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This study investigated the determination of detailed microstructure modeling of the trochlea of the superior oblique muscle (SOM) using micro-computed tomography (micro-CT) and modeling of a potential prototype for a trochlea implant using three-dimensional (3D) printing. We dissected 15 intact orbits of 15 embalmed cadavers. The trochleae of the SOM were detached from the periosteum. The specimens were stained by immersion in a 15% Lugol's solution. Images were reconstructed using conventional scanner software. Measurement points were determined for the middle cross section. Points P1 and P2 were selected where the SOM adjoined the curvature of the inner trochlea. They defined the inner contact points of the SOM in the inner part of the trochlea curvature. On the back of the trochlea, points P3 and P4 were selected at the uppermost and lowest points in the inner parts of the straight trochlea, respectively. Origin O was defined on the arcuate line of P 1 P 2 ^ to generate the smallest-diameter circle consisting of P1, O, and P2. We then measured the angle from O P 1 ¯ t o O P 2 ¯ , and from O P 3 ¯ t o O P 4 ¯. We also measured the distances O P 1 ¯ , O P 2 ¯ , O P 3 ¯ , a n d O P 4 ¯ for the design of a potential trochlea implant prototype using 3D-printing and micro-CT-based modeling. The distances O P 1 ¯ , O P 2 ¯ , O P 3 ¯ , a n d O P 4 ¯ were 2.2 ± 0.7, 1.4 ± 0.5, 2.7 ± 0.9, and 2.5 ± 0.4 mm (mean ± SD), respectively. The angles from O P 1 ¯ t o O P 2 ¯ , from O P 2 ¯ t o O P 4 , - and from O P 3 ¯ t o O P 4 ¯ were 100.7 ± 14.4, 66.3 ± 18.0, and 98.9 ± 24.9 degrees, respectively. The present investigation demonstrates that the high-resolution CT is a powerful imaging technique for defining the true 3D geometry of a specimen and can potentially be used to create a 3D-printed trochlea implant. [ABSTRACT FROM AUTHOR]

Inertial focusing offers passive manipulation techniques of cells or microparticles with extremely high throughput. We devised a 3D-curved triangular channel using a flexible, thin PDMS microfluidic device to control inertial focusing positions. The flexible PDMS channel is coiled to form 3D spiral channels, which can provide a convenient route to control the structural parameters including 3D curvature and curving direction. We investigated the changes in focusing positions of the 3D spiral channels depending on Re, De, particle size, and the curving direction. The Dean flows induced by 3D curvature alter the focusing positions of the straight triangular channel, which is solely determined by inertial lift forces. We found the Dean drag force not only resulted in shifting of the focusing positions but also unstabilized some of the focusing positions and changed the number of focusing positions at specific configurations. These changes in the inertial focusing positions can lead to applications, such as single-cell analysis and rare cell separation. We demonstrated that the inertial focusing position in the 3D curved triangular channel could be easily tuned to achieve single-stream focusing and size-based separations of micro particles and cells. [ABSTRACT FROM AUTHOR]

Parylene microfluidic systems have been utilized for applications requiring properties such as high chemical resistance, high internal pressure, high mechanical strength, and small heat loss. However, they have not been widely used compared to PDMS microfluidics because the device fabrication is relatively complex and surface functionalization is difficult. In this work, we introduce a simple and economic fabrication method for parylene microfluidic devices by molding and bonding using thin-film parylene A as an adhesive layer. The amine functional group from parylene A leverages as a covalent bonding source in between two parylene layers while providing the capability of functionalization of the internal surface of parylene microfluidic channel that is highly resistant to harsh chemicals at the same time. This new approach demonstrates the ability of high bonding strength (~ 4 Mpa) and eliminates the use of an additional adhesive polymer layer, which often fails to provide sufficient chemical resistance. [ABSTRACT FROM AUTHOR]

The single process CO2 capture-mineralization approach integrates methods of CO2 absorption using aqueous solvents and mineral carbonation technology to not only remove carbon dioxide quickly, but also to simultaneously produce precipitated calcium carbonate (PCC). To develop a more sustainable process, it is important to extract calcium from inexpensive raw materials such as industrial by-products. The extractant has a significant effect on the quality of the calcium carbonate produced because it determines the anion paired with the calcium cation. In this work, several calcium sources with different anions (Propionate, Acetate, Nitrate and Chloride) were applied in the single process CO2 capture-mineralization method, and their influence on the polymorph of the obtained CaCO3 was investigated. The CaCO3 produced with inorganic calcium sources predominantly exhibited a calcite structure, while the CaCO3 produced with organic calcium sources had a structure in which vaterite and calcite coexist. This result was in good agreement with our DFT calculations, which indicated the adsorption energy of the organic anions (Propionate and Acetate) were lower than the inorganic anions on the surface of vaterite. Except for chloride with its non-polar nature, in most cases, there was a strong correlation between the polymorph and the adsorption energy calculated for each surface. A mechanism for the polymorph CaCO3 formation in our single process CO2 capture-mineralization method was proposed after observing crystal formation at low concentration. [ABSTRACT FROM AUTHOR]

N/S dual-doped carbon materials were synthesized from coffee waste and cysteine for use as porous carbon electrode materials for electric double layer capacitors. The capacitance of the carbon materials was calculated from the experimental results of cyclic voltammetry and galvanostatic charge-discharge tests. The N/S-doped carbon materials obtained from heat-treatment with cysteine exhibited a higher discharge capacitance, 71.3 F/g, than that of the carbon without the cysteine treatment, 43.8 F/g, at 1 A/g. This is because the N/S dual-doped carbons possess a higher wettability than that of the other carbon material, even though the N/S doping with cysteine destroys the porous carbon structure, which reduces the BET surface area of the carbon samples. Elemental analysis was performed to determine the portions of nitrogen and sulfur elements doped into the carbon. From the XPS results, various states of nitrogen and sulfur elements were identified, and SEM/TEM images were obtained to observe their morphologies and porous structures. [ABSTRACT FROM AUTHOR]

Increased grain yield will be critical to meet the growing demand for food, and could be achieved by delaying crop senescence. Here, via quantitative trait locus (QTL) mapping, we uncover the genetic basis underlying distinct life cycles and senescence patterns of two rice subspecies, indica and japonica. Promoter variations in the Stay-Green (OsSGR) gene encoding the chlorophyll-degrading Mg++-dechelatase were found to trigger higher and earlier induction of OsSGR in indica, which accelerated senescence of indica rice cultivars. The indica-type promoter is present in a progenitor subspecies O. nivara and thus was acquired early during the evolution of rapid cycling trait in rice subspecies. Japonica OsSGR alleles introgressed into indica-type cultivars in Korean rice fields lead to delayed senescence, with increased grain yield and enhanced photosynthetic competence. Taken together, these data establish that naturally occurring OsSGR promoter and related lifespan variations can be exploited in breeding programs to augment rice yield. Breeding crops with delayed senescence could plausibly increase grain yield. Here the authors show that variation at the rice SGR locus contributes to differences in senescence between indica and japonica subspecies and show that introgression can increase yield in an elite indica rice variety. [ABSTRACT FROM AUTHOR]

Flow lithography in a conventional rectangular microchannel is limited to fabrication of particles for which only the shapes of top perimeters are controlled. We present a flow lithography technique for fabrication of microparticles of diverse 3D shapes and multiple layers using non-rectangular microchannels with designed cross sections that allow the creation of complex shapes and diverse cross-sectional shapes. Variations in cross-sectional shape allow high-throughput, on-demand production of microparticles in unconventional shapes such as tetrahedrons and pyramids. Multilayered 3D particles were generated in an enlarging triangular channel combined with on-chip PDMS valves, which allow particle alignment and fluid exchange. These 3D microparticles are expected to further expand the wide variety of applications of microparticles, especially in drug delivery and tissue engineering fields. [ABSTRACT FROM AUTHOR]

Purpose: Two-dimensional neuronal cell culture technique has helped study behaviors of neurons and neuronal networks. However, neurons in a living organism are arranged in threedimensional space, rather than tightly attached to a planar culture plate or an electrode. Besides, neurons co-exist with a large number of glial cells. For these reasons, we developed a method of making culture constructs in which neurons and glial cells were three-dimensionally co-cultured and investigated the morphological features of neural cells cultured in three-dimensional space. Additionally, we formed neural interfaces between the three-dimensionally cultured neurons and metal electrodes. Neural recording was attempted to examine possibilities and problems associated with such interfaces. Methods: Primary hippocampal neurons and astrocytes were cultured in a thermos-gelating protein-based hydrogel for more than two weeks. The functionality and the morphology of the neural cells were verified by means of FM1-43 staining and confocal microscopy, respectively. Finally, neural signal recording from neurons cultured by the proposed method was carried out with both a planar multi-electrode array and a probe-type electrode. Results: The presence of functional synapses was confirmed by the uptake and discharge of the dye, FM1-43, during high potassium stimulation. As a result of three-dimensional restoring of the confocal microscopy images, neurons were observed to extend their processes in a straighter line in three-dimensional culture constructs than in planar cultures, and astrocytes were more stellate than polygonal in terms of their shape when cultured in three-dimensional constructs. The signal strength was low or unmeasurable owing to the coarse distribution of the signal sources and the long distance from them. Conclusions: A three-dimensional co-culturing method for neural cells is developed, in which neurons and glial cells are morphologically similar to in vivo cells and functionally active. From the neural signal recording results, a more realistic density of neural cells in culturing construct need to be achieved in order to better simulate a neural interface between three-dimensionally cultured neurons and metal electrodes. [ABSTRACT FROM AUTHOR]

Acid clathrate hydrates which do not contain hydrogen fluoride impurities are believed to include several vacancy sites in the host lattice for protonation of the framework. In this work, the crystal structures of a DClO· 5.5DO solid at various temperatures were identified by the direct space method and Rietveld refinement of the neutron powder diffraction patterns. A position change of vacancy sites accompanying the shift of ClO guest ions in the 56 cavity toward the center of the cavity from the edge of the hexagonal face was observed at about 180 K, and this phenomenon is expected to result in weakened host proton-guest anion interactions and to induce a phase transition related to the proton conduction behavior of the DClO clathrate. The present findings explain the proton dynamics of the hydrogen fluoride-free acid clathrate hydrates and provide a better understanding of the nature of guest-host interactions occurring on ion-doped hydrate materials. [ABSTRACT FROM AUTHOR]

In this study, we focused on the performance of phosphate recovery in the case of magnetic iron oxide (MIO) particles and iron oxide nanotubes (INTs) with synthetic wastewater. MIO particles were prepared by a co-precipitation method, and INTs were prepared with a potentiostatic anodization method of zerovalent iron foil in electrolyte-containing sulfate and fluoride. Although MIO had the fast adsorption rate, INT had a higher adsorption capacity per surface area rather than MIO. The adsorption isotherm of MIO and INT was approximated by a Freundlich type. Phosphate adsorbed on MIO and INT was effectively desorbed with alkaline solutions. For phosphate recovery, MIO needs a magnetic recovery device, whereas, when INT was used for phosphate recovery, another recovery step is not necessary. Both methods showed effective adsorption performance for phosphate recovery in wastewater. [ABSTRACT FROM AUTHOR]

Microfluidic biopanning can reduce a sample size and improve the reproducibility of biopanning. However, there is no practical guideline for optimal experimental conditions to identify high affinity peptides, including incubation and washing times and washing and elution flow rates. Here we investigated the elution dynamics of M13 phage displaying a well-known streptavidin-binding peptide motif, histidine-proline-glutamine (HPQ), to streptavidin immobilized in a polydimethylsiloxane microfluidic channel via a biotin-polyethylene glycol linker. The phages bound to streptavidin were eluted using an acidic buffer, which weakens the molecular interactions of HPQ and streptavidin. Various washing flow rates were examined to determine the effects of drag forces on the elution of phages, and the total force per phage combined with the drag force was calculated. The critical washing drag force and washing time were 5.9×10 dyne and 1.1 min, respectively, as obtained by fitting the data using a sigmoidal function. The dissociation rate constant of HPQ-displaying phage (2.0×10 min) was also obtained from the double exponential decay fitting. Our work provides a practically useful approach to the optimization of experimental parameters for the design of a microfluidic biopanning platform. [ABSTRACT FROM AUTHOR]

Purpose: We determined the relationship between apnea severity and depressive symptoms in a large sample of the newly diagnosed male patients with severe obstructive sleep apnea (OSA). Methods: Data were collected from patients who received polysomnography due to suspected OSA. The questionnaires included the Beck Depression Inventory (BDI), Epworth Sleepiness Scale (ESS), and Medical Outcomes Study (MOS)-Sleep Scale, for which Sleep Problems Index-1 (SPI-1) was calculated. The apnea-hypopnea index (AHI) and respiratory distress index (RDI) were used to measure apnea severity. The mediational model, which states that OSA severity affects depression through a mediator, was tested here. Results: In total, 302 male patients with severe OSA participated. The mean patient age was 48.4 years (SD = 11.3 years). The BDI was ≥10 in 118 patients (39 %) and was significantly associated with body mass index ( r = 0.114; p = 0.048), ESS ( r = 0.164; p = 0.004), SPI-1 ( r = 0.453; p < 0.001), and RDI ( r = 0.126; p = 0.029). According to the linear regression analyses, the RDI is not independently associated with the BDI. The strongest predictor of BDI was sleep quality (SPI-1; β = 0.425; p < 0.001). The bootstrap method confirmed that the depressive effects of RDI are significantly mediated by poor sleep quality (bootstrapped 95 % CI 0.0113-0.0632). Conclusions: There is evidence of a mediational role of subjective sleep quality on the relationship between apnea severity and depressive symptoms in male patients with severe OSA. [ABSTRACT FROM AUTHOR]

The purpose of this study is to examine the interrelationships between manufacturing strategy process (manufacturing strategy formulation and manufacturing strategy implementation), manufacturing-marketing integration and plant performance. For this study, a survey was conducted on 221 manufacturers from the machinery, automotive and electronics in South Korea. Subsequently, the related hypotheses were tested using structural equation modeling. According to the results, positive relationships were observed between the manufacturing strategy process, manufacturing-marketing integration and plant performance. Specifically, manufacturing strategy formulation positively influenced both manufacturing strategy implementation and manufacturing-marketing integration. Further, not only manufacturing strategy implementation, but manufacturing-marketing integration also has a direct positive influence on plant performance. Although manufacturing strategy formulation does not directly affect plant performance, its influence on plant performance is transmitted through two paths intermediated by both manufacturing strategy implementation and manufacturing-marketing integration, respectively. In contrast to quite a number of studies focused on the manufacturing strategy content, there only exists a relatively small number of studies related to the manufacturing strategy process. Therefore, this study is one of the few broad empirical studies that investigated the interrelationships between manufacturing strategy formulation, manufacturing strategy implementation, manufacturing-marketing cooperation and plant performance using structural equation modeling. Furthermore, it also verified that the manufacturing strategy process can be a source of plant performance improvement. [ABSTRACT FROM AUTHOR]

In Korea, disinfection of effluent from a wastewater treatment plant is now essential, and ultraviolet (UV) disinfection is known as one of the useful disinfection alternatives. The non-contact type UV disinfection method, which is distinguished by a fouling-free process, was developed, and a mathematical model for the photoreactor was developed. For the purpose of the model calibration, the study had manufactured a non-contact type UV photoreactor and measured UV intensities within the photoreactor. The two major parameters of the model were evaluated by comparing the UV intensity of the photoreactor and the model's simulation results. As the result of this study, the developed model for a non-contact type UV photoreactor could predict UV intensity within the photoreactor well. Optima parameter values came out as measuring 576 points for the calibration test and 504 points for the verification test. The coincidence index proved useful in calibrating the parameters, with the index values over 0.9 at the optimum values. This study produced optimum values for the two parameters. The UV conversion efficiency and the transmittance of UV in pure water came out to be 0.56 and 100%, respectively. [ABSTRACT FROM AUTHOR]

Cell separation and sorting are essential steps in cell biology research and in many diagnostic and therapeutic methods. Recently, there has been interest in methods which avoid the use of biochemical labels; numerous intrinsic biomarkers have been explored to identify cells including size, electrical polarizability, and hydrodynamic properties. This review highlights microfluidic techniques used for label-free discrimination and fractionation of cell populations. Microfluidic systems have been adopted to precisely handle single cells and interface with other tools for biochemical analysis. We analyzed many of these techniques, detailing their mode of separation, while concentrating on recent developments and evaluating their prospects for application. Furthermore, this was done from a perspective where inertial effects are considered important and general performance metrics were proposed which would ease comparison of reported technologies. Lastly, we assess the current state of these technologies and suggest directions which may make them more accessible. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Novel ultrafine eutectic composites containing structural and spatial heterogeneities have been systematically developed in an Mg–Cu–Zn ternary system. Microstructural investigations of the ultrafine eutectic composites revealed that the bimodal eutectic structure consists of a mixture of cellular-type fine (α-Mg + MgZn2) and anomalous-type coarse (α-Mg + MgZn2 + MgCuZn) eutectic structures. An Mg72Cu5Zn23 alloy composed of the bimodal eutectic structure without micron-scale α-Mg dendrites presents a strong improvement of yield strength up to 455 MPa with a decent plastic strain of 5%. The rotation of the bimodal eutectic colony along the interfaces is considered to be an effective way to dissipate the stress localization thus enhancing the macroscopic plasticity. [ABSTRACT FROM AUTHOR]

Thin TiO2 layers grown at 130°C on SiO2-coated Si substrates by atomic layer deposition (ALD) using TTIP and H2O as precursors were annealed, and the effects of the annealing temperature on the resulting electrical properties of TiO2 and the interface properties between a Pt electrode and TiO2 were examined using transmission line model (TLM) structures. The as-deposited TiO2 thin film had an amorphous structure with OH groups and a high resistivity of 6×103Ω-cm. Vacuum annealing at 700 °C transformed the amorphous film into an anatase structure and reduced its resistivity to 0.04Ω-cm. In addition, the vacuum-annealing of the TiO2/SiO2 structure at 700°C produced free silicon at the TiO2-SiO2 interface as a result of the reaction between the Ti interstitials and SiO2. The SiO2 formed on the TiO2 surface caused a Schottky contact, which was characterized by the TLM method. The use of the TLM method enabled the accurate measurement of the resistivity of the vacuum-annealed TiO2 films and the characterization of the Schottky contacts of the metal electrode to the TiO2. [ABSTRACT FROM AUTHOR]