5 research outputs found
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A new perspective of the climatological features of upper-level cut-off lows in the Southern Hemisphere
This study presents a detailed view of the seasonal variability of upper-level cut-off lows (COLs) in the Southern Hemisphere. The COLs are identified and tracked using data from a 36-year period of the European Centre for Medium Range Weather Forecast reanalysis (ERA-Interim). The objective identification of the COLs uses a new approach, which is based on 300 hPa relative vorticity minima, and three restrictive criteria of the presence of a cold-core, stratospheric potential vorticity intrusion, and cut-off cyclonic circulation. The highest COL activity is in agreement with previous studies, located near three main continental areas (Australia, South America, and Africa), with maximum frequencies usually observed in the austral autumn. The COL mean intensity values show a marked seasonal and spatial variation, with maximum (minimum) values during the austral winter (summer), a unique feature that has not been observed previously in studies based on the geopotential. The link between intensity and lysis is examined, and finds that weaker systems are more susceptible to lysis in the vicinity of the Andes Cordillera, associated with the topographic Rossby wave. Lysis and genesis regions are close to each other, confirming that COLs are quasi-stationary systems. Also, COLs tend to move eastward and are faster over the higher latitudes. The mean growth/decay rates coincide with the major genesis and lysis density regions, such as the significant decay values across the Andes all year. As a consequence of using vorticity for the tracking method a longer lifetime of COLs is detected than in other studies, but this does not affect the total frequency of occurrence. Comparisons with other studies suggest that the differences in seasonality are due to uncertainties in the reanalyses and the methods used to identify COLs
Global overview of the management of acute cholecystitis during the COVID-19 pandemic (CHOLECOVID study)
Background: This study provides a global overview of the management of patients with acute cholecystitis during the initial phase of the COVID-19 pandemic. Methods: CHOLECOVID is an international, multicentre, observational comparative study of patients admitted to hospital with acute cholecystitis during the COVID-19 pandemic. Data on management were collected for a 2-month study interval coincident with the WHO declaration of the SARS-CoV-2 pandemic and compared with an equivalent pre-pandemic time interval. Mediation analysis examined the influence of SARS-COV-2 infection on 30-day mortality. Results: This study collected data on 9783 patients with acute cholecystitis admitted to 247 hospitals across the world. The pandemic was associated with reduced availability of surgical workforce and operating facilities globally, a significant shift to worse severity of disease, and increased use of conservative management. There was a reduction (both absolute and proportionate) in the number of patients undergoing cholecystectomy from 3095 patients (56.2 per cent) pre-pandemic to 1998 patients (46.2 per cent) during the pandemic but there was no difference in 30-day all-cause mortality after cholecystectomy comparing the pre-pandemic interval with the pandemic (13 patients (0.4 per cent) pre-pandemic to 13 patients (0.6 per cent) pandemic; P = 0.355). In mediation analysis, an admission with acute cholecystitis during the pandemic was associated with a non-significant increased risk of death (OR 1.29, 95 per cent c.i. 0.93 to 1.79, P = 0.121). Conclusion: CHOLECOVID provides a unique overview of the treatment of patients with cholecystitis across the globe during the first months of the SARS-CoV-2 pandemic. The study highlights the need for system resilience in retention of elective surgical activity. Cholecystectomy was associated with a low risk of mortality and deferral of treatment results in an increase in avoidable morbidity that represents the non-COVID cost of this pandemic
Towards an operational anthropogenic CO2 emissions monitoring and verification support capacity
Under the Paris Agreement progress of emission reduction efforts is tracked on the basis of regular updates to national Greenhouse Gas (GHG) inventories, referred to as bottom-up estimates. However, only top-down atmospheric measurements can provide observation-based evidence of emission trends. Today there is no internationally agreed, operational capacity to monitor anthropogenic GHG emission trends using atmospheric measurements to complement national bottom-up inventories.
The European Commission (EC), the European Space Agency, the European Centre for Medium-Range Weather Forecasts, the European Organisation for the Exploitation of Meteorological Satellites and international experts, are joining forces to develop such an operational capacity for monitoring anthropogenic CO2 emissions as a new CO2 service under EC's Copernicus Programme. Design studies have been used to translate identified needs into defined requirements and functionalities of this anthropogenic CO2 emissions Monitoring and Verification Support (CO2MVS) capacity. It adopts a holistic view and includes components such as atmospheric space-borne and in-situ measurements, bottom-up CO2 emission maps, improved modeling of the carbon cycle, an operational data-assimilation system integrating top-down and bottom-up information, and a policy-relevant decision support tool.
The CO2MVS capacity with operational capabilities by 2026, is expected to visualize regular updates of global CO2 emissions, likely at 0.05°x0.05°. This will complement the PAâs enhanced transparency framework, providing actionable information on anthropogenic CO2 emissions that are the main driver of climate change. This information will be available to all stakeholders, including governments and citizens, allowing them to reflect on trends and effectiveness of reduction measures. The new EC gave green light to pass the CO2MVS from exploratory to implementing phase.JRC.D.6-Knowledge for Sustainable Development and Food Securit
Global overview of the management of acute cholecystitis during the COVID-19 pandemic (CHOLECOVID study)
Background: This study provides a global overview of the management of patients with acute cholecystitis during the initial phase of the COVID-19 pandemic. Methods: CHOLECOVID is an international, multicentre, observational comparative study of patients admitted to hospital with acute cholecystitis during the COVID-19 pandemic. Data on management were collected for a 2-month study interval coincident with the WHO declaration of the SARS-CoV-2 pandemic and compared with an equivalent pre-pandemic time interval. Mediation analysis examined the influence of SARS-COV-2 infection on 30-day mortality. Results: This study collected data on 9783 patients with acute cholecystitis admitted to 247 hospitals across the world. The pandemic was associated with reduced availability of surgical workforce and operating facilities globally, a significant shift to worse severity of disease, and increased use of conservative management. There was a reduction (both absolute and proportionate) in the number of patients undergoing cholecystectomy from 3095 patients (56.2 per cent) pre-pandemic to 1998 patients (46.2 per cent) during the pandemic but there was no difference in 30-day all-cause mortality after cholecystectomy comparing the pre-pandemic interval with the pandemic (13 patients (0.4 per cent) pre-pandemic to 13 patients (0.6 per cent) pandemic; Pâ=â0.355). In mediation analysis, an admission with acute cholecystitis during the pandemic was associated with a non-significant increased risk of death (OR 1.29, 95 per cent c.i. 0.93 to 1.79, Pâ=â0.121). Conclusion: CHOLECOVID provides a unique overview of the treatment of patients with cholecystitis across the globe during the first months of the SARS-CoV-2 pandemic. The study highlights the need for system resilience in retention of elective surgical activity. Cholecystectomy was associated with a low risk of mortality and deferral of treatment results in an increase in avoidable morbidity that represents the non-COVID cost of this pandemic