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The environmental problems caused by microplastics (MPs) are becoming more serious. Sediments are important environmental assets and tend to accumulate MPs and nitrogen (N). Microbes are crucial for the cycling of N in benthic ecosystems, and the presence of MPs can alter the microbial community and N transformation. Moreover, various factors can significantly impact the N availability regulated by MPs, including their type, size, and concentration, by interfering with microbial diversity, enzyme activities and related coding genes. This paper mainly reviews the research progresses on the impacts of MPs in sediment coupled with the contribution of biofilm. Furthermore, the response and mechanism of MPs to microorganism-mediated N cycling, such as ammonia oxidation, denitrification, and N fixation, are spotlighted as areas of primary concern along with the role of MPs in accelerating or impeding the N cycle. Finally, the research gaps that require further multidisciplinary investigations are raised. The knowledge gained from this review will provide insights into the detrimental impacts of MPs on benthic ecosystem and urge future research to establish different approaches about formation of MPs-biofilm under different environmental scenarios to evaluate the multidimensional impacts.

With the advancement of machine learning techniques, data-driven power system dynamic security assessment (DSA) has received great research interests. Traditional methods usually apply one DSA model for one specific fault and cannot simultaneously address different multiple faults by one model. To solve this issue and further improve the DSA accuracy performance, this paper proposes a novel DSA method based on multi-label learning (MLL) with a training database for sufficient and incomplete/uneven coverage labels scenarios. By considering fault correlation between different faults, the proposed MLL-based DSA method can handle multiple faults simultaneously with the high stability assessment accuracy performance. Moreover, this paper provides the detailed optimization process and tight mathematical proof for the proposed MLL-based DSA method. Comprehensive simulation tests and comparisons were conducted on the New England 10-machine 39-bus testing system and the synthetic Illinois 49-machine 200-bus testing system.

Low-dimension perovskite materials have attracted wide attention due to their excellent optical properties and stability. Herein, Sb3+-doped Cs2ZrCl6crystals are synthesized by a coprecipitation method in which Sb3+ions partially replace Zr4+ions. The Cs2ZrCl6:xSb3+powder shows blue and orange–red emissions under a 254 and 365 nm light, respectively, due to the [ZrCl6]2–octahedron and [SbCl6]3–octahedron. The photoluminescence quantum yield (PLQY) of Cs2ZrCl6:xSb3+(x= 0.1) crystals is up to 52.5%. According to experimental and computational results, the emission mechanism of the Cs2ZrCl6:xSb3+crystals is proposed. On the one hand, a wide blue emission with a large Stokes shift is caused by the self-trapping excitons of [ZrCl6]2–octahedra under a 260 nm excitation. On the other hand, the luminescence mechanism of [SbCl6]3–octahedron is divided into two parts: 1P1→ 1S0(490 nm) and 3P1→ 1S0(625 nm). The broad-band emission, high PLQY, and excellent stability endow the Cs2ZrCl6:xSb3+powders with the potential for the fabrication of white light-emitting diodes (WLEDs). A WLED device is fabricated using a commercial 310 nm NUV chip, which shows a high color rendering index of 89.7 and a correlated color temperature of 5333 K. In addition, the synthesized Cs2ZrCl6:xSb3+crystals can be also successfully used for information encryption. Our work will provide a deep understanding of the photophysical properties of Sb3+-doped perovskites and facilitate the development of Cs2ZrCl6:xSb3+crystals in encrypting multilevel optical codes and WLEDs.

Aiming at timely and adaptive remedial control for the fault-induced voltage recovery (FIDVR) events in power systems, this paper develops a probabilistic data-driven method for response-based load shedding (RLS). In the proposed method, a scalable Gaussian process (SGP) model is developed to estimate the required load shedding (LS) amount and the confidence of the corresponding predictions. Based on the probabilistic information, a 2-stage LS process is designed to enhance the effectiveness and efficiency of the scheme, using the mean value for LS at the first stage and the upper-bound value for LS at the second stage. The 1st stage shed the amount of load with the largest likelihood, aiming to alleviate system stress with the least control cost. The 2nd stage serves as a safety net to ensure system stability considering the possible prediction error. Compared with the conventional RLS schemes and other state-of-the-art approaches, simulation results verify that the proposed method can effectively mitigate FIDVR with a much less load shedding amount.

The aim of the case control study was to compare surgical outcomes of transvaginal natural orifice transluminal endoscopic surgery (vNOTES) hysterectomy with the da Vinci surgical system (dVSS) and conventional vNOTES. A case control study was performed on 25 cases in our hospital. Patients (n = 8) who underwent vNOTES hysterectomy with dVSS were selected to compare with the control group (n = 17) consisted of patients who underwent conventional vNOTES. Patients in the 2 groups underwent different operations respectively, and no case was transferred to transabdominal laparoscopy. In the conventional vNOTES group, 1 patient happened intraoperative hemorrhage of about 1000 mL, and was treated with blood transfusion, and the other one of vNOTES hysterectomy with dVSS had poor incision healing within 1 month after surgery. The other patients had no intraoperative and postoperative complications. The difference of pain scores on the first day (P = .006) and the third day (P = .045) after the 2 surgical methods differed significantly. No statistical differences were observed in operation time, median hospital stay, blood loss, decreased hemoglobin 3 days after surgery, and postoperative white blood cell count. vNOTES hysterectomy with dVSS is safe and feasible, and can achieve the same effect as the conventional vNOTES hysterectomy. And this method may alleviate the pain of patients.

A novel 2D/2D Bi 2 MoO 6 /g-C 3 N 4 step-scheme (S-scheme) composite by loading Au as cocatalyst was successfully fabricated using a photoreduction and hydrothermal route. The obtained Bi 2 MoO 6 /g-C 3 N 4 /Au photocatalysts were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photo-electron spectroscopy (XPS), UV–vis diffuse reflectance spectra (UV–vis), Fourier transform infrared spectroscopy (FTIR), photoluminescence (PL), photocurrent response(I - t), and electrochemical impedance spectroscopy (EIS). The HRTEM images revealed that an intimate interface in composites were formed. The optimum photocatalytic activity of Rhodamine B degradation over Bi 2 MoO 6 /g-C 3 N 4 /Au was about 9.7 times and 13.1 times as high as those of Bi 2 MoO 6 and g-C 3 N 4 , respectively. The notably improved photocatalytic activity of Bi 2 MoO 6 /g-C 3 N 4 /Au could be mainly ascribed to the abundant active sites and the enhanced separation efficiency of photogenerated carriers in Bi 2 MoO 6 /g-C 3 N 4 S-scheme system. Notably, Au nanoparticles could act as a co-catalyst to further promote electron transfer and separation from the conduction band of g-C 3 N 4. Additionally, a possible step-scheme photocatalytic reaction mechanism of RhB degradation over Bi 2 MoO 6 /g-C 3 N 4 /Au was tentatively proposed. PL and transient photocurrent analysis implied that Bi 2 MoO 6 /g-C 3 N 4 /Au photocatalysts possessed the lower recombination rate of photogenerated carriers compared with pure Bi 2 MoO 6 and g-C 3 N 4 , respectively. The present work is expected to provide useful information in designing 2D/2D S-scheme heterojunction photocatalysts. [ABSTRACT FROM AUTHOR]

Highly dispersed Cu–ZnO nanoparticles supported on ordered mesoporous carbon, which had a 2D hexagonal structure, uniform pore size, and high surface area, were synthesized through template method. We describe the formation, structures, and properties of the mesoporous carbon‐supported catalysts and investigate the effect of the synthesis conditions on the catalyst morphology. A new catalyst with uniformly distributed metal oxide is synthesized and characterized. The active centers Cu–ZnO of the designed catalyst are well distributed in the ordered mesoporous carbon FDU‐15 which has very high BET surface area and large pore volume. The effects of the amount of metal oxide loading, calcination temperature, and ramping rate on the resulting catalysts are investigated using N2‐physisorption, X‐ray diffraction, and scanning and electron microscopy. The results show that the Cu–ZnO particle size increases with the metal loading and calcination temperature, whereas it decreases with the ramping rate. When the metal loading is 20%, the calcination temperature is 700 °C, and the ramping rate is 20 °C/min, uniform metal oxide particles well distributed on the carbon support are obtained.

Metal halide perovskite materials have highly attracted wide attention for lighting applications because of their unique optoelectronic properties. However, the complex preparation processes and the toxicity of lead have limited their practical applications. There are few reports on zero-dimensional (0D) organic/inorganic tin-based perovskites with both good stability and a high photoluminescence quantum yield (PLQY). Here, Sb3+doping and Bi3+doping of 0D (NH4)2SnCl6perovskite powders are reported. Sb3+doping of 0D (NH4)2SnCl6perovskites shows wide emission peaks at 530 and 640 nm with a PLQY of up to 17.03%, while Bi3+doping of 0D (NH4)2SnCl6perovskites exhibits a broad blue emission at 460 nm with a PLQY of 4.40%. Combining experimental results and theoretical calculations, we propose that the mechanism of Sb3+ion doping of 0D (NH4)2SnCl6perovskites is a P1→ 1S0transition (singlet) at 530 nm and a 3P1→ 1S0transition (triplet) at 640 nm. However, the mechanism of Bi3+ion doping of 0D (NH4)2SnCl6perovskites is a 3P1→ 1S0transition at 460 nm. In addition, both metal ion dopings of 0D (NH4)2SnCl6perovskites have good air and thermal stability. We demonstrate that the Sb3+doping and Bi3+doping of 0D (NH4)2SnCl6perovskite phosphors have great potential for solid-state lighting.

Meteorological and soil drought is disastrous to natural and social systems. It is expected that the occurrence of meteorological and soil drought compound events will become more frequent and extreme in the future. The propagation process of meteorological drought to soil drought plays an essential role in the occurrence of drought. However, the drought propagation process is not clear, especially the quantification of drought characteristic propagation process is rarely realized. This study constructs drought intensity propagation index (DIP) and drought duration propagation index (DDP), and then puts forward drought propagation partition in China. Furthermore, this study preliminarily discussed the driving factors of drought propagation and the relationship between land‐atmosphere interaction and main drought propagation partition (arid type drought propagation area, peer‐to‐peer type drought propagation area, and humid type drought propagation area). The results show that DDP and DIP are significantly negatively correlated in China from 1981 to 2020. From southeast to northwest, the propagation of drought intensity from meteorological drought to soil drought gradually increased and the propagation of drought duration gradually decreased. We further concluded that 68% of regions with similar intensity and duration of meteorological drought and soil drought (peer‐to‐peer type drought propagation area) are concentrated in semiarid and dry subhumid, which is exactly the area with strong land‐atmosphere interaction. In all land use types, grasslands are most prone to peer‐to‐peer propagation of drought. This study further reveals the law and mechanism of drought propagation and provides a new idea and attempt to clarify the drought propagation process. Drought intensity propagation index and drought duration propagation index for quantifying drought propagation characteristics are proposedDividing drought propagation partitionDiscovery of drought propagation close peer‐to‐peer in areas with strongest land‐atmosphere coupling Drought intensity propagation index and drought duration propagation index for quantifying drought propagation characteristics are proposed Dividing drought propagation partition Discovery of drought propagation close peer‐to‐peer in areas with strongest land‐atmosphere coupling

The molecular mechanisms of esophageal squamous cell carcinoma (ESCC) remain poorly understood. The transmembrane emp24 trafficking protein 3 (TMED3) acts as an oncogene or tumor suppressor gene in different cancers. Our study was to explore the clinicopathological significance and functional roles of TMED3 in ESCC.

In this study, the purification of crocin-I from Gardenia yellow by macroporous resin columns in-series was systematically investigated. The in-series macroporous adsorption resins consisting of XAD 4 and XAD 1600N resins were selected on the basis of the evaluation of performance and separation characteristics of 17 kinds of resins, including the adsorption capacities, desorption ratio, and separation degree. According to the analysis results, the optimum conditions were as follows: bed volume ratio of XAD 4 and XAD 1600N resins, sample volume, flow rate, and methanol concentration were 3 : 1, 5 BV, 15 BV/h, and 70%, respectively (BV was the bed volume of XAD 4 resin). After one run treatment, the separation degree of crocin-I at 254 nm and 440 nm decreased from 1.92 to 0.08 (DC−254 nm) and from 0.71 to 0.36 (DC−440 nm), respectively. The results showed that the in-series macroporous resins revealed a high capacity in the purification of crocin-I. Meanwhile, in the animal experiment, the forced swimming tests were regulated by crocin-I and Gardenia yellow, which demonstrated that crocin-I was the main constituent of Gardenia yellow and had potential antidepressant biological activities.

Crocus sativus L. is commonly used as functional food and medicinal herb in traditional Chinese medicine. In this study, the spectrum–effect relationship was established between HPLC fingerprints and in vitro antioxidant activity of saffron to improve the quality evaluation method of saffron. The fingerprints of 21 batches of saffron collected from different regions were assessed, and the data were further analyzed by chemometric methods, including similarity analysis, hierarchical clustering analysis, principal component analysis, and orthogonal partial least squares discriminant analysis. The spectrum–effect relationship between fingerprints and antioxidant effect of saffron was analyzed by grey relational analysis and partial least square methods to figure out the antioxidant component of saffron. Thirteen common peaks of 21 batches of saffron were included in the analysis, and peak 3 (picrocrocin), peak 7 (crocin I), and peak 10 (crocin II) were identified as the main active components responsible for antioxidant efficacy. Besides, a multi-index quality control method was developed for simultaneous determination of these three antioxidant components in saffron. Taken together, this study provided new strategies for the quality control and the development of new bioactive products of saffron in the future.

The mechanisms by which Y chromosome microdeletions cause infertility have been well described; however, the therapeutic targets remain a challenge. Here, we used whole-genome sequencing to explore the mechanism of Y chromosome deletion and potential therapeutic targets in a patient with infertility. There were no abnormalities in the patient’s medical history. Routine semen analysis showed immotile sperm and only two motile spermatozoa were occasionally see after centrifugation, indicating that the direct cause of infertility was an abnormal sperm count and motility. A Y chromosome microdeletion test revealed partial deletion of the AZFcregion, including AZFc1, AZFc2, AZFc3, and AZFc4. Whole-genome sequencing showed that the patient had seven harmful mutations, with only one significant epigenetic mutation, SH3KBP1. Gene Ontology analysis of these meaningful mutations indicated involvement of cAMP signaling pathways. The patient’s wife became pregnant following in vitrofertilization, and no significant abnormalities were found during prenatal examination. This case suggests that Y chromosome microdeletion and gene mutation may affect the cAMP signaling pathway, leading to reduced sperm quality and male infertility.