sometimes interrupted by other kinds of activities such as: (i) major effusive eruptions, (ii) short-lived lava overflows, (iii) major explosions and (iv) paroxysmal explosions. Here, we present more than two decades of satellite-derived thermal data acquired over Stromboli by the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Visible Infrared Imaging Radiometer Suites between 2000 and 2022. We focused on the results obtained by comparing the Volcanic Radiative Power (VRP, Watt) retrieved from satellite with the catalogue of not-ordinary events that occurred in the same period. As a results, our analysis reveal that each type of activity is characterized by specific thermal patterns during the pre-, sin- and post-event phases. These results suggest that the space-based data may concur to better understand the processes acting on the Stromboli plumbing system and the role of the shallow magma column in driving ordinary and “not-ordinary” activity., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

The 2021 hybrid Tajogaite eruption of Cumbre Vieja (La Palma) was mainly effusive, with >70% of volume erupted as lava and simultaneous explosive activity with variable eruptive styles (e.g., Strombolian, violent Strombolian, lava fountaining, ash-poor gas puffing) depositing a widespread tephra blanket. Tephra dispersal and grainsize features indicate violent Strombolian dynamics when field-based classification schemes are used. Statistical analyses of pulsatory activity indicate short-time fluctuations amongst the observed multiple eruptive styles, suggesting rapid gas segregation and high magma ascent rate modulating magma fragmentation and conduit dynamics distributed at the different vents. Pulsatory activity and variable eruptive style affected tephra sedimentation causing unsteady tephra ground accumulation across time. Various sedimentation processes were observed, including particle aggregation (especially in case of rainy atmospheric conditions) and different types of sedimentation features (e.g., lapilli waves, ash fingers). The tephra blanket, with a volume of ~2×107 m3, was mostly dispersed NE-SW due to the complex regional and local wind patterns and was subdivided into three units and eleven layers that well correlate at different distances from the vent and agree with both seismic tremor data and lava emission rates. Grainsize distributions at individual locations are unimodal, with Mdf increasing and sorting decreasing with distance from the vents. Total grainsize distributions of selected layers, units, and the whole tephra blanket are unimodal with Mdphi values between -0.5 and 1.4 phi (1.4-0.4 mm). Evidence of the Tajogaite eruption dynamics highlight the challenges of risk and crisis management associated with long-lasting basaltic pulsatory hybrid eruptions., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

We used a large set of satellite- (visible, infrared, and radar images from Planetscope, MODIS, VIIRS, Sentinel2, Landsat 8, and Sentinel 1) and ground-based data (optical images, SO2 flux, shallow seismicity) to describe and characterize the activity of the Sabancaya volcano during the unrest and eruption phases that occurred between 2012 and 2020. The unrest phase (2012–2016) was characterized by increasing gas and thermal flux, sourced by a convective magma column rising along with the remnants of a buried plug still permeable to fluid flow. Conversely, a new conduit, adjacent to the previous one, fed the eruptive phase (2016–2020) which was instead characterized by a discontinuous extrusive activity, with phases of dome growth (at rates from 0.04 to 0.75 m3 s−1) and collapse. The extrusive activity was accompanied by fluctuating thermal anomalies (0.5–25 MW), by irregular SO2 degassing (700–7000 tons day−1), and by variable explosive activity (4–100 events d−1) producing repeated vulcanian ash plumes (500–5000 m above the crater). Magma budget calculation during the eruptive phase indicates a large excess of degassing, with the volume of degassed magma (0.25–1.28 km3) much higher than the volume of erupted magma (3). Similarly, the thermal energy radiated by the eruption was much higher than that sourced by the dome itself, an unbalance that, by analogy with the degassing, we define as “excess thermal radiation”. Both of these unbalances are consistent with the presence of shallow magma convection that fed the extrusive and explosive activity of the Sabancaya dome.

The blood of the sub-Antarctic fish Eleginops maclovinus (Em) contains three haemoglobins. The major haemoglobin (Hb1Em) displays the Root effect, a drastic decrease in the oxygen affinity and a loss of cooperativity at acidic pH. The carbomonoxy form of HbEm1 has been crystallized in two different crystal forms, orthorhombic (Ortho) and hexagonal (Hexa), and high-resolution diffraction data have been collected for both forms (1.45 and 1.49 Å resolution, respectively). The high-frequency resonance Raman spectra collected from the two crystal forms using excitation at 514 nm were almost indistinguishable. Hb1Em is the first sub-Antarctic fish Hb to be crystallized and its structural characterization will shed light on the molecular mechanisms of cold adaptation and the role of the Root effect in fish haemoglobins.

Since haemoglobins of all animal species have the same haem group, differences in their properties, including oxygen affinity, electrophoretic mobility and pH sensitivity, must result from the interaction of the prosthetic group with specific amino-acid residues in the primary structure. For this reason, fish globins have been the subject of extensive studies in recent years, not only for their structural characteristics, but also because they offer the possibility to investigate the evolutionary history of these ancient molecules in marine and freshwater species living in a great variety of environmental conditions. This review summarizes the current knowledge on the structure, function and phylogeny of haemoglobins of notothenioid fishes. On the basis of crystallographic analysis, the evolution of the Root effect is analysed. Adaptation of the oxygen transport system in notothenioids seems to be based on evolutionary changes, involving levels of biological organization higher than the structure of haemoglobin. These include changes in the rate of haemoglobin synthesis or in regulation by allosteric effectors, which affect the amount of oxygen transported in blood. These factors are thought to be more important for short-term response to environmental challenges than previously believed.

Fishes of the perciform suborder Notothenioidei provide an excellent opportunity for studying the evolution and functional importance of evolutionary adaptations to temperature. To understand the unique biochemical features of high-Antarctic notothenioids, it is important to improve our knowledge of these highly cold-adapted stenotherms with new information on their sub-Antarctic relatives. This paper focuses on the oxygen-transport system of two non-Antarctic species, Eleginops maclovinus and Bovichtus diacanthus. Unlike most Antarctic notothenioids, the blood of E. maclovinus and B. diacanthus displays high hemoglobin (Hb) multiplicity. E. maclovinus, the sister group of Antarctic notothenioids, has one cathodal (Hb C) and two anodal components (Hb 1, Hb 2). B. diacanthus, one of the most northern notothenioids, has three major Hbs. The multiple Hbs may have been maintained as a response to temperature differences and fluctuations of temperate waters, much larger than in the Antarctic. Although non-Antarctic notothenioids have never developed cold adaptation, the amino-acid sequence reveals high identity with the globins of Antarctic notothenioids. Hbs of sub-Antarctic notothenioids are characterised by high oxygen affinity and Root effect. Phylogenetic analyses are consistent with the hypothesis that Bovichtidae and Eleginopidae diverged after they became established in more temperate waters north of the Antarctic Polar Front.

Research has widely supported the efficacy of screening for colorectal cancer in reducing mortality. A blood-based assay potentially represents a more accessible early detection tool for the identification of solid tumor cells originating from a primary tumor site in the body. We demonstrate a relatively easy and highly reproducible technique for the detection of mRNA expression of genes as markers of malignancy in blood samples of patients with colon cancer. The present study aims to identify a set of specific mRNAs expressed in epithelial cells but not in blood cells, which may be useful as markers for early detection of circulating colon cancer cells by a simple, qualitative RT-PCR assay following semi-automated RNA extraction from peripheral blood samples. Our approach includes a systematic search for candidate markers using digital differential display, search on UniGene colon EST libraries and analysis of published data on colon cancer gene expression. A final list included the following genes: bone morphogenetic protein 4 (BMP4), cyclin D (CycD), family with sequence similarity 3, member D (FAM3D), gastrin (GAS), glycoprotein A33 transmembrane (GPA33), glutathione peroxidase 2 gastrointestinal (GPX2), galactoside-binding, soluble, 4 (galectin 4) (LGALS4), non-SMC, structural maintenance of chromosomes, element 1 protein (NSE1), tumor-associated calcium signal transducer 1 (TACSTD1), telomerase reverse transcriptase (hTERT), trefoil factor 3 intestinal (TFF3), transmembrane 4 superfamily member 3 (TM4SF3), UDP glycosyltransferase 1 family, polypeptide A9 (UGT1A9), villin 1 (VIL1), and the novel gene FLJ20127. The mRNA expression of these genes was evaluated in a pool of 16 samples from subjects diagnosed with colon cancer and from 16 normal-controls. We observed expression in 13 of the 15 investigated genes from the blood samples of the vast majority of patients considered, but also in a certain percentage of the controls (from 14.3 to 100%). This finding confirms that the extreme sensitivity of RT-PCR is able to detect minimal amounts of mRNA expressed in a non tissue-specific manner ('illegitimate transcription'). On the contrary, NSE1 and GAS mRNAs were not detected either in patient or in control blood samples; however, they were abundantly expressed in normal and cancerous colon mucosa, encouraging further search for useful markers able to detect epithelial cells in peripheral blood.

Open-vent volcanic activity is typically sustained by ascent and degassing of shallow magma, in which the rate of magma supply to the upper feeding system largely exceeds the rate of magma eruption. Such unbalance between supplied (input) and erupted (output) magma rates is thought to result from steady, degassing-driven, convective magma overturning in a shallow conduit/feeding dyke. Here, we characterize shallow magma circulation at Stromboli volcano by combining independent observations of heat (Volcanic Radiative Power; via satellite images) and gas (SO2, via UV camera) output in a temporal interval (from August 1, 2018 to April 30, 2020) encompassing the summer 2019 effusive eruption and two paroxysmal explosions (on July 3 and August 28, 2019). We show that, during the phase of ordinary strombolian explosive activity that preceded the 2019 effusive eruption, the average magma input rate (0.1-0.2 m3/s) exceeds the magma eruption rate (0.001-0.01 m3/s) by ∼2 orders of magnitude. Conversely, magma input and output rates converge to an average of ∼0.4 m3/s during the summer 2019 summit effusion, implying an overall suppression of magma recycling back into the feeding system, and hence of excess degassing. We find that, during the effusive eruption, the peak in SO2 emissions lags behind the thermal emission peak by ∼27 days, suggesting that magma output, feeding the lava flow field, initially dominates over magma input in the conduit. We propose that this conduit mass unloading, produced by this initial phase of the effusive eruption, leads to an overall decompression (of up to 30 Pa/s) of the shallow plumbing system, ultimately causing ascent of less-dense, volatile-rich magma batch(es) from depth, enhanced explosive activity, and elevated SO2 fluxes culminating into a paroxysmal explosion on August 28. Our results demonstrate that combined analysis of thermal and SO2 flux time-series paves the way to improved understanding of shallow magmatic system dynamics at open-vent volcanoes, and of the transition from explosive to effusive activity regimes.

A vigorously degassing lava lake appeared inside the Santiago pit crater of Masaya volcano (Nicaragua) in December 2015, after years of degassing with no (or minor) incandescence. Here we present an unprecedented-long (3 years) and continuous volcanic gas record that instrumentally characterizes the (re)activation of the lava lake. Our results show that, before appearance of the lake, the volcanic gas plume composition became unusually CO 2 rich, as testified by high CO 2 /SO 2 ratios (mean: 12.2 ± 6.3) and low H 2 O/CO 2 ratios (mean: 2.3 ± 1.3). The volcanic CO 2 flux also peaked in November 2015 (mean: 81.3 ± 40.6 kg/s; maximum: 247 kg/s). Using results of magma degassing models and budgets, we interpret this elevated CO 2 degassing as sourced by degassing of a volatile-rich fast-overturning (3.6–5.2 m 3 s −1 ) magma, supplying CO 2 -rich gas bubbles from minimum equivalent depths of 0.36–1.4 km. We propose this elevated gas bubble supply destabilized the shallow (

Research on selenium has increased in recent years due to its extensive use in electronic applications, solar cells, glass industry, photocopying, cosmetic industry, and as a dietary supplement. New data and discoveries on the importance of this metalloid in the fields of medical biotechnology and human health have further increased its commercial value. This paper identifies challenges associated with selenium recovery from geogenic ores and topical unconventional ores such as marine geo-resources and anthropogenic stocks. Emphasis is given on opportunities and challenges of non-commercial processes for selenium resource extraction that may be developed at full-scale soon. Characteristics and global uses of selenium are also described to help predicting future scenarios of alternate supply. Considering the scarcity of increasingly wanted selenium metal and the recent advancements that have been made in mining from alternative and urban ores, it is possible that selenium can be effectively recovered from other sources to secure a stable and diversified supply.

Mitochondrial functionality is one of the main factors involved in cell survival, and mitochondrial dysfunctions have been identified as an aging hallmark. In particular, the insurgence of mitochondrial dysfunctions is tightly connected to mitochondrial metabolism. During aging, both mitochondrial oxidative and biosynthetic metabolisms are progressively altered, with the development of malfunctions, in turn affecting mitochondrial functionality. In this context, the relation between mitochondrial pathways and aging is evolutionarily conserved from single-celled organisms, such as yeasts, to complex multicellular organisms, such as humans. Useful information has been provided by the yeast Saccharomyces cerevisiae, which is being increasingly acknowledged as a valuable model system to uncover mechanisms underlying cellular longevity in humans. On this basis, we review the impact of specific aspects of mitochondrial metabolism on aging supported by the contributions brought by numerous studies performed employing yeast. Initially, we will focus on the tricarboxylic acid cycle and oxidative phosphorylation, describing how their modulation has consequences on cellular longevity. Afterward, we will report information regarding the importance of nicotinamide adenine dinucleotide (NAD) metabolism during aging, highlighting its relation with mitochondrial functionality. The comprehension of these key points regarding mitochondrial metabolism and their physiological importance is an essential first step for the development of therapeutic interventions that point to increase life quality during aging, therefore promoting “healthy aging,” as well as lifespan itself.

Despite the large number of globins recently discovered in bacteria, our knowledge of their physiological functions is restricted to only a few examples. In the microbial world, globins appear to perform multiple roles in addition to the reversible binding of oxygen; all these functions are attributable to the heme pocket that dominates functional properties. Resistance to nitrosative stress and involvement in oxygen chemistry seem to be the most prevalent functions for bacterial globins, although the number of globins for which functional roles have been studied via mutation and genetic complementation is very limited. The acquisition of structural information has considerably outpaced the physiological and molecular characterisation of these proteins. The genome of the Antarctic cold-adapted bacterium Pseudoalteromonas haloplanktis TAC125 (PhTAC125) contains genes encoding three distinct single-chain 2/2 globins, supporting the hypothesis of their crucial involvement in a number of functions, including protection against oxidative and nitrosative stress in the cold and O2-rich environment. In the genome of PhTAC125, the genes encoding 2/2 globins are constitutively transcribed, thus suggesting that these globins are not functionally redundant in their physiological function in PhTAC125. In the present study, the physiological role of one of the 2/2 globins, Ph-2/2HbO-2217, was investigated by integrating in vivo and in vitro results. This role includes the involvement in the detoxification of reactive nitrogen and O2 species including NO by developing two in vivo and in vitro models to highlight the protective role of Ph-2/2HbO-2217 against reactive nitrogen species. The PSHAa2217 gene was cloned and over-expressed in the flavohemoglobin-deficient mutant of Escherichia coli and the growth properties and O2 uptake in the presence of NO of the mutant carrying the PSHAa2217 gene were analysed. The ferric form of Ph-2/2HbO-2217 is able to catalyse peroxynitrite isomerisation in vitro, indicating its potential role in the scavenging of reactive nitrogen species. Here we present in vitro evidence for the detoxification of NO by Ph-2/2HbO-2217.

Identifying and characterizing strombolian activity from space is a challenging task for satellite-based infrared systems. Stromboli volcano is a natural laboratory that offers a unique opportunity for refining thermal remote-sensing applications that involve transient phenomena and small to moderate hot-spots. A new simple and fast algorithm gave us the opportunity to revisit the MODIS-derived thermal output at Stromboli volcano over the last 13 years. The new algorithm includes both night-time and daytime data and shows high performance with the detection of small-amplitude thermal anomalies ( 1000 MW). The ...

Inflammatory bowel disease (IBD) is an incurable disease which affects millions of people in industrialised countries. Anecdotal and scientific evidence suggest that Cannabis use may have a positive impact in IBD patients. Here, we investigated the effect of cannabigerol (CBG), a non-psychotropic Cannabis-derived cannabinoid, in a murine model of colitis. Colitis was induced in mice by intracolonic administration of dinitrobenzene sulphonic acid (DNBS). Inflammation was assessed by evaluating inflammatory markers/parameters (colon weight/colon length ratio and myeloperoxidase activity), by histological analysis and immunohistochemistry; interleukin-1?, interleukin-10 and interferon-? levels by ELISA, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) by western blot and RT-PCR; CuZn-superoxide dismutase (SOD) activity by a colorimetric assay. Murine macrophages and intestinal epithelial cells were used to evaluate the effect of CBG on nitric oxide production and oxidative stress, respectively. CBG reduced colon weight/colon length ratio, myeloperoxidase activity, and iNOS expression, increased SOD activity and normalized interleukin-1?, interleukin-10 and interferon-? changes associated to DNBS administration. In macrophages, CBG reduced nitric oxide production and iNOS protein (but not mRNA) expression. Rimonabant (a CB1 receptor antagonist) did not change the effect of CBG on nitric oxide production, while SR144528 (a CB2 receptor antagonist) further increased the inhibitory effect of CBG on nitric oxide production. In conclusion, CBG attenuated murine colitis, reduced nitric oxide production in macrophages (effect being modulated by the CB2 receptor) and reduced ROS formation in intestinal epithelial cells. CBG could be considered for clinical experimentation in IBD patients. Graphical abstract

Since 1938, Nyamulagira volcano (Democratic Republic of Congo) has operated as a classic pressurized basaltic closed system, characterized by frequent dike-fed flank eruptions. However, on June 24, 2014, an active lava lake was observed in its summit, after a period of 76 years. The small lava lake is now exposed at the bottom of a pit-crater and is rising and growing. Based on satellite-derived infrared (IR) data, SO2 fluxes and periodic field surveys, we provide evidence that the development of the lava lake was gradual and occurred more than 2 years before it was first observed in the field. Notably, this process followed the voluminous 2011-2012 distal flank eruption and was coeval with weakening of the central rock column below the summit. Hence, the opening and development of the pit-crater favoured the continuous rise of fresh magma through the central conduit and promoted the gradual "re-birth" of the Nyamulagira lava lake. Budgeted volumes of magma erupted, and magma degassed at depth indicate that the formation of the lava lake is due to the draining and refilling of a shallow plumbing system (1-2 km depth), probably in response to the rift-parallel 2011-2012 distal eruption. We thus suggest that the transition from lateral to central activity did not result from a substantial change in the magma supply rate but, more likely, from the perturbation of the plumbing system (and related stress field) associated with the distal eruption. The processes observed at Nyamulagira are not unique and suggest that rift-fissure eruptions, in addition to triggering caldera collapses or lava lake drainages, may also induce a progressive resumption of central vent activity. Current activity at Nyamulagira represents a tangible and major hazard for the population living at the base of its southern flank.

The blood of the sub-Antarctic fish Eleginops maclovinus (Em) contains three haemoglobins. The major haemoglobin (Hb1Em) displays the Root effect, a drastic decrease in the oxygen affinity and a loss of cooperativity at acidic pH. The carbomonoxy form of HbEm1 has been crystallized in two different crystal forms, orthorhombic (Ortho) and hexagonal (Hexa), and high-resolution diffraction data have been collected for both forms (1.45 and 1.49 A ˚ resolution, respectively). The high-frequency resonance Raman spectra collected from the two crystal forms using excitation at 514 nm were almost indistinguishable. Hb1Em is the first sub-Antarctic fish Hb to be crystallized and its structural characterization will shed light on the molecular mechanisms of cold adaptation and the role of the Root effect in fish haemoglobins.

Adenomatous polyposis coli (APC) mutation is the most common genetic change in sporadic colorectal cancer (CRC). Although deregulations of miRNAs have been frequently reported in this malignancy, APC-regulated miRNAs have not been extensively documented. Here, by using an APC-inducible cell line and array analysis, we identified a total of 26 deregulated miRNAs. Among them, members of miR-17-92 cluster were dramatically inhibited by APC and induced by enforced expression of β-catenin. Furthermore, we demonstrate that activated β-catenin resulted from APC loss binds to and activates the miR-17-92 promoter. Notably, enforced expression of miR-19a overrides APC tumor suppressor activity, and knockdown of miR-19a in cancer cells with compromised APC function reduced their aggressive features in vitro. Finally, we observed that expression of miR-19a significantly correlates with β-catenin levels in colorectal cancer specimens, and it is associated to the aggressive stage of tumor progression. Thus, our study reveals that miR-17-92 cluster is directly regulated by APC/β-catenin pathway and could be a potential therapeutic target in colon cancers with aberrant APC/β-catenin signaling.Oncogene advance online publication, 25 January 2016; doi:10.1038/onc.2015.522.

The activation of the insulin-like growth factor 1/IGF1 receptor system (IGF1/IGF1R) is a critical event in the transformation and tumorigenicity processes in a wide variety of human tumors. The IGF1/IGF1R system has been recently studied in carcinoid tumors that often arise in the gastrointestinal tract; these tumors are characterized by hypersecretion of bioamines and neuropeptides, leading to functional tumor disease. Two alternatively spliced IGF1R mRNA transcripts have been described to differ by only three nucleotides (CAG) in the coding sequence, resulting in an amino-acid change from the originally described Thr-Gly to an Arg in the extracellular portion of the receptor beta subunit. In transfected Chinese hamster ovary cells, the form without CAG (CAG-) exhibited an approximate 2-fold increase in IGF1 stimulation of activities required for its mitogenic properties. In this study, we examine the relative expression of the two IGF1R mRNA isoforms by a semiquantitative RT-PCR approach using highly standardized conditions, beta-2 microglobulin (B2M) as a reference gene and gel imaging analysis. We analyzed a large series of human neuroendocrine tumors (32 samples) and 9 normal tissues. A significant higher expression of both isoforms in the tumor samples (approximately 2-fold increase) was found, while a constant CAG+/CAG- IGF1R mRNA isoforms of an approximate 3:1 ratio was observed in all tumoral and normal cell types studied. The phylogenetic study of the IGF1R locus in several species suggests that human IGF1R CAG- mRNA isoform is evolutionarily more recent compared to the IGF1R CAG+ mRNA isoform and it could be used by the splicing apparatus at this intron/exon junction with a lower efficiency. This study highlights the relevance of IGF1R mRNA expression in neuroendocrine tumor cells, and the constant presence of 'subtle' alternative splicing for the IGF1R locus.