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The key haematopoietic regulator Myb is essential for coordinating proliferation and differentiation. ChIP‐Sequencing and Chromosome Conformation Capture (3C)‐Sequencing were used to characterize the structural and protein‐binding dynamics of the Myb locus during erythroid differentiation. In proliferating cells expressing Myb , enhancers within the Myb ‐ Hbs1l intergenic region were shown to form an active chromatin hub (ACH) containing the Myb promoter and first intron. This first intron was found to harbour the transition site from transcription initiation to elongation, which takes place around a conserved CTCF site. Upon erythroid differentiation, Myb expression is downregulated and the ACH destabilized. We propose a model for Myb activation by distal enhancers dynamically bound by KLF1 and the GATA1/TAL1/LDB1 complex, which primarily function as a transcription elongation element through chromatin looping. The transcription factor c‐Myb plays an important role in the differentiation of haematopoietic stem cells. This study describes the changes in the organization of the Myb gene locus during erythroid differentiation and uncovers a role of the intronic binding site for CTCF in the transition from transcriptional initiation to elongation.

The fruitful functional performances of metastable Heusler alloys originate from the martensitic transformation driven by the transverse acoustic soft phonon mode, regulated by anharmonicity. However, the origins of the soft mode and the anharmonicity in these alloys remain unclear. In this work, using ab‐initio calculations combined with self‐consistent phonon theory (SCPH) and compressed sensing techniques in machine learning, a link among chemical bonding, long‐range interaction, soft mode, and anharmonicity is established using Ni2MnGa as a model system. The long‐range interaction rooted in metallic bonding between spin‐down d‐orbitals of Ni─Ni induces phonon softening and significant anharmonicity. This finding offers new insights into the role of metallic bonding and long‐range interactions in martensitic transformation, providing a fresh perspective for the design and optimization of phase transition functional alloys. The fruitful functional performances of metastable Heusler alloys originate from the martensitic transformation driven by the transverse acoustic soft phonon mode, regulated by anharmonicity. This study reveals that the long‐range interaction rooted in metallic bonding between spin‐down d‐orbitals of Ni─Ni induces phonon softening and significant anharmonicity, which provides a fresh perspective for the design and optimization of phase transition functional alloys.

We consider here a problem of population dynamics modeled on a logistic equation with both classical and nonlocal diffusion, possibly in combination with a pollination term. The environment considered is a niche with zero-flux, according to a new type of Neumann condition. We discuss situations that are more favorable for the survival of the species, in terms of the first positive eigenvalue. Quite surprisingly, the eigenvalue analysis for the one-dimensional case is structurally different from the higher-dimensional setting, and it sensibly depends on the nonlocal character of the dispersal.The mathematical framework of this problem takes into consideration the equation−αΔu+β(−Δ)su=(m−μu)u+τJ⋆u in Ω,where m can change sign. This equation is endowed with a set of Neumann conditions that combines the classical normal derivative prescription and the nonlocal condition introduced in Dipierro, Ros-Oton, and Valdinoci [Rev. Mat. Iberoam. 33 (2017), 377–416]. We will establish the existence of a minimal solution for this problem and provide a thorough discussion on whether it is possible to obtain nontrivial solutions (corresponding to the survival of the population).The investigation will rely on a quantitative analysis of the first eigenvalue of the associated problem and on precise asymptotics for large lower and upper bounds of the resource. In this, we also analyze the role played by the optimization strategy in the distribution of the resources, showing concrete examples that are unfavorable for survival, in spite of the large resources that are available in the environment.

Long-lived quasi-stationary states (QSSs) are a signature characteristic of long-range interacting systems both in the classical and in the quantum realms. Often, they emerge after a sudden quench of the Hamiltonian internal parameters and present a macroscopic lifetime, which increases with the system size. Despite their ubiquity, the fundamental mechanism at their root remains unknown. Here, we show that the spectrum of systems with power-law decaying couplings remains discrete up to the thermodynamic limit. As a consequence, several traditional results on the chaotic nature of the spectrum in many-body quantum systems are not satisfied in the presence of long-range interactions. In particular, the existence of QSSs may be traced back to the finiteness of Poincaré recurrence times. This picture justifies and extends known results on the anomalous magnetization dynamics in the quantum Ising model with power-law decaying couplings. The comparison between the discrete spectrum of long-range systems and more conventional examples of pure point spectra in the disordered case is also discussed.

Background Most DNA cancer methylation markers are based on the transcriptional regulation of the promoter-gene relationship. Recently, the importance of long-range interactions between distal CpGs and target genes has been revealed. Here, we attempted to identify methylation markers for breast cancer that interact with distant genes. Results We performed integrated analysis using chromatin interactome data, methylome data, transcriptome data, and clinical information for breast cancer from public databases. Using the chromatin interactome and methylome data, we defined CpG-distant target gene relationships. After determining the differences in methylation between tumor and paired normal samples, the survival association, and the correlation between CpG methylation and distant target gene expression, we selected CpG methylation marker candidates. Using Cox proportional hazards models, we combined the selected markers and evaluated the prognostic model. We identified six methylation markers in HOXA9 and HOXA10 promoter regions and their long-range target genes. We experimentally validated the chromatin interactions, methylation status, and transcriptional regulation. A prognostic model showed that the combination of six methylation markers was highly associated with poor survival in independent datasets. According to our multivariate analysis, the prognostic model showed significantly better prognostic ability than other histological and molecular markers. Conclusions The combination of long-range interacting HOXA9 and HOXA10 promoter CpGs predicted the survival of breast cancer patients, providing a comprehensive and novel approach for discovering new methylation markers.

Long-range interacting quantum devices provides a promising route for quantum technology applications. Here, the presence of long-range interactions is shown to enhance the performances of a quantum heat engine featuring a many-body working substance. We focus on the paradigmatic example of a Kitaev chain undergoing a quantum Otto cycle and show that a substantial thermodynamic advantage may be achieved as the range of the interactions among its constituents increases. The advantage is most significant for the realistic situation of a finite time cycle: the presence of long-range interactions reduces the non-adiabatic energy losses, by suppressing the detrimental effects of dynamically generated excitations. This effect allows mitigating the trade-off between power and efficiency, paving the way for a wide range of experimental and technological applications.

Oestrogen receptor α (ERα) is key player in the progression of breast cancer. Recently, the cistrome and interactome of ERα were mapped in breast cancer cells, revealing the importance of spatial organization in oestrogen‐mediated transcription. However, the underlying mechanism of this process is unclear. Here, we show that ERα binding sites (ERBS) identified from the Chromatin Interaction Analysis‐Paired End DiTag of ERα are enriched for AP‐2 motifs. We demonstrate the transcription factor, AP‐2γ, which has been implicated in breast cancer oncogenesis, binds to ERBS in a ligand‐independent manner. Furthermore, perturbation of AP‐2γ expression impaired ERα DNA binding, long‐range chromatin interactions, and gene transcription. In genome‐wide analyses, we show that a large number of AP‐2γ and ERα binding events converge together across the genome. The majority of these shared regions are also occupied by the pioneer factor, FoxA1. Molecular studies indicate there is functional interplay between AP‐2γ and FoxA1. Finally, we show that most ERBS associated with long‐range chromatin interactions are colocalized with AP‐2γ and FoxA1. Together, our results suggest AP‐2γ is a novel collaborative factor in ERα‐mediated transcription. It remains unclear how the spatial organization of the genome contributes to gene expression. Here, AP‐2 is identified as a new collaborative factor for the oestrogen receptor and it is important for the recruitment of the receptor, FoxA1, long‐range genome interactions, and gene transcription.

We induce strong nonlocal interactions in a 2D Fermi gas in an optical lattice using Rydberg dressing. The system is approximately described by a model on a square lattice where the fermions experience isotropic nearest-neighbor interactions and are free to hop only along one direction. We measure the interactions using many-body Ramsey interferometry and study the lifetime of the gas in the presence of tunneling, finding that tunneling does not reduce the lifetime. To probe the interplay of nonlocal interactions with tunneling, we investigate the short-time-relaxation dynamics of charge-density waves in the gas. We find that strong nearest-neighbor interactions slow down the relaxation. Our work opens the door for quantum simulations of systems with strong nonlocal interactions such as extended Fermi-Hubbard models.

In the present paper, we examine Ising systems on d-dimensional hypercube lattices and solve an inverse problem where we have to determine interaction constants of an Ising connection matrix when we know a spectrum of its eigenvalues. In addition, we define restrictions allowing a random number sequence to be a connection matrix spectrum. We use the previously obtained analytical expressions for the eigenvalues of Ising connection matrices accounting for an arbitrary long-range interaction and supposing periodic boundary conditions.

We analyze the quantum phases, correlation functions and edge modes for a class of spin-1/2 and fermionic models related to the one-dimensional Ising chain in the presence of a transverse field. These models are the Ising chain with anti-ferromagnetic long-range interactions that decay with distance r as , as well as a related class of fermionic Hamiltonians that generalize the Kitaev chain, where both the hopping and pairing terms are long-range and their relative strength can be varied. For these models, we provide the phase diagram for all exponents , based on an analysis of the entanglement entropy, the decay of correlation functions, and the edge modes in the case of open chains. We demonstrate that violations of the area law can occur for , while connected correlation functions can decay with a hybrid exponential and power-law behavior, with a power that is -dependent. Interestingly, for the fermionic models we provide an exact analytical derivation for the decay of the correlation functions at every . Along the critical lines, for all models breaking of conformal symmetry is argued at low enough . For the fermionic models we show that the edge modes, massless for , can acquire a mass for . The mass of these modes can be tuned by varying the relative strength of the kinetic and pairing terms in the Hamiltonian. Interestingly, for the Ising chain a similar edge localization appears for the first and second excited states on the paramagnetic side of the phase diagram, where edge modes are not expected. We argue that, at least for the fermionic chains, these massive states correspond to the appearance of new phases, notably approached via quantum phase transitions without mass gap closure. Finally, we discuss the possibility to detect some of these effects in experiments with cold trapped ions.