Scalable Dry Process for Fabricating a Na Superionic Conductor-Type Solid Electrolyte Sheet.

The cost reduction and mass production of oxide-based solid electrolytes are critical for the commercialization of all-solid-state batteries. In this study, an environmentally friendly, low-cost, and high-density oxide-based Na superionic conductor-type solid electrolyte sheet was fabricated via a dry process without the use of any solvent. The polytetrafluoroethylene (PTFE), used as a binder, was transformed into thin thread-like structures via shear force, resulting in a flexible solid electrolyte sheet. The solid electrolyte powder quantity was limited to 50 wt % for fabricating a uniform green sheet via the wet process. However, when the dry process was employed for green sheet fabrication, the solid electrolyte powder quantity could be increased to values exceeding 95 wt %. Therefore, the green sheets produced by using the dry process demonstrated a higher density than those fabricated by using the wet process. The binder content and particle size affected the ionic conductivity of a solid electrolyte sheet fabricated via a dry process. The sheet obtained via the blending of 3 wt % PTFE binder with a solid electrolyte powder, finely ground using a planetary ball mill, which exhibited the highest total ionic conductivity of 1.03 mS cm-1.

A Novel High-Performance TiO2-x /TiO1-y Ny Coating Material for Silicon Anode in Lithium-Ion Batteries.

Protective surface coatings on Si anodes are promising for improving the electrochemical performance of lithium-ion batteries (LIBs). Nevertheless, most coating materials have severe issues, including low initial coulombic efficiency, structural fracture, morphology control, and complicated synthetic processing. In this study, a multifunctional TiO2- x /TiO1- y Ny (TTN) formed via a facile and scalable synthetic process is applied as a coating material for Si anodes. A thin layer of amorphous TiO2 is uniformly coated onto Si nanoparticles by a simple sol-gel method and then converted into a two phase TiO2- x /TiO1- y Ny via nitridation. The lithiated TiO2-x provides high ionic and electrical conductivity, while TiO1-y Ny can improve mechanical strength that alleviates volume change of Si to address capacity fading issue. Owing to these synergetic advantages, TiO2- x /TiO1- y Ny -coated Si (Si@TTN) exhibits excellent electrochemical properties, including a high charge capacity of 1650 mA h g-1 at 0.1 A g-1 and 84% capacity retention after 100 cycles at 1 A g-1 . Moreover, a significantly enhanced rate performance can be achieved at a high current density. This investigation presents a facile and effective coating material to use as the high-capacity silicon anode in the emerging Si anode technology in LIBs.

Achieving Cycling Stability in Anode of Lithium-Ion Batteries with Silicon-Embedded Titanium Oxynitride Microsphere.

Surface coating approaches for silicon (Si) have demonstrated potential for use as anodes in lithium-ion batteries (LIBs) to address the large volume change and low conductivity of Si. However, the practical application of these approaches remains a challenge because they do not effectively accommodate the pulverization of Si during cycling or require complex processes. Herein, Si-embedded titanium oxynitride (Si-TiON) was proposed and successfully fabricated using a spray-drying process. TiON can be uniformly coated on the Si surface via self-assembly, which can enhance the Si utilization and electrode stability. This is because TiON exhibits high mechanical strength and electrical conductivity, allowing it to act as a rigid and electrically conductive matrix. As a result, the Si-TiON electrodes delivered an initial reversible capacity of 1663 mA h g-1 with remarkably enhanced capacity retention and rate performance.

A Strategic Approach to Use Upcycled Si Nanomaterials for Stable Operation of Lithium-Ion Batteries.

Silicon, as a promising next-generation anode material, has drawn special attention from industries due to its high theoretical capacity (around 3600 mAh g-1) in comparison with conventional electrodes, e.g., graphite. However, the fast capacity fading resulted by a large volume change hinders the pragmatic use of Si anodes for lithium ion batteries. In this work, we propose an efficient strategy to improve the cyclability of upcycled Si nanomaterials through a simple battery operation protocol. When the utilization degree of Si electrodes was decreased, the electrode deformation was significantly alleviated. This directly led to an excellent electrochemical performance over 100 cycles. In addition, the average charge (delithation) voltage was shifted to a lower voltage, when the utilization degree of electrodes was controlled. These results demonstrated that our strategic approach would be an effective way to enhance the electrochemical performance of Si anodes and improve the cost-effectiveness of scaling-up the decent nanostructured Si material.

Microalgae-Templated Spray Drying for Hierarchical and Porous Fe3O4/C Composite Microspheres as Li-ion Battery Anode Materials.

A method of microalgae-templated spray drying to develop hierarchical porous Fe3O4/C composite microspheres as anode materials for Li-ion batteries was developed. During the spray-drying process, individual microalgae serve as building blocks of raspberry-like hollow microspheres via self-assembly. In the present study, microalgae-derived carbon matrices, naturally doped heteroatoms, and hierarchical porous structural features synergistically contributed to the high electrochemical performance of the Fe3O4/C composite microspheres, enabling a discharge capacity of 1375 mA·h·g-1 after 700 cycles at a current density of 1 A/g. Notably, the microalgal frameworks of the Fe3O4/C composite microspheres were maintained over the course of charge/discharge cycling, thus demonstrating the structural stability of the composite microspheres against pulverization. In contrast, the sample fabricated without microalgal templating showed significant capacity drops (up to ~40% of initial capacity) during the early cycles. Clearly, templating of microalgae endows anode materials with superior cycling stability.

Hierarchically Well-Developed Porous Graphene Nanofibers Comprising N-Doped Graphitic C-Coated Cobalt Oxide Hollow Nanospheres As Anodes for High-Rate Li-Ion Batteries.

Hierarchically well-developed porous graphene nanofibers comprising N-doped graphitic C (NGC)-coated cobalt oxide hollow nanospheres are introduced as anodes for high-rate Li-ion batteries. For this, three strategies, comprising the Kirkendall effect, metal-organic frameworks, and compositing with highly conductive C, are applied to the 1D architecture. In particular, NGC layers are coated on cobalt oxide hollow nanospheres as a primary transport path of electrons followed by graphene-nanonetwork-constituting nanofibers as a continuous and secondary electron transport path. Superior cycling performance is achieved, as the unique nanostructure delivers a discharge capacity of 823 mAh g-1 after 500 cycles at 3.0 A g-1 with a low decay rate of 0.092% per cycle. The rate capability is also noteworthy as the structure exhibits high discharge capacities of 1035, 929, 847, 787, 747, 703, 672, 650, 625, 610, 570, 537, 475, 422, 294, and 222 mAh g-1 at current densities of 0.5, 1.5, 3, 5, 7, 10, 12, 15, 18, 20, 25, 30, 40, 50, 80, and 100 A g-1 , respectively. In view of the highly efficient Li+ ion/electron diffusion and high structural stability, the present nanostructuring strategy has a huge potential in opening new frontiers for high-rate and long-lived stable energy storage systems.

Prevalence of attention deficit hyperactivity disorder symptoms in narcolepsy: a systematic review.

OBJECTIVE: Narcolepsy is characterized by excessive daytime sleepiness and cataplexy. Attention deficit hyperactivity disorder (ADHD) is characterized by hyperactivity, inattention, and impulsivity. However, despite their differences, both narcolepsy and ADHD share the symptoms of sleep disturbance and excessive daytime sleepiness. Recent studies have suggested a link between the two disorders. The objective of systematic review was to assess the prevalence of ADHD symptoms in narcolepsy. METHODS: We performed a systematic search of MEDLINE (inception to December 2018) and EMBASE (inception to December 2018) for English publications of human studies using the keywords "narcolepsy" and "ADHD". RESULTS: Five studies examining a total of 328 patients met the eligibility criteria for this study examining the prevalence of ADHD symptoms in narcolepsy. The pooled prevalence of ADHD symptoms in narcolepsy was 33.0%. Two studies using the international classification of sleep disorders, second edition (ICSD-2) observed a pooled prevalence of ADHD symptoms in narcolepsy of 25.0%, while two other studies that relied on the ICSD-3 criteria observed a pooled prevalence of ADHD symptoms in narcolepsy of 36.4%. CONCLUSIONS: The prevalence of ADHD symptoms was >30%, making it an important comorbidity of narcolepsy. Future studies should be performed to better assess the relationship between ADHD and narcolepsy.

Pattern formation of metal-oxide hybrid nanostructures via the self-assembly of di-block copolymer blends.

The templated self-assembly of block copolymers (BCPs) with a high Flory-Huggins interaction parameter (χ) can effectively create ultrafine, well-ordered nanostructures in the range of 5-30 nm. However, the self-assembled BCP patterns remain limited to possible morphological geometries and materials. Here, we introduce a novel and useful self-assembly method of di-BCP blends capable of generating diverse hybrid nanostructures consisting of oxide and metal materials through the rapid microphase separation of A-B/B-C BCP blends. We successfully obtained various hybridized BCP morphologies which cannot be acquired from a single di-BCP, such as hexagonally arranged hybrid dot and dot-in-hole patterns by controlling the mixing ratios of the solvents with a binary solvent annealing process. Furthermore, we demonstrate how the binary solvent vapor annealing process can provide a wide range of pattern geometries to di-BCP blends, showing a well-defined spontaneous one-to-one accommodation in dot-in-hole nanostructures. Specifically, we show clearly how the self-assembled BCPs can be functionalized via selective reduction and/or an oxidation process, resulting in the excellent positioning of confined silica nanodots into each nanospace of a Pt mesh. These results suggest a new method to achieve the pattern formation of more diverse and complex hybrid nanostructures using various blended BCPs.

Clinical Implications of Basilar Artery Plaques in the Pontine Infarction with Normal Basilar Angiogram: A High-Resolution Magnetic Resonance Imaging Study.

BACKGROUND: Using high-resolution magnetic resonance imaging (HR-MRI), we investigated the impact of basilar artery plaques that were not detected by magnetic resonance angiography (MRA) on the functional outcomes of patients with acute pontine infarction. METHODS: A total of 40 patients with acute pontine infarction and normal basilar findings on MRA prospectively underwent HR-MRI for detection of basilar artery plaques. A relevant plaque was defined as one on the dorsal side of basilar artery, the same side of the ischemic lesion, and the same axial slices of the ischemic lesion. We analyzed the relationship between the relevant basilar artery plaques and the functional outcomes at 3 months. RESULTS: The initial National Institutes of Health Stroke Scale score (3.5 versus 2.0, P = .012), and the incidences of neurological deterioration (42.9% versus 6.3%, P = .031) and unfavorable functional outcome (71.4% versus 12.5%, P = .001) were higher in patients with relevant basilar artery plaques than in those without. On multiple regression analysis, the relevant basilar artery plaque was a significant and independent predictor of unfavorable functional outcome (odds ratio, 6.662; 95% confidence interval, 1.117-39.735; P = .037). CONCLUSIONS: The presence of a relevant basilar artery plaque was closely related with unfavorable functional outcome in patients with acute pontine infarction even if the patients' MRA showed normal basilar findings.

Lithium-Sulfur Capacitors.

Although many existing hybrid energy storage systems demonstrate promising electrochemical performances, imbalances between the energies and kinetics of the two electrodes must be resolved to allow their widespread commercialization. As such, the development of a new class of energy storage systems is a particular challenge, since future systems will require a single device to provide both a high gravimetric energy and a high power density. In this context, we herein report the design of novel lithium-sulfur capacitors. The resulting asymmetric systems exhibited energy densities of 23.9-236.4 Wh kg-1 and power densities of 72.2-4097.3 W kg-1, which are the highest reported values for an asymmetric system to date. This approach involved the use of a prelithiated anode and a hybrid cathode material exhibiting anion adsorption-desorption in addition to the electrochemical reduction and oxidation of sulfur at almost identical rates. This novel strategy yielded both high energy and power densities, and therefore establishes a new benchmark for hybrid systems.

Clinical predictors for favorable outcomes from endovascular recanalization in wake-up stroke.

BACKGROUND AND PURPOSE: Patients who have acute stroke symptoms present on awakening are ineligible for standard intravenous thrombolysis due to the unclear onset time of symptoms. Some of these wake-up stroke (WUS) patients may benefit from endovascular recanalization. This study aimed to evaluate clinical predictors of outcomes from endovascular recanalization in WUS patients. METHODS: Forty-one WUS patients with internal carotid (ICA) or middle cerebral artery (MCA) occlusion treated with endovascular recanalization were reviewed. Regression analysis was performed to measure clinical predictors of outcomes from endovascular recanalization in WUS patients. RESULTS: The mean initial NIHSS score was 16.41±4.96 (5-24). The mean symptom recognition-to-door time (SRDT) was 108.85±65.80 (19-230)min. Successful recanalization (TICI 2b-3) was achieved in 29 patients (70.7%). Thirty-four patients improved on NIHSS (amount 7.59±4.84, range; 1-17) at 7days after recanalization. At 90days after recanalization, a mRS of ≤2 was achieved in 19 patients (46.3%) and a mRS of ≤3 was achieved in 24 patients (58.5%). No symptomatic intracerebral hemorrhage occurred. Multivariate regression analysis identified SRDT (P=0.019), successful recanalization (P=0.005), and hypertension (P=0.013) were factors associated with an improvement of the NIHSS score. For a good functional outcome at 90days, SRDT (P=0.036) and initial NIHSS score (P=0.016) were found to be significant predictors. CONCLUSIONS: The results of this study suggest that the SRDT is an independent predictor of both an improvement of NIHSS score and a good functional outcome in endovascular recanalization for WUS patients.

Delicate Structural Control of Si-SiOx-C Composite via High-Speed Spray Pyrolysis for Li-Ion Battery Anodes.

Despite the high theoretical capacity, silicon (Si) anodes in lithium-ion batteries have difficulty in meeting the commercial standards in various aspects. In particular, the huge volume change of Si makes it very challenging to simultaneously achieve high initial Coulombic efficiency (ICE) and long-term cycle life. Herein, we report spray pyrolysis to prepare Si-SiOx composite using an aqueous precursor solution containing Si nanoparticles, citric acid, and sodium hydroxide (NaOH). In the precursor solution, Si nanoparticles are etched by NaOH with the production of [SiO4]4-. During the dynamic course of spray pyrolysis, [SiO4]4- transforms to SiOx matrix and citric acid decomposes to carbon surface layer with the assistance of NaOH that serves as a decomposition catalyst. As a result, a Si-SiOx composite, in which Si nanodomains are homogeneously embedded in the SiOx matrix with carbon surface layer, is generated by a one-pot process with a residence time of only 3.5 s in a flow reactor. The optimal composite structure in terms of Si domain size and Si-to-O ratio exhibited excellent electrochemical performance, such as reversible capacity of 1561.9 mAh g-1 at 0.06C rate and ICE of 80.2% and 87.9% capacity retention after 100 cycles at 1C rate.

Susceptibility-Weighted Imaging for Detection of Thrombus in Acute Cardioembolic Stroke.

BACKGROUND AND PURPOSE: Susceptibility-weighted imaging (SWI) can show an intravascular thrombus as a hypointense susceptibility vessel sign (SVS). In this study, we investigated the usefulness of SWI in the detection of an intravascular thrombus in acute cardioembolic stroke by comparing the SVS on SWI to the vessel status on time-of-flight magnetic resonance angiography (MRA). METHODS: We consecutively enrolled patients with cardioembolic stroke in the anterior circulation within 3 days from stroke onset. The frequency and location of the SVS on SWI were compared with those of occlusion on MRA. RESULTS: One hundred and twenty-two patients were conclusively enrolled in this study. The SVS was observed in 75.4% (92/122) of the enrolled patients. MRA showed occlusion in 57% (70/122) of the enrolled patients. The SVS was identified in all 70 patients with occlusion on MRA. The SVS was observed in 22 (42.3%) of 52 patients without occlusion on MRA (P<0.001), which was identified mainly in post-bifurcation segments of the middle cerebral artery: the M2 segment in 4 patients, M3 segment in 10 patients, M4 segment in 4 patients, A3 segment in 1 patient, and multiple segments in 2 patients. The mean length of the SVS in the M1 segment was 13.65 mm (median: 12.39 mm, length range: 2.70-39.50 mm). CONCLUSIONS: SWI can provide useful information about the thrombus location, the presence of a single thrombus or multiple thrombi especially in distal intracranial arteries, and the thrombus burden, all in acute cardioembolic stroke.

Thyroid Autoantibody Positive Anti-N-Methyl-D-Aspartate Receptor Encephalitis.

BACKGROUND: Hashimoto's encephalopathy (HE) and anti N-methyl-D-aspartate receptor (NMDAR) encephalitis have clinical overlaps. CASE REPORT: A 70-year-old woman presented with acutely developed confusion, disorientations and psychosis. HE was suspected based on goiter, markedly elevated anti-thyroglobulin and anti-thyroid peroxidase antibody. She was placed on high dose steroid and intravenous immunoglobulins administration, which did not ameliorate her symptoms. After the antibodies to the NMDAR were identified, weekly 500 mg of rituximab with 4 cycles were started. The current followed up indicated a complete recovery. CONCLUSIONS: The possible associations between NMDAR antibody and autoimmune thyroid antibodies in anti-NMDAR encephalitis with positive thyroid autoantibodies remain unclear. However, a trend toward a higher incidence of NMDAR antibody in patients with autoimmune thyroid antibodies than without has been observed. Cases of encephalitis with only NMDAR antibody (pure anti-NMDAR encephalitis) also occur. Therefore, it is important for clinicians to know the clinical and pathogenic differences between anti-NMDAR encephalitis with positive thyroid autoantibody and pure anti-NMDAR encephalitis for relevant treatment, predicting prognosis, and future follow-up.

Anti-NMDA Receptor Encephalitis in a Pregnant Woman.

Anti N-methyl-D-aspartate (NMDA) receptor encephalitis is one of the most common types of autoimmune synaptic encephalitis. Anti-NMDA receptor encephalitis commonly occurs in young women with ovarian teratoma. It has variable clinical manifestations and treatment responses. Sometimes it is misdiagnosed as a psychiatric disorder or viral encephalitis. To the best of our knowledge, anti-NMDA receptor encephalitis is a rare condition in pregnant women. We report a case of anti-NMDA receptor encephalitis in a pregnant woman who presented with abnormal behavior, epileptic seizure, and hypoventilation.

Can an exercise bicycle be safely used in the epilepsy monitoring unit?: An exercise method to provoke epileptic seizures and the related safety issues.

BACKGROUND AND PURPOSE: Long-term videoelectroencephalogram (video-EEG) monitoring is performed to diagnose an epileptic seizure and to investigate the differential diagnosis of paroxysmal events. To provoke an epileptic seizure, an exercise method is performed in some cases during long-term video-EEG recording in the epilepsy monitoring unit (EMU). The purpose of this study was two-fold: to assess the frequency and severity of adverse events associated with the use of an exercise bicycle and to find a way to safely use it in the EMU. METHODS: A retrospective survey was performed on all epileptic seizure videos recorded in the EMU from January 2012 to December 2013. Three hundred and fifty patients were included in this study. RESULTS: Eleven patients experienced an epileptic seizure while riding the exercise bicycle in the EMU. One patient's foot got stuck between the cycling pedal and its strap, and one patient fell off the exercise bicycle during the epileptic seizure. However, there were no serious adverse events over two years. CONCLUSION: Epileptic seizures were not frequent while riding the exercise bicycle, and serious injuries did not occur. But, there is a need to improve the safety in the EMU to control the potentially dangerous factors associated with the use of the exercise bicycle and to continuously monitor the patients with help from the staff.

A half millimeter thick coplanar flexible battery with wireless recharging capability.

Most of the existing flexible lithium ion batteries (LIBs) adopt the conventional cofacial cell configuration where anode, separator, and cathode are sequentially stacked and so have difficulty in the integration with emerging thin LIB applications, such as smart cards and medical patches. In order to overcome this shortcoming, herein, we report a coplanar cell structure in which anodes and cathodes are interdigitatedly positioned on the same plane. The coplanar electrode design brings advantages of enhanced bending tolerance and capability of increasing the cell voltage by in series-connection of multiple single-cells in addition to its suitability for the thickness reduction. On the basis of these structural benefits, we develop a coplanar flexible LIB that delivers 7.4 V with an entire cell thickness below 0.5 mm while preserving stable electrochemical performance throughout 5000 (un)bending cycles (bending radius = 5 mm). Also, even the pouch case serves as barriers between anodes and cathodes to prevent Li dendrite growth and short-circuit formation while saving the thickness. Furthermore, for convenient practical use wireless charging via inductive electromagnetic energy transfer and solar cell integration is demonstrated.

Functional outcome after recanalization for acute pure M1 occlusion of the middle cerebral artery as assessed by collateral CTA flow.

OBJECTIVE: Collateral flow is important for ischemic brain tissue after an acute occlusion of the cerebral artery. The purpose of this study was to evaluate baseline collateral flow, on CT angiography (CTA), as a predictor of functional outcome in patients who had endovascular recanalization, after acute pure first segment (M1) occlusion of the middle cerebral artery (MCA). METHODS: Thirty patients with acute pure M1 occlusion treated by endovascular recanalization, who were ineligible for intravenous thrombolysis or resistant to intravenous thrombolysis, were reviewed. The relationship between baseline collateral flow, on CTA, and functional outcome, was analyzed. In addition, other factors affecting clinical outcome were assessed. RESULTS: The mean NIHSS score on admission was 16.87±4.86 (7-24). The mean time interval between onset of stroke symptoms and recanalization was 324.37±68.38 (210-463) min. Successful recanalization (TICI 2b-3) was achieved in 18 patients (60%). Twenty-seven of 30 patients improved their NIHSS score (mean 8.4); NIHSS score 8.9±5.4 (median 10, range 0-16) at seven days. Two patients had aggravated symptoms and one patient had no change on the NIHSS score. At 90 days after recanalization, a modified Rankin Scale (mRS) of ≤3 was achieved in 15 patients (50%) and a mRS of ≤2 was achieved in nine patients (30%). Symptomatic intra-cerebral hemorrhage occurred in two patients (6.7%). Multivariate regression analysis showed an initial NIHSS score (p=0.004), grade of baseline collateral flow on CTA (p=0.025), presence of diabetes mellitus (p=0.037), and TICI scale (p=0.049) were factors associated with an improved NIHSS. For the mRS at 90 days, only the grade of the baseline collateral flow on CTA was associated with a good functional outcome (p=0.013). CONCLUSIONS: The results of this study suggest that the grade of baseline collateral flow, on CTA, is an independent predictor of functional outcome for endovascular recanalization of acute pure M1 occlusion of the middle cerebral artery.