A Functional Janus Ag Nanowires/Bacterial Cellulose Separator for High-Performance Dendrite-Free Zinc Anode Under Harsh Conditions.

Aqueous zinc-ion batteries (AZIBs) offer promising prospects for large-scale energy storage due to their inherent abundance and safety features. However, the growth of zinc dendrites remains a primary obstacle to the practical industrialization of AZIBs, especially under harsh conditions of high current densities and elevated temperatures. To address this issue, a Janus separator with an exceptionally ultrathin thickness of 29 µm is developed. This Janus separator features the bacterial cellulose (BC) layer on one side and Ag nanowires/bacterial cellulose (AgNWs/BC) layer on the other side. High zincophilic property and excellent electric/thermal conductivity of AgNWs make them ideal for serving as an ion pump to accelerate Zn2+ transport in the electrolyte, resulting in greatly improved Zn2+ conductivity, deposition of homogeneous Zn nuclei, and dendrite-free Zn. Consequently, the Zn||Zn symmetrical cells with the Janus separator exhibit a stable cycle life of over 1000 h under 80 mA cm-2 and are sustained for over 600 h at 10 mA cm-2 under 50 °C. Further, the Janus separator enables excellent cycling stability in AZIBs, aqueous zinc-ion capacitors (AZICs), and scaled-up flexible soft-packaged batteries. This study demonstrates the potential of functional separators in promoting the application of aqueous zinc batteries, particularly under harsh conditions.

Monodispersed MOF-Modified Nanofibers as Versatile Building Blocks for the Ion Regulations in Safe Lithium-Sulfur Batteries.

Lithium-sulfur battery is the most promising candidate for the next generation of rechargeable batteries because of the high energy density. However, the severe shuttle effect of lithium polysulfides (LiPSs) and degradation of the lithium anode during cycling are significant issues that hinder the practical application of lithium-sulfur batteries. Herein, monodispersed metal-organic framework (MOF)-modified nanofibers are prepared as building blocks to construct both a separator and a composite polymer electrolyte in lithium-sulfur systems. This building block possesses the intrinsic advantages of good mechanical properties, thermal stability, and good electrolyte affinity. MOFs, grown continuously on the monodispersed nanofibers, can effectively adsorb LiPSs and play a key role in regulating the nucleation and stripping/plating process of the lithium anode. When assembled into the separator, the symmetric battery remains stable for 2500 h at a current density of 1 mA cm-2, and the lithium-sulfur full cell shows improved electrochemical performance. In order to improve the safety property, the composite polymer electrolyte is prepared with the MOF-modified nanofiber as the filler. The quasi-solid-state symmetric battery remains stable for 3000 h at a current density of 0.1 mA cm-2, and the corresponding lithium-sulfur cell can cycle 800 times at 1 C with a capacity decay rate of only 0.038% per cycle.

Estimated Annual Economic Burden of Dry Eye Disease Based on a Multi-Center Analysis in China: A Retrospective Study.

Purpose: To conduct a multi-center analysis and assess the economic burden due to dry eye disease (DED) in China. Design: A retrospective and cross-sectional study. Methods: Patients (n = 598) with diagnosed DED were recruited from 3 eye centers (in central, southeast, and northeast China) from 1 January 2018 to 31 December 2018. Data were collected regarding the examination, pharmacological therapy, and non-pharmacological therapy fees. Sub-group analyses were stratified by eye center, DED severity, types of DED, number of visits to physicians, and residential area. A logistic regression analysis was conducted to investigate the variables influencing total costs. Results: The per capita costs devoted to DED at the 3 centers were 422.6, 391.3, and 265.4 USD, respectively. The costs of non-pharmacological therapy accounted the largest part in three centers (75.6, 76.4, 76.5%, respectively). Patients with severe DED sustained the largest economic burden. Patients with mixed type of DED spent the most comparing to patients with either evaporative or aqueous-deficient types of DED. Patients spent more during the first visit compared with subsequent visits. Patients living in urban areas spent significantly more than did those living in rural areas (P = 0.001). The logistics regression analysis showed that total costs were significantly influenced by DED severity, number of visits to physicians, and area of residence (beta = 2.83, 0.83, 1.48; P < 0.0001). Conclusions: DED is a chronic ocular disease that timely non-cost counseling, early diagnosis, and efficacious treatment can reduce its economic burden on patients and the society.

Annual direct economic burden and influencing factors of dry eye disease in Central China.

PURPOSE: To study the direct economic burden of dry eye diseases (DED) on Chinese residents and analyze the influencing factors of the direct economic burden of patients with DED. METHODS: Two hundred and twenty-one Chinese adults with DED who underwent treatment in Wuhan Aier Hankou Eye Hospital were enrolled in this health economics research from January 2018 to August 2018 and followed for at least 1 year. Examination, pharmacological therapy, and nonpharmacological therapy costs were collected to calculate the annual direct economic burden of DED on patients through the outpatient medical record system. RESULTS: Annual direct economic burden caused by DED on each patient was $465.54 ± 303.08. The direct economic burden of female patients in the 40-49 years group was significantly higher than that of male patients (P < .05). Age, number of hospital visits and severity of DED were showed a significant influence on the direct economic burden both in univariate linear regression analysis and multiple linear regression analysis. Subtype of DED was showed a significant influence on the direct economic burden in multiple linear regression analysis after eliminating confounding factors. CONCLUSION: This study preliminarily analyzed the direct economic burden of Chinese DED patients. Age, number of hospital visits, severity of DED, mixed and evaporative dry eye (EDE) subtypes are shown to be the significant influencing factors of the direct economic burden and sex is a potential influencing factor.

Electrochemical Generation of Hydrated Zinc Vanadium Oxide with Boosted Intercalation Pseudocapacitive Storage for a High-Rate Flexible Zinc-Ion Battery.

With the surging development of flexible wearable and stretchable electronic devices, flexible energy-storage devices with excellent electrochemical properties are in great demand. Herein, a flexible Zn-ion battery comprised by hydrated zinc vanadium oxide/carbon cloth (ZnVOH/CC) as the cathode is developed, and it shows a high energy density, superior lifespan, and good safety. ZnVOH/CC is obtained by the in situ transformation of hydrated vanadium oxide/carbon cloth (VOH/CC) by an electrochemical method, and the intercalation pseudocapacitive reaction mechanism is discovered for ZnVOH/CC. The co-insertion/deinsertion of H+/Zn2+ is observed; the H+ insertion dominates in the initial discharge stage and the high-rate electrochemical process, while Zn2+ insertion dominates the following discharge stage and the low-rate electrochemical procedure. An ultrastable reversible capacity of 135 mAh g-1 at 20 A g-1 is obtained after 5000 cycles without capacity fading. Moreover, the as-assembled flexible zinc-ion battery can operate normally under rolled, folded, and punched conditions with superior safety. It is capable to deliver a high discharge capacity of 184 mAh g-1 at 10 A g-1 after 170 cycles. This work paves a new way for designing low-cost, safe, and quick-charging energy-storage devices for flexible electronics.

Effects of chalazion and its treatments on the meibomian glands: a nonrandomized, prospective observation clinical study.

BACKGROUND: To observe the effects of chalazion and its treatments on meibomian gland function and morphology in the chalazion area. METHODS: This nonrandomized, prospective observational clinical study included 58 patients (67 eyelids) who were cured of chalazion, including 23 patients (23 eyelids) treated with a conservative method and 35 patients (44 eyelids) treated with surgery. Infrared meibomian gland photography combined with image analysis by ImageJ software was used to measure the chalazion area proportion. Slit-lamp microscopy was employed to evaluate meibomian gland function, and a confocal microscope was used to observe meibomian gland acinar morphology before treatment and 1 month after complete chalazion resolution. RESULTS: At 1 month after chalazion resolution, the original chalazion area showed meibomian gland loss according to infrared meibomian gland photography in both groups. In patients who received conservative treatment, the meibomian gland function parameters before treatment were 0.74 ± 0.75, 0.48 ± 0.67, and 1.22 ± 0.60, respectively. One month after chalazion resolution, the parameters were 0.35 ± 0.49, 0.17 ± 0.49, and 0.91 ± 0.60, respectively; there was significant difference (P < 0.05). The proportion of the chalazion area before treatment was 14.90 (11.03, 25.3), and the proportion of meibomian gland loss at 1 month after chalazion resolution was 14.64 (10.33, 25.77); there was no significant difference (P > 0.05). In patients who underwent surgery, the meibomian gland function parameters before surgery were 0.93 ± 0.87, 1.07 ± 0.70, and 1.59 ± 0.76, respectively, and at 1 month after chalazion resolution, they were 0.93 ± 0.82, 0.95 ± 0.75, and 1.52 ± 0.70, respectively; there was no significant difference (P > 0.05). The proportion of the chalazion area before surgery was 14.90 (12.04, 21.6), and the proportion of meibomian gland loss at 1 month after chalazion resolution was 14.84 (11.31, 21.81); there was no significant difference (P > 0.05). The acinar structure could not be observed clearly in the meibomian gland loss area in most patients. CONCLUSIONS: Chalazion causes meibomian gland loss, and the range of meibomian gland loss is not related to the treatment method but to the range of chalazion itself. A hot compress as part of conservative treatment can improve meibomian gland function at the site of chalazion in the short term.

Effects of Botulinum Toxin Type A on Microvessels in Hypertrophic Scar Models on Rabbit Ears.

BACKGROUND: Although Botulinum Toxin Type A (BTXA) has been applied to scar prevention and treatment, the mechanisms still require further exploration. OBJECTIVE: To investigate the effects of BTXA on microvessels in the hypertrophic scar models on rabbit ears. METHODS: Eight big-eared New Zealand rabbits (males or females) were selected to establish scar models. One ear of each rabbit (4 models in each ear) was selected randomly to be injected with BTXA immediately after modeling and included in the treated group, while the opposite ear was untreated and included in the control group. The growth of scars in each group was observed and recorded, and 4 rabbits were sacrificed on days 30 and 45 after modeling. Then, scar height was measured by hematoxylin-eosin (HE) staining, vascular endothelial growth factor (VEGF) expression was detected by immunohistochemical (IHC) testing, and microvessel density (MVD) was calculated based on CD34 (human hematopoietic progenitor cell antigen). RESULTS: The wounds in each group were well healed and free from infection or necrosis. On days 30 and 45, the scar height, MVD value, and VEGF expression in the treated group were lower than those in the control group (P < 0.05). For the treated group, the above indicators on day 45 were lower than on day 30 (P > 0.05). Besides, there was a positive correlation between the MVD value and the VEGF expression in the treated group (P < 0.05). CONCLUSION: The injection of BTXA immediately after modeling inhibits VEGF expression and reduces angiogenesis, thereby inhibiting hypertrophic scar formation.

The rational design of carbon coated Fe2(MoO4)3 nanosheets for lithium-ion storage with high initial coulombic efficiency and long cycle life.

Binary metal oxides are potential anode materials for lithium-ion storage due to their high theoretical specific capacities. However, the practical applications of metal oxides are limited due to their large volume changes and sluggish reaction kinetics. Herein, carbon coated Fe2(MoO4)3 nanosheets are prepared via a simple method, adopting urea as the template and carbon source. The carbon coating on the surface helps to elevate the conductivity of the active material and maintain structural integrity during the lithium storage process. Combining this with a catalytic effect from the generated Fe, leading to the reversible formation of a solid electrolyte interface layer, a high initial coulombic efficiency (>87%) can be obtained. Based on this, the carbon coated Fe2(MoO4)3 nanosheets show excellent rate capability (a reversible discharge capacity of 983 mA h g-1 at 5 A g-1) and stable cycling performance (1376 mA h g-1 after 250 cycles at 0.5 A g-1 and 864 mA h g-1 after 500 cycles at 2 A g-1). This simple in situ carbonization and template method using urea provides a facile way to optimize electrode materials for next-generation energy storage devices.

Self-templated construction of 1D NiMo nanowires via a Li electrochemical tuning method for the hydrogen evolution reaction.

NiMo based materials have been widely recognized as the most promising alternatives to noble Pt electrocatalysts used in alkaline electrolytes for the hydrogen evolution reaction. However, it is difficult to construct a nanostructure, especially 1D morphology, for NiMo materials via an electrochemical method. Herein, a novel Li electrochemical tuning method, for the first time, is introduced to synthesize 1D NiMo nanowires by insertion of lithium ions into parent NiMoO4 nanorods. The as-prepared NiMo catalyst exhibits high HER activity in 1 M KOH, in terms of low overpotential (73 mV) at a current density of 10 mA cm-2 and a small Tafel slope (37.2 mV dec-1) and charge transfer resistance (11.3 Ω). Furthermore, no decay in catalytic performance is observed for this material when it is operated at -0.125 V (vs. RHE) for 1250 min and a high Faraday efficiency (96%) is achieved. The high activity of NiMo is ascribed to the synergistic interplay between Ni and Mo and its unique nanostructure, which can expose more active sites and facilitate the mass transfer and hydrogen bubble release.

Fe2 VO4 Hierarchical Porous Microparticles Prepared via a Facile Surface Solvation Treatment for High-Performance Lithium and Sodium Storage.

Preventing the aggregation of nanosized electrode materials is a key point to fully utilize the advantage of the high capacity. In this work, a facile and low-cost surface solvation treatment is developed to synthesize Fe2 VO4 hierarchical porous microparticles, which efficiently prevents the aggregation of the Fe2 VO4 primary nanoparticles. The reaction between alcohol molecules and surface hydroxy groups is confirmed by density functional theory calculations and Fourier transform infrared spectroscopy. The electrochemical mechanism of Fe2 VO4 as lithium-ion battery anode is characterized by in situ X-ray diffraction for the first time. This electrode material is capable of delivering a high reversible discharge capacity of 799 mA h g-1 at 0.5 A g-1 with a high initial coulombic efficiency of 79%, and the capacity retention is 78% after 500 cycles. Moreover, a remarkable reversible discharge capacity of 679 mA h g-1 is achieved at 5 A g-1 . Furthermore, when tested as sodium-ion battery anode, a high reversible capacity of 382 mA h g-1 can be delivered at the current density of 1 A g-1 , which still retains at 229 mA h g-1 after 1000 cycles. The superior electrochemical performance makes it a potential anode material for high-rate and long-life lithium/sodium-ion batteries.

Micrometer-Sized Porous Fe2 N/C Bulk for High-Areal-Capacity and Stable Lithium Storage.

High-capacity anodes of lithium-ion batteries generally suffer from poor electrical conductivity, large volume variation, and low tap density caused by prepared nanostructures, which make it an obstacle to achieve both high-areal capacity and stable cycling performance for practical applications. Herein, micrometer-sized porous Fe2 N/C bulk is prepared to tackle the aforementioned issues, and thus realize both high-areal capacity and stable cycling performance at high mass loading. The porous structure in Fe2 N/C bulk is beneficial to alleviate the volumetric change. In addition, the N-doped carbon conducting networks with high electrical conductivity provide a fast charge transfer pathway. Meanwhile, the micrometer-sized Fe2 N/C bulk exhibits a higher tap density than that of commercial graphite powder (1.03 g cm-3 ), which facilitates the preparation of thinner electrode at high mass loadings. As a result, a high-areal capacity of above 4.2 mA h cm-2 at 0.45 mA cm-2 is obtained at a high mass loading of 7.0 mg cm-2 for LIBs, which still maintains at 2.59 mA h cm-2 after 200 cycles with a capacity retention of 98.8% at 0.89 mA cm-2 .

Doping ß-CoMoO4 Nanoplates with Phosphorus for Efficient Hydrogen Evolution Reaction in Alkaline Media.

Mass production of hydrogen by electrolysis of water largely hinges on the development of highly efficient and economical electrocatalysts for hydrogen evolution reaction (HER). Though having the merits of high earth abundance, easy availability, and tunable composition, transition-metal oxides are usually deemed as poor electrocatalysts for HER. Herein, we demonstrate that doping ß-CoMoO4 nanoplates with phosphorus can turn them into active electrocatalysts for HER. Theoretical calculation and experimental studies unravel that enhanced electrical conductivity and optimized hydrogen adsorption free energy are major causes for the improvement of intrinsic activity. As a result, only an overpotential of 138 mV is required to drive hydrogen evolving at a current density of 10 mA cm-2 in 1 M KOH for P-doped ß-CoMoO4, which outstrips many recently reported transition-metal oxides and is just slightly inferior to commercial Pt/C. This work opens a new route to tune the HER performance of transition-metal oxides.

Facile and Scalable Synthesis of Zn3V2O7(OH)2·2H2O Microflowers as a High-Performance Anode for Lithium-Ion Batteries.

The employment of nanomaterials and nanotechnologies has been widely acknowledged as an effective strategy to enhance the electrochemical performance of lithium-ion batteries (LIBs). However, how to produce nanomaterials effectively on a large scale remains a challenge. Here, the highly crystallized Zn3V2O7(OH)2·2H2O is synthesized through a simple liquid phase method at room temperature in a large scale, which is easily realized in industry. Through suppressing the reaction dynamics with ethylene glycol, a uniform morphology of microflowers is obtained. Owing to the multiple reaction mechanisms (insertion, conversion, and alloying) during Li insertion/extraction, the prepared electrode delivers a remarkable specific capacity of 1287 mA h g-1 at 0.2 A g-1 after 120 cycles. In addition, a high capacity of 298 mA h g-1 can be obtained at 5 A g-1 after 1400 cycles. The excellent electrochemical performance can be attributed to the high crystallinity and large specific surface area of active materials. The smaller particles after cycling could facilitate the lithium-ion transport and provide more reaction sites. The facile and scalable synthesis process and excellent electrochemical performance make this material a highly promising anode for the commercial LIBs.

Acetylene Black Induced Heterogeneous Growth of Macroporous CoV2O6 Nanosheet for High-Rate Pseudocapacitive Lithium-Ion Battery Anode.

Metal vanadates suffer from fast capacity fading in lithium-ion batteries especially at a high rate. Pseudocapacitance, which is associated with surface or near-surface redox reactions, can provide fast charge/discharge capacity free from diffusion-controlled intercalation processes and is able to address the above issue. In this work, we report the synthesis of macroporous CoV2O6 nanosheets through a facile one-pot method via acetylene black induced heterogeneous growth. When applied as lithium-ion battery anode, the macroporous CoV2O6 nanosheets show typical features of pseudocapacitive behavior: (1) currents that are mostly linearly dependent on sweep rate and (2) redox peaks whose potentials do not shift significantly with sweep rate. The macroporous CoV2O6 nanosheets display a high reversible capacity of 702 mAh g(-1) at 200 mA g(-1), excellent cyclability with a capacity retention of 89% (against the second cycle) after 500 cycles at 500 mA g(-1), and high rate capability of 453 mAh g(-1) at 5000 mA g(-1). We believe that the introduction of pseudocapacitive properties in lithium battery is a promising direction for developing electrode materials with high-rate capability.

Graphene Oxide Templated Growth and Superior Lithium Storage Performance of Novel Hierarchical Co2V2O7 Nanosheets.

Hierarchical Co2V2O7 nanosheets consisted of interconnected nanoparticles are synthesized by a facile method using graphene oxide as the template. The electrochemical reaction mechanism of the Co2V2O7 nanosheets is thoroughly investigated by in situ XRD and ex situ TEM. The initial Co2V2O7 transforms into CoO nanoparticles and vanadium oxides in the first cycle, and the following reversible conversion reaction mainly occurs between CoO and Co and lithiation/delithiation of the vanadium oxides. The Co2V2O7 nanosheet displays a high reversible capacity (962 mAh/g at 0.5 A/g) and remarkable high rate capability. When cycled at 5.0 A/g, a reversible capacity of 441 mAh/g can be retained after 900 cycles. The stable high capacity and excellent rate capability make the hierarchical Co2V2O7 nanosheets a promising anode material for lithium-ion batteries.

Three-Dimensional LiMnPO4·Li3V2(PO4)3/C Nanocomposite as a Bicontinuous Cathode for High-Rate and Long-Life Lithium-Ion Batteries.

Olivine-type LiMnPO4 has been extensively studied as a high-energy density cathode material for lithium-ion batteries. To improve both the ionic and electronic conductivities of LiMnPO4, a series of carbon-decorated LiMnPO4·Li3V2(PO4)3 nanocomposites are synthesized by a facile sol-gel method combined with the conventional solid-state method. The optimized composite presents a three-dimensional hierarchical structure with active nanoparticles well-embedded in a conductive carbon matrix. The combination of the nanoscale carbon coating and the microscale carbon network could provide a more active site for electrochemical reaction, as well as a highly conductive network for both electron and lithium-ion transportation. When cycled at 20 C, an initial specific capacity of 103 mA h g(-1) can be obtained and the capacity retention reaches 68% after 3000 cycles, corresponding to a capacity fading of 0.013% per cycle. The stable capacity and excellent rate capability make this carbon-decorated LiMnPO4·Li3V2(PO4)3 nanocomposite a promising cathode for lithium-ion batteries.

Long-life and high-rate Li3V2(PO4)3/C nanosphere cathode materials with three-dimensional continuous electron pathways.

Lithium-ion batteries (LIBs) are receiving considerable attention as storage devices in the renewable and sustainable energy developments. However, facile fabrication of long-life and high-rate cathode materials for LIBs is required to facilitate practical application. Here we report a favourable way to synthesize a Li3V2(PO4)3/C nanosphere cathode with three-dimensional (3D) continuous electron pathways by synergistically utilizing polyethyleneglycol (PEG) and acetylene black for carbon coating and conductive network construction. The as-prepared cathode material has a discharge capacity of 142 mA h g(-1) at 1 C rate, approaching its theoretical value (150 mA h g(-1)), and can even be cycled at a rate as high as 30 C without capacity fading. After 1000 cycles at a rate of 5 C, the as-prepared material has a capacity retention of up to 83%, and can also tolerate 5000 cycles with a considerable capacity, demonstrating excellent cycling stability. Our work shows that this material has great potential for high-energy and high-power energy storage applications, and this rational method can be applied to synthesize high-performance cathode materials on a large scale.

Cucumber-like V2O5/poly(3,4-ethylenedioxythiophene)&MnO2 nanowires with enhanced electrochemical cyclability.

Inspired by the cucumber-like structure, by combining the in situ chemical oxidative polymerization with facile soaking process, we designed the heterostructured nanomaterial with PEDOT as the shell and MnO(2) nanoparticles as the protuberance and synthesized the novel cucumber-like MnO(2) nanoparticles enriched vanadium pentoxide/poly(3,4-ethylenedioxythiophene) (PEDOT) coaxial nanowires. This heterostructured nanomaterial exhibits enhanced electrochemical cycling performance with the decreases of capacity fading during 200 cycles from 0.557 to 0.173% over V(2)O(5) nanowires at the current density of 100 mA/g. This method is proven to be an effective technique for improving the electrochemical cycling performance and stability of nanowire electrodes especially at low rate for application in rechargeable lithium batteries.

Rational synthesis of silver vanadium oxides/polyaniline triaxial nanowires with enhanced electrochemical property.

We designed and successfully synthesized the silver vanadium oxides/polyaniline (SVO/PANI) triaxial nanowires by combining in situ chemical oxidative polymerization and interfacial redox reaction based on ß-AgVO(3) nanowires. The ß-AgVO(3) core and two distinct layers can be clearly observed in single triaxial nanowire. Fourier transformed infrared spectroscopic and energy dispersive X-ray spectroscopic investigations indicate that the outermost layer is PANI and the middle layer is Ag(x)VO((2.5+0.5x)) (x < 1), which may result from the redox reaction of Ag(+) and aniline monomers at the interface. The presence of the Ag particle in a transmission electron microscopy image confirms the occurrence of the redox reaction. The triaxial nanowires exhibit enhanced electrochemical performance. This method is shown to be an effective and facile technique for improving the electrochemical performance and stability of nanowire electrodes for applications in Li ion batteries.

Hierarchical MnMoO(4)/CoMoO(4) heterostructured nanowires with enhanced supercapacitor performance.

Recent attention has been focused on the synthesis and application of complex heterostructured nanomaterials, which can have superior electrochemical performance than single-structured materials. Here we synthesize the three-dimensional (3D) multicomponent oxide, MnMoO(4)/CoMoO(4). Hierarchical heterostructures are successfully prepared on the backbone material MnMoO(4) by a simple refluxing method under mild conditions; and surface modification is achieved. We fabricate asymmetric supercapacitors based on hierarchical MnMoO(4)/CoMoO(4) heterostructured nanowires, which show a specific capacitance of 187.1 F g(-1) at a current density of 1 A g(-1), and good reversibility with a cycling efficiency of 98% after 1,000 cycles. These results further demonstrate that constructing 3D hierarchical heterostructures can improve electrochemical properties. 'Oriented attachment' and 'self-assembly' crystal growth mechanisms are proposed to explain the formation of the heterostructures.