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Abstract The remarkable complexity of a topologically ordered many-body quantum system is encoded in the characteristics of its anyons. Quintessential predictions emanating from this complexity employ the Fibonacci string net condensate (Fib SNC) and its anyons: sampling Fib-SNC would estimate chromatic polynomials while exchanging its anyons would implement universal quantum computation. However, physical realizations remained elusive. We introduce a scalable dynamical string net preparation (DSNP) that constructs Fib SNC and its anyons on reconfigurable graphs suitable for near-term superconducting processors. Coupling the DSNP approach with composite error-mitigation on deep circuits, we create, measure, and braids Fibonacci anyons; charge measurements show 94% accuracy, and exchanging the anyons yields the expected golden ratioϕwith 98% average accuracy. We then sample the Fib SNC to estimate chromatic polynomial atϕ + 2 for several graphs. Our results establish the proof of principle for using Fib-SNC and its anyons for fault-tolerant universal quantum computation and aim at a classically hard problem. 

Calling context is crucial for improving the precision of program analyses in various use cases (clients), such as profiling, debugging, optimization, and security checking. Often the calling context is encoded using a numerical value. We have observed that many clients benefit not only from a deterministic but also globally distinguishable value across runs to simplify bookkeeping and guarantee complete uniqueness. However, existing work only guarantees determinism, not global distinguishability. Clients need to develop auxiliary helpers, which incurs considerable overhead to distinguish encoded values among all calling contexts. In this paper, we propose Deterministic Distinguishable Calling Context Encoding () that can enable both properties of calling context encoding natively. The key idea of is leveraging the static call graph and encoding each calling context as the running call path count. Thereby, a mapping is established statically and can be readily used by the clients. Our experiments with two client tools show that has a comparable overhead compared to two state-of-the-art encoding schemes, PCCE and PCC, and further avoids the expensive overheads of collision detection, up to 2.1× and 50%, for Splash-3 and SPEC CPU 2017, respectively. 

Abstract We studied translation factor eukaryotic initiation factor 4E (eIF4E) paralogs that regulate germline mRNAs. Translational control of mRNAs is essential for germ cell differentiation and embryogenesis. Messenger ribonucleoprotein complexes assemble on mRNAs in the nucleus, as they exit via perinuclear germ granules, and in the cytoplasm. Bound messenger ribonucleoproteins including eIF4E exert both positive and negative posttranscriptional regulation. In Caenorhabditiselegans, germ granules are surprisingly dynamic messenger ribonucleoprotein condensates that remodel during development. Two eIF4E paralogs (IFE-1 and IFE-3), their cognate eIF4E–interacting proteins, and polyadenylated mRNAs are present in germ granules. Affinity purification of IFE-1 and IFE-3 messenger ribonucleoproteins allowed mass spectrometry and mRNA-Seq to identify other proteins and the mRNAs that populate stable eukaryotic initiation factor 4E complexes. We find translationally repressed mRNAs (e.g. pos-1, mex-3, spn-4, etc.) enriched with IFE-3, but excluded from IFE-1. Identified mRNAs overlap substantially with mRNAs previously described to be IFE-1 dependent for translation. The findings suggest that oocytes and embryos utilize the 2 eukaryotic initiation factor 4E paralogs for opposite purposes on critically regulated germline mRNAs. Sublocalization within adult perinuclear germ granules suggests an architecture in which Vasa/GLH-1, PGL-1, and the IFEs are stratified, which may facilitate sequential remodeling of messenger ribonucleoproteins leaving the nucleus. Biochemical composition of isolated messenger ribonucleoproteins indicates opposing yet cooperative roles for the 2 eukaryotic initiation factor 4E paralogs. We propose that the IFEs accompany controlled mRNAs in the repressed or activated state during transit to the cytoplasm. Copurification of IFE-1 with IFE-3 suggests they may interact to move repressed mRNAs to ribosomes. 

This manuscript presents high-throughput sorting of cellular-sized microparticles within a three-dimensional microfluidic channel by focused bulk acoustic wave (BAW) produced by a Self-Focusing Acoustic Transducer (SFAT). The focused ultrasound induces a substantially higher acoustic radiation force within the focal region, enabling sorting based on particle size and density. Unlike surface-acoustic-wave-based setups, the BAW-based technique uses a three-dimensional microfluidic channel through which a mixture of particles is transported, while SFAT(s) may be placed at multiple points along the channel for multi-stage sorting. The technique has been successfully used in sorting 50 μm microparticles, which are analogous to cancerous or differentiated Mesenchymal Stem Cells (MSC), from 30 μm microparticles, which are analogous to healthy MSC. The sorting results in 97.5% purity at the smaller microparticle outlet and a 97.2% recovery rate for the smaller particles. The technique allows sorting 650,000 smaller and 142,000 larger microparticles within a mere 10 minutes. 

Cellular identity and fate are determined by the proteins synthesized. Initiation of mRNA translation requires an important translation factor, eIF4G (ifg-1 in C. elegans). Embryos use mRNA translational control for spatial and temporal regulation of protein synthesis. Using CRISPR engineering, we added in-frame epitope and fluorescent tags (V5, Myc, Flag, GFP, and mCherry) to IFG-1. Tagged forms containing the V5 epitope caused embryonic arrest. Internal disruption of the V5 tag restored viability at 25°C. This study demonstrates that the molecular nature of a small epitope tag is sufficient to disrupt C. elegans embryogenesis. 

Large language models (LLMs) have demonstrated abilities to perform complex tasks in multiple domains, including mathematical and scientific reasoning. We demonstrate that with carefully designed prompts, LLMs can accurately carry out key calculations in research papers in theoretical physics. We focus on a broadly-used approximation method in quantum physics: the Hartree-Fock method, requiring an analytic multi-step calculation deriving approximate Hamiltonian and corresponding self-consistency equations. To carry out the calculations using LLMs, we design multi-step prompt templates that break down the analytic calculation into standardized steps with placeholders for problem-specific information. We evaluate GPT-4’s performance in executing the calculation for 15 papers from the past decade, demonstrating that, with the correction of intermediate steps, it can correctly derive the final Hartree-Fock Hamiltonian in 13 cases. Aggregating across all research papers, we find an average score of 87.5 (out of 100) on the execution of individual calculation steps. We further use LLMs to mitigate the two primary bottlenecks in this evaluation process: (i) extracting information from papers to fill in templates and (ii) automatic scoring of the calculation steps, demonstrating good results in both cases. 

Abstract With rapid progress in simulation of strongly interacting quantum Hamiltonians, the challenge in characterizing unknown phases becomes a bottleneck for scientific progress. We demonstrate that a Quantum-Classical hybrid approach (QuCl) of mining sampled projective snapshots with interpretable classical machine learning can unveil signatures of seemingly featureless quantum states. The Kitaev-Heisenberg model on a honeycomb lattice under external magnetic field presents an ideal system to test QuCl, where simulations have found an intermediate gapless phase (IGP) sandwiched between known phases, launching a debate over its elusive nature. We use the correlator convolutional neural network, trained on labeled projective snapshots, in conjunction with regularization path analysis to identify signatures of phases. We show that QuCl reproduces known features of established phases. Significantly, we also identify a signature of the IGP in the spin channel perpendicular to the field direction, which we interpret as a signature of Friedel oscillations of gapless spinons forming a Fermi surface. Our predictions can guide future experimental searches for spin liquids.