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Purpose: The expression of the ETS-related gene (ERG) is low or undetectable in benign prostate epithelial cells. High prevalence of ERG overexpression in prostate cancer cells due to TMPRSS2-ERG fusions suggest for causal roles of ERG protein in the neoplastic process. TMPRSS2-ERG fusion junctions have been extensively studied in prostate cancer. However, virtually nothing is known about the nature of full-length transcripts and encoded proteins. This study focuses on qualitative and quantitative features of full-lengthTMPRSS2-ERG transcripts in prostate cancer. Experimental Design: Full-lengthTMPRSS2-ERG transcripts were cloned and sequenced from a cDNA library generated from pooled RNA of six TMPRSS2-ERG fusion^positive prostate tumors. The encoded ERG proteins were analyzed in HEK293 cells. Copy numbers of TMPRSS2-ERG splice variants were determined by quantitative reverse transcription-PCR in laser capture microdissected prostate cancer cells. Results: Two types of TMPRSS2-ERG cDNAs were identified: type I, which encodes full-length prototypical ERG protein (ERG1, ERG2, ERG3), and type II, encoding truncated ERG proteins lacking the ETS domain (ERG8 and a new variant,TEPC). In microdissected prostate tumor cells from 122 patients, relative abundance of these variants was in the following order: ERG8 > TEPC > ERG 3 > ERG1/2 with combined overexpression rate of 62.3% in prostate cancer. Increased ratio of type I over type II splice forms showed a trend of correlation with less favorable pathology and outcome.Conclusions: Qualitative and quantitative features of specific ERG splice variants defined here promise to enhance the utility of ERG as a biomarker and therapeutic target in prostate cancer.Molecular genetic evaluations of prostate cancer are defining mutational and expression alterations of critical oncogenes involved in disease onset and/or progression (reviewed in refs. 1 -3). Discovery of prevalent chromosomal rearrangements/ translocations leading to the activation of ETS transcription factors (predominantly ERG) through the androgen receptorregulated TMPRSS2 gene promoter underscore the critical roles of ERG-encoded protein in prostate cancer (4 -7). Because ERG represents the majority of TMPRSS2-ETS factor alterations described thus far (6, 7), we have focused on the expression and regulation of TMPRSS2-ERG in prostate cancer. Oncogenic functions of ETS factors, including ERG, have also been implicated in diverse cancers (8).Structure and function of ERG-encoded proteins remain to be defined in prostate cancer. ERG consists of 17 exons spanning about 300 kb and generates at least nine alternate splice forms, seven of them coding for protein products of varying sizes (9). These ERG splice variants have been primarily described in nonprostate tissues. Despite the large body of data on the TMPRSS2-ERG fusion junctions in prostate cancer (reviewed in refs. 6, 7), virtually nothing is known about the full-length TMPRSS2-ERG transcripts in prostate cancer, including the existence and relative a...

We consider a two-dimensional system initialized in a topologically trivial state before its Hamiltonian is ramped through a phase transition into a Chern insulator regime. This scenario is motivated by current experiments with ultracold atomic gases aimed at realizing time-dependent dynamics in topological insulators. Our main findings are twofold. First, considering coherent dynamics, the nonequilibrium Hall response is found to approach a topologically quantized time-averaged value in the limit of slow but nonadiabatic parameter ramps, even though the Chern number of the state remains trivial. Second, adding dephasing, the destruction of quantum coherence is found to stabilize this Hall response, while the Chern number generically becomes undefined. We provide a geometric picture of this phenomenology in terms of the time-dependent Berry curvature.

Although one-loop calculations provide a realistic description of bulk and single-particle nuclear properties, it is necessary to examine loop corrections to develop a systematic finite-density powercounting scheme for the nuclear many-body problem when loops are included. Moreover, it is imperative to study exchange and correlation corrections systematically to make reliable predictions for other nuclear observables. One must also verify that the natural sizes of the one-loop parameters are not destroyed by explicit inclusion of many-body corrections. The loop expansion is applied to a chiral effective hadronic lagrangian; with the techniques of Infrared Regularization, it is possible to separate out the short-range contributions and to write them as local products of fields that are already present in our lagrangian. (The appropriate field variables must be re-defined at each order in loops.) The corresponding parameters implicitly include short-range effects to all orders in the interaction, so these effects need not be calculated explicitly. The remaining (long-range) contributions that must be calculated are nonlocal and resemble those in conventional nuclear-structure calculations. Calculations at the two-loop level are carried out to illustrate these techniques at finite densities and to verify that the coupling parameters remain natural when fitted to the empirical properties of equilibrium nuclear matter.

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Robustness of edge states and non-Abelian excitations of topological states of matter promises quantum memory and quantum processing, which is naturally immune against microscopic imperfections such as static disorder. However, topological properties will not in general protect quantum system from time-dependent disorder or noise. Here we take the example of a network of Kitaev wires with Majorana edge modes storing qubits to investigate the effects of classical noise in the crossover from the quasi-static to the fast fluctuation regime. We present detailed results for the Majorana edge correlations, and fidelity of braiding operations for both global and local noise sources preserving parity symmetry, such as random chemical potentials and phase fluctuations. While in general noise will induce heating and dephasing, we identify examples of long-lived quantum correlations in presence of fast noise due to motional narrowing, where external noise drives the system rapidly between the topological and non-topological phases.

We show how dispersionless channels exhibiting perfect spin-momentum locking can arise in a 1D lattice model. While such spectra are forbidden by fermion doubling in static 1D systems, here we demonstrate their appearance in the stroboscopic dynamics of a periodically driven system. Remarkably, this phenomenon does not rely on any adiabatic assumptions, in contrast to the well known Thouless pump and related models of adiabatic spin pumps. The proposed setup is shown to be experimentally feasible with state of the art techniques used to control ultracold alkaline earth atoms in optical lattices.Introduction. Exploring the rich phenomenology of spin-orbit coupling is an active field of research in numerous branches of quantum physics [1][2][3]. The discovery of helical edge-states [4][5][6] has opened the route towards perfect spin-momentum locking, characterized by a oneto-one correspondence between the propagation direction of particles and their spin. Such exotic states have only been realized at the surface of 2D topological insulators [4,[7][8][9][10]. Without the 2D bulk, their occurrence is forbidden in 1D lattice systems [10], as the periodicity of band structures in the first Brillouin Zone (BZ) imposes fundamental constraints -referred to as fermion doubling [11] [cf. Fig. 1(a)]. Harnessing the unique properties of periodically driven quantum systems [12-17], here we show how these limitations can be circumvented: we find perfect spin-momentum locking in the stroboscopic dynamics of a periodically driven 1D lattice model. While conventional helical edge states require a time reversal symmetric topological 2D bulk [19], the spin-momentum locking in our 1D setting stems from topological properties in combined time-momentum (Floquet) space [see Fig. 1(d)], and relies on a spin-rotation symmetry of the stroboscopic dynamics. Our approach goes conceptually beyond adiabatically projected models such as the Thouless pump [20,21], in that we consider the full quasienergy spectrum without involving adiabatic projections.In Floquet systems, the quasi-energies are only defined modulo the driving frequency Ω, allowing for spectra that are only periodic in the BZ up to integer multiples of Ω. However, even in driven systems, unidirectional motion in 1D systems cannot be achieved without adiabatic assumptions, due to fundamental topological constraints [18]. The central result of this work is that the Floquet Bloch Hamiltonian ( = 1)

We identify emergent topological phenomena such as dynamic Chern numbers and dynamic quantum phase transitions in quantum quenches of the non-Hermitian Su-Schrieffer-Heeger Hamiltonian with parity-time (PT ) symmetry. Their occurrence in the non-unitary dynamics are intimately connected with fixed points in the Brillouin zone, where the states do not evolve in time. We construct a theoretical formalism for characterizing topological properties in non-unitary dynamics within the framework of biorthogonal quantum mechanics, and prove the existence of fixed points for quenches between distinct static topological phases in the PT -symmetry-preserving regime. We then reveal the interesting relation between different dynamic topological phenomena through the momentumtime spin texture characterizing the dynamic process. For quenches involving Hamiltonians in the PT -symmetry-broken regime, these topological phenomena are not ensured.The exploration of topological matter constitutes a major theme in modern physics [1,2]. With rapid progress in the discovery and understanding of topological phases in solid-state materials, a challenging quest lies in extending the study of conventional topological matter to novel regimes. Prominent examples include the investigation of emergent topological properties in out-of-equilibrium dynamics [3-28] and the characterization of topological phases in non-Hermitian systems [29? -40]. With the flexible controls afforded by synthetic systems such as ultracold atoms and engineered photonic configurations, the experimental implementation of these interesting scenarios is already within reach [41][42][43][44][45][46][47][48][49][50].An exemplary situation for the study of topological properties in out-of-equilibrium dynamics is the quantum quench of a topological system, where the ground state of the initial Hamiltonian H i is subject to a unitary time evolution governed by the final Hamiltonian H f . Whereas the topological invariant characterizing the instantaneous state is unchanged during the unitary dynamics [8,9], previous studies have revealed the emergence of intriguing phenomena such as dynamic quantum phase transitions (DQPTs) [13-18, 45, 51] and quantized non-equilibrium Hall responses in quench processes [19][20][21]. Further, in a series of recent theoretical and experimental studies, it has been established that dynamic topological invariants can be defined in unitary quantum quenches, which are related to the topology of initial and final Hamiltonians in equilibrium [23][24][25]44].Here arises an interesting question: what if the quench dynamics is non-unitary and governed by non-Hermitian Hamiltonians? The question is particularly relevant in light of recent studies on topological phenomena in parity-time(PT )-symmetric non-Hermitian systems [32][33][34][46][47][48]. Under PT symmetry, eigenenergies of a non-Hermitan Hamiltonian are entirely real in the PTsymmetry-preserving regime, in contrast to regimes with spontaneously broken PT symmetry [52][53][54]. Whereas it has be...