Turbo Warrants under Hybrid Stochastic and Local Volatility

This paper considers the pricing of turbo warrants under a hybrid stochastic and local volatility model. The model consists of the constant elasticity of variance model incorporated by a fast fluctuating Ornstein-Uhlenbeck process for stochastic volatility. The sensitive structure of the turbo warrant price is revealed by asymptotic analysis and numerical computation based on the observation that the elasticity of variance controls leverage effects and plays an important role in characterizing various phases of volatile markets

Benefit From Directional Microphone Hearing Aids: Objective and Subjective Evaluations

ObjectivesThe aims of this study were to find and compare the effect of directional (DIR) processing of two different hearing aids via both subjective and objective methods, to determine the association between the results of the subjective and objective evaluations, and to find out individual predictive factors influencing the DIR benefit.MethodsTwenty-six hearing aid users fitted unilaterally with each two different experimental hearing aid performed modified Korean Hearing in Noise Test (K-HINT) in three DIR conditions; omnidirectional (OMNI) mode, OMNI plus noise reduction feature, fixed DIR mode. In order to determine benefits from DIR benefit within a hearing aid and compare performance of the DIR processing between hearing aids, a subjective questionnaire was administrated on speech quality (SQ) and discomfort in noise (DN) domain. Correlation analysis of factors influencing DIR benefit was accomplished.ResultsBenefits from switching OMNI mode to DIR mode within both hearing aids in K-HINT were about 2.8 (standard deviation, 3.5) and 2.1 dB SNR (signal to ratio; SD, 2.5), but significant difference in K-HINT results between OMNI and OMNI plus noise reduction algorithm was not shown. The subjective evaluation resulted in the better SQ and DN scores in DIR mode than those in OMNI mode. However, the difference of scores on both SQ and DN between the two hearing aids with DIR mode was not statistically significant. Any individual factors did not significantly affect subjective and objective DIR benefits.ConclusionDIR benefit was found not only in the objective measurement performed in the laboratory but also in the subjective questionnaires, but the subjective results was failed to have significant correlation with the DIR benefit obtained in the K-HINT. Factors influencing individual variation in perceptual DIR benefit were still hard to explain

The involvement of Eph–Ephrin signaling in tissue separation and convergence during Xenopus gastrulation movements

AbstractIn Xenopus gastrulation, the involuting mesodermal and non-involuting ectodermal cells remain separated from each other, undergoing convergent extension. Here, we show that Eph–ephrin signaling is crucial for the tissue separation and convergence during gastrulation. The loss of EphA4 function results in aberrant gastrulation movements, which are due to selective inhibition of tissue constriction and separation. At the cellular levels, knockdown of EphA4 impairs polarization and migratory activity of gastrulating cells but not specification of their fates. Importantly, rescue experiments demonstrate that EphA4 controls tissue separation via RhoA GTPase in parallel to Fz7 and PAPC signaling. In addition, we show that EphA4 and its putative ligand, ephrin-A1 are expressed in a complementary manner in the involuting mesodermal and non-involuting ectodermal layers of early gastrulae, respectively. Depletion of ephrin-A1 also abrogates tissue separation behaviors. Therefore, these results suggest that Eph receptor and its ephrin ligand might mediate repulsive interaction for tissue separation and convergence during early Xenopus gastrulation movements

Cell Labeling and Tracking Method without Distorted Signals by Phagocytosis of Macrophages

Cell labeling and tracking are important processes in understanding biologic mechanisms and the therapeutic effect of inoculated cells in vivo. Numerous attempts have been made to label and track inoculated cells in vivo; however, these methods have limitations as a result of their biological effects, including secondary phagocytosis of macrophages and genetic modification. Here, we investigated a new cell labeling and tracking strategy based on metabolic glycoengineering and bioorthogonal click chemistry. We first treated cells with tetra-acetylated N-azidoacetyl-D-mannosamine to generate unnatural sialic acids with azide groups on the surface of the target cells. The azide-labeled cells were then transplanted to mouse liver, and dibenzyl cyclooctyne-conjugated Cy5 (DBCO-Cy5) was intravenously injected into mice to chemically bind with the azide groups on the surface of the target cells in vivo for target cell visualization. Unnatural sialic acids with azide groups could be artificially induced on the surface of target cells by glycoengineering. We then tracked the azide groups on the surface of the cells by DBCO-Cy5 in vivo using bioorthogonal click chemistry. Importantly, labeling efficacy was enhanced and false signals by phagocytosis of macrophages were reduced. This strategy will be highly useful for cell labeling and tracking

Construction of the Nursing Diagnosis Ontology in Obstetric and Gynecologic Nursing Unit using Nursing Process and SNOMED CT

PURPOSE: This study was performed to propose an ontology methodology based on standardized nursing process as framework in obstetric and gynecologic nursing practice. METHODS: The instrument used in this study was based on the nursing diagnosis classification established by North American Nursing Diagnosis Association (NANDA) (2009-2011), fifth edition of the Nursing Interventions Classification (NIC) (2008), forth edition of the Nursing Outcomes Classification (NOC) (2008) developed by Iowa State University and systematized nomenclature of medicine clinical terms (SNOMED CT). The nursing records data were collected from electronic medical records of one hospital from August to October 2010. RESULTS: One hundred and forty-one nursing diagnosis statements used in obstetric and gynecologic nursing unit were linked standardized nursing classifications and constructed nursing diagnosis ontology including interoperability. CONCLUSION: Not only will this result be helpful to complete nurse's lack of knowledge and experience, it will also help to determine nursing diagnosis logically by using standardized nursing process. It will be utilized as the method to construct ontology including interoperability in other nursing units. It will be presented nursing interventions according to nursing diagnosis and thus will be easier to establish nursing planning. This can provide immediate feedback of the nursing process application

Polarized Raman scattering of epitaxial PbTiO3 thin films with coexisting c- and a-domains

Effects of the orientation of ferroelectric domains on the characteristics of polarized Raman spectra were studied using an epitaxially grown PbTiO3 thin film in which the c-axis oriented domains coexist with the a-axis oriented domains on MgO (001). To obtain polarized spectra for both two distinctive c and a domains, we have employed scattering configurations in which the relevant phonon wave vector, k, is perpendicular to the c axis of the tetragonal unit cell. Compared with the mode frequencies of single-crystal PbTiO3, a softening of the E(TO) phonons was evident for both c and a domains, suggesting the presence of a strong tensile film stress. In addition to this, we observed a splitting of the degenerate "silent" mode into two distinctive B-1 and E modes in an epitaxially grown film on MgO (001). (C) 2002 American Institute of Physics

A Toxicological Study of HangAmDan-B in Mice

AbstractThe aim of the study was to define the toxicity of HangAmDan-B (HAD-B) in mice over the short and long term. HAD-B was studied in 1-week single and 5-week repeated oral dose toxicity tests on male Imprinting Control Region mice. Doses used in 1 week single oral dose toxicity tests were 0, 0.2, 1, 5, and 25 g/kg/day and those of repeated toxicity test were 0, 0.04, 0.2, 1, and 2 g/kg/day. Blood and urine samples were assayed and their morphology observed. Numerical data were compared using Mann-Whitney U test and analysis of variance. Significantly decreased red blood cell levels in mice from S2-HAD-B, S3-HAD-B, S4-HAD-B, and S5-HAD-B groups were observed in single oral dose toxicity tests. Hemoglobin, hematocrit, and mean cell hemoglobin values in mice from the S4-HAD-B and S5-HAD-B groups were also significantly decreased. No mortalities or significant differences in all factors were observed during the dosing period of the repeated dose toxicity test. Administering 2 g/kg/day of HAD-B in mice over a 5-week period showed no significant hematological changes. However, risk of anemia with more than 5 g/kg/ day administration of HAD-B was found. In general, HAD-B appears to be safe and nontoxic, and a no observed adverse effect level in mice was established at 2 g/kg/ day. This data serves as satisfactory preclinical evidence for the safety of HAD-B should a future clinical trial for HAD-B be launched. Further studies are required to confirm these safety results and to carry out a safety trial in humans

Inhibition of T Cell Receptor Signal Transduction by Tyrosine Kinase–interacting Protein of Herpesvirus saimiri

T cells play a central role in orchestrating immunity against pathogens, particularly viruses. Thus, impairing T cell activation is an important strategy employed by viruses to escape host immune control. The tyrosine kinase–interacting protein (Tip) of the T lymphotropic Herpesvirus saimiri (HVS) is constitutively present in lipid rafts and interacts with cellular Lck tyrosine kinase and p80 endosomal protein. Here we demonstrate that, due to the sequestration of Lck by HVS Tip, T cell receptor (TCR) stimulation fails to activate ZAP70 tyrosine kinase and to initiate downstream signaling events. TCR ζ chains in Tip-expressing T cells were initially phosphorylated to recruit ZAP70 molecule upon TCR stimulation, but the recruited ZAP70 kinase was not subsequently phosphorylated, resulting in TCR complexes that were stably associated with inactive ZAP70 kinase. Consequently, Tip expression not only markedly inhibited TCR-mediated intracellular signal transduction but also blocked TCR engagement with major histocompatibility complexes on the antigen-presenting cells and immunological synapse formation. These results demonstrate that a lymphotropic herpesvirus has evolved a novel mechanism to deregulate T cell activation to disarm host immune surveillance. This process contributes to the establishment and maintenance of viral latency

Differential effect of NF-κB activity on β-catenin/Tcf pathway in various cancer cells

Abstractβ-Catenin/Tcf and NF-κB pathways play an important role in biological functions. We determined the underlying mechanisms of differential interaction between two pathways in various human cancer cell lines. NF-κB positively regulated β-catenin/Tcf pathways in human glioblastoma, whereas it has an opposite effect on β-catenin/Tcf pathways in colon, liver, and breast cancer cells. Expression of lucine zipper tumor suppressor 2 (lzts2) was positively regulated by NF-κB activity in colon, liver, and breast cancer cells, whereas negatively regulated in glioma cells. Downregulation of lzts2 increased the β-catenin/Tcf promoter activity and inhibited NF-κB-induced modulation of the nuclear translocation of β-catenin. These data indicate that the differential crosstalk between β-catenin/Tcf and NF-κB pathway in various cancer cells is resulted from the differences in the regulation of NF-κB-induced lzts2 expression