High-Pressure-Field Induced Synthesis of Ultrafine-Sized High-Entropy Compounds with Excellent Sodium-Ion Storage.

Emerging high entropy compounds (HECs) have attracted huge attention in electrochemical energy-related applications. The features of ultrafine size and carbon incorporation show great potential to boost the ion-storage kinetics of HECs. However, they are rarely reported because high-temperature calcination tends to result in larger crystallites, phase separation, and carbon reduction. Herein, using the NaCl self-assembly template method, by introducing a high-pressure field in the calcination process, the atom diffusion and phase separation are inhibited for the general formation of HECs, and the HEC aggregation is inhibited for obtaining ultrafine size. The general preparation of ultrafine-sized (<10 nm) HECs (nitrides, oxides, sulfides, and phosphates) anchored on porous carbon composites is realized. They are demonstrated by combining advanced characterization technologies with theoretical computations. Ultrafine-sized high entropy sulfides-MnFeCoCuSnMo/porous carbon (HES-MnFeCoCuSnMo/PC) as representative anodes exhibit excellent sodium-ion storage kinetics and capacities (a high rating capacity of 278 mAh g-1 at 10 A g-1 for full cell and a high cycling capacity of 281 mAh g-1 at 20 A g-1 after 6000 cycles for half cell) due to the combining advantages of high entropy effect, ultrafine size, and PC incorporation. Our work provides a new opportunity for designing and fabricating ultrafine-sized HECs.

Regulating Metal Centers of MOF-74 Promotes PEO-Based Electrolytes for All-Solid-State Lithium-Metal Batteries.

Poly(ethylene oxide) (PEO)-based electrolytes have been extensively studied for all-solid-state lithium-metal batteries due to their excellent film-forming capabilities and low cost. However, the limited ionic conductivity and poor mechanical strength of the PEO-based electrolytes cannot prevent the growth of undesirable lithium dendrites, leading to the failure of batteries. Metal-organic frameworks (MOFs) are functional materials with a periodic porous structure that can improve the electrochemical performance of PEO-based electrolytes. However, the enhancement effect of MOFs with different metal centers and the interaction mechanism with PEO remain unclear. Herein, MOF-74s with Cu or Ni centers are prepared and used as fillers of PEO-based electrolytes. Adding 15 wt % of Cu-MOF-74 to the PEO-based electrolyte (15%Cu-MOF/P-Li) effectively improves the ionic conductivity, lithium transference number, and mechanical strength of the PEO-based electrolyte simultaneously. Furthermore, the ordered pore channels of Cu-MOF-74 provide uniform Li-ion transport pathways, facilitating homogeneous Li+ deposition. As a result, the lithium symmetric cell with 15%Cu-MOF/P-Li shows stable cycles for 1080 h at 0.1 mA cm-2 and 0.1 mAh cm-2, and the Li | 15% Cu-MOF/P-Li | LFP full cell exhibits a long cycle life up to 200 cycles at 60 °C and 0.5 C, with a capacity retention rate of 89.7%.

NaCl sealing Strategy-Assisted synthesis CoO-Co heterojunctions as efficient oxygen electrocatalysts for Zn air batteries.

Developing highly efficient, low-cost, and stable bifunctional oxygen electrocatalysts is essential for the wide popularization of rechargeable Zn-air batteries. Combining zero-dimensional metal nanoparticles with two-dimensional metal oxide nanosheets is an appealing strategy to balance performance and cost. However, the precise construction of these composites remains a great challenge, and their interaction mechanisms lack thorough study. Herein, a cobalt-oxide-based bifunctional oxygen electrocatalyst comprising a rich Co-CoO heterointerface (CoO/Co@NG) was synthesized via a NaCl sealing-assisted pyrolysis strategy. The NaCl crystals played the role of a closed nanoreactor, which facilitated the formation of a CoO-Co heterojunction. Experimental results and theoretical calculations confirmed that the ingeniously constructed heterojunction expedited the oxygen reduction reaction and oxygen evolution reaction kinetics, which is superior to Pt/C. When serving as the air electrode in an assembled liquid-state Zn-air battery, the battery shows high power density (215 mW cm-2), specific capacity (710 mAh gzn-1), and outstanding durability (720 h at 10 mA cm-2). This work provides an innovative avenue to design high-performance heterojunction electrocatalysts for perdurable Zn-air batteries.

Starch-Based Superabsorbent Hydrogel with High Electrolyte Retention Capability and Synergistic Interface Engineering for Long-Lifespan Flexible Zinc-Air Batteries.

The advent of wearable electronics has strongly stimulated advanced research into the exploration of flexible zinc-air batteries (ZABs) with high theoretical energy density, high inherent safety, and low cost. However, the half-open battery structure and the high concentration of alkaline aqueous environment pose great challenges on the electrolyte retention capability and the zinc anode stability. Herein, a starch-based superabsorbent hydrogel polymer electrolyte (SSHPE) with high ionic conductivity, electrolyte absorption and retention capabilities, strong alkaline resistance and high zinc anode stability has been designed and applied in ZABs. Experimental and calculational analyses probe into the root of the superiority of SSHPEs, confirming the significance of the carboxyl functional groups along their polymer chains. These features endow the as-fabricated ZAB a long cycle life of 300 h, much longer than that with commonly used poly(vinyl alcohol)-based electrolyte.

Decreasing Interfacial Pitfalls with Self-Grown Sheet-Like Li2 S Artificial Solid-Electrolyte Interphase for Enhanced Cycling Performance of Lithium Metal Anode.

Constructing a 3D composite Li metal anode (LMA) along with the engineering of artificial solid electrolyte interphase (SEI) is a promising strategy for achieving dendrite-free Li deposition and high cycling stability. The nanostructure of artificial SEI is closely related to the performance of the LMA. Herein, the self-grown process and morphology of in situ formed Li2 S during lithiation of Cux S is studied systematically, and a large-sized sheet-like Li2 S layer as an artificial SEI is in situ generated on the inner surface of a 3D continuous porous Cu skeleton (3DCu@Li2 S-S). The sheet-like Li2 S layer with few interfacial pitfalls (Cu/Li2 S heterogeneous interface) possesses enhanced diffusion of Li ions. And the continuous porous structure provides transport channels for lithium-ion transport. As a result, the 3DCu@Li2 S-S presents a high Coulombic efficiency (99.3%), long cycle life (500 cycles), and high-rate performance (10 mA cm-2 ). Furthermore, Li/3DCu@Li2 S anode fabricated by thermal infusion method inherits the synergistic advantages of sheet-like Li2 S and continuous porous structure. The Li/3DCu@Li2 S anode shows significantly enhanced cycling life in both liquid and solid electrolytes. This work provides a new concept to design artificial SEI for LMA with high safe and high performance.

Single-Atom Cobalt Supported on Nitrogen-Doped Three-Dimensional Carbon Facilitating Polysulfide Conversion in Lithium-Sulfur Batteries.

Single-atom catalysts (SACs) have demonstrated catalytic efficacy toward lithium polysulfide conversion in Li-S batteries. However, achieving high-density M-Nx sites with rational design by a simple method is still challenging to date. Herein, an ultrathin porous 3D carbon-supported single-atom catalyst (SACo/NDC) is synthesized with a salt-template strategy via a facile freeze-drying and one-step pyrolysis procedure and serves well as a sulfur host. The well-defined 3D carbon structure can effectively alleviate volume stress and confine polysulfides inside. Moreover, the dispersed Co-Nx sites exhibit strong chemical adsorption function and valid catalytic efficiency to LiPSs redox conversion. As a result, the SACo/NDC cathodes display enhanced long-term cycling stability and better rate capability.

Graphene oxide supported Yolk - Shell ZnS/Ni3S4 with the adjustable air layer for high performance of electromagnetic wave absorber.

Yolk-shell structure materials with the light weight, excellent impedance matching and electromagnetic wave (EMW) loss ability were widely used in the field of absorbing materials. However, the previous researches on this kind of structure always focused on the comparison between solid structure and empty structure. Different from previous studies, in this paper, the effect of yolk-shell structure with different air layer thickness on EMW absorption was studied for the first time. Graphene oxide (GO) supported yolk-shell ZnS/Ni3S4 absorbers with adjustable air layer were prepared by a simple two-step hydrothermal method. Through the equivalence of RLC resonant circuit and the elimination of the influence of polarization relaxation and conduction loss, it was found that yolk-shell structure with different air layer thickness will resonate with EMW of different frequencies, thus increasing the loss capacity of materials to EMW of this frequency. At the same time, Compared with the solid structure, the yolk-shell structure can not only make the material lighter, but also cause multiple reflections and scattering of EMW. Noteworthy, yolk-shell structure composite material exhibits the maximum reflection loss (RL) of -63.0 dB at 4.8 GHz and an effective absorption bandwidth (EAB) of 4.1 GHz at a thickness of 1.6 mm. This research provides an idea and basis for the design of absorbing materials that respond to different frequency EMW.

Design of conical hollow ZnS arrays vertically grown on carbon fibers for lightweight and broadband flexible absorbers.

High-performance electromagnetic (EM) absorbers are necessary for military and industry application in view of the extensive utilization of EM devices. Carbon fibers (CFs) have been considered as promising candidates in electromagnetic wave (EMW) absorption materials, while the single carbon fiber material cannot achieve satisfactory EMW absorption performance because of its limited impedance matching. Herein, electrodeposition and hydrothermal methods were used to fabricate vertical hollow ZnS nanoarrays on carbon cloth (CC) substrate, and then one kind of novel flexible EM composite absorbers with excellent performance was obtained through adjusting morphology of hollow ZnS nanoarrays by easily changing the synthesis parameters of the precursor. Noteworthy, the miniaturized cone-shaped hollow ZnS nanoarray composite absorber shows excellent EMW absorption performance of strong absorption and wide absorption band. The maximum reflection loss value is -52.5 dB and the effective absorption bandwidth reaches 5.1 GHz when the thickness is only 1.9 mm. At the same time, the composite possesses the characteristics of light weight and thin thickness. The excellent properties of the composite absorbers are mainly attributed to their morphological structure. The unique hollow ZnS nanoarray structure enhances the interface polarization and multiple reflections, meanwhile also giving it the properties of metamaterials with resonant absorption. Furthermore, the adjustment of the ZnS nanoarray morphology can not only change the transmission behavior of EMW but also affect the resonance frequency and intensity of the ZnS nanoarray unit. This study obtains high-performance absorbing materials with flexible characteristics as well as highlights the importance of the adjustment of the morphological structure to improve the EMW absorption performance.

Enhanced Cyclability of Cr8O21 Cathode for PEO-Based All-Solid-State Lithium-Ion Batteries by Atomic Layer Deposition of Al2O3.

Cr8O21 can be used as the cathode material in all-solid-state batteries with high energy density due to its high reversible specific capacity and high potential plateau. However, the strong oxidation of Cr8O21 leads to poor compatibility with polymer-based solid electrolytes. Herein, to improve the cycle performance of the battery, Al2O3 atomic layer deposition (ALD) coating is applied on Cr8O21 cathodes to modify the interface between the electrode and the electrolyte. X-ray photoelectron spectroscopy, scanning electron microscope, transmission electron microscope, and Fourier transform infrared spectroscopy, etc., are used to estimate the morphology of the ALD coating and the interface reaction mechanism. The electrochemical properties of the Cr8O21 cathodes are investigated. The results show that the uniform and dense Al2O3 layer not only prevents the polyethylene oxide from oxidization but also enhances the lithium-ion transport. The 12-ALD-cycle-coated electrode with approximately 4 nm Al2O3 layer displays the optimal cycling performance, which delivers a high capacity of 260 mAh g-1 for the 125th cycle at 0.1C with a discharge-specific energy of 630 Wh kg-1.

Balancing Strength and Ductility in Al Matrix Composites Reinforced by Few-Layered MoS2 through In-Situ Formation of Interfacial Al12Mo.

In this work, few-layered MoS2 (FLM) nanosheet-reinforced Al matrix composites are developed through powder metallurgy and hot extrusion. The microstructure, mechanical properties, and strengthening mechanisms have been systematically investigated. It is found that Al12Mo and Al2S3 can be formed in-situ during the sintering process, resulting in the improvement of interfacial bonding between FLM and Al matrix. With 1.5 wt.% of FLM addition, an improved tensile strength of 234 MPa with a high elongation of 17% can be obtained. Moreover, the strengthening mechanisms are also demonstrated to be grain refinement, dislocation strengthening, and load transfer, and the calculation indicates that load transfer is the main contribution factor. This work will inspire more new designs of metal matrix composites with balanced strength and ductility.

W Clusters In Situ Assisted Synthesis of Layered Carbon Nanotube Arrays on Graphene Achieving High-Rate Performance.

W atoms/clusters are employed to in situ assist the development of layered vertically aligned carbon nanotube arrays (VACNTs) through hot-filament-assisted chemical vapor deposition (HFCVD) with liquid binary Fe3O4/AlOx catalysts. The hot W filament was utilized to in situ evaporate atomic W and form W clusters on Fe catalysts, which have a strong impact on the growth of layered VACNT arrays. The migration and Ostwald ripening of Fe catalysts are found to be suppressed immediately with more W clusters deposition during CNT growth. Through controlling the deposition of W clusters, the electrochemical energy storage performance of as-prepared layered VACNT arrays is also tunable as electrodes of ion-based supercapacitors. The layered VACNT arrays can achieve a high capacity of 83.1 mF cm-2 and possess desirable rate performance due to the suitable hot filament condition (55 W for 90 s). This work provides a new perspective to in-depth understand the behavior of W filament during HFCVD and the significant role of the in situ generated W clusters on the growth of CNTs by maintaining the catalytic activity and structure of catalysts.

Expression and role of specificity protein 1 and collagen I in recurrent pterygial tissues.

AIM: To investigate the expression profiles of the transcription factor specificity protein 1 (Sp1) and collagen I in recurrent pterygial tissues. What is more, to compare the changes of Sp1 and collagen I among primary pterygial tissue, recurrent pterygial tissue and conjunctival tissue. METHODS: In the prospective study, we collected the pterygial tissues of 40 patients who underwent resection of primary pterygial tissue and recurrent pterygial tissue, and the conjunctival tissues of 10 patients with enucleation due to trauma. The relative expression levels of Sp1 and collagen I were analyzed by reverse transcription quantitative-polymerase chain reaction and Western blot. Paired t-test was performed to compare the Sp1 and collagen I of recurrent pterygial tissues, as well as the primary pterygial tissues and conjunctival tissues. In further, Pearson's hypothesis testing of correlation coefficients was used to compare the correlations of Sp1 and Collagen I. RESULTS: The content of Sp1 and collagen I mRNA and protein was significantly greater in recurrent pterygial tissue than that was in primary and conjunctival tissue (P<0.05). There was a positive correlation between the mRNA and protein levels of Sp1 and collagen I in recurrent pterygial tissues (protein: r=0.913, P<0.05; mRNA: r=0.945, P<0.05). CONCLUSION: Sp1 and collagen I are expressed in normal conjunctival, primary, and recurrent pterygial tissues, but expression is significantly greater in the latter. Sp1 and collagen I may be involved in the regulation of the development of recurrent pterygium.

Heterostructure Engineering of Core-Shelled Sb@Sb2 O3 Encapsulated in 3D N-Doped Carbon Hollow-Spheres for Superior Sodium/Potassium Storage.

In this work, the core-shelled Sb@Sb2 O3 heterostructure encapsulated in 3D N-doped carbon hollow-spheres is fabricated by spray-drying combined with heat treatment. The novel core-shelled heterostructures of Sb@Sb2 O3 possess a mass of heterointerfaces, which formed spontaneously at the core-shell contact via annealing oxidation and can promote the rapid Na+ /K+ transfer. The density functional theory calculations revealed the mechanism and significance of Na/K-storage for the core-shelled Sb@Sb2 O3 heterostructure, which validated that the coupling between the high-conductivity of Sb and the stability of Sb2 O3 can relieve the shortcomings of the individual building blocks, thereby enhancing the Na/K-storage capacity. Furthermore, the core-shell structure embedded in the 3D carbon framework with robust structure can further increase the electrode mechanical strength and thus buffer the severe volume changes upon cycling. As a result, such composite architecture exhibited a high specific capacity of ≈573 mA h g-1 for sodium-ion battery (SIB) anode and ≈474 mA h g-1 for potassium-ion battery (PIB) anode at 100 mA g-1 , and superior rate performance (302 mA h g-1 at 30 A g-1 for SIB anode, while 239 mA h g-1 at 5 A g-1 for PIB anode).

A powder-metallurgy-based strategy toward three-dimensional graphene-like network for reinforcing copper matrix composites.

Three-dimensional graphene network is a promising structure for improving both the mechanical properties and functional capabilities of reinforced polymer and ceramic matrix composites. However, direct application in a metal matrix remains difficult due to the reason that wetting is usually unfavorable in the carbon/metal system. Here we report a powder-metallurgy based strategy to construct a three-dimensional continuous graphene network architecture in a copper matrix through thermal-stress-induced welding between graphene-like nanosheets grown on the surface of copper powders. The interpenetrating structural feature of the as-obtained composites not only promotes the interfacial shear stress to a high level and thus results in significantly enhanced load transfer strengthening and crack-bridging toughening simultaneously, but also constructs additional three-dimensional hyperchannels for electrical and thermal conductivity. Our approach offers a general way for manufacturing metal matrix composites with high overall performance.

Dynamic changes of periostin and collagen I in the sclera during progressive myopia in guinea pigs / Alterações dinâmicas de periostina e colágeno I na esclera durante miopia progressiva em cobaias

ABSTRACT Purpose: To investigate periostin and collagen I expression during a scleral remodeling in myopic eyes and to determine their role in collagen remodeling of the myopic sclera. Methods: Fifty one-week-old guinea pigs were divided into the control and form-deprivation myopia (FDM) groups. The eyes of animals in the form-deprivation myopia group were covered for 2, 4, and 8 weeks, or were covered for 4 weeks and then uncovered for 2 weeks. The diopters and axial lengths in the eyes in each group of guinea pigs were measured. Immunohistochemistry and reverse transcription polymerase chain reaction were used to detect the relative protein and mRNA expressions of periostin and collagen I in the scleral tissues of guinea pig. Results: Before masking, guinea pigs in the control and form-deprivation myopia groups were hypermetropic and did not differ significantly (p>0.05). Hypermetropic refraction in the control group gradually decreased. In guinea pigs from the form-deprivation myopia group, the refractive power gradually changed from +2.14 ± 0.33 D to -7.22 ± 0.51 D, and the axial length gradually changed from 5.92 ± 0.37 mm to 8.05 ± 0.34 mm from before until the end of masking. Before covering, no significant difference was observed in the relative collagen I and periostin mRNA and protein expression levels in the sclera of the guinea pig control and form-deprivation myopia groups (p>0.05). The relative collagen I and periostin protein and mRNA expression levels in the sclera of guinea pigs in the form-deprivation myopia group at 2, 4, and 8 weeks, and after covering the eyes for 4 weeks followed by uncovering for 2 weeks, were significantly lower than those in the control group (p<0.05). The collagen I and periostin mRNA expression levels were positively correlated with protein expression levels in the sclera of guinea pigs (protein: r=0.936, p<0.05; mRNA: r=0.909, p<0.05). Conclusions: Periostin was expressed in the myopic sclera of guinea pigs, and changes in periostin and collagen I expression were highly consistent. Periostin and collagen I may be involved in the regulation of scleral remodeling in myopia.

RESUMO Objetivo: Investigar a expressão da periostina e do colágeno I durante o remodelamento escleral em olhos míopes e determinar seu papel na remodelação do colágeno da esclera miópica. Métodos: Cinquenta cobaias com uma semana de idade foram divididas em grupo controle e miopia de privação de forma. Os olhos dos animais no grupo de miopia de privação de forma foram cobertos por 2, 4 e 8 semanas, ou foram cobertos por 4 semanas e depois descobertas por 2 semanas. As dioptrias e comprimentos axiais dos olhos em cada grupo de cobaias foram medidos. A imunohistoquímica e a reação em cadeia da polimerase com transcrição reversa foram utilizadas para detectar as expressões relativas de proteína e mRNA de periostina e colágeno I em tecidos esclerais das cobaias. Resultados: Antes do mascaramento, as cobaias nos grupos controle e miopia de privação de forma eram hipermetrópicas e não diferiam significativamente (p>0,05). A refração hipermetrópica no grupo controle diminuiu gradualmente. Nas cobaias do grupo de miopia de privação de forma, a potência de refração mudou gradualmente de +2,14 ± 0,33 D para -7,22 ± 0,51 D e o comprimento axial mudou gradualmente de 5,92 ± 0,37 mm para 8,05 ± 0,34 mm desde antes até o final do mascaramento. Antes do mascaramento, nenhuma diferença significativa foi observada nos níveis de expressão de mRNA e proteína de colágeno I e periostina na esclera dos grupos controle e miopia de privação de forma (p>0,05). Os níveis relativos de expressão de colágeno I e proteína periostina e mRNA na esclera de cobaias no grupo de miopia de privação de forma em 2, 4 e 8 semanas, e após cobertura dos olhos por 4 semanas seguido de descoberta por 2 semanas, foram significativamente menores que aqueles no grupo controle (p<0,05). Os níveis de expressão de mRNA, colágeno I e proteína periostina foram positivamente correlacionados com os níveis de expressão de proteína na esclera das cobaias (proteína: r=0,936, p<0,05; mRNA: r=0,909, p<0,05). Conclusões: A periostina foi expressa na esclerótica míope de cobaias e as alterações na expressão de periostina e colágeno I foram altamente consistentes. A periostina e o colágeno I podem estar envolvidos na regulação do remodelamento escleral na miopia.

Octopus-Inspired Design of Apical NiS2 Nanoparticles Supported on Hierarchical Carbon Composites as an Efficient Host for Lithium Sulfur Batteries with High Sulfur Loading.

Developing high-performance Li-S batteries with high sulfur loading is highly desirable for practical application and remains a major challenge. To achieve this goal, the following requirements for designing carbon/metal compound composites need to be met: (i) the carbon materials need to exhibit suitable specific surface area, void structure, and electrical conductivity; (ii) the weight content of the metal compounds should be low; and (iii) the metal compounds need to show a strong adsorption and efficient electrocatalytic function for LiPSs. In this study, inspired by the body structure of an octopus, a new carbon/NiS2 hierarchical composite is reported, in which the apical NiS2 nanoparticles (0D) on a 1D carbon nanotubes (CNTs) are supported on a three-dimensional carbon (3DC) framework (3DC-CNTs-NiS2). The 3DC-CNTs-NiS2 composite has a high specific surface area (271 m2 g-1), good electrical conductivity, and low NiS2 content (9.2 wt %), and the apical NiS2 nanoparticles are capable of adsorption and electrocatalysis toward LiPSs, demonstrated by both electrochemical characterization and theoretical calculation. When used as a cathode host of the Li-S battery, it exhibits an ultra-stable cycling performance with a fade rate of 0.043% per cycle over 1000 cycles; even with a high S loading (6.5 mg cm-2 with 90 wt % of S), the soft package battery delivers a high area capacity of 5.0 mAh cm-2 under the E/S ratio of 5 µLE mg-1s. This work provides a new approach to design and fabricate multi-functional S hosts with high S loading.

Enhanced Shielding Performance of Layered Carbon Fiber Composites Filled with Carbonyl Iron and Carbon Nanotubes in the Koch Curve Fractal Method.

Layered carbon fiber composites (CFC) with enhanced shielding effectiveness (SE) were prepared with mixed fillers of carbon nanotubes (CNTs) and carbonyl iron powders (CIPs) in the form of a Koch curve fractal. In the layered composite structure, glass fiber (GF) cloth was used in the wave-transmissive layer (WTL), and the carbon fiber (CF) cloth was used in the supporting layer (SL). Between WTL and SL, CNTs and CIPs were distributed in epoxy resin in the form of a Koch curve fractal to act as an absorbing layer (AL), and copper foil was used as a reflective layer (RL) and bonded at the bottom of the whole composites. The layered structure design and excellent interlayer interface integration obviously improved the SE performance of the CFC. The SE of different samples was investigated, and the results show that, with the increase in the number (n) of Koch curve fractals, the SE of the samples enhanced in the low frequency scope (1-5 GHz). The sample with n = 2 has the highest SE value of 73.8 dB at 2.3 GHz. The shielding performance of the fractal sample filled by CNTs and CIPs simultaneously has a comprehensive improvement in the whole scope of 1-18 GHz, especially for the sample with n = 2. The cumulative bandwidth value of the SE exceeding 55 dB is about 14.3 GHz, accounting for 85% of the whole frequency scope, indicating the composite fabricated in this paper is an electromagnetic shielding material with great prospect.

Dynamic changes of periostin and collagen I in the sclera during progressive myopia in guinea pigs.

PURPOSE: To investigate periostin and collagen I expression during a scleral remodeling in myopic eyes and to determine their role in collagen remodeling of the myopic sclera. METHODS: Fifty one-week-old guinea pigs were divided into the control and form-deprivation myopia (FDM) groups. The eyes of animals in the form-deprivation myopia group were covered for 2, 4, and 8 weeks, or were covered for 4 weeks and then uncovered for 2 weeks. The diopters and axial lengths in the eyes in each group of guinea pigs were measured. Immunohistochemistry and reverse transcription polymerase chain reaction were used to detect the relative protein and mRNA expressions of periostin and collagen I in the scleral tissues of guinea pig. RESULTS: Before masking, guinea pigs in the control and form-deprivation myopia groups were hypermetropic and did not differ significantly (p>0.05). Hypermetropic refraction in the control group gradually decreased. In guinea pigs from the form-deprivation myopia group, the refractive power gradually changed from +2.14 ± 0.33 D to -7.22 ± 0.51 D, and the axial length gradually changed from 5.92 ± 0.37 mm to 8.05 ± 0.34 mm from before until the end of masking. Before covering, no significant difference was observed in the relative collagen I and periostin mRNA and protein expression levels in the sclera of the guinea pig control and form-deprivation myopia groups (p>0.05). The relative collagen I and periostin protein and mRNA expression levels in the sclera of guinea pigs in the form-deprivation myopia group at 2, 4, and 8 weeks, and after covering the eyes for 4 weeks followed by uncovering for 2 weeks, were significantly lower than those in the control group (p<0.05). The collagen I and periostin mRNA expression levels were positively correlated with protein expression levels in the sclera of guinea pigs (protein: r=0.936, p<0.05; mRNA: r=0.909, p<0.05). CONCLUSIONS: Periostin was expressed in the myopic sclera of guinea pigs, and changes in periostin and collagen I expression were highly consistent. Periostin and collagen I may be involved in the regulation of scleral remodeling in myopia.

An in-plane Co9S8@MoS2 heterostructure for the hydrogen evolution reaction in alkaline media.

Transition metal sulfides have emerged as promising hydrogen evolution reaction (HER) electrocatalysts in acidic media due to high intrinsic activity. They exhibit inferior HER activity in alkaline media, however, owing to the sluggish water dissociation kinetics. Herein, in-plane MoS2/Co9S8 heterostructures are in situ grown on three-dimensional carbon network substrates with interconnected hierarchical pores by one-step pyrolysis to enhance the alkaline HER activity. The experiment results reveal that the HER kinetics of MoS2 is accelerated after the construction of heterostructures. The synthesized MoS2/Co9S8 heterostructures anchored on a three-dimensional interconnected hierarchical pore carbon network exhibit a lower overpotential of 177 mV than MoS2 (252 mV) at 10 mA cm-2 for the HER in 1 M KOH. The enhanced catalytic performance is mainly attributed to the accelerated water dissociation kinetics on the interface of MoS2 and Co9S8. In combination with DFT calculations, it is revealed that assembling the interface construction synergistically favors the chemisorption of protons and the cleavage of the O-H bonds of the H2O molecule, thus accelerating the kinetics of the HER. Moreover, the three-dimensional interconnected hierarchical pore carbon (3DC) network structure is beneficial for the circulation of the electrolyte and H2 spillover. This study demonstrates the present strategy as a facile route for fabricating efficient HER catalysts.