2,061 research outputs found
On the Point-Splitting Method of the Commutator Anomaly of the Gauss Law Operators
We analyze the generalized point-splitting method and Jo's result for the
commutator anomaly. We find that certain classes of general regularization
kernels satisfying integral conditions provide a unique result, which, however
differs from Faddeev's cohomological result.Comment: 16 pages, RevTex, 1 figure + 1 table, uses psbox.te
Different origin of the ferromagnetic order in (Ga,Mn)As and (Ga,Mn)N
The mechanism for the ferromagnetic order of (Ga,Mn)As and (Ga,Mn)N is
extensively studied over a vast range of Mn concentrations. We calculate the
electronic structures of these materials using density functional theory in
both the local spin density approximation and the LDA+U scheme, that we have
now implemented in the code SIESTA.
For (Ga,Mn)As, the LDA+U approach leads to a hole mediated picture of the
ferromagnetism, with an exchange constant =~ -2.8 eV. This is smaller
than that obtained with LSDA, which overestimates the exchange coupling between
Mn ions and the As holes.
In contrast, the ferromagnetism in wurtzite (Ga,Mn)N is caused by the
double-exchange mechanism, since a hole of strong character is found at the
Fermi level in both the LSDA and the LDA+U approaches. In this case the
coupling between the Mn ions decays rapidly with the Mn-Mn separation. This
suggests a two phases picture of the ferromagnetic order in (Ga,Mn)N, with a
robust ferromagnetic phase at large Mn concentration coexisting with a diluted
weak ferromagnetic phase.Comment: 12 pages, 11 figure
Gauge Invariant Cutoff QED
A hidden generalized gauge symmetry of a cutoff QED is used to show the
renormalizability of QED. In particular, it is shown that corresponding Ward
identities are valid all along the renormalization group flow. The exact
Renormalization Group flow equation corresponding to the effective action of a
cutoff lambda phi^4 theory is also derived. Generalization to any gauge group
is indicated.Comment: V1: 18 pages, 2 figures; V2: Discussions improved. Version accepted
for publication in Physica Script
The Analysis of Receptor-binding Cancer Antigen Expressed on SiSo Cells (RCAS1) immunoreactivity within the microenvironment of the ovarian cancer lesion relative to the applied therapeutic strategy
RCAS1 is involved in generating the suppressive profile of the tumor microenvironment that helps cancer cells evade immune surveillance. The status of the cells surrounding the cancer nest may affect both the progression of the cancer and the development of metastases. In cases of ovarian cancer, a large number of patients do not respond to the applied therapy. The patient’s response to the applied therapy is directly linked to the status of the tumor microenvironment and the intensity of its suppressive profile. We analyzed the immunoreactivity of RCAS1 on the cells present in the ovarian cancer microenvironment in patients with the disease; these cells included macrophages and carcinoma-associated fibroblasts. Later we analyzed the immunoreactivity levels within these cells, taking into consideration the clinical stage of the cancer and the therapeutic strategy applied, such as the number of chemotherapy regiments, primary cytoreductive surgery, or the presence of advanced ascites. In the patients who did not respond to the therapy we observed significantly higher immunoreactivity levels of RCAS1 within the cancer nest than in those patients who did respond; moreover, in the non-responsive patients we found RCAS1 within both macrophages and carcinoma-associated fibroblasts. RCAS1 staining may provide information about the intensity of the immuno-suppressive microenvironment profile found in cases of ovarian cancer and its intensity may directly relate to the clinical outcome of the disease
Recursive representation of the torus 1-point conformal block
The recursive relation for the 1-point conformal block on a torus is derived
and used to prove the identities between conformal blocks recently conjectured
by R. Poghossian. As an illustration of the efficiency of the recurrence method
the modular invariance of the 1-point Liouville correlation function is
numerically analyzed.Comment: 14 pages, 1 eps figure, misprints corrected and a reference adde
The Hierarchy Principle and the Large Mass Limit of the Linear Sigma Model
In perturbation theory we study the matching in four dimensions between the
linear sigma model in the large mass limit and the renormalized nonlinear sigma
model in the recently proposed flat connection formalism. We consider both the
chiral limit and the strong coupling limit of the linear sigma model. Our
formalism extends to Green functions with an arbitrary number of pion legs,at
one loop level,on the basis of the hierarchy as an efficient unifying principle
that governs both limits. While the chiral limit is straightforward, the
matching in the strong coupling limit requires careful use of the normalization
conditions of the linear theory, in order to exploit the functional equation
and the complete set of local solutions of its linearized form.Comment: Latex, 41 pages, corrected typos, final version accepted by IJT
Potential of an Asymmetrical Agitation in Industrial Mixing
Mixing is one of the most fundamental operations in chemical engineering. Stirred tanks are widely used in the manufacture of such materials as chemicals, paints, inks, electronics materials, ceramics, foods, pharmaceuticals and cosmetics. Suitable mixing is indispensable to the purpose achievement of a process. Eccentric mixing, in which an impeller installed at eccentric position in a vessel, is one of the traditional methods of promoting mixing. An asymmetrical flow which occurs in vessel is complicated, and it promotes mixing, distribution, and mass transfer. In this study, a new mixing method which eccentric mixing using a large type impeller which attracts attention in recent years is shown. The high performance of a large impeller can be combined with the advantages of an eccentric impeller by using the impeller at an eccentric position. The power consumption and mixing time for MAXBLEND, which is a type of large impeller, were investigated. The power consumption, P, and mixing time, θM, were measured under various eccentric conditions. The relation between the power number (Np) and Reynolds number (Re) and that between the dimensionless mixing time (nθM) and Re were investigated. When eccentric mixing is used industrially, we should be concerned about the horizontal load to a agitating shaft. The large oscillating horizontal load causes serious problems, such as the falling off of the impeller or the breakage of the motor, mechanical seal or gearbox. It is, therefore, important to understand the relation between these values and the impeller rotational speed when designing the mixing equipment and determining the operating conditions. In this study, the torque and horizontal load were measured in eccentric mixing under various eccentric conditions. The averages of both, the torque and the horizontal load, and their standard deviations, corresponding to the amplitude of fluctuation, were shown.Doi: 10.12777/ijse.5.2.73-80 [How to cite this article: Nishi, K., Enya, N., Sonoda, K., Misumi, R., Kaminoyama, M. (2013). Potential of an asymmetrical agitation in industrial mixing. International Journal of Science and Engineering, 5(2),73-80. Doi: 10.12777/ijse.5.2.73-80
Conformal Symmetry and the Three Point Function for the Gravitational Axial Anomaly
This work presents a first study of a radiative calculation for the
gravitational axial anomaly in the massless Abelian Higgs model. The two loop
contribution to the anomalous correlation function of one axial current and two
energy-momentum tensors, , is computed
at an order that involves only internal matter fields. Conformal properties of
massless field theories are used in order to perform the Feynman diagram
calculations in the coordinate space representation. The two loop contribution
is found not to vanish, due to the presence of two independent tensor
structures in the anomalous correlator.Comment: 34 pages, 5 figures, RevTex, Minor changes, Final version for Phys.
Rev.
Simultaneous disruption of two DNA polymerases, Polη and Polζ, in Avian DT40 cells unmasks the role of Polη in cellular response to various DNA lesions
Replicative DNA polymerases are frequently stalled by DNA lesions. The resulting replication blockage is released by homologous recombination (HR) and translesion DNA synthesis (TLS). TLS employs specialized TLS polymerases to bypass DNA lesions. We provide striking in vivo evidence of the cooperation between DNA polymerase η, which is mutated in the variant form of the cancer predisposition disorder xeroderma pigmentosum (XP-V), and DNA polymerase ζ by generating POLη−/−/POLζ−/− cells from the chicken DT40 cell line. POLζ−/− cells are hypersensitive to a very wide range of DNA damaging agents, whereas XP-V cells exhibit moderate sensitivity to ultraviolet light (UV) only in the presence of caffeine treatment and exhibit no significant sensitivity to any other damaging agents. It is therefore widely believed that Polη plays a very specific role in cellular tolerance to UV-induced DNA damage. The evidence we present challenges this assumption. The phenotypic analysis of POLη−/−/POLζ−/− cells shows that, unexpectedly, the loss of Polη significantly rescued all mutant phenotypes of POLζ−/− cells and results in the restoration of the DNA damage tolerance by a backup pathway including HR. Taken together, Polη contributes to a much wide range of TLS events than had been predicted by the phenotype of XP-V cells
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