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A look at the American artist Jeremiah Goodman's work capturing professionally designed interiors in his paintings.

Scalable quantum computing can become a reality with error correction, provided that coherent qubits can be constructed in large arrays 1 , 2 . The key premise is that physical errors can remain both small and sufficiently uncorrelated as devices scale, so that logical error rates can be exponentially suppressed. However, impacts from cosmic rays and latent radioactivity violate these assumptions. An impinging particle can ionize the substrate and induce a burst of quasiparticles that destroys qubit coherence throughout the device. High-energy radiation has been identified as a source of error in pilot superconducting quantum devices 3 – 5 , but the effect on large-scale algorithms and error correction remains an open question. Elucidating the physics involved requires operating large numbers of qubits at the same rapid timescales necessary for error correction. Here, we use space- and time-resolved measurements of a large-scale quantum processor to identify bursts of quasiparticles produced by high-energy rays. We track the events from their initial localized impact as they spread, simultaneously and severely limiting the energy coherence of all qubits and causing chip-wide failure. Our results provide direct insights into the impact of these damaging error bursts and highlight the necessity of mitigation to enable quantum computing to scale. Cosmic rays flying through superconducting quantum devices create bursts of excitations that destroy qubit coherence. Rapid, spatially resolved measurements of qubit error rates make it possible to observe the evolution of the bursts across a chip.

Scalable quantum computing can become a reality with error correction, provided coherent qubits can be constructed in large arrays. The key premise is that physical errors can remain both small and sufficiently uncorrelated as devices scale, so that logical error rates can be exponentially suppressed. However, energetic impacts from cosmic rays and latent radioactivity violate both of these assumptions. An impinging particle ionizes the substrate, radiating high energy phonons that induce a burst of quasiparticles, destroying qubit coherence throughout the device. High-energy radiation has been identified as a source of error in pilot superconducting quantum devices, but lacking a measurement technique able to resolve a single event in detail, the effect on large scale algorithms and error correction in particular remains an open question. Elucidating the physics involved requires operating large numbers of qubits at the same rapid timescales as in error correction, exposing the event's evolution in time and spread in space. Here, we directly observe high-energy rays impacting a large-scale quantum processor. We introduce a rapid space and time-multiplexed measurement method and identify large bursts of quasiparticles that simultaneously and severely limit the energy coherence of all qubits, causing chip-wide failure. We track the events from their initial localised impact to high error rates across the chip. Our results provide direct insights into the scale and dynamics of these damaging error bursts in large-scale devices, and highlight the necessity of mitigation to enable quantum computing to scale.

Realizing the potential of quantum computing will require achieving sufficiently low logical error rates. Many applications call for error rates in the \\(10^-15\\) regime, but state-of-the-art quantum platforms typically have physical error rates near \\(10^-3\\). Quantum error correction (QEC) promises to bridge this divide by distributing quantum logical information across many physical qubits so that errors can be detected and corrected. Logical errors are then exponentially suppressed as the number of physical qubits grows, provided that the physical error rates are below a certain threshold. QEC also requires that the errors are local and that performance is maintained over many rounds of error correction, two major outstanding experimental challenges. Here, we implement 1D repetition codes embedded in a 2D grid of superconducting qubits which demonstrate exponential suppression of bit or phase-flip errors, reducing logical error per round by more than \\(100\\) when increasing the number of qubits from 5 to 21. Crucially, this error suppression is stable over 50 rounds of error correction. We also introduce a method for analyzing error correlations with high precision, and characterize the locality of errors in a device performing QEC for the first time. Finally, we perform error detection using a small 2D surface code logical qubit on the same device, and show that the results from both 1D and 2D codes agree with numerical simulations using a simple depolarizing error model. These findings demonstrate that superconducting qubits are on a viable path towards fault tolerant quantum computing.

Interaction in quantum systems can spread initially localized quantum information into the many degrees of freedom of the entire system. Understanding this process, known as quantum scrambling, is the key to resolving various conundrums in physics. Here, by measuring the time-dependent evolution and fluctuation of out-of-time-order correlators, we experimentally investigate the dynamics of quantum scrambling on a 53-qubit quantum processor. We engineer quantum circuits that distinguish the two mechanisms associated with quantum scrambling, operator spreading and operator entanglement, and experimentally observe their respective signatures. We show that while operator spreading is captured by an efficient classical model, operator entanglement requires exponentially scaled computational resources to simulate. These results open the path to studying complex and practically relevant physical observables with near-term quantum processors.

Resistance training may differentially affect morphological adaptations along the length of uni-articular and bi-articular muscles. The purpose of this study was to compare changes in muscle morphology along the length of the rectus femoris (RF) and vastus lateralis (VL) in response to resistance training. Following a 2-wk preparatory phase, 15 resistance-trained men (24.0 ± 3.0 y, 90.0 ± 13.8 kg, 174.9 ± 20.7 cm) completed pre-training (PRE) assessments of muscle thickness (MT), pennation angle (PA), cross-sectional area (CSA), and echo-intensity in the RF and VL at 30, 50, and 70% of each muscle's length; fascicle length (FL) was estimated from respective measurements of MT and PA within each muscle and region. Participants then began a high intensity, low volume (4 x 3-5 repetitions, 3min rest) lower-body resistance training program, and repeated all PRE-assessments after 8 weeks (2 d ∙ wk-1) of training (POST). Although three-way (muscle [RF, VL] x region [30, 50, 70%] x time [PRE, POST]) repeated measures analysis of variance did not reveal significant interactions for any assessment of morphology, significant simple (muscle x time) effects were observed for CSA (p = 0.002) and FL (p = 0.016). Specifically, average CSA changes favored the VL (2.96 ± 0.69 cm2, p < 0.001) over the RF (0.59 ± 0.20 cm2, p = 0.011), while significant decreases in average FL were noted for the RF (-1.03 ± 0.30 cm, p = 0.004) but not the VL (-0.05 ± 0.36 cm, p = 0.901). No other significant differences were observed. The findings of this study demonstrate the occurrence of non-homogenous adaptations in RF and VL muscle size and architecture following 8 weeks of high-intensity resistance training in resistance-trained men. However, training does not appear to influence region-specific adaptations in either muscle.

BackgroundHepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality. The combination of tremelimumab and durvalumab is now a standard treatment option for advanced HCC.ObjectiveTo study immune responses in HCC patients treated with tremelimumab and durvalumab.DesignWe treated 28 HCC patients with durvalumab, tremelimumab and locoregional therapies. We performed a high-dimensional multiomics analysis including whole exome sequencing, single-cell RNA seq, CO-Detection by indEXing, flow cytometry and multiplex cytokine/chemokine analysis of patients’ blood and tumour samples and integrated this data to elucidate immune correlatives and response mechanisms. Mice with syngeneic HCC were treated with anti-PD-L1 plus anti-CTLA4 for hepatic lymphocytes, tumour-infiltrating lymphocytes and peripheral blood mononuclear cell analysis.ResultsThe median overall survival was 19.2 months. Tumour tissue analysis revealed enhanced interferon responses, with stronger effects in responders. Gene set variation analysis indicated enhanced antigen presentation in responders. Spatial analysis revealed that non-responder tumours had higher numbers of Tregs located in neighbourhoods enriched with immune cells and expressed higher levels of ICOS and PD-1. Conversely, non-responder PD1+CD8+T in these Treg-enriched neighbourhoods expressed lower ICOS. Cell-communication analysis demonstrated that Treg-CD8+T interaction was enhanced in non-responder tissue. Peripheral blood analysis showed increased classical monocytes in responders and Tregs in non-responders. Treg-CD8+T interaction was confirmed in preclinical models. Finally, single-patient computational analysis from the all-across analysis was performed on 860 features, which led to the identification of multiomics feature sets including Treg features.ConclusionOur study provides a blueprint for in-depth analysis of immune correlates in immunotherapy studies and demonstrates the importance of Treg distribution in HCC.Trial registration numbers NCT02821754 and the EudraCT identifier: 2019-002767-98.

Phenotypes have been proposed as a method of characterizing subgroups based on biopsychosocial factors to identify responders to analgesic treatments. This study aimed to, first, confirm phenotypes in patients with low back pain receiving physical therapy based on an a priori set of factors used to derive subgroups in other pain populations. Second, an exploratory analysis examined if phenotypes differentiated pain and disability outcomes at four weeks of physical therapy. Fifty-five participants completed psychological questionnaires and pressure pain threshold (PPT). Somatization, anxiety, and depression domains of the Symptom-Checklist-90-Revised, and PPT, were entered into a hierarchical agglomerative cluster analysis with Ward’s method to identify phenotypes. Repeated measures ANOVAs assessed pain ratings and disability by phenotype at four weeks. Three clusters emerged: 1) high emotional distress and pain sensitivity (n = 10), 2) low emotional distress (n = 34), 3) low pain sensitivity (n = 11). As an exploratory study, clusters did not differentiate pain ratings or disability after four weeks of physical therapy (p’s>0.05). However, trends were observed as magnitude of change for pain varied by phenotype. This supports the characterization of homogenous subgroups based on a protocol conducted in the clinical setting with varying effect sizes noted by phenotype for short-term changes in pain. As an exploratory study, future studies should aim to repeat this trial in a larger sample of patients.

BackgroundEmerging clinical and mouse tumor data indicate that tumor cells induce immune suppression in an anatomical site-specific manner. In lung metastases, tumor cell programmed death-ligand 1 (PD-L1) engages myeloid cell programmed cell death protein 1 to activate SHP2 to suppress type I interferon (IFN-I) expression to repress Cxcl9 expression to impair cytotoxic T lymphocyte (CTL) tumor recruitment. Loss of IFN-I expression thus underlies tumor immune evasion in lung metastases niche. We aimed at testing the hypothesis that forcing tumor cells to express IFNα2 activates Cxcl9 expression to increase CTL tumor recruitment to suppress lung metastasis.MethodsCodon usage-optimized IFNα2-encoding DNA was designed and cloned to plasmid. IFNα2-encoding messenger RNA (mRNA) was synthesized. The plasmid DNA and mRNA were encapsulated into DOTAP (N-[1-(2,3-Dioleoyloxy)propyl]-N,N,N-trimethylammonium methyl-sulfate)-cholesterol to generate lipid nanoparticle (LNP)-encapsulated mouse IFNα2 (LNP-mIFNα2), human IFNα2 plasmid, and mouse IFNα2 mRNA (LNP-mIFNα2-mRNA). Mouse breast tumor spontaneous lung metastasis, mouse melanoma experimental lung metastasis, and human colon tumor experimental lung metastasis humanized mouse models were used to determine LNP-encapsulated IFNα2-encoding plasmid and mRNA efficacy in IFNα2 expression and antitumor immunity, toxicity, and mechanism of action in vivo.ResultsLNP-encapsulated IFNα2-encoding plasmid primarily accumulated in tumor-bearing lungs in mice. LNP-IFNα2 therapy produces mouse IFNα2 protein in mouse tumor-bearing mice and human IFNα2 protein in human tumor-bearing humanized mice to suppress lung metastasis, respectively. Similarly, LNP-mIFNα2-mRNA therapy produces mouse IFNα2 protein and suppressed lung metastasis in tumor-bearing mice. The increased IFNα2 protein activates Cxcl9 expression and increases T cell infiltration in lung metastases. LNP-IFNα2 therapy did not induce liver toxicity and inflammatory cytokines. In human patients with cancer, IFN-I pathway activation is correlated with CXCL9 expression and T cell expansion after PD-(L)1 immune checkpoint inhibitor immunotherapy. Mechanistically, LNP-delivered IFNα2 suppresses tumor lung metastasis through upregulating Cxcl9 in tumor-bearing mice.ConclusionsOur findings determine that LNP-encapsulated IFNα2-encoding plasmid DNA and mRNA are effective agents in restoring IFNα2 expression to activate Cxcl9 expression to enhance T cell tumor recruitment to suppress tumor lung metastasis. LNP-IFNα2 is potentially a safe and yet effective third-generation IFNα2 agent for human cancer immunotherapy to treat patients with lung metastasis.

Two men returned to Ohio from the Philippines, where they were unknowingly infected with measles. A measles outbreak subsequently developed in their Amish community. The importance of high vaccination coverage to measles control is highlighted. Measles is a highly contagious, albeit vaccine-preventable, disease that can lead to serious complications. Although endemic transmission of measles in the United States was declared to be eliminated in 2000, 1 importations from countries in which measles is still endemic continue to occur. Despite repeated challenges from measles introductions, most importations of measles do not lead to further spread, and outbreaks are generally small and short-lived. 2 – 4 The success of the measles-control program in the United States is the result of a high rate of coverage with a safe and efficacious vaccine (the measles–mumps–rubella [MMR] vaccine), combined with the aggressive implementation . . .