Simulated distributions of the chlorofluorocarbons CFC-11 and CFC-12 are used to examine the vent... more Simulated distributions of the chlorofluorocarbons CFC-11 and CFC-12 are used to examine the ventilation of the North Atlantic Ocean in a global version of the Miami Isopycnic Coordinate Ocean Model (MICOM). Three simulations are performed: one with a diapycnal diffusivity K d = 3 × 10 −7 /N m 2 s −1 and an isopycnal diffusive velocity (i.e., diffusivity divided by the size of the grid cell) v trac = 0.01 m s −1 (Exp. 1); Exp. 2 is as Exp. 1 but with K d = 5 × 10 −8 /N m 2 s −1 plus increased bottom mixing; and Exp. 3 is as Exp. 2 but with v trac = 0.0025 m s −1. The main features of the simulated ventilation are strong uptake of the CFCs in the Labrador, Irminger and Nordic Seas, and a topographically aligned geostrophically controlled southward transport of CFC-enriched water in the Atlantic. It is found that the Overflow Waters (OW) from the Nordic Seas, the penetration of the western boundary currents, the ventilation of the subtropical surface waters, the vertical density stratification and the meridional overturning are all critically dependent on the applied isopycnal and diapycnal diffusivities, with Exp. 3 (Exp. 1) yielding the most (least) realistic results. Furthermore, it is the combined rather than the isolated effect of the isopycnal and diapycnal diffusivities that matter. For instance, the strength of the simulated Meridional Overturning Circulation (MOC) is similar in Exps. 1 and 3, but the simulated CFC-distributions are far too diffusive in Exp. 1 and fairly realistic in Exp. 3. It is demonstrated that the simulated distributions of transient tracers like the CFCs can be used to set the strength of the applied isopycnal mixing parameterization, a task that is difficult to conduct based on the simulated hydrography alone.
This study examines differences between patients with and without cancer in patient demographic a... more This study examines differences between patients with and without cancer in patient demographic and clinical characteristics and COVID-19 mortality and discusses the implications of these differences in relation to existing cancer disparities and COVID-19 vulnerabilities. Data was collected as a part of a retrospective study on a cohort of COVID-19 positive patients across Mount Sinai Health System from March 28, 2020 to April 26, 2020. Descriptive, comparative, and regression analyses were applied to examine differences between patients with and without cancer in demographic and clinical characteristics and COVID-19 mortality and whether cancer status predicts COVID-19 mortality controlling for these covariates using SAS 9.4. Results showed that, of 4641 patients who tested positive for COVID-19, 5.1% (N=236) had cancer. The median age of the total sample was 58 years (Q1-Q3: 41–71); 55.3% were male, 19.2% were current/former smokers, 6.1% were obese. The most commonly reported com...
Simulated distributions of the chlorofluorocarbons CFC-11 and CFC-12 are used to examine the vent... more Simulated distributions of the chlorofluorocarbons CFC-11 and CFC-12 are used to examine the ventilation of the North Atlantic Ocean in a global version of the Miami Isopycnic Coordinate Ocean Model (MICOM). Three simulations are performed: one with a diapycnal diffusivity K d = 3 × 10 −7 /N m 2 s −1 and an isopycnal diffusive velocity (i.e., diffusivity divided by the size of the grid cell) v trac = 0.01 m s −1 (Exp. 1); Exp. 2 is as Exp. 1 but with K d = 5 × 10 −8 /N m 2 s −1 plus increased bottom mixing; and Exp. 3 is as Exp. 2 but with v trac = 0.0025 m s −1. The main features of the simulated ventilation are strong uptake of the CFCs in the Labrador, Irminger and Nordic Seas, and a topographically aligned geostrophically controlled southward transport of CFC-enriched water in the Atlantic. It is found that the Overflow Waters (OW) from the Nordic Seas, the penetration of the western boundary currents, the ventilation of the subtropical surface waters, the vertical density stratification and the meridional overturning are all critically dependent on the applied isopycnal and diapycnal diffusivities, with Exp. 3 (Exp. 1) yielding the most (least) realistic results. Furthermore, it is the combined rather than the isolated effect of the isopycnal and diapycnal diffusivities that matter. For instance, the strength of the simulated Meridional Overturning Circulation (MOC) is similar in Exps. 1 and 3, but the simulated CFC-distributions are far too diffusive in Exp. 1 and fairly realistic in Exp. 3. It is demonstrated that the simulated distributions of transient tracers like the CFCs can be used to set the strength of the applied isopycnal mixing parameterization, a task that is difficult to conduct based on the simulated hydrography alone.
This study examines differences between patients with and without cancer in patient demographic a... more This study examines differences between patients with and without cancer in patient demographic and clinical characteristics and COVID-19 mortality and discusses the implications of these differences in relation to existing cancer disparities and COVID-19 vulnerabilities. Data was collected as a part of a retrospective study on a cohort of COVID-19 positive patients across Mount Sinai Health System from March 28, 2020 to April 26, 2020. Descriptive, comparative, and regression analyses were applied to examine differences between patients with and without cancer in demographic and clinical characteristics and COVID-19 mortality and whether cancer status predicts COVID-19 mortality controlling for these covariates using SAS 9.4. Results showed that, of 4641 patients who tested positive for COVID-19, 5.1% (N=236) had cancer. The median age of the total sample was 58 years (Q1-Q3: 41–71); 55.3% were male, 19.2% were current/former smokers, 6.1% were obese. The most commonly reported com...
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