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Various quorum quenching (QQ) media have been developed to mitigate membrane biofouling in a membrane bioreactor (MBR). However, most are expensive, unstable and easily trapped in hollow fibre membranes. Here, a sol-gel method was used to develop a mesoporous silica medium entrapping a QQ bacterial strain (Rhodococcus sp. BH4). The new silica QQ medium was able to remove quorum sensing signalling molecules via both adsorption (owing to their mesoporous hydrophobic structure) and decomposition with an enzyme (lactonase), preventing MBR biofouling without affecting the water quality. It also demonstrated a relatively long life span due to its non-biodegradability and its relatively small particle size (

This study aimed to determine the correlation between the placental thickness-to-estimated foetal weight ratio on midterm ultrasonography and small-for-gestational-age (SGA) infants. In this retrospective study, the placental thickness at the umbilical cord insertion site was measured and adjusted for foetal body weight at 18-24 weeks gestation. Investigators compared the data of women who delivered SGA infants (birth weight

Currently, there is a growing emphasis on seawater desalination and wastewater reuse around the world. Reverse osmosis (RO) is typically used for both seawater desalination and wastewater reuse. As an alternative technology of RO, forward osmosis–reverse osmosis (FO–RO) hybrid system has recently attracted attention. To select suitable membrane and feed water for this process, the performance of forward osmosis (FO) membrane according to the types of membrane and feed water quality was evaluated in this study, including three types of FO membrane (membrane I/II/III) and three types of feed water (1st/2nd/3rd wastewater treatment plant effluents, WWTP Efs). Despite high structural parameter, membrane II showed the highest water permeability (5.37 LMH/bar) with highest water flux (around 27.1 LMH) using draw solution of 0.5 M NaCl (feed solution: 5 mM NaCl). In fouling test, there was severe water flux decline when 1st WWTP Ef was used as feed solution compared to the case when 2nd/3rd WWTP Efs was ...

Forward osmosis (FO) is an emerging process in water industry for wastewater treatment, water reuse, and desalination. Although many lab-scale studies have been done, the data generated cannot be directly applied to a real pilot plant due to different membrane configuration and operating conditions. In this study, we evaluated commercial spiral wound forward osmosis (SWFO) elements in various operating conditions (draw solution concentration, flow rate, and element array type). First, we investigated the SWFO special structure (winding configuration of the draw flow path). Due to the structural characteristics of SWFO, the draw flow rate showed a high-pressure drop effect because of feed flow rate. Second, we studied the performance of different element array types. Both sides of flow rate change influenced the performance of pilot-scale SWFO by reducing concentration polarization and dilution effect. In addition, according to the type of SWFO element array, the flow rate had different role in wat...

Candilis-Josic-Woods, who were active during the 1950s and 1960s, provided various ideas for achieving this. The urban complex projects of Candilis-Josic-Woods are distinguished from the pr...

Biofouling is one of the major problems in reaching the goal of being the only preferable technology for advanced wastewater treatment for membrane bioreactors (MBR). In this study, the quorum quenching mechanism (QQ) was applied to MBR technology with prevention of group behavior of micro-organisms via signaling. This study aims to prepare three different QQ immobilization media, which are (1) cell entrapping bead (CEB), (2) microbial vessel (MV), and (3) rotating microbial carrier frame (RMCF). Two different Rhodococcus sp. BH4 (QQ bacteria) amounts and three different fluxes were used to see their effects on QQ mechanism. The flux was more effective than QQ bacteria amount. Transmembrane pressure (TMP) profiles showed that all QQ products were successful in antibiofouling during MBR operation. While CEB was the most effective one, MV had the minimum influence on the TMP reduction. On the other hand, it was found out that RMCF is the most feasible one according to the cost analysis results. This study offers an idea about the potential of QQ applications in pilot-and real-scale MBR plants after examinations on different operation conditions and different QQ products.

© 2015 Balaban Desalination Publications. All rights reserved. Fouling is an inevitable phenomenon with most of the water treatment systems. Similar to RO, NF and other membrane-based systems, fouling also seriously affects the performance of low-cost forward-osmosis (FO) systems and disturbs the overall efficiency of these systems, and various cleaning practices have been evaluated to restore their designed performances. This study evaluates the performance of various physical and chemical cleaning techniques for hollow fibre forward-osmosis (HFFO) membrane. HFFO membrane was subjected to various fouling conditions using different brackish groundwater qualities and model organic foulants such as alginate, humic acid and bovine serum albumin. Results indicated that physical cleaning affects differently the flux restoration according to the type of foulants (i.e. inorganic or organic) and the crossflow rates play an important role in membrane cleaning in both membrane orientation. The higher cross flow Re values at any particular area seem important for the cleaning. With hydraulic flushing, the flux performances of HFFO were recovered fully when operated in AL-FS orientation, as high shear force helps to detach all scaling layers from the surface; however, the lower shear force did not fully restore the flux for the FS membrane in AL-DS orientation. Chemical cleaning was planned for the fouled HFFO membrane, and HCl and NaOH were used in various combination sequences. It was found that HCl did not clean the membrane used for AL-DS orientation for combined fouling. HCl cleaning (at pH 2) was found to be more effective for removing inorganic scale, whereas NaOH cleaning (at pH 11) for a similar period successfully restored the flux for all the membranes used for FS with inorganic and/or organic foulants. ethylenediamine tetra acetic acid (EDTA) was also evaluated for its cleaning performances and it was found that compared to NaOH, EDTA cleaning (1 mM concentration at pH 11) showed superior results in terms of membrane cleaning, as it helped to successfully restore the membrane flux in a very short time.

In shipbuilding, the scheduling system is susceptible to sudden changes and thus proves to be difficult to predict in advance. Computer-based simulation is commonly utilised to overcome the challenges of estimating workloads and resulting processing times. However, the main drawback of this solution is its limited applicability; in most cases, each shipyard requires a specific, customised simulation. By standardising planning data of the mid-term scheduling system, as proposed in this paper, the inefficiencies of the current model of simulation can be addressed more effectively. To present this alternative approach, this paper will begin with an analysis of the structure of complex planning data system and then proceed to construct a common structure that facilitates the simulation by converting the custom data into standardised format. This involves the development of an extensible markup language XML-based translator and the verification of developed data structure, which is carried out in net-based application.

Arterial stiffness is an independent predictor of cardiovascular disease risk. However, whether genetic risk variants are associated with arterial stiffness measures, such as pulse-wave velocity (PWV), is largely unknown. Therefore, we performed a genome-wide association study (GWAS) to identify single-nucleotide polymorphisms (SNPs) associated with PWV in a Korea population.Study participants consisted of 402 patients in the Yonsei cardiovascular genome center cohort. Arterial stiffness was measured as brachial-ankle pulse-wave velocity (baPWV). Genotyping was performed in 402 subjects with the Axiom Genome-Wide ASI 1 Array Plate containing more than 600,000 SNP markers. The findings were tested for replication in independent subjects from a community-based cohort of 1206 individuals, using a Taqman assay to include two candidate SNPs. Associations with PWV were evaluated using an additive genetic model that included age, gender, systolic blood pressure and diastolic blood pressure as covariates. GWAS and replication analyses were conducted using the measured genotype method implemented in PLINK and SAS.We observed two candidate SNPs associated with baPWV in GWAS: rs7271920 (p = 7.15 × 10(-9)) and rs10125157 (p = 8.25 × 10(-7)). However, neither of these was significant in the replication cohort.In summary, we did not identify any common genetic variants associated with baPWV in cardiovascular patients.

The aim of this study was to determine the value of additional multiple biomarkers in the prediction of premature coronary artery disease (CAD).Data from 503 CAD patients and 503 healthy control patients with matching age and sex were collected. The patient group consisted of male (25 to 55 years) and female (30 to 60 years) patients with documented angiographic multi-vessel CAD. Baseline characteristics of conventional risk factors and biomarkers were collected. We compared the conventional risk factors model with the model with six additional biomarkers (hs-CRP, IL-6, RAGE, Lp-LPA2, adiponectin, and RANTES), which have shown significant association with premature CAD. We also evaluated the effects of adding each of the six biomarkers to the conventional laboratory data. The additional biomarkers model resulted in improvements in the C-statistic (0.953 vs. 0.937, P=0.0003) in comparison with the conventional risk factors model. Among the 6 biomarkers added to the patient group, hs-CRP and IL-6 had a significant discriminative power to predict the risk of premature CAD (hs-CRP; P = 0.0005, IL-6; P= 0.003).Although conventional risk factors were more strongly associated with premature CAD than were biomarkers, adding the 6 biomarkers (hs-CRP, IL-6, RAGE, Lp-LPA2, adiponectin, and RANTES) improved the prediction of premature CAD moderately. We found that hs-CRP and IL-6 had shown a significant contribution in the prediction of premature CAD.

Diameter at breast height (DBH)-height models were developed and validated for Acacia mangium and Eucalyptus pellita species in the tree plantation of Pangkalan Bun, central Kalimantan, Indonesia, using the six commonly used nonlinear growth models. A total of 2992 and 4511 total height and DBH measurements were used for A. mangium and E. pellita species, respectively. These data were randomly split into two datasets. The majority of the data (80%) were used for the initial model development and the remaining data (20%) were applied for model validation. The combined data (100%) were used for the final model development. For model validation, the bias () for each DBH class (5 cm interval) and the overall bias were determined. The performance of the developed models were evaluated and ranked using the coefficient of determination (R2), root mean square error (RMSE), bias, absolute mean difference (AMD) and Furnival index (FI). The Weibull model had the best performance followed by the Chapman-Richards mode...

Incorporation of moving beads into membrane bioreactor (MBR) has been suggested as an effective membrane fouling control because moving beads can mechanically remove bio-cakes on the membrane surface without additional equipment and energy input. As the efficiency of fouling control is dependent on factors associated with moving beads, however, the design of experiment was applied to find optimum condition for the effective mechanical cleaning with moving beads in MBR. Bead diameter (mm), bead number, and aeration rate (m3/h) were selected as independent design parameters. Based on batch test results, the correlation between the detachment efficiency of bio-cakes and three design parameters was established using Box–Behnken methodology. When all three design parameters at their optimal conditions (beadopt) were extended to the continuous lab-scale MBR, membrane filterability increased by three times, compared with that in the control MBR without bead. On the other hand, each of five experimental s...

This study investigated the effects of onion (Allium cepa, L.) extract on the antioxidant activity of lipids in low-and high-fat-fed mouse brain lipids and its structural change during in vitro human digestion. The onion extracts were passed through an in vitro human digestion model that simulated the composition of the mouth, stomach, and small intestine juice. The brain lipids were collected from low- and high-fat-fed mouse brain and then incubated with the in vitro-digested onion extracts to determine the lipid oxidation. The results confirmed that the main phenolics of onion extract were kaempferol, myricetin, quercetin, and quercitrin. The quercetin content increased with digestion of the onion extract. Antioxidant activity was strongly influenced by in vitro human digestion of both onion extract and quercetin standard. After digestion by the small intestine, the antioxidant activity values were dramatically increased, whereas the antioxidant activity was less influenced by digestion in the stomach for both onion extract and quercetin standard. The inhibitory effect of lipid oxidation of onion extract in mouse brain lipids increased after digestion in the stomach. The inhibitory effect of lipid oxidation of onion extract was higher in the high-fat-fed mouse brain lipids than that in the low-fat-fed mouse brain lipids. The major study finding is that the antioxidative effect of onion extract may be higher in high-fat-fed mouse brain lipids than that in low-fat-fed mouse brain lipids. Thus, dietary onion may have important applications as a natural antioxidant agent in a high-fat diet.

The objective of this study was to examine the influence of stand age class (I: 0.05) among stand age classes. Both model 1 (DBH as predictor variable) and model 2 (DBH and total height as predictor variables) showed good results based on the model evaluation criteria (R 2 , RMSE and FI). The stem wood had the highest biomass distribution percentage of the three ...

Global warming has recently become a topical issue throughout the world, and the cement industry is widely seen as one of the prominent factors responsible for it. Therefore, the development of new...

A narrow pore size distribution is critical for most membrane separation processes even though it is difficult to achieve through conventional methods of membrane synthesis such as phase inversion. Although various technologies have been proposed for the preparation of isoporous membranes, few technologies are available for use in water treatment applications. In our previous works, we have prepared isoporous membranes using a novel technique based on soft lithography. A micro pattern of pyramid shape was applied to produce uniform pores. In this work, we aimed at the characterization of these isoporous membranes using both experimental and theoretical methods. The pore size distributions of the membranes were characterized by scanning electron microscopy image analysis. Using this image analysis technique, the pore size ranging from 2.2 to 21.4 μm could be identified. A simple theoretical model was developed to determine the pore size, porosity, and membrane resistance of the isoporous membranes....

Biomass expansion factors (BEFs) were developed for an age sequence (

We developed a robust method to reconstruct a digital terrain model DTM by classifying raw light detection and ranging lidar points into ground and non-ground points with the help of the Progressive Terrain Fragmentation PTF method. PTF applies iterative steps for searching terrain points by approximating terrain surfaces using the triangulated irregular network TIN model constructed from ground return points. Instead of using absolute slope or offset distance, PTF uses orthogonal distance and relative angle between a triangular plane and a node. Due to this characteristic, PTF was able to classify raw lidar points into ground and non-ground points on a heterogeneous steep forested area with a small number of parameters. We tested this approach by using a lidar data set covering a part of the Angelo Coast Range Reserve on the South Fork of the Eel River in Mendocino County, California, USA. We used systematically positioned 16 reference plots to determine the optimal parameter that can be used to separate ground and non-ground points from raw lidar point clouds. We tested at different admissible hillslope angles 15° to 20°, and the minimum total error 1.6% was acquired at the angle value of 18°. Because classifying raw lidar points into ground and non-ground points is the basis for other types of analyses, we expect that our study will provide more accurate terrain approximation and contribute to improving the extraction of other forest biophysical parameters.

The purpose of this study was to investigate the empirical properties of stock market response. The financial impact of corporate sponsorship is reflected in the market value of a firm's stock price, which is measured by comparing the abnormal stock return between the preevent window (250 trading days) and the 14 trading days of the event period. Computations of ARs, CARs, and other test statistics were based on the event study model and were carried out using the SAS 9.2 software. For the preevent windows (t = −3, t = −1), there were statistically significant positive ARs and 80% of the TOP sponsors showed positive ARs in the overall duration of the Olympic Games. The overall CARs during the event period (t = −3 through t = +10) indicates marginally positive returns for the event.

We developed a simple forest soil carbon model (Korean Forest Soil Carbon model, KFSC) requiring a small number of parameters to evaluate the forest soil carbon stocks and dynamics. The KFSC was composed of live biomass (BIO), primary dead organic matter (DOM) (AWD: aboveground woody debris; BWD: belowground woody debris; ALT: aboveground litter; and BLT: belowground litter), and secondary DOM (HUM: humus and SOC: soil organic carbon). The KFSC was validated against six Pinus densiflora forests at Gyeonggi province in central Korea and validation results showed that the model predicted the AWD, ALT, and SOC stocks with high precision (r 2=0.90–0.98, slope = 0.95–0.98). We simulated 160 years of carbon dynamics of the P. densiflora forests in Gyeonggi province (11,607 ha) under alternative clear-cut intervals that had been taking place in the past (30, 50, and 80 years). Simulated total SOC stock ranged from 298.7 to 520.5 Gg C depending on the scenario and increased with time in all scenarios. Th...

The recycling of industrial waste such as bottom ash from furnaces is an important issue in construction industry, since it enables reduction in construction cost and has beneficial effect on the environment. In this study, we have investigated the bond characteristics of steel deformed bars embedded in artificial lightweight aggregate concrete which is manufactured from bottom ash. A pullout test was performed on 144 lightweight aggregate concrete specimens to measure the bond strengths. In this test, the parameters included the compressive strength of the concrete and embedment length of rebar. The pullout load vs. slip responses and modes of failure of the specimens were identified during the test. A bond strength equation for lightweight concrete is formulated by performing a regression analysis on the test results and compared with the predictions by the existing equations such as ACI 408, Orangun’s, and Darwin’s. The comparison shows that the existing bond strength equations cannot be directly appli...

The biomass and carbon (C) storage of the main ecosystem components were examined in an age-sequence of six Japanese red pine forest stands in central Korea. The tree biomass was determined by the destructive method, and the C storage of the tree biomass, forest floor and mineral soil was estimated by analyzing the C concentration of each component. The above-ground and total tree biomass increased from 21.76 and 28.82 Mg ha−1 in the 17-year-old stand to 308.83 and 385.74 Mg ha−1 in the 73-year-old stand. The comparisons of above-ground tree and tree root biomass in replicate stands indicated that stand density has an effect on tree biomass partitioning for Japanese red pine, especially on the biomass allocation of above-ground tree and tree roots. The C concentrations were lowest in the tree roots while the highest concentrations were found in the foliage across the six Japanese red pine forest stands. The C storage in the forest floor and mineral soil were age-independent. The above-ground and total eco...

The bond behavior of reinforcing bars is an important issue in the design of reinforced concrete structures and the use of fiber reinforced polymer (FRP) rebars is a promising solution to handle the problems of steel reinforcement corrosion. This study investigates the bond characteristics of carbon and aramid FRP (CFRP and AFRP) bars embedded in normal strength concrete. A pullout test was performed on 63 normal strength concrete specimens reinforced with FRP and steel rebars with different embedment lengths and bar diameters. The average bond stress versus slip curve is plotted for all specimens and their failure modes are identified. The effects of the embedment length and diameter of an FRP rebar on its bond strength are examined in this work. The bond strengths obtained from the test results are compared with the predictions by the bond strength equation proposed by Okelo and Yuan (2005), and its validity is evaluated.

The purpose of this study was to examine the theoretical relationship between service quality in a sport event, perceived value (PV), destination image, and behavioral intention (BI). This study surveyed 451 spectators who attended the Tour de Korea, an international road bicycling stage race. A series of a structural equation model tests were performed to examine the relationships among the variables. The mediating effect of the destination image was also examined. The results suggest that service quality positively influenced PV, destination image, and BI; PV positively influenced the destination image, but negatively influenced BI; and the destination image plays an important mediating role in the relationship between service quality and BI and the relationship between PV and destination image. To date, only a few empirical studies have examined the theoretical relationship between destination image, service quality, and PV. Particularly, the potential mediating role of the destination image in this re...

The purpose of this study was to (1) examine the theoretical relationships between trust, mental skills associated with athletic performance (MSAP), and athlete satisfaction in the context of a gambling-legal bicycle racing business, and (2) provide bicycle racing managers with information and recommendations for improving athlete's satisfaction and retention. A structural equation model test with maximum likelihood estimation was employed to test the relationships among the research variables. In addition, the mediating effect of MSAP on the relationship between trust and athlete satisfaction was examined. Survey data from 328 bicycle racing athletes suggested that trust between constituents has a positive influence on both the MSAP and athlete satisfaction; MSAP has a positive influence on athlete satisfaction; and the MSAP mediates the relationship between trust and athlete satisfaction. The results of this study provide a scholarly contribution to the literature and provide managers with meaningful ma...

The purpose of this study was to examine the differences of athletes' trust, mental skills associated with athletic performance, and satisfaction in a gambling-legal cycle racing business. A multivariate analysis of variance, using 328 professional racing cyclists in South Korea, showed older athletes (over 40 years old) rated cognition-based trust the highest. The shorter career athletes (1–3 years) rated affect-based trust and mental skills the highest, while a longer career (over 7 years) and the highest class of racing cyclists rated cognitive skills the lowest. The results also suggested that younger athletes (20–29 years old) have higher levels of social satisfaction than older athletes. In addition, athletes with shorter careers rated social and task satisfaction the highest. Finally, we found that longer career athletes had the lowest levels of trust, mental skills, and athlete satisfaction. The results may assist administrators to better understand the important issues of managing athlet...

The purpose of this study was to examine the influence of consumers’ service quality perceptions on satisfaction, revisit intention and the role of gender in the context of high profile golf club business. Specifically, the researchers investigated (1) the role of gender in predicting their service quality perceptions and (2) the relationship between quality perceptions and satisfaction and intention. A total of 528 golf club members participated in the study. Seventy one percent of the respondents (n = 375) were male while twenty nine percent of the respondents were female golfers (n = 153). Results showed that Tangibles and Empathy were critical service quality dimensions for determining satisfaction of both male and female golfers. Female golfers tended to pay more attention to physical representations, cleanliness and appearance of service encounters. The findings of this study may suggest meaningful implications (e.g., developing market segmentation and promotional strategies) for managers in the golf industry.

In this paper, light‐emitting‐diode (LED) backlight driving circuits and dimming method for medium‐sized and large liquid crystal displays (LCDs) are proposed. The double loop control method, the intelligent‐phase‐shifted PWM dimming method, the fast‐switching current regulator, and the current matching techniques are proposed to improve not only the current regulation characteristics and the power efficiency but also the current matching characteristics and the transient response of the LED current. The brightness of the backlight using the proposed local dimming method was determined from the histogram of the local block to reduce the power consumption of the backlight without image distortion. The measured maximum power efficiency of the LED backlight driving circuit for medium‐sized LCDs was 90%, and the simulation results showed an 88% maximum power efficiency of the LED backlight driving circuit for large LCDs. The maximum backlight power‐saving ratio of the proposed dimming method was 41.7...

The effect of powdered activated carbon (PAC) addition on the architecture and cohesion strength of bio-cake in a membrane bioreactor (MBR) was investigated. Two reactors, a conventional MBR and a membrane-coupled biological activated carbon reactor (MBR ac ), were run in parallel. The addition of PAC led to a substantial increase in membrane permeability. Based on the conventional filtration theory, microbial floc size (d), bio-cake porosity (∊), and total attached biomass (TAB) were determined to find the key mechanism for the enhanced permeability. Unexpectedly the addition of PAC did not significantly change either the microbial floc size (d) or the porosity (∊) of the bio-cake. It decreased, however, not only the concentration of extra-cellular polymeric substances (EPS) in the bulk phase but also the TAB on the membrane. Using a separate batch cohesion test, it was revealed that the cohesion strength between microorganisms in the bio-cake in the MBR ac was weaker than that in the MBR. The addition o...

A parameter calibration of activated sludge models (ASMs) was performed to predict effluent chemical oxygen demand (COD), total nitrogen (TN), total phosphate (TP) and total suspended solid (TSS) concentrations of the enhanced biological phosphate removal process. Such calibration is an essential process for simulating the behavior of real-world wastewater treatment processes properly. Six different simulations were attempted to develop a reliable calibration method using two different parameter estimation methods for three objective functions. For the parameter estimation method, dynamic parameter estimation (DPE) and static parameter estimation (SPE) were investigated. The objective functions were based on the effluent quality (EQ) index of benchmark simulation and the effluent quality standards (EQS) in Korea. When using the same parameter estimation method, the predicted errors with the EQS-based objective functions could be decreased by approximately 20% over EQ index-based functions for TSS. When us...

The Clean Development Mechanism (CDM) under the Kyoto Protocol has expedited various global warming mitigation opportunities that allow Bangladesh to receive investments from those Annex I countries wishing to offset their emissions of greenhouse gases. Bangladesh has a special interest in strategies for combating global warming because its large areas that need to be planted represent a potentially large carbon sink, and at the same time its high rate of deforestation represents a huge carbon source. To properly assign carbon credits within the forestry sector of Bangladesh, a number of important issues and uncertainties need to be examined and resolved. Afforestation and reforestation (A/R) offers opportunities for carbon credits, which is subject to the end-use of the forest products. A/R may be the best option, as well as conserving the existing carbon sink offered by Bangladesh for mitigating global warming. This article discusses the legal issues raised in combating global warming; the potential of ...

For estimation of tree parameters at the single-tree level using light detection and ranging (LiDAR), detection and delineation of individual trees is an important starting point. This paper presents an approach for delineating individual trees and estimating tree heights using LiDAR in coniferous (Pinus koraiensis, Larix leptolepis) and deciduous (Quercus spp.) forests in South Korea. To detect tree tops, the extended maxima transformation of morphological image-analysis methods was applied to the digital canopy model (DCM). In order to monitor spurious local maxima in the DCM, which cause false tree tops, different h values in the extended maxima transformation were explored. For delineation of individual trees, watershed segmentation was applied to the distance-transformed image from the detected tree tops. The tree heights were extracted using the maximum value within the segmented crown boundary. Thereafter, individual tree data estimated by LiDAR were compared to the field measurement data under five categories (correct delineation, satisfied delineation, merged tree, split tree, and not found). In our study, P. koraiensis, L. leptolepis, and Quercus spp. had the best detection accuracies of 68.1% at h = 0.18, 86.7% at h = 0.12, and 67.4% at h = 0.02, respectively. The coefficients of determination for tree height estimation were 0.77, 0.80, and 0.74 for P. koraiensis, L. leptolepis, and Quercus spp., respectively.

The diffusion and surface oxidation rates of Fe deposited on Si and barrier layers of Al/SiO2 and Al2O3/SiO2 have been comparatively studied and correlated with the growth of carbon nanotubes (CNTs). Initially, Fe/Si, Fe/Al/SiO2/Si and Fe/Al2O3/SiO2/Si samples were subjected to thermal chemical vapour deposition (CVD) at ∼650°C for ∼30 min to grow the CNTs. Scanning electron microscopy analysis showed that the height of the CNTs on the Fe/Al2O3/SiO2/Si samples was relatively high (∼9.5–11 µm), as compared with the other samples. To investigate this, a few as-prepared samples were thermally annealed at ∼650°C for ∼30 min and characterized by dynamic secondary ion mass spectroscopy (D-SIMS) and X-ray photoelectron spectroscopy (XPS). The D-SIMS results showed that the diffusion depth, x Fe, and magnitude of the diffusivity, D Fe, of the Fe atoms are highest for the Fe/Si sample. This is attributed to vacancy-mediated migration, which leads to the formation of unstable, non-stoichiometric Fe–Si and Fe–O–Si p...

To evaluate the biocompatibility of nanocomposites used for artificial conjunctiva.Fifty New Zealand white rabbits were used for the experiments. Nanocomposites of poly -caprolactone (PCL) and of PCL coated with polyvinyl alcohol (PCL+PVA), polyvinyl pyrrolidone (PCL+PVP), or chitosan (PCL+C), and amniotic membrane (AM) as a control, were cut into small disks with a diameter of 3.5 mm. The disks were inserted underneath the conjunctiva to measure their inflammation-inducing properties. To investigate epithelial adhesion and goblet cell differentiation, the disks were transplanted after round conjunctival excision. Cultivated conjunctival epithelial cells on nanocomposite were then transplanted onto the abdomen of Balb/c athymic mice. The number of inflammatory cells and the density of goblet cells were measured using hematoxylin and eosin, periodic-acid-Schiff, and immunohistochemistry after 2 weeks.The number of inflammatory cells found inside of the inserts was as follows: 21 +/- 4.9 for controls, 21 +/- 15.1 for PCL, 49.6 +/- 26.0 for PCL+PVP, 40.2 +/- 17.1 for PCL+C, and 13.8 +/- 3.9 for PCL+PVA. In PCL+PVA, the accumulation of inflammatory cells was significantly lower than in the controls (p0.01, Mann-Whitney U). The reepithelialization of conjunctival cells was accomplished in more than 75% of all disks except for the PCL+C. In addition, we found the differentiation of goblet cells in the following order from greatest to least: amniotic membrane, PCL, and PCL+PVP.Nanocomposites of PCL were biocompatible in rabbit conjunctiva, suggesting that PCL may be considered as a candidate for use in the development of artificial conjunctiva.

By the voltage threshold (Vt) close‐curve measurement method, the changes in the discharge characteristics such as a firing voltage and IR emission among the three electrodes were examined relative to the low or high panel temperature ranging from ‐10 to 80°. The variation in the panel temperature was found significantly influence the surface discharge between the MgO surfaces rather than the plate gap discharge between the MgO and phosphor layers. Based on this experimental observation, a modified reset waveform that alleviates the surface discharge during a ramp‐up and ‐down period was deeloped. By adopting the proposed reset waveform, a stable address discharge could be obtained irrespective of the panel temperature variation.

The efficiency of pretreatment using microfiltration (MF) and ultrafiltration (UF) was investigated in surface water nanofiltration for drinking water production. A series of pretreatments prior to NF were performed to examine their efficiency to improve NF flux. Based on lab‐scale nanofiltration experiments, the major foulants appeared to be colloidal particles rather than dissolved organic matter for surface water containing hydrophilic organics. During the NF operations, changes in particle size by MF/UF pretreatment were found to be the reason for different pretreatment efficiencies with the pore size of prefilters. NF flux and pretreatment efficiency were quantitatively interpreted using a theoretical approach based on the particle back‐transport model. Considering the energy consumption to produce unit volume of NF permeate, optimum pretreatment conditions were suggested.

In this study, a model equation was derived for a submerged, hollow‐fiber microfiltration (MF) membrane under constant flux. The validity of model equation was examined in two aspects: different feed water concentration and membrane pore size. When the concentration of starch solution (feed water) was varied from 1.5 to 9.0 g/L, the model equation predicted transmembrane pressure (TMP) variation at the precision of 99% within that range of concentration. In the cases of a different nominal membrane pore size (0.1 and 0.4 µm), it was capable of predicting TMP variation in a good manner. From experimental TMP data, it was ascertained that different pore sizes of membrane hardly affected filtration time. At the same time, TMP, flux, and total resistance distributions along the membrane length, which cannot be measured directly, could be calculated using the model equation.

The system was designed to use Poloxamer as a vehicle for ophthalmic drug delivery using in situ gel formation property. To enhance the wound healing and cell adhesion as well as transparency of Poloxamer hydrogel, chondroitin 6-sulfate (C6S) was introduced into Poloxamer. For this purpose, mono amine-terminated Poloxamer (MATP), which was end-capped with ethylene amine group only in one side of terminal hydroxyl groups of Poloxamer, was synthesized. Subsequently, C6S-graft-Poloxamer copolymer (C6S-g-Poloxamer) was prepared by reaction between the amine groups of MATP and carboxyl groups of C6S in the presence of 1-ethyl-3-(3-dimethylaminopropyl)-carboimide (EDC). The coupling of MATP with C6S was clarified by 1H-NMR and FT-IR spectroscopy. The gelation temperature of graft copolymers was determined by measuring the temperature at which immobility of the meniscus in each solution was first noted. Release behavior of ciprofloxacin from C6S-g-Poloxamer hydrogel in vitro was investigated as a function of C6S content in the graft copolymer by a spectrophotometric assay at 287 nm using an UV spectrophotometer. Differences in the adhesion and morphology of human lens cell between Poloxamer- and C6S-g-Poloxamer-coated surfaces were also investigated. The gelation temperatures of C6S-g-Poloxamer copolymers were lowered with increasing of the concentration of the copolymer and decreasing of C6S content. The release of ciprofloxacin from the graft copolymer was sustained compared with Poloxamer itself and decreased with increasing the content of C6S in the copolymer due to the in situ gel formation of the copolymer and viscous properties of C6S. Human lens cells (B3) adhered to C6S-g-Poloxamer-coated surface were observed as transformed shapes after 2 days. The bioadhesive and thermally gelling of these graft copolymers will be expected to be an excellent drug carrier for the prolonged delivery to surface of the eye.

To investigate adhesion complex formation in cultivated human limbal epithelium after transplantation into the limbal deficient model.Cultivated epithelium on amniotic membrane was transplanted into limbal deficient rabbits. The transplanted rabbits and the controls were sacrificed at 1, 2, 3, and 4 weeks. The adhesion complex was examined by electron microscopy and immunohistochemistry.Morphologically identifiable hemidesmosomes appeared at 1 week, and matured adhesion complex was found at 3 weeks. Collagen VII was partly stained after transplantation. The mean numbers of hemidesmosomes/2.25 microm were 2.3 +/- 0.9, 2.5 +/- 0.5, 5.2 +/- 1.0, and 4.0 +/- 0.9 at 1, 2, 3, and 4 weeks, and all they were smaller than those in the control, respectively (p0.05). It reached 137.4% of the density of hemidesmosomes in human cornea at 3 weeks. The average depths of anchoring fibril were 0.10 +/- 0.03, 0.27 +/- 0.06, 0.45 +/- 0.06, and 0.46 +/- 0.12 microm at 1, 2, 3, and 4 weeks, reaching 75.0% of that in the human cornea after 3 weeks, although they were shallower than that of the control, respectively (p0.05).Assembly of adhesion complex in cultivated epithelium transplanted in limbal deficient rabbit might recover to the level of that in the human after 3 weeks, although it was delayed compared with that in normal wound healing of the rabbit.

Fully integrated film bulk acoustic resonators and band pass filters using a bulk micromachining method have been designed, fabricated, and characterized. Aluminum nitride (AlN) has been used for a piezoelectric material and Molybdenum (Mo) was employed as top and bottom electrodes. Also, Ti seed layers were used in order to obtain highly c-axis oriented AlN piezoelectric films. The film bulk acoustic resonators fabricated with highly c-axis oriented AlN films showed good performances such as an effective mechanical coupling coefficient of 7.5% and a quality factor of 1530. The band pass filter consisted of seven film bulk acoustic resonators with a high quality factor exhibited a transmission loss of −3.2 dB, a ripple of 1.2 dB in pass band, and attenuation values of −38 dB and −49 dB at both band boundaries, respectively.

BACKGROUND: Dandruff is a chronic scalp condition characterized by scaling. The common causative agent is now accepted to be the lipophilic yeast Malassezia furfur. Ketoconazole, a highly effective antifungal agent against M. furfur has been used for the treatment of dandruff.AIM: To determine whether a 1.5% ciclopirox olamine shampoo is as effective as a 2% ketoconazole shampoo for the treatment of mild to moderate dandruff.METHODS: A total of 64 patients, with mild to moderate dandruff, participated in the study. The study consisted of three consecutive phases: a 2‐week washout period, a 4‐week treatment period and a 2‐week post‐treatment period. Patients were randomized equally to either the 1.5% ciclopirox olamine shampoo or 2% ketoconazole shampoo. An overall dandruff score was calculated using an area of dandruff involvement score and a severity score. Patients evaluated the presence of pruritus and also reported a global evaluation of efficacy.RESULTS: In all, 57 patients successfully completed all...

A flake graphite cast iron was produced to determine the effect of rare earth (RE) additions on the microstructure and chilling tendency of low (0.01–0.03%S) and high (0.03–0.1%S) sulfur level cont...

In order to increase hydrophilicity and thereby to reduce membrane fouling caused by hydrophobic adsorption, the surface of a hydrophobic 0.2 microm polypropylene (PP) membrane was modified by ozone treatment followed by graft polymerization with 2-hydroxy-ethyl methacrylate (HEMA). The modified PP (MPP) membranes were characterized in terms of contact angle, morphology and degree of grafting (DG). The contact angle was reduced from 112 degrees for a PP membrane to nearly 0 degrees for MPP membranes by introducing functional groups such as hydroxyl (-OH) and carbonyl groups (C=O) on the membrane surface. As the DG increased, the O/C ratio and membrane resistance of the MPP membrane increased. Using the MPP membrane in the crossflow operation of an anaerobic membrane bioreactor (MBR), the membrane permeability was enhanced although it was largely dependent on the DG of MPP.

The effect of ozonation on membrane flux and water quality was investigated in an ozonation ultrafiltration (UF) hybrid system. Crossflow UF was performed in total recycle mode to study the effect of ozonation on membrane fouling and disinfection by-product formation potentials of organics. Total organic carbon (TOC), UV absorbance at 254 ran (UV254) and trihalomethane formation potential (THMFP) were measured as water quality parameters. The effect of ozonation on membrane flux was found to be largely dependent on raw water quality as well as ozone dose. In case of upstream water (A), preozonation achieved significant flux enhancement regardless of ozone dose. Whereas, for the downstream water (B), the steady state flux was increased or decreased depending on ozone dose. The analysis based on the resistance-in-series model provided the mechanistic interpretation on the membrane flux variation. Ozonation in an ozone-ultrafiltration system always brought about a decrease in cake resistance (Rc) an...

The effect of powdered activated carbon (PAC) addition on the performance of a membrane-coupled anaerobic bioreactor (MCAB) was investigated in terms of membrane filterability and treatabilty through a series of batch and continuous microfiltration (MF) experiments. In both batch and continuous MF of the digestion broth, a flux improvement with PAC addition was achieved, especially when a higher shear rate and/or a higher PAC dose were applied. Both the fouling and cake layer resistances decreased continuously with increasing the PAC dose up to 5 g/L. PAC played an important role in subtantially reducing the biomass cake resistance due to its incompressible nature and higher backtransport velocities. PAC might have a scouring effect for removing the deposited biomass cake from the membrane surface while sorbing and/or coagulating dissolved organics and colloidal particles in the broth. The chemical oxygen demand and color in the effluent were much removed with PAC addition, and the system was also more st...

The fouling mechanism of an inorganic membrane was studied during the operation of a membrane-coupled anaerobic bioreactor (MCAB) when alcohol distillery wastewater was used as a digester feed. It was observed that the fouling mechanism of an inorganic membrane was significantly different from that of conventional membrane filtration processes. The main foulant was identified to be an inorganic precipitate, struvite (MgNH4PO4·6H2O), rather than anaerobic microbial floes. Struvite appears to be precipitated not only on the membrane surface but also inside the membrane pores. The amount of struvite generated during the bioreaction was estimated to be about 2g/L alcohol distillery wastewater. The inorganic foulant was not easily removed by general physical cleaning such as depressurization, lumen flushing, and backflushing. Based on these findings, the membrane fouling was alleviated and thus flux was enhanced by adopting a “backfeeding” mode which has dual purpose of feeding and backflushing with p...