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In this paper, a new hybrid manufacturing process was proposed to fabricate biomimetic intestinal villi. The hybrid process consists of two steps, i.e., a micro-drilling process to make steep holes and a laser-based machining process to smoothen their geometries. Polycarbonate (PC) was used as a candidate material for mold, and villi’s scaffold was fabricated using polydimethylsiloxane (PDMS). For the hybrid manufacturing process, conditions of the micro-drilling process were optimized first and then a series of laser-based machining experiments were performed using the pre-produced micro-drilled molds. A full factorial design of experiments was conducted to investigate the effects of laser power, air, and the objective lens, and the shape of villi was observed as an output to evaluate the process performance. Experimental results demonstrated that the proposed hybrid manufacturing process is able to fabricate villi whose geometry is consistent and suitable for cell culturing. Consequently, villi scaffold with various dimensions could be conveniently built using different parameters, and it could be applied to personalized organ-on-a-chip applications in the future.

Nanoliposomal irinotecan (nal-IRI) is a liposomal formulation of irinotecan with a longer half-life (t1/2 ), higher plasma total irinotecan (tIRI), and lower SN-38 maximum concentration (Cmax ) compared with nonliposomal irinotecan. Population pharmacokinetic (PK) analysis of nal-IRI was performed for tIRI and total SN-38 (tSN38) using patient samples from six studies. PK-safety association was evaluated for neutropenia and diarrhea in 353 patients. PK-efficacy association was evaluated from a phase III study in pancreatic cancer NAPOLI1. Efficacy was associated with longer duration of unencapsulated SN-38 (uSN38) above a threshold and higher Cavg of tIRI, tSN38, and uSN38. Neutropenia was associated with uSN38 Cmax and diarrhea with tIRI Cmax . Baseline predictive factors were race, body surface area, and bilirubin. Analysis identified PK factors associated with efficacy, safety, and predictive baseline factors. The results support the benefit of nal-IRI dose of 70 mg/m2 (free-base; equivalent to 80 mg/m2 salt base) Q2W over 100 mg/m2 Q3W.

Background and objective Retinal imaging has two major modalities, traditional fundus photography (TFP) and ultra-widefield fundus photography (UWFP). This study demonstrates the feasibility of a state-of-the-art deep learning-based domain transfer from UWFP to TFP. Methods A cycle-consistent generative adversarial network (CycleGAN) was used to automatically translate the UWFP to the TFP domain. The model was based on an unpaired dataset including anonymized 451 UWFP and 745 TFP images. To apply CycleGAN to an independent dataset, we randomly divided the data into training (90%) and test (10%) datasets. After automated image registration and masking dark frames, the generator and discriminator networks were trained. Additional twelve publicly available paired TFP and UWFP images were used to calculate the intensity histograms and structural similarity (SSIM) indices. Results We observed that all UWFP images were successfully translated into TFP-style images by CycleGAN, and the main structural information of the retina and optic nerve was retained. The model did not generate fake features in the output images. Average histograms demonstrated that the intensity distribution of the generated output images provided a good match to the ground truth images, with an average SSIM level of 0.802. Conclusions Our approach enables automated synthesis of TFP images directly from UWFP without a manual pre-conditioning process. The generated TFP images might be useful for clinicians in investigating posterior pole and for researchers in integrating TFP and UWFP databases. This is also likely to save scan time and will be more cost-effective for patients by avoiding additional examinations for an accurate diagnosis.

Germanium-based multimetallic-oxide materials have attracted significant attention as high-capacity anodes for next generation lithium-ion batteries (LIBs). However, they suffer from poor cyclic stability due to extreme volume expansion and reduced electrical conductivity after repeated cycles. To circumvent these issues, we propose that Ge-based multimetallic-oxide nanowires can be synthesized with electrically conductive carbon to significantly enhance the cyclic stability of the Ge-based anodes. We prepare conformal-carbon-coated Zn 2 GeO 4 nanowires (NWs) using a microwave-induced hydrothermal method with subsequent thermal decomposition. The obtained carbon-coated Zn 2 GeO 4 -NW anode exhibits a discharge capacity of 485 mAh/g and a Coulombic efficiency (CE) of 98.4% after 900 cycles at 0.6 C. Furthermore, these anodes exhibit outstanding rate-capability characteristics, even with an increased C-rate of 17.7 C. This excellent electrochemical performance can be ascribed to the improved electron and ion transport provided and the structurally reinforced conductive layer comprising a conformal carbon layer. Therefore, it is expected that our approach can also be applied to other multimetallic-oxide materials, resulting in large, reversible capacities; excellent cyclic stabilities; and good rate capabilities for high-performance LIBs.

The commercialization of Sn-based anodes for lithium ion batteries is still hindered due to the inherent volume change leading to a rapid capacity fading during the electrochemical cycle. Inspired by echeveria , a plant that stores sufficient water in its hierarchical leaves to survive in a drought, we report a breakthrough by designing the hierarchical and nanoporous SnO 2 electrode encapsulated with ultrathin carbon layer (∼2 nm). As evidently captured by in situ transmission electron microscopy, the conformal carbon coating on the surface of anode may provide an elastic cover that suppresses the cracks due to severe volume change, and increases both electrical and ionic conductivity, allowing the cells to exhibit excellent lithium storage performance with more than 800 cycles even with relatively high-rate of current densities.

This work describes a self-assembly method of gold nanoparticles coating on the surface of silicon thin films for the anode material of lithium secondary batteries. The preparation of the silicon thin films was carried out by electron cyclotron resonance metal organic chemical vapor deposition (ECR-MOCVD) process. The obtained films were further coated with (3-aminopropyl)-trimethoxysilane (APTMS) which has a role to bind the oxygen functional groups on Si surface and the gold nanoparticles. The dispersed gold nanoparticles on the surface of silicon thin films could be prepared due to self-assembly phenomena which interact between attraction and repulsion in gold nanoparticles colloidal solution (GNCS). The use of reducing agent of sodium citrate and tannic acid in GNCS significantly affected the size of gold nanoparticle in our experimental range. Based on our experimental results, the higher reversible capacity was exhibited for the silicon that was immersed in the GNCS consisted of only sodium citrate. The GNCS consisted of both sodium citrate and tannic acid produced severe coagulated nanoparticles when deposited on the silicon surface and thus inhibited the lithium movement from electrolyte to silicon surface. Consequently, the reversible capacity of silicon anode material with coagulated gold nanoparticles coating showed the reduced performance.

Nanostructured silicon synthesis by surface modification of commercial micro-powder silicon was investigated in order to reduce the maximum volume change over cycle. The surface of micro-powder silicon was modified using an Ag metal-assisted chemical etching technique to produce nanostructured material in the form of bundle-type silicon nanorods. The volume change of the electrode using the nanostructured silicon during cycle was investigated using an in-situ dilatometer. Our result shows that nanostructured silicon synthesized using this method showed a self-relaxant characteristic as an anode material for lithium ion battery application. Moreover, binder selection plays a role in enhancing self-relaxant properties during delithiation via strong hydrogen interaction on the surface of the silicon material. The nanostructured silicon was then coated with carbon from propylene gas and showed higher capacity retention with the use of polyacrylic acid (PAA) binder. While the nano-size of the pore diameter control may significantly affect the capacity fading of nanostructured silicon, it can be mitigated via carbon coating, probably due to the prevention of Li ion penetration into 10 nano-meter sized pores.

Practical application of silicon anodes for lithium-ion batteries has been mainly hindered because of their low electrical conductivity and large volume change (ca. 300%) occurring during the lithiation and delithiation processes. Thus, the surface engineering of active particles (material design) and the modification of electrode structure (electrode design) of silicon are necessary to alleviate these critical limiting factors. Silicon/carbon core–shell particles (Si@C, material design) are prepared by the thermal decomposition and subsequent three-dimensional (3D) electrode structures (electrode design) with a channel width of 15 μm are incorporated using the laser ablation process. The electrochemical characteristics of 3D Si@C used as the anode material for lithium-ion batteries are investigated to identify the effects of material and electrode design. By the introduction of a carbon coating and the laser structuring, an enhanced performance of Si anode materials exhibiting high specific capacity (>1200 mAh g −1 over 300 cycles), good rate capability (1170 mAh g −1 at 8 A g −1 ), and stable cycling is achieved. The morphology of the core–shell active material combined with 3D channel architecture can minimize the volume expansion by utilizing the void space during the repeated cycling.

Engineered silicon and carbon composite materials have been demonstrated to be promising anode materials for lithium-ion batteries. In this paper, we demonstrate a facile approach to fabricating silicon/carbon composite electrodes via simple mixing of silicon nanoparticles (SNPs) and carbon nanospheres (CNSs). Size-monodisperse CNSs were obtained by the direct carbon conversion of polystyrene spheres. The mixture of SNPs with size-monodisperse CNSs allowed for a uniform dispersion with minimal SNP aggregation, which was evaluated through direct comparison of the SNP mixture with micrometer-sized carbon particles. This SNP/CNS composite electrode, containing 30 wt% SNPs, exhibited a reversible specific capacity of 1023 mA h g−1 at 100 mA g−1, which was more than three times higher than that of a bare CNS electrode. The capacity retention after 50 cycles was 73%, with a high Coulombic efficiency of 99%; in addition, the capacity retention was approximately 70% when the current density was increased tenfold. Specifically, the SNP/CNS electrode exhibited substantially less capacity fade than did SNPs dispersed in micrometer-sized carbon particles. Moreover, the SNP/CNS electrode exhibited improved capacity retention under high-current-density conditions compared to that of previously developed silicon/carbon composite anodes. We attributed this improved LIB performance to the uniform dispersion of SNPs in the CNS matrix, which resulted in stable SEI formation and effective accommodation of the volume change of silicon. We believe our CNS structures can be extended to other electrode-material systems that require a large volume change and good mass transport characteristics.

The confinement and uniform dispersion of Si nanoparticles (NPs) in a carbon matrix is a promising strategy to accommodate the problematic large volume change of high-capacity Si-based anodes during charging/discharging in lithium-ion batteries. Here, we introduced an inverse opal carbon (IOC) matrix for Si NPs dispersion. A macroporous, highly interconnected porous structure of IOCs allowed uniform dispersion of Si NPs by simple mixing, and large voids that surrounded the Si NPs. The Si NPs/IOC composite anode exhibited a specific capacity up to 1233 mA g−1 with 40 wt% Si NPs content, which was 4.1 times higher than the IOC anode. The capacity retention over 50 cycles for the Si NPs/IOC anode (40 wt% Si NPs/IOC) was as high as 81%, whereas the Si NPs anode revealed only 48% retention. The specific capacity was also maintained up to 70% as the current density increased 20-fold. These enhancement of the capacity retention and the current density were attributed to the efficient accommodation of the Si volume change in the IOC structure and facile charge transport in and through the IOC matrix. We believe this simple geometry-derived approach for the dispersion of nanoparticles may be advantageous in the practical application of high-capacitive nanomaterials for next-generation lithium ion battery (LIB) development.

This study investigates bundle-type silicon nanorods (BSNR) that are aimed at improving the discharge capacity and life cycle characteristics of secondary cells, by controlling the shape and etching depth of silicon thick-films produced by electroless etching. The prepared BSNR structure is composed of a columnar bundle, having a diameter of 100 nm and lengths of 1.5 and 3.5 μm. The etching depths of the nanorods have a significant effect on the electrochemical performance characteristics, including the capacity fading and coulombic efficiency. Using a BSNR electrode therefore allows for an anode with a high capacity and efficiency in lithium ion cells, and can help overcome the issues associated with conventional silicon thick-films. Furthermore, as a result of its unique self-relaxant structure, electrode deterioration is improved through mitigation of the volume change.

We hypothesized that the ocular dominance associated with brain asymmetry would influence macular structure. We assessed the structural asymmetry of the macula by ocular dominance.A total of 144 patients with no ophthalmic abnormalities were examined. After classifying eyes as dominant or non-dominant using the hole-in-a-card test, the macular ganglion cell inner plexiform layer and the macular thickness were measured in both groups using spectral domain optical coherence tomography, and we sought associations between ocular dominance and retinal thickness.Ocular dominance was more frequently found in right eyes than in left eyes (68.75% vs 31.25%, respectively; p0.001). Using conditioned logistic regression, the right eye and the temporal-to-nasal retinal thickness ratio of the macular ganglion cell inner plexiform layer were selected as a final model for the determination of ocular dominance (p0.001, p = 0.013 respectively).Macular vertical asymmetry was associated with ocular dominance. The macular structure and ocular dominance associated with visual cortex lateralization have functional and structural relationships.

Nuclear magnetic resonance (NMR) spectroscopy has provided a unique opportunity to study the characteristic smectic-A to chiral nematic phase transition in a dimesogenic liquid crystal (“KI-5S”). The order parameters in the liquid crystalline phases were obtained from the 2 H NMR quadrupole splitting and 13 C NMR chemical shift measurements, manifesting a first-order smectic-nematic phase transition.

Carbon coated prickle-like Si particles (PS@C) are prepared by metal-assisted chemical etching and subsequent coating with an amorphous carbon film carried out by thermal chemical vapor deposition (CVD). The electrochemical characteristics of PS@C employed as anode material for lithium-ion batteries are investigated in order to find a relationship between interfacial properties and electrochemical performance. The unique morphology of prickle-like Si (PS) having empty space can accommodate volume expansion during the lithiation and delithiation. Additionally, an amorphous carbon coating layer with a thickness of 10–15 nm deposited onto the PS prepared by thermal CVD is investigated as an effective way to enhance the cycle stability and rate capability of the PS electrode due to improved interfacial characteristics. The micro and nano hybrid structure of the PS material combined with the 12 wt.% amorphous carbon layer plays an important role in enhancing the electrochemical performance.

The electrochemical and compositional changes of a solid electrolyte interphase (SEI) layer formed on the surface of silicon thin film are investigated in order to determine the effect of the content of fluoroethylene carbonate (FEC) additive in the electrolyte. Comparisons are made with FEC-free electrolyte, in which the major components are (CH 2 OCO 2 Li) 2 and Li 2 CO 3 . The (CH 2 OCO 2 Li) 2 and Li 2 CO 3 of the SEI layer in the FEC-containing electrolyte decreases, and polycarbonate and LiF increase relatively with the repression of –OCO 2 Li groups. The additive affects the composition of the SEI layer, which leads to lower resistance. The electrochemical performance regarding cycle retention, coulombic efficiency, rate capability, and discharge capacity in the FEC-containing cell are significantly enhanced compared to that of the FEC-free electrolyte. The observed optimum FEC concentration in the electrolyte is 1.5%, due to the reduced charge transfer and SEI resistance in our experimental range.

Although Si is a promising high-capacity anode material for Li-ion batteries (LIB), it suffers from capacity fading due to excessively large volumetric changes upon Li insertion. Nanocarbon materials have been used to enhance the cyclic stability of LIB anodes, but they have an inherently low specific capacity. To address these issues, we present a novel ternary nanocomposite of Si, Mn, and reduced graphene oxide (rGO) for LIB anodes, in which the Si-Mn alloy offers high capacity characteristics and embedded rGO nanosheets confer structural stability. Si-Mn/rGO ternary nanocomposites were synthesized by mechanical complexation and subsequent thermal reduction of mixtures of Si nanoparticles, MnO2 nanorods, and rGO nanosheets. Resulting ternary nanocomposite anodes displayed a specific capacity of 600 mAh/g with ∼90% capacity retention after 50 cycles at a current density of 100 mA/g. The enhanced performance is attributed to facilitated Li-ion reactions with the MnSi alloy phase and the formation of a structurally reinforced electroconductive matrix of rGO nanosheets. The ternary nanocomposite design paradigm presented in this study can be exploited for the development of high-capacity and long-life anode materials for versatile LIB applications.

Si nanostructures with high surface area are prepared by Ag-assisted chemical etching, and then employed as an anode material for lithium ion batteries. The use of the surface-modified Si, which has four times higher surface area than its pristine counterpart, leads to the enhancement of electrochemical performance characteristics such as discharge capacity and coulombic efficiency. In order to optimize the electrode constituents, two different binders, poly-vinylidine difluoride (PVdF) and polyimide (PI), are evaluated on the basis of electrochemical and physical tests. In-situ dilatometer and nano-indentation studies during repeated charging and discharging cycles for the different binders reveal more stability and recuperative capability against physical stress with the PI binder than with the PVdF. The optimized active structure combined with the film-like binder plays an important role in enhancing the electrochemical performance.

Purpose. To assess the correlations of myopicβ-zone parapapillary atrophy (β-PPA) with the optic nerve head (ONH) and retina.Methods. We selected 27 myopic patients who showed prominentβ-PPA in one eye and noβ-PPA in the other eye. We studied their macula, macular ganglion cell-inner plexiform layer (mGCIPL), peripapillary retinal nerve fiber layer (pRNFL) thickness, and ONH parameters using optical coherence tomography.Results. The average of five out of six sectors and minimum values of mGCIPL thicknesses in eyes with prominentβ-PPA discs were significantly less than those of the control eyes. The results of clock-hour sector analyses showed significant differences for pRNFL thickness in one sector. In the ONH analyses, no significant difference was observed between myopicβ-PPA and control eyes. The macular thickness of theβ-PPA eyes was thinner than control eyes in all sectors. There was a significant difference between the two groups in three sectors (the inner superior macula, inner temporal macula, and inner inferior macula) but there was no significant difference in the other sectors, including the fovea.Conclusions. The myopicβ-PPA eyes showed thinner mGCIPL, parafovea, and partial pRNFL layers compared with myopic eyes withoutβ-PPA.

This research experimentally investigates the characteristics of micro end-milling process of titanium alloy using nanofluid minimum quantity lubrication (MQL) with chilly CO2 gas. In the nanofluid MQL, hexagonal boron nitride (hBN) particles having a lamellar structure are used. They have high aspect ratio and enable sliding against other particles, which can provide better lubricity. In addition, the chilly CO2 gas enhances a cooling effect during the micro end-milling process. A series of micro end-milling experiments are conducted in the meso-scale machine tool system, and milling force, coefficient of friction, surface roughness and tool wear are observed and analyzed according to varying lubrication and cooling conditions. The results show that the nanofluid MQL with chilly gas can be effective for reducing milling forces, coefficient of friction, tool wear and improving surface quality.

Purpose To investigate the characteristics of macular ganglion cell-inner plexiform layer (GCIPL) thickness profiles associated with ocular dominance. Setting Private practice, Seoul, Republic of Korea. Design Comparative case-control study. Methods Both eyes of 199 participants with no ophthalmic abnormalities were included. Participants were imaged by spectral-domain optical coherence tomography, and underwent dominant eye testing using a hole-in-a-card test (sighting dominance) at the same visit. Macular GCIPL, as well as circumpapillary retinal nerve fiber layer (RNFL) thickness were compared for individual patients, according to ocular dominance. Results Ocular dominance occurred predominantly in the right eye (right vs. left: 72.36 vs. 27.60%; P < 0.001). In the comparison of macular GCIPL thickness, the average (81.27±5.01 μm vs. 80.66±6.31 μm in dominant vs. non-dominant eyes), inferonasal (81.39±5.47μm vs. 80.33±6.82μm, and inferior sectors (77.95±6.05μm vs. 76.97±8.15μm) were significantly different between dominant and non-dominant eyes (P = 0.040, 0.005, and 0.032, respectively). Significant predictors of average GCIPL thickness were spherical equivalent (β = 1.37, P

The thickness-dependent properties of amorphous Sn-doped In2O3 (ITO) and polycrystalline Ga-doped ZnO (GZO) films grown on polyethylene terephthalate (PET) with a polymeric hard coating were compared with those deposited on Corning glass. The film thickness varied from 20 to 1310 nm. The electrical properties of the ITO films on PET were almost similar to those of the ITO films on glass. On the other hand, GZO films showed slightly poorer electrical properties when deposited on PET, but the difference was marginal. The electrical properties of amorphous ITO films were independent of film thickness, but polycrystalline GZO films exhibited monotonicallyimproving behavior with increasing thickness, mainly due to enhanced crystallinity and increased grain size with increasing film thickness. Although the air-referenced transmittance spectra of films on PET were about 2–3% lower than those on glass due to the lower transmittance of PET, the substrate-referenced optical transmittances of films on PET were higher than those on glass, reflecting the somewhat coarse structure of films on PET. Both the ITO and the GZO films on PET with a polymeric hard coating were shown to yield properties comparable to those oof both films on glass.

Pyrolytic carbon coated silicon is prepared and employ it as an anode material for lithium secondary batteries. The pyrolytic carbon coating of silicon with sucrose precursor not only provides a suitable carbon matrix but also suppresses the breaking away of Si from the current collector during the insertion and extraction of Li+. The increase of disordered carbon content leads to the increase of discharge capacity retention. The improvements of cycle stability are attributed to a decrease in the volume change of the silicon, good networking between Si particles, and good adhesion of the current collector with the active material. The nano Si combined with the disordered carbon leads to an increase of capacity retention and initial coulombic efficiency.

Fe-36Ni alloy nanopowder was prepared via electrical explosion of wire in DI water. The nanopowder was reduced in hydrogen at 500 degrees C for 30 min. Spark plasma sintering at 800 and 1000 degrees C for 10 min was used to obtain bulk samples from the hydrogen-reduced nanopowder. The sintered samples were annealed at 500 degrees C for 2 h. X-ray diffraction was used to analyze the phases of the nanopowder and sintered samples. The results showed that the sintered samples were formed in gamma-(Fe-Ni) solid solution. The particles sizes and morphologies of the as-synthesized and hydrogen-reduced nanoparticles were observed via transmission electron microscopy. The morphologies of the as-synthesized nanoparticles had spherical core-shell structures. Core was gamma-(Fe-Ni) and the shell was FeO. The nanoparticles of the as-synthesized and hydrogen reduced samples were found to be nearly spherical in shape, with average diameters of 32 and 70 nm, respectively. The hysteresis loops of the as-synthesized nanopowder, hydrogen reduced nanopowder, and sintered samples revealed ferromagnetic characteristics.

Gold colloids were prepared by electrical explosion of wire in various media: cold water (0 degrees C), room temperature water (25 degrees C), hot water (80 degrees C), 0.01 M polysorbate surfactant 20 (TW 20) solution, mixture of 0.01 M TW 20 and 0.01 M ascorbic acid. The size distribution of nanoparticles measured by transmission electron microscope was found to shift to a smaller size with a decrease of temperature and a presence of TW 20 surfactant. The multiple light scattering results showed that medium temperature and ambient medium of explosion process is much influence on the stability of colloid. The gold colloid prepared in cold water is unstable in comparison with one prepared in warm and hot water. The best stability of gold colloid obtained with explosion medium of TW 20 and ascorbic acid solution.

Silicon (Si) has attracted tremendous attention as a high-capacity anode material for next generation Li-ion batteries (LIBs); unfortunately, it suffers from poor cyclic stability due to excessive volume expansion and reduced electrical conductivity after repeated cycles. To circumvent these issues, we propose that Si can be complexed with electrically conductive Ti2O3 to significantly enhance the reversible capacity and cyclic stability of Si-based anodes. We prepared a ternary nanocomposite of Si/Ti2O3/reduced graphene oxide (rGO) using mechanical blending and subsequent thermal reduction of the Si, TiO2 nanoparticles, and rGO nanosheets. As a result, the obtained ternary nanocomposite exhibited a specific capacity of 985 mAh/g and a Coulombic efficiency of 98.4% after 100 cycles at a current density of 100 mA/g. Furthermore, these ternary nanocomposite anodes exhibited outstanding rate capability characteristics, even with an increased current density of 10 A/g. This excellent electrochemical performance can be ascribed to the improved electron and ion transport provided by the Ti2O3 phase within the Si domains and the structurally reinforced conductive framework comprised of the rGO nanosheets. Therefore, it is expected that our approach can also be applied to other anode materials to enable large reversible capacity, excellent cyclic stability, and good rate capability for high-performance LIBs.

Proton NMR was employed to study the nematic phases upon heating and upon cooling in PCH-3 (trans-4 (4-propylcyclohexy) benzonitrile). Our systematic measurements of the nematic order parameter and spin relaxations reveal the microscopic nature of the thermal hysteresis in this relatively low molecular weight nematic liquid crystalline material. 2001 Published by Elsevier Science B.V.

KH2PO4 single crystals have been studied by employing complex impedance measurements in view of the domain freezing effect. As a result, distinct behaviors of the anisotropic domain-wall dynamics in the activation energy of domain freezing and the Vogel–Fulcher temperature before and after proton irradiation have been identified in the anisotropic crystal structure.

A homologous series of polyarylates were prepared by condensation poly- merization of three different bisphenols, isophthaloyl, and terephthaloyl chlorides (their molar ratio 5 2:1:1). The resulting polyarylates were tetramethyl bisphenol S- (TMBPS-), bisphenol S- (BPS-), and tetramethyl bisphenol A- (TMBPA-) polyary- lates, and each have structural variants; (1) methyl or no substitution on the biphenyl rings of bisphenol, and/or (2) central group connecting the biphenyl rings with or without polarity. Only the polyarylate having both methyl substitution and polar connector, i.e., TMBPS-polyarylate, was found to be compatible with PVC. The sulfone groups of TMBPS-polyarylate and chlorides of PVC exerted a dipole- dipole interaction only when the tetramethyl substitution on the bisphenol rings was present. In the absence of tetramethyl groups (BPS-polyarylate), incompatibility with PVC was ob- served. The strength of polar interactions appeared to be influenced by the methyl substitution causing electronic rearrangement in bisphenol rings. However, due to the lack of polar connector groups, the inclusion of methyl substitution in TMBPA-polyary- late was found to have no effect on the specific interactions, and hence, the compati- bility with PVC. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 2173-2180, 1998

An examination is made of the discharge and cycle life of Zr 0.5 Ti 0.5 V 0.6 Ni 1.4 alloys when a fraction (0.2 at.%) of the Ni-component is substituted by Cr or Mn. In addition, the Zr:Ti component ratios are varied to extend the cycle life of high capacity, Mn-substituted Zr 1− x Ti x V 0.6 Ni 1.2 Mn 0.2 ( x =0.0, 0.25, 0.5, 0.75) alloys. The metallurgical microstructure is observed by X-ray diffraction analysis, scanning electron microscopy, and energy dispersive X-ray analysis. Active–passive potentiodynamic behaviour, as well as charge–discharge cycle characteristics, is evaluated, and dissolved V-species in the electrolytic solution is analyzed by inductively coupled plasma spectroscopy. The corrosion behaviour of the V–Cr or the V–Mn phase in the alkaline electrolyte solution is found to determine the cycle life of an AB 2 alloy. Cr-substituted (Zr 0.5 Ti 0.5 Ni 1.2 Cr 0.2 ) alloy, containing a V–Cr phase, is estimated to involve a dissolution rate of 0.028 wt.% vanadium per cycle in an alkaline electrolytic solution, while Mn-substituted (Zr 0.5 Ti 0.5 V 0.6 Ni 1.2 Mn 0.2 ) alloy, containing a V–Mn phase, is estimated to have a dissolution rate of 0.138 wt.% vanadium per cycle. For Mn-substituted alloys, an optimum Zr:Ti ratio of 3:1, i.e., Zr 0.75 Ti 0.25 V 0.6 Ni 1.2 Mn 0.2 , is found to have the most stable cycle life. The improvement in cycle life caused by increasing the Zr content in the alloy is attributed to increase in the corrosion resistance of the alloy due to less formation of the corrosive V–Mn phase.

Although human anatomy is arranged symmetrically based on a central vertical axis, the majority of persons will use one side of their body more readily than the other. Interestingly, these lateral body dominances including ocular dominance are all rightward. The asymmetry in retinal nerve fiber layer (RNFL) thickness between the right and left eyes in healthy subjects has been reported in several studies, and the reason for this structural difference between right and left eyes is unclear. In the manuscript, we hypothesized that the characteristics of ocular dominance are reflected in the RNFL profile and may be related to inter-ocular structural differences between right and left eyes. In this study, ocular dominance occurred mostly in right eyes (right vs. left: 78.77% vs. 21.22%; P

Silicon nanowires were grown from a silane and argon gas mixture directly on a stainless steel substrate by radio-frequency plasma enhanced chemical vapor deposition (RF-PECVD) and used without any further treatment as the anode in the fabrication of lithium ion batteries. It was found that suitable pretreatment of the stainless steel substrate was required for the satisfactory growth of the silicon nanowires. In this study, the substrates were polished, etched in HF solution, coated with an aluminum catalyst layer with a thickness of c.a. 10 nm and then treated with a hydrogen plasma before the growth of the silicon nanowires. SEM (Scanning Electron Microscopy) and AFM (Atomic Force Microscopy) analyses showed that the grain size and surface roughness were increased after the hydrogen plasma pretreatment. The electrochemical performance of the silicon nanowires anode was also improved when the aluminum coated stainless steel substrate was exposed to the plasma for 20 min or longer; the initial coulombic efficiency was increased from 69.7% to 82% at a current density of 30 mA cm(-2).

A high-temperature radical scavenger, 2,2-diphenyl-l-picryl hydrazyl (DPPH), has been used to study the reaction mechanisms of polyacrylonitrile (PAN) on thermal treatment. The effect of DPPH on the cyclization reaction of PAN in both air and nitrogen, investigated by differential scanning calorimetry (DSC), helped to verify the proposed reaction mechanisms, i.e., the free radical and the ionic ones. For PAN homopolymer, the peak temperature of the reaction exotherm shifted to higher temperatures and the heat of reaction was decreased with increasing DPPH concentration. For PAN copolymer with methylacrylate and itaconic acid, however, the effects of DPPH on DSC thermograms were insignificant. The effects of IPPH suggest that the reaction of the nitrile groups proceeds by free radicals for the homopolymer while by ions for the copolymer. The activation energies for the thermal reactions of PAN in both air and nitrogen were also estimated by the dynamic DSC method, and they proved to be highly dependent on reaction mechanism, environment of thermal treatment, and DPPH concentration.

To investigate the anti-angiogenic effect of topical curcumin on corneal neovascularization in a rabbit model.One week after suturing, six eyes were treated with balanced salt solution (BSS) (group A), and six eyes were treated with curcumin 40, 80, or 160 micromol/L (groups B, C, and D, respectively), topically two times a day. After one week, light microscopy was used to analyze corneal neovascularization. The concentration of vascular endothelial growth factor (VEGF) mRNA in the corneal tissue was measured by reverse transcriptase-polymerase chain reaction (RT-PCR), and the activation of NF-kappaB was examined by immunofluorescent staining.Seven days after treatment, the sizes of the neovascularized areas were significantly reduced in groups B (50.1% +/- 6.7%), C (43.2% +/- 8.1%), and D (29.5% +/- 7.8%) compared with group A (69.5% +/- 1.5%) (p0.05). The corneal VEGF mRNA levels were significantly lower in groups C and D than they were in group A (p0.05). Immunofluorescent staining showed that phospho-NF-kappaB staining of the corneal tissue was weaker in group C than it was in groups A and B.Topical application of curcumin was useful in reducing experimental corneal neovascularization and can be used to inhibit angiogenesis in the cornea.

We have investigated the humidity and depurination (creating apurinic sites) effects on the electrical conduction in the λ-DNA films at different relative humidities and depurination times. The DNA films were found to follow the polaron hopping model, and the polaron hopping distance turned out to decrease at the higher relative humidity, more water molecules supposedly being adsorbed on the film. The activation energy showed little dependence on the depurination time at the higher relative humidity, whereas at the lower humidity it increased sharply with increasing depurination time.

PURPOSE To evaluate retinal nerve fiber layer (RNFL) thickness profiles according to the foveal position relative to the optic disc in myopia METHODS In 164 eyes of 164 healthy myopic subjects, the disc-foveal angle was defined as the angle between a horizontal line through the disc center and the line connecting the fovea and disc center in fundus photographs overlaid on Cirrus-HD optical coherence tomography (OCT) images. The quadrant/clock-hour based peripapillary RNFL thickness and differences between the inferior and superior (I-S) quadrant RNFL thicknesses were measured with OCT. RNFL thickness profiles were determined according to the disc-foveal angle and axial length (AL). RESULTS As the disc-foveal angle increased (i.e., the fovea becomes more inferior to the optic disc), the superior RNFL decreased significantly (P = 0.003), whereas the inferior RNFL and I-S difference increased (P = 0.010 and P < 0.001, respectively). As the AL increased, the average and temporal RNFLs increased significantly (P = 0.013 and P < 0.001, respectively), and I-S difference was not affected (P = 0.231). The disc-foveal angle was significantly decreased with the distance between the fovea and the optic disc (P = 0.033). In multiple linear regression analysis, the disc-foveal angle was found to be a significant factor related to I-S differences, superior and inferior RNFL (all, P < 0.05) after adjusting for age, disc area, and AL. CONCLUSIONS The intrinsic foveal position relative to the optic disc was an essential determinant of normal RNFL thickness in myopia. In particular, it was associated with the vertical asymmetry of RNFL distribution.

Microscopic environments and dynamics in LiCoO2 systems were probed by L7i nuclear magnetic relaxation measurements with regard to the structural defects as revealed by x-ray diffraction and electron spin resonance measurements. Thus, the structural defects of differing degrees, associated with Li vacancies, were well accounted for in the temperature-dependent spin-lattice relaxation rate analysis, and in the structural and dynamical inhomogeneity as derived from the relaxation patterns.