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Fast radio bursts (FRBs) are millisecond-duration radio transients 1 , 2 of unknown origin. Two possible mechanisms that could generate extremely coherent emission from FRBs invoke neutron star magnetospheres 3 – 5 or relativistic shocks far from the central energy source 6 – 8 . Detailed polarization observations may help us to understand the emission mechanism. However, the available FRB polarization data have been perplexing, because they show a host of polarimetric properties, including either a constant polarization angle during each burst for some repeaters 9 , 10 or variable polarization angles in some other apparently one-off events 11 , 12 . Here we report observations of 15 bursts from FRB 180301 and find various polarization angle swings in seven of them. The diversity of the polarization angle features of these bursts is consistent with a magnetospheric origin of the radio emission, and disfavours the radiation models invoking relativistic shocks. Polarization observations of the fast radio burst FRB 180301 with the FAST radio telescope show diverse polarization angle swings, consistent with a magnetospheric origin of the emission.

The dynamics of a nuclear open quantum system could be revealed in the correlations between the breakup fragments of halo nuclei. The breakup mechanism of a proton halo nuclear system is of particular interest as the Coulomb polarization may play an important role, which, however, remains an open question. Here we use a highly efficient silicon detector array and measure the correlations between the breakup fragments of 8 B incident on 120 Sn at near-barrier energies. The energy and angular correlations can be explained by a fully quantum mechanical method based on the state-of-the-art continuum discretized coupled channel calculations. The results indicate that, compared to the neutron halo nucleus 6 He, 8 B presents distinctive reaction dynamics: the dominance of the elastic breakup. This breakup occurs mainly via the short-lived continuum states, almost exhausts the 7 Be yield, indicating the effect of Coulomb polarization on the proton halo state. The correlation information reveals that the prompt breakup mechanism dominates, occurring predominantly on the outgoing trajectory. We also show that, as a large environment, the continuum of 8 B breakup may not significantly influence elastic scattering and complete fusion. Halo-structured nuclei are examples of many-body open quantum system. Here the authors use a complete kinematics measurement and find an elastic breakup of proton halo nucleus 8 B.

VEGF inhibitors can enhance the efficacy of immunotherapy. However, despite high initial response rates, almost all patients eventually develop treatment resistance to EGFR tyrosine-kinase inhibitors. We aimed to evaluate the efficacy and safety of sintilimab with or without IBI305 plus pemetrexed and cisplatin, compared with pemetrexed and cisplatin alone, for the treatment of patients with locally advanced or metastatic EGFR-mutated non-small-cell lung cancer (NSCLC) who had disease progression after receiving EGFR tyrosine-kinase inhibitor therapy. This randomised, double-blind, multicentre, phase 3 trial was conducted at 52 hospitals in China. Eligible participants were adults aged 18–75 years with locally advanced or metastatic NSCLC and EGFRmut who progressed after receiving a EGFR tyrosine-kinase inhibitor, had an Eastern Cooperative Oncology Group performance status of 0 or 1 with at least one measurable lesion, and an estimated life expectancy of at least 3 months. Participants were randomly assigned (1:1:1) to receive sintilimab (200 mg) plus IBI305 (15 mg/kg) plus pemetrexed (500 mg/m2) and cisplatin (75 mg/m2), sintilimab plus pemetrexed and cisplatin, or pemetrexed and cisplatin (chemotherapy alone) using block randomisation with stratification according to sex and presence or absence of brain metastases. All study drugs were administered intravenously on day 1 of each cycle, once every 3 weeks. Except for cisplatin, which was only given in the first four cycles, treatment was given for 24 months or until disease progression, intolerable toxic effects, withdrawal of consent, death, or other protocol-specified conditions, whichever occurred first. The primary endpoint was progression-free survival in the intention-to-treat population. We herein report the first planned interim analysis, with progression-free survival results for the comparison between sintilimab plus IBI305 plus chemotherapy versus chemotherapy alone. The progression-free survival results for the sintilimab plus pemetrexed and cisplatin group are immature and not reported here. This study is registered with ClinicalTrials.gov, NCT03802240 (recruiting). Between July 11, 2019, and July 31, 2021, 936 patients were screened and 444 were randomly assigned (148 to the sintilimab plus IBI305 plus chemotherapy group, 145 to the sintilimab plus chemotherapy group, and 151 to the chemotherapy alone group). Data cutoff for this interim analysis was July 31, 2021. After a median follow-up of 9·8 months (IQR 4·4–13·3), progression-free survival was significantly longer in the sintilimab plus IBI305 plus chemotherapy group versus the chemotherapy alone group (median 6·9 months [95% CI 6·0–9.3] vs 4·3 months [4·1–5·4]; hazard ratio 0·46 [0·34–0·64]; p<0·0001). The most common grade 3 or 4 treatment-related adverse events were decreased neutrophil count (30 [20%] in the sintilimab plus IBI305 plus chemotherapy group vs 26 [18%] in the sintilimab plus chemotherapy group vs 27 [18%] in the chemotherapy alone group), decreased white blood cell count (17 [11%] vs 12 [8%] vs 13 [9%]), and anaemia (18 [12%] vs ten [7%] vs 15 [10%]). Potentially treatment-related deaths occurred in six patients (intestinal obstruction, gastrointestinal haemorrhage, and myelosuppression in one patient each, and three deaths of unknown cause) in the sintilimab plus IBI305 plus chemotherapy group, and in one patient in the chemotherapy alone group (unknown cause). In this interim analysis, sintilimab plus IBI305 plus cisplatin and pemetrexed was generally efficacious and well tolerated in patients with EGFR-mutated NSCLC who progressed after receiving EGFR tyrosine-kinase inhibitor therapy. Innovent Biologics and the National Natural Science Foundation of China. For the Chinese translation of the abstract see Supplementary Materials section.

During the last few decades, the most widely favored models for coronal heating have involved the in situ dissipation of energy, with footpoint shuffling giving rise to multiple current sheets (the nanoflare model) or to Alfvén waves that leak into the corona and undergo dissipative interactions (the wave heating scenario). As has been recognized earlier, observations suggest instead that the energy deposition is concentrated at low heights, with the coronal loops being filled with hot, dense material from below, which accounts for their overdensities and flat temperature profiles. While an obvious mechanism for footpoint heating would be reconnection with small-scale fields, this possibility seems to have been widely ignored because magnetograms show almost no minority-polarity flux inside active-region (AR) plages. Here, we present further examples to support our earlier conclusions (1) that magnetograms greatly underrepresent the amount of minority-polarity flux inside plages and “unipolar” network, and (2) that small loops are a major constituent of Fe ix 17.1-nm moss. On the assumption that the emergence or churning rate of small-scale flux is the same inside plages as in mixed-polarity regions of the quiet Sun, we estimate the energy flux density associated with reconnection with the plage fields to be on the order of 10 7 erg cm − 2 s − 1 , sufficient to heat the AR corona.