Relapsing TIPIC Syndrome after Administration of an mRNA-Based COVID-19 Vaccine.

Reported vascular complications following mRNA-based COVID-19 vaccines are consisting of myocarditis, cerebral venous thrombosis, cerebral vascular thrombosis, and vaccine-induced thrombocytopenia. Here, we describe a case of a 49-year-old woman with left-sided pain above the middle common carotid artery (carotidynia) starting a few days after her second vaccination with an mRNA-based COVID-19 vaccine (Spikevax). Imaging was indicative of transient perivascular inflammation of the carotid artery (TIPIC) syndrome. The diagnostic workup for other immunologically mediated diseases was negative. The inflammation subsided after a course of prednisone and aspirin, and clinical symptoms vanished, but later mildly relapsed in the context of a viral upper respiratory tract infection other than SARS-CoV-2. Carotidynia because of TIPIC syndrome may present as an immunogenic side effect of the newly developed mRNA-based vaccinations against COVID-19. TIPIC syndrome should be considered in new-onset neck pain after vaccination.

Prognostic Factors in COVID-19 Patients With New Neurological Manifestations: A Retrospective Cohort Study in a Romanian Neurology Department.

Introduction: The emerging Coronavirus Disease (COVID-19) pandemic caused by Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a serious public health issue due to its rapid spreading, high mortality rate and lack of specific treatment. Given its unpredictable clinical course, risk assessment, and stratification for severity of COVID-19 are required. Apart from serving as admission criteria, prognostic factors might guide future therapeutic strategies. Aim: We aimed to compare clinical features and biological parameters between elderly (age ≥ 65 years) and non-elderly (age <65 years) patients with COVID-19 and new neurological symptoms/conditions. We also aimed to determine factors independently associated with all-cause in-hospital mortality. Methods: All consecutive patients with COVID-19 and new neurological symptoms/conditions admitted in our Neurology Department between April 1 and August 23, 2020 were enrolled in this observational retrospective cohort study. Patient characteristics such as demographic data, comorbidities, biological parameters, imaging findings and clinical course were recorded. All-cause in-hospital mortality was the main outcome, whereas COVID-19 severity, hospitalization duration and the levels of supplemental oxygen were the secondary outcomes. Results: One hundred forty-eight patients were included, out of which 54.1% were women. The average age was 59.84 ± 19.06 years and 47.3% were elderly, the majority having cardiovascular and metabolic comorbidities. In the elderly group, the most frequent neurological symptoms/manifestations responsible for hospitalization were stroke symptoms followed by confusion, whereas in the non-elderly, headache prevailed. The final neurological diagnosis significantly varied between the two groups, with acute cerebrovascular events and acute confusional state in dementia most commonly encountered in the elderly (65.71 and 14.28%, respectively) and secondary headache attributed to SARS-CoV-2 infection often experienced by the non-elderly (38.46%). The elderly had statistically significant higher median values of white blood cell (8,060 vs. 6,090/µL) and neutrophil count (6,060 vs. 4,125/µL), C-reactive protein (29.2 vs. 5.72 mg/L), ferritin (482 vs. 187 mg/dL), fibrinogen (477 vs. 374 mg/dL), D-dimer (1.16 vs. 0.42), prothrombin time (151.15 vs. 13.8/s), aspartate transaminase (26.8 vs. 20.8 U/l), creatinine (0.96 vs. 0.77 mg/dL), and blood urea nitrogen level (51.1 vs. 27.65 mg/dL), as well as lower median value of hemoglobin (13.05 vs. 13.9 g/dL) and lymphocyte count (1,245 vs. 1,670/µL). Moreover, advanced age was significantly associated with more extensive lung involvement (25 vs. 10%) and higher fatality rate (40 vs. 9%). Overall, the mortality rate was 23.6%. Age as well as neutrophil count, C-reactive protein, fibrinogen, and activated partial thromboplastin time levels were independently associated with mortality. Conclusions: Older age, higher neutrophil count, C-reactive protein, fibrinogen, and activated partial thromboplastin time levels are independent predictors of mortality in COVID-19 patients with new neurological manifestations/conditions at admission.

Plasmon-Driven Electrochemical Methanol Oxidation on Gold Nanohole Electrodes.

Direct methanol oxidation is expected to play a central role in low-polluting future power sources. However, the sluggish and complex electro-oxidation of methanol is one of the limiting factors for any practical application. To solve this issue, the use of plasmonic is considered as a promising way to accelerate the methanol oxidation reaction. In this study, we report on a novel approach for achieving enhanced methanol oxidation currents. Perforated gold thin film anodes were decorated with Pt/Ru via electrochemical deposition and investigated for their ability for plasmon-enhanced electrocatalytic methanol oxidation in alkaline media. The novel methanol oxidation anode (AuNHs/PtRu), combining the strong light absorption properties of a gold nanoholes array-based electrode (AuNHs) with surface-anchored bimetallic Pt/Ru nanostructures, known for their high activity toward methanol oxidation, proved to be highly efficient in converting methanol via the hot holes generated in the plasmonic electrode. Without light illumination, AuNHs/PtRu displayed a maximal current density of 13.7 mA/cm2 at -0.11 V vs Ag/AgCl. Enhancement to 17.2 mA/cm2 was achieved under 980 nm laser light illumination at a power density of 2 W/cm2. The thermal effect was negligible in this system, underlining a dominant plasmon process. Fast generation and injection of charge carriers were also evidenced by the abrupt change in the current density upon laser irradiation. The good stability of the interface over several cycles makes this system interesting for methanol electro-oxidation.

Kinked Silicon Nanowires: Superstructures by Metal-Assisted Chemical Etching.

We report on metal-assisted chemical etching of Si for the synthesis of mechanically stable, hybrid crystallographic orientation Si superstructures with high aspect ratio, above 200. This method sustains high etching rates and facilitates reproducible results. The protocol enables the control of the number, angle, and location of the kinks via successive etch-quench sequences. We analyzed relevant Au mask catalyst features to systematically assess their impact on a wide spectrum of etched morphologies that can be easily attained and customized by fine-tuning of the critical etching parameters. For instance, the designed kinked Si nanowires can be incorporated in biological cells without affecting their viability. An accessible numerical model is provided to explain the etch profiles and the physicochemical events at the Si/Au-electrolyte interface and offers guidelines for the development of finite-element modeling of metal-assisted Si chemical etching.

Kinked silicon nanowires-enabled interweaving electrode configuration for lithium-ion batteries.

A tri-dimensional interweaving kinked silicon nanowires (k-SiNWs) assembly, with a Ni current collector co-integrated, is evaluated as electrode configuration for lithium ion batteries. The large-scale fabrication of k-SiNWs is based on a procedure for continuous metal assisted chemical etching of Si, supported by a chemical peeling step that enables the reuse of the Si substrate. The kinks are triggered by a simple, repetitive etch-quench sequence in a HF and H2O2-based etchant. We find that the inter-locking frameworks of k-SiNWs and multi-walled carbon nanotubes exhibit beneficial mechanical properties with a foam-like behavior amplified by the kinks and a suitable porosity for a minimal electrode deformation upon Li insertion. In addition, ionic liquid electrolyte systems associated with the integrated Ni current collector repress the detrimental effects related to the Si-Li alloying reaction, enabling high cycling stability with 80% capacity retention (1695 mAh/gSi) after 100 cycles. Areal capacities of 2.42 mAh/cm2 (1276 mAh/gelectrode) can be achieved at the maximum evaluated thickness (corresponding to 1.3 mgSi/cm2). This work emphasizes the versatility of the metal assisted chemical etching for the synthesis of advanced Si nanostructures for high performance lithium ion battery electrodes.

Mechanochemical Synthesis of PEDOT:PSS Hydrogels for Aqueous Formulation of Li-Ion Battery Electrodes.

Water-soluble binders can enable greener and cost-effective Li-ion battery manufacturing by eliminating the standard fluorine-based formulations and associated organic solvents. The issue with water-based dispersions, however, remains the difficulty in stabilizing them, requiring additional processing complexity. Herein, we show that mechanochemical conversion of a regular poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) water-based dispersion produces a hydrogel that meets all the requirements as binder for lithium-ion battery electrode manufacture. We particularly highlight the suitable slurry rheology, improved adhesion, intrinsic electrical conductivity, large potential stability window and limited corrosion of metal current collectors and active electrode materials, compared to standard binder or regular PEDOT:PSS solution-based processing. When incorporating the active materials, conductive carbon and additives with PEDOT:PSS, the mechanochemical processing induces simultaneous binder gelation and fine mixing of the components. The formed slurries are stable, show no phase segregation when stored for months, and produce highly uniform thin (25 µm) to very thick (500 µm) films in a single coating step, with no material segregation even upon slow drying. In conjunction with PEDOT:PSS hydrogels, technologically relevant materials including silicon, tin, and graphite negative electrodes as well as LiCoO2, LiMn2O4, LiFePO4, and carbon-sulfur positive electrodes show superior cycling stability and power-rate performances compared to standard binder formulation, while significantly simplifying the aqueous-based electrode assembly.

Surface coating mediated swelling and fracture of silicon nanowires during lithiation.

Surface passivation of silicon anodes is an appealing design strategy for the development of reliable, high-capacity lithium-ion batteries. However, the structural stability of the coating layer and its influence on the lithiation process remain largely unclear. Herein, we show that surface coating mediates the swelling dynamics and the fracture pattern during initial lithiation of crystalline silicon nanopillars. We choose conformally nickel coated silicon architectures as a model system. Experimental findings are interpreted based on a chemomechanical model. Markedly different swelling and fracture regimes have been identified, depending on the coating thickness and silicon nanopillar diameter. Nanopillars with relatively thin coating display anisotropic swelling similar to pristine nanopillars, but with different preferred fracture sites. As the coating thickness increases, the mechanisms become isotropic, with one randomly oriented longitudinal crack that unzips the core-shell structure. The morphology of cracked pillars resembles that of a thin-film electrode on a substrate, which is more amenable to cyclic lithiation without fracture. The knowledge provided here helps clarify the cycling results of coated nanosilicon electrodes and further suggests design rules for better performance electrodes through proper control of the lithiation and fracture.