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Medical planning for space exploration is based on the “floating” blood bank model to store life-saving red blood cells (RBCs) for emergencies. The “floating” blood bank approach is not sufficient in cases where multiple crewmembers are affected by space anemia. In these situations, long-term preserved RBCs will be vital to guarantee the health and safety of crew members. Transfusable RBC units can only be refrigerated for 42 days or frozen at -80 C. However, storing frozen RBCs at -80 C is challenging during the confined condition of long-duration space flight. Freeze-dried, viable RBCs would be an appropriate alternative because they can be stored without cooling, are predicted to have a shelf-life of years, and could be transfused immediately after rehydration. This study explores if freeze-dried RBCs can be rehydrated and transfused in reduced gravity with similar outcomes in recovery as observed at Earth gravity. Experiments analyzing freeze-dried RBC recoveries, rehydration fluid dynamics, and transfusion flow rates were analyzed utilizing an experimental glovebox in simulated 0 g during parabolic flights. RBC recoveries and rehydration fluid dynamics for volumes of 5 mL and 10 mL were the same in simulated 0 g compared to results obtained at 1 g. A clinically acceptable range of flow rates for slow intravenous infusion and rapid fluid resuscitation was possible with the simple augmentation of a hand-pumped clinical pressure bag around a unit of rehydrated RBCs. The results demonstrate the potential feasibility of using freeze-dried cells for healthcare during deep-space exploration. 

Purpose Three Coupled Model Intercomparison Project Phase 5 models involved in the G4 experiment of the Geoengineering Model Inter-comparison Project (GeoMIP) project were used to investigate the impact of stratospheric aerosol injection (SAI) on the mean surface air temperature and precipitation extremes in Africa. Design/methodology/approach This impact was examined under G4 and Representative Concentration Pathway (RCP) 4.5 scenarios on the total precipitation, the number of rainy days (RR1) and of days with heavy rainfall (R20 mm), the rainfall intensity (SDII), the maximum length of consecutive wet (CWD) and dry (CDD) days and on the maximum rainfall in five consecutive days (Rx5day) across four regions: Western Africa (WAF), Eastern Africa (EAF), Northern Africa and Southern Africa (SAF). Findings During the 50 years (2020–2069) of SAI, mean continental warming is −0.40°C lower in G4 than under RCP4.5. During the post-injection period (2070–2090), the temperature continues to increase, but at a lower rate (−0.19°C) than in RCP4.5. During SAI, annual rainfall in G4 is significantly greater than in RCP4.5 over the high latitudes (especially over SAF) and lower over the tropics. The termination of SAI leads to a significant increase of rainfall over Sahel and EAF and a decrease over SAF and Guinea Coast (WAF). Practical implications Compared to RCP4.5, SAI will contribute to reducing significantly regional warming but with a significant decrease of rainfall in the tropics where rainfed agriculture account for a large part of the economies. After the SAI period, the risk of drought over the extratropical regions (especially in SAF) will be mitigated, while the risk of floods will be exacerbated in the Central Sahel. Originality/value To meet the Paris Agreement, African countries will implement mitigation measures to contribute to keep the surface air temperature below 2°C. Geoengineering with SAI is suggested as an option to meet this challenge, but its implication on the African climate system needs a deep investigation in the aim to understand the impacts on temperature and precipitation extremes. To the best of the authors’ knowledge, this study is the first to investigate the potential impact of SAI using the G4 experiment of GeoMIP on temperature and precipitation extremes of the African continent. 

Abstract. The Geoengineering Model Intercomparison Project (GeoMIP) is a coordinating framework, started in 2010, that includes a series of standardized climate model experiments aimed at understanding the physical processes and projected impacts of solar geoengineering. Numerous experiments have been conducted, and numerous more have been proposed as “test-bed” experiments, spanning a variety of geoengineering techniques aimed at modifying the planetary radiation budget: stratospheric aerosol injection, marine cloud brightening, surface albedo modification, cirrus cloud thinning, and sunshade mirrors. To date, more than 100 studies have been published that used results from GeoMIP simulations. Here we provide a critical assessment of GeoMIP and its experiments. We discuss its successes and missed opportunities, for instance in terms of which experiments elicited more interest from the scientific community and which did not, and the potential reasons why that happened. We also discuss the knowledge that GeoMIP has contributed to the field of geoengineering research and climate science as a whole: what have we learned in terms of intermodel differences, robustness of the projected outcomes for specific geoengineering methods, and future areas of model development that would be necessary in the future? We also offer multiple examples of cases where GeoMIP experiments were fundamental for international assessments of climate change. Finally, we provide a series of recommendations, regarding both future experiments and more general activities, with the goal of continuously deepening our understanding of the effects of potential geoengineering approaches and reducing uncertainties in climate outcomes, important for assessing wider impacts on societies and ecosystems. In doing so, we refine the purpose of GeoMIP and outline a series of criteria whereby GeoMIP can best serve its participants, stakeholders, and the broader science community. 

Abstract Stratospheric aerosol geoengineering has been proposed as a potential solution to reduce climate change and its impacts. Here, we explore the responses of the Hadley circulation (HC) intensity and the intertropical convergence zone (ITCZ) using the strategic stratospheric aerosol geoengineering, in which sulfur dioxide was injected into the stratosphere at four different locations to maintain the global-mean surface temperature and the interhemispheric and equator-to-pole temperature gradients at present-day values (baseline). Simulations show that, relative to the baseline, strategic stratospheric aerosol geoengineering generally maintains northern winter December–January–February (DJF) HC intensity under RCP8.5, while it overcompensates for the greenhouse gas (GHG)-forced southern winter June–July–August (JJA) HC intensity increase, producing a 3.5 ± 0.4% weakening. The residual change of southern HC intensity in JJA is mainly associated with stratospheric heating and tropospheric temperature response due to enhanced stratospheric aerosol concentrations. Geoengineering overcompensates for the GHG-driven northward ITCZ shifts, producing 0.7° ± 0.1° and 0.2° ± 0.1° latitude southward migrations in JJA and DJF, respectively relative to the baseline. These migrations are affected by tropical interhemispheric temperature differences both at the surface and in the free troposphere. Further strategies for reducing the residual change of HC intensity and ITCZ shifts under stratospheric aerosol geoengineering could involve minimizing stratospheric heating and restoring and preserving the present-day tropical tropospheric interhemispheric temperature differences. 

T-cell therapies are rapidly emerging for treatment of cancer and other diseases but are limited by inefficient non-viral delivery methods. Acoustofluidic devices are in development to enhance non-viral delivery to cells. The effect of acoustofluidic parameters, such as channel geometry, on molecular loading in human T cells was assessed using 3D-printed acoustofluidic devices. Devices with rectilinear channels (1- and 2-mm diameters) were compared directly with concentric spiral channel geometries. Intracellular delivery of a fluorescent dye (calcein, 100 lg/ml) was evaluated in Jurkat T cells using flow cytometry after ultrasound treatment with cationic microbubbles (2.5% v/v). B-mode ultrasound pulses (2.5 MHz, 3.8 MPa output pressure) were generated by a P4-1 transducer on a Verasonics Vantage ultrasound system. Cell viability was assessed using propidum iodine staining (10 lg/ml). Intracellular molecular delivery was significantly enhanced with acoustofluidic treatment in each channel geometry, but treatment with the 1-mm concentric spiral geometry further enhanced delivery after acoustofluidic treatment compared to both 1- and 2-mm rectilinear channels (ANOVA p < 0.001, n ¼ 6/group). These results indicate that 3Dprinted acoustofluidic devices enhance molecular delivery to T cells, and channel geometry modulates intracellular loading efficiency. This approach may offer advantages to improve manufacturing of T cell therapies.