A
bstract
Symmetric mass generation is the name given to a mechanism for gapping fermions while preserving a chiral, but necessarily non-anomalous, symmetry. In this paper we describe how symmetric ...mass generation for continuous symmetries can be achieved using gauge dynamics in two and four dimensions. Various strong coupling effects are invoked, including known properties of supersymmetric gauge theories, specifically the phenomenon of s-confinement, and conjectured properties of non-supersymmetric chiral gauge theories.
A
bstract
There is an ambiguity in the gauge group of the Standard Model. The group is
G
= SU(3) × SU(2) × U(1)/Γ, where Γ is a subgroup of
Z
6
which cannot be determined by current experiments. We ...describe how the electric, magnetic and dyonic line operators of the theory depend on the choice of Γ. We also explain how the periodicity of the theta angles, associated to each factor of
G
, differ.
We show how particle-vortex duality in d=2+1 dimensions arises as part of an intricate web of relationships between different field theories. The starting point is “bosonization,” a conjectured ...duality that uses flux attachment to transmute the statistics of relativistic particles. From this seed, we derive many old and new dualities. These include particle-vortex duality for bosons as well as the recently discovered counterpart for fermions.
A
bstract
We study boundary states for Dirac fermions in
d
= 1 + 1 dimensions that preserve Abelian chiral symmetries, meaning that the left- and right-moving fermions carry different charges. We ...derive simple expressions, in terms of the fermion charge assignments, for the boundary central charge and for the ground state degeneracy of the system when two different boundary conditions are imposed at either end of an interval. We show that all such boundary states fall into one of two classes, related to SPT phases supported by (
−
1)
F
, which are characterised by the existence of an unpaired Majorana zero mode.
In principle, there is no obstacle to gapping fermions preserving any global symmetry that does not suffer a ’t Hooft anomaly. In practice, preserving a symmetry that is realized on fermions in a ...chiral manner necessitates some dynamics beyond simple quadratic mass terms. We show how this can be achieved using familiar results about the strong coupling dynamics of supersymmetric gauge theories and, in particular, the phenomenon of confinement without chiral symmetry breaking. We present simple models that gap fermions while preserving a symmetry group under which they transform in chiral representations. For example, we show how to gap a collection of 4D fermions that carry the quantum numbers of one generation of the standard model, but without breaking electroweak symmetry. We further show how to gap fermions in groups of 16 while preserving certain discrete symmetries that exhibit a mod 16 anomaly.
Excess accumulation of advanced glycation end products (AGEs) contributes to aging and chronic diseases. We aimed to obtain evidence that exposure to AGEs plays a role in the development of type 1 ...diabetes (T1D).
The effect of AGEs was examined on insulin secretion by MIN6N8 cells and mouse islets and in vivo in three separate rodent models: AGE-injected or high AGE-fed Sprague-Dawley rats and nonobese diabetic (NODLt) mice. Rodents were also treated with the AGE-lowering agent alagebrium.
β-Cells exposed to AGEs displayed acute glucose-stimulated insulin secretory defects, mitochondrial abnormalities including excess superoxide generation, a decline in ATP content, loss of MnSOD activity, reduced calcium flux, and increased glucose uptake, all of which were improved with alagebrium treatment or with MnSOD adenoviral overexpression. Isolated mouse islets exposed to AGEs had decreased glucose-stimulated insulin secretion, increased mitochondrial superoxide production, and depletion of ATP content, which were improved with alagebrium or with MnTBAP, an SOD mimetic. In rats, transient or chronic exposure to AGEs caused progressive insulin secretory defects, superoxide generation, and β-cell death, ameliorated with alagebrium. NODLt mice had increased circulating AGEs in association with an increase in islet mitochondrial superoxide generation, which was prevented by alagebrium, which also reduced the incidence of autoimmune diabetes. Finally, at-risk children who progressed to T1D had higher AGE concentrations than matched nonprogressors.
These findings demonstrate that AGEs directly cause insulin secretory defects, most likely by impairing mitochondrial function, which may contribute to the development of T1D.
The p53 tumor suppressor is a transcription factor (TF) that exerts antitumor functions through its ability to regulate the expression of multiple genes. Within the p53 protein resides a relatively ...short unstructured C-terminal domain (CTD) that remarkably participates in virtually every aspect of p53 performance as a TF. Because these aspects are often interdependent and it is not always possible to dissect them experimentally, there has been a great deal of controversy about the CTD. In this review we evaluate the significance and key features of this interesting region of p53 and its impact on the many aspects of p53 function in light of previous and more recent findings.
p53 is a TF that exerts its antitumor activity predominantly through the transcriptional regulation of multiple target genes.
Rapid identification of cognate p53 sites within the chromatin context of the eukaryotic cell, stable sequence-specific DNA binding, and cofactor recruitment are vital for an accurate and efficient transcriptional outcome mediated by p53 in response to a variety of stimuli of exogenous and endogenous nature.
The intrinsically disordered CTD participates in all aspects of p53 functioning as a TF.
Lack of structural constraints, conformational dynamics, and a unique amino acid composition are important for functions of the CTD within p53.
Despite the current lack of structural information on the CTD within p53, the CTD is an integral part of the tetramer and participates in its binding-induced structural changes.
A
bstract
We study the dynamics of chiral SU(
N
) gauge theories. These contain Weyl fermions in the symmetric or anti-symmetric representation of the gauge group, together with further fermions in ...the fundamental and anti-fundamental. We revisit an old proposal of Bars and Yankielowicz who match the ‘t Hooft anomalies of this theory to free fermions. We show that there are novel and, in some cases, quite powerful constraints on the dynamics in the large
N
limit.
In addition, we study these SU(
N
) theories with an extra Weyl fermion transforming in the adjoint representation. Here we show that all 21 ‘t Hooft anomalies for global symmetries are matched with those of a Spin(8) gauge theory. This suggests a non-supersymmetric extension of the duality of Pouliot and Strassler. Finally, we also discuss some non-supersymmetric dualities with vector-like matter content for SO(
N
) and Sp(
N
) gauge theories and the constraints imposed by Weingarten inequalities.
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