Geometric frustration in two-dimensional Ising models allows for a wealth of exotic universal behavior, both Ising and non-Ising, in the presence of quantum fluctuations. In particular, the triangular antiferromagnet and Villain model in a transverse field can be understood through distinct XY pseudospins, but have qualitatively similar phase diagrams including a quantum phase transition in the (2+1)-dimensional XY universality class. While the quantum dynamics of modestly-sized systems can be simulated classically using tensor-based methods, these methods become infeasible for larger lattices.
View Article and Find Full Text PDFMass coral bleaching on the Great Barrier Reef (GBR) in Australia between 2016 and 2024 was driven by high sea surface temperatures (SST). The likelihood of temperature-induced bleaching is a key determinant for the future threat status of the GBR, but the long-term context of recent temperatures in the region is unclear. Here we show that the January-March Coral Sea heat extremes in 2024, 2017 and 2020 (in order of descending mean SST anomalies) were the warmest in 400 years, exceeding the 95th-percentile uncertainty limit of our reconstructed pre-1900 maximum.
View Article and Find Full Text PDFFluctuations may induce the degradation of order by overcoming ordering interactions, consequently leading to an increase of entropy. This is particularly evident in magnetic systems characterized by nontrivial, constrained disorder, where thermal or quantum fluctuations can yield counterintuitive forms of ordering. Using the proven efficiency of quantum annealers as programmable spin system simulators, we present a study based on entropy postulates and experiments on a platform of programmable superconducting qubits to show that a low level of uncertainty can promote ordering in a system impacted by both thermal and quantum fluctuations.
View Article and Find Full Text PDFOver the past decade, Next-Generation Sequencing (NGS) has advanced our understanding, diagnosis, and management of several areas within dermatology. NGS has emerged as a powerful tool for diagnosing genetic diseases of the skin, improving upon traditional PCR-based techniques limited by significant genetic heterogeneity associated with these disorders. Epidermolysis bullosa and ichthyosis are two of the most extensively studied genetic diseases of the skin, with a well-characterized spectrum of genetic changes occurring in these conditions.
View Article and Find Full Text PDFThe relationships between crop productivity and climate variability drivers are often assumed to be stationary over time. However, this may not be true in a warming climate. Here we use a crop model and a machine learning algorithm to demonstrate the changing impacts of climate drivers on wheat productivity in Australia.
View Article and Find Full Text PDFExperiments on disordered alloys suggest that spin glasses can be brought into low-energy states faster by annealing quantum fluctuations than by conventional thermal annealing. Owing to the importance of spin glasses as a paradigmatic computational testbed, reproducing this phenomenon in a programmable system has remained a central challenge in quantum optimization. Here we achieve this goal by realizing quantum-critical spin-glass dynamics on thousands of qubits with a superconducting quantum annealer.
View Article and Find Full Text PDFNodular melanoma (NM) is the third most common subtype of melanoma among African Americans trailing behind acral lentiginous melanoma and superficial spreading melanoma. This case of NM in an African American Japanese male was selected due to the rare occurrence of NM in people of color.
View Article and Find Full Text PDFNat Commun
February 2023
Topological phases of spin liquids with constrained disorder can host a kinetics of fractionalized excitations. However, spin-liquid phases with distinct kinetic regimes have proven difficult to observe experimentally. Here we present a realization of kagome spin ice in the superconducting qubits of a quantum annealer, and use it to demonstrate a field-induced kinetic crossover between spin-liquid phases.
View Article and Find Full Text PDFArtificial spin ices are frustrated spin systems that can be engineered, in which fine tuning of geometry and topology has allowed the design and characterization of exotic emergent phenomena at the constituent level. Here, we report a realization of spin ice in a lattice of superconducting qubits. Unlike conventional artificial spin ice, our system is disordered by both quantum and thermal fluctuations.
View Article and Find Full Text PDFThe promise of quantum computing lies in harnessing programmable quantum devices for practical applications such as efficient simulation of quantum materials and condensed matter systems. One important task is the simulation of geometrically frustrated magnets in which topological phenomena can emerge from competition between quantum and thermal fluctuations. Here we report on experimental observations of equilibration in such simulations, measured on up to 1440 qubits with microsecond resolution.
View Article and Find Full Text PDFThe mechanism underlying frontal fibrosing alopecia (FFA) is unknown, but proposed mechanisms share commonality of T cell-mediated destruction of the hair follicle bulge. IL-12 and IL-23 are key cytokines involved in CD4 T cell differentiation towards Th1 and Th17 phenotypes. We present a 62-year-old woman who developed persistent FFA while on ustekinumab for treatment of preexisting psoriasis.
View Article and Find Full Text PDFThe work of Berezinskii, Kosterlitz and Thouless in the 1970s revealed exotic phases of matter governed by the topological properties of low-dimensional materials such as thin films of superfluids and superconductors. A hallmark of this phenomenon is the appearance and interaction of vortices and antivortices in an angular degree of freedom-typified by the classical XY model-owing to thermal fluctuations. In the two-dimensional Ising model this angular degree of freedom is absent in the classical case, but with the addition of a transverse field it can emerge from the interplay between frustration and quantum fluctuations.
View Article and Find Full Text PDFDNA methylation is one of a number of modes of epigenetic gene regulation. Here, we profile the DNA methylome, transcriptome, and global occupancy of histone modifications (H3K4me1, H3K4me3, H3K27me3, and H3K27ac) in a series of mouse embryonic stem cells (mESCs) with varying DNA methylation levels to study the effects of DNA methylation on deposition of histone modifications. We find that genome-wide DNA demethylation alters occupancy of histone modifications at both promoters and enhancers.
View Article and Find Full Text PDFThe electrochemical impedance of reactive metals such as magnesium is often complicated by an obvious inductive loop with decreasing frequency of the AC polarising signal. The characterisation and ensuing explanation of this phenomenon has been lacking in the literature to date, being either ignored or speculated. Herein, we couple electrochemical impedance spectroscopy (EIS) with online atomic emission spectroelectrochemistry (AESEC) to simultaneously measure Mg-ion concentration and electrochemical impedance spectra during Mg corrosion, in real time.
View Article and Find Full Text PDFGraph theory analysis of biological networks, such as protein-protein interactions (PPIs), gene regulatory, metabolic, etc., has identified a strong relationship between topology of these networks and the underlying cellular function and biological processes (Sharan et al. Mol Syst Biol 3:88, 2007).
View Article and Find Full Text PDFThis paper reports a microfluidic device capable of generating oxygen gradients for cell culture using spatially confined chemical reactions with minimal chemical consumption. The microfluidic cell culture device is constructed by single-layer polydimethylsiloxane (PDMS) microfluidic channels, in which the cells can be easily observed by microscopes. The device can control the oxygen gradients without the utilization of bulky pressurized gas cylinders, direct addition of oxygen scavenging agents, or tedious gas interconnections and sophisticated flow control.
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