77 research outputs found
Flexible Organic Crystals for Light Delivery in Biological Tissues
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Optically transmissive materials are indispensable for the transmission of light or light-encoded signals in telecommunications and optobiomedical techniques. Here, we propose that slender crystals of small organic molecules can be used as optically transparent, flexible, lightweight, and emissive media to deliver photons into or through biological tissues as an alternative to silica- or polymer-based light waveguides. We demonstrate that organic crystals remain transmissive in various porcine tissues, and their efficiency in light transduction depends on the intrinsic optical properties of the crystal, optical path, geometry of excitation, and the type of tissue. Moreover, elastically or plastically deformable organic crystals remain mechanically compliant and can be bent after they have been embedded in the tissue, opening prospects for designing a new class of biocompatible light waveguiding elements based on crystalline organic materials. In vivo implantation and toxicity assays capitalize on mechanical flexibility and biocompatibility in animal models. Within a broader context, the high transparency, anisotropy, and biocompatibility of some organic crystals turn this emerging class of materials into a prospective platform for delivering photons for specific interaction with target cells in tissues for applications such as photodynamic therapy and optogenetics
Central Aortic Systolic Blood Pressure Exhibits Advantages Over Brachial Blood Pressure Measurements in Chronic Kidney Disease Risk Prediction in Women
Background/Aims: To investigate whether the invasively obtained central aortic systolic blood pressure (CSBP) predicts chronic kidney disease (CKD) better than brachial systolic blood pressure (SBP), brachial diastolic blood pressure (DBP) and brachial pulse pressure (PP) in the middle-aged Chinese population. Methods: A cross-sectional study was carried out across China in 2009-2010 among the subjects aged 35-64 years. CSBP was measured non-invasively by radial artery applanation tonometry B-pro (A-PULSE CASP and corresponding software). CSBP, SBP, DBP and PP were standardized with Z-score and the odds ratios were calculated with multivariable logistic regression model. Results: Data of 10197 participants were analyzed. The multivariable logistic regression after adjusting for possible confounders showed that a 1-standard deviation increment in each blood pressure measurement was associated with greater risk of CKD in both men and women (P < 0.05). The association of CSBP with CKD was stronger than SBP, DBP and PP in women, while in men the association of CSBP with CKD was stronger only than PP. With CSBP and SBP entering into the multivariable logistic regression models jointly, the odds ratio (95% confidence interval) for CSBP and SBP was 1.57 (1.39-1.79) and 1.22 (1.07-1.38) in women and 1.20 (1.03-1.39) and 1.48 (1.28-1.72) in men, respectively. With CSBP and DBP entering into the multivariable logistic regression models jointly, the odds ratio (95% confidence interval) for CSBP and DBP was 1.68 (1.52-1.84) and 1.15 (1.04-1.27) in women and 1.30 (1.15-1.46) and 1.45 (1.29-1.63) in men, respectively. With CSBP and PP entering into the multivariable logistic regression models jointly, the odds ratio (95% confidence interval) for CSBP and PP was 1.75 (1.58-1.94) and 1.06 (0.96-1.17) in women and 1.58 (1.41-1.77) and 1.04 (0.93-1.17) in men, respectively. Conclusion: CSBP and brachial blood pressure measurements are all predictors of CKD, however the non-invasively obtained CSBP may offer advantages over brachial blood pressure measurements in CKD risk prediction in women
Identification of key regulatory pathways and genes involved in the dynamic progression of pigmentation in Sinibrama taeniatus
IntorductionColoration is a prominent trait in fish that is closely linked to their market value. Fish exhibit a diverse range of body colors, making them an excellent model for studying molecular mechanisms underlying pigmentation. Although regulatory pathways involved in pigmentation have been extensively studied in model fish such as zebrafish and medaka, the presence of varying chromatophore types across different fish species suggests that fish pigmentation mechanisms are not fixed. Therefore, more studies should be conducted on non-model fish. Sinibrama taeniatus is an endemic fish in the upper Yangtze River that is highly valued for its ornamental and edible properties.MethodsIn this study, we identified three chromatophore types in S. taeniatus and investigated changes in body color, chromatophores, and pigments at different developmental stages. Subsequently, RNA-seq analysis revealed that retinol metabolism, thyroid hormone synthesis, purine metabolism, and pyrimidine metabolism pathway are closely associated with pigmentation.ResultsWeighted gene co-expression network analysis (WGCNA) identified several hub genes, including mitf, wnt 9a, wnt10b, wnt11, adcy5, edn1, adcy8, and rdh8, that may play an important role in pigmentation.DiscussionOverall, our findings provide valuable insights into the role of genes and pathways in fish pigmentation and offer useful information for body color-based molecular breeding programs in aquaculture
産業用ロボットマニピュレータの高性能制御に関する研究
九州工業大学博士学位論文 学位記番号:情工博甲第287号 学位授与年月日:平成26年3月25日1 Introduction||2 A new interpolation methodology for position command||3 Decoupling control by using Model Following Control||4 Identification of joint friction||5 Conclusion
Remote and precise control over morphology and motion of organic crystals by using magnetic field
Elastic organic crystals are the materials foundation of future lightweight flexible electronic, optical and sensing devices, yet precise control over their deformation has not been accomplished. Here, we report a general non-destructive approach to remote bending of organic crystals. Flexible organic crystals are coupled to magnetic nanoparticles to prepare hybrid actuating elements whose shape can be arbitrarily and precisely controlled simply by using magnetic field. The crystals are mechanically and chemically robust, and can be flexed precisely to a predetermined curvature with complete retention of their macroscopic integrity at least several thousand times in contactless mode, in air or in a liquid medium. These crystals are used as optical waveguides whose light output can be precisely and remotely controlled by using a permanent magnet. This approach expands the range of applications of flexible organic crystals beyond the known limitations with other methods for control of their shape, and opens prospects for their direct implementation in flexible devices such as sensors, emitters, and other (opto)electronics
Trifluoromethyl-Substituted Large Band-Gap Polytriphenylamines for Polymer Solar Cells with High Open-Circuit Voltages
Two large band-gap polymers (PTPACF and PTPA2CF) based on polytriphenylamine derivatives with the introduction of electron-withdrawing trifluoromethyl groups were designed and prepared by Suzuki polycondensation reaction. The chemical structures, thermal, optical and electrochemical properties were characterized in detail. From the UV-visible absorption spectra, the PTPACF and PTPA2CF showed the optical band gaps of 2.01 and 2.07 eV, respectively. The cyclic voltammetry (CV) measurement displayed the deep highest occupied molecular orbital (HOMO) energy levels of −5.33 and −5.38 eV for PTPACF and PTPA2CF, respectively. The hole mobilities, determined by field-effect transistor characterization, were 2.5 × 10−3 and 1.1 × 10−3 cm2 V−1 S−1 for PTPACF and PTPA2CF, respectively. The polymer solar cells (PSCs) were tested under the conventional device structure of ITO/PEDOT:PSS/polymer:PC71BM/PFN/Al. All of the PSCs showed the high open circuit voltages (Vocs) with the values approaching 1 V. The PTPACF and PTPA2CF based PSCs gave the power conversion efficiencies (PCEs) of 3.24% and 2.40%, respectively. Hence, it is a reliable methodology to develop high-performance large band-gap polymer donors with high Vocs through the feasible side-chain modification
Influence of Hydrogen Ions on the Performance of Thin-Film Transistors with Solution-Processed AlOx Gate Dielectrics
Over the past decade, there have been many reports on solution-processed oxide thin-film transistors (TFTs) with high mobility (even >100 cm2 V−1s−1). However, the capacitance uncertainty of the solution-processed oxide gate dielectrics leads to serious overestimation of the mobility. Here, solution-processed AlOx dielectrics are investigated systematically, and the effect of mobile ions on the frequency-dependent capacitance of the solution-processed AlOx dielectrics is also studied. It was found that the capacitance of the AlOx depends on the frequency seriously when the annealing temperature is lower than 300 °C, and the water treatment causes more seriously frequency-dependent capacitance. The strong frequency-dependent capacitance of the AlOx annealed at 250 or 300 °C is attributed to relaxation polarization of the weakly bound ions in the incompletely decomposed AlOx films. The water treatment introduces a large number of protons (H+) that would migrate to the ITO/AlOx interface under a certain electric field and form an electric double layer (EDL) that has ultrahigh capacitance at low frequency
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