Mathematical programming modelling tools for resource-poor countries and organisations

In recent years, powerful mathematical modelling languages have enabled Operational Research practitioners to rapidly develop prototype tools capable of modelling complex managerial decisions such as staff shift scheduling, or production and supply chain planning. However, such tools have often required expensive commercial optimisation solvers that are sometimes beyond the financial reach of small companies and organisations, particularly in the low-income and emerging economies. Fortunately, the worldwide scope of the internet has put powerful free optimisation tools within the reach of anyone with a modest PC and even a slow internet connection. This article will present examples showing just how beneficial such an approach can be for resource-poor organisations

Low serum sodium level during cardiopulmonary bypass predicts increased risk of postoperative stroke after coronary artery bypass graft surgery

ObjectiveRapid decreases in serum sodium levels are associated with altered mental status, seizures, and coma. During cardiac surgery, serum sodium levels decrease rapidly when cardiopulmonary bypass is initiated because cardiopulmonary bypass causes hemodilution. However, whether this decrease influences neurologic outcome after cardiac surgery remains unclear. We investigated whether the average serum sodium level during cardiopulmonary bypass is independently predictive of postoperative stroke or 30-day all-cause mortality in patients who undergo primary coronary artery bypass grafting.MethodsIn a single-institution, retrospective cohort of 2348 consecutive patients who underwent primary, isolated coronary artery bypass grafting, sequential multivariate logistic regression was performed to determine the threshold below which the average serum sodium level during cardiopulmonary bypass independently predicts postoperative stroke or early death. To further test the validity of this threshold and to control for selection bias, stepwise multivariate logistic regression was also performed on propensity score–matched patients (n = 924).ResultsAn average serum sodium level less than 130 mEq/L during cardiopulmonary bypass was independently predictive of stroke, both in the entire study cohort (1.44% vs 2.92%; odds ratio, 2.09; 95% confidence interval, 1.1-4.1; P = .03) and in the propensity-matched patients (0.9% vs 3.0%; odds ratio, 4.1; 95% confidence interval, 1.3-13.0; P = .02). The average serum sodium level during cardiopulmonary bypass was not independently associated with early death, regardless of what threshold value was used.ConclusionsAn average serum sodium level of less than 130 mEq/L during cardiopulmonary bypass is independently associated with an increased risk of postoperative stroke in patients who undergo primary coronary artery bypass grafting

Preface: Special Issue on Probing the Open Ocean With the Research Sailing Yacht Eugen Seibold for Climate Geochemistry

The 72‐foot sailing yacht Eugen Seibold is a new research platform for contamination‐free sampling of the water column and atmosphere for biological, chemical, and physical properties, and the exchange processes between the two realms. Ultimate goal of the project is a better understanding of the modern and past ocean and climate. Operations started in 2019 in the Northeast Atlantic, and will focus on the Tropical Eastern Pacific from 2023 until 2025. Laboratories for air and seawater analyses are equipped with down‐sized and automated state‐of‐the‐art technology for a comprehensive description of the marine carbon system including CO 2 concentration in the air and sea surface, pH, macro‐, and micro‐nutrient concentration (e.g., Fe, Cd), trace metals, and calcareous plankton. Air samples are obtained from ca. 13 m above sea surface and analyzed for particles (incl. black carbon and aerosols) and greenhouse gases. Plankton nets and seawater probes are deployed over the custom‐made A‐frame at the stern of the boat. Near Real‐Time Transfer of underway data via satellite connection allows dynamic expedition planning to maximize gain of information. Data and samples are analyzed in collaboration with the international expert research community. Quality controlled data are published for open access. The entire suite of data facilitates refined proxy calibration of paleoceanographic and paleoclimate archives at high temporal and spatial resolution in relation to seawater and atmospheric parameters. Plain Language Summary The new research sailing yacht Eugen Seibold ( ES ) enables clean, contamination‐free sampling of air and seawater to better understand the interactions between ocean and climate. For example, the oceans remove increasingly less carbon dioxide (CO 2 ) from the atmosphere the more saturated they are with CO 2 (ocean acidification). However, a detailed systematic understanding of air‐sea exchange processes remains to be developed. We analyze air and seawater as well as the exchange of greenhouse gases and other substances such as aerosols and soot (black carbon) between air and seawater at high resolution using modern materials and technologies. Scaled‐down, energy‐efficient, and automated probes developed over the past decade are being used to measure around 50 different characteristics of the marine environment. The work deck at the stern of the boat allows the use of custom‐made water samplers and plankton nets to study the ocean to below 1,000 m depth. In addition, the new data enables a better understanding of past ocean archives, such as the marine plankton accumulated in seafloor sediments, to reconstruct past climate changes. From 2019 to 2022, the S/Y ES sailed in the eastern North Atlantic and will operate in the tropical eastern Pacific until 2025. Key Points New research platform for contamination‐free sampling of the water column and atmosphere of biological, chemical, and physical properties Comprehensive marine geochemical analyzes including carbon (e.g., CO 2 ) in air and sea surface Proxy calibration of paleoclimate archives at high temporal and spatial resolution in relation to seawater and atmospheric parameter

JANUS: The Visible Camera Onboard the ESA JUICE Mission to the Jovian System

International audienceJANUS is the camera selected by ESA as the visible imager of the JUICE mission, focusing on the three icy Galilean satellites and the Jupiter atmosphere

JANUS: The Visible Camera Onboard the ESA JUICE Mission to the Jovian System

JANUS is the camera selected by ESA as the visible imager of the JUICE mission, focusing on the three icy Galilean satellites and the Jupiter atmosphere

JANUS: The Visible Camera Onboard the ESA JUICE Mission to the Jovian System

International audienceJANUS is the camera selected by ESA as the visible imager of the JUICE mission, focusing on the three icy Galilean satellites and the Jupiter atmosphere