Standardization of molecular monitoring for chronic myeloid leukemia in Latin America using locally produced secondary cellular calibrators

Residual disease in chronic myeloid leukemia (CML) patients undergoing therapy with tyrosine kinase inhibitors (TKIs) is measured by assessing the quantity of transcripts of the BCR-ABL1 fusion gene in peripheral white blood cells. This analysis is based on reverse-transcription quantitative PCR (RT–qPCR) technology; however, the wide array of methods used worldwide has led to large variation in quantitative BCR-ABL1 measurements, which hamper inter-laboratory comparative studiesFil: Ruiz, María Sol. Fundación Cáncer. Centro de Investigaciones Oncológicas; ArgentinaFil: Medina, M.. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: Tapia, I.. Fundación Cáncer. Centro de Investigaciones Oncológicas; ArgentinaFil: Mordoh, Jose. Fundación Cáncer. Centro de Investigaciones Oncológicas; ArgentinaFil: Cross, N. C. P.. Universidad de Southampton Uk; Reino UnidoFil: Larripa, Irene Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: Bianchini, Michele. Fundación Cáncer. Centro de Investigaciones Oncológicas; Argentin

Na2.4Al0.4Mn2.6O7 anionic redox cathode material for sodium ion batteries- a combined experimental and theoretical approach to elucidate its charge storage mechanism

Here we report the synthesis via ceramic methods of the high-performance Mn-rich Na2.4Al0.4Mn2.6O7 oxygen-redox cathode material for Na-ion batteries which we use as a testbed material to study the effects of Al substitution and subsequent Na excess in the high-capacity, anionic redox-based cathode material Na2Mn3O7. The material shows a stable electrochemical performance, with a specific capacity of 200 mAh g-1 in the 1.5 - 4.7 voltage window at C/20 and capacity retention of 90 % after 40 cycles. Using a combination of electrochemical and structural analysis together with hybrid density functional theory calculations we explain the behaviour of this material with changes in Mn/anionic redox reactions and associated O2 release reactions occurring in the material during electrochemical cycling (Na insertion/extraction) and compare these findings to Na2Mn3O7. We expect that these results will advance understanding of the effect of dopants in Mn-rich cathode materials with oxygen redox activity to pave their way towards real applications in high-performing sodium-ion battery applications

Surface Engineering Strategy Using Urea To Improve the Rate Performance of Na2Ti3O7 in Na‐Ion Batteries

Na2Ti3O7 (NTO) is considered a promising anode material for Na‐ion batteries due to its layered structure with an open framework and low and safe average operating voltage of 0.3 V vs. Na+/Na. However, its poor electronic conductivity needs to be addressed to make this material attractive for practical applications among other anode choices. Here, we report a safe, controllable and affordable method using urea that significantly improves the rate performance of NTO by producing surface defects such as oxygen vacancies and hydroxyl groups, and the secondary phase Na2Ti6O13. The enhanced electrochemical performance agrees with the higher Na+ ion diffusion coefficient, higher charge carrier density and reduced bandgap observed in these samples, without the need of nanosizing and/or complex synthetic strategies. A comprehensive study using a combination of diffraction, microscopic, spectroscopic and electrochemical techniques supported by computational studies based on DFT calculations, was carried out to understand the effects of this treatment on the surface, chemistry and electronic and charge storage properties of NTO. This study underscores the benefits of using urea as a strategy for enhancing the charge storage properties of NTO and thus, unfolding the potential of this material in practical energy storage applications

Facile synthesis of organically synthesized porous carbon using a commercially available route with exceptional electrochemical performance

Organically synthesized porous carbon (OSPC) is a subclass of conjugated microporous polymer materials that have shown potential applications as anodes in ion batteries. However, a challenging, low-yielding, multistep synthetic route (the A method) has hindered further exploration of this exciting family. Here, OSPC-1 has been synthesized via an alternative, efficient one-pot method from commercially available reagents (the B method), hereafter referred to as OSPC-1b in contrast to OSPC-1a, where it is synthesized via the A method. Characterization revealed the same polymer structure and the highest surface area to date of an OSPC (or OSPC analogue) family member for OSPC-1b with 909 m2 g–1. OSPC-1b was tested as an anode for Li-ion batteries, demonstrating the same high capacity, fast charging, resistance to degradation, and inhibition of the formation of dangerous lithium dendrites as OSPC-1a. Furthermore, the electrochemical properties of OSPC-0 were evaluated for the first time, agreeing with previously predicted values, giving scope for the design and targeting of specific properties

Distortion product otoacoustic emissions in normally hearing subjects.

The finding of active function by the outer hair cells for sound processing prior to neural transduction in the inner hair cells represents the basic mechanism for the generation of Otoacoustic Emissions in the cochlea. Among them the so-called Distortion Product Otoacoustic Emissions represent a tool for an in depth knowledge of the Organ of Corti micromechanics, more advantageous than others, based on their properties, that makes possible an objective frequency-specific study: The response in a group of normally hearing subjects is presented and characterized to ascertain the basic features to be used in further testing of deaf people

Porous silica-pillared MXenes with controllable interlayer distances for long-life Na-ion batteries

MXenes are a recently discovered class of two-dimensional materials that have shown great potential as electrodes in electrochemical energy storage devices. Despite their promise in this area, MXenes can still suffer limitations in the form of restricted ion accessibility between the closely spaced multistacked MXene layers, causing low capacities and poor cycle life. Pillaring, a strategy where a secondary species is inserted between layers, has been used to increase interlayer spacings in clays with great success, but has had limited application in MXenes. We report a new amine-assisted pillaring methodology that successfully intercalates silica-based pillars between Ti3C2 layers. Using this technique, the interlayer spacing can be controlled with the choice of amine and calcination temperature, up to a maximum of 3.2 nm, the largest interlayer spacing reported for an MXene. Another effect of the pillaring is a dramatic increase in surface area, achieving BET surface areas of 235 m2 g-1, a sixty-fold increase over the unpillared material and the highest reported for MXenes using an intercalation-based method. The intercalation mechanism was revealed by different characterisation techniques, allowing the surface chemistry to be optimised for the pillaring process. The porous MXene was tested for Na-ion battery applications, and showed superior capacity, rate capability and remarkable stability compared with non-pillared materials, retaining 98.5% capacity between the 50th and 100th cycles. These results demonstrate the applicability and promise of pillaring techniques applied to MXenes, providing a new approach to optimising their properties for a range of applications. Porous MXenes are very promising materials for a range of applications including energy storage, conversion, catalysis and gas separations

Investigation of sodium insertion in hard carbon with operando small angle neutron scattering

Sodium-ion battery technology is a promising and more sustainable alternative to its more conventional lithium-ion based counterpart. The most common anode material for these systems is a disordered form of graphite known as hard carbon. The inherent disorder in these carbons results in multiple possible pathways for sodium storage making the characterisation of sodiation mechanisms during cycling highly challenging. Here, we report an operando small angle neutron scattering (SANS) investigation of sodiation in a commercial hard carbon using a custom electrochemical cell. We demonstrate that it is possible to discern different sodiation mechanisms throughout cycling and provide supporting evidence for a three-stage model in which sodium ions are first adsorbed onto the surface of particles, then intercalated into the graphene layers, and finally inserted into the nanopores during the electrochemical stage known as the plateau region. This study showcases the unique capabilities of operando SANS for the characterisation of sodiation mechanisms of carbon-based, disordered, porous materials

Nitrogen uptake and internal recycling in Zostera marina exposed to oyster farming: eelgrass potential as a natural biofilter

Oyster farming in estuaries and coastal lagoons frequently overlaps with the distribution of seagrass meadows, yet there are few studies on how this aquaculture practice affects seagrass physiology. We compared in situ nitrogen uptake and the productivity of Zostera marina shoots growing near off-bottom longlines and at a site not affected by oyster farming in San Quintin Bay, a coastal lagoon in Baja California, Mexico. We used benthic chambers to measure leaf NH4 (+) uptake capacities by pulse labeling with (NH4)-N-15 (+) and plant photosynthesis and respiration. The internal N-15 resorption/recycling was measured in shoots 2 weeks after incubations. The natural isotopic composition of eelgrass tissues and vegetative descriptors were also examined. Plants growing at the oyster farming site showed a higher leaf NH4 (+) uptake rate (33.1 mmol NH4 (+) m(-2) day(-1)) relative to those not exposed to oyster cultures (25.6 mmol NH4 (+) m(-2) day(-1)). We calculated that an eelgrass meadow of 15-16 ha (which represents only about 3-4 % of the subtidal eelgrass meadow cover in the western arm of the lagoon) can potentially incorporate the total amount of NH4 (+) excreted by oysters (similar to 5.2 x 10(6) mmol NH4 (+) day(-1)). This highlights the potential of eelgrass to act as a natural biofilter for the NH4 (+) produced by oyster farming. Shoots exposed to oysters were more efficient in re-utilizing the internal N-15 into the growth of new leaf tissues or to translocate it to belowground tissues. Photosynthetic rates were greater in shoots exposed to oysters, which is consistent with higher NH4 (+) uptake and less negative delta C-13 values. Vegetative production (shoot size, leaf growth) was also higher in these shoots. Aboveground/belowground biomass ratio was lower in eelgrass beds not directly influenced by oyster farms, likely related to the higher investment in belowground biomass to incorporate sedimentary nutrients

Electron paramagnetic resonance as a tool to determine the sodium charge storage mechanism of hard carbon

Hard carbon is a promising negative electrode material for rechargeable sodium-ion batteries due to the ready availability of their precursors and high reversible charge storage. The reaction mechanisms that drive the sodiation properties in hard carbons and subsequent electrochemical performance are strictly linked to the characteristic slope and plateau regions observed in the voltage profile of these materials. This work shows that electron paramagnetic resonance (EPR) spectroscopy is a powerful and fast diagnostic tool to predict the extent of the charge stored in the slope and plateau regions during galvanostatic tests in hard carbon materials. EPR lineshape simulation and temperature-dependent measurements help to separate the nature of the spins in mechanochemically modified hard carbon materials synthesised at different temperatures. This proves relationships between structure modification and electrochemical signatures in the galvanostatic curves to obtain information on their sodium storage mechanism. Furthermore, through ex situ EPR studies we study the evolution of these EPR signals at different states of charge to further elucidate the storage mechanisms in these carbons. Finally, we discuss the interrelationship between EPR spectroscopy data of the hard carbon samples studied and their corresponding charging storage mechanism