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Many heterologous proteins can be secreted by bacterial ATP-binding cassette (ABC) transporters, provided that they are fused with the C-terminal signal sequence, but some proteins are not secretable even though they carry the right signal sequence. The invention of a method to secrete these non-secretable proteins would be valuable both for understanding the secretory physiology of ABC transporters and for industrial applications. Herein, we postulate that cationic “supercharged” regions within the target substrate protein block the secretion by ABC transporters. We also suggest that the secretion of such substrate proteins can be rescued by neutralizing those cationic supercharged regions via structure-preserving point mutageneses. Surface-protruding, non-structural cationic amino acids within the cationic supercharged regions were replaced by anionic or neutral hydrophilic amino acids, reducing the cationic charge density. The examples of rescued secretions we provide include the spike protein of SARS-CoV-2, glutathione-S-transferase, streptavidin, lipase, tyrosinase, cutinase, growth factors, etc. In summary, our study provides a method to predict the secretability and a tool to rescue the secretion by correcting the secretion-blocking regions, making a significant step in understanding the physiological properties of ABC transporter-dependent protein secretion and laying the foundation for the development of a secretion-based protein-producing platform.

Sophorolipids (SLs) from Candida batistae has a unique structure that contains ω-hydroxy fatty acids, which can be used as a building block in the polymer and fragrance industries. To improve the production of this industrially important SLs, we optimized the culture medium of C. batistae for the first time. Using an optimized culture medium composed of 50 g/L glucose, 50 g/L rapeseed oil, 5 g/L ammonium nitrate and 5 g/L yeast extract, SLs were produced at a concentration of 24.1 g/L in a flask culture. Sophorolipids production increased by about 19% (28.6 g/L) in a fed-batch fermentation using a 5 L fermentor. Sophorolipids production more increased by about 121% (53.2 g/L), compared with that in a flask culture, in a fed-batch fermentation using a 50 L fermentor, which was about 787% higher than that of the previously reported SLs production (6 g/L). These results indicate that a significant increase in C. batistae-derived SLs production can be achieved by optimization of the culture medium composition and fed-batch fermentation. Finally, we successfully separated and purified the SLs from the culture medium. The improved production of SLs from C. batistae in this study will help facilitate the successful development of applications for the SLs.

Background: Sports-related injuries are the most common in the lower extremities among physical regions, and overall injury rates were higher among males and persons aged 5–24 years. To evaluate impaired functional performance in sports training facilities and sports, a marker-less motion analysis system that can measure joint kinematics in bright indoor and outdoor environments is required. Objective: To establish the concurrent and angle-trajectory validity and intra-trial reliability of a novel multi-view image-based motion analysis system with marker-less during lower extremity tasks in healthy young men.Methods: Ten healthy young men participated voluntarily in this study. The hip and knee joint angles were collected using a multi-view image-based motion analysis system (marker-less) and a Vicon motion capture system (with markers) during the lower extremity tasks. Intraclass correlation coefficient (ICC) analyses were used to identify the concurrent and angle-trajectory validity and intra-trial reliability of the multi-view image-based motion analysis system.Results: In the concurrent validity, the correlation analysis revealed that the ICC3, k values on the hip and knee flexions during knee bending in sitting, standing, and squat movements were 0.747 to 0.936 between the two systems. In particular, the angle-trajectory validity was very high (ICC3, 1 = 0.859–0.998), indicating a high agreement between the two systems. The intra-trial reliability of each system was excellent (ICC3, 1 = 0.773–0.974), reflecting high reproducibility. Conclusion: We suggest that this novel marker-less motion analysis system is highly accurate and reliable for measuring joint kinematics of the lower extremities during the rehabilitation process and monitoring the sports performance of athletes in sports training facilities.

Bacteria have evolved a diverse range of secretion systems to export different substrates across their cell envelope. Although secretion of proteins into the extracellular space could offer advantages for recombinant protein production, the low secretion titers of the secretion systems for some heterologous proteins remain a clear drawback of their utility at commercial scales. Therefore, a potential use of most of secretion systems as production platforms at large scales are still limited. To overcome this limitation, remarkable efforts have been made toward improving the secretion efficiency of different bacterial secretion systems in recent years. Here, we review the progress with respect to biotechnological applications of type I secretion system (T1SS) of Gram-negative bacteria. We will also focus on the applicability of T1SS for the secretion of heterologous proteins as well as vaccine development. Last but not least, we explore the employed engineering strategies that have enhanced the secretion efficiencies of T1SS. Attention is also paid to directed evolution approaches that may offer a more versatile approach to optimize secretion efficiency of T1SS.

Pseudomonas fluorescens, a gram-negative bacterium, has been proven to be a capable protein manufacturing factory (PMF). Utilizing its ATP-binding cassette (ABC) transporter, a type I secretion system, P. fluorescens has successfully produced recombinant proteins. However, besides the target proteins, P. fluorescens also secretes unnecessary background proteins that complicate protein purification and other downstream processes. One of the background proteins produced in large amounts is FliC, a flagellin protein. In this study, the master regulator of flagella gene expression, fleQ, was deleted from P. fluorescens&nbsp, Δtp, a lipase and protease double-deletion mutant, via targeted gene knockout. FleQ directs flagella synthesis, so the new strain, P. fluorescens&nbsp, ΔfleQ, does not produce flagella-related proteins. This not only simplifies purification but also makes P. fluorescens ΔfleQ an eco-friendly expression host because it will not survive outside a controlled environment. Six recombinant growth factors, namely, insulin-like growth factors I and II, beta-nerve growth factor, fibroblast growth factor 1, transforming growth factor beta, and tumor necrosis factor beta, prepared using our supercharging method, were successfully secreted by P. fluorescens ΔfleQ. Our findings demonstrate the potential of P. fluorescens ΔfleQ, combined with our supercharging process, as a PMF.

In this paper, a novel online cell screening algorithm is proposed to estimate the available maximum current considering the inconsistencies of the hundreds of cells in the battery pack for electric vehicles. The available maximum current is defined based on the allowable terminal voltage, and the inconsistency parameters which affect the maximum available current are analyzed. The proposed algorithm screens the small number of candidates of which terminal voltages first exceed the allowable range by comprehensively comparing the inconsistency parameters. The proposed algorithm uses just the comparison operation for the parameters basically measured and estimated from the battery management system, which can reduce the computational burden significantly. The proposed algorithm is validated by experiments conducted on a nickel manganese cobalt oxide-type battery pack commercially manufactured for electric vehicles.

Bacterial phospholipase A1 (PLA1) is used in various industrial fields because it can catalyze the hydrolysis, esterification, and transesterification of phospholipids to their functional derivatives. It also has a role in the degumming process of crude plant oils. However, bacterial expression of the foreign PLA1-encoding gene was generally hampered because intracellularly expressed PLA1 is inherently toxic and damages the phospholipid membrane. In this study, we report that secretion-based production of recombinant PlaA, a bacterial PLA1 gene, or co-expression of PlaS, an accessory gene, minimizes this harmful effect. We were able to achieve high-level PlaA production via secretion-based protein production. Here, TliD/TliE/TliF, an ABC transporter complex of Pseudomonas fluorescens SIK-W1, was used to secrete recombinant proteins to the extracellular medium. In order to control the protein expression with induction, a new strain of P. fluorescens, which had the lac operon repressor gene lacI, was constructed and named ZYAI strain. The bacteriotoxic PlaA protein was successfully produced in a bacterial host, with help from ABC transporter-mediated secretion, induction-controlled protein expression, and fermentation. The final protein product is capable of degumming oil efficiently, signifying its application potential.

Herein, performance degradation of pouch type of 20 A h lithium ion battery from electric bus is clarified after a classification using the resistance value from A to D grade. The obtained cells are carefully disassembled to produce cathode, anode, and separator. Scanning electron microscopy and energy dispersive spectroscopy analysis reveal that morphological change of electrode mostly occur in the anodes surface in D-grade cells, while cathodes of all the grades mostly remain similar. Although the change of crystalline structure of all electrodes is negligible, a growth of solid-electrolyte interphase film mostly happen in the D-grade anodes, which is confirmed by X-ray photoelectron spectroscopy analysis. Furthermore, the degradation of cycle and rate performance happen in the anode of D-grade cells, whereas the cathodes remain invariant irrespective of grade. Furthermore, the disassembled separators exhibit that the Gurley number of separators is commonly increased in the used cells.

Efficient protein production for industrial and academic purposes often involves engineering microorganisms to produce and secrete target proteins into the culture. Pseudomonas fluorescens has a TliDEF ATP-binding cassette transporter, a type I secretion system, which recognizes C-terminal LARD3 signal sequence of thermostable lipase TliA. Many proteins are secreted by TliDEF in vivo when recombined with LARD3, but there are still others that cannot be secreted by TliDEF even when LARD3 is attached. However, the factors that determine whether or not a recombinant protein can be secreted through TliDEF are still unknown. Here, we recombined LARD3 with several proteins and examined their secretion through TliDEF. We found that the proteins secreted via LARD3 are highly negatively charged with highly-acidic isoelectric points (pI) lower than 5.5. Attaching oligo-aspartate to lower the pI of negatively-charged recombinant proteins improved their secretion, and attaching oligo-arginine to negatively-charged proteins blocked their secretion by LARD3. In addition, negatively supercharged green fluorescent protein (GFP) showed improved secretion, whereas positively supercharged GFP did not secrete. These results disclosed that proteins' acidic pI and net negative charge are major factors that determine their secretion through TliDEF. Homology modeling for TliDEF revealed that TliD dimer forms evolutionarily-conserved positively-charged clusters in its pore and substrate entrance site, which also partially explains the pI dependence of the TliDEF-dependent secretions. In conclusion, lowering the isoelectric point improved LARD3-mediated protein secretion, both widening the range of protein targets for efficient production via secretion and signifying an important aspect of ABC transporter–mediated secretions.

Although mucoactive proteins, such as epidermal growth factor (EGF), could improve clinical outcomes of intestinal ulcerative diseases, their gastrointestinal application is limited because of their proteolytic digestion or concerns about tumor promotion. In the present study, ATP-binding cassette (ABC) transporter-linked secretion of human EGF from probiotic Escherichia coli (EGF-EcN) was created to promote beneficial actions of the EGF receptor, which is notably attenuated in patients with intestinal ulcerative injuries. Preventive and postinjury treatment with EGF-EcN alleviated intestinal ulcers and other readouts of disease severity in murine intestinal ulcer models. EGF-EcN administration promoted the restitutive recovery of damaged epithelial layers, particularly via upward expansion of highly proliferating progenitor cells from the lower crypts. Along with the epithelial barrier benefit, EGF-EcN improved goblet cell-associated mucosal integrity, which controls the access of luminal microbiota to the underlying host tissues. Despite concern about the oncogenic action of EGF, EGF-EcN did not aggravate colitis-associated colon cancer; instead, it alleviated protumorigenic activities and improved barrier integrity in the lesions. All findings indicate that probiotic bacteria-based precision delivery of human EGF is a promising mucosal intervention against gastrointestinal ulcers and malignant distress through crypt-derived barrier restoration.

Tyrosinase is a monooxygenase that catalyzes both the hydroxylation of p-hydroxyphenyl moieties to o-catechols and the oxidation of o-catechols to o-quinones. Apart from its critical functionality in melanogenesis and the synthesis of various neurotransmitters, this enzyme is also used in a variety of biotechnological applications, most notably mediating covalent cross-linking between polymers containing p-hydroxyphenyl groups, forming a hydrogel. Tyrosinases from the genus Streptomyces are usually secreted as a complex with their caddie protein. In this study, we report an increased secretion efficiency observed when the Streptomyces antibioticus tyrosinase gene melC2 was introduced into Pseudomonas fluorescens along with its caddie protein gene melC1, which has the DNA sequence for the Tat (twin-arginine translocation) signal. IMPORTANCE We observed that the S. antibioticus extracellular tyrosinase secretion level was even higher in its nonnatural translationally conjugated fusion protein form than in the natural complex of two separated polypeptides. The results of this study demonstrate that tyrosinase-expressing P. fluorescens can be a stable source of bacterial tyrosinase through exploiting the secretory machinery of P. fluorescens.

This paper proposes an improved high voltage dc-dc converter with a partial-resonant network (partial- resonant HDC) to be used in electric vehicle applications for enhanced efficiency and power density. In order to achieve enhanced performance compared to the conventional HDC, an approach for the optimal switching frequency is conducted by considering the trade-off between the efficiency and power density. Furthermore, an optimization of the partial-resonant network which enables the designer to place more emphasis on either the efficiency or the power density is concerned. The validity of the partial-resonant HDC performance is verified through the experimental results of the manufactured HDC under the 13.3 kW load condition, and the efficiency is enhanced by 0.73% maximally, and the power density is improved by 14.23%.

In this paper, a mixed algorithm is proposed to overcome the limitations of the conventional algorithms, which cannot be applied in various driving patterns of drivers. The proposed algorithm based on the coulomb counting method is mixed with reset algorithms that consist of the enhanced OCV reset method and the DCIR iterative calculation method. It has many advantages, such as a simple model structure, low computational overload in various profiles, and a low accumulated SOC error through the frequent SOC reset. In addition, the enhanced parameter based on a mathematical analysis of the second-order RC ladder model is calculated and is then applied to all of the methods. The proposed algorithm is verified by experimental results based on a 27-Ah LiPB. It is observed that the SOC RMSE of the proposed algorithm decreases by about 9.16% compared to the coulomb counting method.

This paper proposes the optimization method and the control algorithm for hybrid battery energy storage system (HBESS) by combination of the high energy battery and high power battery. The proposed design method minimizes the total number of the batteries through the cost function. The control algorithm for high efficiency is composed of fuzzy logic controller (FLC) so as to reflect the various control conditions and the dynamic characteristics of battery. Finally, the proposed design method and algorithm are validated through informative simulation based on experimental results.

Background Despite growing evidence regarding the role of osteopathic manipulative treatment (OMT) for the management of low back pain, there is little evidence to support the use of OMT as a post-operative rehabilitation to improve the functional outcomes of lumbar disc surgery. Objective To assess the feasibility for a future definitive randomised control trial that would indicate whether OMT improves post-operative outcomes after lumbar microdiscectomy compared to a standard exercise programme. Design Randomised controlled pilot study. Setting Department of Spinal Surgery and Department of Spinal Rehabilitation at a major metropolitan spine surgery hospital, Seoul, South Korea. Methods Patients who underwent lumbar microdiscectomy due to low back pain with referred leg pain resulting from a herniated disc were enrolled in the study. Thirty-three patients aged 25–65 years were randomly assigned using a random number table to the OMT ( n = 16) group or exercise group ( n = 17). Patients received the allocated intervention twice a week for 4 weeks. Each session was 30 min. Primary outcomes were post-surgical functional disability and intensity of low back and leg pain. Outcome measures were assessed at baseline (2–3 weeks after surgery) and post-intervention (7–8 weeks after surgery). Double blinding was not feasible in the study setting. Results Thirty-three participants were analysed. Both rehabilitation interventions improved all primary and secondary outcomes. Post-surgical physical disability improved more with OMT rehabilitation than the exercise programme (54% vs. 26%, P Conclusion The current pilot study shows the feasibility of a future definitive randomised control trial investigating whether rehabilitation with OMT is a viable approach for post-operative management of a lumbar microdiscectomy.

In this paper, a single-switch ZVZCS quasi-resonant CLL isolated DC-DC converter for driving a low-power (less than 100 W) 32"" LED backlighting liquid crystal display television (LCD TV) is proposed. The proposed converter exhibits both forward and flyback operational characteristics. All semiconductors are activated and deactivated under the soft switching conditions during the switching transition without additional active devices. The switching frequency varies less than about 10 kHz for load variations, leading to minimizing the efficiency reduction under light load. Furthermore, the low di/dt and dv/dt by soft switching enhance the electromagnetic interference (EMI) performance above 1 MHz. A theoretical analysis is described in detail, and a 72-W prototype converter verifies the validity of the analysis.

This paper proposes a maximum efficiency operation strategy for three-level T-type inverter in entire operation areas. The three-level T-type inverter has higher and lower efficiency areas compared with two-level inverter. The proposed strategy aims to operate in the maximum efficiency point for the low-voltage and low-power home appliances. The three-level T-type inverter is analyzed in detail, and the two operation mode selection strategy is developed. The proposed algorithm is verified by theoretical analysis and experimental results.

This paper proposes a novel parallel control for modular ESSs through the comparative analysis of various conventional parallel control types The VSI modules for ESSs operating in parallel must satisfy the following fundamental requirements: 1) high load sharing performance, 2) tight output regulation, 3) high redundancy, 4) high applicability to both modes for ESSs However, conventional approaches failed to achieve the both goal of high redundancy and high load sharing performance at once. On the contrary, the proposed parallelism control directly controls their output current of each VSI, leading to achieving an excellent load sharing performance without knowledge of their rated-powers and how many VSIs are connected. The verification of the proposed control algorithm is verified by simulation results, 30 kW ESS prototype, and its experimental results.

In this paper, a novel modeling method of battery pack for an optimal design and effective managements of battery is suggested. The proposed modeling method using single cell information makes an optimal design of battery pack possible by expecting the characteristics of the battery pack before the battery pack is manufactured. Also, the proposed battery pack model can be highly utilized in the battery management system because the proposed model is appropriate for the system model of existing state estimation algorithms for batteries by the benefit of its simple model structure. Furthermore, cell-to-cell variation and packaging elements are taken into consideration in the process of battery pack modeling for the model accuracy. The proposed modeling method of battery pack is verified with the help of simulation and experimental results based on Li-ion battery along with battery charger and discharger. The mean absolute percentage error and root mean square error of the proposed battery pack model in dynamic test are 0.407% and 0.065, respectively.

This paper proposes an advanced state of function (SOF) estimation algorithm to determine the cranking capability of starting lighting ignition (SLI) battery. This algorithm defines the cranking resistance describing the voltage drop right after the time of cranking. And in order to increase the estimation accuracy against the effect of unpredictable battery parameter changes, a process of online update for cranking resistance is newly proposed by utilizing the specific frequency related to the cranking resistance. The validity of the proposed SOF estimation algorithm along with the online cranking resistance update process is verified by experimental results with LiFePO4 (LFP) battery.

In this paper, for the development of a safe and reliable DC home appliance suitable for DC home power supply system, we classified a number of inherent problems with help of the comparative analysis of existing AC and new DC home appliance. Several new technical problems of DC home appliances are mainly linked to the DC transient state. Among them, this paper concentrates on start-up inrush current problem, uni-polarity problem, and heavy DC load control problem. And to address these problems, we herein present an implementation of robust safety circuits for DC home appliances. Specifically, we investigate several multi-circuit countermeasures and select the best among them through comparative evaluation, based on theoretical, simulational, and experimental results.

This paper carries out a series of analysis of power system using Gallium Nitride (GaN) FET which has wide band gap (WBG) characteristics comparing to conventional Si MOSFET-used power system. At first, for comparison of each semiconductor device, the switching-transient parameter is quantitatively extracted from released information of GaN FET. And GaN FET model which reflect this dynamic property is configured. By using this model, the performance of GaN FET is analyzed comparing to Si MOSFET. Also, in order to enable a representative assessment on the power system level, Si MOSFET and GaN FET are applied to the most common structure of power system, full-bridge, and each power systems are compared based on various criteria, such as performance, efficiency and power density. The entire process is verified with the aid of mathematical analysis and simulation.

Pseudomonas fluorescens , a widespread Gram-negative bacterium, is an ideal protein manufacturing factory (PMF) because of its safety, robust growth, and high protein production. P. fluorescens possesses a type I secretion system (T1SS), which mediates secretion of a thermostable lipase (TliA) and a protease (PrtA) through its ATP-binding cassette (ABC) transporter. Recombinant proteins in P. fluorescens are attached to the C-terminal signal region of TliA for transport as fusion proteins to the extracellular medium. However, intrinsic TliA from the P. fluorescens genome interferes with detection of the recombinant protein and the secreted recombinant protein is hydrolyzed, due to intrinsic PrtA, resulting in decreased efficiency of the PMF. In this research, the lipase and protease genes of P. fluorescens SIK W1 were deleted using the targeted gene knockout method. Deletion mutant P. fluorescens Δ tliA Δ prtA secreted fusion proteins without TliA or protein degradation. Using wild-type P. fluorescens as an expression host, degradation of the recombinant protein varied depending on the type of culture media and aeration; however, degradation did not occur with the P. fluorescens Δ tliA Δ prtA double mutant irrespective of growth conditions. By homologous expression of tliA and the ABC transporter in a plasmid, TliA secreted from P. fluorescens Δ prtA and P. fluorescens Δ tliA Δ prtA cells was found to be intact, whereas that secreted from the wild-type P. fluorescens and P. fluorescens Δ tliA cells was found to be hydrolyzed. Our results demonstrate that the P. fluorescens Δ tliA Δ prtA deletion mutant is a promising T1SS-mediated PMF that enhances production and detection of recombinant proteins in extracellular media.

This paper presents a charging strategy to minimize losses in a lithium-ion polymer battery for an electric vehicle. The proposed charging method which considers the variation of battery internal impedance according to state of charge and C-rate significantly reduces charging losses. Experiment results for a cell prove that the proposed charging method reduces loss by 41.9 % compared to a conventional constant-current charging. Moreover, a 3.3 kW prototype on-board charger is built to investigate the entire reduction of losses in an electric vehicle charging system which includes a 12 kWh battery pack considering capacity deviation. Additionally, the feasibility of the proposed charging strategy is examined according to the charger capacity, and it is shown that the effect is enhanced with increasing charger capacity. It is also revealed that the loss reduction due to the proposed strategy is equivalent to an improved efficiency of 3.35% on a 52.8 kW charger with an average efficiency of 94.49%.

This paper describes a theoretical and experimental study on a seamless transfer control strategy for the parallel operation of three-phase voltage source inverters (VSIs) for energy storage systems (ESSs). Moreover, phase-locked loop, seamless transfer control, and parallel control algorithm are optimized for simplicity in order to implement in a unified-controller. Finally, the proposed algorithm is validated through informative simulation waveforms and experimental results

In this paper, an enhanced modeling method for accurate equivalent circuit model (ECM) of Li-ion battery is proposed. Modeling with curve fitting is analyzed and consequently, adaptive experimental conditions and appropriate fitting methods are proposed. An inaccurate phenomenon of the existing modeling method caused by inner capacitive impedance is analyzed. For matching model output and battery cell data during charge or discharge, model parameters are corrected recursively. Informative experimental single cell tests are carried out to verify improved accuracy of the proposed battery modeling.

The gastrointestinal mucosa has a remarkable ability to repair damage with the support of epidermal growth factor (EGF), which stimulates epithelial migration and proliferative reepithelialization. For the treatment of mucosal injuries, it is important to develop efficient methods for the localized delivery of mucoactive biotherapeutics. The basic idea in the present study came from the assumption that an intestinal probiotic vehicle can carry and deliver key recombinant medicinal proteins to the injured epithelial target in patients with intestinal ulcerative diseases, including inflammatory bowel disease. The study was focused on the use of the safe probiotic E. coli Nissle 1917, which was constructed to secrete human EGF in conjunction with the lipase ABC transporter recognition domain (LARD). Using the in vitro physically wounded monolayer model, ABC transporter-mediated EGF secretion by probiotic E. coli Nissle 1917 was demonstrated to enhance the wound-healing migration of human enterocytes. Moreover, the epithelial wound closure was dependent on EGF receptor-linked activation, which exclusively involved the subsequent signaling pathway of the mitogen-activated protein kinase kinase (MEK) extracellular-related kinases 1 and 2 (ERK1/2). In particular, the migrating frontier of the wounded edge displayed the strongest EGF receptor-linked signaling activation in the presence of the recombinant probiotic. The present study provides a basis for the clinical application of human recombinant biotherapeutics via an efficient, safe probiotic vehicle.

This paper provides a safety guideline for DC supplied home appliances through the comparative analysis of existing safety guideline for AC supplied home appliances. For this purpose, a predictive DC home appliance model is suggested and in special international safety standards of AC appliances are also analyzed. Moreover, a DC distribution system is built to verify the validity of the proposed safety guideline. The detailed analyzing process is explained with help of informative experimental results.

Znic sulfide (ZnS) thin films were deposited on glass substrates by radio frequency magnetron sputtering. The substrate temperature varied from room temperature (RT) to . The structural and optical properties of ZnS films were studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive analysis of X-ray (EDAX) and UV-visible transmission spectra. The XRD analyses reveal that ZnS films have cubic structures with (111) preferential orientation, whereas the diffraction patterns sharpen with the increase in substrate temperatures. The FESEM images indicate that ZnS films deposited at have nano-sized grains with a grain size of ~ 67 nm. Then films exhibit relatively high transmittance of 80% in the visible region, with an energy band gap of 3.71 eV. One obvious result is that the energy band gap of the film increases with increasing the substrate temperatures.

Glucose and xylose are the most abundant materials in nature which can be used to produce ethanol by yeast fermentation. Three combinations of cultivation with glucose and xylose were carried out; separated, co-culture, and sequential fermentation with Saccharomyces cerevisiaeand Pichia stipitis. In the separated fermentation, S. cerevisiae fermented glucose to produce 14.5 g/l ethanol from 29.4 g/l glucose but hardly used xylose. However, P. stipitisutilized not only glucose but also xylose to produce ethanol 11.9 g/l and 11.6 g/l from 29.4 g/l glucose and 29.0 g/l xylose, respectively. In the mixture of glucose and xylose, P. stipitisfermented both sugars, producing 21.1 g/l ethanol while S. cerevisiaefermented only glucose, producing 13.4 g/l ethanol. In the co-culture and sequential fermentation, the co-culture showed more efficient ethanol productivity with 18.6 g/l ethanol than the sequential fermentation with 12.4 g/l ethanol. To investigate the effect of nutrients in the growth of microorganisms and ethanol production, yeast nitrogen base (YNB) was used in the sequential fermentation with S. cerevisiaeand P. stipitis. YNB supplemented some nutrients which S. cerevisiaeused up in the broth and the culture showed increased growth rate, increased consumption of xylose, and increased ethanol productivity producing 22.5 g/l ethanol from 54.6 g/l sugar with a yield of 0.41 g/g.

Mucosal epithelia sense external stress signals and transmit them to the intracellular cascade responses. Ribotoxic stress-producing chemicals such as deoxynivalenol (DON) or other trichothecene mycotoxins have been linked with gastrointestinal inflammatory diseases by Fusarium-contamination. The purpose of this study was to test the hypothesis that DON evokes the epithelial sentinel signals of RNA-dependent protein kinase (PKR) and early growth response gene 1 (EGR-1), which together contribute to the pro-inflammatory cytokine interleukin 8 (IL-8) in human intestinal epithelial cells. PKR suppression by the dominant negative PKR expression attenuated DON-stimulated interleukin-8 production. Moreover, 1L-8 transcriptional activation by DON was also reduced by PKR inhibition in the human intestinal epithelial cells. Treatment with the PKR inhibitor also suppressed EGR-1 promoter activity, mRNA and protein induction, although mitogen-activated protein (MAP) kinases such as extracellular signal-regulated protein kinases (ERK) 1/2, p38, c-Jun N-terminal Kinase (INK) were little affected or even enhanced in presence of a PKR inhibitor. These patterns were also compared in the EGR-1-suppressed cells, which showed much more suppressed production of 1L-8. All things taken into consideration, DON-activated sentinel signals of EGR-1 via PKR mediated interleukin-8 production in human intestinal epithelial cells, which provide insight into the possible general mechanism associated with mucosal inflammation as an intestinal toxic insult by ribotoxic trichothecene mycotoxins.

PLZT ferroelectric thin films were deposited on Pt/Ti//Si substrate with buffer layer in between by rf magnetron sputtering method. In order to investigate the effect of Ar/ partial pressure ratio on the ferroelectric properties of PLZT thin films, PLZT thin films were deposited at various Ar/ partial pressure ratio ; 27/1.5 seem, 23/5.5 seem, 21/7.5 seem and 19/9.5 seem. The crystallinities of PLZT thin films were analyzed by XRD. The surface morphology was observed using FE-SEM. The P-E hysteresis loops, the remanent polarization characteristics and the leakage current characteristics were obtained using a Precision LC. The crystallinity and elaborateness of PLZT thin films were decreased as increasing the oxygen partial pressure ratio. And preferred orientation of PLZT thin films changed from (110) plane to (111) plane. The oxygen partial pressure ratio affects the thin film surface morphology and the ferroelectric properties.

Human mesenchymal stromal cells (MSCs) offer great hope for the treatment of tissue degenerative and immune diseases, but their phenotypic similarity to dermal fibroblasts may hinder robust cell identification and isolation from diverse tissue harvests. To identify genetic elements that can reliably discriminate MSCs from fibroblasts, we performed comparative gene and microRNA expression profiling analyses with genome-wide oligonucleotide microarrays. When taken globally, both gene and microRNA expression profiles of MSCs were highly similar to those of fibroblasts, accounting well for their extensive phenotypic and functional overlaps. Scattered expression differences were pooled to yield an MSC-specific molecular signature, consisting of 64 genes and 21 microRNAs whose expressions were at least 10-fold and two-fold higher, respectively, in MSCs compared with fibroblasts. Genes either encoding transmembrane proteins or associated with tumors were relatively abundant in this signature. These data should provide the molecular basis not only for the discovery of novel diagnostic markers discriminating MSCs from fibroblasts, but also for further studies on MSC-specific signaling mechanisms.

This paper describes a forensic science simulation programme applicable for use in colleges. Students were asked to find a putative suspect by DNA fingerprinting using a simple protocol developed in this study. DNA samples were obtained from a hair root and a drop of blood, common sources of DNA in forensic science. The DNA fingerprinting protocol uses PCR to amplify Variable Number Tandem Repeat (VNTR) sequences with five set of primers. Although there was some variation in the quality of DNA fingerprinting results among students, the students generally carried out the program successfully by correctly identifying the suspect. The inquiry-based problem solving approach of this programme facilitates an understanding of the basic concepts of biotechnology and its application.

To investigate the molecular mechanism of the airway inflammation by Pseudomonas fluorescens, effects on the inflammatory mediators such as interleukin-8 (IL-8), cyclooxygenase-2 (COX-2), macophage inhibitory cytokine 1 (MIC-1) were assessed in the human alveolar epithelial cells. Exposure to P. fluorescens and its recombinant bacteria suppressed cellular viability in the A549 epithelial cells and pro-inflammatory cytokine interleukin-8 production. However, pro-inflammatory prostaglandin-producing COX-2 protein was not altered by P. fluorescens though its mRNA was slightly elevated. As the inhibitory cytokine for the pro-inflammatory mediators, MIC-1 expression was monitored in A549 cells. MIC-1 gene induction was not significantly enhanced but the protein processing was changed by exposure to P. fluorescens. Pro-protein form of MIC-1 () was cleaved into active form mature MIC-1 () and propeptide () by the bacteria exposure. MIC-1 activation can contribute to the suppression of cellular viability by P. fluorescens and can retard IL-8-induced monocyte recruitment. However, sustained activation of MIC-1 can mediate the tissue injury by P. fluorescens exposure.

The purpose of this study was to investigate the effects of engaging students in Kolb's experiential learning cycle on facilitating students' simulation game performance and knowledge application skills in learning with a business simulation game. A sample was drawn from a population of business-major undergraduate students at the School of Business at Yonsei University in Seoul, Korea. A total of 57 subjects, who were enrolled in the entrepreneurship course in the fall semester of the 2006 school year, participated in the study. This study used two different types of prompt questions – the strategy question and the knowledge application questions – to engage subjects in the reflective observation step and the abstract conceptualisation step of Kolb's experiential learning cycle respectively. The results of data analysis revealed that subjects, who were engaged both in the reflective observation step and the abstract conceptualisation step of Kolb's experiential learning cycle, scored higher in the knowledge application posttest, and performed better in the business simulation game than subjects who were engaged only in the reflective observation step. Data analysis also found that subjects' knowledge application skills were positively correlated with their simulation game performance scores. The survey results indicated that subjects who were engaged both in the reflective observation step and the abstract conceptualisation step of Kolb's experiential learning cycle perceived their learning experience more positively than subjects who were engaged only in the reflective observation step did, and furthermore, subjects' positive perceptions of their learning experience were positively correlated with their simulation game performance scores.

In this paper, a novel power factor correction (PFC)-inverter topology with enhanced performance is proposed for applying to electric vehicles (EVs) and energy storage system (ESS). The proposed topology can be operated as the several modes which include one inverter mode and four types of PFC mode. And operation method is analyzed in detail according to each mode. The feasibility of the proposed topology is experimentally verified with the help of an actual prototype.

The analysis and design process of the LCL filter with passive damping circuits for threephase grid-connected inverter are presented based on the generalized model of LCL filter. Several types of the passive damping circuits in previous studies could be compared and analyzed by using the generalized model considering various design criteria of passive damping circuits. According to the analysis in this paper, a reasonable configuration of passive damping circuits for three-phase gridconnected inverters is proposed. The validity of the proposed design process is verified by informative simulation and experimental results.

In this paper, a mixed algorithm is proposed to improve SOC estimation accuracy for large-capacity Li-ion battery by using advantages of coulomb counting method, DCIR reset method, and enhanced OCV reset method. Because each method has drawbacks of accumulated SOC error during the operation in EVs, the optimal mixed algorithm is presented. Also, the weighted current value I DC based on the mathematical analysis of the second-order RC ladder model is calculated and then it is applied to methods respectively. The proposed algorithm is verified by the experimental results based on the 27 Ah LiPB. As a result, the SOC RMSE of the proposed algorithm is decreased about 2.22% by compared with the coulomb counting method.

In this paper, the energy recycle converter (ERC) is proposed for recycling the electric power wasted in the development process of the power conversion unit. ERC has an excellent performance that almost of the conversion energy of the test-unit can be reused. For experimental evaluation, the ERC prototype was designed to be 1kW non-isolated type. And its effectiveness was verified with help of 40kW ERC-rack, which is able to operate 40-ERC-modules at the same time. The developed ERC was applied as the burning and/or the aging equipment in the development process.

Pseudomonas fluorescens is an efficient platform for recombinant protein production. P. fluorescens has an ABC transporter secreting endogenous thermostable lipase (TliA) and protease, which can be exploited to transport recombinant proteins across the cell membrane. In this study, the expression vector pDART was constructed by inserting tliDEF , genes encoding the ABC transporter, along with the construct of the lipase ABC transporter recognition domain (LARD), into pDSK519, a widely used shuttle vector. When the gene for the target protein was inserted into the vector, the C-terminally fused LARD allowed it to be secreted through the ABC transporter into the extracellular medium. After secretion of the fused target protein, the LARD containing a hydrophobic C terminus enabled its purification through hydrophobic interaction chromatography (HIC) using a methyl-Sepharose column. Alkaline phosphatase (AP) and green fluorescent protein (GFP) were used to validate the expression, export, and purification of target proteins by the pDART system. Both proteins were secreted into the extracellular medium in P. fluorescens . In particular, AP was secreted in several Pseudomonas species with its enzymatic activity in extracellular media. Furthermore, purification of the target protein using HIC yielded some degree of AP and GFP purification, where AP was purified to almost a single product. The pDART system will provide greater convenience for the secretory production and purification of recombinant proteins in Gram-negative bacteria, such as Pseudomonas species.

Recent studies on dendritic cell (DC)-associated genes have been performed using monocyte-derived DCs (MoDCs) in different maturation stages. In our approach, to uncover the novel DC-associated genes and their expression profiles among the different DC subsets, we constructed a subtracted DC-cDNA library from CD1a(+), CD14(+), and CD11c(-) DCs by subtracting the genes shared with T cells, B cells, and monocytes, and we then screened the libraries with the aid of microarray technique. The genes showing remarkable specificity to DCs in the microarray analysis were selected and confirmed by semiquantitative reverse transcriptase-polymerase chain reaction. Our investigations revealed the following: (1) Genes highly expressed in myeloid DCs are those involved in antigen uptake/processing/presentation, cell metamorphosis, or chemotaxis. (2) Most of the genes previously identified in MoDCs, such as TARC, ferritin L-chain, lysosomal acid lipase, alpha- and beta-tubulin, osteopontin (Eta-1), and others, are not markedly expressed in CD11c(-) DCs regardless of their maturation status. On the other hand, specific transcription factors and MHC class II molecules, such as interferon regulatory factor-4 (IRF4) and HLA-DR, are similarly expressed in both DC subsets. (3) CD14(+) DCs retain unique features of tissue DCs, as evidenced by the gene expression profile of "no CCR7 but more CCR1" and "no TARC but abundant MCP1 and Eta-1." (4) The genes for immunoglobulin (Ig) superfamily Z39Ig, CD20-like precursor, glycoprotein NMB (GPNMB), transforming growth factorbeta (TGF-beta)-induced protein (TGFBI), myeloid DAP12-associated lectin (MDL-1), and 6 novel genes are newly identified as being associated with the phenotypic expression of the DC subsets. These identifications provide important molecular information for further functional studies of the DC subsets.