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1.
Sci Rep ; 12(1): 10777, 2022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35750743

RESUMO

We report on the ash cloud related to the gravitational collapse of a portion of the Stromboli volcano crater rim that occurred on 19 May 2021. The collapse produced a pyroclastic density current (PDC) that spread along the northwest flank of the volcano and propagated in the sea for about 1 km. The PDC was associated with a convective ash cloud that rapidly dispersed eastward and deposited a thin layer (< 1 mm) of very fine pinkish ash over the village of Stromboli. The deposit was sampled shortly after the emplacement (within a few hours) and prior to any significant reworking or re-sedimentation. We present a comprehensive description of the deposit including dispersal, sedimentological characteristics and textural and geochemical features. We also compare the 19 May 2021 deposit with fine-ash deposits connected to other PDCs and landslides previously occurring at Stromboli and with the distal ash of a paroxysmal explosive eruption of Mt. Etna volcano. Results indicate that the distributions of the mass on the ground and of the grain size are not correlated with the distance from the source. Also, the componentry reflects a preponderance of remobilized material ingested by the PDC. Therefore, the great amount of fine ash can be ascribed to clasts comminution processes, although the prevalence of dense crystalline components records an overall equiaxial shape, revealing a paucity of elongated clast with complex morphology. Furthermore, the outcomes of this work aim to create a collection of data of a co-PDC ash cloud that may prove useful for comparison with other deposits worldwide.


Assuntos
Erupções Vulcânicas , Itália
2.
Sci Rep ; 10(1): 17357, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33060646

RESUMO

Stromboli volcano (Italy), always active with low energy explosive activity, is a very attractive place for visitors, scientists, and inhabitants of the island. Nevertheless, occasional more intense eruptions can present a serious danger. This study focuses on the modeling and estimation of their inter-event time and temporal rate. With this aim we constructed a new historical catalog of major explosions and paroxysms through a detailed review of scientific literature of the last ca. 140 years. The catalog includes the calendar date and phenomena descriptions for 180 explosive events, of which 36 were paroxysms. We evaluated the impact of the main sources of uncertainty affecting the historical catalog. In particular, we categorized as uncertain 45 major explosions that reportedly occurred before 1985 and tested the effect of excluding these events from our analysis. Moreover, after analyzing the entire record in the period [1879, 2020], we separately considered, as sequences, events in [1879, 1960] and in [1985, 2020] because of possible under recording issues in the period [1960, 1985]. Our new models quantify the temporal rate of major explosions and paroxysms as a function of time passed since the last event occurred. Recurrence hazard levels are found to be significantly elevated in the weeks and months following a major explosion or paroxysm, and then gradually decrease over longer periods. Computed hazard functions are also used to illustrate a methodology for estimating order-of-magnitude individual risk of fatality under certain basis conditions. This study represents a first quantitatively formal advance in determining long-term hazard levels at Stromboli.

3.
G Ital Cardiol (Rome) ; 20(11): 671-684, 2019 Nov.
Artigo em Italiano | MEDLINE | ID: mdl-31697276

RESUMO

Acute myocardial infarction, stroke, peripheral arterial disease and pulmonary embolism share thrombosis as a common mechanism. Some well-known risk factors for arterial thromboembolism are recognized as "weak risk factors" of venous one, too. Arterial and venous thrombosis share also some pathophysiological mechanisms, including inflammation, endothelial damage, and hypercoagulability. It is likely, thus, that any disease related to arterial and venous thrombosis belong to the same "pan-vascular syndrome", that constitutes itself a chronic, recurrent inflammatory disease. According to the available data, there are elements for implementing an omni-comprehensive cardiovascular evaluation after an episode of venous thromboembolism, requiring the investigations, in addition to the known unrecognized prothrombotic conditions, also of indirect signs and risk factors for a possible arterial thromboembolic event. Large, prospective studies are needed to establish the more appropriate therapeutic strategies in this context.The aim of the present statement is to make aware all the physicians involved in the management of arterial and venous diseases and to provide some tools for evaluating the implications of related major risk factors. Thus, it could be possible to lay the foundation for a reduction of total cardiovascular risk, in terms of primary and secondary prevention of arterial and venous thromboembolism.


Assuntos
Doenças Cardiovasculares/etiologia , Tromboembolia/complicações , Tromboembolia Venosa/complicações , Doenças Cardiovasculares/prevenção & controle , Humanos , Prevenção Primária/métodos , Fatores de Risco , Prevenção Secundária/métodos , Tromboembolia/prevenção & controle , Tromboembolia/terapia , Tromboembolia Venosa/prevenção & controle , Tromboembolia Venosa/terapia
4.
Eur Heart J Suppl ; 19(Suppl D): D3-D54, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28751833

RESUMO

Atherosclerotic cardiovascular disease still represents the leading cause of death in Western countries. A wealth of scientific evidence demonstrates that increased blood cholesterol levels have a major impact on the outbreak and progression of atherosclerotic plaques. Moreover, several cholesterol-lowering pharmacological agents, including statins and ezetimibe, have proved effective in improving clinical outcomes. This document focuses on the clinical management of hypercholesterolaemia and has been conceived by 16 Italian medical associations with the support of the Italian National Institute of Health. The authors discuss in detail the role of hypercholesterolaemia in the genesis of atherosclerotic cardiovascular disease. In addition, the implications for high cholesterol levels in the definition of the individual cardiovascular risk profile have been carefully analysed, while all available therapeutic options for blood cholesterol reduction and cardiovascular risk mitigation have been explored. Finally, this document outlines the diagnostic and therapeutic pathways for the clinical management of patients with hypercholesterolaemia.

5.
Sci Rep ; 7(1): 4805, 2017 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-28684730

RESUMO

In December 2015, four violent explosive episodes from Mt. Etna's oldest summit crater, the Voragine, produced eruptive columns extending up to 15 km a.s.l. and significant fallout of tephra up to a hundred km from the vent. A combined textural and compositional study was carried out on pyroclasts from three of the four tephra deposits sampled on the volcano at 6 to 14 km from the crater. Ash fractions (Φ = 1-2) were investigated because these grain sizes preserve the magma properties unmodified by post- emplacement processes. Results were used to identify processes occurring in the conduit during each single paroxysm and to understand how they evolve throughout the eruptive period. Results indicate that the magmatic column is strongly heterogeneous, mainly with respect to microlite, vescicle content and melt composition. During each episode, the heterogeneities can develop at time scales as short as a few tens of hours, and differences between distinct episodes indicate that the time scale for completely refilling the system and renewing magma is in the same order of magnitude. Our data also confirm that the number and shape of microlites, together with melt composition, have a strong control on rheological properties and fragmentation style.

6.
Eur Heart J Suppl ; 19(Suppl D): D163-D189, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28533729

RESUMO

Stable coronary artery disease (CAD) is a clinical entity of great epidemiological importance. It is becoming increasingly common due to the longer life expectancy, being strictly related to age and to advances in diagnostic techniques and pharmacological and non-pharmacological interventions. Stable CAD encompasses a variety of clinical and anatomic presentations, making the identification of its clinical and anatomical features challenging. Therapeutic interventions should be defined on an individual basis according to the patient's risk profile. To this aim, management flow charts have been reviewed based on sustainability and appropriateness derived from recent evidence. Special emphasis has been placed on non-pharmacological interventions, stressing the importance of lifestyle changes, including smoking cessation, regular physical activity, and diet. Adherence to therapy as an emerging risk factor is also discussed.

7.
G Ital Cardiol (Rome) ; 18(3 Suppl 1): 3S-16S, 2017 Mar.
Artigo em Italiano | MEDLINE | ID: mdl-28492564

RESUMO

For patients with stable coronary artery disease (SCAD), either after hospitalization for acute cardiac events or in the chronic phase, comprehensive treatment programs should be devoted to: (i) reducing mortality and major adverse cardiovascular events, (ii) reducing the ischemic burden and related symptoms, and (iii) increasing exercise capacity and quality of life.Heart rate (HR) has demonstrated to have prognostic value and patients beyond the limit of 70 bpm display increased risk of all the above adverse outcomes, even after adjustment for parameters such as the extension of myocardial infarction and the presence of heart failure. It is well known that a sustained HR elevation may contribute to the pathogenesis of SCAD, being the likelihood of developing ischemia, plaque instability, trigger for arrhythmias, increased vascular oxidative stress, and endothelial dysfunction the mechanisms resulting in this effect. Moreover, high HR could promote chronotropic incompetence, leading to functional disability and reduced quality of life.Despite the strong relationship between HR and prognosis, there is heterogeneity among current guidelines in considering HR as a formal therapeutic target for secondary prevention in SCAD, as far as the cut-off limit. This expert opinion document considered major trials and observational registries in the modern treatment era with beta-blockers and ivabradine, suggesting that an adequate HR control could represent a target for (i), (ii), and (iii) therapeutic goals in SCAD patients with systolic dysfunction (with major evidence for reduced left ventricular ejection fraction <40%), and a target for (ii) and (iii) goals in SCAD patients with preserved left ventricular ejection fraction. The defined cut-off limit is 70 bpm. To date, there is room for improvement of HR control, since in contemporary SCAD patients HR values <70 bpm are present in less than half of cases, even in the vulnerable phase after an acute coronary syndrome.


Assuntos
Síndrome Coronariana Aguda/fisiopatologia , Síndrome Coronariana Aguda/terapia , Doença das Coronárias/fisiopatologia , Doença das Coronárias/terapia , Frequência Cardíaca , Algoritmos , Doença Crônica , Humanos , Prognóstico
8.
G Ital Cardiol (Rome) ; 17(7-8): 529-69, 2016.
Artigo em Italiano | MEDLINE | ID: mdl-27571333

RESUMO

Stable coronary artery disease is of epidemiological importance. It is becoming increasingly common due to the longer life expectancy, being strictly related to age and to advances in diagnostic techniques and pharmacological and non-pharmacological interventions.Stable coronary artery disease encompasses a variety of clinical and anatomic presentations, making the identification of its clinical and anatomical features challenging. Therapeutic interventions should be defined on an individual basis according to the patient's risk profile. To this aim, management flow-charts have been reviewed based on sustainability and appropriateness derived from recent evidence. Special emphasis has been placed on non-pharmacological interventions, stressing the importance of lifestyle changes, including smoking cessation, regular physical activity and diet. Adherence to therapy as an emerging risk factor is also discussed.


Assuntos
Angioplastia Coronária com Balão , Ponte de Artéria Coronária , Doença da Artéria Coronariana/terapia , Antagonistas Adrenérgicos/uso terapêutico , Angioplastia Coronária com Balão/métodos , Anti-Inflamatórios não Esteroides/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Fármacos Cardiovasculares/uso terapêutico , Ponte de Artéria Coronária/métodos , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/prevenção & controle , Quimioterapia Combinada , Humanos , Itália/epidemiologia , Cooperação do Paciente , Inibidores da Agregação Plaquetária/uso terapêutico , Índice de Gravidade de Doença , Resultado do Tratamento
9.
G Ital Cardiol (Rome) ; 17(6 Suppl 1): 3S-57, 2016 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-27312138

RESUMO

Atherosclerotic cardiovascular disease still represents the leading cause of death in western countries. A wealth of scientific evidence demonstrates that increased blood cholesterol levels have a major impact on the outbreak and progression of atherosclerotic plaques. Moreover, several cholesterol-lowering pharmacological agents, including statins and ezetimibe, have proven effective in improving clinical outcomes. This document is focused on the clinical management of hypercholesterolemia and has been conceived by 16 Italian medical associations with the support of the Italian National Institute of Health. The authors have considered with particular attention the role of hypercholesterolemia in the genesis of atherosclerotic cardiovascular disease. Besides, the implications of high cholesterol levels in the definition of the individual cardiovascular risk profile have been carefully analyzed, while all available therapeutic options for blood cholesterol reduction and cardiovascular risk mitigation have been considered. Finally, this document outlines the diagnostic and therapeutic pathways for the clinical management of patients with hypercholesterolemia.


Assuntos
Doenças Cardiovasculares/epidemiologia , Hipercolesterolemia/diagnóstico , Anticolesterolemiantes/uso terapêutico , Consenso , Humanos , Hipercolesterolemia/complicações , Hipercolesterolemia/tratamento farmacológico , Itália , Fatores de Risco
10.
Sci Rep ; 4: 5851, 2014 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-25069064

RESUMO

Deposits of mid-intensity basaltic explosive eruptions are characterized by the coexistence of different types of juvenile clasts, which show a large variability of external properties and texture, reflecting alternatively the effects of primary processes related to magma storage or ascent, or of syn-eruptive modifications occurred during or immediately after their ejection. If fragments fall back within the crater area before being re-ejected during the ensuing activity, they are subject to thermally- and chemically-induced alterations. These 'recycled' clasts can be considered as cognate lithic for the eruption/explosion they derive. Their exact identification has consequences for a correct interpretation of eruption dynamics, with important implications for hazard assessment. On ash erupted during selected basaltic eruptions (at Stromboli, Etna, Vesuvius, Gaua-Vanuatu), we have identified a set of characteristics that can be associated with the occurrence of intra-crater recycling processes, based also on the comparison with results of reheating experiments performed on primary juvenile material, at variable temperature and under different redox conditions.

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