2,090 research outputs found

    The anomalous U(1) global symmetry and flavors from an SU(5) x SU(5)' GUT in Z12IZ_{12-I} orbifold compactification

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    In string compactifications, frequently there appears the anomalous U(1) gauge symmetry which belonged to E8×\timesE8 of the heterotic string. This anomalous U(1) gauge boson obtains mass at the compactification scale, just below 101810^{18\,}GeV, by absorbing one pseudoscalar (corresponding to the model-independent axion) from the second rank anti-symmetric tensor field BMNB_{MN}. Below the compactification scale, there results a global symmetry U(1)anom_{\rm anom} whose charge QanomQ_{\rm anom} is the original gauge U(1) charge. This is the most natural global symmetry, realizing the "invisible" axion. This global symmetry U(1)anom_{\rm anom} is suitable for a flavor symmetry. In the simplest compactification model with the flipped SU(5) grand unification, we calculate all the low energy parameters in terms of the vacuum expectation values of the standard model singlets.Comment: 18 pages, 4 figur

    Transcriptional Regulator TonEBP Mediates Oxidative Damages in Ischemic Kidney Injury

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    TonEBP (tonicity-responsive enhancer binding protein) is a transcriptional regulator whose expression is elevated in response to various forms of stress including hyperglycemia, inflammation, and hypoxia. Here we investigated the role of TonEBP in acute kidney injury (AKI) using a line of TonEBP haplo-deficient mice subjected to bilateral renal ischemia followed by reperfusion (I/R). In the TonEBP haplo-deficient animals, induction of TonEBP, oxidative stress, inflammation, cell death, and functional injury in the kidney in response to I/R were all reduced. Analyses of renal transcriptome revealed that genes in several cellular pathways including peroxisome and mitochondrial inner membrane were suppressed in response to I/R, and the suppression was relieved in the TonEBP deficiency. Production of reactive oxygen species (ROS) and the cellular injury was reproduced in a renal epithelial cell line in response to hypoxia, ATP depletion, or hydrogen peroxide. The knockdown of TonEBP reduced ROS production and cellular injury in correlation with increased expression of the suppressed genes. The cellular injury was also blocked by inhibitors of necrosis. These results demonstrate that ischemic insult suppresses many genes involved in cellular metabolism leading to local oxidative stress by way of TonEBP induction. Thus, TonEBP is a promising target to prevent AKI

    A novel approach to fabricate carbon-sphere-intercalated holey graphene electrode for high-energy-density electrochemical capacitors

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    Desirable porous structure and huge ion-accessible surface area are crucial for rapid electronic and ionic pathway electrodes in high-performance graphene-based electrochemical capacitors. However, graphene nanosheets tend to aggregate and restack because of van der Waals interaction among graphene sheets, resulting in the loss of ion-accessible surface area and unsatisfactory electrochemical performance. To resolve this daunting challenge, a novel approach is developed for the self-assembly of holey graphene sheets intercalated with carbon spheres (H-GCS) to obtain freestanding electrodes by using a simple vacuum filtration approach and a subsequent KOH activation process. Through the introduction of carbon spheres as spacers, the restacking of reduced graphene oxide (rGO) sheets during the filtration process is mitigated efficiently. Pores on rGO sheets produced by subsequent KOH activation also provide rapid ionic diffusion kinetics and high ion-accessible electrochemical surface area, both of which favor the formation of electric double-layer capacitance. Furthermore, a higher degree of graphitization of CSs in H-GCS thin film improves the electrical conductivity of the H-GCS electrode. The H-GCS electrode exhibits 207.1 F g−1 of specific capacitance at a current density of 1 A g−1 in 6 M KOH aqueous electrolyte. Moreover, the symmetric electrochemical capacitor assembled with H-GCS electrodes and organic electrolyte is capable of delivering a maximum energy density of 29.5 Wh kg−1 and a power density of 22.6 kW kg−1

    Study on Awareness of Preconception Care and Reproductive Health Behaviors in Pre-honeymooners

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    PURPOSE: The purpose of this study was 1) to examine levels of awareness on preconception care and pregnancy, and reproductive health promoting behavior among pre-honeymooners; and 2) to explore the relationship between awareness levels of preconception care and pregnancy, and reproductive health promoting behavior. METHODS: This study was a correlation design with a total of 134 participants (67 couples of pre-honeymooners). Data were collected with questionnaire. RESULTS: Mean score of self-perception of awareness of preconception care and pregnancy was 2.82 out of 4. Content awareness level was 6.83 out of 13, and reproductive health promoting behavior score was 3.02 out of 4, indicating low to mid-level. Women reported higher scores in all variables than those in men. Self-perception awareness and content awareness of care and pregnancy had a weak positive correlation (r=.18, p=.038). Reproductive health promoting behavior was positively related to self-perception awareness of care and pregnancy (r=.33, p<.001) and content awareness of care and pregnancy (r=.23, p=.008). CONCLUSION: Based on this results, a variety of nursing intervention strategies may need to promote reproductive health behavior such as raising awareness of the preconception care and pregnancy

    Oligonol Ameliorates CCl 4

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    Oxidative stress is thought to be a key risk factor in the development of hepatic diseases. Blocking or retarding the reactions of oxidation and the inflammatory process by antioxidants could be a promising therapeutic intervention for prevention or treatment of liver injuries. Oligonol is a low molecular weight polyphenol containing catechin-type monomers and oligomers derived from lychee fruit. In this study, we investigated the anti-inflammatory effect of oligonol on carbon tetrachloride- (CCl4-) induced acute hepatic injury in rats. Oral administration of oligonol (10 or 50 mg/kg) reduced CCl4-induced abnormalities in liver histology and serum AST and serum ALT levels. Oligonol treatment attenuated the CCl4-induced production of inflammatory mediators, including TNF-α, IL-1β, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) mRNA levels. Western blot analysis showed that oligonol suppressed proinflammatory nuclear factor-kappa B (NF-κB) p65 activation, phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun NH2-terminal kinase (JNK), and p38 mitogen-activated protein kinases (MAPKs) as well as Akt. Oligonol exhibited strong antioxidative activity in vitro and in vivo, and hepatoprotective activity against t-butyl hydroperoxide-induced HepG2 cells. Taken together, oligonol showed antioxidative and anti-inflammatory effects in CCl4-intoxicated rats by inhibiting oxidative stress and NF-κB activation via blockade of the activation of upstream kinases including MAPKs and Akt

    miTarget: microRNA target gene prediction using a support vector machine

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    BACKGROUND: MicroRNAs (miRNAs) are small noncoding RNAs, which play significant roles as posttranscriptional regulators. The functions of animal miRNAs are generally based on complementarity for their 5' components. Although several computational miRNA target-gene prediction methods have been proposed, they still have limitations in revealing actual target genes. RESULTS: We implemented miTarget, a support vector machine (SVM) classifier for miRNA target gene prediction. It uses a radial basis function kernel as a similarity measure for SVM features, categorized by structural, thermodynamic, and position-based features. The latter features are introduced in this study for the first time and reflect the mechanism of miRNA binding. The SVM classifier produces high performance with a biologically relevant data set obtained from the literature, compared with previous tools. We predicted significant functions for human miR-1, miR-124a, and miR-373 using Gene Ontology (GO) analysis and revealed the importance of pairing at positions 4, 5, and 6 in the 5' region of a miRNA from a feature selection experiment. We also provide a web interface for the program. CONCLUSION: miTarget is a reliable miRNA target gene prediction tool and is a successful application of an SVM classifier. Compared with previous tools, its predictions are meaningful by GO analysis and its performance can be improved given more training examples

    The Basic Study of Underwater Robot Control for Over Actuated Systems

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    In general, only six individual thrusters are required to perform 6 DOF (Degree Of Freedom) motion. Sometimes, however, more than six thrusters are used for 6 DOF motion for a variety of purposes. The over actuated systems can transit quickly from transient state caused by disturbance to steady state through the over actuated input. So in the underwater robot, the purpose of over actuated system is mainly used to maintain stable motion and position. And that systems are performed to obtain the optimal efficiency through the thruster force distribution. In this paper, we designed and fabrication the ROV (Remotely Operated Vehicle) for the basic study of over actuated underwater robot. It has 4 horizontal thrusters and 4 vertical thrusters. Using this system, we derived the thruster force distribution matrix for thruster allocation. Also, to check the kinetic characteristics of over actuated underwater robot before applying various controller, we performed the basic motion performance test and motion control test using the PD controller in the indoor engineering water basin

    Analysis of the Correlation Between the Support Performance of Supported Business for the Regional Industry

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    Reflecting the conditions and characteristics of Korea, the region's main industry is being developed to expand new job creation in the region and enhance the competitiveness of local industries. The local main business is supported to 63 main industries selected by region. The main industries in Busan include digital contents, intelligent machine parts, super precision convergence parts, mold heat treatment, and bio-health. In this study, the main industries of Busan region in 2016 conducted an analysis on the companies that support the intelligent machine parts industry. For the analysis, we collected data on the sales of supported companies, sales after business support, and employment growth. The analysis tool utilized IBM SPSS statistics 18. As a result, we confirmed the relationship between employment and sales according to support business programs. Based on the results of this study, it will be helpful for the task performing organization to identify the direction of the support program and the needs of the enterprise
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