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A highly miniaturized monolithic microwave integrated circuit using common-emitter and common-collector circuits is fabricated for signal mixing. The active 90-degree power combiner's performance is superior to a passive combiner at S-band.

A highly integrated down-converter monolithic microwave integrated circuit using heterojunction bipolar transistors for Ku-band commercial wireless communication systems is designed. The circuit includes a mixer, a filter, an amplifier, and input/output matching circuits.

This paper propose a new algorithm to detect the intruder in room. The basic idea of the proposed method is to estimate the variation of features of the room acoustic transfer function(RTF). The room transfer function is computed by cross-correlation method. There are some methods to measure the RFT. For example there are the image methods, ray tracing method to measure actually the RFT. In this we estimated RTF using white Gaussian noise that is broadband signal. It is important to extract feature vectors. Feature extraction is the process of computing a numerical representation. We used various features to detect intruder. The features based on the Short Time Fourier Transform (STFT) and the zero-crossing rates were used. Several simulations and actually tests show that the proposed method provides good performance for intruder detection. Index Terms--intruder detection, feature, room transfer function, Short Time Fourier Transform

BACKGROUND:: Autologous fat grafting is one of the most common procedures used in plastic surgery to correct soft tissue deficiency or depression deformity. However, its clinical outcomes are often suboptimal, and lack of metabolic and architectural support at recipient sites affect fat survival leading to complications such as cyst formation, calcification. Extracellular matrix-based scaffolds, such as allograft adipose matrix (AAM) and poly(lactic-co-glycolic) acid (PLGA), have shown exceptional clinical promise as regenerative scaffolds. Magnesium hydroxide (MH), an alkaline ceramic, has attracted attention as a potential additive to improve biocompatibility. We attempted to combine fat graft with regenerative scaffolds and analyzed the changes and viability of injected fat graft in relation to the effects of injectable natural, and synthetic (PLGA/MH microsphere) biomaterials. METHODS:: In vitrocell cytotoxicity, angiogenesis of the scaffolds, and wound healing were evaluated using human dermal fibroblast cells. Subcutaneous soft-tissue integration of harvested fat tissue was investigated in vivoin nude mouse with random fat transfer protocol Fat integrity and angiogenesis were identified by qRT-PCR and immunohistochemistry. RESULTS:: In vitrocell cytotoxicity was not observed both in AAM and PLGA/MH with human dermal fibroblast. PLGA/MH and AAM showed excellent wound healing effect. In vivo, the AAM and PLGA/MH retained volume compared to that in the only fat group. And the PLGA/MH showed the highest angiogenesis and anti-inflammation. CONCLUSION:: In this study, a comparison of the volume retention effect and angiogenic ability between autologous fat grafting, injectable natural, and synthetic biomaterials will provide a reasonable basis for fat grafting.

This paper proposes a new extended decision-directed decision-estimated phase recovery algorithm based on maximum likelihood parameter estimation for OQPSK (Offset QPSK). In this scheme, comparing to conventional one, the data dependent noise of phase recovery loop is reduced by inserting the filter with 2 taps to inphase and quadrature channel respectively before the phase detector. Proposed scheme is compared to the conventional QPSK scheme in aspect to BER(Bit Error Rate) and phase error for roil-off factors of baseband filter, output backoffs of nonlinear satellite channel, and loop bandwidth.

Oxygen-based electrocatalysis is an integral aspect of a clean and sustainable energy conversion/storage system. The development of economic bifunctional electrocatalysts with high activity and durability during reversible reactions remains a great challenge. The tailored porous structure and separately presented active sites for oxygen reduction and oxygen evolution reactions (ORR and OER) without mutual interference are most crucial for achieving desired bifunctional catalysts. Here, we report a hybrid composed of sheath–core cobalt oxynitride (CoOx@CoNy) nanorods grown perpendicularly on N-doped carbon nanofiber (NCNF). The brush-like CoOx@CoNynanorods, composed of metallic Co4N cores and oxidized surfaces, exhibit excellent OER activity (E= 1.69 V at 10 mA cm–2) in an alkaline medium. Although pristine NCNF or CoOx@CoNyalone had poor catalytic activity in the ORR, the hybrid showed dramatically enhanced ORR performance (E= 0.78 V at −3 mA cm–2). The experimental results coupled with a density functional theory (DFT) simulation confirmed that the broad surface area of the CoOx@CoNynanorods with an oxidized skin layer boosts the catalytic OER, while the facile adsorption of ORR intermediates and a rapid interfacial charge transfer occur at the interface between the CoOx@CoNynanorods and the electrically conductive NCNF. Furthermore, it was found that the independent catalytic active sites in the CoOx@CoNy/NCNF catalyst are continuously regenerated and sustained without mutual interference during the round-trip ORR/OER, affording stable operation of Zn–air batteries.

Activation of AMP-activated protein kinase (AMPK), a physiological cellular energy sensor, strongly suppresses cell proliferation in both nonmalignant and tumor cells. This study demonstrates the mechanism of quercetin-induced apoptosis in HT-29 colon cancer cells. Treatment of cells with quercetin significantly decreased cell viability in a dose-dependent manner. Notably, quercetin increased cell cycle arrest in the G1 phase and up-regulated apoptosis-related proteins, such as AMPK, p53, and p21, within 48 h. Furthermore, in vivo experiments showed that quercetin treatment resulted in a significant reduction in tumor volume over 6 weeks, and apoptosis-related protein induction by quercetin was significantly higher in the 100 mg/kg treated group compared to the control group. All of these results indicate that quercetin induces apoptosis via AMPK activation and p53-dependent apoptotic cell death in HT-29 colon cancer cells and that it may be a potential chemopreventive or therapeutic agent against HT-29 colon cancer.

Lithium–oxygen batteries have been considered as one of the most viable energy source options for electric vehicles due to their high energy density. However, they are still faced with technical challenges, such as low round-trip efficiency and short cycle life, which mainly originate from the cathode part of the battery. In this work, we designed a three-dimensional nanofibrous air electrode consisted of hierarchically structured carbon nanotube-bridged hollow Fe2O3nanoparticles (H-Fe2O3/CNT NFs). Composite nanofibers consisted of hollow Fe2O3NPs anchored by multiple CNTs offered enhanced catalytic sites (interconnected hollow Fe2O3NPs) and fast charge-transport highway (bridged CNTs) for facile formation and decomposition of Li2O2, leading to outstanding cell performance: (1) Swagelok cell exhibited highly reversible cycling characteristics for 250 cycles with a fixed capacity of 1000 mAh g–1at a current density of 500 mA g–1. (2) A module composed of two pouch-type cells stably powered an light-emitting diode lamp operated at 5.0 V.

In accordance with the fourth industrial revolution (4IR), thin-film all-solid-state batteries (TF-ASSBs) are being revived as the most promising energy source to power small electronic devices. However, current TF-ASSBs still suffer from the perpetual necessity of high-performance battery components. While every component, a series of a TF solid electrolyte (i.e., lithium phosphorus oxynitride (LiPON)) and electrodes (cathode and Li metal anode), has been considered vital, the lack of understanding of and ability to ameliorate the cathode (or anode)–electrolyte interface (CEI) (or AEI) has impeded the development of TF-ASSBs. In this work, we suggest an ensemble design of TF-ASSBs using LiPON (500 nm), an amorphous TF-V2O5–xcathode with oxygen vacancies (Ovacancy), a thin evaporated Li anode (evp-Li) with a thickness of 1 μm, and an artificial ultrathin Al2O3layer between evp-Li and LiPON. Well-defined Ovacancysites, such as O(II)vacancyand O(III)vacancy, in amorphous TF-V2O5–xnot only allow isotropic Li+diffusion at the CEI but also enhance both the ionic and electronic conductivities. For the AEI, we employed protective Al2O3, which was specially sputtered using the facing target sputtering (FTS) method to form a homogeneous layer without damage from plasma. In regard to the contact with evp-Li, interfacial stability, electrochemical impedance, and battery performance, the nanometric Al2O3layers (1 nm) were optimized at different temperatures (40, 60, and 80 °C). The TF-ASSB cell containing Al2O3(1 nm) delivers a high specific capacity of 474.01 mAh cm–3under 60 °C at 2 C for the 400th cycle, and it achieves a long lifespan as well as ultrafast rate capability levels, even at 100 C; these results were comparable to those of TF Li-ion battery cells using a liquid electrolyte. We demonstrated the reaction mechanism at the AEI utilizing time-of-flight secondary ion mass spectrometry (TOF-SIMS) and molecular dynamics (MD) simulations for a better understanding. Our design provides a signpost for future research on the rational structure of TF-LIBs.

The fusion of different electroactive components of lithium-ion batteries (LIBs) sometimes brings exceptional electrochemical properties. We herein report the reduced graphene-oxide (rGO)-coated Zn2SnO4z@NiO nanofibers (ZSO@NiO@G NFs) formed by the synergistic fusion of three different electroactive components including ZnO, SnO2, and NiO that exhibit exceptional electrochemical properties as negative electrodes for LIBs. The simple synthetic route comprised of electrospinning and calcination processes enables to form porous one-dimensional (1D) structured ZSO, which is the atomic combination between ZnO and SnO2, exhibiting effective strain relaxation during battery operation. Furthermore, the catalytic effect of Ni converted from the surface-functional NiO nanolayer on ZSO significantly contributes to improved reversible capacity. Finally, rGO sheets formed on the surface of ZSO@NiO NFs enable to construct electrically conductive path as well as a stable SEI layer, resulting in excellent electrochemical performances. Especially, exceptional cycle lifespan of more than 1600 cycles with a high capacity (1060 mAh g–1) at a high current density (1000 mA g–1), which is the best result among mixed transition metal oxide (stannates, molybdates, cobaltates, ferrites, and manganates) negative electrodes for LIBs, is demonstrated.

It is evident that the exhaustive use of fossil fuels for decades has significantly contributed to global warming and environmental pollution. To mitigate the harm on the environment, lithium–oxygen batteries (LOBs) with a high theoretical energy density (3458 Wh kg–1Li2O2) compared to that of Li-ion batteries (LIBs) have been considered as an attractive alternative to fossil fuels. For this purpose, porous carbon materials have been utilized as promising air cathodes owing to their low cost, lightness, easy fabrication process, and high performance. However, the challenge thus far lies in the uncontrollable formation of Li2CO3at the interface between carbon and Li2O2, which is detrimental to the stable electrochemical performance of carbon-based cathodes in LOBs. In this work, we successfully protected the surface of the free-standing carbon nanofibers (CNFs) by coating it with a layer of iridium metal through direct sputtering (CNFs@Ir), which significantly improved the lifespan of LOBs. Moreover, the Ir would play a secondary role as an electrochemical catalyst. This all-in-one cathode was evaluated for the formation and decomposition of Li2O2during (dis)charging processes. Compared with bare CNFs, the CNFs@Ir cathode showed two times longer lifespan with 0.2 VLilower overpotentials for the oxygen evolution reaction. We quantitatively calculated the contents of CO32–in Li2CO3formed on the different surfaces of the bare CNFs (63% reduced) and the protected CNFs@Ir (78% reduced) cathodes after charging. The protective effects and the reaction mechanism were elucidated by ex situ analyses, including scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy.

Lithium–oxygen (Li–O2) batteries have been intensively investigated in recent decades for their utilization in electric vehicles. The intrinsic challenges arising from O2(electro)chemistry have been mitigated by developing various types of catalysts, porous electrode materials, and stable electrolyte solutions. At the next stage, we face the need to reform batteries by substituting pure O2gas with air from Earth’s atmosphere. Thus, the key emerging challenges of Li–air batteries, which are related to the selective filtration of O2gas from air and the suppression of undesired reactions with other constituents in air, such as N2, water vapor (H2O), and carbon dioxide (CO2), should be properly addressed. In this review, we discuss all key aspects for developing Li–air batteries that are optimized for operating in ambient air and highlight the crucial considerations and perspectives for future air-breathing batteries.

Despite a conventional belief that prosperity boosts presidential popularity, research on the effect of economic and political factors on presidential popularity shows wide variation. What are the main contributing factors when people evaluate their political leaders? How do economic conditions and perception of corruption influence people’s evaluations of their political leaders? Using comprehensive, up-to-date panel data covering 20 countries, mostly from Latin America, and also including South Korea and the United States, from 1988 to 2016, this study shows that the effect of gross domestic product (GDP) growth rate and unemployment rate are strong throughout the period considered. From the year 2000, inflation and perception of corruption become significant. In highly corrupt countries, however, the significance of corruption becomes more salient, together with GDP growth rate and unemployment rate, as citizens of these countries begin to evaluate their leaders in terms of their determination to address these problems. In countries with low approval ratings, voters generally weigh GDP growth rate more heavily.

Recently, gallium (Ga), one of the liquid metals (LMs), has been explored with special attention because of its liquid phase nature as a self-healing agent and Li storage characteristics. The current challenge that restricts the practical use of Ga is handling Ga easily without loss and understanding its reaction behavior in Li-ion batteries. One solution that helps to address the problem associated with liquid phases is to make solid phases such as gallium oxides and nitrides as starting materials for a stable conversion reaction. Here, we have successfully incorporated GaN nanoparticles into carbon confiners [1D carbon nanofibers (CNFs) with the outermost carbon coating layer] as an anode for the Li-ion battery. By preserving liquid Ga derived from GaN after the conversion reaction in conductive walls, long-term cycling performance (over 5000 cycles) is achievable. This work provides an insight into the LM-relevant materials/carbon composite in the area of the rechargeable battery.

The utilization of sustainable water electrolysis for hydrogen production is currently limited by sluggish kinetics of the oxygen evolution reaction (OER). The development of stable, highly active, and cost-effective OER catalyst supports would facilitate commercialization of water electrolysis technologies. In this study, we report for the first time the use of metallic cobalt nitride (Co4N) nanofibers (NFs) as highly stable and conductive scaffolds for supporting Ir nanoparticles (NPs). The Ir catalysts supported on Co4N NFs exhibit high OER activity and stability in alkaline media as compared with Ir catalysts supported on other materials (Co3O4or carbon NFs) and commercial Ir/C. These results are attributed to the (i) efficient charge or mass transport between Ir NPs and metallic one-dimensional (1D) Co4N NFs or interfibers, (ii) maintenance of the active oxidation state (Ir3+) of Ir NPs induced by synergistic charge compensation between catalyst and support during OER, and (iii) long-term stability induced by strong metal–support interactions.

Nanowires (NWs) synthesized viachemical vapor deposition (CVD) have demonstrated significant improvement in lithium storage performance along with their outstanding accommodation of large volume changes during the charge/discharge process. Nevertheless, NW electrodes have been confined to the research level due to the lack of scalability and severe side reactions by their high surface area. Here, we present nanoporous Ge nanofibers (NPGeNFs) having moderate nanoporosity viaa combination of simple electrospinning and a low-energetic zincothermic reduction reaction. In contrast with the CVD-assisted NW growth, our method provides high tunability of macro/microscopic morphologies such as a porosity, length, and diameter of the nanoscale 1D structures. Significantly, the customized NPGeNFs showed a highly suppressed volume expansion of less than 15% (for electrodes) after full lithation and excellent durability with high lithium storage performance over 500 cycles. Our approach offers effective 1D nanostructuring with highly customized geometries and can be extended to other applications including optoelectronics, catalysis, and energy conversion.

Facile synthesis of rationally designed nanostructured electrode materials with high reversible capacity is highly critical to meet ever-increasing demands for lithium-ion batteries. In this work, we employed defect engineering by incorporating metal organic framework (MOF) templates into one-dimensional nanostructures by simple electrospinning and subsequent calcination. The introduction of Co-based zeolite imidazole frameworks (ZIF-67) resulted in abundant oxygen vacancies, which induce not only more active sites for Li storage but also enhanced electrical conductivity. Moreover, abundant mesoporous sites are formed by the decomposition of ZIF-67, which are present both inside and outside the resultant SnO2–Co3O4nanofibers (NFs). Attributed to the creation of vacancy sites along with the synergistic effects of SnO2and Co3O4, SnO2–Co3O4NFs exhibit an excellent reversible capacity for 300 cycles (1287 mA h g–1at a current density of 500 mA g–1) along with superior rate capabilities and improved initial Coulombic efficiency compared with pristine SnO2NFs. This is an early report on utilizing MOF structures as the defect formation platform into one-dimensional nanostructures, which is expected to result in superior electrochemical performances required for advanced electrodes.

To date, lithium-oxygen batteries (LOBs) using porous carbon materials as the air cathode have been widely studied. However, a fundamental issue of carbon electrode still remains; the carbon surface is unstable and is highly reactive in contact with Li2O2, resulting in the formation of irreversible byproducts (e.g., Li2CO3). To address this issue, we investigated the use of surface protection layers for improving the cycling stability of porous carbon-based LOB cathode. We employed atomic layer deposition (ALD) for conformal coating of two types of overlayers (In2O3and TiN), i.e., oxide and nitride thin film, on an electrospun carbon nanopaper (CNp) membrane. The LOB cell with In2O3-coated CNp exhibited much enhanced cycling performance (over 140 cycles) compared with pristine CNp and TiN-coated CNp as control samples (less than 60 cycles for both cases). To further improve cell efficiency by reducing overpotentials, the surface of In2O3-coated CNp electrode was functionalized by catalytic RuOxnanoparticles, which enables stable and complete discharging and recharging reactions below 4.2 V for an extended period of 165 cycles. Interestingly, after each discharge, nanosheet-like Li2O2growth was observed on In2O3-coated CNps, which is advantageous for enhanced cycle life. This work demonstrates that use of a free-standing, high surface area carbon membrane, that is conformally encapsulated by a highly conductive and stable oxide protection layer, is essential for enhanced Li-O2cell performance by preventing direct contact between underneath carbon and electrolyte.

PURPOSE:To investigate the long-term clinical outcomes and recurrence patterns of phototherapeutic keratectomy (PTK) in patients with granular corneal dystrophy type 2 (GCD2) exacerbated after LASIK.METHODS:Fifty-one patients (76 eyes) with GCD2 exacerbated after LASIK who underwent PTK between January 2007 and February 2017 were included. Participants underwent ophthalmic examination, including slit-lamp microscopy, corrected distance visual acuity (CDVA), slit-lamp photography, and Fourier domain optical coherence tomography at preoperative and postoperative visits. PTK was performed using VISX S4 IR (VISX, Inc., Santa Clara, CA). Visual acuity, complications, interval, and contributing factors of recurrence were evaluated.RESULTS:The follow-up period ranged from 1 to 108 months (mean: 35.22 months). The mean logMAR CDVA was 0.55 ± 0.43 (Snellen equivalent 20/80) preoperatively and 0.09 ± 0.43 (Snellen equivalent 20/25) at 3 months postoperatively. Forty-five (61.6%) eyes developed biomicroscopic recurrence at a mean of 18.6 months after PTK; 20 (27.4%) eyes developed significant recurrence at a mean of 31.3 months after PTK. The flap removal group demonstrated better CDVA at 3 years after surgery and lower recurrence and complication rates than the flap conservation group. Multivariate analysis revealed that flap removal remarkably reduced the risk of both any sign of and significant recurrence.CONCLUSIONS:PTK improved corneal transparency and visual acuity in patients with GCD2 exacerbated after LASIK, although GCD2 eventually recurred. PTK with flap removal was superior to PTK with flap conservation in terms of visual acuity, recurrence, and complications.[[J Refract Surg.2018;34(2):132–139.]

To achieve a high reversibility and long cycle life for lithium–oxygen (Li–O2) batteries, the irreversible formation of Li2O2, inevitable side reactions, and poor charge transport at the cathode interfaces should be overcome. Here, we report a rational design of air cathode using a cobalt nitride (Co4N) functionalized carbon nanofiber (CNF) membrane as current collector-catalyst integrated air cathode. Brush-like Co4N nanorods are uniformly anchored on conductive electrospun CNF papers via hydrothermal growth of Co(OH)F nanorods followed by nitridation step. Co4N-decorated CNF (Co4N/CNF) cathode exhibited excellent electrochemical performance with outstanding stability for over 177 cycles in Li–O2cells. During cycling, metallic Co4N nanorods provide sufficient accessible reaction sites as well as facile electron transport pathway throughout the continuously networked CNF. Furthermore, thin oxide layer (<10 nm) formed on the surface of Co4N nanorods promote reversible formation/decomposition of film-type Li2O2, leading to significant reduction in overpotential gap (∼1.23 V at 700 mAh g–1). Moreover, pouch-type Li-air cells using Co4N/CNF cathode stably operated in real air atmosphere even under 180° bending. The results demonstrate that the favorable formation/decomposition of reaction products and mediation of side reactions are hugely governed by the suitable surface chemistry and tailored structure of cathode materials, which are essential for real Li–air battery applications.

The combination of high-capacity and long-term cyclability has always been regarded as the first priority for next generation anode materials in lithium-ion batteries (LIBs). To meet these requirements, the Ag nanoparticle decorated mesoporous SnO2/NiO nanotube (m-SNT) anodes were synthesized viaan electrospinning process, followed by fast ramping rate calcination and subsequent chemical reduction in this work. The one-dimensional porous hollow structure effectively alleviates a large volume expansion during cycling as well as provides a short lithium-ion duffusion length. Furthermore, metallic nickel (Ni) nanoparticles converted from the NiO nanograins during the lithiation process reversibly decompose Li2O during delithiation process, which significantly improves the reversible capacity of the m-SNT anodes. In addition, Ag nanoparticles uniformly decorated on the m-SNT viaa simple chemical reduction process significantly improve rate capability and also contribute to long-term cyclability. The m-SNT@Ag anodes exhibited excellent cycling stability without obvious capacity fading after 500 cycles with a high capacity of 826 mAh g–1at a high current density of 1000 mA g–1. Furthermore, even at a very high current density of 5000 mA g–1, the charge-specific capacity remained as high as 721 mAh g–1, corresponding to 60% of its initial capacity at a current density of 100 mA g–1.

Controlling structural and morphological features of molybdenum disulfide (MoS2) nanoplates determines anode reaction performance for Li-ion and Na-ion batteries. In this work, we investigate dimensional effects of MoS2nanoplates randomly embedded in twisted mesoporous carbon nanofibers (MoS2@MCNFs) on Li and Na storage properties. Considering dimensions of the MoS2nanoplates (e.g., interlayer, lateral distance, and slabs of stacking in number), we controlled thermolysis temperature to synthesize the MoS2nanoplates with different geometry and optimize them in the hybrid anode for delivering high performance. The MoS2@MCNFs electrode exhibits reversible Li and Na capacities greater than 1000 cycles even at high current density of 1.0 A g–1(1221.94 mAh g–1with capacity retention of 95.6% for Li-ion batteries and 447.29 mAh g–1with capacity retention of 87.11% for Na-ion batteries). We elucidated the insertion, conversion, and interfacial reaction characteristics of the thermosensitive MoS2nanoplates in the MCNFs, especially associated with a reversible capacity. Our study will hint at rational design of the nanostructured MoS2electrodes and focus on significance of their dimensional effects on anode performance.

We investigated changes in visual function after wearing decorative tinted soft contact lenses with different pigment-free optical zone diameters.

To exploit the benefits of nanostructuring for enhanced hydrogen evolution reaction (HER), we employed coaxial electrospinning to synthesize single-layered WS2nanoplates anchored to hollow nitrogen-doped carbon nanofibers (WS2@HNCNFs) as efficient electrocatalysts. For comparison, bulk WS2powder and single layers of WS2embedded in nitrogen-doped carbon nanofibers (WS2@NCNFs) were synthesized and electrochemically tested. The distinctive design of the WS2@HNCNFs enables remarkable electrochemical performances showing a low overpotential with reduced charge transfer resistance, a small Tafel slope, and excellent durability. The experimental results highlight the importance of nanostructure engineering in electrocatalysts for enhanced HER.

Amorphous silicon (a-Si) has been intensively explored as one of the most attractive candidates for high-capacity and long-cycle-life anode in Li-ion batteries (LIBs) primarily because of its reduced volume expansion characteristic (∼280%) compared to crystalline Si anodes (∼400%) after full Li+insertion. Here, we report one-dimensional (1-D) electrospun Si-based metallic glass alloy nanofibers (NFs) with an optimized composition of Si60Sn12Ce18Fe5Al3Ti2. On the basis of careful compositional tailoring of Si alloy NFs, we found that Ce plays the most important role as a glass former in the formation of the metallic glass alloy. Moreover, Si-based metallic glass alloy NFs were wrapped by reduced graphene oxide sheets (specifically Si60Sn12Ce18Fe5Al3Ti2NFs@rGO), which can prevent the direct exposure of a-Si alloy NFs to the liquid electrolyte and stabilize the solid-electrolyte interphase (SEI) layers on the surfaces of rGO sheets while facilitating electron transport. The metallic glass nanofibers exhibited superior electrochemical cell performance as an anode: (i) Si60Sn12Ce18Fe5Al3Ti2NFs show a high specific capacity of 1017 mAh g–1up to 400 cycles at 0.05C with negligible capacity loss as well as superior cycling performance (nearly 99.9% capacity retention even after 2000 cycles at 0.5C); (ii) Si60Sn12Ce18Fe5Al3Ti2NFs@rGO reveals outstanding rate behavior (569.77 mAh g–1after 2000 cycles at 0.5C and a reversible capacity of around 370 mAh g–1at 4C). We demonstrate the potential suitability of multicomponent a-Si alloy NFs as a long-cycling anode material.

PURPOSE:To compare the measurements of refractive errors and ocular aberrations obtained using iDesign and WaveScan (Abbott Medical Optics, Inc., Santa Ana, CA), and to compare surgical outcomes of wavefront-guided LASEK using ablation profiles based on both aberrometers.METHODS:Ninety myopic eyes of 45 normal patients were evaluated using both the iDesign and WaveScan to measure spherical and cylindrical errors, spherical equivalents, and Zernike coefficients of ocular aberrations. Wavefront-guided LASEK was performed in a different group of 59 eyes of 30 patients divided into two groups, the iDesign and Wavescan groups. The clinical outcomes between the two groups including uncorrected visual acuity, refractive errors, contrast sensitivity, and ocular aberration were compared at 1, 3, and 6 months postoperatively.RESULTS:The iDesign produced significantly higher myopic values for refractive errors than the WaveScan, as well as significantly lower levels of total higher order, third, fourth, and fifth order root mean square values and Zernike coefficients of vertical coma and spherical aberration. At postoperative 1, 3, and 6 months, there were no statistically significant differences between the two groups in terms of uncorrected visual acuity and remaining refractive errors. The percentages of patients with spherical equivalents within ±1.00 and ±0.50 diopters of emmetropia were 100% (29 eyes) and 75.9% (22 eyes), respectively, in the iDesign group and 96.7% (29 eyes) and 70.0% (21 eyes), respectively, in the WaveScan group. Mesopic contrast sensitivity values were significantly higher, and the change in root mean square values for spherical aberration was significantly lower in the iDesign group.CONCLUSIONS:There were significant differences between the iDesign and the WaveScan in the measurements of refraction and ocular aberrations. Wavefront-guided LASEK based on an ablation profile from the iDesign demonstrated comparable refractive predictability with the WaveScan group, resulting in minimal physician adjustment and superior postoperative visual quality.[[J Refract Surg.2015;31(6):398–405.]

The aim of this study was to investigate long-term clinical outcomes of conjunctival flap surgery for calcified scleromalacia after periocular surgery.

Review of how CD4/CD8 double‐positive T cells are transcriptionally regulated and impacted by age, species, and specific disease setting. CD4+/CD8+DP thymocytes are a well‐described T cell developmental stage within the thymus. However, once differentiated, the CD4+lineage or the CD8+lineage is generally considered to be fixed. Nevertheless, mature CD4+/CD8+DP T cells have been described in the blood and peripheral lymphoid tissues of numerous species, as well as in numerous disease settings, including cancer. The expression of CD4 and CD8 is regulated by a very strict transcriptional program involving the transcription factors Runx3 and ThPOK. Initially thought to be mutually exclusive within CD4+and CD8+T cells, CD4+/CD8+T cell populations, outside of the thymus, have recently been described to express concurrently ThPOK and Runx3. Considerable heterogeneity exists within the CD4+/CD8+DP T cell pool, and the function of CD4+/CD8+T cell populations remains controversial, with conflicting reports describing cytotoxic or suppressive roles for these cells. In this review, we describe how transcriptional regulation, lineage of origin, heterogeneity of CD4 and CD8 expression, age, species, and specific disease settings influence the functionality of this rarely studied T cell population.

Data sharing is an essential element of research; however, recent scientific and social developments have challenged conventional methods for protecting privacy. Here we provide guidance for determining data sharing thresholds for human pluripotent stem cell research aimed at a wide range of stakeholders, including research consortia, biorepositories, policy-makers, and funders.

CD49f (integrin subunit α6) regulates signaling pathways in a variety of cellular activities. However, the role of CD49f in regulating the differentiation and pluripotency of stem cells has not been fully investigated. Therefore, in this study, human mesenchymal stem cells (hMSCs) were induced to form spheres under nonadherent culture conditions, and we found that the CD49f‐positive population was enriched in MSC spheres compared with MSCs in a monolayer. The expression of CD49f regulated the ability of hMSCs to form spheres and was associated with an activation of the phosphatidylinositol 3‐kinase (PI3K)/AKT signaling pathway. Furthermore, the forced expression of CD49f modulated the proliferation and differentiation potentials of hMSCs through prolonged activation of PI3K/AKT and suppressed the level of p53. We showed that the pluripotency factors OCT4 and SOX2 were recruited to the putative promoter region of CD49f, indicating that OCT4 and SOX2 play positive roles in the expression of CD49f. Indeed, CD49f expression was upregulated in human embryonic stem cells (hESCs) compared with hMSCs. The elevated level of CD49f expression was significantly decreased upon embryoid body formation in hESCs. In hESCs, the knockdown of CD49f downregulated PI3K/AKT signaling and upregulated the level of p53, inducing differentiation into three germ layers. Taken together, our data suggest that the cell‐surface protein CD49f has novel and dynamic roles in regulating the differentiation potential of hMSCs and maintaining pluripotency. STEMCELLS2012;30:876–887

Niemann Pick disease type C1 (NPC) is an autosomal recessive disease characterized by progressive neurological deterioration leading to premature death. In this study, we hypothesized that human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) have the multifunctional abilities to ameliorate NPC symptoms in the brain. To test this hypothesis, hUCB-MSCs were transplanted into the hippocampus of NPC mice in the early asymptomatic stage. This transplantation resulted in the recovery of motor function in the Rota Rod test and impaired cholesterol homeostasis leading to increased levels of cholesterol efflux-related genes such as LXRα, ABCA1, and ABCG5 while decreased levels of 3-hydroxy-3-methylglutaryl coenzyme A reductase were observed in NPC mice. In the cerebrum, hUCB-MSCs enhanced neuronal cell survival and proliferation, where they directly differentiated into electrically active MAP2-positive neurons as demonstrated by whole-cell patch clamping. In addition, we observed that hUCB-MSCs reduced Purkinje neuronal loss by suppression of inflammatory and apoptotic signaling in the cerebellum as shown by immunohistochemistry. We further investigated how hUCB-MSCs enhance cellular survival and inhibit apoptosis in NPC mice. Neuronal cell survival was associated with increased PI3K/AKT and JAK2/STAT3 signaling; moreover, hUCB-MSCs modulated the levels of GABA/glutamate transporters such as GAT1, EAAT2, EAAT3, and GAD6 in NPC mice as assessed by Western blot analysis. Taken together, our findings suggest that hUCB-MSCs might play multifunctional roles in neuronal cell survival and ameliorating motor deficits of NPC mice.

Eight compounds (1−8) were isolated from a methanol extract of Cibotium barometzrhizomes including two new furan derivatives, cibotiumbarosides A (1) and B (2), and a new glycoglycerolipid, cibotiglycerol (4). Their structures were elucidated by chemical and spectroscopic methods. Compounds 2−5each showed inhibition of osteoclast formation with no affect on BMM cell viability.

The two distinct members of the mitogen-activated protein (MAP) kinase family c-Jun N-terminal protein kinase (JNK) and p38 MAP kinase, play an important role in central nervous system (CNS) development and differentiation. However, their role and functions are not completely understood in CNS. To facilitate in vitro study, we have established an immortal stem cell line using SV40 from fetal rat embryonic day 17. In these cells, MAP kinase inhibitors (SP600125, SB202190, and PD98059) were treated for 1, 24, 48, and 72h to examine the roles of protein kinases. Early inhibition of JNK did not alter phenotypic or morphological changes of immortalized cells, however overexpression of Bax and decrease of phosphorylated AKT was observed. The prolonged inhibition of JNK induced polyploidization of immortalized cells, and resulted in differentiation and inhibition of cell proliferation. Moreover, JNK and p38 MAP kinase but not ERK1/2 was activated, and p21, p53, and Bax were overexpressed by prolonged inhibition of JNK.

Sodium butyrate (NaBu) has an inhibitory effect on histone deacetylases (HDACs). The mitogen-activated protein (MAP) kinases, such as extracellular signal-regulated kinase 1/2 (ERK1/2) and p38 MAP, kinase are known to be modulated during NaBu-induced apoptosis. In the present study, we showed that low concentrations of NaBu could induce apoptosis synergistically with the inhibition of p38 MAP kinase as proven by using specific p38 MAP kinase inhibitor and dominant negative p38 transfection in a ras-transformed rat liver epithelial cell line (WB-ras). There were no changes in HDAC1, suggesting that NaBu might be able to kill transformed cells bypassing the HDAC inhibitory effect. We further demonstrated that inhibition of p38 MAP kinase potentiated apoptotic cascades, including cleavage of poly(ADP-ribose) polymerase, caspase-3, and decrease in Bcl-2/Bax ratio even at a lower concentration of NaBu. Thus, p38 MAP kinase played inhibitory roles in NaBu-induced apoptosis, and simultaneous modulation of MAP kinases in NaBu treatment could increase the efficiency of the chemotherapeutic effect of NaBu.Antioxid. Redox Signal. 7, 1767–1772.

The objective of this study is to obtain detailed information for the micro fabrication of lead frames by applying spray technology to wet etching process. Wet etching experiments were performed with different etching parameters such as injection pressure, distance from nozzle tip to etched substrate, nozzle pitch and etchant temperature. The characteristics of single and twin spray were measured to investigate the correlation between the spray characteristics and the etching characteristics. Drop size and velocity were measured by Phase-Doppler Anemometer (PDA). Four liquids of different viscosity were used to reveal the effects of viscosity on the spray characteristics. The results indicated that the shorter the distance from nozzle tip and the nozzle pitch, the larger etching factor became. The average etching factor had good positive correlation with average axial velocity and impact force. It was found that the etching characteristics depended strongly on the spray characteristics.

Flexible lithium–air batteries (F-LABs) operating under ambient air have attracted much interest as small-sized energy storage devices in routine household settings. Although the instability of the commonly used carbon cathode has prompted the search for a carbon-free cathode, there has not been much success in their development thus far. Here, we report a novel strategic approach to fabricate a large-area carbon-free cathode for shape-deformable F-LABs in ambient air. An electronically conductive and catalytic layer consisting of metallic iridium (Ir) and outermost IrOxwas deposited on porous, flexible polyimide nanofibers (PI@IrOxNFs) by radio frequency (RF) sputtering, which was employed as the flexible cathode. Their properties were evaluated under dynamic deformation modes such as bending, folding, twisting, and crumpling. The F-LAB cells with PI@IrOxNFs were stable for 150 cycles using pure O2, and in a dry-air atmosphere (O2/CO2/N2), they remain stable for 300 cycles (=600 h) with low discharge/charge overpotentials by the redox mediator and solid-state electrolyte (L1.3Al0.3Ti1.7(PO4)3, LATP). We elucidate the reaction mechanism at the IrOxsurface using ex-situ analyses and density functional theory (DFT) calculations. When applied to pouch-/cable-type F-LAB cells using two different electrolytes (gel-polymer and poly(ethylene oxide)(PEO)/LATP composite electrolytes), the PI@IrOxNFs show superior electrochemical characteristics during repetitive 300 bending cycles for over 60 h in ambient air. Furthermore, the F-LAB cells could be assembled using 3D-printed shape-deformable polyurethane (PU) as the packaging material, demonstrating their practical operation in small devices for the first time.

ABSTRACTPatients receiving immunosuppressive drugs to prevent organ transplant rejection exhibit a greatly increased risk of developing cutaneous squamous cell carcinoma (SCC). However, not all immunosuppressive drugs confer the same risk. Randomised, controlled trials demonstrate that switching renal transplant recipients receiving calcineurin inhibitor-based therapies to mammalian target of rapamycin (mTOR) inhibitors results in a reduced incidence of de novoSSC formation, and can even result in the regression of pre-existing premalignant lesions. However, the contribution played by residual immune function in this setting is unclear. We examined the hypotheses that mTOR inhibitors promote the enhanced differentiation and function of CD8+memory T cells in the skin. Here, we demonstrate that the long-term oral administration of rapamycin to achieve clinically-relevant whole blood drug target thresholds, creates a “low rapamycin dose” environment in the skin. While both rapamycin and the calcineurin inhibitor tacrolimus elongated the survival of OVA-expressing skin grafts, and inhibited short-term antigen-specific CD8+T cell responses, rapamycin but not tacrolimus permitted the statistically significant infiltration of CD8+effector memory T cells into UV-induced SCC lesions. Furthermore, rapamycin uniquely enhanced the number and function of CD8+effector and central memory T cells in a model of long-term contact hypersensitivity provided that rapamycin was present during the antigen sensitization phase. Thus, our findings suggest that patients switched to mTOR inhibitor regimens likely experience enhanced CD8+memory T cell function to new antigen-challenges in their skin, which could contribute to their lower risk of de novoSSC formation and regression of pre-existing premalignant lesions.

Although there are a number of weaknesses for clinical use, pluripotent stem cells are valuable sources for patient-specific cell therapies against various diseases. Backed-up by a huge number of basic researches, neuronal differentiation mechanism is well established and pluripotent stem cell therapies against neurological disorders are getting closer to clinical application. However, there are increasing needs for standardization of the sourcing pluripotent stem cells by establishing stem cell registries and banking. Global harmonization will accelerate practical use of personalized therapies using pluripotent stem cells.