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Background and study aims: The long-term comprehensive prognosis of chronic hepatitis C after direct-acting antiviral (DAA) therapy is unclear. This study aimed to investigate the prognosis and incidence of immunological and oncological complications after DAA therapy. Patients and methods: The study included a total of 1461 patients who received DAA therapy in our university hospital and affiliated hospitals between September 3, 2014 and September 30, 2018. Results: The incidence rates of total malignancies in overall or female patients after DAA therapy were significantly greater than expected in the corresponding general population. The same was true for lung malignancies. Predictive risk factors associated with the occurrence and recurrence of hepatic malignancies after DAA therapy in patients with sustained virological response were cirrhosis and insulin use, protein induced by vitamin K absence or antagonist-II level, and albumin-bilirubin score, respectively. Eight (0.5%) patients were diagnosed with autoimmune diseases after starting DAA therapy. Importantly, the attending physician considered a possible causal relationship between DAA therapy and these autoimmune diseases in five cases (four rheumatoid arthritis and one membranoproliferative glomerulonephritis). The 5-year overall survival rate was 91.6%. The most frequent primary cause of death was malignancy in 41 (60.2%) patients, including 25 with hepatic malignancies. Lung and colorectal cancers were the next most common. Conclusions: Given that the incidence of total and lung cancers might increase and DAA-related autoimmune diseases might emerge after DAA therapy, we should be alert for the development of these diseases as well as hepatic malignancies.

A key feature of quantum spin liquids is the predicted formation of fractionalized excitations. They are expected to produce changes in the physical response, providing a way to observe the quantum spin liquid state1. In the honeycomb magnet α-RuCl3, a quantum spin liquid has been proposed to explain the behaviour observed on applying an in-plane magnetic field H||. Previous work reported that the thermal Hall conductivity took on a half-integer quantized value and suggested this as a signature of a fractionalized Majorana edge mode predicted to exist in Kitaev quantum spin liquids2. However, the temperature and magnetic-field range of the half-quantized signal2–4 and its association with Majorana edge modes are still under debate5,6. Here we present a comprehensive study of the thermal Hall conductivity in α-RuCl3 showing that approximately half-integer quantization exists in an extended region of the phase diagram, particularly across a plateau-like parameter regime for H|| exceeding 10 T and temperature below 6.5 K. At lower fields, the thermal Hall conductivity exhibits correlations with complex anomalies in the longitudinal thermal conductivity and magnetization, and is suppressed by cooling to low temperatures. Our results can be explained by the existence of a topological state in magnetic fields above 10 T.

In ferromagnets, electric current generally induces transverse Hall voltage in proportion to magnetization (anomalous Hall effect), and it is frequently used for electrical readout of the up and down spin states. While these properties are usually not expected in antiferromagnets, recent theoretical studies predicted that non-coplanar antiferromagnetic order with finite scalar spin chirality (i.e. solid angle spanned by neighboring spins) can often induce large spontaneous Hall effect even without net magnetization or external magnetic field. This phenomenon, i.e. spontaneous topological Hall effect, can potentially be used for the efficient electrical readout of the antiferromagnetic states, but its experimental verification has long been elusive due to the lack of appropriate materials hosting such exotic magnetism. Here, we report the discovery of all-in-all-out type non-coplanar antiferromagnetic order in triangular lattice compounds CoTa3S6 and CoNb3S6, by performing the detailed magnetic structure analysis based on polarized neutron scattering experiments as well as systematic first-principles calculations. These compounds are reported to host unconventionally large spontaneous Hall effect despite their vanishingly small net magnetization, and our analysis revealed that it can be well explained in terms of topological Hall effect, which originates from the fictitious magnetic field associated with scalar spin chirality in non-coplanar antiferromagnetic orders. The present results indicate that the scalar spin chirality mechanism can offer a promising route to realize giant spontaneous Hall response even in compensated antiferromagnets, and highlight intercalated van der Waals magnets as an unique quasi-two-dimensional material platform to enable various nontrivial manner of electrical reading and possible writing of non-coplanar antiferromagnetic domains., Comment: to appear in Nature Physics

Funding: A. W. R. and A. S. G. were supported by the Engineering and Physical Sciences Research Council (grant numbers EP/P024564/1 and EP/T011130/1 respectively). This work has been supported in part by the Alexander von Humboldt Foundation. The band topology of magnetic semimetals is of interest both from the fundamental science point of view and with respect to potential spintronics and memory applications. Unfortunately, only a handful of suitable topological semimetals with magnetic order have been discovered so far. One such family that hosts these characteristics is the antiperovskites, A3BO, a family of 3D Dirac semimetals. The A=Eu2+ compounds magnetically order with multiple phases as a function of applied magnetic field. Here, by combining band structure calculations with neutron diffraction and magnetic measurements, we establish the antiperovskite Eu3PbO as a new topological magnetic semimetal. This topological material exhibits a multitude of different topological phases with ordered Eu moments which can be easily controlled by an external magnetic field. The topological phase diagram of Eu3PbO includes an antiferromagnetic Dirac phase, as well as ferro- and ferrimagnetic phases with both Weyl points and nodal lines. For each of these phases, we determine the bulk band dispersions, the surface states, and the topological invariants by means of ab initio and tight-binding calculations. Our discovery of these topological phases introduces Eu3PbO as a new platform to study and manipulate the interplay of band topology, magnetism, and transport. Publisher PDF

The inverse perovskite Sr3SnO is a 3D cubic Dirac semimetal with a very small energy gap[1]. Its unusual electronic structure confers a variety of novel properties, such as chiral topological surface states, and very strong itinerant electron orbital magnetism. Remarkably, when doped it also becomes superconducting[2]. In the lowest carrier density samples, the Fermi level lies close to the Dirac points, and orbital magnetism is maximal. Here we report the results of ion-implanted 8Li+ βNMR in Au-capped epitaxial thin films of Sr3SnO as a function of carrier content. In addition, we stop the 8Li in the Au overlayer to seek proximal evidence of the chiral surface state. In high magnetic field (6.55 T), we find remarkably little contrast in spin-lattice relaxation (SLR) between low carrier density Sr3SnO and the Au overlayer. In the inverse perovskite layer, 1/T 1 ∼ 0.14 s-1, slightly faster than Au at 300 K, while in the overlayer, there is a small but systematic enhancement in 1/T 1 compared to a control film of Au. The resonance in the Sr3SnO layer is broad with a long tail towards negative shift without resolved quadrupolar splitting.

In various so-called strange metals, electrons undergo Planckian dissipation1,2, a strong and anomalous scattering that grows linearly with temperature3, in contrast to the quadratic temperature dependence expected from the standard theory of metals. In some cuprates4,5 and pnictides6, a linear dependence of resistivity on a magnetic field has also been considered anomalous—possibly an additional facet of Planckian dissipation. Here we show that the resistivity of the cuprate strange metals Nd0.4La1.6−xSrxCuO4 (ref. 7) and La2−xSrxCuO4 (ref. 8) is quantitatively consistent with the standard Boltzmann theory of electron motion in a magnetic field, in all aspects—field strength, field direction, temperature and disorder level. The linear field dependence is found to be simply the consequence of scattering rate anisotropy. We conclude that Planckian dissipation is anomalous in its temperature dependence, but not in its field dependence. The scattering rate in these cuprates does not depend on field, which means that their Planckian dissipation is robust against fields up to at least 85 T.

The nature of the pseudogap phase of cuprates remains a major puzzle1,2. One of its signatures is a large negative thermal Hall conductivity3, whose origin is as yet unknown. This is observed even in the undoped Mott insulator La2CuO4, in which the charge carriers are localized and therefore cannot be responsible. Here, we show that the thermal Hall conductivity of La2CuO4 is roughly isotropic; that is, for heat transport parallel and normal to the CuO2 planes, it is nearly the same. This shows that the Hall response must come from phonons, as they are the only heat carriers that are able to move with the same ease both normal and parallel to the planes4. For doping levels higher than the critical doping level at which the pseudogap phase ends, both La1.6−xNd0.4SrxCuO4 and La1.8−xEu0.2SrxCuO4 show no thermal Hall signal for a heat current normal to the planes, which establishes that phonons have zero Hall response outside the pseudogap phase. Inside the pseudogap phase, the phonons must become chiral to generate the Hall response, but the mechanism by which this happens remains to be identified. It must be intrinsic (from a coupling of phonons to their electronic environment) rather than extrinsic (from structural defects or impurities), as these are the same on both sides of critical doping. Thermal transport measurements show that there is a thermal Hall effect in the out-of-plane direction in two cuprates in the pseudogap regime. This indicates that phonons are carrying the heat and that they have a handedness of unknown origin.

Background Durability of different transcatheter heart valve (THV) is critical as the indication of transcatheter aortic valve replacement (TAVR) expands to patients with longer life-expectancy. Purpose We aimed to compare the durability of THV systems (balloon-expandable [BE] and self-expandable [SE]) and surgical aortic valve replacement (SAVR) prosthesis. Methods PUBMED and EMBASE were searched through February 2021 for randomized trials investigating parameters of valve durability after TAVR and/or SAVR in severe aortic stenosis. A network meta-analysis using random-effect model was performed. Synthesis was performed with 5-year follow-up data for echocardiographic outcomes and longest available follow-up data for clinical outcomes. Results Ten trials with a total of 9,388 patients (BE-THV: 2,562; SE-THV 2,863; SAVR:3,963) were included. Follow-up ranged from 1–6 years. SE-THV demonstrated significantly larger effective orifice area, lower mean aortic valve gradient (AVG), and less increase in mean AVG at 5-years compared to BE-THV and SAVR (Figure 1). Structural valve deterioration (SVD) was less frequent in SE-THV compared to BE-THV and SAVR (HR 0.14, 95% CI 0.07–0.27; HR 0.34, 95% CI 0.24–0.47, respectively) (Figure 1). Total moderate-severe aortic regurgitation and re-intervention was more frequent in BE-THV (HR 4.21, 95% CI 2.40–7.39; HR 2.22, 95% CI 1.16–4.26, respectively) and SE-THV (HR 7.51, 95% CI 3.89–14.5; HR 2.86, 95% CI 1.59–5.13, respectively) compared to SAVR. Conclusion TAVR with SE-THV demonstrated favorable forward-flow hemodynamics and lowest risk of SVD compared to BE-THV and SAVR at mid-term. However, both THV systems suffer an increased risk of aortic regurgitation and re-intervention, and long-term data from newer generation valve is warranted. Funding Acknowledgement Type of funding sources: None.

Background Based on a recent randomized control trial (RCT), prasugrel is recommended in preference to ticagrelor for patients with non-ST-segment elevation ACS (NSTE-ACS), however, limited data exists. Objectives We aimed to investigate the effect of P2Y12 inhibitors on ischemic and bleeding events in NSTE-ACS patients. Methods Clinical trials enrolling NSTE-ACS patients were identified and relevant data was extracted. We performed a network meta-analysis on efficacy and safety outcomes. Results Our study including a total of 37, 268 patients with NSTE-ACS from 11 RCTs. Prasugrel decreased major adverse cardiovascular events (MACE) when compared to clopidogrel (Hazard ratio (HR): 0.84; 95% confidence interval (CI) [0.71–0.99]). For MACE, prasugrel showed the highest likelihood of event reduction (P-score=0.97) in comparison to ticagrelor (P-score=0.29) and clopidogrel (P-score=0.24). Prasugrel decreased myocardial infarction (HR: 0.82; 95% CI [0.68–0.99]) but increased major bleeding without statistical significance (HR: 1.30; 95% CI [0.97–1.74]) when compared to clopidogrel. Ticagrelor reduced cardiovascular death (HR: 0.79; 95% CI [0.66–0.94]) but increased major bleeding (HR: 1.33; 95% CI [1.00–1.77], p=0.049) in comparison to clopidogrel. There was no significant difference between prasugrel and ticagrelor for each endpoint, but prasugrel had higher likelihood of event reduction than ticagrelor for all endpoints except cardiovascular death. Conclusions Prasugrel and ticagrelor had comparable risk for each endpoint, but prasugrel had the highest probability being the best treatment in reducing the primary endpoint. This study highlights the need for further large-scale RCTs to investigate the optimal P2Y12 inhibitor selection in NSTE-ACS patients. Funding Acknowledgement Type of funding sources: None.

The specific heat $C$ of the cuprate superconductors ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{CuO}}_{4}$ and ${\mathrm{Bi}}_{2+y}{\mathrm{Sr}}_{2\ensuremath{-}x\ensuremath{-}y}{\mathrm{La}}_{x}{\mathrm{CuO}}_{6+\ensuremath{\delta}}$ was measured at low temperatures (down to 0.5 K) for dopings $p$ close to ${p}^{★}$, the critical doping for the onset of the pseudogap phase. A magnetic field up to 35 T was applied to suppress superconductivity, giving direct access to the normal state at low temperatures, and enabling a determination of ${C}_{\mathrm{e}}$, the electronic contribution to the normal-state specific heat at $T\ensuremath{\rightarrow}0$. In ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{CuO}}_{4}$ at $x=p=0.22$, 0.24 and 0.25, ${C}_{\mathrm{e}}/T=15\phantom{\rule{0.28em}{0ex}}\mathrm{to}\phantom{\rule{0.28em}{0ex}}16\phantom{\rule{0.28em}{0ex}}\mathrm{mJ}\phantom{\rule{0.16em}{0ex}}{\mathrm{mol}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}{\mathrm{K}}^{\ensuremath{-}2}$ at $T=2\phantom{\rule{0.28em}{0ex}}\mathrm{K}$, values that are twice as large as those measured at higher doping ($pg0.3$) and lower doping ($pl0.15$). This confirms the presence of a broad peak in the doping dependence of ${C}_{\mathrm{e}}$ at ${p}^{★}\ensuremath{\simeq}0.19$ as previously reported for samples in which superconductivity was destroyed by Zn impurities. Moreover, at those three dopings, we find a logarithmic growth as $T\ensuremath{\rightarrow}0$ such that ${C}_{\mathrm{e}}/T\ensuremath{\sim}B\phantom{\rule{0.16em}{0ex}}ln({T}_{0}/T)$. The peak versus $p$ and the logarithmic dependence versus $T$ are the two typical thermodynamic signatures of quantum criticality. In the very different cuprate ${\mathrm{Bi}}_{2+y}{\mathrm{Sr}}_{2\ensuremath{-}x\ensuremath{-}y}{\mathrm{La}}_{x}{\mathrm{CuO}}_{6+\ensuremath{\delta}}$, we again find that ${C}_{\mathrm{e}}/T\ensuremath{\sim}B\phantom{\rule{0.16em}{0ex}}ln({T}_{0}/T)$ at $p\ensuremath{\simeq}{p}^{★}$, strong evidence that this $ln(1/T)$ dependence of the electronic specific heat---first discovered in the cuprates ${\mathrm{La}}_{1.8\ensuremath{-}x}{\mathrm{Eu}}_{0.2}{\mathrm{Sr}}_{x}{\mathrm{CuO}}_{4}$ and ${\mathrm{La}}_{1.6\ensuremath{-}x}{\mathrm{Nd}}_{0.4}{\mathrm{Sr}}_{x}{\mathrm{CuO}}_{4}$---is a universal property of the pseudogap critical point.

We have carried out $\nu_{\mu}$ charged-current interaction measurement on iron using an emulsion detector exposed to the T2K neutrino beam in the J-PARC neutrino facility. The data samples correspond to 4.0$\times$10$^{19}$ protons on target, and the neutrino mean energy is 1.49$\,$GeV. The emulsion detector is suitable for precision measurements of charged particles produced in neutrino-iron interactions with a low momentum threshold thanks to thin-layered structure and sub-$\mu$m spatial resolution. The charged particles are successfully detected, and their multiplicities are measured using the emulsion detector. The cross section was measured to be $\sigma^{\mathrm{Fe}}_{\mathrm{CC}} = (1.28 \pm 0.11({\mathrm{stat.}})^{+0.12}_{-0.11}({\mathrm{syst.}})) \times 10^{-38} \, {\mathrm{cm}}^{2}/{\mathrm{nucleon}}$. The cross section in a limited kinematic phase space of induced muons, $\theta_{\mu} < 45^{\circ}$ and $p_{\mu} > 400 \, {\rm MeV}/c$, on iron was $\sigma^{\mathrm{Fe}}_{\mathrm{CC \hspace{1mm} phase \hspace{0.5mm} space}} = (0.84 \pm 0.07({\mathrm{stat.}})^{+0.07}_{-0.06}({\mathrm{syst.}})) \times 10^{-38} \, {\mathrm{cm}}^{2}/{\mathrm{nucleon}}$. The cross-section results are consistent with previous values obtained via different techniques using the same beamline, and they are well reproduced by current neutrino interaction models. These results demonstrate the capability of the detector towards the detailed measurements of the neutrino-nucleus interactions around the 1$\,$GeV energy region., Comment: 27 pages, 17 figures

Photo-induced phase transitions have been intensively studied owing to the ability to control a material of interest in the ultrafast manner, which can induce exotic phases unable to be attained at equilibrium. However, the key mechanisms are still under debate, and it has currently been a central issue how the couplings between the electron, lattice, and spin degrees of freedom are evolving during photo-induced phase transitions. Here, we develop a new analysis method, frequency-domain angle-resolved photoemission spectroscopy, to gain precise insight into electron-phonon couplings during photo-induced insulator-to-metal transitions for Ta$_2$NiSe$_5$. We demonstrate that multiple coherent phonons generated by displacive excitations show band-selective coupling to the electrons. Furthermore, we find that the lattice modulation corresponding to the 2 THz phonon mode, where Ta lattice is sheared along the a-axis, is the most relevant for the photo-induced semimetallic state.

This work was supported by Japan Society for the Promotion of Science (JSPS) KAKENHI (Grants No. 24224010, No. 15K13523, No. JP15H05852, No. JP15K21717,, No. 17H01140, No. 18H01162, and No. 17J05243), JSPS Core-to-Core Program (A) Advanced Research Networks, and the Alexander von Humboldt Foundation. S.S. acknowledges financial support by JSPS and the Materials Education program for the future leaders in Research, Industry, and Technology (MERIT). In Dirac semimetals, interband mixing has been known theoretically to give rise to a giant orbital diamagnetism when the Fermi level is close to the Dirac point. In Bi1−xSbx and other Dirac semimetals, an enhanced diamagnetism in the magnetic susceptibility χ has been observed and interpreted as a manifestation of such giant orbital diamagnetism. Experimentally proving their orbital origin, however, has remained challenging. The cubic antiperovskite Sr3PbO is a three-dimensional Dirac electron system and shows the giant diamagnetism in χ as in the other Dirac semimetals. 207Pb NMR measurements are conducted in this study to explore the microscopic origin of diamagnetism. From the analysis of the Knight shift K as a function of χ and the relaxation rate T1–1 for samples with different hole densities, the spin and the orbital components in K are successfully separated. The results establish that the enhanced diamagnetism in Sr3PbO originates from the orbital contribution of Dirac electrons, which is fully consistent with the theory of giant orbital diamagnetism. Publisher PDF

The layered delafossite PdCoO2 has been predicted to be one of very few materials with a thermopower that is highly anisotropic and switches sign between different crystallographic directions. These properties are of interest for various applications, but have been difficult to verify because sufficiently large crystals have not been available. We report measurements of the high-temperature electrical resistivity, thermal conductivity, and thermopower of phase-pure PdCoO2 powder compacts prepared by a highly Pd-efficient synthesis route. While the electronic transport of the polycrystalline samples is dominated by that of the Pd planes, the thermopower exhibits a well-defined deviation from the in-plane character at temperatures above 600K, which is indicative of opposing trends in the Seebeck coefficients within and perpendicular to the delafossite layers. The experimental data are consistently described by a combination of effective-medium models based on the main axes transport quantities. The results support the predicted ambipolar thermopower anisotropy in PdCoO2.

This paper reports the track multiplicity and kinematics of muons, charged pions, and protons from charged-current inclusive $\bar{\nu}_{\mu}$ and $\nu_{\mu}$ interactions on a water target, measured using a nuclear emulsion detector in the NINJA experiment. A 3-kg water target was exposed to the T2K antineutrino-enhanced beam with a mean energy of 1.3 GeV. Owing to the high-granularity of the nuclear emulsion, protons with momenta down to 200 MeV/$c$ from the neutrino-water interactions were detected. We find good agreement between the observed data and model predictions for all kinematic distributions other than the number of charged pions. These results demonstrate the capability of measurements with nuclear emulsion to improve neutrino interaction models.

The transition metal chalcogenide ${\mathrm{Ta}}_{2}{\mathrm{NiSe}}_{5}$ undergoes a second-order phase transition at ${T}_{c}=328\phantom{\rule{0.16em}{0ex}}\text{K}$ involving a small lattice distortion. Below ${T}_{c}$, a band gap at the center of its Brillouin zone increases up to about 0.35 eV. In this work, we study the electronic structure of ${\mathrm{Ta}}_{2}{\mathrm{NiSe}}_{5}$ in its low-temperature semiconducting phase, using resonant inelastic x-ray scattering (RIXS) at the Ni ${L}_{3}$ edge. In addition to a weak fluorescence response, we observe a collection of intense Raman-like peaks that we attribute to electron-hole excitations. Using density functional theory calculations of its electronic band structure, we identify the main Raman-like peaks as interband transitions between valence and conduction bands. By performing angle-dependent RIXS measurements, we uncover the dispersion of these electron-hole excitations that allows us to extract the low-energy boundary of the electron-hole continuum. From the dispersion of the valence band measured by angle-resolved photoemission spectroscopy, we derive the effective mass of the lowest unoccupied conduction band.

A hyperkagome iridate ${\mathrm{Li}}_{3}{\mathrm{Ir}}_{3}{\mathrm{O}}_{8}$ is synthesized by an ion-exchange reaction from ${\mathrm{Na}}_{4}{\mathrm{Ir}}_{3}{\mathrm{O}}_{8}$. The transport, magnetic, and thermodynamic measurements suggest a metallic state. The electronic structure calculation shows that ${\mathrm{Li}}_{3}{\mathrm{Ir}}_{3}{\mathrm{O}}_{8}$ hosts a semimetallic electronic structure produced by a competition between the formation of a localized molecular orbital of Ir $d$ electrons on the ${\mathrm{Ir}}_{3}$ triangles and the strong spin-orbit coupling as in the sister compound ${\mathrm{Na}}_{3}{\mathrm{Ir}}_{3}{\mathrm{O}}_{8}$. The semimetallic state induced by spin-orbit coupling is quite robust against the moderate change of lattice distortion associated with the different ionic radii of ${\mathrm{Li}}^{+}$ and ${\mathrm{Na}}^{+}$.