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Generative artificial intelligence methods are employed for the first time to construct a surrogate model for plasma turbulence that enables long-time transport simulations. The proposed GAIT (Generative Artificial Intelligence Turbulence) model is based on the coupling of a convolutional variational autoencoder that encodes precomputed turbulence data into a reduced latent space, and a recurrent neural network and decoder that generate new turbulence states 400 times faster than the direct numerical integration. The model is applied to the Hasegawa-Wakatani (HW) plasma turbulence model, which is closely related to the quasigeostrophic model used in geophysical fluid dynamics. Very good agreement is found between the GAIT and the HW models in the spatiotemporal Fourier and Proper Orthogonal Decomposition spectra, and the flow topology characterized by the Okubo-Weiss decomposition. The GAIT model also reproduces Lagrangian transport including the probability distribution function of particle displacements and the effective turbulent diffusivity.

The use of neutron reflectors is an effective method for improving the quality of neutron sources and neutron delivery systems. In this work, we further develop the method based on the Bragg scattering of neutrons in crystals with large interplanar distances. We compare samples of differently prepared fluorine intercalated graphites by measuring the total cross section for the interaction of neutrons with the samples, depending on the neutron wavelength. The Brag scattering cross section is expected to be the dominant part of the total cross section in all the cases. The results show that all samples provide high reflection efficiency over the entire range of the so-called "neutron reflectivity gap" and beyond it, and that they also allow for the choosing of the optimal intercalation methods.

Background: The Golden Hour Box (GHB), an iceless blood container designed for transfusion closest to the point of injury, is used by military medical teams in remote damage control resuscitation. While its performance is well-established in hot environments, it remains underexplored in cold conditions, a significant consideration in emerging global conflict zones., Study Design and Methods: Four GHBs were preconditioned at +4°C or +18°C for 8 h and subsequently exposed to controlled laboratory simulated temperatures of -5, -15, and -25°C for 100 h. The study focused on their capability to maintain an internal temperature between +2 and +6°C, the recommended range for red blood cells unit storage and transport, using calibrated sensors for precise monitoring., Results: When exposed to negative Celsius temperatures, GHBs showed varied performance depending on preconditioning temperatures. When preconditioned at +4°C, GHBs maintained an internal temperature within the target range (+2 to +6°C) for 100 h at -5°C, 52 ± 1 h at -15°C, and 29 ± 4 h at -25°C. In contrast, the internal temperature of GHBs preconditioned at +18°C exceeded this range in less than 30 min, then dropped below 2°C more rapidly than those preconditioned at +4°C, occurring within 20 ± 2 h at -15 and 13 ± 1 h at -25°C., Conclusion: The GHB, when properly preconditioned, effectively maintains internal temperatures suitable for blood product transport in extreme cold. Future research, including analyses of blood performances, is still needed to validate these results in more realistic operational conditions for use in cold environments., (© 2024 AABB.)

Both nanometer-sized CuO and MgO particles exhibit bactericidal activities against Staphylococcus aureus and Escherichia coli , two bacteria causing healthcare-associated infections. The solid solution Cu 1- x Mg x O is potentially interesting for biomedical applications as one of the compositions could have a much higher bactericidal activity than the parent CuO and MgO oxides considered separately. But, to date, no Vegard's law proves the real existence of such a solid solution. This study was aimed at shedding light on the solubility of Mg 2+ ions in CuO nanoparticles and its impact on the free oxygen radicals they produce, the quantity of which determines their bactericidal performance. The solid solution Cu 1- x Mg x O does exist and particles were synthesized as nanorods of 50-60 nm length by thermally decomposing at 400 °C the single source precursors Cu 1- x Mg x (OH) 2 . Vegard's laws exist only in the compositional range 0 ≤ x ≤ 0.1, due to the low capacity of the distorted NaCl-type structure to accommodate regular coordination [MgO 6 ] octahedra. Only neutron diffraction allowed the detection of the small amount of MgO nanoparticles present as impurity in a 10 g sample beyond the solubility limit of x = 0.1. In this series, CuO nanorods remain the most active against E. coli and S. aureus with reduction in viability of 99.998% and 98.7% after 180 min in water, respectively. Our synthesis route has significantly increased the activity of pure CuO nanoparticles beyond the values reported so far, especially against E. coli . The bactericidal performances of CuO and the magnesium-substituted counterparts ( i.e. Cu 1- x Mg x O) are not linked to cupric ions they release in water since their mass concentrations after 180 min are much lower than minimal concentrations inhibiting the growth of E. coli and S. aureus . These CuO nanorods kill bacteria in water because they produce a large quantity of free oxygen radicals in the presence of H 2 O 2 only, the majority of which are highly toxic HO˙ radicals. Mg 2+ ions have a detrimental effect on this production, thus explaining the lowest bactericidal performance of Cu 1- x Mg x O nanorods. Definitive knowledge of the toxicity of Cu 1- x Mg x O nanoparticles towards bacteria in water is now available.

To date, there is still a lack of definite knowledge regarding the toxicity of Cu(OH) 2 nanoparticles towards bacteria. This study was aimed at shedding light on the role played by released cupric ions in the toxicity of nanoparticles. To address this issue, the bactericidal activity of Cu(OH) 2 was at first evaluated in sterile water, a medium in which particles are not soluble. In parallel, an isovalent substitution of cupric ions by Mg 2+ was attempted in the crystal structure of Cu(OH) 2 nanoparticles to increase their solubility and determine the impact on the bactericidal activity. For the first time, mixed Cu 1- x Mg x (OH) 2 nanorods ( x ≤ 0.1) of about 15 nm in diameter and a few hundred nanometers in length were successfully prepared by a simple co-precipitation at room temperature in mixed alkaline (NaOH/Na 2 CO 3 ) medium. For E. coli , 100% reduction of one million CFU per mL (6 log 10 ) occurs after only 180 min on contact with both Cu(OH) 2 and Cu 0.9 Mg 0.1 (OH) 2 nanorods. The entire initial inoculum of S. aureus is also killed by Cu(OH) 2 after 180 min (100% or 6 log 10 reduction), while 0.01% of these bacteria stay alive on contact with Cu 0.9 Mg 0.1 (OH) 2 (99.99% or 4 log 10 reduction). The bactericidal performances of Cu(OH) 2 and the magnesium-substituted counterparts ( i.e. Cu 1- x Mg x (OH) 2 ) are not linked to cupric ions they release in water since their mass concentrations after 180 min are much lower than minimal concentrations inhibiting the growth of E. coli and S. aureus . Finally, an EPR spin trapping study reveals how these nanorods kill bacteria in water: only the presence of hydrogen peroxide, a by-product of the normal metabolism of oxygen in aerobic bacteria, allows the Cu(OH) 2 and its magnesium-substituted counterparts to produce a lethal amount of free radicals, the majority of which are the highly toxic HO˙.

Copper substitution together with nano-structuring are applied with the aim to increase the bactericidal performances of the rocksalt-type MgO oxide. The partial substitution of magnesium ions with Cu 2+ has been successfully achieved in both micrometer- and nanometer-sized particles of MgO up to 20 mol% in increments of 5 mol%. Microstructural analyses using the Integral Breadth method revealed that the thermal decomposition of the single source precursor Mg 1-x Cu x (OH) 2-2y (CO 3 ) y .zH 2 O at 400 °C creates numerous defects in 10-20 nm-sized particles of Mg 1-x Cu x O thus obtained. These defects make the surface of nanoparticles highly reactive towards the sorption of water molecules, to the extent that the cubic cell a parameter in as-prepared Mg 1-x Cu x O expands by +0.24% as soon as the nanoparticles are exposed to ambient air (60% RH). The hydration of Mg 1-x Cu x O particles in liquid water is based on a conventional dissolution-precipitation mechanism. Particles of a few microns in size dissolve all the more slowly the higher the copper content and only Mg(OH) 2 starts precipitating after 3 h. In contrast, the dissolution of all 10-20 nm-sized Mg 1-x Cu x O particles is complete over a 3 h period and water suspension only contains 4-12 nm-sized Mg 1-x Cu x (OH) 2 particles after 3 h. Thereby, the bactericidal activity reported for water suspension of Mg 1-x Cu x O nanoparticles depends on the speed at which these nanoparticles dissolve and Mg 1-x Cu x (OH) 2 nanoparticles precipitate in the first 3 h. Only 10 mol% of cupric ions in MgO nanoparticles are sufficient to kill both E. coli and S. aureus with a bactericidal kinetics faster and reductions in viability at 3 h (6.5 Log 10 and 2.7 Log 10 , respectively) higher than the conventional antibacterial agent CuO (4.7 Log 10 and 2 Log 10 under the same conditions). EPR spin trapping study reveals that "hydroxylated" Mg 0.9 Cu 0.1 O as well as Mg 0.9 Cu 0.1 (OH) 2 nanoparticles produce more spin-adducts with highly toxic hydroxyl radicals than their copper-free counterparts. The rapid mass adsorption of Mg 0.9 Cu 0.1 (OH) 2 nanoparticles onto the cell envelopes following their precipitation together with their ability to produce Reactive Oxygen Species are responsible for the exceptionally high bactericidal activity measured in the course of the hydroxylation of Mg 0.9 Cu 0.1 O nanoparticles., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Brucite Mg(OH) 2 belongs to a family of two-dimensional compounds with a CdI 2 -type structure built up from layers of edge-sharing octahedra delineating 2D galleries. In the current study, nanometer-sized platelets of copper substituted Mg(OH) 2 were prepared by co-precipitation at room temperature in mixed alkaline (NaOH/Na 2 CO 3 ) medium. Very weak substitution of a few hydroxyl ions by carbonate groups was highlighted at first by infrared spectroscopy and then quantified by thermogravimetric (TG) and mass spectrometric (MS) evolved gas analyses. The presence in a very low amount of water molecules in the galleries induces disorder in the stacking of layers of edge-sharing octahedra along the c-axis. The dehydration of the hydroxides taking place below 225 °C preserves the brucite-type structure of the samples while suppressing the stacking disorder. Copper substitution greatly enhances the bactericidal activity of nanometer-sized platelets of brucite against two bacteria frequently involved in healthcare-associated-infections. 10 mol% of cupric ions in Mg(OH) 2 (a copper loading of 0.102 mg mL -1 in the suspension) were sufficient to induce, after 3 h in contact, 100% and 99.3% reductions in viability of Gram-negative E. coli and Gram-positive S. aureus, respectively (reductions as low as 23% and 48% are reported for the parent compound Mg(OH) 2 in the same conditions). A good compromise between fast bactericidal kinetics and a high reduction in viability is reached by the 15 mol% copper-substituted Mg(OH) 2 hydroxide. Its use gives the opportunity to five-fold reduce the copper loading of the bactericidal agent while being at least equally or even more efficient compared to the conventional CuO (a Cu loading of 0.799 mg mL -1 and 0.154 mg mL -1 in the suspension of CuO and 15 mol% copper substituted Mg(OH) 2 particles, respectively).

Background: Life-threatening situations requiring blood transfusion under extreme conditions or in remote and austere locations, such as the battlefield or in traffic accidents, would benefit from reliable blood typing practices that are easily understood by a nonscientist or nonlaboratory technician and provide quick results., Study Design and Methods: A simplified protocol was developed for the lateral flow-based device MDmulticard ABO-D-Rh subgroups-K. Its performance was compared to a reference method (PK7300, Beckman Coulter) in native blood samples from donors. The method was tested on blood samples stressed in vitro as a model of hemorrhage cases (through hemodilution using physiologic serum) and dehydration (through hemoconcentration by removing an aliquot of plasma after centrifugation), respectively., Results: A total of 146 tests were performed on 52 samples; 126 in the hemodilution group (42 for each native, diluted 1/2, and diluted 1/4 samples) and 20 in the hemoconcentration group (10 for each native and 10% concentrated samples). Hematocrit in the tested samples ranged from 9.8% to 57.6% while hemoglobin levels ranged from 3.2 to 20.1 g/dL. The phenotype profile detected with the MDmulticard using the simplified protocol resulted in 22 A, seven B, 20 O, and three AB, of which nine were D- and five were Kell positive. No discrepancies were found with respect to the results obtained with the reference method., Conclusion: The simplified protocol for MDmulticard use could be considered a reliable method for blood typing in extreme environment or emergency situations, worsened by red blood cell dilution or concentration., (© 2017 AABB.)

Using the French Hemovigilance Network database from 2007 to 2013, we provide information on demographics, incidence, and risk factors of reported transfusion-related acute lung injury (TRALI) and possible TRALI, analyze TRALI mitigation efforts for fresh frozen plasma and platelet concentrates, and consider the impact of platelet additive solutions on TRALI incidence. We applied the Toronto consensus conference definitions for TRALI and possible TRALI. Two TRALI subgroups were considered: "antibody positive" when a donor has human leukocyte antigen (class I or II) and/or human neutrophil antigen antibodies and the recipient has cognate antigen, and "antibody negative" when immunological investigation is negative or not done. The analysis targeted 378 cases, divided into antibody-positive TRALI (n=75), antibody-negative TRALI (n=100), and possible TRALI (n=203). TRALI patients were younger and received more blood components than the general population of transfused patients. Moreover, we identified the following clinical conditions where patients seemed to be at higher risk to develop TRALI: postpartum hemorrhage, acute myeloid leukemia, liver transplantation, allogeneic and autologous hematopoietic stem cells transplantation, polytrauma, and thrombotic microangiopathy. Policy measures intended to reduce antibody-positive TRALI were found effective for apheresis platelet concentrates and fresh frozen plasma but not for whole blood-derived platelet concentrates. The use of platelet additive solutions was associated with a significant reduction in the incidence of TRALI following transfusion of buffy coat-derived platelet concentrates but not following transfusion of apheresis platelets. Our data reinforce the concept that possible TRALI and TRALI, as defined in the Canadian consensus conference, share many characteristics. No specific policy measures are currently directed at mitigation of possible TRALI despite its impact on transfusion safety. Despite TRALI mitigation measures, the overall incidence of TRALI cases reported to the French Hemovigilance system was not significantly reduced. Therefore, additional research is needed to reduce, if not eradicate, all TRALI categories., (Copyright © 2017 Elsevier Inc. All rights reserved.)