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The Lobster Eye Imager for Astronomy (LEIA) is the pathfinder of the wide-field X-ray telescope used in the Einstein Probe mission. In this study, we present an image of the Virgo Cluster taken by LEIA in the 0.5–4.5 keV band with an exposure time of ∼17.3 ks in the central region. This extended emission is generally consistent with the results obtained by ROSAT. However, the field is affected by bright point sources due to the instrument's Point Spread Function (PSF) effect. Through fitting of the LEIA spectrum of the Virgo Cluster, we obtained a temperature of 2. 1 − 0.1 + 0.3 keV, which is consistent with the XMM-Newton results (∼2.3 keV). Above 1.6 keV, the spectrum is dominated by the X-ray background. In summary, this study validates LEIA's extended source imaging and spectral resolution capabilities for the first time. [ABSTRACT FROM AUTHOR]

Pseudorabies virus (PRV) primarily infects swine and has several secondary hosts, including cattle, dogs, and cats. PRV, also called Aujeszky disease virus or Suid herpesvirus 1, is a member of [...]

In this original study, we retrospectively reviewed the cases of nocardiosis diagnosed through culture and next-generation sequencing (NGS) methods between 2014 and 2018 in Huashan Hospital and found out that the latter way can not only improve the detection rate of Nocardia spp. but also greatly reduce the turnaround time. In addition, by comparing nocardiosis and non-nocardiosis patients both of whose samples had Nocardia spp. detected by NGS, we found that Nocardia 's specific reads ranking among top two might be a satisfactory cutoff value for clinical diagnosis of the disease. Our study introduced the promising value of the NGS method in the rapid diagnosis of nocardiosis. [ABSTRACT FROM AUTHOR]

Characterizing the long-term variability of active galactic nuclei (AGNs) is a key legacy of the Rossi X-ray Timing Explorer (RXTE). We carry out a spectral analysis on a sample of 20 Seyfert 1 galaxies, which had been observed by the RXTE for at least 100 times. All 18 335 spectra are fitted in a uniform way using a power-law component plus an additional Gaussian line when necessary. For any source in our sample, we confirm that the spectrum softens or the photon index, Γ, increases with increasing the 2–10 keV luminosity, L X. However, different source holds distinct Γ– L X/ L Edd relation, rather than a common one. We also fit the correlation with a function of Γ = C + β × log (flux), where C is a constant and parameter β is the slope of the correlation. In this way, the increase speed of the Γ– L X/ L Edd relation can be depicted with the parameter β. Since our sample contains a large sample of long-term monitored sources, it allows us to explore the second-order effect of spectral evolution. We find that there is an anticorrelation between β and the X-ray Eddington ratio, L X/ L Edd. That is, the increasing tendency of Γ with increasing X-ray luminosity becomes slower when the source has a larger X-ray Eddington ratio. Our results may indicate changes in the geometry and/or the viscosity parameter of the accretion disc at different Eddington ratios. [ABSTRACT FROM AUTHOR]

The Be X-ray pulsar (BeXRP) SXP 59 underwent a giant outburst in 2017 with a peak X-ray luminosity of 1.1 × 1038 erg s−1. We report on the X-ray behaviour of SXP 59 with the XMM–Newton and NuSTAR observations collected at the outburst peak, decay, and the low luminosity states. The pulse profiles are energy dependent, the pulse fraction increases with the photon energy and saturates at 65 per cent above 10 keV. It is difficult to constrain the change in the geometry of emitting region with the limited data. Nevertheless, because the pulse shape generally has a double-peaked profile at high luminosity and a single peak profile at low luminosity, we prefer the scenario that the source transited from the super-critical state to the sub-critical regime. This result would further imply that the neutron star (NS) in SXP 59 has a typical magnetic field. We confirm that the soft excess revealed below 2 keV is dominated by a cool thermal component. On the other hand, the NuSTAR spectra can be described as a combination of the non-thermal component from the accretion column, a hot blackbody emission, and an iron emission line. The temperature of the hot thermal component decreases with time, while its size remains constant (R ∼ 0.6 km). The existence of the hot blackbody at high luminosity cannot be explained with the present accretion theories for BeXRPs. It means that either more sophisticated spectral models are required to describe the X-ray spectra of luminous BeXRPs, or there is non-dipole magnetic field close to the NS surface. [ABSTRACT FROM AUTHOR]

Multiple myeloma (MM) is a cancer that occurs in plasma cells, which fall under the category of white blood cells that are in charge of antibody production. According to previous studies, microRNA-497 (miR-497) functions as a tumor suppressor in several types of cancer, including gastric cancer and colorectal cancer. Therefore, the present study aims to investigate the effects of miR-497 on cellular function of human MM cells through the mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) signaling pathway by targeting Raf-1. The differentially expressed genes and miRs in MM, and the relationship between the miR and gene were verified. It was found that Raf-1 was a target gene of miR-497. The data obtained from MM tissues showed increased Raf-1 level and decreased miR-497 level. MM cells were treated with mimic, inhibitor and siRNA in order to evaluate the role of miR-497, Raf-1 and MAPK/ERK in MM. The expression pattern of miR-497, Raf-1, ERK1/2, survivin, B-cell lymphoma-2 (Bcl-2) and BCL2-Associated X (Bax) as well as the extent of ERK1/2 phosphorylation were determined. Retored miR-497 and si-Raf-1 resulted in increases in the Bax expression and cell apoptosis and decreases in the expressions of Raf-1, MEK-2, survivin, Bcl-2, along with the extent of ERK1/2 phosphorylation. In addition, the biological function evaluations of MM cells revealed that miR-497 mimic or si-Raf-1 led to suppression in cell proliferation, invasion and migration. In conclusion, our results have demonstrated that miR-497 targets Raf-1 in order to inhibit the progression of MM by blocking the MAPK/ERK signaling pathway. [ABSTRACT FROM AUTHOR]

Multiple reassortant strains of novel, highly pathogenic avian influenza A have recently emerged and spread over the world. Here we report on a 68-year-old woman in Jiangsu, China, with influenza A(H7N4) infection and associated illness, which strongly demonstrating the ability of the virus to spread from animals to humans and thus emphasizing the importance of continuous surveillance of the emerging viruses. [ABSTRACT FROM AUTHOR]

We report human endophthalmitis caused by pseudorabies virus infection after exposure to sewage on a hog farm in China. High-throughput sequencing and real-time PCR of vitreous humor showed pseudorabies virus sequences. This case showed that pseudorabies virus might infect humans after direct contact with contaminants. [ABSTRACT FROM AUTHOR]

The Be X-ray pulsar SMC X-3 underwent an extra long and ultraluminous giant outburst from 2016 August to 2017 March. The peak X-ray luminosity is up to ∼1039erg/s, suggesting a mildly super-Eddington accretion onto the strongly magnetized neutron star. It therefore bridges the gap between the Galactic Be/X-ray binaries (LXpeak≤1038erg/s) and the ultraluminous X-ray pulsars (LXpeak≥1040erg/s) found in nearby galaxies. A number of observations were carried out to observe the outburst. In this paper, we perform a comprehensive phase-resolved analysis on the high quality data obtained with the Nustar and XMM-Newton, which were observed at a high and intermediate luminosity levels. In order to get a better understanding on the evolution of the whole extreme burst, we take the Swift results at the low luminosity state into account as well. At the early stage of outburst, the source shows a double-peak pulse profile, the second main peak approaches the first one and merges into the single peak at the low luminosity. The second main peak vanishes beyond 20 keV, and its radiation becomes much softer than that of the first main peak. The line widths of fluorescent iron line vary dramatically with phases, indicating a complicated geometry of accretion flows. In contrast to the case at low luminosity, the pulse fraction increases with the photon energy. The significant small pulse fraction detected below 1 keV can be interpreted as the existence of an additional thermal component located at far away from the central neutron star. [ABSTRACT FROM AUTHOR]