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Background: Somatic alteration of the von Hippel-Lindau disease tumor suppressor gene (VHL) is one of the most common genetic changes observed in the sporadic, clear-cell subtype of renal cell carcinoma (RCC). However, the prognostic utility of VHL mutations has not been examined. The purpose of this study was to explore the association between VHL mutations and the risk of death from sporadic clear-cell RCC. Methods: A total of 187 Japanese patients with clear-cell RCC who underwent nephrectomy from October 1986 through December 1995 were examined for somatic VHL gene alteration. Clinicopathologic and survival data were also collected. Kaplan-Meier analyses and Cox proportional hazards models were used to explore associations. All statistical tests were two-sided. Results: A VHL alteration (mutation or hypermethylation) was detected in 108 RCC tumor samples: intragenic mutations in 98 (52%) and hypermethylation in 10 (5.3%). VHL alterations were strongly associated with better cancer-free survival and cancer-specific survival for the 134 patients with stage I-III clearcell RCC treated by radical nephrectomy (log-rank P = .024 and .023, respectively). These associations were more statistically significant among patients with relatively advanced disease (stage III [P = .014 and .010, respectively] or stage II + III [P = .002 and .009]) or higher grade tumors (G3 or higher [P = .013 and .032] or G2 or higher [P = .013 and .018]) and among patients who presented with symptoms (P = .005 and .012). VHL alterations remained an independent prognostic factor for patients with stage I-III tumors after adjustment for sex, age, stage, grading, and symptomatic presentation. VHL alterations were not associated with cancer-specific survival for the 53 patients with stage IV tumors treated with palliative or adjunctive nephrectomy (log-rank P = .760). Conclusion: The VHL alteration status may provide useful prognostic information, as a biomolecular marker, for patients with stage I-III clear-cell RCC who have undergone nephrectomy.

In this work, by casting water-soluble ammonium anthracene on metal oxides, the organic surface modifier re-engineered the interface of the metal oxide to improve charge transport. The energy level of ammonium anthracene increased the work function of indium tin oxide (ITO), functioning as a hole-blocker (electron-transporter). Solar cells in which ITO was treated by the ammonium anthracene produced an average power conversion efficiency (PCE) of 5.8% without ZnO, the electron-transporting layer. When the ammonium anthracene was applied to ZnO, an average PCE of 8.1% was achieved, which is higher than the average PCE of 7.5% for nontreated ZnO-based devices.

We have proposed the non-Abelian dual superconductivity picture for quark confinement in the SU(3) Yang-Mills (YM) theory, and have given numerical evidences for the restricted-field dominance and the non-Abelian magnetic monopole dominance in the string tension by applying a new formulation of the YM theory on a lattice. To establish the non-Abelian dual superconductivity picture for quark confinement, we have observed the non-Abelian dual Meissner effect in the SU(3) Yang-Mills theory by measuring the chromoelectric flux created by the quark-antiquark source, and the non-Abelian magnetic monopole currents induced around the flux. We conclude that the dual superconductivity of the SU(3) Yang-Mills theory is strictly the type I and that this type of dual superconductivity is reproduced by the restricted field and the non-Abelian magnetic monopole part, in sharp contrast to the SU(2) case: the border of type I and type II. [ABSTRACT FROM AUTHOR]

In a series of papers, we examine the physical unitarity in a massive Yang-Mills theory without the Higgs field in which the color gauge symmetry is not spontaneously broken and kept intact. For this purpose, we use a new framework proposed in the previous paper Kondo [arXiv: 1208.352 1] based on a nonperturbative construction of a non-Abelian field describing a massive spin-one vector boson field, which enables us to perform the perturbative and nonperturbative studies on the physical unitarity. In this paper, we present a new perturbative treatment for the physical unitarity after giving the general properties of the massive Yang-Mills theory. Then we reproduce the violation of physical unitarity in a transparent way. This paper is a preliminary work to the subsequent papers in which we present a nonperturbative framework to propose a possible scenario of restoring the physical unitarity in the Curci-Ferrari model. [ABSTRACT FROM AUTHOR]

In order to understand the so-called decoupling solution for gluon and ghost propagators in QCD, we give a nonperturbative construction of a massive vector field describing a non-Abelian massive spin-one particle, which has the correct physical degrees of freedom and is invariant under a modified Becchi-Rouet-Stora-Tyutin transformation, in a massive Yang-Mills model without the Higgs field, i.e., the Curci-Ferrari model. The resulting non-Abelian massive vector boson field is written by using a nonlinear but local transformation from the original fields in the Curci-Ferrari model. As an application, we write down a local mass term for the Yang-Mills field and a dimension-two condensate, which are exactly invariant under the modified Becchi-Rouet-Stora-Tyutin transformation, Lorentz transformation, and color rotation. [ABSTRACT FROM AUTHOR]

In our previous paper [N. Fukui, K.-I. Kondo, A. Shibata, and T. Shinohara, Phys. Rev. D 82, 045015 (2010)], we have shown that the Jackiw-Nohl-Rebbi (JNR) two-instanton generates a circular loop of magnetic monopole in the four-dimensional Euclidean SU(2) Yang-Mills theory. On the other hand, it is claimed in Brower et al. [Phys. Rev. D S5, 6313 (1997); Nucl. Phys. B, Proc. Suppl. 53, 488 (1997)] that the 't Hooft two-instanton does not generate magnetic monopole loop. It seems that the two results are inconsistent with each other, since the JNR two-instanton converges to the 't Hooft two-instanton in a certain limit. In this paper, we clarify that the two results are compatible with each other by demonstrating how the magnetic monopole loop generated from the JNR two-instanton deforms in the process of taking the 't Hooft two-instanton limit. [ABSTRACT FROM AUTHOR]

We give a theoretical framework for defining and extracting non-Abelian magnetic monopoles in a gauge-invariant way in SU(N) Yang-Mills theory to study quark confinement. Then we give numerical evidences that the non-Abelian magnetic monopole defined in this way gives a dominant contribution to confinement of fundamental quarks in SU(3) Yang-Mills theory, which is in sharp contrast to the SU(2) case in which Abelian magnetic monopoles play the dominant role for quark confinement. [ABSTRACT FROM AUTHOR]

ABSTRACTWe investigated the significance of endogenous reactive oxygen species (ROS) produced by fungi treated with miconazole. ROS production in Candida albicanswas measured by a real-time fluorogenic assay. The level of ROS production was increased by miconazole at the MIC (0.125 μg/ml) and was enhanced further in a dose-dependent manner, with a fourfold increase detected when miconazole was used at 12.5 μg/ml. This increase in the level of ROS production was completely inhibited by pyrrolidinedithiocarbamate (PDTC), an antioxidant, at 10 μM. In a colony formation assay, the decrease in cell viability associated with miconazole treatment was significantly prevented by addition of PDTC. Moreover, the level of ROS production by 10 clinical isolates of Candidaspecies was inversely correlated with the miconazole MIC (r= −0.8818; P< 0.01). These results indicate that ROS production is important to the antifungal activity of miconazole.

Extensive allelotyping studies have implicated several tumor-suppressor loci on chromosomes 3p, 5q, 6q, 8p, 9pq, 10q, 11q, 14q, 17p, 18q and 19p in human kidney tumorigenesis. The PTEN (also called MMAC1 and TEP1) gene, a candidate tumor suppressor located at chromosome 10q23.3, is mutated in a variety of sporadic malignancies as well as in patients with Cowden disease. To investigate the potential role of the PTEN gene in renal tumorigenesis, we searched for abnormalities of the gene in 68 primary renal-cell carcinomas (RCCs) as well as in 17 renal carcinoma–derived cell lines, using DNA-SSCP, sequencing and microsatellite analysis. Five of 68 (7.5%) primary RCCs exhibited intragenic mutations (3 missense, 1 deletion and 1 splice-site), and 1 of 17 (5.9%) cell lines had an insertion mutation. Loss of heterozygosity of the PTEN gene occurred in 25% of primary RCCs, including the 3 cases with intragenic mutation and the 1 PTEN-mutated cell line. Clinical and histopathological examinations revealed that 4 of the 5 primary tumors with PTEN mutation were high-grade, advanced clear-cell RCCs with distant metastases or renal vein tumor invasions, resulting in poor prognostic courses. The other was a low-stage papillary/chromophilic RCC. Our data suggest that PTEN mutation is observed in a subset of RCCs and that, especially in clear-cell RCCs, it occurs as a late-stage event and may contribute to the invasive and/or metastatic tumor phenotype. © 2001 Wiley-Liss, Inc.

We present rigorous correlation inequalities for connectedn-point functions in a class of even ferromagnets. The class includes spin-1/2 Ising models and scalar field models with potential functionV which is even and continuously differentiable withV' convex on [0, 8). These inequalities are obtained by pushing ahead with the method of Ellis, Monroe, and Newman at its maximum.

We investigated the effect of pranlukast (ONO-1078), a cysteinyl leukotriene receptor antagonist, in 11 patients with severe bronchial asthma. The patients had been treated with 1600 μg/day of beclomethasone or 800-1600 ug/day of beclomethasone plus 2.5-20 mg/day of prednisolone, but remained symptomatic. After a 2-week baseline period, the patients received 225 mg of pranlukast twice daily for 8 weeks. Morning and evening peak expiratory flow rate (PEF) and symptom scores (cough, dyspnea, sleep) were recorded in an asthma diary. Ten patients completed the study. Symptom scores, especially dyspnea and sleep scores, and the number of rescue β2-agonist inhalations were significantly decreased. The morning PEF significantly improved from a mean baseline value of 311 to 341 L/min by the end of the study period. The evening PEF also improved, from 328 to 348 L/min, although the difference was not significant. These results suggest that pranlukast may be effective in treating patients with severe asthma who are refractory to corticosteroid therapy.

Rigorous correlation inequalities are presented for a class of even ferromagnets, which includes the spin-1/2 Ising model and scalar ?4 models. One of them leads to an extension of the Glimm and Jaffe uniform upper bound on the ?4 renormalized coupling constant into the nonsymmetric regime.

We discuss the possible form of gluon and ghost propagators in the infrared region of Yang-Mills theory in the covariant gauge from the viewpoint of general principles of quantized gauge field theories. [Copyright &y& Elsevier]

We have found ultraviolet asymptotic slutions of the Schwinger-Dyson equation for the gluon and ghost propagators which have simultaneously the perturbative logarithmic correction and the non-perturbative SHAPE="SOL" ALIGN="C" STYLE="S">1p2 power correction. By including the perturbative corrections, the power correction reproduces exactly the leading OPE result suggesting the existence of dimension two condensate. [Copyright &y& Elsevier]

We give an outline of a recent proof that the low-energy effective gauge theory exhibiting quark confinement due to magnetic monopole condensation can be derived from QCD without any specific assumption. We emphasize that the low-energy effective abelian gauge theories obtained here give the dual description of the same physics in the low-energy region. They show that the QCD vacuum is nothing but the dual (type II) superconductor.

We present an introduction to the basic ideas of rigorous approaches to the quantum scalar field theories which are based on the statistical mechanical point of view. We also discuss several aspects of the rigorous studies in critical phenomena and phase transitions, and refer to some related open questions.

The phase structures of the abelian-Higgs model are analyzed, paying special attention to the difference between compact and non-compact formulation. The main purpose in this paper is to consider the meaning of confinement in the presence of matter fields and discuss what order parameters one should take to characterize the phases in view of confinement. We propose possible non-local order parameters which test the confinement-deconfinement transition. In addition, some recent developments of rigorous studies on related topics are reviewed.

We prove that the Faddeev-Popov ghost dressing function in the Yang-Mills theory is nonzero and finite in the limit of vanishing momenta and hence the ghost propagator behaves like the free propagator in the deep infrared regime, within the Gribov-Zwanziger framework of the D-dimensional SU(N) Yang-Mills theory in the Landau gauge for D > 2. This result implies that the Kugo-Ojima color confinement criterion is not satisfied in its original form. We point out that the result crucially depends on the explicit form of the nonlocal horizon term adopted. The original Gribov prediction in the Landau gauge should be reconsidered in connection with color confinement.

We propose a new version of SU(N) Yang-Mills theory reformulated in terms of new field variables which are obtained by a nonlinear change of variables from the original Yang-Mills gauge field. The reformulated Yang-Mills theory enables us to study the low-energy dynamics by explicitly extracting the topological degrees of freedom such as magnetic monopoles and vortices to clarify the mechanism for quark confinement. The dual superconductivity in Yang-Mills theory is understood in a gauge-invariant manner, as demonstrated recently by a non-Abelian Stokes theorem for the Wilson loop operator, although the basic idea of this reformulation is based on the Cho-Faddeev-Niemi decomposition of the gauge potential.

We give a new way of looking at the Cho-Faddeev-Niemi (CFN) decomposition of the Yang-Mills theory to answer how the enlarged local gauge symmetry respected by the CFN variables is restricted to obtain another Yang-Mills theory with the same local and global gauge symmetries as the original Yang-Mills theory. This may shed new light on the fundamental issue of the discrepancy between two theories for independent degrees of freedom and the role of the Maximal Abelian gauge in Yang-Mills theory. As a byproduct, this consideration gives new insight into the meaning of the gauge invariance and the observables, e.g., a gauge-invariant mass term and vacuum condensates of mass dimension two. We point out the implications for the Skyrme-Faddeev model.

We show that an effective Abelian gauge theory can be obtained as a renormalizable theory from QCD in the maximal Abelian gauge. The derivation improves in a systematic manner the previous version that was obtained by one of the authors and was referred to as the Abelian-projected effective gauge theory. This result supports the view that we can construct an effective Abelian gauge theory from QCD without losing characteristic features of the original non-Abelian gauge theory. In fact, it is shown that the effective coupling constant in the resulting renormalizable theory has a renormalization-scale dependence governed by the β-function that is exactly the same as that of the original Yang-Mills theory, irrespective of the choice of gauge fixing parameters of the maximal Abelian gauge and the parameters used for identifying the dual variables. Moreover, we evaluate the anomalous dimensions of the fields and parameters in the resultant theory. By choosing the renormalized parameters appropriately, we can switch the theory into an electric or a magnetic theory.

We derive a new version of the non-Abelian Stokes theorem for the Wilson loop in the SU(N) case by making use of the coherent state representation on the coset space SU(N)/U(1)N−1 = FN−1, the flag space. We consider the SU(N) Yang-Mills theory in the maximal Abelian gauge in which SU(N) is broken down to U(1)N−1. First, we show that the Abelian dominance in the string tension follows from this theorem and the Abelian-projected effective gauge theory that was derived by one of the authors. Next (but independently), combining the non-Abelian Stokes theorem with a novel reformulation of the Yang-Mills theory recently proposed by one of the authors, we proceed to derive the area law of the Wilson loop in four-dimensional SU(N) Yang-Mills theory in the maximal Abelian gauge. Owing to dimensional reduction, the planar Wilson loop at least for the fundamental representation in four-dimensional SU(N) Yang-Mills theory can be estimated by the diagonal (Abelian) Wilson loop defined in the two-dimensional CPN−1 model. This derivation shows that the fundamental quarks are confined by a single species of magnetic monopole. The origin of the area law is related to the geometric phase of the Wilczek-Zee holonomy for U(N−1). The calculations are performed using the instanton calculus (in the dilute instanton-gas approximation) and using the large N expansion (in the leading order).

We present a Euclidean lattice formulation of the Einstein-Cartan gravity. This formulation allows us to take any vale of the cosmological term. Moreover, this lattice theory is bounded and reflection positive, which leads to the existence of a positive Hilbert space and Hmiltonian, and hence unitarity in Minkowski space formulation. In the strong coupling region, cluster expansion converges and hence the infinite volume limit exists.

We show, apart from a correlation inequality for the 6-point function, that the critical or continuum limit of (ϕ4)4 lattice field theory is trivial, if some deviations from the mean field theory law are present at the critical point, and if we impose a mild behavior of bare 4-point coupling constant as we approach the critical point. These results are derived from the bounds on the renormalized coupling constant of lattice (ϕ4)d field theory.

Using weak and strong Yukawa coupling expansions combined with the mean field theory, we determine the phase structure of Yukawa models with Z(2), O(2), O(4) scalars. We have taken into account all the terms in the relevant expansions up to eighth order. In the leading order, all the Yukawa models have the four phases and do not possess the ferrimagnetic (FI) phase. This feature persists for Z(2) and O(2) Yukawa models to all orders. In the O(4) Yukawa model, on the other hand, the FI phase appears in the next to leading order and all higher orders, and two symmetric phases are completely separated by the FI phase. The result holds irrespective of the choice of fermions; naive or staggered.

In the leading order of the 1/N expansion for the vacuum polarization, we obtain the chiral-symmetry-breaking solutions of the Schwinger-Dyson equation in three-dimensional QED with N four-component Dirac fermions. Special attention is paid on the critical number of the fermion flavor Nc and the scaling law for the dynamical fermion mass. In this framework we introduce the infrared cutoff as well as the ultraviolet one. We show the relation between the vertex ansatz and the scaling law which is consistent with our numerical results that the scaling law is affected by the infrared cutoff. Especially in the case of the Pennington and Webb's vertex ansatz, the mean-field type scaling law and cutoff-dependent finite Nc are obtained in the large infrared cutoff, while the exponential type scaling and infinite Nc are given in the sufficiently small infrared cutoff. The connection with the Monte Carlo simulation is discussed.

Dynamical chiral-symmetry-breaking in massless QED with N fermion species is studied through the numerical solution of the coupled Schwinger-Dyson (SD) equation. We have taken into account the fermion loop effect (at the 1-loop level) in the SD equation for the photon propagator through the vacuum polarization function Π(k2), with and without the standard approximation: Π((p-q)2) ≈ Π(max (p2, q2)). We have found that the scaling law is unchanged by this approximation and that, irrespective of the fermion flavor N, the dynamical fermion mass and chiral order parameter obey the same mean-field type scaling, while the quenched planar QED without the vacuum polarization (N = 0 limit) obeys the Miransky scaling with the essential singularity.

Based on the Cornwall-Jackiw-Tomboulis effective potential, we extensively study nonperturbative renormalization of the gauged Nambu-Jona-Lasinio model in the ladder approximation with standing gauge coupling. Although the pure Nambu-Jona-Lasinio model is not renormalizable, presence of the gauge interaction makes it possible that the theory is renormalized as an interacting continuum theory at the critical line in the ladder approximation. Extra higher dimensional operators (“counter terms”) are not needed for the theory to be renormalized. By virtue of the effective potential approach, the renormalization (“symmetric renormalization”) is performed in a phase-independent manner both for the symmetric and the spontaneously broken phase of the chiral symmetry. We explicitly obtain β function having a nontrivial ultraviolet fixed line for the renormalized coupling as well as the bare one. In both phases the anomalous dimension is very large (≥1) without discontinuity across the fixed line. Operator product expansion is explicitly constructed, which is consistent with the large anomalous dimension owing to the appearance of the nontrivial extra power behavior in the Wilson coefficient for the unit operator. The symmetric renormalization breaks down at the critical gauge coupling, which is cured by the generalized renormalization scheme (“M-dependent renormalization”). Also emphasized is the formal resemblance to the four-fermion theory in less than four dimensions which is renomalizable in 1/N expansion.

Based on the ladder Schwinger-Dyson equation, we investigate phase structure of the gauged Yukawa model possessing a global SU(2)L ×SU(2)R symmetry and an unbroken (vector-like) gauge symmetry. We show that even when we tune the squared mass of the scalar boson in the Lagrangian to be positive, there still exists the dynamical chiral symmetry breaking due to fermion pair condensate (VEV of the composite scalar) triggered by the strong Yukawa coupling larger than a certain critical value. We find a “nontrivial ultraviolet fixed line” and “renormalized trajectories” in the three-dimensional coupling space of the Yukawa coupling, the gauge coupling and the “hopping parameter” of the elementary scalar field. Presence of the gauge coupling is crucial to existence of the fixed line. Implications of the result for the lattice calculation and the top quark condensate model are also discussed.

Prog. Theor. Phys. 91 (1994), 541. Equation (5.12) should read: Equation (5.13b) should read: with h(c) being the critical surface defined by Eq. (5.6). Figure captions for Figs. 1, 3 and 4 should be attached: Fig. 1 (Figure in page 550) Fig. 1. Graphical representation for the NG boson decay constant Fπ Eq. (3.4). Fig. 3 (upper figure in page 554) Fig. 3. Yukawa coupling dependence of the chiral condensate. The solid line, broken line, dashed line and dotted line correspond to Zφ=0.01, 0.1, 1, 10, respectively. Fig. 4 (left figure in page 554) Fig. 4. Critical line (bold line) and equi-ξf lines for Zφ = 0 (gauged NJL model) corresponding to ξf in Fig. 5. Publication Office

In the lattice U(1) gauge-Higgs model, we show the existence of mass gap by showing the exponential decay upper bound for the gauge-invariant two-point function. We construct the charged state as a non-localized (string-like) state and show its orthogonality to localized states in the QED phase.

We discuss the construction of the broken-symmetry λϕ4 theory from the lattice-regularized model defined on ɛZd (d-dimensional hypercubic lattice with lattice spacing ɛ) in the sense that the bare parameter (e.g., λ= λ(ɛ)) as a function of ɛ is adjusted approach the critical manifold Γc as ɛ↓0 such that limɛ→0 ≪ϕren(x) >(ɛ) ≠0. In the case of 0 ≪ limɛ→0 ≪ϕren(x)>(ɛ) ≪ ∞, it is shown that the 3- and 4-point renormalized coupling constant vanish in the continuum limit ɛ↓0, as long as 0 ≪ λ(ɛ) ≪ λ0 for sufficiently small λ0, in dimensions d > dc (upper critical dimension) where the critical exponent δ of the magnetization on the critical isotherm line takes its classical (mean-field) value δ= 3. Even for the renormalization which allows ≪ϕren(x) >(ɛ) →∞ as ɛ→0, the same type of triviality is derived for d > 4. These results suggest that the consistency requirement of the λϕ4 theory obtained in this scheme leads to the result: ≪ϕren(x)>(ɛ) →0 as ɛ→0, i.e., no breakdown of the symmetry ϕ→-ϕ in all d > 4 dimensions.

The triviality or non-triviality of the continuum limit of scalar field theories is studied based on the behavior of the dimensionless renormalized coupling constant. In d>4 dimensions, the triviality of the continuum theory constructed as the scaling limit of lattice scalar theories can be understood as the violation of the hyperscaling relations. From this point of view, we derive a number of critical exponent inequalities. As an immediate consequence of them, the renormalized 6-point coupling constant together with the 4-point one can be shown to vanish in d>4 dimensions.

We propose to use a novel master Lagrangian for performing the bosonization of the D-dimensional massive Thirring model in D = d + 1 ≥2 dimensions. It is shown that our master Lagrangian is able to relate the previous interpolating Lagrangians each other which have been recently used to show the equivalence of the massive Thirring model in (2 + 1) dimensions with the Maxwell-Chern-Simons theory. Starting from the phase-space path integral representation of the master Lagrangian, we give an alternative proof for this equivalence up to the next-to-leading order in the expansion of the inverse fermion mass. Moreover, in (3 + 1)-dimensional case, the bosonized theory is shown to be equivalent to the massive antisymmetric tensor gauge theory. As a byproduct, we reproduce the well-known result on bosonization of the (1 + 1)-dimensional Thirring model following the same strategy. Finally a possibility of extending our strategy to the non-Abelian case is also discussed.

We propose the gauged Thirring model as a natural gauge-invariant generalization of the Thirring model with a four-fermion interaction of current-current type. In the strong gauge-coupling limit, the gauged Thirring model reduces to the recently proposed reformulation of the Thirring model as a gauge theory. We pay special attention to the effect coming from the kinetic term for the gauge boson field which was originally the auxiliary field without the kinetic term. In 3 + 1 dimensions, we find nontrivial phase structure for the gauged Thirring model, based on the Schwinger-Dyson equation for the fermion propagator and a gauge-invariant effective potential for the chiral order parameter. Within this approximation, we study the renormalization group flows (lines of constant physics) and find a signal for nontrivial continuum limit with non-vanishing renormalized coupling constant and large anomalous dimension for the gauged Thirring model in 3+1 dimensions, at least for a small number of flavors Nf. Finally we discuss the (perturbatively) renormalizable extension of the gauged Thirring model.

We give an outline of a recent proof that the low-energy effective gauge theory exhibiting quark confinement due to magnetic monopole condensation can be derived from QCD without any specific assumption. We emphasize that the low-energy effective abelian gauge theories obtained here give the dual description of the same physics in the low-energy region. They show that the QCD vacuum is nothing but the dual (type II) superconductor.