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Fast radio bursts (FRBs) are highly dispersed, millisecond-duration radio bursts 1 – 3 . Recent observations of a Galactic FRB 4 – 8 suggest that at least some FRBs originate from magnetars, but the origin of cosmological FRBs is still not settled. Here we report the detection of 1,863 bursts in 82 h over 54 days from the repeating source FRB 20201124A (ref.  9 ). These observations show irregular short-time variation of the Faraday rotation measure (RM), which scrutinizes the density-weighted line-of-sight magnetic field strength, of individual bursts during the first 36 days, followed by a constant RM. We detected circular polarization in more than half of the burst sample, including one burst reaching a high fractional circular polarization of 75%. Oscillations in fractional linear and circular polarizations, as well as polarization angle as a function of wavelength, were detected. All of these features provide evidence for a complicated, dynamically evolving, magnetized immediate environment within about an astronomical unit ( au ; Earth–Sun distance) of the source. Our optical observations of its Milky-Way-sized, metal-rich host galaxy 10 – 12 show a barred spiral, with the FRB source residing in a low-stellar-density interarm region at an intermediate galactocentric distance. This environment is inconsistent with a young magnetar engine formed during an extreme explosion of a massive star that resulted in a long gamma-ray burst or superluminous supernova. Analysis of a set of 1,863 bursts from the repeating source FRB 20201124A provides evidence of a complicated magnetized site within about an astronomical unit from the source in a barred galaxy.

Constrained by the Nielsen-Ninomiya no-go theorem, in all so-far experimentally determined Weyl semimetals (WSMs) the Weyl points (WPs) always appear in pairs in the momentum space with no exception. As a consequence, Fermi arcs occur on surfaces which connect the projections of the WPs with opposite chiral charges. However, this situation can be circumvented in the case of unpaired WP, without relevant surface Fermi arc connecting its surface projection, appearing singularly, while its Berry curvature field is absorbed by nontrivial charged nodal walls. Here, combining angle-resolved photoemission spectroscopy with density functional theory calculations, we show experimentally that a singular Weyl point emerges in PtGa at the center of the Brillouin zone (BZ), which is surrounded by closed Weyl nodal walls located at the BZ boundaries and there is no Fermi arc connecting its surface projection. Our results reveal that nontrivial band crossings of different dimensionalities can emerge concomitantly in condensed matter, while their coexistence ensures the net topological charge of different dimensional topological objects to be zero. Our observation extends the applicable range of the original Nielsen-Ninomiya no-go theorem which was derived from zero dimensional paired WPs with opposite chirality. In all experimentally observed Weyl semimetals so far, the Weyl points always appear in pairs in the momentum space. Here, the authors report one unpaired Weyl point without surface Fermi arc emerging at the center of the Brillouin zone, which is surrounded by charged Weyl nodal walls in PtGa.

Interleukin (IL)-12 and granulocyte-monocyte colony-stimulating factor (GM-CSF) have recently been used as immunotherapeutic agents in cancer gene therapy. IL-12 and GM-CSF have differential roles in the antitumor immune response, as IL-12 targets T, NK and natural killer T (NKT) cells and GM-CSF principally targets antigen-presenting cells (APCs). To strengthen the therapeutic efficacy of these two cytokines, we generated an oncolytic adenovirus (Ad), Ad-ΔB7/IL12/GMCSF, coexpressing IL-12 and GM-CSF. Using a murine B16-F10 syngeneic tumor model, we show that Ad-ΔB7/IL12/GMCSF promoted antitumor responses and increased survival compared with an oncolytic Ad expressing IL-12 or GM-CSF alone (Ad-ΔB7/IL12 or Ad-ΔB7/GMCSF, respectively). By measuring cytotoxic T lymphocyte activity and interferon-γ production, we show that the enhanced therapeutic effect was mediated by the induction of immune cell cytotoxicity. In situ delivery of Ad-ΔB7/IL12/GMCSF resulted in massive infiltration of CD4 + T cells, CD8 + T cells, NK cells and CD86 + APCs into the tissue surrounding the necrotic area of the tumor. Moreover, GM-CSF effectively promoted antitumor immune memory, which was significantly augmented by IL-12. Lastly, IL12-expressing oncolytic Ads prevented tumor-induced thymic atrophy and was associated with reduced apoptosis and increased proliferation in the thymus. Taken together, these data demonstrate that an oncolytic Ad coexpressing IL-12 and GM-CSF is a potential therapeutic tool for the treatment of cancer.

Fast radio bursts (FRBs) are short pulses observed in the radio band from cosmological distances 1 . One class of models invokes soft gamma-ray repeaters (SGRs), or magnetars, as the sources of FRBs 2 . Some radio pulses have been observed from some magnetars 3 , but no FRB-like events have been detected in association with any magnetar burst, including one giant flare 4 . Recently, a pair of FRB-like bursts (termed FRB 200428) separated by 29 milliseconds were detected from the general direction of the Galactic magnetar SGR J1935+2154 (refs. 5 , 6 ). Here, we report the detection of a non-thermal X-ray burst in the 1–250 keV energy band with the Insight-HXMT satellite 7 , which we identify as having been emitted from SGR J1935+2154. The burst showed two hard peaks with a separation of 34 milliseconds, broadly consistent with that of the two bursts in FRB 200428. The delay time between the double radio peak and the X-ray peaks is about 8.62 s, fully consistent with the dispersion delay of FRB 200428. We thus identify the non-thermal X-ray burst to be associated with FRB 200428, whose high-energy counterpart is the two hard X-ray peaks. Our results suggest that the non-thermal X-ray burst and FRB 200428 share the same physical origin in an explosive event from SGR J1935+2154. Insight-HXMT detected a double-peaked X-ray burst from Galactic magnetar SGR J1935+2154, consistent with two fast radio bursts (FRBs) observed from the same object within seconds. This coincidence suggests a common physical origin, and gives insight into the mechanism behind the origin of FRBs.

Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown physical origin observed at extragalactic distances 1 – 3 . It has long been speculated that magnetars are the engine powering repeating bursts from FRB sources 4 – 13 , but no convincing evidence has been collected so far 14 . Recently, the Galactic magnetar SRG 1935+2154 entered an active phase by emitting intense soft γ-ray bursts 15 . One FRB-like event with two peaks (FRB 200428) and a luminosity slightly lower than the faintest extragalactic FRBs was detected from the source, in association with a soft γ-ray/hard-X-ray flare 18 – 21 . Here we report an eight-hour targeted radio observational campaign comprising four sessions and assisted by multi-wavelength (optical and hard-X-ray) data. During the third session, 29 soft-γ-ray repeater (SGR) bursts were detected in γ-ray energies. Throughout the observing period, we detected no single dispersed pulsed emission coincident with the arrivals of SGR bursts, but unfortunately we were not observing when the FRB was detected. The non-detection places a fluence upper limit that is eight orders of magnitude lower than the fluence of FRB 200428. Our results suggest that FRB–SGR burst associations are rare. FRBs may be highly relativistic and geometrically beamed, or FRB-like events associated with SGR bursts may have narrow spectra and characteristic frequencies outside the observed band. It is also possible that the physical conditions required to achieve coherent radiation in SGR bursts are difficult to satisfy, and that only under extreme conditions could an FRB be associated with an SGR burst. An 8-hour radio observational campaign of the Galactic magnetar SGR 1935+2154, assisted by multi-wavelength data, indicates that associations between fast radio bursts and soft γ-ray bursts are rare.

RNA interference, due to its target specificity, may be highly effective as a novel therapeutic modality, but direct delivery of synthetic small interfering RNA still remains a major obstacle for this approach. To induce long-term expression and specific gene silencing, novel delivery vector system is also required. In this study, we have generated an efficient oncolytic adenovirus (Ad)-based short hairpin (shRNA) expression system (Ad-ΔB7-U6shIL8) against IL-8, a potent proangiogenic factor. To demonstrate IL-8-specificity of this newly engineered Ad-based shRNA, we also manufactured replication-incompetent Ads (Ad-ΔE1-CMVshIL8 and Ad-ΔE1-U6shIL8) under the control of the cytomegalovirus (CMV) and U6 promoters, respectively. Ad-ΔE1-U6shIL8 was highly effective in reducing IL-8 expression, and was much more effective in driving IL-8-specific shRNA than the CMV promoter-driven vector. The reduced IL-8 expression then translated into decreased angiogenesis in vitro as measured by migration, tube formation and rat aortic ring sprouting assays. In addition to its effect on endothelial cells, Ad-ΔE1-U6shIL8 also effectively suppressed the migration and invasion of cancer cells. In vivo , intratumoral injection of Ad-ΔB7-U6shIL8 significantly inhibited the growth of Hep3B and A549 human tumor xenografts. Histopathological analysis of Ad-ΔB7-U6shIL8-treated tumors revealed an increase in apoptotic cells and a reduction in vessel density. Finally, Ad-ΔB7-U6shIL8 was also shown to inhibit the growth of disseminated MDA-MB-231 breast cancer metastases. Taken together, these findings demonstrate the utility and antitumor effectiveness of oncolytic Ad expressing shRNA against IL-8.

Gravitational‐wave high‐energy Electromagnetic Counterpart All‐sky Monitor (GECAM) is a space‐borne instrument dedicated to monitoring high‐energy transients, including Terrestrial Gamma‐ray Flashes (TGFs) and Terrestrial Electron Beams (TEBs). We implemented a TGF/TEB search algorithm for GECAM, with which 147 bright TGFs, 2 typical TEBs and 2 special TEB‐like events are identified during an effective observation time of ∼9 months. We show that, with gamma‐ray and charged particle detectors, GECAM can effectively identify and distinguish TGFs and TEBs, and measure their temporal and spectral properties in detail. A very high TGF‐lightning association rate of ∼80% is obtained between GECAM and GLD360 in east Asia region. Plain Language Summary Terrestrial gamma‐ray flashes (TGFs) and Terrestrial Electron Beams (TEBs) represent the most energetic radioactive phenomena in the atmosphere of the Earth. They reflect a natural particle accelerator that can boost electrons up to at least several tens of mega electron volts and produce gamma‐ray radiation. With novel detection technologies, Gravitational‐wave high‐energy Electromagnetic Counterpart All‐sky Monitor (GECAM) is a new powerful instrument to observe TGFs and TEBs, as well as study their properties. For example, it is difficult for most space‐borne high‐energy instruments to distinguish between TGFs and TEBs. However, we show here that, with the joint observation of gamma‐ray and charged particle detectors, GECAM can effectively identify TGFs and TEBs. GECAM can also reveal their fine features in the light curves and spectra. Key Points During 9‐month observation, Gravitational‐wave high‐energy Electromagnetic Counterpart All‐sky Monitor (GECAM) has detected 147 bright Terrestrial Gamma‐ray Flashes (TGFs), 2 typical Terrestrial Electron Beams (TEBs), and 2 special TEB‐like events With novel detector design, GECAM can effectively classify TGFs and TEBs, and reveal their fine temporal features We obtained a very high TGF‐lightning association rate (∼80%) between GECAM and GLD360 in east Asia region

Gd-doping YBCO films were fabricated on LaAlO 3 (00 l ) substrates by sol–gel method using benzoic acid modified trifluoroacetates precursor solution. Effects of Gd doping on texture, microstructure and flux pinning properties of YBCO films were investigated. With optimal Gd-doping, the surface and texture of YGd x Ba 2 Cu 3 O y films have been improved. The introduction of ion defects can improve the critical current density ( J c ) and flux pinning force ( F p ) of the YGdBCO films. The J c and F p values of YGd 0.1 Ba 2 Cu 3 O y film are almost two times higher than that of pure YBCO film in magnetic field. These results indicate that Gd-doping YBCO phase with sol–gel process is a perspective method for enhancement of current carrying capability of YBCO film.

BaHfO 3 (BHO)-doped YBa 2 Cu 3 O 7− x (YBCO) films have been fabricated on SrTiO 3 (STO) microarray-buffered LaAlO 3 (100) (LAO) substrates by photosensitive sol–gel lithography (PSGL) and chemical solution deposition (CSD). This approach involved the incorporation of secondary-phase additions and substrate decoration to enhance the epitaxial growth of the composite films (YBCO + BHO/STO). The microstructure and texture of YBCO + BHO/STO composite films were analyzed by atomic force microscopy (AFM), optical microscopy (OM), scanning electron microscopy (SEM), and X-ray diffractometer (XRD). The results indicated that the STO microarray interface improved the surface microstructure of the BHO-doped YBCO film and enhanced the in-plane and out-of-plane texture of YBCO films with a high BHO content. Under the influence of STO microarray, a high content of BHO particles could serve as effective flux-pinning centers within the YBCO matrix, leading to a substantial increase in the critical current density under magnetic fields. The YBCO + 10%BHO/STO film exhibited a high critical current density ( J c ) of 3.86 MA/cm 2 at 77 K in a self-field, with maximum pinning force values of 5.4 GN/m 3 at 77 K and 39.8 GN/m 3 at 50 K, respectively. Therefore, the incorporation with the STO microarray buffer was a viable method for enhancing film texture and introducing effective artificial centers to boost superconductivity performances.