50 research outputs found

    Lithography-Free Route to Hierarchical Structuring of High-chi Block Copolymers on a Gradient Patterned Surface

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    A chemically defined patterned surface was created via a combined process of controlled evaporative self-assembly of concentric polymer stripes and the selective surface modification of polymer brush. The former process involved physical adsorption of poly (methyl methacrylate) (PMMA) segments into silicon oxide surface, thus forming ultrathin PMMA stripes, whereas the latter process was based on the brush treatment of silicon native oxide surface using a hydroxyl-terminated polystyrene (PS-OH). The resulting alternating PMMA- and PS-rich stripes provided energetically favorable regions for self-assembly of high <mml:semantics>chi</mml:semantics> polystyrene-block-polydimethylsiloxane (PS-b-PDMS) in a simple and facile manner, dispensing the need for conventional lithography techniques. Subsequently, deep reactive ion etching and oxygen plasma treatment enabled the transition of the PDMS blocks into oxidized groove-shaped nanostructures

    Combined effects of aerobic exercise and 40-Hz light flicker exposure on early cognitive impairments in Alzheimerā€™s disease of 3ƗTg mice

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    Alzheimerā€™s disease (AD) is a progressive degenerative brain disease and the primary cause of dementia. At an early stage, AD is generally characterized by short-term memory impairment, owing to dysfunctions of the cortex and hippocampus. We previously reported that a combination of exercise and 40-Hz light flickering can protect against AD-related neuroinflammation, gamma oscillations, reduction in AĪ², and cognitive decline. Therefore, we sought to extend our previous findings to the 5-mo-old 3ƗTg-AD mouse model to examine whether the same favorable effects occur in earlier stages of cognitive dysfunction. We investigated the effects of 12 wk of exercise combined with 40-Hz light flickering on cognitive function by analyzing neuroinflammation, mitochondrial function, and neuroplasticity in the hippocampus in a 3ƗTg-AD mouse model. Five-month-old 3ƗTg-AD mice performed 12 wk of exercise with 40-Hz light flickering administered independently and in combination. Spatial learning and memory, long-term memory, hippocampal AĪ², tau, neuroinflammation, proinflammatory cytokine expression, mitochondrial function, and neuroplasticity were analyzed. AĪ² and tau proteins levels were significantly reduced in the early stage of AD, resulting in protection against cognitive decline by reducing neuroinflammation and proinflammatory cytokines. Furthermore, mitochondrial function improved, apoptosis was reduced, and synapse-related protein expression increased. Overall, exercise with 40-Hz light flickering was significantly more effective than exercise or 40-Hz light flickering alone, and the improvement was comparable to the levels in the nontransgenic aged-match control group. Our results indicate a synergistic effect of exercise and 40-Hz light flickering on pathological improvements in the hippocampus during early AD-associated cognitive impairment

    Avian influenza virus transmission is suppressed in chickens fed Lactobacillus paracasei expressing the 3D8 single-chain variable fragment protein

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    The 3D8 single-chain variable fragment (scFv) is a mini-antibody sequence with independent nuclease activity that shows antiviral effects against all types of viruses in chickens and mice. In this study, chickens were treated daily with an oral dose of 109 CFU Lactobacillus paracasei (L. paracasei) expressing either a secreted or anchored 3D8 scFv for three weeks. After L. paracasei administration, the chickens were challenged with avian influenza virus (AIV). From each experimental group, three chickens were directly infected with 100 ĀµL of 107.5 EID50/mL H9N2 AIV and seven chickens were indirectly challenged through contact transmission. oropharyngeal and cloacal swab samples were collected at 3, 5, 7, and 9 days post-inoculation (dpi) from AIV-challenged chickens, AIV Shedding titres were measured by quantitative real-time PCR. Contact transmission in the chickens that were fed 3D8 scFv-secreting L. paracasei showed a significant reduction in viral shedding when compared with other groups. These results suggest that L. paracasei secreting 3D8 provides a basis for the development of ingestible antiviral probiotics with activity against AIV

    Elevated red cell distribution width is associated with advanced fibrosis in NAFLD

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    Background/AimsThe red-blood-cell distribution width (RDW) is a newly recognized risk marker in patients with cardiovascular disease, but its role in nonalcoholic fatty liver disease (NAFLD) has not been well defined. The aim of the present study was to determine the association between RDW values and the level of fibrosis in NAFLD according to BARD and FIB-4 scores.MethodsThis study included 24,547 subjects who had been diagnosed with NAFLD based on abdominal ultrasonography and questionnaires about alcohol consumption. The degree of liver fibrosis was determined according to BARD and FIB-4 scores. The association between RDW values and the degree of fibrosis in NAFLD was analyzed retrospectively.ResultsAfter adjusting for age, hemoglobin level, mean corpuscular volume, history of hypertension, history of diabetes, and high-sensitivity C-reactive protein, the RDW values were 12.61Ā±0.41% (meanĀ±SD), 12.70Ā±0.70%, 12.77Ā±0.62%, 12.87Ā±0.82%, and 13.25Ā±0.90% for those with BARD scores of 0, 1, 2, 3, and 4, respectively, and 12.71Ā±0.72%, 12.79Ā±0.66%, and 13.23Ā±1.52% for those with FIB-4 scores of <1.30, 1.31-2.66, and ā‰„2.67, respectively (P<0.05). The prevalence of advanced fibrosis (BARD score of 24 and FIB-4 score of ā‰„1.3) increased with the RDW [BARD score: 51.1% in quartile 1 (Q1) vs. 63.6% in Q4; FIB-4 score: 6.9% in Q1 vs. 10.5% in Q4; P<0.001]. After adjustments, the odds ratio of having advanced fibrosis for those in Q4 compared to Q1 were 1.76 (95%CI=1.55-2.00, P<0.001) relative to BARD score and 1.69 (95%CI=1.52-1.98, P<0.001) relative to FIB-4 score.ConclusionsElevated RDW is independently associated with advanced fibrosis in NAFLD

    Fast and slow propagations of surface plasmon polaritons on metallic mesh gratings

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    Ā© 2018 IOP Publishing Ltd. Surface plasmon polariton (SPP) generations on silver-based metal-insulator-metal (MIM) cross mesh gratings were studied by polychromatic and monochromatic specular reflection. Centimeter area scale mesh grating samples were made using soft-lithography imprinting with a varied micro-sized array pitch. The mesh structures support multiple SPP orders with a periodicity-influenced mode generation. For the (Ā±1, 0) SPP modes steep dispersions thus high SPP group velocities Vg were obtained over an extended wavelength range of propagation. Vg were found to achieve a maximum at frequencies closer to the mesh periodicity

    Formation of Li2CO3 Nanostructures for Lithium-Ion Battery Anode Application by Nanotransfer Printing

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    Various high-performance anode and cathode materials, such as lithium carbonate, lithium titanate, cobalt oxides, silicon, graphite, germanium, and tin, have been widely investigated in an effort to enhance the energy density storage properties of lithium-ion batteries (LIBs). However, the structural manipulation of anode materials to improve the battery performance remains a challenging issue. In LIBs, optimization of the anode material is a key technology affecting not only the power density but also the lifetime of the device. Here, we introduce a novel method by which to obtain nanostructures for LIB anode application on various surfaces via nanotransfer printing (nTP) process. We used a spark plasma sintering (SPS) process to fabricate a sputter target made of Li2CO3, which is used as an anode material for LIBs. Using the nTP process, various Li2CO3 nanoscale patterns, such as line, wave, and dot patterns on a SiO2/Si substrate, were successfully obtained. Furthermore, we show highly ordered Li2CO3 nanostructures on a variety of substrates, such as Al, Al2O3, flexible PET, and 2-Hydroxylethyl Methacrylate (HEMA) contact lens substrates. It is expected that the approach demonstrated here can provide new pathway to generate many other designable structures of various LIB anode materials

    Formation of Li2 Co3 nanostructures for Lithium-ion battery anode application by nanotransfer printing

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    Various high-performance anode and cathode materials, such as lithium carbonate, lithium titanate, cobalt oxides, silicon, graphite, germanium, and tin, have been widely investigated in an effort to enhance the energy density storage properties of lithium-ion batteries (LIBs). However, the structural manipulation of anode materials to improve the battery performance remains a challenging issue. In LIBs, optimization of the anode material is a key technology affecting not only the power density but also the lifetime of the device. Here, we introduce a novel method by which to obtain nanostructures for LIB anode application on various surfaces via nanotransfer printing (nTP) process. We used a spark plasma sintering (SPS) process to fabricate a sputter target made of Li2 CO3, which is used as an anode material for LIBs. Using the nTP process, various Li2 CO3 nanoscale patterns, such as line, wave, and dot patterns on a SiO2 /Si substrate, were successfully obtained. Furthermore, we show highly ordered Li2 CO3 nanostructures on a variety of substrates, such as Al, Al2 O3, flexible PET, and 2-Hydroxylethyl Methacrylate (HEMA) contact lens substrates. It is expected that the approach demonstrated here can provide new pathway to generate many other designable structures of various LIB anode materials. Ā© 2021 by the authors. Licensee MDPI, Basel, Switzerland.N

    Ultra-rapid pattern formation of block copolymers with a high-chi parameter in immersion annealing induced by a homopolymer

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    The directed self-assembly (DSA) of block copolymers (BCPs) has attracted considerable attention due to the outstanding ability of this method to complement or replace the conventional photolithography process. However, there are critical issues to resolve in order to realize the rapid pattern formation of BCPs with a high Flory-Huggins parameter (chi). Here, we introduce a simple method to expedite the self-assembly kinetics with the addition of a polystyrene homopolymer (hPS) to poly(styrene-b-dimethylsiloxane) (PS-b-PDMS) BCPs with a high-chi parameter. We provide a systematic presentation of how the hPS affects the self-assembly of PS-b-PDMS BCPs in the immersion annealing process. We found the optimum annealing conditions of the mixing ratio for the hPS/PS-b-PDMS BCP blends, showing a very short annealing time (&lt;1 min) to obtain highly-ordered nanostructures. In addition, we discuss how the annealing temperature and mixing ratio of the binary solvent improve the self-assembly kinetics of the hPS/PS-b-PDMS BCP blends, suggesting a new route which effectively enhances the self-assembly speed. We believe that this facile and useful approach is applicable to the other BCP combination studies, contributing to the development of the next-generation BCP lithographyclose
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