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We present a systematic search for changing-look (CL) quasars at high redshift z > 0.9 by crossmatching the spectroscopic data sets from the Dark Energy Spectroscopic Instrument Data Release 1 and Sloan Digital Sky Survey Data Release 18. We identify 97 CL quasars showing significant variability in high-ionization broad emission lines, including 45 turn-on and 52 turn-off events, corresponding to a detection rate of ∼0.042%. The low rate relative to low-ionization CL quasar searches is likely due to selection and physical effects in high-ionization lines. Based on the CL quasar sample, we find that CL quasars generally exhibit lower accretion rates compared to typical quasars, with average Eddington ratios of logλEdd ∼ −1.14 in the bright state and ∼−1.39 in the dim state, compared to ∼−0.65 for typical quasars. Furthermore, while high-ionization lines in CL quasars follow the Baldwin effect on a population level, some sources can display inverse Baldwin trends. In addition, we find a positive correlation between the variability in high-ionization lines (e.g., Mg ii, C iii]) and the change in bolometric luminosity. We also estimate a characteristic rest-frame timescale of ∼3 yr for CL transitions, with no significant difference between turn-on and turn-off cases. Taken as a whole, these findings support an accretion-driven origin of the CL phenomenon, and provide new insights into the variability of high-ionization emission lines.

Objective: The study aimed to evaluate the short-term clinical efficacy of percutaneous full-endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) for lumbar degenerative diseases (LDD). Methods: From July 2020 to July 2021, 93 patients who underwent single-level lumbar fusion procedure were retrospective analysis. The patients were divided into Endo-TLIF group and transforaminal lumbar interbody fusion (TLIF) group. General demographic and perioperative data were recorded, the clinical outcomes were evaluated using visual analogue scale (VAS) and oswestry disability index (ODI). The disk height (DH) was compared between the two groups. Results: All of the surgical procedures were successfully completed, and the patients were followed for a minimum of 2 years. Intraoperative blood loss, drainage volume, time to independent ambulation and hospital length of stay in the Endo-TLIF group were significantly decreased in comparison with the open TLIF group ( p  < 0.05). The VAS for back pain on postoperative 7 day and ODI on postoperative 1 month were lower in the Endo-TLIF group than in the open TLIF group ( P  < 0.05), but no significant difference at 1 year and 2 years postoperatively ( P  > 0.05). The VAS score of leg pain had no demographic statistically significant differences between the groups ( P  > 0.05). The DH were significantly heightened after surgery compared to the preoperative height ( p  < 0.05). Conclusion: Endo-TLIF is a minimally invasive, safety surgery which can achieve comparable short-term effects as open TLIF. It may be a promising option for the treatment of LDD.

In this study, we chose corn stover hemicellulose for the preparation of hydrogels with admirable adsorption properties under mild alkaline conditions. Clay nanosheets were introduced to this system and hemicellulose/clay hybrid hydrogels were prepared. Morphological, mechanical properties and the methylene blue adsorption behaviors of the prepared hydrogels were studied. Results suggested that the addition of clay not only improved the mechanical strength of hemicellulose-based hydrogels, but also increased the adsorption capacity on methylene blue. Moreover, the adsorptions were confirmed to follow pseudo-second order equation for both gels with and without clay. The maximum adsorption capacities on methylene blue for hemicellulose-based hydrogels with or without clay reached 148.8 and 95.6 mg/g, respectively. These results implied that hemicellulose-based hydrogels could be used as promising adsorbents for the removal of methylene blue from waste water.

Extragalactic fast X-ray transients (eFXTs) represent a rapidly growing class of high-energy phenomena, whose physical origins remain poorly understood. With its wide-field, sensitive all-sky monitoring, the Einstein Probe (EP) has greatly increased the discovery rate of eFXTs. The search and identification of the optical counterparts of eFXT are vital for understanding their classification and constraining their physical origin. Yet, a considerable fraction of eFXTs still lack secure classifications due to the absence of timely follow-up observations. We carry out a systematic search of publicly available optical survey data and transient databases (including the Zwicky Transient Facility, ZTF, and the Transient Name Server, TNS) for optical counterparts to eFXT candidates detected by EP. In this paper, we describe our ongoing program and report the first results. Specifically, we identified the eFXT EP240506a to be associated with a UV/optical counterpart, AT 2024ofs. Spectroscopy of its host galaxy with VLT yields a redshift of \\(z = 0.120 \\pm 0.002\\). By combining archival survey data with early-time multiwavelength observations, we find that the luminosity and light-curve evolution of AT~2024ofs are consistent with a core-collapse supernova origin. From detectability simulations, we estimate a local event rate density \\(\\rho_{0}=8.8^{+21.2}_{-3.9}\\ \\mathrm{yr^{-1}\\, Gpc^{-3}}\\) for EP240506a-like events, and completeness-corrected rate of about \\(36\\)--\\(78\\ \\mathrm{yr^{-1}\\ Gpc^{-3}}\\) for EP-detected X-ray transients associated with supernovae. Our results demonstrate the potential of EP to uncover prompt high-energy emission from core-collapse supernovae and underscore the critical importance of timely follow-up of future eFXT events.

Extragalactic fast X-ray transients (eFXTs) represent a rapidly growing class of high-energy phenomena, whose physical origins remain poorly understood. With its wide-field, sensitive all-sky monitoring, the Einstein Probe (EP) has greatly increased the discovery rate of eFXTs. The search for and identification of the optical counterparts of eFXTs are vital for understanding their classification and constraining their physical origin. Yet, a considerable fraction of eFXTs still lack secure classifications due to the absence of timely follow-up observations. We carry out a systematic search of publicly available optical survey data and transient databases (including the Zwicky Transient Facility and the Transient Name Server) for optical counterparts to eFXT candidates detected by EP. In this paper, we describe our ongoing program and report the first results. Specifically, we identified the eFXT EP240506a to be associated with a UV/optical counterpart, AT 2024ofs. Spectroscopy of its host galaxy with the Very Large Telescope yields a redshift of z = 0.120 ± 0.002. By combining archival survey data with early-time multiwavelength observations, we find that the luminosity and light-curve evolution of AT 2024ofs are consistent with a core-collapse supernova origin. From detectability simulations, we estimate a local event rate density ρ0=8.8−3.9+21.2yr−1Gpc−3 for EP240506a-like events, and completeness-corrected rate of about 36–78 yr−1 Gpc−3 for EP-detected X-ray transients associated with supernovae. Our results demonstrate the potential of EP to uncover prompt high-energy emission from core-collapse supernovae and underscore the critical importance of timely follow-up of future eFXT events.

The physical origin of fast radio bursts (FRBs) remains uncertain. Although multiwavelength observations have been widely conducted, only Galactic FRB 20200428D is associated with an X-ray burst from the magnetar SGR J1935+2154. Here we present multiwavelength follow-up observations of the nearby bright FRB 20250316A, including the Five-hundred-meter Aperture Spherical radio Telescope (FAST), Einstein Probe (EP) X-ray mission, Chandra X-ray Observatory, Wide Field Survey Telescope (WFST), and Space Variable Objects Monitor/Visible Telescope (SVOM/VT). The 13.08 hr FAST follow-up campaign without pulse detection requires an energy distribution flatter than those of well-known repeating FRBs, suggesting that this burst is likely a one-off event. A prompt EP follow-up and multiepoch observational campaign totaling >100 ks led to the detection of an X-ray source within the angular resolution of its Follow-up X-ray Telescope (FXT; 10″). A subsequent Chandra observation revealed this source to be offset by 7″ from the FRB position and established a 0.5–10 keV flux upper limit of 7.6 × 10−15 erg cm−2 s−1 at the FRB position, corresponding to ∼1039 erg s−1 at the 40 Mpc distance of the host galaxy NGC 4141. These results set one of the most stringent limits on X-ray emission from a nonrepeating FRB, disfavoring ultraluminous X-ray sources as counterparts of apparently one-off FRBs and offering critical insights into afterglow models. Our study suggests that an arcsecond localization of both the FRB and its potential X-ray counterpart is essential for exploring the X-ray counterpart of an FRB.

Aim： To evaluate the singleand multiple-dose pharmacokinetics of vincristine sulfate liposomes （VSLI） in patients with advanced solid tumors. Methods： In single-dose pharmacokinetic study, 16 patients were administered VSLI （1.5, 2.0, or 2.3 mg.m-2） through intravenous infusion. Another 6 patients receiving vincristine sulfate （VCR, 2.0 mg） were taken as the control. In multiple-dose pharmacokinetic study, 12 patients were administered VSLI （1.5 or 1.8 mg.m-2） through intravenous infusion weekly for 4 consecutive weeks. The plasma concentration of VSLI was determined using the liquid chromatography-tandem mass spectrometry （LC-MS/MS） method. Results： After intravenous infusion of the single dose of VSLI, the plasma concentrations were characterized by bi-exponential decline curves. No statistically significant differences were observed between the main pharmacokinetic parameters in the 3 dose groups. Compared with the patients receiving VCR, the patients treated with VSLI displayed an increase in the area under the plasma concentration vs time curve （AUC）, and a decrease in plasma clearance rates. On the 4th cycle in the multiple-dose study, the plasma concentration of VCR in all subjects prior to the weekly administration was below the lower limit of quantification （LLOQ）. The calculated pharmacokinetic parameters from the subjects in the multipleand single-dose （1.5 mg.m 2） groups had no significant differences. Although the administration of liposomal VCR may significantly elevate the plasma concentration of VCR, VSLI-associated adverse events were similar to those associated with conventional VCR. Conclusion： VSLI exhibits a lower clearance and a higher AUC compared with conventional VCR. No accumulation was observed in patients exposed to VSLI for 4 consecutive weeks. VSLI was generally tolerated in the subjects. The phase Ⅱdose of VSLI may be recommended as 4 doses of 1.5 mg.m-2 for treatment of patients with advanced solid tumors.

Background： At present, a diagnostic tool with high specificity for impaired endometrial receptivity, which may lead to implantation failure, remains to be developed. We aimed to assess the different endometrial microRNA （miRNA） signatures for impaired endometrial receptivity by microarray analysis. Methods： A total of 12 repeated implantation failure （RIF） patients and I0 infertile patients, who conceived and delivered after one embryo transfer attempt, were recruited as RIF and control groups, respectively. Endometrial specimens from the window of implantation （WOI） were collected from these two groups. MiRNA microarray was conducted on seven and five samples from the RIF and control groups, respectively. Comparative, functional, and network analyses were performed for the microarray results. Quantitative real-time polymerase chain reaction （PCR） was performed on other samples to validate the expression of specific miRNAs. Results： Compared with those in the control group, the expression levels of 105 miRNAs in the RIF group were found to be significantly up- or down-regulated （at least 2-fold） by microarray analysis. The most relevant miRNA functional sets of these dysregulated miRNAs were miR-30 family, human embryonic stern cell regulation, epithelial-mesenchymal transition, and miRNA tumor suppressors by tool for annotations ofmicroRNA analysis. Network regulatory analysis found 176 miRNA-mRNA interactions, and the top 3 core miRNAs were has-miR-4668-5p, has-miR-429, and has-miR-5088. Expression levels of the 18 selected miRNAs in new samples by real-time PCR were found to be regulated with the same trend, as the result ofmicroarray analysis. Conclusions： There is a significant different expression of certain miRNAs in the WOI endometrium for RIF patients. These miRNAs may contribute to impaired endometrial receptivity.

We present a systematic search for changing-look (CL) quasars at high redshift z > 0.9 by cross-matching the spectroscopic datasets from the Dark Energy Spectroscopic Instrument Data Release 1 and Sloan Digital Sky Survey Data Release 18. We identify 97 CL quasars showing significant variability in high-ionization broad emission lines, including 45 turn-on and 52 turn-off events, corresponding to a detection rate of approximately 0.042%. This rate is lower than that found for low-ionization CL quasars, likely due to both selection effects and physical differences in high-ionization lines. Based on the CL quasar sample, we find that CL quasars generally exhibit lower accretion rates compared to typical quasars, with average Eddington ratios of log lambda_Edd approximately -1.14 in the bright state and approximately -1.39 in the dim state, compared to approximately -0.65 for typical quasars. While high-ionization lines in CL quasars follow the Baldwin effect on a population level, some individual sources show inverse Baldwin trends. We also find a positive correlation between the variability of high-ionization lines such as Mg II and C III] and the change in bolometric luminosity. In addition, we estimate a characteristic rest-frame timescale of approximately 3 years for CL transitions, with no significant difference between turn-on and turn-off cases. Taken together, these results support an accretion-driven origin for the CL phenomenon and provide new insights into the variability of high-ionization emission lines.

Compact object mergers are multi-messenger sources and progenitors of some gamma-ray bursts (GRBs), primarily understood by gamma-ray observations, while poorly constrained in the prompt low-energy phase. A long-lasting X-ray emission was discussed as afterglows following several short-duration (\\(\\lesssim\\)2 s) bursts, yet this prompt X-ray component was not directly observed or confirmed. Here we report the discovery of a minutes-long (\\(\\sim\\)560 s) flash of soft X-rays immediately following the short (\\(\\sim\\)0.4 s) GRB 250704B. The long-soft bump points to a distinct phase of prompt emission in X-rays detected by Einstein Probe in an event that otherwise appear as an ordinary short GRB, showing that long-lasting X-ray emission is likely a common feature of merger-driven bursts and a promising electromagnetic counterpart to gravitational-wave sources.