| 41. |
- Aiuppa, Sandro, et al.
(author)
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Tracking formation of a lava lake from ground and space: Masaya volcano (Nicaragua), 2015-2017
- 2018
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In: Geochemistry, Geophysics, Geosystems. - 1525-2027. ; 19:2, s. 496-515
-
Journal article (peer-reviewed)abstract
- 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 CO2-rich, as testified by high CO2/SO2 ratios (mean, 12.2±6.3) and low H2O/CO2 ratios (mean, 2.3±1.3). The volcanic CO2 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 CO2 degassing as sourced by degassing of a volatile-rich fast-convecting (3.6-5.2 m3·s-1) magma, supplying CO2-rich gas bubbles from minimum equivalent depths of 0.36-1.4 km. We propose this elevated gas bubbles supply destabilized the shallow (<1 km) Masaya magma reservoir, leading to upward migration of vesicular (buoyant) resident magma, and ultimately to (re)formation of the lava lake. At onset of lava lake activity on 11 December 2015 (constrained by satellite-based (MODIS) thermal observations), the gas emissions transitioned to more SO2-rich composition, and the SO2 flux increased by a factor ~40 % (11.4±5.2 kg/s) relative to background degassing (8.0 kg/s), confirming faster than normal (4.4 vs. ~3 m3·s-1) shallow magma convection. Elevated shallow magma circulation is also supported by gradual increase in irradiated thermal energy, captured by MODIS, from which we calculate that 0.4-0.8 m3·s-1 of magma have been surface-emplaced since December 2015.
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| 42. |
- Arpaia, Riccardo, 1985, et al.
(author)
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Dynamical charge density fluctuations pervading the phase diagram of a Cu-based high-Tc superconductor
- 2019
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In: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 365:6456, s. 906-910
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Journal article (peer-reviewed)abstract
- Charge density modulations have been observed in all families of high–critical temperature (Tc) superconducting cuprates. Although they are consistently found in the underdoped region of the phase diagram and at relatively low temperatures, it is still unclear to what extent they influence the unusual properties of these systems. Using resonant x-ray scattering, we carefully determined the temperature dependence of charge density modulations in YBa2Cu3O7–d and Nd1+xBa2–xCu3O7–d for several doping levels. We isolated short-range dynamical charge density fluctuations in addition to the previously known quasi-critical charge density waves. They persist up to well above the pseudogap temperature T*, are characterized by energies of a few milli–electron volts, and pervade a large area of the phase diagram.
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| 43. |
- Arun, K. G., et al.
(author)
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New horizons for fundamental physics with LISA
- 2022
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In: Living Reviews in Relativity. - : Springer Science and Business Media LLC. - 1433-8351 .- 2367-3613. ; 25:1
-
Research review (peer-reviewed)abstract
- The Laser Interferometer Space Antenna (LISA) has the potential to reveal wonders about the fundamental theory of nature at play in the extreme gravity regime, where the gravitational interaction is both strong and dynamical. In this white paper, the Fundamental Physics Working Group of the LISA Consortium summarizes the current topics in fundamental physics where LISA observations of gravitational waves can be expected to provide key input. We provide the briefest of reviews to then delineate avenues for future research directions and to discuss connections between this working group, other working groups and the consortium work package teams. These connections must be developed for LISA to live up to its science potential in these areas.
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| 44. |
- Braicovich, Lucio, et al.
(author)
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Determining the electron-phonon coupling in superconducting cuprates by resonant inelastic x-ray scattering: Methods and results on Nd1+xBa2-xCu3O7-δ
- 2020
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In: Physical Review Research. - 2643-1564. ; 2:2
-
Journal article (peer-reviewed)abstract
- The coupling between lattice vibration quanta and valence electrons can induce charge-density modulations and decisively influence the transport properties of materials, e.g., leading to conventional superconductivity. In high-critical-temperature superconductors, where electronic correlation is the main actor, the actual role of electron-phonon coupling (EPC) is being intensely debated theoretically and investigated experimentally. We present an in-depth study of how the EPC strength can be obtained directly from resonant inelastic x-ray scattering (RIXS) data through the theoretical approach derived by Ament et al. [Europhys. Lett. 95, 27008 (2011)]. The role of the model parameters (e.g., phonon energy ω0, intermediate state lifetime 1/Γ, EPC matrix element M, and detuning energy Ω) is thoroughly analyzed, providing general relations among them that can be used to make quantitative estimates of the dimensionless EPC g=(M/ω0)2 without detailed microscopic modeling. We then apply these methods to very high-resolution Cu L3-edge RIXS spectra of three Nd1+xBa2−xCu3O7−δ films. For the insulating antiferromagnetic parent compound, the value of M as a function of the in-plane momentum transfer is obtained for Cu-O bond-stretching (breathing) and bond-bending (buckling) phonon branches. For the underdoped and the nearly optimally doped samples, the effects of Coulomb screening and of charge-density-wave correlations on M are assessed. In light of the anticipated further improvements of the RIXS experimental resolution, this work provides a solid framework for an exhaustive investigation of the EPC in cuprates and other quantum materials.
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| 45. |
- Casanueva, Felipe F., et al.
(author)
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Criteria for the definition of Pituitary Tumor Centers of Excellence (PTCOE): A Pituitary Society Statement
- 2017
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In: Pituitary. - : Springer Science and Business Media LLC. - 1386-341X .- 1573-7403. ; 20, s. 489-498
-
Research review (peer-reviewed)abstract
- © 2017, The Author(s). Introduction: With the goal of generate uniform criteria among centers dealing with pituitary tumors and to enhance patient care, the Pituitary Society decided to generate criteria for developing Pituitary Tumors Centers of Excellence (PTCOE). Methods: To develop that task, a group of ten experts served as a Task Force and through two years of iterative work an initial draft was elaborated. This draft was discussed, modified and finally approved by the Board of Directors of the Pituitary Society. Such document was presented and debated at a specific session of the Congress of the Pituitary Society, Orlando 2017, and suggestions were incorporated. Finally the document was distributed to a large group of global experts that introduced further modifications with final endorsement. Results: After five years of iterative work a document with the ideal criteria for a PTCOE is presented. Conclusions: Acknowledging that very few centers in the world, if any, likely fulfill the requirements here presented, the document may be a tool to guide improvements of care delivery to patients with pituitary disorders. All these criteria must be accommodated to the regulations and organization of Health of a given country.
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| 46. |
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| 47. |
- D'Amicis, Raffaella, et al.
(author)
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Investigating Alfvenic Turbulence in Fast and Slow Solar Wind Streams
- 2022
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In: Universe. - : MDPI. - 2218-1997. ; 8:7
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Journal article (peer-reviewed)abstract
- Solar wind turbulence dominated by large-amplitude Alfvenic fluctuations, mainly propagating away from the Sun, is ubiquitous in high-speed solar wind streams. Recent observations performed in the inner heliosphere (from 1 AU down to tens of solar radii) have proved that also slow wind streams show sometimes strong Alfvenic signatures. Within this context, the present paper focuses on a comparative study on the characterization of Alfvenic turbulence in fast and slow solar wind intervals observed at 1 AU where degradation of Alfvenic correlations is expected. In particular, we compared the behavior of different parameters to characterize the Alfvenic content of the fluctuations, using also the Elsasser variables to derive the spectral behavior of the normalized cross-helicity and residual energy. This study confirms that the Alfvenic slow wind stream resembles, in many respects, a fast wind stream. The velocity-magnetic field (v-b) correlation coefficient is similar in the two cases as well as the amplitude of the fluctuations although it is not clear to what extent the condition of incompressibility holds. Moreover, the spectral analysis shows that fast wind and Alfvenic slow wind have similar normalized cross-helicity values but in general the fast wind streams are closer to energy equipartition. Despite the overall similarities between the two solar wind regimes, each stream shows also peculiar features, that could be linked to the intrinsic evolution history that each of them has experienced and that should be taken into account to investigate how and why Alfvenicity evolves in the inner heliosphere.
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| 48. |
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| 49. |
- Dorigo, Wouter, et al.
(author)
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The International Soil Moisture Network : Serving Earth system science for over a decade
- 2021
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In: Hydrology and Earth System Sciences. - : Copernicus GmbH. - 1027-5606 .- 1607-7938. ; 25:11, s. 5749-5804
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Research review (peer-reviewed)abstract
- In 2009, the International Soil Moisture Network (ISMN) was initiated as a community effort, funded by the European Space Agency, to serve as a centralised data hosting facility for globally available in situ soil moisture measurements . The ISMN brings together in situ soil moisture measurements collected and freely shared by a multitude of organisations, harmonises them in terms of units and sampling rates, applies advanced quality control, and stores them in a database. Users can freely retrieve the data from this database through an online web portal (https://ismn.earth/en/, last access: 28 October 2021). Meanwhile, the ISMN has evolved into the primary in situ soil moisture reference database worldwide, as evidenced by more than 3000 active users and over 1000 scientific publications referencing the data sets provided by the network. As of July 2021, the ISMN now contains the data of 71 networks and 2842 stations located all over the globe, with a time period spanning from 1952 to the present. The number of networks and stations covered by the ISMN is still growing, and approximately 70 % of the data sets contained in the database continue to be updated on a regular or irregular basis. The main scope of this paper is to inform readers about the evolution of the ISMN over the past decade, including a description of network and data set updates and quality control procedures. A comprehensive review of the existing literature making use of ISMN data is also provided in order to identify current limitations in functionality and data usage and to shape priorities for the next decade of operations of this unique community-based data repository.
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| 50. |
- Dratva, Julia, et al.
(author)
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Early Life Origins of Lung Ageing : Early Life Exposures and Lung Function Decline in Adulthood in Two European Cohorts Aged 28-73 Years
- 2016
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In: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 11:1
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Journal article (peer-reviewed)abstract
- Objectives Early life environment is essential for lung growth and maximally attained lung function. Whether early life exposures impact on lung function decline in adulthood, an indicator of lung ageing, has scarcely been studied. Methods Spirometry data from two time points (follow-up time 9-11 years) and information on early life exposures, health and life-style were available from 12862 persons aged 28-73 years participating in the European population-based cohorts SAPALDIA (n = 5705) and ECRHS (n = 7157). The associations of early life exposures with lung function (FEV1) decline were analysed using mixed-effects linear regression. Results Early life exposures were significantly associated with FEV1 decline, with estimates almost as large as personal smoking. FEV1 declined more rapidly among subjects born during the winter season (adjusted difference in FEV1/year of follow-up [95% CI] -2.04ml [-3.29;-0.80]), of older mothers, (-1.82 ml [-3.14;-0.49]) of smoking mothers (-1.82ml [-3.30;-0.34] or with younger siblings (-2.61ml [-3.85;-1.38]). Less rapid FEV1-decline was found in subjects who had attended daycare (3.98ml [2.78; 5.18]), and indicated in subjects with pets in childhood (0.97ml [-0.16; 2.09]). High maternal age and maternal smoking appeared to potentiate effects of personal smoking. The effects were independent of asthma at any age. Conclusion Early life factors predicted lung function decline decades later, suggesting that some mechanisms related lung ageing may be established early in life. Early life programming of susceptibility to adult insults could be a possible pathway that should be explored further.
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