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Developing anode materials with high specific capacity and cycling stability is vital for improving thin‐film lithium‐ion batteries. Thin‐film zinc oxide (ZnO) holds promise due to its high specific capacity, but it suffers from volume changes and structural stress during cycling, leading to poor battery performance. In this research, we ingeniously combined polytetrafluoroethylene (PTFE) with ZnO using a radio frequency (RF) magnetron co‐sputtering method, ensuring a strong bond in the thin‐film composite electrode. PTFE effectively reduced stress on the active material and mitigated volume change effects during Li+ ion intercalation and deintercalation. The composite thin films are thoroughly characterized using advanced techniques such as X‐ray diffraction, scanning electron microscopy, and X‐ray photoelectron spectroscopy for investigating correlations between material properties and electrochemical behaviors. Notably, the ZnO/PTFE thin‐film electrode demonstrated an impressive specific capacity of 1305 mAh g−1 (=7116 mAh cm−3) at a 0.5C rate and a remarkable capacity retention of 82% from the 1st to the 100th cycle, surpassing the bare ZnO thin film (50%). This study provides valuable insights into using binders to stabilize active materials in thin‐film batteries, enhancing battery performance. [ABSTRACT FROM AUTHOR]

The layered δ‐MnO2 (dMO) is an excellent cathode material for rechargeable aqueous zinc‐ion batteries owing to its large interlayer distance (~0.7 nm), high capacity, and low cost; however, such cathodes suffer from structural degradation during the long‐term cycling process, leading to capacity fading. In this study, a Co‐doped dMO composite with reduced graphene oxide (GC‐dMO) is developed using a simple cost‐effective hydrothermal method. The degree of disorderness increases owing to the hetero‐atom doping and graphene oxide composites. It is demonstrated that layered dMO and GC‐dMO undergo a structural transition from K‐birnessite to the Zn‐buserite phase upon the first discharge, which enhances the intercalation of Zn2+ ions, H2O molecules in the layered structure. The GC‐dMO cathode exhibits an excellent capacity of 302 mAh g−1 at a current density of 100 mA g−1 after 100 cycles as compared with the dMO cathode (159 mAh g−1). The excellent electrochemical performance of the GC‐dMO cathode owing to Co‐doping and graphene oxide sheets enhances the interlayer gap and disorderness, and maintains structural stability, which facilitates the easy reverse intercalation and de‐intercalation of Zn2+ ions and H2O molecules. Therefore, GC‐dMO is a promising cathode material for large‐scale aqueous ZIBs. [ABSTRACT FROM AUTHOR]

A suitable interface between the electrode and electrolyte is crucial in achieving highly stable electrochemical performance for Li‐ion batteries, as facile ionic transport is required. Intriguing research and development have recently been conducted to form a stable interface between the electrode and electrolyte. Therefore, it is essential to investigate emerging knowledge and contextualize it. The nanoengineering of the electrode‐electrolyte interface has been actively researched at the electrode/electrolyte and interphase levels. This review presents and summarizes some recent advances aimed at nanoengineering approaches to build a more stable electrode‐electrolyte interface and assess the impact of each approach adopted. Furthermore, future perspectives on the feasibility and practicality of each approach will also be reviewed in detail. Finally, this review aids in projecting a more sustainable research pathway for a nanoengineered interphase design between electrode and electrolyte, which is pivotal for high‐performance, thermally stable Li‐ion batteries. [ABSTRACT FROM AUTHOR]

Lithium‐ion batteries (LIBs) and beyond‐LIB systems exhibit properties that are determined by electrochemical reactions occurring in their four essential components—the cathode, anode, electrolyte, and separator. Advanced analytical methods such as differential electrochemical mass spectrometry (DEMS) can assist in understanding the electrochemical behavior, which can help in advancing battery technologies. Recent studies have shown that the DEMS‐enabled real‐time gas analysis of electrochemical reactions can provide valuable information on aspects such as gaseous reactants or (side) products, which cannot be obtained appropriately through other characterization techniques. This review aims to provide a comprehensive overview of the latest developments and advancements in the use of DEMS as a rapid, operando gas‐monitoring method for advanced rechargeable battery systems. Moreover, the significance of DEMS in current and future battery development is also discussed and insights are provided into the various battery chemistries that can benefit from DEMS applications. This review is intended to help readers understand the potential of DEMS to drive innovation in the battery industry. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs), featuring ordered nanopores with numerous accessible redox sites, have drawn much attention as promising electrode materials for rechargeable batteries. Thus far, however, COF‐based battery electrodes have exhibited limited capacity and unsatisfactory cycling stability due to the unwanted side reactions over their large surface area. Herein, a fluorine‐rich covalent organic framework (F‐COF) as an electrode material with improved stability and performance for potassium‐ion batteries is developed. The fluorinated COF not only stabilizes intercalation kinetics of K+ ions but also reinforces its electron affinity and conductivity, improving the reversibility of bond transitions during discharge–charge cycles. As a result, F‐COF affords a high specific capacity (95 mAh g−1 at fast rates up to 5 C) and excellent cycling stability (5000 cycles with ≈99.7% capacity retention), outperforming the pristine COF‐based electrodes devoid of F atoms. Notably, the experimental capacity of F‐COF approaches its theoretical value, confirming that a large proportion of electroactive sites are being actively utilized. Altogether, this work addresses the significant role of F atoms in improving the K+‐ion storage capability of COFs and provides the rational design principles for the continued development of stable and high‐performance organic electrode materials for energy storage devices. [ABSTRACT FROM AUTHOR]

The lithium metal anode is notoriously unstable and reactive to electrolytes, forming brittle solid‐electrolyte interphase (SEI) layers with uneven distribution, exacerbating Li dendrites that ultimately limit the battery life. Here, this work passivates Li metal with electrolyte‐swellable polymer nanolayers deposited monolithically by the initiated chemical vapor deposition (iCVD) to reinforce the native SEI layers and stabilize their interface. The 100 nm iCVD poly(dimethylaminomethyl styrene) (pDMAMS) layer is swelled by 264% under a carbonate electrolyte, establishing the electrolyte‐filled soft scaffold for Li‐ion transport. Notably, the solvogel accommodates homogeneous Li2O‐free and Li2CO3‐rich native SEI layers, providing a record‐high Li‐ion transference number of 0.95 and ionic conductivity of 6.54 mS cm−1. The developed pDMAMS‐Li anodes extend the cycle life by 550% in Li–Li symmetric cells and 600% in LiNi0.6Mn0.2Co0.2O2 full cells compared to pristine Li metal. The mechanistic details of the swollen‐soft‐scaffold strategy are elucidated by depth profile analysis of the pDMAMS homopolymer compared to pDMAMS/electrolyte‐phobic copolymers, providing new insights to manage the interface of liquid‐state electrolyte and solid‐state Li metal by using a novel class of bifunctional solvogel. [ABSTRACT FROM AUTHOR]

Osteoporotic bone regeneration is a challenging process which involves the occurrence of sophisticated interactions. Although various polymeric scaffolds have been proposed for bone repair, research on osteoporotic bone regeneration remains practically limited. In particular, achieving satisfactory bone regeneration when using osteoporotic drugs is challenging including bisphosphonates. Here, a novel nitric oxide‐releasing bioinspired scaffold with bioactive agents for the exquisite regeneration of osteoporotic bone is proposed. The bone‐like biomimetic poly(lactic‐co‐glycolic acid) scaffold is first prepared in combination with organic/inorganic ECM and magnesium hydroxide as the base implant material. Nanoparticles containing bioactive agents of zinc oxide (ZO), alendronate, and BMP2 are incorporated to the biomimetic scaffold to impart multifunctionality such as anti‐inflammation, angiogenesis, anti‐osteoclastogenesis, and bone regeneration. Especially, nitric oxide (NO) generated from ZO stimulates the activity of cGMP and protein kinase G; in addition, ZO downregulates the RANKL/osteoprotegerin ratio by suppressing the Wnt/β‐catenin signaling pathway. The new bone is formed much better in the osteoporotic rat model than in the normal model through the regulation of bone homeostasis via the scaffold. These synergistic effects suggest that such a bioinspired scaffold could be a comprehensive way to regenerate exceptionally osteoporotic bones. [ABSTRACT FROM AUTHOR]

Due to the unique properties which are considerably different from macro‐scale or bulk materials, 1D) nanostructures have received great interests. In particular, they have greatly contributed to building next‐generation batteries by providing beneficial features such as short ion/electron pathways, structural versatility (i.e., formation of 3D current collectors, free‐standing electrodes, and separators), and excellent stress relaxation. Owing to these definite advantages, 1D nanostructure is often followed by discovery of new electrode materials. This review provides a systematic overview of the state‐of‐the‐art research progresses on 1D nanostructures, which are extensively used for rechargeable batteries. Specifically, a brief introduction of some important 1D nanostructuring methods is started and then, in situ structural characterizations using 1D nanostructures are summarized, which allow a great step forward in atomic‐scale monitoring of reaction kinetics and observing dynamic structural evolution of electrode materials. 1D nanstructuring in solid‐state electrolytes and stabilization of metal anodes are also highlighted which are not only substantially important in current research trends for future batteries but also rarely discussed in previous reviews. At the end, critical perspective and future research direction of 1D nanoengineering for future batteries are suggested. [ABSTRACT FROM AUTHOR]

This review reports on the most updated technological aspects of Li–air battery cathode materials. It provides the reader with recent developments, alongside critical views. The requirements for air‐cathodes, as well as the classification and characterization of carbon‐based and carbon‐free air cathodes, are listed. The effects of two major substituent groups of materials, namely carbon and advanced materials (metals, metal‐oxides, metal‐carbides, and metal‐nitrides) aimed at replacing carbon, are discussed in terms of their chemical and electrochemical stability. The report covers aspects of surface chemistry and structure influence on the electrolyte and discharge products stability. The review also reports on the efforts to suppress side reactions and deterioration of the polymeric binders (if a composite electrode is being considered). This is recognized as a means to enhance Li–air battery performance. The report concludes with an outlook and perspective, providing the readers with some insight on other factors and their impact on the long road toward a viable air‐cathode suitable for Li–air battery operations. [ABSTRACT FROM AUTHOR]

Purpose: To compare the non‐invasive keratographic tear film break‐up time (NIKBUT) and the location and pattern of non‐invasive keratographic tear film break‐up between normal group and each group of three dry eye disease (DED) subtypes. Methods: We enrolled 55 normal subjects and 250 patients with DED, who underwent tear meniscus height and NIKBUT measurements using the Keratograph® 5M. Ocular surface parameter assessments such as the fluorescein tear break‐up time, ocular surface staining, Schirmer's test, and lid margin and meibomian gland examinations were performed, and the ocular surface disease index was determined. These parameters, including the proportion of the first tear film break‐up location and simultaneous multiple tear film break‐up pattern, were compared amongst the normal and DED subtypes. Results: Aqueous‐deficient dry eye disease (ADDE) and ADDE/meibomian gland dysfunction (MGD) subtypes showed lower NIKBUTs than those of the normal group, whilst NIKBUTs of the MGD subtype did not differ from those of the normal group. The NIKBUTs showed a good diagnostic ability in diagnosing dry eye except MGD only. The occurrence of the first tear film break‐up in the central location was significantly higher in both the ADDE and ADDE/MGD subtypes, comprising approximately 40% in both subtypes (p < 0.001). The proportion of a simultaneous multiple tear film break‐up pattern was higher in the ADDE and ADDE/MGD subtypes, at 60.9% and 45.5%, respectively (p < 0.001). Conclusion: The NIKBUTs and the location and pattern of non‐invasive tear film break‐up were different between normal group and each group of three DED subtypes. [ABSTRACT FROM AUTHOR]

Abstract: Edges of 2D transition metal dichalcogenides (TMDs) are well known as highly reactive sites, thus researchers have attempted to maximize the edge site density of 2D TMDs. In this work, metal‐organic framework (MOF) templates are introduced to synthesize few‐layered WS2 nanoplates (a lateral dimension of ≈10 nm) confined in Co, N‐doped hollow carbon nanocages (WS2_Co‐N‐HCNCs), for highly sensitive NO2 gas sensors. WS2 precursors are assembled in the surface cavity of Co‐based zeolite imidazole framework (ZIF‐67) and subsequent pyrolysis produced WS2_Co‐N‐HCNCs. During the pyrolysis, the carbonized ZIF‐67 are doped by Co and N elements, and the growth of WS2 is effectively suppressed, creating few‐layered WS2 nanoplates functionalized Co‐N‐HCNCs. The WS2_Co‐N‐HCNCs exhibit outstanding NO2 sensing characteristics at room temperature, in terms of response (48.2% to 5 ppm), selectivity, response and recovery speed, and detection limit (100 ppb). These results are attributed to the enhanced adsorption and desorption kinetics of NO2 on abundant WS2 edges, confined in the gas permeable HCNCs. This work opens up an efficient way for the facile synthesis of edge abundant few‐layered TMDs combined with porous carbon matrix via MOF templating route, for applications relying on highly active sites. [ABSTRACT FROM AUTHOR]

Importance: Corneal refractive surgery may impact meibomian gland and tear film in post-refractive surgery patients. Background: To compare ocular surface parameters between post-refractive surgery patients and normal controls. Design: Cross-sectional single centre study. Participants: A total of 120 eyes of 120 subjects were divided into three groups: (i) 60 controls and 60 patients underwent corneal refractive surgery at least 12 months ago; (ii) 30 post-laser in-situ keratomileusis (LASIK) patients and (iii) 30 post-laser epithelial keratomileusis (LASEK)/photo-refractive keratectomy (PRK) patients. Methods: Tear meniscus height, non-invasive keratographic tear film break-up time and meibography were measured using the Keratograph® 5M. Fluorescein break-up time, ocular surface staining, examination of lid margins and meibomian glands, Schirmer's test and Ocular Surface Disease Index questionnaire were performed. Main Outcome Measures: Ordinary logistic regression was performed to evaluate the impact of clinical variables including refractive surgery on the meiboscores. Results: In post-LASIK patients, ocular surface parameters including Ocular Surface Disease Index scores, fluorescein break-up time and staining scores, except Schirmer's scores, were significantly worse than those in controls (P < 0.050). Ocular surface staining scores in post-LASEK/PRK patients was higher than that in the controls (P = 0.001). In post-refractive surgery patients, grade of meibomian gland parameters and meiboscores were worse than those of controls (all P < 0.050). Histories of refractive surgery were associated with high meiboscore (β = 1.100, P = 0.043 for LASIK and β = 1.039, P = 0.042 for LASEK/PRK). Conclusions and relevance: Corneal refractive surgery may adversely affect the ocular surface, and a reduction of functional meibomian glands can contribute to chronic tear film dysfunction after corneal refractive surgery. [ABSTRACT FROM AUTHOR]

Nanostructuring has significantly contributed to alleviating the huge volume expansion problem of the Ge anodes. However, the practical use of nanostructured Ge anodes has been hindered due to several problems including a low tap density, poor scalability, and severe side reactions. Therefore, micrometer-sized Ge is desirable for practical use of Ge-based anode materials. Here, micronized Ge3N4 with a high tap density of 1.1 mg cm−2 has been successfully developed via a scalable wet oxidation and a subsequent nitridation process of commercially available micrometer-sized Ge as the starting material. The micronized Ge3N4 shows much-suppressed volume expansion compared to micrometer-sized Ge. After the carbon coating process, a thin carbon layer (≈3 nm) is uniformly coated on the micronized Ge3N4, which significantly improves electrical conductivity. As a result, micronized Ge3N4@C shows high reversible capacity of 924 mAh g−1 (2.1 mAh cm−2) with high mass loading of 3.5 mg cm−2 and retains 91% of initial capacity after 300 cycles at a rate of 0.5 C. Additionally, the effectiveness of Ge3N4@C as practical anodes is comprehensively demonstrated for the full cell, showing stable cycle retention and especially excellent rate capability, retaining 47% of its initial capacity at 0.2 C for 12 min discharge/charge condition. [ABSTRACT FROM AUTHOR]

Background To investigate the possible mechanisms by which cataract surgery aggravates meibomian gland dysfunction (MGD), we evaluated the changes in tear cytokines and ocular surface parameters after cataract surgery according to the preoperative MGD grade. Design Prospective, observational case series. Participants A total of 50 eyes from 50 patients who underwent cataract surgery were included. Methods Patients were classified into two groups: Group I had no or minimal MGD, and group II had grades 2-4 MGD. Ocular surface parameters were measured, including tear film break-up time, Schirmer I test, ocular surface staining and Ocular Surface Disease Index, and tear cytokine levels were measured. Main Outcome Measures The main outcomes were changes in ocular surface parameters and inflammatory tear cytokine concentrations. Results In group II, preoperative MGD grade, ocular surface staining, tear film break-up time and Ocular Surface Disease Index were worse, and mean interleukin (IL)-2, IL-6 and TNF-α levels were higher than those of group I. MGD and ocular surface parameters were worsened to a greater degree after surgery in group II than in group I ( P < 0.050). In group II, IL-6 and TNF-α levels significantly increased at postoperative 1 month, and there were significant correlations between changes in ocular surface parameters and tear cytokines (IL-2, IL-6 and TNF-α; P < 0.050). Conclusions The extent to which the MGD grade was aggravated following cataract surgery differed based on preoperative MGD grade. Preoperative MGD and ocular surface status should be carefully evaluated. [ABSTRACT FROM AUTHOR]

The development of efficient bifunctional catalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is a key issue pertaining high performance Li-O2 batteries. Here, we propose a heterogeneous electrocatalyst consisting of LaMnO3 nanofibers (NFs) functionalized with RuO2 nanoparticles (NPs) and non-oxidized graphene nanoflakes (GNFs). The Li-O2 cell employing the tailored catalysts delivers an excellent electrochemical performance, affording significantly reduced discharge/charge voltage gaps (1.0 V at 400 mA g−1), and superior cyclability for over 320 cycles. The outstanding performance arises from (1) the networked LaMnO3 NFs providing ORR/OER sites without severe aggregation, (2) the synergistic coupling of RuO2 NPs for further improving the OER activity and the electrical conductivity on the surface of the LaMnO3 NFs, and (3) the use of GNFs providing a fast electronic pathway as well as improved ORR kinetics. [ABSTRACT FROM AUTHOR]

Abstract: Lithium–oxygen (Li–O2) batteries are considered as the most promising candidates owing to their higher theoretical energy density than other energy storage devices. However, the unfavorable structure of the air cathode has become a major cause of low performance for Li–O2 batteries, limiting their use in practical applications. To deal with this issue, the rational construction of porous air electrodes, where crucial reactions take place, is in high demand. Among the various dimensional materials, 1D nanomaterials have been frequently applied for air electrodes in several different forms, owing to their fascinating morphologies and unique characteristics. We present a focus review on the recent research relating to 1D nanomaterials adopted as air electrodes in Li–O2 cells. This paper gives the current issues surrounding Li–O2 cells, which are analyzed in terms of the efforts to apply the advantages of 1D nanomaterial electrodes for enhancing the electrochemical performance of the given cells. [ABSTRACT FROM AUTHOR]

Patients receiving immunosuppression to prevent organ transplant rejection are at a greatly increased risk of developing nonmelanoma skin cancer. In recent years a correlation has been identified between the class of immunosuppressant that these patients receive and their subsequent cancer risk; in particular, patients switched from calcineurin inhibitors to mammalian target of rapamycin (mTOR) inhibitors not only displayed a dramatic reduction in new tumor formation but also in some cases a regression of their existing lesions. Studies of cancer models in mice and cell lines in the laboratory have attributed these discrepancies in cancer risk to the ability of immunosuppressants such as mTOR inhibitors to elicit direct anticancer effects, including suppressing angiogenesis and increasing autophagy-mediated DNA repair. Recent evidence from the immunological literature however, suggests a significant alternative contribution of mTOR inhibitors; namely the promotion of memory T-cell function. Recent advances in understanding memory T-cell establishment and the demonstration of their critical role in long-term immunity make it timely to review the available evidence as to whether the improved nonmelanoma skin cancer outcome shown by patients switched to mTOR inhibitor treatment regimens may be associated with the retainment of memory T-cell function. [ABSTRACT FROM AUTHOR]

ABSTRACT A simple, sensitive and reproducible isocratic reversed-phase (C18) high-performance liquid chromatography (HPLC) method was developed to determine 7- O-succinyl macrolactin A (SMA) in rat plasma and urine samples using UV detector set at 230 nm. Lamotrigine was used as internal standards (IS) to ensure the precision and accuracy of the method. The retention times of SMA and IS for the plasma sample were 9.2 and 4.4 min, respectively, and those for the urine samples were 7.9 and 4.3 min, respectively. The intra- and inter-day variations of the analytical responses, expressed in terms of relative standard deviation, were less than 14.9%. The accuracy, in terms of average analytical recovery, ranged from 90.4 to 119%. The lower limits of quantification of SMA in rat plasma and urine samples were 0.02 and 0.1 µg/mL, respectively. This method is applicable for the pharmacokinetic studies of SMA in rats. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Myelocytomatosis oncogene (c-MYC) is a well-known nuclear oncoprotein having multiple functions in cell proliferation, apoptosis and cellular transformation. Chromosomal modification is also important to the differentiation and growth of stem cells. Histone deacethylase (HDAC) and polycomb group (PcG) family genes are well-known chromosomal modification genes. The aim of this study was to elucidate the role of c-MYC in the expression of chromosomal modification via the HDAC family genes in human mesenchymal stem cells (hMSCs). To achieve this goal, c-MYC expression was modified by gene knockdown and overexpression via lentivirus vector. Using the modified c-MYC expression, our study was focused on cell proliferation, differentiation and cell cycle. Furthermore, the relationship of c-MYC with HDAC2 and PcG genes was also examined. The cell proliferation and differentiation were checked and shown to be dramatically decreased in c-MYC knocked-down human umbilical cord blood-derived MSCs, whereas they were increased in c-MYC overexpressing cells. Similarly, RT-PCR and Western blotting results revealed that HDAC2 expression was decreased in c-MYC knocked-down and increased in c-MYC overexpressing hMSCs. Database indicates presence of c-MYC binding motif in HDAC2 promoter region, which was confirmed by chromatin immunoprecipitation assay. The influence of c-MYC and HDAC2 on PcG expression was confirmed. This might indicate the regulatory role of c-MYC over HDAC2 and PcG genes. c-MYCs' regulatory role over HDAC2 was also confirmed in human adipose tissue-derived MSCs and bone-marrow derived MSCs. From this finding, it can be concluded that c-MYC plays a vital role in cell proliferation and differentiation via chromosomal modification. [ABSTRACT FROM AUTHOR]

Multiple lines of evidence indicate that inhibition of gap junction intercellular communication (GJIC) is a major carcinogenic process. Several reports suggest that activation of extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) plays a key role in the disrupted GJIC by hydrogen peroxide, 12-O-tetradecanoylphorbol-13-acetate, and quinones in rat liver epithelial cells. Recently, we reported that p38 mitogen-activated protein kinase (MAPK) is also involved in the inhibition of GJIC by hydrogen peroxide in WB-F344 rat liver epithelial cells (WB cells). The present study investigated the role of ERK1/2 and p38 MAPK in Hras-induced inhibition of GJIC in WB cells. Hras induces complete inhibition of GJIC and unphosphorylation of connexin 43 (Cx43) in WB cells. SB203580, an inhibitor of p38, restored inhibition of GJIC and blocked unphosphorylation of Cx43 in Hras-transformed WB cells. However, PD98059, an inhibitor of ERK1/2, had no effect. Our results suggest that the disruption of GJIC induced by Hras may be strongly related to the unphosphorylation of Cx43 via the activation of p38 but not ERK1/2. Thus, p38 is a key signaling molecule for Hras-induced inhibition of GJIC in WB cells. [ABSTRACT FROM AUTHOR]

The Cover picture shows an electric car powered by a Li–O2 battery driven on a road. The road is covered with graphene, which implies that the Li–O2 battery is supported by an air cathode catalyst composed of oxide nanofibers/nanoparticles attached onto graphene. The small yellow balls are RuO2 nanoparticles whereas the black wires are LaMnO3 nanofibers acting as efficient catalysts for discharging/charging battery. The big yellow balls represent lithium ions, red balls are oxygen molecules, and the gray rocks on the nanofibers are solid reaction products (Li2O2). More details can be found in the Full Paper by Yoon et al. on page 2080 in Issue 16, 2016 (DOI: 10.1002/cssc.201600341). [ABSTRACT FROM AUTHOR]