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Gangliosides exist in glycosphingolipid-enriched domains on the cell membrane and regulate various functions such as adhesion, differentiation, and receptor signaling. Ganglioside GM3 by ST3GAL5 enzyme provides an essential function in the biosynthesis of more complex ganglio-series gangliosides. However, the role of gangliosides GM3 in porcine oocytes during in vitro maturation and early embryo development stage has not yet understood clear. Therefore, we examined ganglioside GM3 expression patterns under apoptosis stress during maturation and preimplantation development of porcine oocytes and embryos. First, porcine oocytes cultured in the NCSU-23 medium for 44 h after H2O2 treated groups (0.01, 0.1, 1 mM). After completion of meiotic maturation, the proportion MII (44 h) was significantly different among control and the H2O2 treated groups (76.8±0.3 vs 69.1±0.4; 0.01 mM, 55.7±1.0; 0.1 mM, 38.2±1.6%; 1 mM, P

Biodegradable polyfumarateurethane (PFU) for use as a bupivacaine delivery vehicle, synthesized using di-(2-hydroxypropyl fumarate) (DHPF), polyethylene glycol (PEG) and 1,6-hexamethylene diisocyanate (HMDI), was designed to be degradable through the hydrolysis and enzymatic degradation of the ester bonds in its polymer backbone. Using a water-in-oil-in-water double emulsion techniques, nanoparticles encapsulating water or fluorescein isothiocyanate (FITC) were fabricated to avoid the immune system owing to the presence of PEG on their surface. The morphologies of these nanoparticles were characterized by DLS, TEM, FE-SEM, and fluorescent microscopies. The present study explored the encapsulation, loading efficiency and in vitro drug release of bupivacaine encapsulated with biodegradable PFU nanoparticles for the treatment of local anesthesia. Various concentrations of bupivacaine were encapsulated into nanoparticles and their encapsulation efficiencies and drug loading were investigated. Encapsulation efficiency was highest when 2.5% bupivacaine was encapsulated. Drug release behavior from the bupivacaine-loaded PFU nanoparticles followed a sustained release profile.

Bisphenol A (BPA) is synthetic organic compound that exhibits estrogen-like properties and it induces mitochondrial superoxide production. Melatonin (Mela) protects against BPA-mediated cell damage and apoptosis. However, the antioxidative effects of Mela against BPA-induced superoxide production in porcine oocytes are still not known. In this study, we investigated the antioxidative effects of Mela against BPA-derived superoxide on oocyte maturation in pigs. To investigate the effects of the superoxide specific scavenger, Mito-TEMPO, on porcine oocyte maturation in response to BPA exposure apoptosis proteins, we treated the oocytes with Mito-TEMPO (0.1 &micro, M) after pre-treating them with BPA (75 &micro, M) for 22 h. As expected, the reduction in meiotic maturation and cumulus cell expansion of cumulus-oocyte-complexes (COCs) in the BPA (75 &micro, M) treated group was recovered (p &lt, 0.01) by treatment with Mito-TEMPO (0.1 &micro, M). An increase in the levels of mitochondrial apoptotic proteins (AIF, cleaved Cas 3 and cleaved Parp1) in response to BPA-induced damage was also reduced by Mito-TEMPO treatment in porcine COCs. Interestingly, we confirmed the positive effects of Mela with respect to superoxide production upon BPA exposure during oocyte maturation and also confirmed the reduction in mitochondrial apoptosis in Mela (0.1 &micro, M)-treated porcine COCs. These results provide evidence for the first time that antioxidative effects of Mela on BPA-derived superoxide improve porcine oocyte maturation.

Mitochondria are highly dynamic organelles that undergo constant fusion/fission as well as activities orchestrated by large dynamin-related GTPases. These dynamic mitochondrial processes influence mitochondrial morphology, size and function. Therefore, this study was conducted to evaluate the effects of mitochondrial fission inhibitor, mdivi-1, on developmental competence and mitochondrial function of porcine embryos and primary cells. Presumptive porcine embryos were cultured in PZM-3 medium supplemented with mdivi-1 (0, 10 and 50 μM) for 6 days. Porcine fibroblast cells were cultured in growth medium with mdivi-1 (0 and 50 μM) for 2 days. Our results showed that the rate of blastocyst production and cell growth in the mdivi-1 (50 μM) treated group was lower than that of the control group (P < 0.05). Moreover, loss of mitochondrial membrane potential in the mdivi-1 (50 μM) treated group was increased relative to the control group (P < 0.05). Subsequent evaluation revealed that the intracellular levels of reactive oxygen species (ROS) and the apoptotic index were increased by mdivi-1 (50 μM) treatment (P < 0.05). Finally, the expression of mitochondrial fission-related protein (Drp 1) was lower in the embryos and cells in the mdivi-1-treated group than the control group. Taken together, these results indicate that mdivi-1 treatment may inhibit developmental competence and mitochondrial function in porcine embryos and primary cells.

In Korea, pressurized heavy water-cooled reactors (PHWR) account for 17% of operating units and have taken an important role in providing national energy supply. The recent biggest issue in domestic PHWR community was the continued operation of the Wolsong-1 CANada Deuterium Uranium (CANDU) plant, which has recently been approved to operate for 10 more years after a 30 year design life. In relation to this issue, various actions from both post-Fukushima lessons and Wolsong-1 (WS1) stress test results are being taken. In KAERI R&D, the following topics are studied to support the basis for these actions. First, PHWR severe accident issues such as (1) primary heat transport system (PHTS) overpressure protection capability, (2) containment overpressure protection capability, and (3) bypass source term are evaluated. Second, a computer tool (called MAAP–ISAAC) has been modified and updated to support analyzing Wolsong severe accident issues. Third, a decision supporting tool, called Severe Accident Management Expert (SAMEX)–CANDU, has been developed to aid emergency response experts under severe accident conditions.

Bovine somatic cell nuclear transfer (SCNT) is an important and powerful tool for basic research and biomedical and agricultural applications, however, the efficiency of SCNT has remained extremely low. In this study, we investigated the effects of cathepsin B inhibitor (E-64) supplementation of culture medium on in vitro development of bovine SCNT embryos. We initially used three concentrations of E-64 (0.1, 0.5, 1.0 μm), among which 0.5 μm resulted in the highest rate of blastocysts production after in vitro fertilization (IVF), and was therefore used for further experiments. Blastocyst development of SCNT embryos in the E-64 treatment group also increased relative to the control. Moreover, the cryosurvival rates of IVF and SCNT blastocysts were increased in E-64 treatment groups when compared with the control. On the other hand, we found that IVF and SCNT blastocysts derived from E-64-treated groups had increased total cell numbers and decreased apoptotic nuclei. Furthermore, assessment of the expression of apoptosis-related genes (Bax and Bcl-xL) in bovine IVF and SCNT blastocysts treated with E-64 by real-time RT-PCR analysis revealed suppressed expression of the pro-apoptotic gene Bax and stimulated expression of the anti-apoptotic gene Bcl-xL. Taken together, these finding indicate that addition of E-64 to embryo culture medium may have important implications for improving developmental competence and preimplantation quality in bovine IVF and SCNT embryos.

Cathepsin B is abundantly expressed peptidase of the papain family in the lysosomes, and closely related to the cell degradation system such as apoptosis, necrosis and autophagy. Abnormal degradation of organelles often occurs due to release of cathepsin B into the cytoplasm. Many studies have been reported that relationship between cathepsin B and intracellular mechanisms in various cell types, but porcine embryos has not yet been reported. Therefore, this study evaluated the effect of cathepsin B inhibitor (E-64) on preimplantation developmental competence and quality of porcine embryos focusing on apoptosis and oxidative stress. The expression of cathepsin B mRNA in porcine em-bryos was gradually decreased in inverse proportion to E-64 concentration by using real-time RT-PCR. When putative zygotes were cultured with E-64 for 24 h, the rates of early cleavage and blastocyst development were decreased by increasing E-64 concentration. However, the rate of blastocyst development in 5 μM treated group was similar to the control. On the other hand, both the index of apoptotic and reactive oxygen species (ROS) of blastocysts were sig-nificantly decreased in the 5 μM E-64 treated group compared with control. We also examined the mRNA expression levels of apoptosis related genes in the blastocysts derived from 5 μM E-64 treated and non-treated groups. Expre-ssion of the pro-apoptotic Bax gene was shown to be decreased in the E-64 treated blastocyst group, whereas expre-ssion of the anti-apoptotic Bcl-xL gene was increased. Taken together, these results suggest that proper inhibition of cathepsin B at early development stage embryos improves the quality of blastocysts, which may be related to not only the apoptosis reduction but also the oxidative stress reduction in porcine embryos.

Containment Filtered Vent Systems (CFVSs) have been mainly equipped in nuclear power plants in Europe and Canada for the controlled depressurization of the containment atmosphere under severe accident conditions. This is to keep the containment integrity against overpressure during the course of a severe accident, in which the radioactive gas-steam mixture from the containment is discharged into a system designed to remove the radionuclides. In Korea, a CFVS was first introduced in the Wolsong unit-1 nuclear power plant as a mitigation measure to deal with the threat of over pressurization, following post-Fukushima action items. In this paper, the overall features of a CFVS installation such as risk assessments, an evaluation of the performance requirements, and a determination of the optimal operating strategies are analyzed for the Wolsong unit 1 nuclear power plant using a severe accident analysis computer code, ISAAC.

An extended loss of all electric power occurred at the Fukushima Dai-ichi nuclear power plant by a large earthquake and subsequent tsunami. This event led to a loss of reactor core cooling and containment integrity functions at several units of the site, ultimately resulting in large release of radioactive materials into the environment. In order to cope with beyond-design-basis external events (BDBEEs), this study proposes the iROCS (integrated, RObust Coping Strategies) approach. The iROCS approach is characterized by classification of various plant damage conditions (PDCs) that might be impacted by BDBEEs and corresponding integrated coping strategies for each of PDCs, aiming to maintain and restore core cooling (i.e., to prevent core damage) and to maintain the integrity of the reactor pressure vessel if it is judged that core damage may not be preventable in view of plant conditions. The plant damage conditions considered in the iROCS approach include combinations of the following conditions of the critical safety functions: (1) an extended loss of AC power, (2) an extended loss of DC power (loss of the monitoring and control function at control rooms), (3) a loss of RCS inventory, and (4) a loss of secondary heat removal. From a case study for an extreme damage condition, it is shown that candidate accident management strategies should be evaluated from the viewpoint of effectiveness and feasibility against extreme damage conditions of the site and accident scenarios of the plant.Copyright © 2016 by ASME

*This paper illustrates an application of a severe accident analysis code, MAAP, to the uncertainty analysis of fission products (FPs) behaviors in case of severe reactor accidents. The MAAP code is a system level computer code capable of performing integral analyses of potential severe accident progressions in nuclear power plants, whose main purpose is to support Level 2 probabilistic safety assessment or severe accident management strategy developments. The code employs lots of user-options for supporting sensitivity and uncertainty analysis. The present application is mainly focused on determining an estimate of the FPs in release and transport processes and relative importance of the dominant contributors to the predicted FPs. Key modeling parameters and phenomenological models employed for the present uncertainty analysis are closely related to FP release correlations, vapor-aerosol equilibrium, vapor-surface equilibrium for a re-vaporization calculation, and aerosol decontamination factors. The Korean standardized nuclear power plant, OPR-1000, has been used as a reference plant for the analysis.

As a means of effectively managing severe accidents at nuclear power plants, it is important to identify and diagnose accident initiating events within a short time interval after the accidents by observing the major measured signals. The main objective of this study was to diagnose loss of coolant accidents (LOCAs) using artificial intelligence techniques, such as SVC (support vector classification) and GMDH (group method of data handling). In this study, the methodologies of SVC and GMDH models were utilized to discover the break location and estimate the break size of the LOCA, respectively. The 300 accident simulation data (based on MAAP4) were used to develop the SVC and GMDH models, and the 33 test data sets were used to independently confirm whether or not the SVC and GMDH models work well. The measured signals from the reactor coolant system, steam generators, and containment at a nuclear power plant were used as inputs to the models, and the 60 sec time-integrated values of the input signals were used as inputs into the SVC and GMDH models. The simulation results confirmed that the proposed SVC model can identify the break location and the proposed GMDH models can estimate the break size accurately. In addition, even if the measurement errors exist and safety systems actuate, the proposed SVC and GMDH models can discover the break locations without a misclassification and accurately estimate the break size.

This paper provides an evaluation of the mitigation effects for the severe accident management strategies of the Wolsong plants which are typical CANDU-6 type reactors. The evaluation includes the effect of the following six mitigation strategies: (1) injection into the primary heat transport system (PHTS), (2) injection into the calandria vessel, (3) injection into the calandria vault, (4) reduction of the fission product release, (5) control of the reactor building condition, (6) reduction of the reactor building hydrogen. The tested scenario is a loss of coolant accident with a small out-of-core break, and the thermal hydraulic and severe accident phenomenological analyses were implemented by using the ISAAC computer program. The calculation results show that the most effective means for a primary decay heat removal is a low pressure safety injection, that for a calandria vessel integrity is an end-shield cooling injection, and that for a reactor building integrity is a pressure control via local air coolers. Besides the above, the usefulness of each safety component was evaluated in this analysis.

A steam generator tube rupture (SGTR) accident, which is a partial reactor building bypass scenario, has a low probability and high consequences. SAMG has been used to manage the progression of severe accidents and the release of fission products induced by an SGTR at the Wolsong plants. Four of the six SAGs in the SAMG are used to manage the progression of a severe accident induced by an SGTR at the Wolsong plants. The results of the ISAAC code calculation have shown that the proper use the SAMG can stop a severe accident from progressing and keep the reactor building intact during a severe accident. These results confirm that the SAMG is an effective means of managing the progression of severe accidents initiated by an SGTR at the Wolsong plants.

The fission product behaviors of a severe accident sequence were analyzed for the typical pressurized light water reactor (PLWR) and heavy water reactor (PHWR) operated in Korea. The OPR-1000 and the Wolsong-2 plant were selected as reference plants. The obtained results are for:(1) the fission product release from the core, (2) the fission product distributions in a reactor coolant system, a molten corium, a reactor vessel, or a containment building, (3) the fission product release from the containment. The thermal hydraulic, severe accident phenomenological, and radiological analyses for their evaluation have been performed by using the MAAP(Modular Accident Analysis Program) and ISAAC (Integrated Severe Accident Analysis Code for CANDU Plant) computer program. Based on the ISAAC and MAAP calculation, the results show that the accident progression, including the fission product transportation, of the CANDU-6 type reactor is much more delayed than the typical PLWR, however, the possibility of a fission p...

The time evolution of an iodine (as a key and representative volatile fission product species) transport and removal is simulated to evaluate a realistic in-containment source term instead of TID-14844 under a conservative hypothetical scenario in PHWRs. Fission products in vapor and aerosol forms can be deposited onto every heat sink in a compartment and be dissolved in a water pool by different deposition mechanisms. All these reactions governing an iodine development and evolution in a containment under severe accident conditions are simulated by using the latest ISAAC 2.x version which includes modified iodine release/transport/deposition models.

Although a Level 2 PSA has been performed for the Korean Standard Power Plants (KSNPs), and that it considered the necessary sequences for an assessment of the containment integrity and source term analysis. In terms of an accident management, however, more cases causing severe core damage need to be analyzed and arranged systematically for an easy access of the results. At present, KAERI is intensively calculating the severe accident sequences for various initiating events and generating a database for the accident progression including thermal hydraulic and source term behaviors. The developed database (DB) system includes a graphical display for a plant and equipment status, previous research results by a knowledge-based technique, and the expected plant behavior. The plant model used in this paper is oriented to the cases of LOCAs related to severe accident phenomena and thus can simulate the plant behaviors of a severe accident. Therefore, the developed system may play a central role as an information's source during the decision-making for a severe accident management, and be used as a training simulator for a severe accident management.

If the reactor building sprays or local air coolers are not available, depressurization by reactor building venting is considered as a useful mitigation strategy for a severe accident management of the Wolsong plants. As the containment filtered vent system is not established in the Wolsong Units, the reactor building isolation system can be a substitute for reactor building venting. The D 2 O vapour recovery system which has a 0.76 m (30 in.) diameter penetration is expected to meet the NRC requirements. To investigate the effectiveness of the Reactor Building Venting Strategy, three kinds of accidents are analyzed: a SBO, a Small LOCA and a Large LOCA. The reactor building pressure behavior was analyzed with the ISAAC computer code for four different cases: without venting, 379 kPa(g)/345 kPa(g) (55 psig/50 psig), 345 kPa(g)/276 kPa(g) (50 psig/40 psig) and 345 kPa(g)/207 kPa(g) (50 psig/30 psig) valve open/close pressures. When the reactor building spray or local air coolers can not be operated, a depressurization strategy by using the D 2 O Vapour Recovery System could prevent a reactor building failure and reduce the amount of CsI released to the environment. The present study shows that the operation of valves at a pressure of 379 kPa(g)/345 kPa(g) (55 psig/50 psig) is safe and effective. Based on the current study, the strategy of reactor building venting is involved in severe accident management guidance-5.

An external reactor vessel cooling as a means for an in-vessel retention has been selected as one of the tentative severe accident management strategies for the Wolsong plants, which are typical CANDU 6 reactors. The strategy takes advantage of the plant-specific features: (a) the power density is low, (b) the calandria vessel and the calandria vault have large water volumes, (c) the calandria is always submerged in the water of the calandria vault during a normal operation, (d) the stainless steel layer of the molten corium is negligible even though the unoxidized Zircaloy could form a metal layer, (e) no insulation structure is designed around the calandria vessel, (f) the bottom area of the calandria is large enough to transfer a sufficient amount of the corium decay heat into the calandria vault water, and (g) the water supply from the backup water sources into the calandria vault is available for a long-term external cooling of the calandria. The above design features cause a severe accident progression to be considerably delayed, and they minimize the in-vessel retention issues applied to a certain pressurized light water reactor. Furthermore, the thermal analysis demonstrates that the molten corium on the bottom of the calandria is externally coolable in terms of the critical heat flux, although phenomenological uncertainties still exist. This paper shows the feasibility and the evaluation results of the in-vessel retention strategy via an external vessel cooling for the CANDU 6-type plants, which have not been addressed as yet.

Hedgehog (Hh) signalling regulates hepatic fibrogenesis. MicroRNAs (miRNAs) mediate various cellular processes; however, their role in liver fibrosis is unclear. Here we investigate regulation of miRNAs in chronically damaged fibrotic liver. MiRNA profiling shows that expression of miR-378 family members (miR-378a-3p, miR-378b and miR-378d) declines in carbon tetrachloride (CCl4)-treated compared with corn-oil-treated mice. Overexpression of miR-378a-3p, directly targeting Gli3 in activated hepatic stellate cells (HSCs), reduces expression of Gli3 and profibrotic genes but induces gfap, the inactivation marker of HSCs, in CCl4-treated liver. Smo blocks transcriptional expression of miR-378a-3p by activating the p65 subunit of nuclear factor-κB (NF-κB). The hepatic level of miR-378a-3p is inversely correlated with the expression of Gli3 in tumour and non-tumour tissues in human hepatocellular carcinoma. Our results demonstrate that miR-378a-3p suppresses activation of HSCs by targeting Gli3 and its expression is regulated by Smo-dependent NF-κB signalling, suggesting miR-378a-3p has therapeutic potential for liver fibrosis., Liver fibrosis is a pathogenic driver of many liver diseases, so understanding its regulation might open the door to new therapies. Here the authors perform a screen for miRNA candidates and identify that miR-378 inhibits liver fibrosis in mice by interfering with Hedgehog signalling in hepatic stellate cells.

Encountering a patient with unanticipated laryngotracheal stenosis (LTS) during anesthetic induction is challenging for an anesthesiologist. Because routine history taking and pre-anesthetic evaluation cannot rule out the possibility of LTS, other measures should be taken. Perioperative airway maintenance is considered crucial for avoiding complications such as airway edema, bleeding, obstruction, collapse, and ultimately respiratory failure and arrest. We report an unanticipated tracheal stenosis discovered during anesthetic induction that hindered endotracheal intubation. Because airway maintenance was difficult, we postponed surgery until determining the cause of the difficult entry, considered possible therapeutic approaches (both anesthetic and surgical), and provided successful surgery with a continuous epidural block.

The development of diverse polymyxin derivatives is needed to solve the toxicity and resistance problems of polymyxins. However, no platform has generated polymyxin derivatives by genetically engineering a polymyxin synthetase, which is a nonribosomal peptide synthetase. In this study, we present a two-step approach for the construction of engineered polymyxin synthetases by substituting the adenylation (A) domains of polymyxin A synthetase, which is encoded by the pmxABCDE gene cluster of Paenibacillus polymyxa E681. First, the seventh L-threonine-specific A-domain region in pmxA was substituted with the Lleucine- specific A-domain region obtained from P. polymyxa ATCC21830 to make polymyxin E synthetase, and then the sixth D-leucine-specific A-domain region (A6-D-Leu-domain) was substituted with the D-phenylalanine-specific A-domain region (A6-D-Phe-domain) obtained from P. polymyxa F4 to make polymyxin B synthetase. This step was performed in Escherichia coli on a pmxA-containing fosmid, using the lambda Red recombination system and the sacB gene as a counter-selectable marker. Next, the modified pmxA gene was fused to pmxBCDE on the chromosome of Bacillus subtilis BSK4dA, and the resulting recombinant strains BSK4-PB and BSK4-PE were confirmed to produce polymyxins B and E, respectively. We also succeeded in constructing the B. subtilis BSK4-PP strain, which produces polymyxin P, by singly substituting the A6-D-Leu-domain with the A6-D-Phe-domain. This is the first report in which polymyxin derivatives were generated by genetically engineering polymyxin synthetases. The two recombinant B. subtilis strains will be useful for improving the commercial production of polymyxins B and E, and they will facilitate the generation of novel polymyxin derivatives.

Unlike most other systems in which the emergency core cooling (ECC) water is injected into the cold-legs, the Advanced Power Reactor (APR) 1400 employs a concept of a direct vessel injection (DVI) to reduce the bypass effects of the ECC water via a break during a design basis LOCA. For this, the DVI piping is designed so that the ECC water taken from an in-containment refueling storage tank (IRWST) directly flows into the reactor pressure vessel (RPV) down-comer. The main objective of this paper is to provide the MELCOR 1.8.4 sensitivity analysis results on the evolution of the severe accidents that can be expected during the APR 1400 LOCA and the insights gained from the analysis. For this purpose, the present sensitivity analysis mainly focuses on: (1) the impact of the foregoing engineering features (i.e., DVI and IRWST) in mitigating a severe core degradation and (2) the APR 1400-specific impacts of different break locations and sizes, and an operation of the containment spray systems on the timings of the key thermal-hydraulic responses, the severe degradation of the core, and the evolution of the core materials. No significant accident management strategy that plays a great role in mitigating a further progression of severe accidents has been taken into account in the present analysis. As a result, the present analysis results can be taken as the technical basis for assessing the effectiveness of a potential severe accident management.

Concentric annular heat pipes (CAHP) were fabricated and tested to investigate their thermal characteristics. The CAHPs were 25.4 mm in outer diameter and 200 mm in length. The inner surface of the heat pipes was covered with screen mesh wicks and they were connected by four bridge wicks to provide liquid return path. Three different heat pipes were fabricated to observe the effect of change in diameter ratios between 2.31 and 4.23 while using the same outer tube dimensions. The major concern of this study was the transient response as well as isothermal characteristics of the heat pipe outer surface, considering the application as uniform heating device. A better performance was achieved as the diameter ratio increased. For the thermal load of 180 W, the maximum temperature difference on the outer surface in the axial direction of CAHP was 2.3°C while that of the copper block of the same outer dimension was 5.9°C. The minimum thermal resistance of the CAHP was measured to be 0.04°C/W. In regard to the transient response during start-up, the heat pipe showed almost no time lag to the heat source, while the copper block of the same outer dimensions exhibited about 25 min time lag.

The isothermal characteristics of a rectangular parallelepiped sodium heat pipe were investigated for high-temperature applications. The heat pipes was made of stainless steel of which the dimension was 140 m(L) ×95m(W) ×46m(H) and the thickness of the container was 5 mm. Both inner surfaces of evaporator and condenser were covered with screen meshes to help spread the liquid state working fluid. To provide additional path for the working fluid, a lattice structure covered with screen mesh wick was inserted in the heat pipe. The bottom surface of the heat pipe was heated by an electric heater and the top surface was cooled by circulating coolant. The concern in this study was to enhance the temperature uniformity at the bottom surface of the heat pipe while an uneven heat source up to 900 W was in contact. The temperature distribution over the bottom surface was monitored at more than twenty six locations. It was found that the operating performance of the sodium heat pipe was critically affected by the inner wall temperature of the condenser region where the working fluid may be changed to a solid phase unless the temperature was higher than its melting point. The maximum temperature difference across the bottom surface was observed to be 114°C for 850 W thermal load and 100°C coolant inlet temperature. The effects of fill charge ratio, coolant inlet temperature and operating temperature on thermal performance of heat pipe were analyzed and discussed.

To enhance isothermal characteristics of glass-farming surface, a rectangular parallelepiped heat pipes was fabricated, tested, and analyzed. The working fluid was sodium and the wall material was stainless steel 304. The dimension of the heat pipe was 210 (L) 140(W) 92(H)mm. A lattice structure covered with screen mesh was inserted to promote return of working fluid. The bottom side of heat pipe was heated electrically and the top side was cooled by liquid circulation. The temperature distribution at the bottom surface was of major concern and was monitored to determine isothermal characteristics. A frozen start-up of rectangular parallelepiped liquid metal heat pipe was tested. The operating mode of the sodium heat pipe was affected by the temperature of cooling zone, input heat flux, and the operating temperature of heat pipe. The heat pipe operated in a normal fashion as long as the heat flux was over 5.78W/cm, and the inside wall temperature of condenser part was above 95 The maximum temperature difference at the bottom surface was observed to be 32 when the operating temperature of the heat pipe was operating normally around 50. The result showed that a sodium heat pipe was very effective in reducing significantly the temperature difference in the glass-forming surface.

Bisphenol A (BPA) is well known as oestrogen-like chemical and it is widely used in plastic products. Many studies have reported that BPA exposure has a well-known toxicity effect on reproduction function, such as reducing the number of ovulated oocytes, oocyte quality, and maturation rate. Recently, BPA induced mitochondrial-derived reactive oxygen species (mito-ROS) and disrupted mitochondrial homeostasis by increasing of superoxide anions production. In this study, we investigated how the regulation of mito-ROS production may play a critical role in meiotic maturation and expansion of cumulus cells during the in vitro maturation progression of porcine oocytes. Furthermore, we investigated the toxicity effect of BPA exposure on mitochondrial functions and mito-ROS production during porcine oocyte maturation in vitro. All results were analysed using a 1-way ANOVA followed by Bonferroni’s and Tukey’s Multiple Comparison Test and t-tests. First, porcine oocytes were matured in NCSU-23 medium supplemented with BPA (50, 75, and 100 µM) for 44 h. Our results indicated that the rates of matured oocytes were significantly decreased by BPA exposure in a dose-dependent manner (69.4 ± 5.1, 50.9 ± 6.3, and 29.9 ± 5.8% for BPA treatments of 50, 75, and 100 μM) compared with control group (70.2 ± 7.8%; P

Unfolding protein response (UPR) is a defence mechanism during endoplasmic reticulum (ER) stress in mammalian cells. Especially, UPR genes and regulation of reactive oxygen species is involved in ER stress response on porcine oocyte maturation in vitro. Some studies have shown that melatonin treatment results in reducing oxidative stress, a protective function of free radical damage in oocyte maturation and embryo development. Also, melatonin has an important role in reducing reactive oxygen species and ER stress. However, it is unknown how the changes of UPR genes expression levels are affected the porcine oocyte maturation. In addition, there are no reports about ER stress recovery mechanism by melatonin during porcine oocyte maturation. Here, we investigated the UPR signal genes (Bip/Grp78, Atf4, p90/p50Atf6, and Xbp1) and ER-stress mediated apoptosis factors (Chop and Cleaved caspase 3) in porcine oocyte maturation in vitro. Expression of Chop and Cleaved caspase 3 mRNA levels were significantly increased (P

High-temperature data retention is a critical hurdle for the commercialization of emerging nonvolatile memories. For Conductive-Bridge RAM (CBRAM) [1], we discuss high-temperature retention in terms of the physics of quantum point contacts, and we report on a family of CBRAM cells that achieve excellent retention at temperatures exceeding 200°C.

γ-tocotrienol (GTT), an isomer of vitamin E, has been the subject of increasing interest due to its strong anti-oxidant effects. Therefore, in this study, the effects of GTT on blastocyst development, expression levels of reactive oxygen species (ROS) and apoptotic index were investigated in preimplantation porcine embryos. After in vitro maturation and fertilisation, porcine embryos were cultured for 6 days in porcine zygote medium 3 supplemented with or without GTT (200 μM) under oxidative stress conditions (200 μM hydrogen peroxide (H2O2)). Blastocyst development was significantly improved in the GTT-treated group when compared with the H2O2-treated group (P

BACKGROUND/AIMS A combination of peginterferon and ribavirin is the standard therapy for chronic hepatitis C (CHC). However, the respective study has not been carried out in a large scale in Korea. The purpose of this study was to collect the studies that have been reported in Korea in order to analyze the therapeutic effect of combination therapy and compare to find racial difference. METHODS Twenty-eight papers related to the therapeutic effect of combination therapy in CHC patients were analyzed based on pooled analysis. RESULTS Based on the analysis for genotype 1 in Korea, early virologic response (EVR), end of treatment response (ETR), and sustained virologic response (SVR) were 79.6% (125/157), 80.1% (166/207), and 62.7% (341/543). The EVR, ETR, and SVR for genotype 2 and 3 were 89.4% (119/133), 92.2% (203/220), and 84.1% (434/516). Data from other Asians showed that EVR and SVR for genotype 1 were 88.9% (290/326) and 64.4% (491/762) respectively and 88.8% (135/152), and 79.4% (151/190) for genotype 2 and 3 respectively. In Western, EVR and SVR for genotype 1 were 51.3% (1,981/3,860) and 42.4% (1,798/4,231) respectively, and for genotype 2 and 3 were 87.7% (350/399) and 77.8% (533/685) respectively. Based on the comparative analysis, no statistical difference in SVR between Koreans and other Asians (p=0.955) was observed; However, the SVR of Koreans was higher with significance than that of Westerns (p

Mucosa-associated lymphoid tissue (MALT) lymphoma is a typical primary gastrointestinal lymphoma, particularly in the stomach. Although primary rectal lymphoma is rare, it may present as a subepithelial tumor. Several techniques have been proposed for a tissue diagnosis in subepithelial tumor, including endoscopic ultrasonography (EUS)-guided fine needle aspiration (EUS-FNA), EUS-guided trucut biopsy (EUS-TCB), and tacked biopsy. However the diagnostic efficacy of these techniques appears to be limited. The unroofing technique involves removal of the overlying mucosa, thereby exposing the subepithelial lesion. It was originally reported as a method for endoscopic treatment of colorectal lymphangioma. In this case, a subepithelial tumor of the rectum was diagnosed using the endoscopic unroofing technique. This is a useful modality for the diagnosis of subepithelial tumor, because it provides histologic results in a safe and rapid manner.

Disseminated cysticercosis is a rare form of cysticercosis in which the cysticerci spread out through the whole body. We report the first case of a 39-year-old Mongolian with disseminated cysticercosis. He visited our hospital with generalized tonic-clonic seizure. After extensive investigation from brain computed tomography (CT), spine magnetic resonance imaging (MRI), whole body MRI and pathologic biopsy, he was diagnosed as having cysticercosis involving the brain, subcutaneous tissue, and skeletal muscles through the whole body. We treated him with the albendazole in which case the followed MRI showed that numbers of cystic lesions were copiously decreased. We report an unsual case of disseminated cysticercosis treated with medical therapy.

Objective : Patients with spontaneous intracerebral hemorrhage (ICH) presenting within 24 hours of symptom onset are known to be increased risk of hematoma expansion which is closely correlated with morbidity and mortality. We investigated whether tiny enhancing foci (‘Spot sign’) on axial view of 3-dimensional computed tomography angiography (3D-CTA) source images can predict subsequent hematoma expansion in spontaneous ICH. Methods : During a 2-year period (March 2007-March 2009), we prospectively evaluated 3D-CTA of 110 patients with spontaneous ICH. Based on source images of 3D-CTA, patients were classified according to presence or absence of ‘Spot sign’; ‘Spot sign’ (+) group, ‘Spot sign’ (-) group. Radiological factors and clinical outcomes were compared between two groups. Results : Hematoma expansion occurred in 16 patients (15%). Mean Glasgow Coma Scale (GCS) score of patients with hematoma expansion was significantly different compared to score of patients without hematoma expansion (5 vs. 9, p < 0.001). Nineteen patients (16%) of 110 ICH patients demonstrated ‘spot sign’ on 3D-CTA. Among the ‘spot sign’ (+) group, 53% of patients developed hematoma expansion. Conversely 7% of patients without ‘spot sign’ demonstrated the hematoma expansion (p < 0.001). Initial volume and location of hematoma were significantly not associated with hematoma expansion except shape of hematoma. Conclusion : Our study showed that patients with hematoma expansion of spontaneous ICH had significant clinical deterioration. And the fact that ‘spot sign’ (+) group have higher risk of hematoma expansion suggests the presence of ‘spot sign’ on source images of 3D-CTA can give a clue to predict hematoma expansion in spontaneous ICH.

In this paper, we studied the multi-hop broadcast algorithms for delivery of safety message in inter vehicle communication environment. In MANET environment, there are three multi-hop broadcasting schemes such as probability based methods, area based methods and topology based methods. We simulate MANET based multi-hop broadcasting schemes and evaluate the performance of our work in order to analyze the suitable of these schemes for vehicular environment.

Hepatitis C genotypes 1 and 2 are widely distributed globally. In contrast, genotype 6 is found mainly in Southeast Asia, while genotype 6 is rare in Korea. This study aims to investigate the prevalence, risk factors and clinical characteristics of patients with genotype 6 chronic hepatitis C.We retrospectively identified 133 HCV-infected patients who underwent HCV genotype analysis between January 2012 and December 2012, and analyzed the prevalence, risk factors and clinical characteristics of patients diagnosed with genotype 6 chronic hepatitis C.Among 133 patients, 53 patients (39.8%) were infected with genotype 1, 62 patients (46.6%) with genotype 2, 2 patients (1.5%) with genotype 3, 14 patients (10.5%) with genotype 6, and 2 patients (1.5%) with mixed genotypes (genotype 1 and 6). The risk factors associated with genotype 6 were acupuncture (n=4, 28.6%), intravenous drug use (n=3, 21.4%), tattoo (n=2, 14.3%), and transfusion (n=2, 14.3%). Of the 14 patients with genotype 6, 6 patients were treated with pegylated interferon and ribavirin. Five patients had reached the end of treatment. All patients reaching end of treatment for genotype 6 showed early virological response and sustained virological response.The prevalence of genotype 6 is 10.5% and mixed infections of genotype 1 and 6 are 1.5% in patients with chronic hepatitis C. A major potential risk factor is intravenous drug use and the treatment response rate to pegylated interferon plus ribavirin is high in patients with genotype 6 chronic hepatitis C. Large scale multicenter studies are needed.

Following a core uncover, the core will heat up and the fuel pin cladding will oxidize in the presence of steam. The reaction follows a parabolic rate law, and a significant cladding oxidation does not occur until the cladding temperature reaches approximately 1800 deg. F. One of the products of the cladding oxidation reaction is hydrogen, which can accumulate in the PHTS if the PHTS is intact or in the reactor building if a pathway exists from the PHTS. If the hydrogen concentration reaches 4 to 6% in the reactor building (which is very possible following a significant core damage), the hydrogen can ignite and cause a spike in the reactor building pressure and temperature. If enough hydrogen is allowed to build up in the reactor building, the ignition of the hydrogen can lead to a pressure spike that exceeds the reactor building ultimate design pressure, thereby jeopardizing the reactor buildings integrity. Even if reactor building integrity is not jeopardized by a global hydrogen burn, the fact that a global hydrogen burn could occur will prevent the TSC from exiting the SAMG. Hydrogen generation and flammability is a concern throughout most of the guidelines in the Wolsong 2 (CANDU 6more » type reactor) SAMG. The purpose of this paper is to define whether the hydrogen in the reactor building atmosphere is flammable, and to estimate the hydrogen concentration in the reactor building atmosphere based on an estimated oxidation percentage. For the Wolsong 2 this CA, four sets of hydrogen figures were developed for the case of no venting (no core/concrete interaction), a 15% venting (no core/concrete interaction), a 30% venting (no core/concrete interaction), and no venting (core/concrete interaction for 24 hours resulting in a 114 deg. F superheat and a addition of non-condensable gases). (authors)« less

Methotrexate (MTX) has been established as a standard disease-modifying anti-rheumatic drug. If adequate disease control is achieved for a reasonable period of time, tapering the MTX dosage is recommended because the chronic use of MTX can result in opportunistic infection. We present here a case of a woman with rheumatoid arthritis taking MTX, and the woman developed actively caseating endobronchial Mycobacterium intracellulare disease with pulmonary infiltrations. After discontinuing the MTX, the patient was able to tolerate 18 months of antimycobacterial treatment without flare ups of rheumatoid arthritis, and she completely recovered from nontuberculous mycobacterial respiratory disease.

The recent successful operation of a two-stage K/sub a/-band gyro-TWT amplifier at the Naval Research Laboratory has demonstrated its viability as a source of broadband high-power millimeter waves. However, it has been observed experimentally that sharp gain reductions occur at certain frequencies. In this paper, an analytical theory is presented which describes the effect of electron beam quality on the device's instantaneous bandwidth. It is shown that these observed gain dips are due to electron phase-mixing, resulting from finite beam velocity spreads, in the frequency-dependent sever. In addition, the theory demonstrates that the velocity-spread induced dips can be shifted or reduced by adjusting the magnetic field profile, circuit length, and beam axial velocity, consistent with experimental observations.

Acute renal failure with severe loin pain and patch renal ischemia after anaerobic exercise (ALPE) is a rare cause of exercise-induced acute kidney injury. Some ALPE patients also have renal hypouricemia. Mutations in the SCL22A12 gene are among the major factors of hypouricemia. Education for the prevention of relapse and genetic counseling should be recommended to ALPE patients with renal hypouricemia. This paper reports a 25-year-old man who showed recurrent exercise-induced ARF and renal hypouricemia with R90H mutation in his SCL22A12 gene.