102 research outputs found

    The July 2006 eruption of Mount Etna (Italy) monitored through continuous soil radon measurements

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    Radon (222Rn) is a short-lived decay product derived from 238U, with a half-life of only 3.8 days. This gas ascends towards the earth’s surface mainly through cracks or faults. In recent decades radon has been used as a tool for predicting earthquakes and volcanic eruptions, because anomalous variations of its activity have often been reported before the occurrence of such geodynamic events. The recent eruptive activity of Mount Etna in Sicily (Italy) has been documented by multidisciplinary visual, geochemical, and instrumental observations. Here we describe the results obtained during the 10-day July 2006 Strombolian-effusive eruption of Mount Etna by using a radon probe installed near Torre del Filosofo (˜2950 m above sea level). This site is located ˜1 km south of the Southeast Crater, the youngest and most active of the four summit craters of the volcano, and the site of the July 2006 eruption. In order to better interpret the soil radon data we have compared them with simultaneously acquired volcanic tremor signals and a relative measurement of the thermal radiance emitted from the eruption area, derived from thermal camera measurements. During the month prior to the onset of the 2006 eruption, soil radon activity remained at low levels (˜1 x 103 Bq/m3); similar values persisted even when effusive activity started late on 14 July 2006. Only at ˜02:50 on the 15th July, radon activity showed a sharp increase (up to ˜50 x 103 Bq/m3) in a 20 minute interval, and a further increase to ˜20 x 106 Bq/m3 during the following hours. Explosive activity started at 04:30, 100 minutes after the initial rise in soil radon activity. High values in radon activity with numerous peaks persisted through the following four days, and were then followed by a marked decline until early on 20th July, when an extremely sharp rise brought the levels of radon activity to unprecedented values of nearly 1.7 x 108 Bq/m3, and remained very high for the next ˜24 hours. The episode of lava fountaining of 20th July occurred during this interval, starting 10 hours after the maximum in radon activity. From then on through the end of the eruptive phase, the levels of radon activity fluctuated with values rarely exceeding 106 Bq/m3 and then gradually declined starting from around noon on 22nd July. At the end of the eruption, radon levels remained higher (10-100 x 103 Bq/m3) than those recorded before the eruption. In conclusion, the onset of the Strombolian activity (15 July) and the lava fountaining (20 July) were related to significant changes in the magma pressure within the conduit. These two events were preceded by some hours with increases in radon soil emission by 4-5 orders of magnitude. For this reason we can imagine in the future the use of this signal as a potential precursor of this type of volcanic activity. Minor changes in eruptive behaviour did not produce significant variations in the monitored parameters. We interpret peaks in radon activity as due primarily to microfracturing of uranium-bearing rock. These observations suggest that radon measurements in the summit area of Etna are strongly controlled by the state of stress within the volcano and demonstrate the usefulness of radon data acquisition before and during eruptions

    The BINGO project: II. Instrument description

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    Context. The measurement of diffuse 21-cm radiation from the hyperfine transition of neutral hydrogen (Hi signal) in different redshifts is an important tool for modern cosmology. However, detecting this faint signal with non-cryogenic receivers in single-dish telescopes is a challenging task. The BINGO (Baryon Acoustic Oscillations from Integrated Neutral Gas Observations) radio telescope is an instrument designed to detect baryonic acoustic oscillations (BAOs) in the cosmological Hi signal, in the redshift interval 0:127 ≤ z ≤ 0:449. Aims. This paper describes the BINGO radio telescope, including the current status of the optics, receiver, observational strategy, calibration, and the site. Methods. BINGO has been carefully designed to minimize systematics, being a transit instrument with no moving dishes and 28 horns operating in the frequency range 980 ≤ v ≤ 1260 MHz. Comprehensive laboratory tests were conducted for many of the BINGO subsystems and the prototypes of the receiver chain, horn, polarizer, magic tees, and transitions have been successfully tested between 2018-2020. The survey was designed to cover ∼13% of the sky, with the primary mirror pointing at declination δ = -15°. The telescope will see an instantaneous declination strip of 14:75. Results. The results of the prototype tests closely meet those obtained during the modeling process, suggesting BINGO will perform according to our expectations. After one year of observations with a 60% duty cycle and 28 horns, BINGO should achieve an expected sensitivity of 102μK per 9.33MHz frequency channel, one polarization, and be able to measure the Hi power spectrum in a competitive time frame

    Volcanoes: effusions and explosions. Interactive exhibits to understand how volcanoes work

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    The Educational & Outreach Group (EOG) of the Istituto Nazionale di Geofisica & Vulcanologia created a portable museum to provide educational opportunities in volcanology, volcanic risk and Earth science for students and visitors. The EOG developed this project for the "Festival della Scienza", organized in Genoa, Italy, in October - November, 2007, which was a parade of over 200 events, including scientific and technological exhibitions, workshops, meetings, lectures, books and video presentations. In this museum visitors can successively see many posters and movies and play with interactive exhibits. A little 3D-movie shows the Big Bang, the formation of Solar System and, in particular the formation of the Earth. Many interactive exhibits illustrate why, where and when earthquakes and volcanic eruptions occur around the world and allow to introduce the visitor to the plate tectonics theory. A 3D magnetic plate tectonic puzzle can be put down and reconstructed by visitors to understand the Earth’s surface configuration. Then two other 3D Earth models show what drives the plates and the inner Earth structure. An interactive program illustrates where and when earthquakes and volcanic eruptions occur in accelerated time on maps of various areas around the world. Playing with a block diagram it is possible to produce an earthquake along a 1 meter long strike slip fault in a destroying all the man-made constructions close to it. A little movie introduces to volcanoes’ world. Two small interactive exhibits allow visitors to understand the mechanism for the explosive and the effusive eruptions. Two other exciting interactive exhibits allow visitors to “create” two different eruptions: the explosive and the effusive ones. It is possible to get inside a volcano (a 2 meter high interactive exhibit) to attend an eruption from the magmatic chamber to the Earth surface. A big hall is completed dedicated to Italian volcanoes (Vesuvio, Campi Flegrei, Etna, Stromboli, Vulcano, Colli Albani); some of them are reproduced with 3D models or described by short movies. The museum finishes with the visit of the volcanic survey hall of Stromboli, seeing - in real time - seismic data, three different webcams, geochemical and strain data. The INGV Museum had remarkably successful, reaching more than 7,500 children and adults yet in 13 days, also thanks to 30 volcanologists as very special guides. The Educational & Outreach Group: M. Pignone, A. Tertulliani, M. De Lucia, M. Di Vito, P. Landi, P. Madonia, M. Martini, R. Nave, M. Neri, P. Scarlato, J. Taddeucci, R. Moschillo, S. Tarquini, G. Vilardo, A. Bonforte, L. Calderone, F. Cannavò, W. De Cesare, P. Ficeli, S. Inguaggiato, M. Mattia, G. Puglisi, S. Morici, D. Reitano, D. Richichi, G. Scarpato, B. Angioni, F. Di Laura, S. Palone, D. Riposat

    The quality of life of patients with genital warts: a qualitative study

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    <p>Abstract</p> <p>Background</p> <p>Genital warts, which are caused by infection with human papillomavirus (HPV), are one of the most common sexually transmitted diseases in Europe. Although genital warts are commonly perceived as a non-serious condition, treatment is often long, of varying effectiveness and the recurrence rate is high. Very few studies have been performed on the personal consequences of genital warts. The aim of this qualitative study, set in Denmark, was to examine the ways in which genital warts may affect patients' quality of life.</p> <p>Methods</p> <p>To obtain an in-depth understanding of patients' perceptions of genital warts, we used qualitative focus-group interviews with five men and five women aged between 18 and 30 years who had genital warts. The interview guide was based on a literature review that identified important issues and questions. The data were analysed using a medical anthropological approach.</p> <p>Results</p> <p>Patients' experiences were related to cultural conceptions of venereal diseases and the respective identities and sexuality of the sexes. The disease had negative psychological and social effects both for men and for women and it affected their sex and love lives, in particular. The psychological burden of the disease was increased by the uncertain timeline and the varying effectiveness of treatment. We identified a need for more patient information about the disease and its psycho-sexual aspects.</p> <p>Conclusions</p> <p>The men and women participating in this study considered their quality of life to be significantly lowered because of genital warts. The experiences described by the participants give insights that may be valuable in treatment and counselling.</p> <p>The quadrivalent HPV vaccine that has now been added to the childhood vaccination programme for girls in Denmark for the prevention of cervical cancer can also prevent 90% of cases of genital warts. Our results suggest that HPV vaccination could considerably reduce the largely unacknowledged psychological and social burden associated with genital warts, in men as well as women.</p

    Molecular Mechanisms Generating and Stabilizing Terminal 22q13 Deletions in 44 Subjects with Phelan/McDermid Syndrome

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    In this study, we used deletions at 22q13, which represent a substantial source of human pathology (Phelan/McDermid syndrome), as a model for investigating the molecular mechanisms of terminal deletions that are currently poorly understood. We characterized at the molecular level the genomic rearrangement in 44 unrelated patients with 22q13 monosomy resulting from simple terminal deletions (72%), ring chromosomes (14%), and unbalanced translocations (7%). We also discovered interstitial deletions between 17–74 kb in 9% of the patients. Haploinsufficiency of the SHANK3 gene, confirmed in all rearrangements, is very likely the cause of the major neurological features associated with PMS. SHANK3 mutations can also result in language and/or social interaction disabilities. We determined the breakpoint junctions in 29 cases, providing a realistic snapshot of the variety of mechanisms driving non-recurrent deletion and repair at chromosome ends. De novo telomere synthesis and telomere capture are used to repair terminal deletions; non-homologous end-joining or microhomology-mediated break-induced replication is probably involved in ring 22 formation and translocations; non-homologous end-joining and fork stalling and template switching prevail in cases with interstitial 22q13.3. For the first time, we also demonstrated that distinct stabilizing events of the same terminal deletion can occur in different early embryonic cells, proving that terminal deletions can be repaired by multistep healing events and supporting the recent hypothesis that rare pathogenic germline rearrangements may have mitotic origin. Finally, the progressive clinical deterioration observed throughout the longitudinal medical history of three subjects over forty years supports the hypothesis of a role for SHANK3 haploinsufficiency in neurological deterioration, in addition to its involvement in the neurobehavioral phenotype of PMS

    Association of kidney disease measures with risk of renal function worsening in patients with type 1 diabetes

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    Background: Albuminuria has been classically considered a marker of kidney damage progression in diabetic patients and it is routinely assessed to monitor kidney function. However, the role of a mild GFR reduction on the development of stage 653 CKD has been less explored in type 1 diabetes mellitus (T1DM) patients. Aim of the present study was to evaluate the prognostic role of kidney disease measures, namely albuminuria and reduced GFR, on the development of stage 653 CKD in a large cohort of patients affected by T1DM. Methods: A total of 4284 patients affected by T1DM followed-up at 76 diabetes centers participating to the Italian Association of Clinical Diabetologists (Associazione Medici Diabetologi, AMD) initiative constitutes the study population. Urinary albumin excretion (ACR) and estimated GFR (eGFR) were retrieved and analyzed. The incidence of stage 653 CKD (eGFR &lt; 60 mL/min/1.73 m2) or eGFR reduction &gt; 30% from baseline was evaluated. Results: The mean estimated GFR was 98 \ub1 17 mL/min/1.73m2 and the proportion of patients with albuminuria was 15.3% (n = 654) at baseline. About 8% (n = 337) of patients developed one of the two renal endpoints during the 4-year follow-up period. Age, albuminuria (micro or macro) and baseline eGFR &lt; 90 ml/min/m2 were independent risk factors for stage 653 CKD and renal function worsening. When compared to patients with eGFR &gt; 90 ml/min/1.73m2 and normoalbuminuria, those with albuminuria at baseline had a 1.69 greater risk of reaching stage 3 CKD, while patients with mild eGFR reduction (i.e. eGFR between 90 and 60 mL/min/1.73 m2) show a 3.81 greater risk that rose to 8.24 for those patients with albuminuria and mild eGFR reduction at baseline. Conclusions: Albuminuria and eGFR reduction represent independent risk factors for incident stage 653 CKD in T1DM patients. The simultaneous occurrence of reduced eGFR and albuminuria have a synergistic effect on renal function worsening
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