131 research outputs found
Classical Dimensional Transmutation and Renormalization in Massive lambda phi^4 Model
Recently, Dvali, Gomez, and Mukhanov have investigated a classical lambda
phi^4 model with external source and without mass and they have clarified that
there are underlying renormalization group structure, including the phenomenon
of the dimensional transmutation, at purely classical level. Especially when
the coupling lambda is negative, the classical beta function shows the property
of asymptotic freedom as in QCD. In this paper, we investigate the lambda phi^4
model with mass, and clarify the role of the mass. The obtained classical beta
function is identical with that of the massless lambda phi^4 model up to the
corrections of the ratio of the IR cutoff to UV cutoff, and describes the
renormalization flow same as the massless theory. We also found that the
dynamically generated scale of massive theory is larger than that of massless
theory, which could be due to the screening effect of the mass term.Comment: version corrected some typos and a missing reference and to appear in
Physics Letters B, 6 page
ANP/GC-A signaling attenuates pulmonary metastasis of B16 melanoma enhanced by lipopolysaccharide or angiotensin-II
N=2 String as a Topological Conformal Algebra
We prove that critical and subcritical N=2 string theory gives a realization
of an N=2 superfield extension of the topological conformal algebra. The
essential observation is the vanishing of the background charge.Comment: 11 page
X-Band ESR Determination of Dzyaloshinsky-Moriya Interaction in 2D SrCu(BO) System
X-band ESR measurements on a single crystal of SrCu(BO) system in
a temperature range between 10 K and 580 K are presented. The temperature and
angular dependence of unusually broad ESR spectra can be explained by the
inclusion of antisymmetric Dzyaloshinsky-Moriya (DM) interaction, which yields
by far the largest contribution to the linewidth. However, the well-accepted
picture of only out-of-plane interdimer DM vectors is not sufficient for
explanation of the observed angular dependence. In order to account for the
experimental linewidth anisotropy we had to include sizable in-plane components
of interdimer as well as intradimer DM interaction in addition to the
out-of-plane interdimer one. The nearest-neighbor DM vectors lie perpendicular
to crystal anisotropy c-axis due to crystal symmetry. We also emphasize that
above the structural phase transition occurring at 395 K dynamical mechanism
should be present allowing for instantaneous DM interactions. Moreover, the
linewidth at an arbitrary temperature can be divided into two contributions;
namely, the first part arising from spin dynamics governed by the spin
Hamiltonian of the system and the second part due to significant spin-phonon
coupling. The nature of the latter mechanism is attributed to phonon-modulation
of the antisymmetric interaction, which is responsible for the observed linear
increase of the linewidth at high temperatures.Comment: 17 pages, 4 figures, submitted to PR
Tumor immune microenvironment of cutaneous angiosarcoma with cancer testis antigens and the formation of tertiary lymphoid structures
Cutaneous angiosarcoma (CAS) is a highly malignant tumor with few effective treatments. Although the indication for immune checkpoint inhibitors such as anti-PD-1 antibodies is expected to expand, there are many unknowns regarding the tumor immune microenvironment in CAS, which is generally considered an immunologically “cold” tumor. Our previous study demonstrated that tertiary lymphoid structures (TLSs) were associated with a favorable prognosis in CAS. However, we still don’t know what the difference is between cases of TLS-rich and TLS-poor. Furthermore, the number of TLSs can vary significantly between lesions in the same case, for example, between primary and recurrence. To analyze the changes in the tumor immune microenvironment in CAS in more detail, we performed comprehensive RNA sequencing using a Next-generation sequencer (NGS). Sixty-two samples from 31 cases of CAS treated at Nagoya City University were collected. NGS and gene set enrichment analysis (GSEA) were performed on 15 samples among them. Immunohistochemistry and prognostic analysis by Kaplan-Meier method were performed on all 62 samples. NGS results showed that NY-ESO-1 (CTAG1B) was significantly upregulated in the TLS-positive cases. Immune checkpoint molecules including programmed death-1 (PD-1) and programmed death-ligand 1 (PD-L1) were upregulated in TLS-negative or TLS-low cases and seemed to associate with the suppression of TLS formation. In a comparison of primary and recurrent lesions, other cancer-testis antigens (CTAs) including XAGE-1B were significantly upregulated in recurrent lesions. The number of infiltrating CD8-positive cells and TLSs showed no significant trend between primary and recurrent lesions. However, the PD-L1 expression of tumor cells was significantly lower in recurrent than in primary lesions. Chemokines correlated with NY-ESO-1 expression were CCL21 and CXCL8, and only CCL21 correlated with the number of TLS. There was no chemokine associated with XAGE-1. NY-ESO-1 and XAGE-1 are detectable by immunohistochemistry. Although each cannot be a prognostic marker by itself, they can be a helpful marker in combination with the number of TLSs. CTAs play an essential role in forming the tumor immune microenvironment in CAS. These findings are evidence that CAS is an immunologically “hot” tumor and provides us with potential therapeutic targets and encourages the expansion of immunotherapy indications
Implications of the 750 GeV gamma-gamma Resonance as a Case Study for the International Linear Collider
If the gamma-gamma resonance at 750 GeV suggested by 2015 LHC data turns out
to be a real effect, what are the implications for the physics case and upgrade
path of the International Linear Collider? Whether or not the resonance is
confirmed, this question provides an interesting case study testing the
robustness of the ILC physics case. In this note, we address this question with
two points: (1) Almost all models proposed for the new 750 GeV particle require
additional new particles with electroweak couplings. The key elements of the
500 GeV ILC physics program---precision measurements of the Higgs boson, the
top quark, and 4-fermion interactions---will powerfully discriminate among
these models. This information will be important in conjunction with new LHC
data, or alone, if the new particles accompanying the 750 GeV resonance are
beyond the mass reach of the LHC. (2) Over a longer term, the energy upgrade of
the ILC to 1 TeV already discussed in the ILC TDR will enable experiments in
gamma-gamma and e+e- collisions to directly produce and study the 750 GeV
particle from these unique initial states.Comment: 39 pages, 5 figures, 5 tables; v2: some references adde
Notoamides A-D: prenylated indole alkaloids isolated from a marine-derived fungus, Aspergillus sp.
金沢大学大学院自然科学研究科生理活性物質科学金沢大学薬学
Field-induced bound-state condensation and spin-nematic phase in SrCu(BO) revealed by neutron scattering up to 25.9 T
Bose-Einstein condensation (BEC) underpins exotic forms of order ranging from
superconductivity to superfluid 4 He. In quantum magnetic materials, ordered
phases induced by an applied magnetic field can be described as the BEC of
magnon excitations. With sufficiently strong magnetic frustration, exemplified
by the system SrCu(BO) , no clear magnon BEC is observed and the
complex spectrum of multi-magnon bound states may allow a different type of
condensation, but the high fields required to probe this physics have remained
a barrier to detailed investigation. Here we exploit the first purpose-built
high-field neutron scattering facility to measure the spin excitations of
SrCu(BO) up to 25.9 T and use cylinder matrix-product-states (MPS)
calculations to reproduce the experimental spectra with high accuracy. Multiple
unconventional features point to a condensation of bound states into a
spin-nematic phase, including the gradients of the one-magnon branches, the
presence of many novel composite two- and three-triplon excitations and the
persistence of a one-magnon spin gap. This gap reflects a direct analogy with
superconductivity, suggesting that the spin-nematic phase in
SrCu(BO) is best understood as a condensate of bosonic Cooper
pairs. Our results underline the wealth of unconventional states yet to be
found in frustrated quantum magnetic materials under extreme conditions
Supersymmetric nonperturbative formulation of the WZ model in lower dimensions
A nonperturbative formulation of the Wess-Zumino (WZ) model in two and three
dimensions is proposed on the basis of momentum-modes truncation. The
formulation manifestly preserves full supersymmetry as well as the
translational invariance and all global symmetries, while it is shown to be
consistent with the expected locality to all orders of perturbation theory. For
the two-dimensional WZ model, a well-defined Nicolai map in the formulation
provides an interesting algorithm for Monte Carlo simulations.Comment: 17 pages, uses elsart.cls, the final version to appear in Phys. Lett.
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