Understanding the Capacity Decay of Si/NMC622 Li-Ion Batteries Cycled in Superconcentrated Ionic Liquid Electrolytes: A New Perspective.

Silicon-containing Li-ion batteries have been the focus of many energy storage research efforts because of the promise of high energy density. Depending on the system, silicon generally demonstrates stable performance in half-cells, which is often attributed to the unlimited lithium supply from the lithium (Li) metal counter electrode. Here, the electrochemical performance of silicon with a high voltage NMC622 cathode was investigated in superconcentrated phosphonium-based ionic liquid (IL) electrolytes.

Traveling Ionospheric Disturbances in the Vicinity of Storm-Enhanced Density at Midlatitudes.

This study provides first storm time observations of the westward-propagating medium-scale traveling ionospheric disturbances (MSTIDs), particularly, associated with characteristic subauroral storm time features, storm-enhanced density (SED), subauroral polarization stream (SAPS), and enhanced thermospheric westward winds over the continental US. In the four recent (2017-2019) geomagnetic storm cases examined in this study (i.e.

Current Treatment Approaches and Global Consensus Guidelines for Brain Metastases in Melanoma.

Background: Up to 60% of melanoma patients develop melanoma brain metastases (MBM), which traditionally have a poor diagnosis. Current treatment strategies include immunotherapies (IO), targeted therapies (TT), and stereotactic radiosurgery (SRS), but there is considerable heterogeneity across worldwide consensus guidelines.

Objective: To summarize current treatments and compare worldwide guidelines for the treatment of MBM.

Morphological Evolution and Solid-Electrolyte Interphase Formation on LiNiMnCoO Cathodes Using Highly Concentrated Ionic Liquid Electrolytes.

Employing high-voltage Ni-rich cathodes in Li metal batteries (LMBs) requires stabilization of the electrode/electrolyte interfaces at both electrodes. A stable solid-electrolyte interphase (SEI) and suppression of active material pulverization remain the greatest challenges to achieving efficient long-term cycling. Herein, studies of NMC622 (1 mAh cm) cathodes were performed using highly concentrated -methyl--propylpyrrolidinium bis(fluorosulfonyl)imide (CmpyrFSI) 50 mol % lithium bis(fluorosulfonyl)imide (LiFSI) ionic liquid electrolyte (ILE).

Highly stable lithium anodes from recycled hemp textile.

Three-dimensional lithium (Li) hosts have been shown to suppress the growth of Li dendrites for next generation Li metal batteries. Here, we report a cost-effective and scalable approach to produce highly stable Li composite anodes from industrial hemp textile waste. The hemp@Li composite anodes demonstrate stable cycling both in half and full cells.

Cross-sectional associations between domain-specific sitting time and other lifestyle health behaviours: the Stormont study.

Background: There is a dearth of literature on how different domains of sitting time relate to other health behaviours. Therefore, this study aimed to explore these associations in a sample of office workers.

Methods: 7170 Northern Irish Civil Servants completed an online survey which included information on workday and non-workday sitting time in five domains (travel, work, TV, computer-use, leisure-time), physical activity, fruit and vegetable intake, alcohol consumption and cigarette smoking.

Tuning the Formation and Structure of the Silicon Electrode/Ionic Liquid Electrolyte Interphase in Superconcentrated Ionic Liquids.

The latest advances in the stabilization of Li/Na metal battery and Li-ion battery cycling have highlighted the importance of electrode/electrolyte interface [solid electrolyte interphase (SEI)] and its direct link to cycling behavior. To understand the structure and properties of the SEI, we used combined experimental and computational studies to unveil how the ionic liquid (IL) cation nature and salt concentration impact the silicon/IL electrolyte interfacial structure and the formed SEI. The nature of the IL cation is found to be important to control the electrolyte reductive decomposition that influences the SEI composition and properties and the reversibility of the Li-Si alloying process.

Solid-state rigid-rod polymer composite electrolytes with nanocrystalline lithium ion pathways.

A critical challenge for next-generation lithium-based batteries lies in development of electrolytes that enable thermal safety along with the use of high-energy-density electrodes. We describe molecular ionic composite electrolytes based on an aligned liquid crystalline polymer combined with ionic liquids and concentrated Li salt. This high strength (200 MPa) and non-flammable solid electrolyte possesses outstanding Li conductivity (1 mS cm at 25 °C) and electrochemical stability (5.

Compressively Stressed Silicon Nanoclusters as an Antifracture Mechanism for High-Performance Lithium-Ion Battery Anodes.

Silicon has been considered a good candidate for replacing the commonly used carbon anodes for lithium-ion batteries (LIBs) due to its high specific capacity, which can be up to 11 times higher than that of carbon. However, the desirable advantage that silicon brings to battery performance is currently overshadowed by its stress-induced performance loss and high electronic resistivity. The induced stress arises from two sources, namely, the deposition process (i.

Macrophase-Separated Organic Ionic Plastic Crystals/PAMPS-Based Ionomer Electrolyte: A New Design Perspective for Flexible and Highly Conductive Solid-State Electrolytes.

A material design approach was taken for the preparation of an organic ionic plastic crystal (OIPC)-polymer electrolyte material that exhibited both good mechanical and transport properties. Previous attempts to form this type of electrolyte material resulted in the solvation of the OIPC by the ionomer and loss of the plastic crystal component. Here, we prepared, in situ, a macrophase-separated OIPC-polymer electrolyte system by adding lithium bis(fluorosulfonyl)imide (LiFSI) to a (PAMPS-N) ionomer.

Toward High-Energy-Density Lithium Metal Batteries: Opportunities and Challenges for Solid Organic Electrolytes.

With increasing demands for safe, high capacity energy storage to support personal electronics, newer devices such as unmanned aerial vehicles, as well as the commercialization of electric vehicles, current energy storage technologies are facing increased challenges. Although alternative batteries have been intensively investigated, lithium (Li) batteries are still recognized as the preferred energy storage solution for the consumer electronics markets and next generation automobiles. However, the commercialized Li batteries still have disadvantages, such as low capacities, potential safety issues, and unfavorable cycling life.

Computer-assisted EEG diagnostic review for idiopathic generalized epilepsy.

Epilepsy diagnosis can be costly, time-consuming, and not uncommonly inaccurate. The reference standard diagnostic monitoring is continuous video-electroencephalography (EEG) monitoring, ideally capturing all events or concordant interictal discharges. Automating EEG data review would save time and resources, thus enabling more people to receive reference standard monitoring and also potentially heralding a more quantitative approach to therapeutic outcomes.

Cation effect on small phosphonium based ionic liquid electrolytes with high concentrations of lithium salt.

Ionic liquid electrolytes with high alkali salt concentrations have displayed some excellent electrochemical properties, thus opening up the field for further improvements to liquid electrolytes for lithium or sodium batteries. Fundamental computational investigations into these high concentration systems are required in order to gain a better understanding of these systems, yet they remain lacking. Small phosphonium-based ionic liquids with high concentrations of alkali metal ions have recently shown many promising results in experimental studies, thereby prompting us to conduct further theoretical exploration of these materials.

Biophysical basis of the linear electrical receptive fields of retinal ganglion cells.

Unlabelled: Responses of retinal ganglion cells to direct electrical stimulation have been shown experimentally to be well described by linear-nonlinear models. These models rely on the simplifying assumption that retinal ganglion cell responses to stimulation with an array of electrodes are driven by a simple linear weighted sum of stimulus current amplitudes from each electrode, known as the 'electrical receptive field'.

Objective: This paper aims to demonstrate the biophysical basis of the linear-nonlinear model and the electrical receptive field to facilitate the development of improved stimulation strategies for retinal implants.

Towards thermally stable high performance lithium-ion batteries: the combination of a phosphonium cation ionic liquid and a 3D porous molybdenum disulfide/graphene electrode.

We report a thermally stable high-performance lithium battery using an electrochemically synthesized three-dimensional porous molybdenum disulfide/graphene composite electrode and a phosphonium-based ionic liquid (IL) electrolyte. Benefiting from the structural merits of the chosen electrode and the thermal stability of the electrolyte, the cell coupled with a Li foil exhibits excellent rate performance and cycling capability at room temperature; and that is retained with an even better rate capability at an elevated temperature of 50 °C. This work may provide a new avenue for the development of safe and high performance lithium-ion batteries at high temperature.

Minimizing activation of overlying axons with epiretinal stimulation: The role of fiber orientation and electrode configuration.

Unlabelled: Currently, a challenge in electrical stimulation of the retina with a visual prosthesis (bionic eye) is to excite only the cells lying directly under the electrode in the ganglion cell layer, while avoiding excitation of axon bundles that pass over the surface of the retina in the nerve fiber layer. Stimulation of overlying axons results in irregular visual percepts, limiting perceptual efficacy. This research explores how differences in fiber orientation between the nerve fiber layer and ganglion cell layer leads to differences in the electrical activation of the axon initial segment and axons of passage.

A computational model of orientation-dependent activation of retinal ganglion cells.

Currently, a challenge in electrical stimulation for epiretinal prostheses is the avoidance of stimulation of axons of passage in the nerve fiber layer that originate from distant regions of the ganglion cell layer. A computational model of extracellular stimulation that captures the effect of neurite orientation in anisotropic tissue is developed using a modified version of the standard volume conductor model, known as the cellular composite model, embedded in a four layer model of the retina. Simulations are conducted to investigate the interaction of neural tissue orientation, electrode placement, and stimulation pulse duration and amplitude.

Knowledge and Skills of Healthcare Providers in Sub-Saharan Africa and Asia before and after Competency-Based Training in Emergency Obstetric and Early Newborn Care.

Background: Healthcare provider training in Emergency Obstetric and Newborn Care (EmOC&NC) is a component of 65% of intervention programs aimed at reducing maternal and newborn mortality and morbidity. It is important to evaluate the effectiveness of this.

Methods: We evaluated knowledge and skills among 5,939 healthcare providers before and after 3-5 days 'skills and drills' training in emergency obstetric and newborn care (EmOC&NC) conducted in 7 sub-Saharan Africa countries (Ghana, Kenya, Malawi, Nigeria, Sierra Leone, Tanzania, Zimbabwe) and 2 Asian countries (Bangladesh, Pakistan).

Underestimation of Pupil Size by Critical Care and Neurosurgical Nurses.

Background: Early detection of pupillary changes in patients with head injuries can alert the care team to increasing intracranial pressure. Previous research has shown inconsistencies in pupil measurement that are most likely due to the subjective nature of measuring pupils without the assistance of technology.

Objectives: To evaluate nurses' abilities to assess pupil diameter accurately and detect unequal pupils.

Lessons from 150 years of UK maternal hemorrhage deaths.

We have reviewed maternal hemorrhage death rates in the UK over the past 150 years in order to draw lessons from this material for current attempts to reduce global maternal mortality. Mortality rates from data in the UK Annual Reports from the Registrar General were entered into a database. Charts were created to display trends in hemorrhage mortality, allowing comparison with historical medical advances.

Work engagement and its association with occupational sitting time: results from the Stormont study.

Background: Evidence suggests that poor health outcomes and poor work-related health outcomes such as sickness presenteeism are associated with excessive sitting at work. Studies have yet to investigate the relationship between work engagement and occupational sitting. Work engagement is considered to be an important predictor of work-related well-being.

Descriptive epidemiology of domain-specific sitting in working adults: the Stormont Study.

Background: Given links between sedentary behaviour and unfavourable health outcomes, there is a need to understand the influence of socio-demographic factors on sedentary behaviour to inform effective interventions. This study examined domain-specific sitting times reported across socio-demographic groups of office workers.

Methods: The analyses are cross-sectional and based on a survey conducted within the Stormont Study, which is tracking employees in the Northern Ireland Civil Service.

Goal-directed control with cortical units that are gated by both top-down feedback and oscillatory coherence.

The brain is able to flexibly select behaviors that adapt to both its environment and its present goals. This cognitive control is understood to occur within the hierarchy of the cortex and relies strongly on the prefrontal and premotor cortices, which sit at the top of this hierarchy. Pyramidal neurons, the principal neurons in the cortex, have been observed to exhibit much stronger responses when they receive inputs at their soma/basal dendrites that are coincident with inputs at their apical dendrites.