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Ferrite-bonded magnets have been extensively used in small brushless DC (BLDC) motors for low torque applications such as fans and pumps. In particular, some motors of them with ferrite-bonded magnets, frequently called as plastic magnets, do not have a rotor core in order to reduce manufacturing costs and inertia of the rotating part. Accordingly, the magnetization distribution of the bonded magnets has a polar anisotropic direction to secure more magnetic flux. As a result, the magnetization orientation of the magnets is highly significant to accurately predict the performances of the BLDC motors. This paper deals with the magnetization analysis of the polar anisotropic ferrite ring magnet applied to an outer rotor type BLDC motor. The motor is employed for an electric water pump, and its rotor including the impeller consists of only the ferrite-bonded magnet material and made by injection molding. Consequently, a magnetizing fixture and an impulse magnetizer are not used for the magnetization of the outer rotor type motor. Instead, samarium–cobalt (SmCo) magnets having a relatively high curie temperature are applied for generating magnetic field. Finally, this paper presents a process to determine the anisotropic orientations of a ferrite ring magnet by finite element method. In addition, the validity of the analysis method is verified by test results.

The development of ultra-high-strength automotive steel sheets for lightweight automobiles is still an effective strategy from the material point of view. In the case of cold-rolled steels for BIW(Body In White), it has been a long time since steel with 980MPa of UTS or higher were commercialized, and the use of 1.2GPa and 1.5GPa of cold-rolled steels is also increasing. However, in the case of hot-rolled steel for chassis, the increase in strength is not as fast as that of cold-rolled steel, because chassis parts are the lower structure of a vehicle and are very sensitive to durability.

The aim of this research is to analyze the characteristics of a core melt discharged from the reactor vessel and the spreading behavior the core melt in the reactor cavity of the SMART. First, a severe accident sequence under conservative conditions is simulated by the MELCOR code to obtain the conditions for an analysis of the spreading behavior and coolability of the ex-vessel melt. Second, the spreading behavior and coolability of the ex-vessel melt are analyzed by the MELTSPREAD code. The level, temperature, and pressure of the water in the cavity as well as the temperature, mass, composition, and discharge velocity of the melt were utilized to construct the ex-vessel analysis. The melt spread only to part of the cavity, and that the height of the corium in a static state was less than 25 cm. The characteristics of a small modular reactor on the spreading behavior and coolability of melt were analyzed. In the SMART, the amount of melt discharged into the cavity is relatively small and the area of the cavity is sufficiently large when compared to a high-power pressurized water reactor. It was found that the coolability of an ex-vessel core melt can be sufficiently secured.

ABSTRACTHSR bridges are exposed to repetitive dynamic loading induced by the passage of high-speed trains (HSTs). Moving loads from HSTs can amplify the dynamic responses of bridges. The dynamic amplification factor (DAF) has been measured by the ratio between maximum dynamic to static responses of bridges when train passes over it. It is difficult to measure the static response during train operation. This study proposes a new framework to assess the DAF of HSR bridges using a multi-sensor fusion technique, which separates the total bridge response into the static and dynamic responses using a single measurement. The proposed method generates time-varying dynamic magnification by calculating the ratio of extracted dynamic response to static response at each measured time step. This method was applied to an HSR bridge under resonance conditions in South Korea and provides a clear understanding of how HSR bridges in resonance.

We fabricated a privacy film that can be electrically switched between a wide viewing angle (Share) mode and a narrow viewing angle (Privacy) mode using Polymer Dispersed Liquid Crystal (PDLC) and louver. Both transmittance and privacy performance can be maximized through the optimization of the Back Light Unit (BLU) optical characteristics and the lamination of each PDLC and louver film. We named this technology as Viewing angle Control Film (VCF). Each share and privacy mode can perform its maximum feature independently through this VCF technology.

Monitoring the dendritic electrodeposition process is crucial in various fields such as energy storage devices and sensors. A variety of in situdendritic growth monitoring methods have been developed, especially for battery applications, but they require specialized cells and equipment and are often invasive, making them unsuitable for various electrochemical systems and commercial batteries. To address these challenges, a real-time impedance analysis technique was used to determine dendritic electrodeposition on microelectrodes. The “effective size” of the electrodeposit was extracted from the impedance data, and the dendritic growth was assessed in real-time by comparing “effective size” to a theoretical radius assuming hemispherical growth. The technique was validated using scanning electron microscopy imaging and finite element method simulation. Initially applied to gold electrodeposition, the method was extended to zinc electrodeposition, demonstrating potential utilization for energy storage systems.

In response to the extensive utilization of ionic circuits, including in iontronics and wearable devices, a new method for fabricating a hydrogel-based ionic circuit on a polydimethylsiloxane (PDMS) microchip is reported. Prolonged UV/ozone oxidation combined with proper surface functionalizations and a novel microchip bonding method using thiol-epoxy click reaction enable the robust attachment of the photopolymerized hydrogel to the microchannel surface for eventual operation in electrolytes as an ionic circuit. The stretchable ionic diode constructed on the PDMS microchip shows a superior rectification ratio even under tensile stress and long-term storage stability. Furthermore, the combination of the ionic circuit and unique material properties of PDMS allows us to maximize the versatility and diversify the functionalities of the iontronic device, as demonstrated in a pressure-driven ionic switch and chip-integrated ionic regulator. Its iontronic signal transmission mimicking the excitatory and inhibitory synapses also evinces the potential of the hydrogel-based iontronics on the PDMS microchip as developed toward an aqueous neuromimetic information processor while opening up new opportunities for various bioinspired applications.

As a novel approach to the in situ real-time investigation of an ITO electrode during the wet etching process, step-excitation Fourier-transform electrochemical impedance spectroscopy (FT-EIS) was implemented. The equivalent circuit parameters (e.g., Rct, Cdl) continuously obtained by the FT-EIS measurements during the entire etching process showed an electrode activation at the initial period as well as the completion of etching. The FT-EIS results were further validated by cyclic voltammograms and impedance measurements of partially etched ITO films using ferri- and ferrocyanide solution in combination with FESEM imaging, EDS, XRD analyses, and COMSOL simulation. We also demonstrated that this technique can be further utilized to obtain intact interdigitated array (IDA) electrodes in a reproducible manner, which is generally considered to be quite tricky due to delicacy of the pattern. Given that the FT-EIS allows for instantaneous snapshots of the electrode at every moment, this work may hold promise for in situ real-time examination of structural, electrokinetic, or mass transfer-related information on electrochemical systems undergoing constantly changing, transient processes including etching, which would be impossible with conventional electroanalytical techniques.

If a steam generator tube rupture (SGTR) occurs during a severe accident in a nuclear power plant, radionuclides can be released to the atmosphere as an aerosol. The release of radioactive compounds can be prevented if these compounds are deposited on the tube walls. To quantify the fraction of aerosol particles retained in the SG and to effectively trap the radioactive aerosols during a severe accident, characteristics of particle impaction on surrounding SG tube walls must be evaluated. In this study, TiO2agglomerates were used for experiments. Particle breakup and bounce behavior due to impaction were evaluated by measuring aerosol number concentration as a function of particle size and by analyzing transmission electron microscopy images before and after impaction.

AbstractA new empirical model is proposed for estimating the amount of volatile iodine in an aqueous phase. The volatile iodine concentration is estimated for highly irradiated CsI solutions in which the pH of the solution changes. The reaction of CsI solution with water radiolysis products is not balanced because radiolysis products are continuously produced under irradiation. Thus the kinetic of the chemical equation is important to determine iodine behavior in a CsI solution. An empirical model for the kinetic equation including the oxidation and reduction reaction is proposed. The proposed model was validated with a wide range of experimental data. A comparison of the experiments and predictions by the model indicated that the predicted volatile iodine from CsI solution with a concentration of 10−3to 10−4 M was in good agreement. For 10−5 M CsI solution, the predicted iodine concentration was much smaller than experimental data due to the fact that I−was rapidly converted to IO3−.

We examined the effects of tempering process and alloying elements on the microstucture, tensile properties, bendability and impact property of direct quenched (DQ), and re-austenitizing and quenched (RQ) low-carbon martensitic steels. For this purpose, four low carbon martensitic steels (Fe-0.07C-1.8Mn-Cr-Nb-Ti-B) were selected. We have investigated the effects of tempering temperature and alloying elements of chromium (Cr), titanium (Ti) and niobium (Nb) on mechanical properties and microstructures. Mechanical properties and microstructures were analyzed as well using tensile test, V-bending test, charpy V-notched impact test and electron microscopy for DQ, DQ and tempered (DQ-T), RQ and RQ and tempered (RQ-T) low-carbon martensitic steels. It has been found that the as-quenched microstructures of the DQ and RQ specimens were fully martensitic structure. Prior austenite grain size and effective grain size after quenching were larger in the case of RQ steel. In both cases, tempering made the needle-shaped carbides. It is shown that the strength decreased when the tempering temperature increased. The strengths of the DQ and DQ-T steels were 30~50MPa higher than those of the RQ and RQ-T steels. Despite the higher strength of the DQ and DQ-T states, both had similar impact properties with the RQ and RQ-T states. However, the impact properties of the Nb added RQ and RQ-T steels with fine martensite morphology exhibited higher than those of DQ and DQ-T steels.

Emulating essential synaptic working principles using a single electronic device has been an important research field in recent years. However, achieving sensitivity and energy consumption comparable to biological synapses in these electronic devices is still a difficult challenge. Here, we report the fabrication of conjugated polyelectrolyte (CPE)-based artificial synapse, which emulates important synaptic functions such as paired-pulse facilitation (PPF), spike-timing dependent plasticity (STDP) and spiking rate dependent plasticity (SRDP). The device exhibits superior sensitivity to external stimuli andlow-energy consumption. Ultrahigh sensitivity and low-energy consumption are key requirements for building up brain-inspired artificial systems and efficient electronic-biological interface. The excellent synaptic performance originated from (i) a hybrid working mechanism that ensured the realization of both short-term and long-term plasticity in the same device, and (ii) the mobile-ion rich CPE thin film that mediate migration of abundant ions analogous to a synaptic cleft. Development of this type of artificial synapse is both scientifically and technologically important for construction of ultrasensitive highly-energy efficient and soft neuromorphic electronics.

In order to develop a domestic research roadmap for severe accidents, a special committee was established by the Korean Nuclear Society. One of the subcommittees discussed the characteristics and the relevant technical issues in the stages of fission product release and physical forms of radionuclide release and transport. The group members developed a tree to identify fission product release phenomena by tracing failures of individual defense-in-depth barriers and added possible countermeasures against failure. For each elemental issue, they searched for technical problems by examining the phenomena, accident management actions, and regulatory aspects relevant to the mitigation features for containment, including mitigation strategies against containment bypass accidents. Regulatory concerns, including the source term and the acceptance criteria for radionuclide release, were also considered. They identified further research needs regarding important technical issues based on the degree of the current knowledge level in Korea and in foreign countries, looking at the significance and urgency of issues and the expected research period required to reach an advanced level of knowledge. As a result, the group identified the 12 most important and urgent issues, most of which were expected to require mid-term and long-term research periods.

The effects of two types of inert particles (binary: 180 and 500 μm or mono: 500 μm), inlet gas temperature (40–100 °C), and mass ratio of fine to inert particles (F/I) (0.05–0.2) on the batch type fluidized bed drying characteristics of fine powders were investigated in an inert media circulating fluidized bed (0.087 m-ID × 1.0 m-height). Copper dendrimer powder (X 0 = 25.0% wet basis, d p = 2.7 μm, ρ p = 5980 kg/m 3 ) and aluminum flux (Al flux) (X 0 = 30.2% wet basis, d p = 8.6 μm, ρ p = 2730 kg/m 3 ) were used as the fine humid materials, and glass beads (180 and 500 μm) were used as the inert media particles. The moisture contents of the dried powders were sufficiently low, from 0.2% to 0.7% (wet basis). The result shows that the aggregation phenomenon rarely occurs. Compared with using the mono type inert media fluidized bed dryer, the amount of dried product using an inert media circulating fluidized bed with binary inert media increased by two to three times. The maximum drying rate of the inert media circulating fluidized beds with binary inert media is higher than that of the agitated pan dryer and inert media bubbling fluidized bed dryer (mono type inert). Additionally, the optimum condition (T g = 60 °C, F/I ratio = 0.1, binary inert media) was derived from the energy efficiency. [ABSTRACT FROM AUTHOR]

A steam generator tube rupture accompanying a core damage may cause the fission product to be released to environment bypassing the containment. In such an accident, the steam generator is the major path of the radioactive aerosol release.

Transforming growth factor-β (TGF-β) is a multifunctional cytokine that regulates a wide variety of cellular functions, including cell growth, cellular differentiation, apoptosis, and wound healing. TGF-β1, the prototype member of the TGF-β superfamily, is well established as a central mediator of renal fibrosis. In chronic kidney disease, dysregulation of expression and activation of TGF-β1 results in the relentless synthesis and accumulation of extracellular matrix proteins that lead to the development of glomerulosclerosis and tubulointerstitial fibrosis, and ultimately to end-stage renal disease. Therefore, specific targeting of the TGF-β signaling pathway is seemingly an attractive molecular therapeutic strategy in chronic kidney disease. Accumulating evidence demonstrates that the multifunctionality of TGF-β1 is connected with the complexity of its cell signaling networks. TGF-β1 signals through the interaction of type I and type II receptors to activate distinct intracellular pathways. Although the Smad signaling pathway is known as a canonical pathway induced by TGF-β1, and has been the focus of many previous reviews, importantly TGF-β1 also induces various Smad-independent signaling pathways. In this review, we describe evidence that supports current insights into the mechanism and function of TGF-β-activated kinase 1 (TAK1), which has emerged as a critical signaling molecule in TGF-β-induced Smad-independent signaling pathways. We also discuss the functional role of TAK1 in mediating the profibrotic effects of TGF-β1.

In progressive kidney diseases, fibrosis represents the common pathway to end-stage kidney failure. Transforming growth factor-β1 (TGF-β1) is a pleiotropic cytokine that has been established as a central mediator of kidney fibrosis. Emerging evidence shows a complex scheme of signaling networks that enable multifunctionality of TGF-β1 actions. Specific targeting of the TGF-β signaling pathway is seemingly critical and an attractive molecular therapeutic strategy. TGF-β1 signals through the interaction of type I and type II receptors to activate distinct intracellular pathways involving the Smad and the non-Smad. The Smad signaling axis is known as the canonical pathway induced by TGF-β1. Importantly, recent investigations have shown that TGF-β1 also induces various non-Smad signaling pathways. In this review, we focus on current insights into the mechanism and function of the Smad-independent signaling pathway via TGF-β–activated kinase 1 and its role in mediating the profibrotic effects of TGF-β1.

This paper examines the effect of initial microstructure after hot rolling on the final microstructure and mechanical properties for Cu bearing Extra Low Carbon(ELC) Steel Sheets. For this purpose, two ELC steels having different initial microstructures due to different onset time of cooling after pilot hot rolling (0.4 and 1.2 second) were selected. Mechanical properties and microstructures were analyzed as well using uni-axial tensile test, electron back-scattered diffraction (EBSD) technique following pilot rolling and continuous annealing. It has been found that the reduction of onset time of cooling gives rise to the grain refinement in hot rolled sheets. The average grain sizes of hot rolled sheetss at the onset time of 0.4 and 1.2 second are 16.7μm and 20.8 μm, respectively. In addition, the planar anisotropy of the Cu bearing ELC steel sheets has improved with reducing onset time of cooling after hot rolling. However, other mechanical properties such as strength and elongation of annealed steel are similar to both cooling condition.

Abstract: In this study, the temporary structural system for a trenchless method was developed. The developed structural system is a type of hybrid member consisting of mortar-filled steel tubes laterally connected by headed reinforcements. This lateral connection gives this system not only longitudinal but also lateral stiffness. Experimental studies were carried out to evaluate the flexural strength of the developed hybrid structural system. Behaviors of each component of this structural system, such as wing plate, connection plate and headed reinforcement were also studied. Experimental results showed that the developed system had superb flexural strength. The wing plate and connection plate had a positive effect on the flexural strength. Based on the experimental results, a simple design equation to evaluate the flexural strength of the developed structural system was suggested and compared with experimental results.

OBJECTIVE: To examine the effect of interleukin 17 (IL-17) on the expression of Toll-like receptor (TLR)-2, 4, and 9 in collagen-induced arthritis (CIA) in mice. METHODS: On Days 28 and 32 after induction of CIA in mice, phosphate-buffered saline (PBS group) or IL-17 (IL-17 group) was injected into both knee joints. On Day 35, mice were sacrificed. The severity of knee joint arthritis, synovial inflammation, and bone destruction was measured by a scoring system using macrography and histological analysis. Synovial expression of TLR-2, 4, 9, IL-17, IL-1ss, tumor necrosis factor-α (TNF-α), and IL-6 was determined by real-time PCR and immunohistochemistry. Synoviocytes of CIA mice were cultured with IL-17 and with neutralizing antibodies to cytokine, and the expression of TLR-2, 4, 9, IL-1ss, TNF-α, and IL-6 was determined by real-time RT-PCR. RESULTS: In CIA mice, knee arthritis scores, synovial inflammation, bone destruction scores, and expression of synovial TLR-2, 4, and 9, IL-17, IL-1ss, TNF-α and IL-6 were higher in the IL-17 and PBS groups than in normal DBA1 mice. These variables were also significantly higher in the IL-17 group than in the PBS group. In CIA synoviocytes, IL-17 increased the expression of TLR-2, 4, and 9, and this effect was significantly alleviated by neutralizing antibodies to IL-17, IL-1ss, and IL-6. CONCLUSION: IL-17 aggravates joint inflammation and destruction, and increases the synovial expression of TLR-2, 4, and 9 by increasing IL-1ss and IL-6. These results imply that the IL-17-induced increase in expression of TLR-2, 4, and 9, and IL-1ss and IL-6 production are involved in the IL-17-induced aggravation of arthritis.

We demonstrate a two-step hybrid process for fabricating movable parts inside glass substrate using the selective laser-induced etching (SLE) process that is consisted of laser-direct writing and wet chemical etching. To obtain an influence by the optical characteristics of a glass substrate when fabricating a 3D microstructure using the SLE, we analyzed the relationship of their dimensions between the designed and the fabricated devices. Two 3D microfluidic devices are designed and fabricated on glass substrates as the demonstrations of the hybrid process: a 3D microfluidic valve device with a movable plug and a 3D microfluidic mixer with a rotatable impeller and multilayer microchannels. The valving plug and the impeller of each device are successfully moved and rotated. The smallest structure is a pillar of the impeller device, and its size is 29 μm (diameter) × 277 μm (height). We expect this study to be extended to potential applications in 3D glass microfabrication and microfluidic systems.

The purpose of this study was to investigate the expression of IL-16 in the rheumatoid synovium and the role of inflammatory cytokines and Toll-like receptor (TLR) ligands in IL-16 production by fibroblastlike synoviocytes (FLS) of rheumatoid arthritis (RA) patients. Immunohistochemical staining was performed with a monoclonal antibody to IL-16 in synovial tissues from patients with RA and likewise in patients with osteoarthritis (OA). FLS were isolated from RA synovial tissues and stimulated with IL-15, IL-1ß, IFN-?, and IL-17. The IL-16 mRNA level was assessed by semiquantitative RT-PCR and real time (RT) PCR and a comparison was made between IL-16 mRNA levels produced by RA-FLS and OA-FLS. Production of IL-16 was identified by a western blot assay, and IL-16 production after stimulation by specific ligands of TLR2 and TLR4 was assessed by RT-PCR. While immunohistochemical staining demonstrated strong expression of IL-16 mRNA in synovial tissues from patients with RA, similar findings were not present in the OA group. Moreover, mRNA expression of IL-16 by RA-FLS increased after treatment with IL-17 but not with IL-15, IL-1ß, and IFN-?. Specifically, IL-17 increased IL-16 mRNA level by RA-FLS and peripheral blood mononuclear cells in a dose-dependent manner. However, IL-17 did not stimulate IL-16 production in OA-FLS. Peptidoglycan, a selective TLR2 ligand, also increased production of IL-16 by RA-FLS dosedependently, whereas LPS, a selective TLR4 ligand, had no such stimulatory effect. The results from our data demonstrate that IL-17 and TLR2 ligands stimulate the production of IL-16 by RA-FLS.

Tubulointerstitial fibrosis is a hallmark of chronic progressive kidney disease leading to end-stage renal failure. An endogenous product of heme oxygenase activity, carbon monoxide (CO), has been shown to exert cytoprotection against tissue injury. Here, we explored the effects of exogenous administration of low-dose CO in an in vivo model of renal fibrosis induced by unilateral ureteral obstruction (UUO) and examined whether CO can protect against kidney injury. UUO in mice leads to increased extracellular matrix (ECM) deposition and tubulointerstitial fibrosis within 4 to 7 days. Kidneys of mice exposed to low-dose CO, however, had markedly reduced ECM deposition after UUO. Moreover, low-dose CO treatment inhibited the induction of α-smooth muscle actin (α-SMA) and major ECM proteins, type 1 collagen and fibronectin, in kidneys after UUO. In contrast, these anti-fibrotic effects of CO treatment were abrogated in mice carrying null mutation of Mkk3, suggesting involvement of the MKK3 signaling pathway in mediating the CO effects. Additionally, in vitro CO exposure markedly inhibited TGF-β1-induced expression of α-SMA, collagen, and fibronectin in renal proximal tubular epithelial cells. Our findings suggest that low-dose CO exerts protective effects, via the MKK3 pathway, to inhibit development of renal fibrosis in obstructive nephropathy.

We have previously demonstrated that transforming growth factor-β1(TGF-β1) rapidly activates the mitogen-activated protein kinase kinase 3 (MKK3)-p38 MAPK signaling cascade, leading to the induction of type I collagen synthesis in mouse glomerular mesangial cells (Wang L, Ma R, Flavell RA, Choi ME. J Biol Chem277: 47257–47262, 2002). In the present study, we investigated the functional role of upstream TGF-β-activated kinase 1 (TAK1) and TAK1-binding protein 1 (TAB1) in the TGF-β1signaling cascade. Rapid activation of endogenous TAK1 activity by TGF-β1was observed in mouse mesangial cells. Transient overexpression of TAK1 with TAB1 enhanced the activation of MKK3 and p38 MAPK with or without TGF-β1stimulation, whereas a dominant-negative mutant of TAK1 (TAK1DN) suppressed TGF-β1-induced activation of MKK3 and p38 MAPK. Moreover, constitutive expression of TAK1DN reduced steady-state protein levels of MKK3 and p38 MAPK as well as MKK3 phosphorylation. Increased p38α MAPK activity by ectopic expression of either TAB1 or wild-type p38α MAPK resulted in enhanced TGF-β1-induced type I collagen expression. In contrast, constitutive expression of TAK1DN inhibited collagen induction. Taken together, our data indicate that TAK1 and TAB1 play a pivotal role as upstream signal transducers activating the MKK3-p38 MAPK signaling cascade that leads to the induction of type I collagen expression by TGF-β1. In addition, our findings also suggest that TAK1 has a novel function in regulation of the steady-state protein levels of MKK3 and p38 MAPK.

Abstract: In this work, LiNi1/3Mn1/3Co1/3O2 powders were synthesized from co-precipitated spherical metal hydroxide. In the voltage range of 2.8–4.2, 2.8–4.4, and 2.8–4.6 V, the discharge capacities of LiNi1/3Mn1/3Co1/3O2 electrode were 163, 177, and 193 mAh⋅g−1, respectively. A gel polymer electrolyte (GPE) was also prepared using polyoxyalkylene glycol acrylate (POAGA) as a macromonomer. LiNi1/3Mn1/3Co1/3O2/GPE/graphite cells were prepared and their electrochemical properties were evaluated at various current densities and temperatures. The ionic conductivity of the GPE was more than 6.2 10−3 S⋅cm−1 at room temperature. POAGA-based cells were showed good electrochemical performances such as rate capability, low-temperature performance, and cycleability.

The spectral behaviors of 4-n-pentyl-4′-cyanobiphenyl (5CB) have been studied by means of temperature-dependent Raman spectroscopy in the range between −70 and 70 °C. The v(C≡N) bands in the Raman spectra were found splitting below the transition temperature from the solid to the nematic liquid crystalline phase at ∼24 °C, suggesting the existence of solid crystalline polymorphism. The interfacial structures of 5CB on metal plate surfaces have been reexamined by surface-enhanced Raman scattering (SERS) at different temperatures. On Ag and Au, the asymmetric shapes of the v(C≡N) bands suggest that there should exist different binding schemes for 5CB on metal surfaces. These asymmetric bands in the v(C≡N) stretching region were found to vary in changing temperature.

Abstract Individual neurons in the suprachiasmatic nucleus (SCN), the master biological clock in mammals, autonomously produce highly complex patterns of spikes. We have shown that most (~90%) SCN neurons exhibit truly stochastic interspike interval (ISI) patterns. The aim of this study was to understand the stochastic nature of the firing patterns in SCN neurons by analyzing the ISI sequences of 150 SCN neurons in hypothalamic slices. Fractal analysis, using the periodogram, Fano factor, and Allan factor, revealed the presence of a 1/f-type power-law (fractal) behavior in the ISI sequences. This fractal nature was persistent after the application of the GABAA receptor antagonist bicuculline, suggesting that the fractal stochastic activity is an intrinsic property of individual SCN neurons. Based on these physiological findings, we developed a computational model for the stochastic SCN neurons to find that their stochastic spiking activity was best described by a gamma point process whose mean firing rate was modulated by a fractal binomial noise. Taken together, we suggest that SCN neurons generate temporal spiking patterns using the fractal stochastic point process.

♦ Objective Increased peritoneal vasculature has been reported in long-term peritoneal dialysis (PD), and vascular endothelial growth factors (VEGFs) have been found in dialysate. High concentrations of glucose or lactate, glucose degradation products (GDPs), and low pH of dialysis solutions are all possible factors in increased peritoneal VEGF synthesis. In this study, we investigated the effects of high glucose dialysis solutions on VEGF synthesis by peritoneal vascular endothelial cells (PVECs).♦ Methods The PVECs were isolated from rat omentum and were incubated for 4 hours in three different culture media [M199 media (control), conventional dialysis solutions containing 4.25% glucose diluted with an equal volume of M199 media (HGD), and M199 media containing 118 mmol/L mannitol as an osmolar control (mannitol)]. Levels of VEGF protein in the culture supernatant were measured by ELISA, and mRNA expression was determined by Northern blot analysis. Data are presented as percent of control.♦ Results After incubation for 4 hours, the number of cells did not differ between the 3 groups. Levels of VEGF in culture supernatant were significantly higher in the HGD group (124% ± 19%, p= 0.006) as compared with the control and mannitol (85% ± 10%) groups. The mRNA expression of VEGF appeared to be higher in the HGD group (128% ± 49%) than in the control and mannitol (94% ± 18%) groups.♦ Conclusion High glucose dialysis solutions increased VEGF synthesis by PVECs. The relationship between VEGF synthesis by PVECs and neovascularization of the peritoneum observed in long-term peritoneal dialysis patients has to be studied further.

Objective The effect of long-term use of high glucose dialysate on peritoneal structure and function, and its relation with accumulation of advanced glycosylation end-product (AGE) in the peritoneum was investigated in this study.Methods Dialysates with 4.25% glucose were injected into the peritoneal cavity of normal rats for 12 weeks without (PD, n= 7) and with (1 g/L, PD+AG, n= 7) aminoguanidine in their drinking water. Rats not having intraperitoneal (IP) injection served as control (n= 9). After 12 weeks of IP injection, a 2-hour peritoneal equilibration test (PET) was performed using 30 mL 4.25% glucose dialysate. Intraperitoneal volume (IPV), dialysate-to-plasma urea ratio at 2 hours (D2/P2), the ratio of dialysate glucose at 2 hours to initial dialysate glucose (D2/D0), and the peritoneal fluid absorption rate (Qa) were evaluated. After the PET, samples of the parietal peritoneum were taken for hematoxylin and eosin (H&E) staining and immunohistochemical staining for AGE.Results The IPV and D2/D0glucose were significantly lower and Qaand D2/P2urea significantly higher in the PD group than in the control group. Aminoguanidine reversed in part the changes in IPV and D2/P2urea in the PD group; it had no effect on Qaand D2/D0glucose. The H&E staining showed a linear mesothelial lining with negligible cells and capillaries in the narrow submesothelial space in the control group. Mesothelial denudation and submesothelial infiltration of monocytes and capillary formation were observed in the PD group. Mesothelial denudation was relatively intact in the PD+AG group compared with the PD group. Submesothelial monocyte infiltration and capillary formation in the PD+AG group were not as prominent as in the PD group. Positive AGE staining was found in the submesothelial space, vascular walls, and endomysium in the PD group, while it was markedly attenuated in PD+AG group and negligible in the control group.Conclusion Long-term use of high glucose solutions induced peritoneal AGE accumulation and mesothelial denudation, and increased peritoneal permeability and peritoneal fluid absorption rate. Inhibition of peritoneal AGE accumulation prevented those functional and structural damages to the peritoneum.

To determine the presence of specific immune recognition of type II collagen (CII) and its immunodominant epitope CII (255–274) in patients with rheumatoid arthritis (RA). T cell proliferative responses to bovine CII and a synthetic peptide encompassing CII (255–274) in peripheral blood mononuclear cells (PBMC) and synovial fluid mononuclear cells (SFMC) from RA patients, and in PBMC from osteoarthritis (OA) patients and healthy controls were assayed by mixed lymphocyte culture. The stimulation index (SI) and the number of positive (SI ≥2) T cell responses to CII were higher in RA patients (n = 106) than in OA patients (n = 26) and healthy controls (n = 34). T cell responses to CII (255–274) were also enhanced in RA patients and correlated well with those to CII. In SFMC, positive responses to CII or CII (255–274) were detected in 61.9% of 42 RA patients. T cell responses to CII in SFMC were stronger and more prevalent than peripheral responses. The SI and positive responses to CII were higher in early RA than in late RA. Levels of IgG antibodies to CII in synovial fluid inversely correlated with T cell responses to CII. T cell responses to CII or CII (255–274) were enhanced in RA, especially in early disease. Synthetic peptide CII (255–274), as well as native CII, could be recognized as immunogenic antigens by T cells, particularly in the synovial fluid. These observations suggest that CII-reactive T cells play an important role in the pathogenesis of RA. Peripheral tolerance induction using CII (255–274) might be useful in the treatment of RA.

Previous research investigating the encoding, encoding-plus-storage, and extermal-storage functions of note taking has failed to equate processing opportunities among the groups. The present studies did so by having the encoding group take notes on two occasions without review, the encoding-plus-storage group take notes one time and review notes the next, and the external-storage group twice review a set of borrowed notes. Three forms of note taking were used: conventional, and note taking on skeletal and matrix frameworks. In both Experiment 1, involving lecture learning, and Experiment 2, involving text learning, an advantage was found for the encoding-plus-storage function on tests involving factual-recall and recognition performance but not on tests measuring higher-order performance. With respect to note-taking forms, no advantage existed for any form when information was acquired from lecture. When text material was used there was some advantage for conventional notes and a clear advantage for not taking notes at all, but instead twice reading the material. These findings were explained relative to observed note-taking behaviors, the opportunity for review, and the processing demands proposed by the combination of reading and note taking, particularly when notes must be classified into an existing framework.

Low TNF production and its association with TNF gene restriction fragment length polymorphism (RFLP) was demonstrated in (NZW/NZB) F1mice. However, little is known about the significance of TNF production in association with TNF gene polymorphism in human SLE. This study was designed to evaluate the role of TNF production of peripheral blood mononuclear cells (PBMC) and its association with TNFB gene polymorphism in SLE, particularly lupus nephritis. TNFB gene polymorphism was defined by PCR-NcoIRFLP. TNF productions of phytohemagglutinin (PHA)- stimulated PBMC and T cells were examined by bioassay using L929 cell line and ELISA. The PBMC stimulated by PHA from patients with SLE (n= 60) tended to secrete less amounts of TNF by bioassay (1032±184pg/ml vs1524±224pg/ml, P=0.094), and TNF-β by ELISA (P= 0.0082) than that from normal controls (n= 38). The low TNF-α producer was more frequent in nephritis than non-nephritis (34.4% vs7.1% respectively, P<0.01). TNF-β also revealed similar results (53.1% vs21.4%, P<0.05). In SLE, mean production of TNF-β was decreased in TNFB*2 homozygote (n=18) than that in TNFB*1 homozygote (n= 9) (1126.3±145 pg/ml) vs 642 ± 118.4 pg/ml, respectively, P= 0.021), whereas TNF-α production showed little difference between the two groups (710.1 ± 56.4 vs542.4 ± 71.1 pg/ml, respectively, P= 0.149). Our results demonstrate that decreased TNF production of PBMC, which was significantly associated with TNFB*2 homozygosity, could be an important predisposing factor of lupus nephritis in Koreans.

ISFRA (Integrated SFR Analysis Program for PSA) computer program has been developed for simulating the response of the PGSFR pool design with metal fuel during a severe accident. This paper describes validation of the ISFRA aerosol model against the Aerosol Behavior Code Validation and Evaluation (ABCOVE) experiments undertaken in 1980s for radionuclide transport within a SFR containment. ABCOVE AB5, AB6, and AB7 tests are simulated using the ISFRA aerosol model and the results are compared against the measured data as well as with the simulation results of the MELCOR severe accident code. It is revealed that the ISFRA prediction of single-component aerosols inside a vessel (AB5) is in good agreement with the experimental data as well as with the results of the aerosol model in MELCOR. Moreover, the ISFRA aerosol model can predict the “washout” phenomenon due to the interaction between two aerosol species (AB6) and two-component aerosols without strong mutual interference (AB7). Based on the theory review of the aerosol correlation technique, it is concluded that the ISFRA aerosol model can provide fast, stable calculations with reasonable accuracy for most of the cases unless the aerosol size distribution is strongly deformed from log-normal distribution.

Plant nitrite reductase (NiR) catalyzes the reduction of nitrite to ammonium. We examined if NiR activity is regulated by sumoylation, and found NiR was not sumoylated by E3 small ubiquitin-related modifier ligase AtSIZ1. However, its transcript level decreased in the siz1-2mutant, indicating that AtSIZ1 does not directly control NiR activity.

The mole fraction solubility of 1,4-dioxan-2-one (x1) in tetrahydrofuran, acetone, methanol, ethanol, 1-propanol, 1-butanol, and 1-pentanol were measured over the temperature range from 263.05 K to 288.45 K. The solubility of 1,4-dioxan-2-one in alcohols increases with increasing polarity of the solvent. The results were fitted by the exponential equation. The result of the solubility was well-correlated by the empirical equations:  x1 = αeβ(T/Κ) where T is absolute temperature and α and β are parameters.

The article discusses the Art Train project in Seoul, South Korea that seeks to make riding the subway more interesting by allowing artists to decorate the cars. The artists have explored different are mediums including video art and performance art. It is remarked that one benefit of the project is that it moves art out of museums and galleries so that it can be experienced by a wider audience.