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Chang Zhou, Lei Zhang, Xuemei Jiang, Shanshan Shi, Qiuhong Yu, Qihui Chen, Dan Yao, Yonghui Pan Department of Neurology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, 150000, People’s Republic of ChinaCorrespondence: Yonghui PanDepartment of Neurology, The First Affiliated Hospital of Harbin Medical University, No. 199 Dazhi Street, Nangang District, Harbin City, Heilongjiang 150000, People’s Republic of ChinaTel +86 13945693065Email aigui1993@126.comBackground: Increasing morbidity and misdiagnosis of vestibular migraine (VM) gravely affect the treatment of the disease as well as the patients’ quality of life. A powerful diagnostic prediction model is of great importance for management of the disease in the clinical setting.Materials and Methods: Patients with a main complaint of dizziness were invited to join this prospective study. The diagnosis of VM was made according to the International Classification of Headache Disorders. Study variables were collected from a rigorous questionnaire survey, clinical evaluation, and laboratory tests for the development of a novel predictive diagnosis model for VM.Results: A total of 235 patients were included in this study: 73 were diagnosed with VM and 162 were diagnosed with non-VM vertigo. Compared with non-VM vertigo patients, serum magnesium levels in VM patients were lower. Following the logistic regression analysis of risk factors, a predictive model was developed based on 6 variables: age, sex, autonomic symptoms, hypertension, cognitive impairment, and serum Mg2+ concentration. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve was 0.856, which was better than some of the reported predictive models.Conclusion: With high sensitivity and specificity, the proposed logistic model has a very good predictive capability for the diagnosis of VM. It can be used as a screening tool as well as a complementary diagnostic t

The low loading and poor cycling performance of sulfur cathodes are among the critical barriers restricting the practical application of lithium–sulfur (Li–S) batteries. The rational design of composites consisting of transition metals and conductive nanocarbon is considered an effective strategy to construct cathode materials for Li–S batteries with excellent cycling stability and rate capability. Herein, we propose a spray drying method to fabricate 3D pomegranate-like titanium nitride (TiN)@graphene composites as hosts for sulfur cathodes. The hollow spheres are coated with graphene layers to form a shell, serving as a highly efficient electrochemical reaction chamber and a reservoir for polysulfides. The TiN@graphene/S electrode exhibits an excellent capacity of 810 mA h g−1 after 200 cycles at 0.5C. The cathodes with high areal sulfur loadings of 2.8 and 3.6 mg cm−2 maintained remarkable capacities of 568 and 515 mA h g−1, respectively, after 500 cycles. The TiN hollow spheres not only accommodate the large volume expansion of sulfur but also improve the conversion of polysulfides during the discharge/charge process. The excellent electrical conductivity of the few-layered graphene shell facilitates electron transport and maintains structural stability. This work offers a strategy to combine inorganic compounds and nanocarbon as sulfur hosts to improve the electrochemical properties of Li–S batteries.

Lithium-sulfur (Li-S) batteries are promising energy storage systems due to their large theoretical energy density of 2600 Wh kg(-1) and cost effectiveness. However, the severe shuttle effect of soluble lithium polysulfide intermediates (LiPSs) and sluggish redox kinetics during the cycling process cause low sulfur utilization, rapid capacity fading, and a low coulombic efficiency. Here, a 3D copper, nitrogen co-doped hierarchically porous graphitic carbon network developed through a freeze-drying method (denoted as 3D Cu@NC-F) is prepared, and it possesses strong chemical absorption and electrocatalytic conversion activity for LiPSs as highly efficient sulfur host materials in Li-S batteries. The porous carbon network consisting of 2D cross-linked ultrathin carbon nanosheets provides void space to accommodate volumetric expansion upon lithiation, while the Cu, N-doping effect plays a critical role for the confinement of polysulfides through chemical bonding. In addition, after sulfuration of Cu@NC-F network, the in situ grown copper sulfide (CuxS) embedded within CuxS@NC/S-F composite catalyzes LiPSs conversion during reversible cycling, resulting in low polarization and fast redox reaction kinetics. At a current density of 0.1 C, the CuxS@NC/S-F composites' electrode exhibits an initial capacity of 1432 mAh g(-1) and maintains 1169 mAh g(-1) after 120 cycles, with a coulombic efficiency of nearly 100%.

Due to the high specific capacities and environmental benignity, lithium-sulfur (Li-S) batteries have shown fascinating potential to replace the currently dominant Li-ion batteries to power portable electronics and electric vehicles. However, the shuttling effect caused by the dissolution of polysulfides seriously degrades their electrochemical performance. In this paper, Mn2O3 microcubes are fabricated to serve as the sulfur host, on top of which Al2O3 layers of 2 nm in thickness are deposited via atomic layer deposition (ALD) to form Mn2O3/S (MOS) @Al2O3 composite electrodes. The MOS@Al2O3 electrode delivers an excellent initial capacity of 1012.1 mAh g−1 and a capacity retention of 78.6% after 200 cycles at 0.5 C, and its coulombic efficiency reaches nearly 99%, giving rise to much better performance than the neat MOS electrode. These findings demonstrate the double confinement effect of the composite electrode in that both the porous Mn2O3 structure and the atomic Al2O3 layer serve as the spacious host and the protection layer of sulfur active materials, respectively, for significantly improved electrochemical performance of the Li-S battery.

The holothurian-like γ-MnS/carbon nanotube (CNT) nanocomposites are successfully fabricated through a facile two-step hydrothermal method. The γ-MnS@CNT hybrid nanocomposite is an attractive electrode material for supercapacitors as it exhibits excellent electrochemical performance with a high specific capacitance of 641.9 F g−1 and cyclic stability of 94.6 % retention after 3000 cycles at a current density of 0.5 A g−1, which are superior to those of CNTs and pure γ-MnS nanoparticles. Furthermore, the as-fabricated all-solid-state supercapacitor reveals remarkable specific capacitance of 263.5 F g−1, high capacitance retention, and a high energy density of 36.6 Wh kg−1 at a power density of 0.5 kW kg−1. The device maintains its supercapacitor performance well, even under bending or twisting states, indicating the excellent mechanical stability and flexibility of the device. The impressive results demonstrate the great opportunity for practical application of this metal sulfide-based composite in high-performance, flexible energy storage devices and wearable electronics.

A promising hybrid material composed of tubular polypyrrole (T-PPy)-wrapped monodisperse biomass-derived carbon nanospheres (BCSs) was first synthesized successfully via a simple hydrothermal approach by using watermelon juice as the carbon source, and further used as an anchoring object for sulfur (S) of lithium–sulfur (Li–S) batteries. The use of BCSs with hydrophilic nature as a framework could provide large interface areas between the active materials and electrolyte, and improve the dispersion of T-PPy, which could help in the active material utilization. As a result, BCS@T-PPy/S as a cathode material exhibited a high capacity of 1143.6 mA h g−1 and delivered a stable capacity up to 685.8 mA h g−1 after 500 cycles at 0.5 C, demonstrating its promising application for rechargeable Li–S batteries.