37 research outputs found

    Climatic control on seasonal variations in mountain glacier surface velocity

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    Accurate measurements of ice flow are essential to predict future changes in glaciers and ice caps. Glacier displacement can in principle be measured on the large scale by cross-correlation of satellite images. At weekly to monthly scales, the expected displacement is often of the same order as the noise for the commonly used satellite images, complicating the retrieval of accurate glacier velocity. Assessments of velocity changes on short timescales and over complex areas such as mountain ranges are therefore still lacking but are essential to better understand how glacier dynamics are driven by internal and external factors. In this study, we take advantage of the wide availability and redundancy of satellite imagery over the western Pamirs to retrieve glacier velocity changes over 10 d intervals for 7 years and for a wide range of glacier geometry and dynamics. Our results reveal strong seasonal trends. In spring/summer, we observe velocity increases of up to 300 % compared to a slow winter period. These accelerations clearly migrate upglacier throughout the melt season, which we link to changes in subglacial hydrology efficiency. In autumn, we observe glacier accelerations that have rarely been observed before. These episodes are primarily confined to the upper ablation zone with a clear downglacier migration. We suggest that they result from glacier instabilities caused by sudden subglacial pressurization in response to (1) supraglacial pond drainage and/or (2) gradual closure of the hydrological system. Our 10 d resolved measurements allow us to characterize the short-term response of glaciers to changing meteorological and climatic conditions

    Insidious diagnosis of breast cancer in patient with previous macrolaneTM breast infiltration: A case-report

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    Breast augmentation is one of the most performed aesthetic surgery. In addition to the silicone breast implants, hyaluronic acid base fillers represent a non-surgical alternative. There are different types of hyaluronic acid for this purpose, including MacrolaneTM. In addition to the classic complications associated with the mammary injection of these fillers, Macrolane may cause a well-known radiological ambiguity potentially leading to a delay in the diagnosis of an underlying breast cancer. The patient underwent breast augmentation with hyaluronic acid and after several years from the procedure she noted the appearance of subcutaneous nodules and discontinuous mastodynia, attributed to previous Macrolane infiltrations: unfortunately the radiological images did not immediately show the underlying contextual cancer of the right breast. Patient underwent therapeutic right mastectomy and prophylactic left mastectomy, because of the presence of BRCA1 mutation. Simultaneously we performed an immediate reconstruction with mammary implants and biological meshes. No complications arose in the follow up. Several authors have already carried out studies on Macrolane focusing on its interference and delay in the diagnosis of malignant breast diseases. At present there is only one other case in literature reporting on a patient diagnosed with physical and instrumental examinations and delaying the diagnosis. We believe that the use of hyaluronic acid (Macrolane) fillers for breast augmentation should be avoided. In view of the complexity of these cases, a multidisciplinary approach is always advisable: we believe that a continuous dialogue between the Plastic surgeon, the Breast-dedicated Radiologist and the Oncologist is pivotal

    Survey Hardware IT Scientifico INAF

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    Si è più volte ricordato che tra la strumentazione avanzata per l’osservazione dell’Universo un ruolo essenziale, e non secondario, va allo strumento IT nel suo insieme. Questo strumento si compone di diverse componenti, dal hardware al software fino al networking tra il “capitale umano”. Armonizzare, sviluppare ed integrare adeguatamente le varie componenti ha permesso e permette ai progetti di ottenere un livello di eccellenza nazionale ed internazionale, ma la loro armonizzazione sta diventando complicata soprattutto in vista dei grandi progetti e della sostenibilità dell’infrastruttura. L’ICT dell’INAF fino al 2021 ha cercato di valorizzare l’esperienza acquisita nei vari campi IT facendo da stimolo nella creazione di gruppi di lavoro sulle varie tematiche, organizzando corsi su strumenti specifici, linguaggi di programmazione, e sviluppando un prototipo organizzativo per una infrastruttura più ampia che non fosse dedicata al singolo progetto, ma che permettesse l’ottimizzazione, soprattutto del capitale umano, necessario per i singoli progetti e per le attività di “long tail of science”. Data la richiesta di riorganizzazione l’IT in INAF, si e’ voluto fare uno snapshoot della situazione attuale, e di quella di sicura acquisizione, in modo da poter meglio organizzare i prossimi passi infrastrutturali. Si ‘e quindi richiesta la collaborazione dei direttori delle Strutture, dei responsabili dei progetti e della comunità tutta affinché compili in modo adeguato le schede della loro infrastruttura scientifica IT sopra un certo livello di core e Storage (indicativamente sopra i 100 core e i 100 TB di storage). Il disegno che ne risulta è una mappa frammentata di HW, in parte derivante anche da infrastruttura non direttamente dell’INAF. Non è lo scopo di questo documento quello di voler estrapolare conclusioni, ma serve per tenere traccia dell’infrastruttura IT, e quindi si pensa di aggiornarlo regolarmente

    CDK4/6-Inhibitors Versus Chemotherapy in Advanced HR+/HER2-Negative Breast Cancer: Results and Correlative Biomarker Analyses of the KENDO Randomized Phase II Trial

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    Background: The optimal treatment approach for hormone receptor-positive/HER2-negative metastatic breast cancer (HR+/HER2-negative MBC) with aggressive characteristics remains controversial, with lack of randomized trials comparing cyclin-dependent kinase (CDK)4/6-inhibitors (CDK4/6i) + endocrine therapy (ET) with chemotherapy + ET. Materials and methods: We conducted an open-label randomized phase II trial (NCT03227328) to investigate whether chemotherapy + ET is superior to CDK4/6i + ET for HR+/HER2-negative MBC with aggressive features. PAM50 intrinsic subtypes (IS), immunological features, and gene expression were assessed on baseline samples. Results: Among 49 randomized patients (median follow-up: 35.2 months), median progression-free survival (mPFS) with chemotherapy + ET (11.2 months, 95% confidence interval [CI]: 7.7-15.4) was numerically shorter than mPFS (19.9 months, 95% CI: 9.0-30.6) with CDK4/6i + ET (hazard ratio: 1.41, 95% CI: 0.75-2.64). Basal-like tumors under CDK4/6i + ET exhibited worse PFS (mPFS: 11.4 months, 95% CI: 3.00-not reached [NR]) and overall survival (OS; mOS: 18.8 months, 95% CI: 18.8-NR) compared to other subtypes (mPFS: 20.7 months, 95% CI: 9.00-33.4; mOS: NR, 95% CI: 24.4-NR). In the chemotherapy arm, luminal A tumors showed poorer PFS (mPFS: 5.1 months, 95% CI: 2.7-NR) than other IS (mPFS: 13.2 months, 95% CI: 10.6-28.1). Genes/pathways involved in BC cell survival and proliferation were associated with worse outcomes, as opposite to most immune-related genes/signatures, especially in the CDK4/6i arm. CD24 was the only gene significantly associated with worse PFS in both arms. Tertiary lymphoid structures and higher tumor-infiltrating lymphocytes also showed favorable survival trends in the CDK4/6i arm. Conclusions: The KENDO trial, although closed prematurely, adds further evidence supporting CDK4/6i + ET use in aggressive HR+/HER2-negative MBC instead of chemotherapy. PAM50 IS, genomic, and immunological features are promising biomarkers to personalize therapeutic choices

    Seismic investigation of an Arctic glacier accelerating under climate warming

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    <p>The data shared here at the one used in the associated paper. They focus on the Arctic glacier Kongsvegen (check location here: https://toposvalbard.npolar.no/), in Svalbard and are linked to the mammamia project (https://www.mn.uio.no/geo/english/research/projects/mammamia/). They are composed of DEM, modelled runoff and seismic measurements. All the processing is detailed in the associated paper. Please cite both the paper and the dataset when using this data. Feel free to reach out if needed.</p><ul><li><i>DEM_dataset_Nanni</i>: glacier surface elevation from 2013 to 2022, glacier bed elevation, dh/dt from 2000 to 2020 (from https://www.theia-land.fr/product/altitude-des-glaciers/). Format: georeferenced .tif.</li><li><i>runoff_1992to2022</i>: runoff at a 3 hour time step at grid point specified by <strong>lat</strong>, <strong>lon</strong> and time specified by <strong>time</strong>. Data is processed following https://doi.org/10.5194/tc-17-2941-2023. Format: .txt tab separated</li><li><i>PSD_NANNI</i>: contains all power spectral density of all seismic stations from 2018 to 2023 for the vertical component. For each year and each station there are 3 files: <strong>frequency</strong> (frequency at which was computed the PSD), <strong>time</strong> (time at which was computed the PSD) and the <strong>PSD</strong> file that contains the PSD value at each (time,frequency) pair. Do not pay attention at the terms corr or resampled in the files names. Note that not all stations have continuous record. KNG stations are for the period 2018-2019, KGS for 2020-2023. Format: .txt tab separated.</li><li><i>PSD_KGS_figure</i>: plotted PSD for each year-station pair for the vertical component.</li><li><i>METADATA_NANNI</i>: contains the stations location and the group to which their belong.</li><li><i>ICEQUAKE_NANNI</i>: contains the time (<strong>time</strong>), amplitude (<strong>mean</strong> and <strong>median</strong>) and rate (<strong>rate </strong>in event per hour) of the icequake detection for each station (<strong>stations</strong>). Format: .txt tab separated. This was computed with STA/LTA, see paper for details.</li></ul><p> </p&gt

    Etude sismologique de la dynamique du réseau hydrologique sous-glaciaire d'un glacier alpin

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    The way in which water flows in the subglacial environment exerts a major control on ice-bed mechanical coupling, which strongly defines glacier sliding speeds. Today our understanding on the physics of the subglacial hydrology network is limited because of the scarcity of field measurements that yield a partial representation of the heterogeneous subglacial environment. The aim of my PhD work is to use passive seismology to help overcome common observational difficulties and quantify the evolution of the subglacial hydrology network pressure conditions and its configuration. Recent works show that subglacial turbulent water flow generates seismic noise that can be related to the associated hydrodynamics properties. These analyses were conducted over a limited period of time making it unclear whether such approach is appropriate to investigate seasonal and diurnal timescales, I.e. when subglacial water flow influences the most glacier dynamics. In addition, previous studies did not consider spatial changes in the heterogeneous drainage system, and until now, almost no study has located seismic noise sources spatially scattered and temporally varying. In this PhD work I address those seismological-challenges in order to resolve the subglacial hydrology dynamics in time and space.We acquired a 2-year long continuous dataset of subglacial-water-flow-induced seismic power as well as in-situ measured glacier basal sliding speed and subglacial water discharge from the Glacier d'Argentière (French Alps). I show that a careful investigation of the seismic power within [3-7] Hz can characterize the subglacial water flow hydrodynamics from seasonal to hourly timescales and across a wide range of water discharge (from 0.25 to 10 m3/sec). Combining such observations with adequate physical frameworks, I then inverted the associated hydraulic pressure gradient and hydraulic radii. I observed that the seasonal dynamics of subglacial channels is characterized by two distinct regimes. At low discharge, channels behave at equilibrium and accommodate variations in discharge mainly through changes in hydraulic radius. At a high discharge rate and with pronounced diurnal water-supply variability, channels behave out of equilibrium and undergo strong changes in the hydraulic pressure gradient, which may help sustain high water pressure in cavities and favor high glacier sliding speed over the summer.We then conducted a one-month long dense seismic-array experiment supplemented by glacier ice-thickness and surface velocity measurements. Using this unique dataset, I developed a novel methodology to overcome the challenge of locating seismic noise sources spatially scattered and temporally varying. Doing so, I successfully retrieve the first two-dimensional map of the subglacial drainage system as well as its day-to-day evolution. Using this map, I characterize when and where the subglacial drainage system is distributed through connected cavities, which favour rapid glacier flow versus localized through a channelized system that prevents rapid glacier flow. In addition, I also use high frequency seismic ground motion amplitude to study glacier features such as crevasses, thickness or ice anisotropy in a complementary way to what is traditionally done with seismic phase analysis.The first outcome of this cross-boundary PhD work is that one can analyse passive seismic measurements to retrieve the temporal evolution of subglacial channels pressure and geometry conditions over a complete melt-season. The second is that dense seismic array measurements can be used to resolve the subglacial drainage system spatial configuration and observe the switch from distributed to localized subglacial water flow. Such advances open the way for studying similar subglacial process on different sites and in particular in Greenland and Antarctica. This also concerns numerous sub-surface environment that host similar process such as volcanoes, karst, and landslides.La façon dont l'eau s'écoule sous les glaciers joue un rôle majeur dans le couplage mécanique glace-roche qui définit les vitesses d’écoulement des glaciers. Aujourd'hui, notre compréhension de la physique de l'hydrologie sous-glaciaire est limitée et incertaine en raison de la rareté des mesures de terrain, qui ne représentent que partiellement l’hétérogénéité de l’environnement sous-glaciaire. L'objectif de mon doctorat est d'utiliser la sismologie passive pour surmonter les difficultés observationnelles et quantifier l’évolution des conditions de pression et de la configuration du réseau d’hydrologie sous glaciaire. De récents travaux montrent que l'écoulement turbulent d'eaux sous-glaciaire génère du bruit sismique dont l’étude donne accès aux propriétés hydrodynamique associées. Ces analyses ont été menées sur une courte période et il n’est pas certains qu’elles soient appropriées à l’étude de l’hydrologie sous-glaciaire sur les échelles de temps les plus représentative de son influence sur la dynamique glaciaire (saisonnières et diurnes). De plus, ces études ne considèrent pas de changements dans la configuration des réseaux hydrologique et il existe peu d’étude ayant localisé des sources de bruit sismique spatialement éparses et temporellement variables. Dans ce doctorat, j'aborde ces défis sismologiques afin de résoudre la dynamique de l'hydrologie sous-glaciaire.Nous avons acquis sur le glacier d'Argentière (Alpes) un jeu de données continu sur 2 ans permettant d’évaluer la puissance sismique induite par les flux d'eau sous-glaciaire et de la comparer à des mesures de la vitesse de glissement basale et du débit d'eau sous-glaciaire. Je montre que l'étude de la puissance sismique à [3-7] Hz donne accès aux propriétés l'hydrodynamique des flux d'eau sous-glaciaires sur des échelles de temps tant saisonnière qu’horaire et sur une gamme de débits de 0.25 à 10 m3/sec. Avec un cadre physique adéquat j'inverse, de ces observations, les gradients de pression et rayons hydrauliques associés et identifie une dynamique saisonnière des chenaux sous-glaciaire. À faible débit, les chenaux se comportent à l'équilibre et s'adaptent aux variations de débit par des changements de rayon hydraulique. À fort débit et forte variabilité diurne en apport d'eau, les chenaux se comportent hors équilibre et subissent de fortes variations du gradient de pression hydraulique qui maintiennent de fortes pression d'eau dans les cavités et favorisent des vitesses de glissement élevées.Nous avons mené une expérience d'un mois avec un réseau sismique dense, complétée par des mesures d'épaisseur et de vitesse de surface du glacier. Sur cette base j'ai développé une méthodologie pour relever le défi de localiser des sources de bruit sismique spatialement éparses et temporellement variables. Ce faisant, j'ai obtenu une carte du système de drainage sous-glaciaire ainsi que son évolution journalière. J’ai pu ainsi observer quand et où ce système est distribué à travers des cavités connectées et favorise le glissement du glacier ou alors localisé à travers des chenaux et limite le glissement. Parallèlement, je montre que l’analyse de l’amplitude sismique permets d’étudier les crevasses, les variations d’épaisseur ou l’anisotropie de manière complémentaire aux analyses de phase sismique.Le premier résultat de ce travail transdisciplinaire est que la sismique passive peut être utiliser pour quantifier l'évolution temporelle des conditions de pression et de géométrie des chenaux sous-glaciaires sur une saison de fonte complète. Le second est qu’un réseau sismique dense peut être utiliser pour résoudre la configuration spatiale du drainage sous-glaciaire et la transition d'un réseau distribué à un réseau localisé. Ces avancées ouvrent à l’étude de tel processus sur d’autre sites tels les calottes Groenlandaise et Antarctique mais aussi à l’étude d’écoulements au sein de systèmes géophysiques tels les volcans, les karts ou les glissements de terrain

    Resolving subglacial hydrology network dynamics through seismic observations on an Alpine glacier

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    La façon dont l'eau s'écoule sous les glaciers joue un rôle majeur dans le couplage mécanique glace-roche qui définit les vitesses d’écoulement des glaciers. Aujourd'hui, notre compréhension de la physique de l'hydrologie sous-glaciaire est limitée et incertaine en raison de la rareté des mesures de terrain, qui ne représentent que partiellement l’hétérogénéité de l’environnement sous-glaciaire. L'objectif de mon doctorat est d'utiliser la sismologie passive pour surmonter les difficultés observationnelles et quantifier l’évolution des conditions de pression et de la configuration du réseau d’hydrologie sous glaciaire. De récents travaux montrent que l'écoulement turbulent d'eaux sous-glaciaire génère du bruit sismique dont l’étude donne accès aux propriétés hydrodynamique associées. Ces analyses ont été menées sur une courte période et il n’est pas certains qu’elles soient appropriées à l’étude de l’hydrologie sous-glaciaire sur les échelles de temps les plus représentative de son influence sur la dynamique glaciaire (saisonnières et diurnes). De plus, ces études ne considèrent pas de changements dans la configuration des réseaux hydrologique et il existe peu d’étude ayant localisé des sources de bruit sismique spatialement éparses et temporellement variables. Dans ce doctorat, j'aborde ces défis sismologiques afin de résoudre la dynamique de l'hydrologie sous-glaciaire.Nous avons acquis sur le glacier d'Argentière (Alpes) un jeu de données continu sur 2 ans permettant d’évaluer la puissance sismique induite par les flux d'eau sous-glaciaire et de la comparer à des mesures de la vitesse de glissement basale et du débit d'eau sous-glaciaire. Je montre que l'étude de la puissance sismique à [3-7] Hz donne accès aux propriétés l'hydrodynamique des flux d'eau sous-glaciaires sur des échelles de temps tant saisonnière qu’horaire et sur une gamme de débits de 0.25 à 10 m3/sec. Avec un cadre physique adéquat j'inverse, de ces observations, les gradients de pression et rayons hydrauliques associés et identifie une dynamique saisonnière des chenaux sous-glaciaire. À faible débit, les chenaux se comportent à l'équilibre et s'adaptent aux variations de débit par des changements de rayon hydraulique. À fort débit et forte variabilité diurne en apport d'eau, les chenaux se comportent hors équilibre et subissent de fortes variations du gradient de pression hydraulique qui maintiennent de fortes pression d'eau dans les cavités et favorisent des vitesses de glissement élevées.Nous avons mené une expérience d'un mois avec un réseau sismique dense, complétée par des mesures d'épaisseur et de vitesse de surface du glacier. Sur cette base j'ai développé une méthodologie pour relever le défi de localiser des sources de bruit sismique spatialement éparses et temporellement variables. Ce faisant, j'ai obtenu une carte du système de drainage sous-glaciaire ainsi que son évolution journalière. J’ai pu ainsi observer quand et où ce système est distribué à travers des cavités connectées et favorise le glissement du glacier ou alors localisé à travers des chenaux et limite le glissement. Parallèlement, je montre que l’analyse de l’amplitude sismique permets d’étudier les crevasses, les variations d’épaisseur ou l’anisotropie de manière complémentaire aux analyses de phase sismique.Le premier résultat de ce travail transdisciplinaire est que la sismique passive peut être utiliser pour quantifier l'évolution temporelle des conditions de pression et de géométrie des chenaux sous-glaciaires sur une saison de fonte complète. Le second est qu’un réseau sismique dense peut être utiliser pour résoudre la configuration spatiale du drainage sous-glaciaire et la transition d'un réseau distribué à un réseau localisé. Ces avancées ouvrent à l’étude de tel processus sur d’autre sites tels les calottes Groenlandaise et Antarctique mais aussi à l’étude d’écoulements au sein de systèmes géophysiques tels les volcans, les karts ou les glissements de terrain.The way in which water flows in the subglacial environment exerts a major control on ice-bed mechanical coupling, which strongly defines glacier sliding speeds. Today our understanding on the physics of the subglacial hydrology network is limited because of the scarcity of field measurements that yield a partial representation of the heterogeneous subglacial environment. The aim of my PhD work is to use passive seismology to help overcome common observational difficulties and quantify the evolution of the subglacial hydrology network pressure conditions and its configuration. Recent works show that subglacial turbulent water flow generates seismic noise that can be related to the associated hydrodynamics properties. These analyses were conducted over a limited period of time making it unclear whether such approach is appropriate to investigate seasonal and diurnal timescales, I.e. when subglacial water flow influences the most glacier dynamics. In addition, previous studies did not consider spatial changes in the heterogeneous drainage system, and until now, almost no study has located seismic noise sources spatially scattered and temporally varying. In this PhD work I address those seismological-challenges in order to resolve the subglacial hydrology dynamics in time and space.We acquired a 2-year long continuous dataset of subglacial-water-flow-induced seismic power as well as in-situ measured glacier basal sliding speed and subglacial water discharge from the Glacier d'Argentière (French Alps). I show that a careful investigation of the seismic power within [3-7] Hz can characterize the subglacial water flow hydrodynamics from seasonal to hourly timescales and across a wide range of water discharge (from 0.25 to 10 m3/sec). Combining such observations with adequate physical frameworks, I then inverted the associated hydraulic pressure gradient and hydraulic radii. I observed that the seasonal dynamics of subglacial channels is characterized by two distinct regimes. At low discharge, channels behave at equilibrium and accommodate variations in discharge mainly through changes in hydraulic radius. At a high discharge rate and with pronounced diurnal water-supply variability, channels behave out of equilibrium and undergo strong changes in the hydraulic pressure gradient, which may help sustain high water pressure in cavities and favor high glacier sliding speed over the summer.We then conducted a one-month long dense seismic-array experiment supplemented by glacier ice-thickness and surface velocity measurements. Using this unique dataset, I developed a novel methodology to overcome the challenge of locating seismic noise sources spatially scattered and temporally varying. Doing so, I successfully retrieve the first two-dimensional map of the subglacial drainage system as well as its day-to-day evolution. Using this map, I characterize when and where the subglacial drainage system is distributed through connected cavities, which favour rapid glacier flow versus localized through a channelized system that prevents rapid glacier flow. In addition, I also use high frequency seismic ground motion amplitude to study glacier features such as crevasses, thickness or ice anisotropy in a complementary way to what is traditionally done with seismic phase analysis.The first outcome of this cross-boundary PhD work is that one can analyse passive seismic measurements to retrieve the temporal evolution of subglacial channels pressure and geometry conditions over a complete melt-season. The second is that dense seismic array measurements can be used to resolve the subglacial drainage system spatial configuration and observe the switch from distributed to localized subglacial water flow. Such advances open the way for studying similar subglacial process on different sites and in particular in Greenland and Antarctica. This also concerns numerous sub-surface environment that host similar process such as volcanoes, karst, and landslides
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