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Here, we report the synthesis of three-dimensional (3D) polycaprolactone (PCL) nanofiber incorporated with core-satellite platinum nanoparticles (PtNPs, 2–3 nm) coated gold nanospheres (AuNPs, 30 nm) via the simple lactic acid assisted self-assembly electrospinning technique. The Pt-AuNPs nanoparticle in core-satellite form has been prepared by following solution based methods and characterized with TEM, HR-TEM, UV-Visible, and XRD spectroscopic techniques. The surface morphology and structural analysis of 3D nanofiber scaffolds have been performed with FTIR, TGA, FESEM, and HR-TEM analysis techniques and shown the successful preparation of 3D electrospun fibrous structure composed of Pt-AuNPs loaded PCL (PCL@Pt-AuNPs) as a potential biomaterial for bone tissue engineering applications.

A bioinspired three-dimensional (3D) fibrous structure possesses biomimicry, valuable functionality, and performance to scaffolding in tissue engineering. In particular, an electrospun fibrous mesh has been studied as a scaffold material in various tissue regeneration applications. We produced a low-density 3D polycaprolactone/lactic acid (LA) fibrous mesh (3D-PCLS) via the novel lactic-assisted 3D electrospinning technique exploiting the catalytic properties of LA as we reported previously. In the study, we demonstrated a strategy of recycling the LA component to synthesize the osteoinductive biomolecules in situ, calcium lactate (CaL), thereby forming a 3D bioactive PCL/CaL fibrous scaffold (3D-SCaL) for bone tissue engineering. The fiber morphology of 3D-PCLS and its packing degree could have been tailored by modifying the spinning solution and the collector design. 3D-SCaL demonstrated successful conversion of CaL from LA and exhibited the significantly enhanced biomineralization capacity, cell infiltration and proliferation rate, and osteoblastic differentiation in vitro with two different cell lines, MC3T3-e1 and bone marrow stem cells. In conclusion, 3D-SCaL proves to be a highly practical and accessible strategy using a variety of polymers to produce 3D fibers as a potential candidate for future regenerative medicine and tissue engineering applications.

Solution-based thin-film solidification is a complex process involving various transport phenomena that are intricately dependent on multiple experimental parameters. The difficulty of analyzing this process experimentally or conducting exact numerical simulation make it challenging to understand, predict, and control the solidification process. In this work, a simple and effective technique to analyze the thin-film solidification process during solution shearing, based on 3D geometrical model of the meniscus, is proposed. The 3D meniscus geometry, which changes depending on the experimental parameters, is attained using high-speed side-view and top-view in situ microscopy. Thereafter, mass and momentum transport mathematical models are applied to obtain numerical solutions of transport phenomena within the meniscus. Utilizing these results, the underlying mechanism of dendritic growth of small molecule organic semiconductor is elucidated, which has previously been unknown. The 3D meniscus modeling is particularly important for this analysis, as dendrite formation is strongly dependent on the meniscus geometry near the contact line and mass transport variation perpendicular to the coating direction. This technique enables the study of complex relationship between experimental parameters and solidification process, which is widely applicable to various materials and coating systems; whereby, better understanding of thin-film growth and device performance optimization is possible.

Herein, meniscus-guided crystallization is introduced as a means to grow high quality metal organic framework (MOF) thin films. A meniscus was formed between a target substrate and a coating blade,...

In this Letter, Thulium (Tm) interlayer was applied at the junction of Ni-InGaAs/n- In0.53Ga0.47As and specific contact resistivity (ρc) was derived at the junction using circular transmission line model (CTLM) procedure. The contact resistance values obtained using the CTLM were 1.65 × 10−8 and 2.11 × 10−6 Ω cm2 for a 5 nm thick Tm interlayer sample and the reference sample (without the Tm interlayer), respectively. The finding shows a drastic decrease in contact resistance and Tm interlayer reduce the contact resistance by more than two orders of magnitude compared to the reference sample. The surface and structural properties of Ni-InGaAs with Tm interlayer were characterized using XRD, FE-SEM and TEM and the elemental depth profile using SIMS analysis.

Three-dimensional (3D), highly porous, and low-density fibrous scaffolds have attracted significant interest in recent years for applications in tissue engineering. However, the fabrication of 3D fluffy fibrous piezoelectric scaffolds remains a challenge. In this study, we report the dramatic effect that relative humidity (RH) has on the deposition of 3D cotton-like constructs composed of polyvinylidene fluoride (PVDF) piezoelectric nanofibers mixed with Barium Titanate (BT) and multiwalled-carbon nanotubes (MWCNTs). The 30 mm diameter deposits were fabricated under variable humidity conditions while all other parameters were kept constant. Two types of fibrous architecture, 3D fluffy and two-dimensional (2D) membrane types, are recognized, as the RH during electrospinning varies. A fiber morphology transition takes place at certain RH, and the 3D cotton-like nanofibrous structure has been optimized above 90% RH. The fabrication of the 3D cotton-like fibrous piezoelectric scaffold may provide new insights for various applications in tissue engineering.

Since the discovery that applying electrical stimulation can promote cell growth, proliferation, and tissue regeneration, research on bio-piezoelectric materials is being actively conducted. In this study, a composite material was prepared by mixing polyvinylidene fluoride (PVDF), a conventional piezoelectric polymer, and silk fibroin (SF), a natural piezoelectric material that recently attracting attention. These two polymers were fabricated into a composite fiber mat using electrospinning technology. To find optimal conditions, SF was added in various ratios to prepare electrospun PVDF/SF mats. The characteristics of these PVDF/SF composite mats were then analyzed through various evaluations and in vitro studies. It was confirmed that PVDF and SF were successfully mixed through scanning electron microscope images and structural analysis such as x-ray diffractometer and Fourier transform infrared. The results revealed that adding an appropriate amount of SF could improve the tensile strength, enhance cell proliferation rate, and generate a voltage similar to that of a conventional PVDF-only electrospinning mat. Such fabricated electrospun PVDF/SF composite mats are expected to be useful in the bio-piezoelectric field because they can maintain piezoelectricity while compensating for the shortcomings, such as low physical properties, of a PVDF electrospun mat.

Introduction The liquid biopsy approach, a less-invasive diagnostic tool, enables the detection of disease-specific genetic and epigenetic aberrations. Approximately 66–69% of the human genome may be composed of transposable repetitive elements, including Alu and LINE-1. This study aimed to investigate whether Alu-derived cell-free DNA (cfDNA) concentrations, Alu index, and LINE-1 methylation could be used to distinguish patients with cancers from healthy individuals. Methods Two sets of primers, shorter and longer Alu fragments, were used to amplify Alu elements, followed by the quantitation of Alu DNA concentration and its integrity index. LINE-1 methylation status was then analyzed with quantitative PCR using methylation- and unmethylation-specific TaqMan probes. Results Both Alu index and LINE-1 methylation level were significantly different in comparison between patients with lung or breast cancer and the healthy controls. The area under the ROC curve of the Alu index and LINE-1 hypomethylation was 0.742 and 0.848 for lung cancer, respectively, and 0.724 and 0.890 for breast cancer, respectively. However, Alu longer fragment DNA concentration was significantly correlated with Alu index in comparison to LINE-1 hypomethylation. Regression analysis suggested that the LINE-1 methylation level, rather than the Alu index, was a good discriminator for lung and breast cancers. Conclusions This study investigated the genome-wide Alu index and LINE-1 methylation status; their associations with cancers suggested that these combinatory panels could be implemented as a triage test to discriminate cancer patients from healthy individuals.

Currently, due to the lack of precise control of flow behavior and the understanding of how it influences thin-film crystallization, strict tuning of thin-film properties during solution-based coating is difficult. In this work, a continuous-flow microfluidic-channel-based meniscus-guided coating (CoMiC) is introduced, which is a system that enables manipulation of flow patterns and analysis connecting flow pattern, crystallization, and thin-film properties. Continuous supply of a solution of an organic semiconductor with various flow patterns is generated using microfluidic channels. 3D numerical simulations and in situ microscopy allow the tracking of the flow pattern along its entire path (from within the microfluidic channel to near the liquid-solid boundary), and enable direct observation of thin-film crystallization process. In particular, the generation of chaotic flow results in unprecedented device-to-device uniformity, with coefficient of variation (CV) of 7.3% and average mobility of 2.04 cm2 V-1 s-1 in doped TIPS-pentacene. Furthermore, CV and average mobility of 9.6% and 11.4 cm2 V-1 s-1 are achieved, respectively, in a small molecule:polymer blend system. CoMiC can serve as a guideline for elucidating the relation between flow behavior, liquid-to-solid phase transition, and device performance, which has thus far been unknown.

Cellulose and its derivatives are widely used as nanofibrous biomaterials, but obtaining 3D cellulose nanofibers is difficult and relevant research is scarce. In the present study, we propose a simple method for converting electrospun 3D cellulose acetate/lactic acid nanofibers via calcium hydroxide treatment into a 3D cellulose/calcium lactate nanocomposite matrix. The conversion resulted in producing a stronger nanofibrous matrix (1.382 MPa vs. 0.112 MPa) that is more hydrophilic and cell-friendly compared to the untreated cellulose acetate/lactic acid group. The successful conversion was verified via FTIR, XPS, TGA, DTG, and XRD. The ability of the scaffolds to provide a suitable environment for cell growth and infiltration was verified by CCK assay and confocal microscopy. The porous nature, mechanical strength, and presence of calcium make the 3D cellulose/calcium lactate matrix a promising material for bone tissue engineering.

N-diethylnitrosamine (DEN), a well-known carcinogen, not only induces excessive reactive oxygen species but also suppresses DNA methylation. This study investigated the effect of fermented rice bran (FRB) treatment on DEN-induced oxidative stress through DNA methylation and telomere length analysis. To evaluate the potential protective role of FRB in oxidative stress, two different doses of FRB, DEN, and their combination were administered to mice that were preadapted or not to FRB. Glutathione-S-transferase P1 (GSTP1) methylation levels significantly decreased at 2 and 24 hr after FRB and DEN co-administration in mice with and without pre-adaptation. Moreover, GSTP1 mRNA was upregulated under DEN-induced oxidative stress. Furthermore, changes in long interspersed nuclear element-1 methylation were observed from the viewpoint of genomic instability. In addition, FRB preadapted mice displayed a lower telomere length ratio than the non-adapted mice, suggesting that FRB adaptation offers advantages over the non-adapted conditions in terms of inflammation suppression. PRACTICAL APPLICATIONS: DEN induces excessive ROS, which is associated with oxidative stress on DNA and other cellular components, resulting in inflammation. This study shows that FRB may alleviate DEN-triggered oxidative stress, based on changes in GSTP1, LINE-1 methylation, and telomere length ratios, thereby, revealing the potential of dietary intervention during inflammation. Furthermore, this study furthers the current understanding of DNA methylation mechanisms underlying the antioxidant and anti-inflammatory effects of functional food components. These results indicate that dietary inclusion of FRB may help decrease oxidative DNA damage and its associated inflammation at early stages of a disease.

Ultra-low contact resistance at the interface between NiGe and p-Ge, i.e., NiGe/p-Ge was achieved by introducing terbium (Tb) as an interlayer in forming NiGe using Tb/Ni/TiN structure. The contact resistance value obtained using the circular transmission line model for an 8-nm thick Tb interlayer sample was 7.21 × 10−8 Ω·cm2, which is two orders of magnitude less than that of reference sample (without the Tb interlayer) of 7.36 × 10−6 Ω·cm2. The current–voltage characteristics were studied at a temperature range of −110 ~ 25 °C to determine the effective Schottky barrier height (eSBH). An eSBH of 0.016 eV was obtained for the 8-nm thick Tb interlayer. Various Tb interlayer thicknesses were selected to study their effect on the contact resistance. The Tb interlayer surface and structural properties were characterized using FESEM, XRD, XPS, TEM, and SIMS analyses.

Epigenetic dysregulation has been known to be involved in neurodegenerative diseases, including amnestic mild cognitive impairment (MCI). The aim of this study was to investigate the genome-wide DNA methylation analysis, in order to identify epigenetic dysregulation in blood from patients with MCI. Here, we investigated whether epigenetic dysregulation in MCI and whether such an aberration could be detected in blood circulation. Genome-wide bisulfite sequencing targeted 84 million bases covering 3.7 million CpG sites was comparatively analyzed in MCI and control groups. And correlation between DNA methylation and transcriptomic changes was sought. Significant differentially methylated regions (DMRs) distinguishing the MCI and control groups were identified and functionally annotated. Most DMRs specific to MCI were enriched between - 2 kb and + 2 kb of the CpG island start sites located within or near gene promoters. Representative hypo- and hypermethylated DMRs in MCI were confirmed to be correlated to mRNA expression changes with the comparative delta Ct method. DNA methylation aberrations involving metal ion homeostasis, axon growth, inflammasome, and others in this study may be less-invasive, easily measurable blood biomarker candidates for MCI.

Solution-based thin-film processing is a widely utilized technique for the fabrication of various devices. In particular, the tunability of the ink composition and coating condition allows precise control of thin-film properties and device performance. Despite the advantage of having such tunability, the sheer number of possible combinations of experimental parameters render it infeasible to efficiently optimize device performance and analyze the correlation between experimental parameters and device performance. In this work, a microfluidic screening-embedded thin-film processing technique is developed, through which thin-films of varying ratios of small molecule semiconductor:polymer blend are simultaneously generated and screened in a time- and resource-efficient manner. Moreover, utilizing the thin-films of varying combinations of experimental parameters, machine learning models are trained to predict the transistor performance. Gaussian Process Regression (GPR) algorithms tuned by Bayesian optimization shows the best predictive accuracy amongst the trained models, which enables narrowing down of the combinations of experimental parameters and investigation of the degree of vertical phase separation under the predicted parameter space. The technique can serve as a guideline for elucidating the underlying complex parameter-property-performance correlations in solution-based thin-film processing, thereby accelerating the optimization of various thin-film devices in the future.

Aim There is growing evidence that cold-inducible RNA-binding protein (CIRP) promotes inflammatory responses. This study investigated the relationship between CIRP and rheumatoid arthritis (RA). Methods Peripheral blood and synovial fluid were collected from 15 patients with RA and from 16 patients with osteoarthritis (OA). The concentration of CIRP was measured with the sandwich enzyme-linked immunosorbent assay (ELISA). Results The concentration of serum CIRP was significantly elevated in the RA patient group (RA patients = 26.39 ± 10.48 pg/mL, OA patients = 17.14 ± 7.24 pg/mL, P = 0.009). Furthermore, the RA patient group had a significantly higher CIRP concentration than that of the OA patient group in synovial fluid (153.56 ± 108.93 pg/mL vs. 23.63 ± 16.18 pg/mL, P < 0.001). The mean synovial fluid concentration of CIRP was significantly higher than that of the serum concentration in the RA patient group (serum concentration = 26.39 ± 10.48 pg/mL, synovial fluid = 153.56 ± 108.93 pg/mL, P < 0.001). Disease Activity Score of 28 joints (DAS28)-ESR (erythrocyte sedimentation rate) and DAS28-CRP (C-reactive protein) were positively correlated with the synovial fluid concentration of CIRP (DAS28-ESR: r = 0.582, P = 0.023; DAS28-CRP: r = 0.541, P = 0.037). Conclusion The serum and synovial concentrations of CIRP in the RA patients were increased compared to the OA patients. Additionally, the synovial concentration of CIRP in RA patients correlated well with disease activity, that is, the DAS28-ESR/CRP. Based on these results, CIRP mediates inflammation and is a potential marker for synovial inflammation.

We report a new class of metal-organic framework (MOF) inks with a water-repellent, photocurable fluoropolymer (PFPE) having up to 90 wt % MOF loading. These MOF inks are enabled to process various MOFs through spray coating, pen writing, stencil printing, and molding at room temperature. Upon UV curing, the hydrophobic PFPE matrix efficiently blocks water permeation but allows accessibility of chemicals into the MOF pores, thereby freeing the MOF to perform its unique function. Moreover, by introducing functional MOFs we successfully demonstrated a water-tolerant chemosensor for a class of aromatic pollutants in water and a chemical-resistant thermosensor for visualizing temperature image. This approach would open up innumerable opportunities for those MOFs that are otherwise dormant.

746 Copyright c 2015 The Korean Association of Internal Medicine This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Received: 2015. 7. 13 Revised: 2015. 7. 20 Accepted: 2015. 8. 17

It is demonstrated that the crystal size of small-molecule organic semiconductors can be controlled during solution shearing by tuning the shape and dimensions of the micropillars on the blade. Increasing the size and spacing of the rectangular pillars increases the crystal size, resulting in higher thin-film mobility. This phenomenon is attributed as the microstructure changing the degree and density of the meniscus line curvature, thereby controlling the nucleation process. The use of allylhybridpolycarbosilane (AHPCS), an inorganic polymer, is also demonstrated as the microstructured blade for solution shearing, which has high resistance to organic solvents, can easily be microstructured via molding, and is flexible and durable. Finally, it is shown that solution shearing can be performed on a curved surface using a curved blade. These demonstrations bring solution shearing closer to industrial applications and expand its applicability to various printed flexible electronics.

Chemical reduction of micro-assembled CNT@TiO2@SiO2 leads to the formation of titanium silicide-containing Si nanotubular structures. The Si-based nanotube anodes exhibit a high capacity (>1850 mA h g-1) and an excellent cycling performance (capacity retention of >99% after 80 cycles). © 2013 The Royal Society of Chemistry.

Under certain situations, the eye pupils or heart of any human being represent the body’s states. The measurement of pupil size is one of the most immediate, accurate, and direct methods of autonomic-activity monitoring. For example, the autonomic activity of a subject in a spontaneous state or under any stimulus can be estimated through the size of the subject’s pupil, particularly through the pupil-light reflex (PLR) or pupil-size variability (PSV). Thus, the proper equipment (pupil-monitoring system) and experimental setting (dark room and pupil-image acquisition system) designed to not affect the subjects physically and emotionally have been developed.