Entangling power and operator entanglement in qudit systems

We establish the entangling power of a unitary operator on a general finite-dimensional bipartite quantum system with and without ancillas, and give relations between the entangling power based on the von Neumann entropy and the entangling power based on the linear entropy. Significantly, we demonstrate that the entangling power of a general controlled unitary operator acting on two equal-dimensional qudits is proportional to the corresponding operator entanglement if linear entropy is adopted as the quantity representing the degree of entanglement. We discuss the entangling power and operator entanglement of three representative quantum gates on qudits: the SUM, double SUM, and SWAP gates.Comment: 8 pages, 1 figure. Version 3: Figure was improved and the MS was a bit shortene

Entanglement capability of self-inverse Hamiltonian evolution

We determine the entanglement capability of self-inverse Hamiltonian evolution, which reduces to the known result for Ising Hamiltonian, and identify optimal input states for yielding the maximal entanglement rate. We introduce the concept of the operator entanglement rate, and find that the maximal operator entanglement rate gives a lower bound on the entanglement capability of a general Hamiltonian.Comment: 4 pages, no figures. Version 3: small change

The Carnegie-Chicago Hubble Program. VIII. An Independent Determination of the Hubble Constant Based on the Tip of the Red Giant Branch

We present a new and independent determination of the local value of the Hubble constant based on a calibration of the tip of the red giant branch (TRGB) applied to Type Ia supernovae (SNe Ia). We find a value of H0 = 69.8 ± 0.8 (±1.1% stat) ± 1.7 (±2.4% sys) km s−1 Mpc−1. The TRGB method is both precise and accurate and is parallel to but independent of the Cepheid distance scale. Our value sits midway in the range defined by the current Hubble tension. It agrees at the 1.2σ level with that of the Planck Collaboration et al. estimate and at the 1.7σ level with the Hubble Space Telescope (HST) SHoES measurement of H0 based on the Cepheid distance scale. The TRGB distances have been measured using deep HST Advanced Camera for Surveys imaging of galaxy halos. The zero-point of the TRGB calibration is set with a distance modulus to the Large Magellanic Cloud of 18.477 ± 0.004 (stat) ± 0.020 (sys) mag, based on measurement of 20 late-type detached eclipsing binary stars, combined with an HST parallax calibration of a 3.6 μm Cepheid Leavitt law based on Spitzer observations. We anchor the TRGB distances to galaxies that extend our measurement into the Hubble flow using the recently completed Carnegie Supernova Project I ( CSP-I ) sample containing about 100 well-observed SNe Ia . There are several advantages of halo TRGB distance measurements relative to Cepheid variables; these include low halo reddening, minimal effects of crowding or blending of the photometry, only a shallow (calibrated) sensitivity to metallicity in the I band, and no need for multiple epochs of observations or concerns of different slopes with period. In addition, the host masses of our TRGB host-galaxy sample are higher, on average, than those of the Cepheid sample, better matching the range of host-galaxy masses in the CSP-I distant sample and reducing potential systematic effects in the SNe Ia measurements

The EORTC-DeCOG nomogram adequately predicts outcomes of patients with sentinel node–positive melanoma without the need for completion lymph node dissection

Purpose: Based on recent advances in the management of patients with sentinel node (SN)–positive melanoma, we aimed to develop prediction models for recurrence, distant metastasis (DM) and overall mortality (OM). Methods: The derivation cohort consisted of 1080 patients with SN-positive melanoma from nine European Organization for Research and Treatment of Cancer (EORTC) centres. Prognostic factors for recurrence, DM and OM were studied with Cox regression analysis. Significant factors were incorporated in the models. Performance was assessed by discrimination (c-index) and calibration in cross-validation across centres. The models were externally validated using a prospective cohort consisting of 705 German patients with SN-positive: 473 trial participants of the German Dermatologic Cooperative Oncology Group study (DeCOG-SLT) and 232 screened patients. A nomogram was developed for graphical presentation. Results: The final model for recurrence and the calibrated models for DM and OM included ulceration, age, SN tumour burden and Breslow thickness. The models showed reasonable calibration. The c-index for the recurrence, DM and OM model was 0.68, 0.70 and 0.70, respectively, and 0.70, 0.72 and 0.74, respectively, in external validation. The EORTC-DeCOG model identified a robust low-risk group, with all identified low-risk patients (approximately 4% of the entire population) having a 5-year recurrence probability of <25% and an overall 5-year recurrence rate of 13%. A model including information on completion lymph node dissection (CLND) showed only marginal improvement in model performance. Conclusions: The EORTC-DeCOG nomogram provides an adequate prognostic tool for patients with SN-positive melanoma, without the need for CLND. It showed consistent results across validation. The nomogram could be used for patient counselling and might aid in adjuvant therapy decision-making

Global analysis of community-associated methicillin-resistant Staphylococcus aureus exoproteins reveals molecules produced in vitro and during infection

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is a threat to human health worldwide. Although progress has been made, mechanisms of CA-MRSA pathogenesis are poorly understood and a comprehensive analysis of CA-MRSA exoproteins has not been conducted. To address that deficiency, we used proteomics to identify exoproteins made by MW2 (USA400) and LAC (USA300) during growth in vitro. Two hundred and fifty unique exoproteins were identified by 2-dimensional gel electrophoresis coupled with automated direct infusion-tandem mass spectrometry (ADI-MS/MS) analysis. Eleven known virulence-related exoproteins differed in abundance between the strains, including alpha-haemolysin (Hla), collagen adhesin (Cna), staphylokinase (Sak), coagulase (Coa), lipase (Lip), enterotoxin C3 (Sec3), enterotoxin Q (Seq), V8 protease (SspA) and cysteine protease (SspB). Mice infected with MW2 or LAC produced antibodies specific for known or putative virulence factors, such as autolysin (Atl), Cna, Ear, ferritin (Ftn), Lip, 1-phosphatidylinositol phosphodiesterase (Plc), Sak, Sec3 and SspB, indicating the exoproteins are made during infection in vivo. We used confocal microscopy to demonstrate aureolysin (Aur), Hla, SspA and SspB are produced following phagocytosis by human neutrophils, thereby linking exoprotein production in vitro with that during host–pathogen interaction. We conclude that the exoproteins identified herein likely account in part for the success of CA-MRSA as a human pathogen

Structures of DPAGT1 explain glycosylation disease mechanisms and advance TB antibiotic design

Summary: Protein N-glycosylation is a widespread post-translational modification. The first committed step in this process is catalysed by dolichyl-phosphate N-acetylglucosamine-phosphotransferase DPAGT1 (GPT/E.C. 2.7.8.15). Missense DPAGT1 variants cause congenital myasthenic syndrome and disorders of glycosylation. In addition, naturally-occurring bactericidal nucleoside analogues such as tunicamycin are toxic to eukaryotes due to DPAGT1 inhibition, preventing their clinical use. Our structures of DPAGT1 with the substrate UDP-GlcNAc and tunicamycin reveal substrate binding modes, suggest a mechanism of catalysis, provide an understanding of how mutations modulate activity (thus causing disease) and allow design of non-toxic “lipid-altered” tunicamycins. The structure-tuned activity of these analogues against several bacterial targets allowed the design of potent antibiotics for Mycobacterium tuberculosis, enabling treatment in vitro, in cellulo and in vivo, providing a promising new class of antimicrobial drug

SARS-CoV-2 is transmitted via contact and via the air between ferrets

SARS-CoV-2, a coronavirus that emerged in late 2019, has spread rapidly worldwide, and information about the modes of transmission of SARS-CoV-2 among humans is critical to apply appropriate infection control measures and to slow its spread. Here we show that SARS-CoV-2 is transmitted efficiently via direct contact and via the air (via respiratory droplets and/or aerosols) between ferrets, 1 to 3 days and 3 to 7 days after exposure respectively. The pattern of virus shedding in the direct contact and indirect recipient ferrets is similar to that of the inoculated ferrets and infectious virus is isolated from all positive animals, showing that ferrets are productively infected via either route. This study provides experimental evidence of robust transmission of SARS-CoV-2 via the air, supporting the implementation of community-level social distancing measures currently applied in many countries in the world and informing decisions on infection control measures in healthcare settings