Fast radio bursts (FRBs) are millisecond-duration radio transients
of unknown origin. Two possible mechanisms that could generate extremely coherent emission from FRBs invoke neutron star ...magnetospheres
or relativistic shocks far from the central energy source
. 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
or variable polarization angles in some other apparently one-off events
. 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.
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FZAB, GEOZS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract
Superconductivity in the cuprates is found to be intertwined with charge and spin density waves. Determining the interactions between the different types of order is crucial for ...understanding these important materials. Here, we elucidate the role of the charge density wave (CDW) in the prototypical cuprate La
1.885
Sr
0.115
CuO
4
, by studying the effects of large magnetic fields (
H
) up to 24 Tesla. At low temperatures (
T
), the observed CDW peaks reveal two distinct regions in the material: a majority phase with short-range CDW coexisting with superconductivity, and a minority phase with longer-range CDW coexisting with static spin density wave (SDW). With increasing magnetic field, the CDW first grows smoothly in a manner similar to the SDW. However, at high fields we discover a sudden increase in the CDW amplitude upon entering the vortex-liquid state. Our results signify strong coupling of the CDW to mobile superconducting vortices and link enhanced CDW amplitude with local superconducting pairing across the
H
−
T
phase diagram.
Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown physical origin observed at extragalactic distances
. It has long been speculated that magnetars are the engine powering ...repeating bursts from FRB sources
, but no convincing evidence has been collected so far
. Recently, the Galactic magnetar SRG 1935+2154 entered an active phase by emitting intense soft γ-ray bursts
. 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
. 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.
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FZAB, GEOZS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The molecular characterization of cytogenetic abnormalities has not only provided insights into the mechanisms of leukemogenesis but also led to the establishment of new treatment strategies ...targeting these abnormalities and thereby further improve the prognosis of patients. We analyzed the prognosis of 1091 Chinese patients with newly diagnosed acute lymphoblastic leukemia (ALL) and explored the prognostic impacts of a large number of cytogenetic/molecular abnormalities. It was demonstrated that, in both B- and T-ALL settings, the prognosis was negatively correlated to the age as reported to date. For childhood T-ALL patients, it was also documented that the HOX11 expression represented a favorable prognostic factor as it was in adult ones. We identified CRLF2 overexpression as an intermediate-risk marker and Ik6 variant of IKZF1 gene as a high-risk one when stratifying pediatric B-ALL cases according to cytogenetic/molecular risks. We also found that Ik6 variant and CRLF2 overexpression had an important role in dictating the prognosis of Ph-negative patients, which may be useful markers in guiding the treatment of ALL in the future, with tyrosine kinase inhibitors on the other hand reversing the fate of Ph-positive ALL patients.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Global satellite observations of temperature and geopotential height (GPH) from the Microwave Limb Sounder (MLS) on the EOS Aura spacecraft are discussed. The precision, resolution, and accuracy of ...the data produced by the MLS version 2.2 processing algorithms are quantified, and recommendations for data screening are made. Temperature precision is 1 K or better from 316 hPa to 3.16 hPa, degrading to ∼3 K at 0.001 hPa. The vertical resolution is 3 km at 31.6 hPa, degrading to 6 km at 316 hPa and to ∼13 km at 0.001 hPa. Comparisons with analyses (Goddard Earth Observing System version 5.0.1 (GEOS‐5), European Centre for Medium‐range Weather Forecasts (ECMWF), Met Office (MetO)) and other observations (CHAllenging Minisatellite Payload (CHAMP), Atmospheric Infrared Sounder/Advanced Microwave Sounder Unit (AIRS/AMSU), Sounding of the Atmosphere using Broadband Radiometry (SABER), Halogen Occultation Experiment (HALOE), Atmospheric Chemistry Experiment (ACE), radiosondes) indicate that MLS temperature has persistent, pressure‐dependent biases which are between −2.5 K and +1 K between 316 hPa and 10 hPa. The 100‐hPa MLS v2.2 GPH surface has a bias of ∼150 m relative to the GEOS‐5 values. These biases are compared to modeled systematic uncertainties. GPH biases relative to correlative measurements generally increase with height owing to an overall cold bias in MLS temperature relative to correlative temperature measurements in the upper stratosphere and mesosphere.
We report results on the searches of weakly interacting massive particles (WIMPs) with sub-GeV masses (mχ) via WIMP-nucleus spin-independent scattering with Migdal effect incorporated. Analysis on ...time-integrated (TI) and annual modulation (AM) effects on CDEX-1B data are performed, with 737.1 kg day exposure and 160 eVee threshold for TI analysis, and 1107.5 kg day exposure and 250 eVee threshold for AM analysis. The sensitive windows in mχ are expanded by an order of magnitude to lower DM masses with Migdal effect incorporated. New limits on σχNSI at 90% confidence level are derived as 2×10−32∼7×10−35 cm2 for TI analysis at mχ∼50–180 MeV/c2, and 3×10−32∼9×10−38 cm2 for AM analysis at mχ∼75 MeV/c2–3.0 GeV/c2.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM
The dispersive sweep of fast radio bursts (FRBs) has been used to probe the ionized baryon content of the intergalactic medium
, which is assumed to dominate the total extragalactic dispersion. ...Although the host-galaxy contributions to the dispersion measure appear to be small for most FRBs
, in at least one case there is evidence for an extreme magneto-ionic local environment
and a compact persistent radio source
. Here we report the detection and localization of the repeating FRB 20190520B, which is co-located with a compact, persistent radio source and associated with a dwarf host galaxy of high specific-star-formation rate at a redshift of 0.241 ± 0.001. The estimated host-galaxy dispersion measure of approximately Formula: see text parsecs per cubic centimetre, which is nearly an order of magnitude higher than the average of FRB host galaxies
, far exceeds the dispersion-measure contribution of the intergalactic medium. Caution is thus warranted in inferring redshifts for FRBs without accurate host-galaxy identifications.
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FZAB, GEOZS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Background
The aim of this study was to evaluate whether adjuvant chemotherapy is associated with improved survival in patients with resectable gastric neuroendocrine carcinomas (G‐NECs) or mixed ...adenoneuroendocrine carcinomas (G‐MANECs).
Methods
The study included patients with G‐NECs or G‐MANECs who underwent surgery in one of 21 centres in China between 2004 and 2016. Propensity score matching analysis was used to reduce selection bias, and overall survival (OS) in different treatment groups was estimated by the Kaplan–Meier method.
Results
In total, 804 patients with resectable G‐NECs or G‐MANECs were included, of whom 490 (60·9 per cent) received adjuvant chemotherapy. After propensity score matching, OS in the chemotherapy group was similar to that in the no‐chemotherapy group. Among patients with G‐NECs, survival in the fluorouracil (5‐FU)‐based chemotherapy group and the non‐5‐FU‐based chemotherapy group was similar to that in the no‐chemotherapy group. Similarly, etoposide plus cisplatin or irinotecan plus cisplatin was not associated with better OS in patients with G‐NECs. Among patients with G‐MANECs, OS in the non‐5‐FU‐based chemotherapy group was worse than that in the no‐chemotherapy group. Patients with G‐MANECs did not have better OS when platinum‐based chemotherapy was
used.
Conclusion
There was no survival benefit in patients who received adjuvant chemotherapy for G‐NECs or G‐MANECs.
Antecedentes
El objetivo de este estudio fue evaluar si la quimioterapia adyuvante mejoraba la supervivencia en pacientes con carcinomas gástricos resecables neuroendocrinos (gastric neuroendocrine carcinomas, G‐NECs) y carcinomas adenoneuroendocrinos mixtos (mixed adenoneuroendocrine carcinomas, G‐MANECs).
Métodos
Se incluyeron pacientes con G‐NECs y G‐MANECs tratados quirúrgicamente en 21 centros en China entre 2004 y 2016. Se utilizó un análisis de emparejamiento por puntaje de propensión para reducir el sesgo de selección y el método de Kaplan‐Meier para estimar la supervivencia global (overall survival, OS) de los pacientes en los diferentes grupos de tratamiento.
Resultados
En total, se incluyeron en el estudio 804 pacientes con G‐NECs y G‐MANECs resecables y 490 pacientes (60,9%) recibieron quimioterapia adyuvante. Después del emparejamiento por puntaje de propensión, la OS del grupo con quimioterapia fue similar a la del grupo sin quimioterapia. En los pacientes con G‐NECs, la supervivencia en los grupos con quimioterapia basada en 5‐FU (fluorouracilo) y de quimioterapia sin 5‐FU fue similar a la del grupo sin quimioterapia. Asimismo, la combinación de etopósido y cisplatino o de irinotecán y cisplatino no se asoció con una mejor OS en pacientes con G‐NECs. En pacientes con G‐MANECs, la OS del grupo con quimioterapia sin 5‐FU fue peor que la del grupo sin quimioterapia. Los pacientes con G‐MANECs no presentaron una mejor OS cuando se administró quimioterapia basada en platinos.
Conclusión
La administración de quimioterapia adyuvante en pacientes con G‐NECs y G‐MANECs no mejoró la supervivencia.
This multicentre study enrolled 804 patients with resectable gastric neuroendocrine carcinomas and gastric mixed adenoneuroendocrine carcinomas. In propensity score matching analysis, there were no associations between the use of adjuvant chemotherapy and improved overall survival. Similar results were obtained in stratified analysis according to different chemotherapy regimens.
No benefit
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Immunity acquired from infection or vaccination protects humans from symptomatic hepatitis E. However, whether the risk of hepatitis E virus (HEV) infection is reduced by the immunity remains ...unknown. To understand this issue, a cohort with 12 409 participants randomized to receive the hepatitis E vaccine Hecolin® or placebo were serologically followed up for 2 years after vaccination. About half (47%) of participants were initially seropositive. A total of 139 infection episodes, evidenced by four-fold or greater rise of anti-HEV level or positive seroconversion, occurred in participants who received three doses of treatment. Risk of infection was highest among the baseline seronegative placebo group participants (2.04%). Pre-existing immunity and vaccine-induced immunity lower the risk significantly, to 0.52% and 0.30%, respectively. In conclusion, both vaccine-induced and naturally acquired immunity can effectively protect against HEV infection.
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BFBNIB, DOBA, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, UILJ, UKNU, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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