523 research outputs found

    THE MIDDLE TRIASSIC OF THE BREMBANA VALLEY: PRELIMINARY STUDY OF THE ESINO PLATFORM (Bergamasc Alps)

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    The stratigraphy and paleogeography of the ladinian Esino Limestone outcropping in Valle Brembana-Valle Parina, have been integrated with the biostratigraphic analysis of cephalopod fauna. A complex internal structure of the upper anisian-ladinian Esino carbonate platform has been identified. Six different lithozones have been recognized, they record the stratigraphic-paleogeographic evolution of the Esino Limestone. This carbonate platform developed through three stages: 1) construction of a lower edifice (Late Anisian-? Early Ladinian) representing the first phase of carbonate piatform diffusion on structural highs, which were already the site of carbonate deposition during the Middle Anisian (peritidal dolomites of the Angolo Limestone); 2) buildup of the carbonate complex (main edifice). In this second phase (Early Ladinian-Late Ladinian p.p.) the most important one, the platform growth took place by prevalent aggradation; 3) development of the upper edifice and progradation of the piatform in the Late Ladinian. In this third phase, inner plarform facies with diagenetic caps at the top of peritidal cycles are common. The buildup developed in the second phase yields bioclastic packstones with ammonoids, gastropods, echinoderms, and bivalves clustered within lithozone 4 and in the proximity of the southern margin of the platform in Val Parina. Studies in progress of ammonoids and gastropods allowed for the recognition of different fossil assemblages which date from Early Ladinian to Late Ladinian. A few problematic ammonoid assemblage of probably Early Ladinian age, has been found in a stratigraphic level above the base of the Esino Limestone

    Large-scale progradation, demise and rebirth of a high-relief carbonate platform (Triassic, Lombardy Southern Alps, Italy)

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    The Upper Anisian to Early Carnian succession of the Middle Val Brembana-Pegherolo Massif (Central Southern Alps of Italy) records a complete depositional cycle from platform inception to growth, demise and rebirth. The depositional architecture of this system reflects different evolutionary stages: an inception stage which postdates a previous drowning of an Anisian carbonate platform with progradation of the carbonate platform from the nucleation areas, an aggradational stage with increasing water depth in the basins, a progradational stage where steep slopes composed of margin-derived breccias develop and a final crisis corresponding to the subaerial exposure of the platform top, followed by the deposition of shales in the basin before the rebirth of a different type of carbonate factory. The record of this evolution reflects the effects of the change in accommodation space (interplay of subsidence and eustacy), which controls the type and storage sites of the sediments produced by the carbonate factory. The effects of the changes in accommodation space are recorded in the shallow water platform as well as in the intraplatform basins, where the sediments, delivered at different rates from the platform top are stored. As a consequence, the aggradational stage corresponds to reduced sedimentation in the basins (i.e. sediments are stored on the platform top) whereas during progradation resedimented limestones are more common in the basin. Subaerial exposure rapidly halted the carbonate production on the platform top, while a major input of shales (probably reflecting a climate change and/or lowering of the base level) is recorded in the basin, where shales onlap the slope of the previous carbonate system. The rebirth of the carbonate factory after subaerial exposure of the platform top is characterized by a different composition of the carbonate factory, probably reflecting changes of the environmental conditions. The step-by-step recording of the evolution of the carbonate system represents a unique opportunity to record a seismic-scale complete evolutionary cycle of a carbonate system in its different sub-environments, from the platform top to the basin

    Chemo-Biostratigraphic characterization of the Triassic/Jurassic boundary interval in the Western Southern Alps

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    The latemost Triassic was marked by a major mass extinction event, following profound global environmental changes likely related to the activity of the Central Atlantic Magmatic Province (CAMP), including: i) rapid sea-level fluctuations, ii) perturbations of the global C cycle, iii) and the collapse of the carbonate biological factory. Several studies tempted to stratigraphically constrain this global event and reconstruct the causative dynamics behind this dramatic extinction. In this work, we investigated the freshly-caved Italcementi active Quarry section, outcropping on the Mt. Albenza (Lombardy Basin, Southern Alps, Italy), for organic and carbonate carbon isotopes and calcareous nannofossils, contributing to the stratigrafic and paleoceanographic characterization of the end- Triassic interval. The new isotopic data highlight the occurrence of three 13C anomalies, which have been demostrated to be of global significance and to correspond to: 1) the late Rhaetian \u201cprecursor Carbon Isotope Excursion (CIE)\u201d; 2) the latemost Rhaetian \u201cinitial negative CIE\u201d; 3) and the Early Jurassic \u201cmain CIE\u201d. These excursions likely correspond to different phases of the CAMP volcanism probably responsible for perturbations in the ocean-atmoshpere system. We identify changes in nannofossil abundance and composition in correspondence of these intervals. In particular, a turnover is detected in correspondence of the \u201cinitial negative CIE\u201d with the first occurrence of Jurassic species coinciding with the end of the 13C anomaly thus being at a lower stratigraphic level than found in other localities worldwide. Further analyses are therefore required to cast light on this new evidence

    Effect of dialysis membrane and patient's age on signs of dialysis-related amyloidosis

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    Effect of dialysis membrane and patient's age on signs of dialysis-related amyloidosis. This 12 center study was designed to assess factors affecting the development and progression of β2-microglobulin amyloidosis in long-term dialysis. A total of 221 patients who were on hemodialysis for more than five years, and who were treated the entire time only with AN69, a biocompatible, highly permeable membrane, or cuprophane, a less permeable, poorly biocompatible membrane (Cell) were evaluated for time on dialysis, development of carpal tunnel syndrome, and cystic bone lesions X-ray documentation was taken in a minimum of four of the six following joints: both hips, wrists and shoulders. The data demonstrate that patients treated solely by AN69 membranes display signs of bone amyloidosis less frequently than do those treated by Cell membranes. Age at onset of dialysis was found to have a striking correlation with the development of carpal tunnel syndrome and bone amyloidosis, while no significant influence was found for hyperparathyroidism, sex or year of first dialysis

    Eliminating viral hepatitis C in Belgium: the micro-elimination approach

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    Background: Hepatitis C virus is one of the leading causes of chronic liver disease and liver-related deaths worldwide. The estimated prevalence of chronic hepatitis C viral infection among the general Belgian population was 0.57% (n = 64,000) in 2015. Although Belgium has had a ‘Hepatitis C Plan’ since 2014, elimination efforts are unclear. This study employs the best available data and modelling estimates to define the burden of hepatitis C viral infection among key subgroups in Belgium, identify information gaps and propose potential approaches to screening, linkage to care and treatment, and cure. Methods: We examined the peer-reviewed and grey literature since 2012 for data on the prevalence of hepatitis C viral infection in Belgium in key subgroups identified by national experts and in the literature. Ultimately, this research is primarily based on data provided by the key stakeholders themselves due to a lack of reliable data in the literature. Based on this, we modelled the treatment rates required to reach elimination of hepatitis C in several subgroups. Results: Eleven potential subgroups were identified. There were no data available for two subgroups: generational cohorts and men who have sex with men. In six subgroups, fewer than 3000 people were reported or estimated to have hepatitis C infection. Migrants and people who inject drugs were the most affected subgroups, and children were the least affected subgroup. Only two subgroups are on target to achieve elimination by 2030: patients living with haemophilia and transplant recipients. Conclusions: Removing Belgian treatment reimbursement restrictions in January 2019 was a big step towards eliminating HCV. In addition, increasing surveillance, including with a national registry, treatment prescription by other health-care providers and availability of treatment in local pharmacies are central to improving the current situation and getting on track to reach the 2030 WHO hepatitis C elimination targets in Belgium

    The Micro-Elimination Approach to Eliminating Hepatitis C:Strategic and Operational Considerations

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    The introduction of efficacious new hepatitis C virus (HCV) treatments galvanized the World Health Organization to define ambitious targets for eliminating HCV as a public health threat by 2030. Formidable obstacles to reaching this goal can best be overcome through a micro-elimination approach, which entails pursuing elimination goals in discrete populations through multi-stakeholder initiatives that tailor interventions to the needs of these populations. Micro-elimination is less daunting, less complex, and less costly than full-scale, country-level initiatives to eliminate HCV, and it can build momentum by producing small victories that inspire more ambitious efforts. The micro-elimination approach encourages stakeholders who are most knowledgeable about specific populations to engage with each other and also promotes the uptake of new models of care. Examples of micro-elimination target populations include medical patients, people who inject drugs, migrants, and prisoners, although candidate populations can be expected to vary greatly in different countries and subnational areas

    Sedimentary context and palaeoecology of Gigantoproductus shell beds in the Mississippian Eyam Limestone Formation, Derbyshire carbonate platform, central England

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    A sedimentological study was conducted at two localities exposing the Mississippian Eyam Limestone Formation of the Derbyshire carbonate platform, UK. Ricklow Quarry comprises seven facies with diverse skeletal assemblages, representing deposition on the inner to middle ramp within open marine waters. Once-a-Week Quarry comprises four facies, dominated by crinoidal debris representing deposition on the inner ramp. Both localities expose Gigantoproductus shell beds. Palaeoecological analysis of a single shell bed from each locality enabled investigation of the rapid colonization and success of this taxon on the platform. At Ricklow Quarry, on the eastern side of a localized mud mound, both life (>72% of thin and thick-shelled brachiopods in life position) and neighbourhood assemblages are present. A low-moderate diversity community (<1.37 and <0.8 Shannon diversity index) rapidly established over relict Brigantian mud mounds. Shell beds are preluded by intervals of decreased energy that allowed larvae to settle. Once established, the dominance of thick-shelled individuals enabled baffling, potentially providing localized shelter for larvae and nearby individuals. At Once-a-Week Quarry, where no mud mound is present, only thick-shelled Gigantoproductus species and a low diversity community (<1.07 Shannon diversity index) exclusively comprising neighbourhood assemblages (37% in life position) is present. The presence of inactive mud mounds at Ricklow Quarry appears to have been the key to the success of Gigantoproductus species enabling the onset of stable communities in the shelter provided by the relict mound. Once the first palaeocommunities were established, larvae dispersed and colonized higher energy settings, such as at Once-a-Week Quarry

    Patient and Caregiver Priorities for Outcomes in CKD: A Multinational Nominal Group Technique Study

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    RATIONALE & OBJECTIVE: Patients with chronic kidney disease (CKD) are at an increased risk for premature death, cardiovascular disease, and burdensome symptoms that impair quality of life. We aimed to identify patient and caregiver priorities for outcomes in CKD. STUDY DESIGN: Focus groups with nominal group technique. SETTING & PARTICIPANTS: Adult patients with CKD (all stages) and caregivers in the United States, Australia, and United Kingdom. ANALYTICAL APPROACH: Participants identified, ranked, and discussed outcomes that were important during the stages of CKD before kidney replacement therapy. For each outcome, we calculated a mean importance score (scale, 0-1). Qualitative data were analyzed using thematic analysis. RESULTS: 67 (54 patients, 13 caregivers) participated in 10 groups and identified 36 outcomes. The 5 top-ranked outcomes for patients were kidney function (importance score, 0.42), end-stage kidney disease (0.29), fatigue (0.26), mortality (0.25), and life participation (0.20); and for caregivers, the top 5 outcomes were life participation (importance score, 0.38), kidney function (0.37), mortality (0.23), fatigue (0.21), and anxiety (0.20). Blood pressure, cognition, and depression were consistently ranked in the top 10 outcomes across role (patient/caregiver), country, and treatment stage. Five themes were identified: re-evaluating and reframing life, intensified kidney consciousness, battling unrelenting and debilitating burdens, dreading upheaval and constraints, and taboo and unspoken concerns. LIMITATIONS: Only English-speaking participants were included. CONCLUSIONS: Patients and caregivers gave highest priority to kidney function, mortality, fatigue, life participation, anxiety, and depression. Consistent reporting of these outcomes in research may inform shared decision making based on patient and caregiver priorities in CKD
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