13,944 research outputs found
A Study of Some Methods for Measuring CKM CP Violating Phases
We study the influence of penguin (especially, electroweak penguin) effects
on some methods of measuring the angles , , and in the
CKM unitarity triangle. We use next-to-leading order effective Hamiltonian, and
present numerical estimates based on the factorization approximation. We find
that some techniques suggested in the literature, especially for
determination, are not workable in light of the electroweak penguin effects.
Nevertheless, there are methods that would work for each angle determination.
For angle we consider mode and estimate the
penguin contamination. For angle we consider a method based on SU(3)
symmetry and carefully consider SU(3) breaking effects. We point out regions in
the parameter space where this method could be used reliably.Comment: 25 pages (Latex), 5 PS figs (uuencoded, epsf.tex
A Wisdom-Based Salesforce Development Model: The Role of Wisdom in Salesforce Training and Well-Being
The prevalence of various salesforce job stressors call for an alternative to the current salesforce training and management strategy to secure the balanced proficiency development in job skills, prosocial abilities, and personal well-being. Specifically, we compare the well-being of 258 salespeople with 153 non-sales adults. We also investigate the relationship between wisdom and life satisfaction among salespeople, and moderation effect of age on the relationship. In regression analysis, wisdom scores of salespeople were positively related to life satisfaction moderated by age. The association between wisdom and life satisfaction was significantly stronger for older rather than younger salespeople. The findings suggest that a wisdom-based salesforce development model might result in a more balanced improvement in the mastery of job requirements, the interactions between seasoned and new salespeople, and personal well-being
Large Mixing of Light and Heavy Neutrinos in Seesaw Models and the LHC
In the type-I seesaw model the size of mixing between light and heavy
neutrinos, nu and N, respectively, is of order the square root of their mass
ratio, (m_nu/m_N)^(1/2), with only one generation of the neutrinos. Since the
light-neutrino mass must be less than an eV or so, the mixing would be very
small, even for a heavy-neutrino mass of order a few hundred GeV. This would
make it unlikely to test the model directly at the LHC, as the amplitude for
producing the heavy neutrino is proportional to the mixing size. However, it
has been realized for some time that, with more than one generation of light
and heavy neutrinos, the mixing can be significantly larger in certain
situations. In this paper we explore this possibility further and consider
specific examples in detail in the context of type-I seesaw. We study its
implications for the single production of the heavy neutrinos at the LHC via
the main channel q qbar' -> W^* -> l N involving an ordinary charged lepton l.
We then extend the discussion to the type-III seesaw model, which has richer
phenomenology due to presence of the charged partners of the heavy neutrinos,
and examine the implications for the single production of these heavy leptons
at the LHC. In the latter model the new kinds of solutions that we find also
make it possible to have sizable flavor-changing neutral-current effects in
processes involving ordinary charged leptons.Comment: 27 pages, 4 figures, general form of mixing matrix included, other
minor changes made, main results unchanged, to match published versio
Activation of Egr-1 expression in astrocytes by HIV-1 Tat: new insights into astrocyte-mediated Tat neurotoxicity
Human immunodeficiency virus type 1 (HIV-1) Tat plays an important role in HIV-associated neuropathogenesis; the underlying mechanisms are still evolving. We have recently shown that HIV-1 Tat induces expression of glial fibrillary acidic protein (GFAP), a characteristic of HIV-1 infection of the central nervous system (CNS). We have also shown that the Tat-induced GFAP expression in astrocytes is regulated by p300, and that deletion of the early growth response 1 (Egr-1) cis-transacting element within the p300 promoter abolishes Tat-induced GFAP expression. In this study, we further examined the relationship between Tat and Egr-1 in astrocytes. We found increased Egr-1 protein expression in Tat-expressing human astrocytoma cells and mouse primary astrocytes. Using the Egr-1 promoter-driven firefly luciferase reporter gene assay and the site-directed mutagenesis, we demonstrated that Tat increased Egr-1 expression by transactivating the Egr-1 promoter and involving specific serum response elements (SRE) within the promoter. Consistent with these data, we showed that Tat transactivation of the Egr-1 promoter was abrogated when astrocytes were cultured in serum-reduced media. Taken together, these results reveal that Tat directly transactivates Egr-1 expression and suggest that Tat interaction with Egr-1 is probably one of the very upstream molecular events that initiate Tat-induced astrocyte dysfunction and subsequent Tat neurotoxicity
Toward a conceptual framework for data sharing practices in social sciences: A profile approach. In the proceedings of the ASIS&T 2016 Annual Meeting
This paper investigates the landscape of data-sharing practices in social sciences via the data sharing profile approach. Guided by two pre-existing conceptual frameworks, Knowledge Infrastructure (KI) and the Theory of Remote Scientific Collaboration (TORSC), we design and test a profile tool that consists of four overarching dimensions for capturing social scientistsâ data practices, namely: 1) data characteristics, 2) perceived technical infrastructure, 3) perceived organizational context, and 4) individual characteristics. To ensure that the instrument can be applied in real and practical terms, we conduct a case study by collecting responses from 93 early-career social scientists at two research universities in the Pittsburgh Area, U.S. The results suggest that there is no significant difference, in general, among scholars who prefer quantitative, mixed method, or qualitative research methods in terms of research activities and data-sharing practices. We also confirm that there is a gap between participantsâ attitudes about research openness and their actual sharing behaviors, highlighting the need to study the âbarrierâ in addition to the âincentiveâ of research data sharing
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Combination immunotherapy induces distinct T-cell repertoire responses when administered to patients with different malignancies.
BackgroundCTLA-4 blockade with ipilimumab is Food and Drug Administration-approved for melanoma as a monotherapy and has been shown to modulate the circulating T-cell repertoire. We have previously reported clinical trials combining CTLA-4 blockade with granulocyte-macrophage colony-stimulating factor (GM-CSF) in metastatic melanoma patients and in metastatic castration resistant prostate cancer (mCRPC) patients. Here, we investigate the effect that cancer type has on circulating T cells in metastatic melanoma and mCRPC patients, treated with ipilimumab and GM-CSF.MethodsWe used next-generation sequencing of T-cell receptors (TCR) to compare the circulating T cells of melanoma and mCRPC patients receiving the same treatment with ipilimumab and GM-CSF by Wilcoxon rank sum test. Flow cytometry was utilized to investigate specific T-cell populations. TCR sequencing results were correlated with each T-cell subpopulation by Spearman's rank correlation coefficient. Of note, 14 metastatic melanoma patients had samples available for TCR sequencing and 21 had samples available for flow cytometry analysis; 37 mCRPC patients had samples available for sequencing of whom 22 have TCR data available at both timepoints; 20 of these patients had samples available for flow cytometry analysis and 16 had data available at both timepoints.ResultsWhile melanoma and mCRPC patients had similar pretreatment circulating T-cell counts, treatment induces greater expansion of circulating T cells in melanoma patients. Metastatic melanoma patients have a higher proportion of clones that increased more than fourfold after the treatment compared with mCRPC patients (18.9% vs 11.0%, p=0.017). Additionally, melanoma patients compared with mCRPC patients had a higher ratio of convergent frequency (1.22 vs 0.60, p=0.012). Decreases in clonality induced by treatment are associated with baseline CD8+ T-cell counts in both patient groups, but are more pronounced in the melanoma patients (r=-0.81, p<0.001âvs r=-0.59, p=0.02).Trial registration numbersNCT00064129; NCT01363206
Augmented Reality Navigation System on Android
With the advent of the Android system, smart phones are rapidly developing and through the conveniency of accessing internet on the smart phones, a userâs location information can be accessed anywhere and anytime easily. Augmented Reality Based Technology enables the provision of variety information such as pictures and location of buildings in the navigation field. Most of the augmented reality program used to Visual Trace Method (Marker method and Markerless Method). For the Visual Trace Method, the marker installation and digital information should be assigned while the Non-visual Trace Method requires the use of hardware (G.P.S, sensors etc). Most navigation systems can only show the path from a userâs current location to their destination. In this paper, the design and implementation of an augmented reality program is discussed. It will use the smart phoneâs inbuilt camera and GPS to display a userâs surround information in real time on the smart phone. The proposed system will combine the G.P.S location-based technology and virtual trace technology to provide the user with basic information about a building they are looking for or one in their immediate surrounding
D-Brane Gauge Theories from Toric Singularities and Toric Duality
Via partial resolution of Abelian orbifolds we present an algorithm for
extracting a consistent set of gauge theory data for an arbitrary toric variety
whose singularity a D-brane probes. As illustrative examples, we tabulate the
matter content and superpotential for a D-brane living on the toric del Pezzo
surfaces as well as the zeroth Hirzebruch surface. Moreover, we discuss the
non-uniqueness of the general problem and present examples of vastly different
theories whose moduli spaces are described by the same toric data. Our methods
provide new tools for calculating gauge theories which flow to the same
universality class in the IR. We shall call it ``Toric Duality.''Comment: 38 pages, 6 figures, 2 references added and 1 equation correcte
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