A study of 10 Rotating Radio Transients using Parkes radio telescope

Rotating Radio Transients (RRATs) are a relatively new subclass of pulsars that emit detectable radio bursts sporadically. We conducted an analysis of 10 RRATs observed using the Parkes telescope, with 8 of these observed via the Ultra-Wideband Receiver. We measured the burst rate and produced integrated profiles spanning multiple frequency bands for 3 RRATs. We also conducted a spectral analysis on both integrated pulses and individual pulses of 3 RRATs. All of their integrated pulses follow a simple power law, consistent with the known range of pulsar spectral indices. Their average spectral indices of single pulses are -0.9, -1.2, and -1.0 respectively, which are within the known range of pulsar spectral indices. Additionally, we find that the spreads of single-pulse spectral indices for these RRATs (ranging from -3.5 to +0.5) are narrower compared to what has been observed in other RRATs (Shapiro-Albert et al. 2018; Xie et al. 2022). It is notable that the average spectral index and scatter of single pulses are both relatively small. For the remaining 5 RRATs observed at the UWL receiver, we also provided the upper limits on fluence and flux density. In addition, we obtained the timing solution of PSR J1709-43. Our analysis shows that PSRs J1919+1745, J1709-43 and J1649-4653 are potentially nulling pulsars or weak pulsars with sparse strong pulses.Comment: 16 pages, 8 figures, RAA accepte

Discovery, preparation and identification of a new type of oxyphenisatine di（acetate） analogue in dietary supplement

Objective: To find, prepare and identify a new oxyphenisatine di（acetate） analogue. Methods: A suspected derivative of oxyphenisatine di（acetate） was found by high-performance liquid chromatography-quadrupole-time-of-flight-mass spectrometry during the routine screening of weight loss healthcare product. The compound was isolated and purified by column chromatography, and the possible structures were inferred from the information of isotope mass spectra, secondary ion mass spectra, one-dimensional and two-dimensional NMR spectra. Finally, all possible structures were prepared by de novo synthesis strategy, and their fine structures were confirmed by spectral comparison. Results： The compound was identified as 5-Cl oxyphenisatine di（acetate）, a new type of oxyphenisatine di（acetate）, which has not been approved as food additives. Conclusion: The toxicological and pharmacological effects of this compound are not clear and should be of concern to regulators. The mass spectrometric fragmentation rule and the de novo synthesis of doubtful structures of these compounds will be beneficial to confirm the fine structure of new compounds

Exploring how the ambidextrous leadership influences knowledge workers innovative behavior: a two stage SEM-ANN analysis

This study investigates the impact of ambidextrous leadership, which integrates transformational and transactional leadership styles, on the innovative behavior of knowledge workers. Grounded in theory of reciprocal determinism, it explores the mediating roles of perceived organizational support and self-efficacy, addressing gaps in the literature on leadership and innovation. Data were collected from 372 knowledge workers in China via an online survey, and analyzed using a two-stage methodology that combines Partial Least Squares Structural Equation Modeling (PLS-SEM) to assess linear relationships and Artificial Neural Network (ANN) analysis to capture non-linear dynamics. The results indicate that ambidextrous leadership significantly enhances knowledge workers' innovative behavior through the mediating effects of perceived organizational support and self-efficacy, with a chain mediation effect underscoring the interplay between leadership, organizational support, and individual psychology. By integrating ambidextrous leadership with reciprocal determinism theory, this study enriches the theoretical understanding of leadership's role in fostering innovation and provides cross-cultural evidence of its applicability. The findings offer practical strategies for organizations to foster innovation by creating supportive environments and adopting adaptive leadership practices. Future research could explore longitudinal effects and investigate additional mediating or moderating variables to further deepen the understanding of leadership's impact on innovation

The deregulation of arachidonic acid metabolism in ovarian cancer

Arachidonic acid (AA) is a crucial polyunsaturated fatty acid in the human body, metabolized through the pathways of COX, LOX, and cytochrome P450 oxidase to generate various metabolites. Recent studies have indicated that AA and its metabolites play significant regulatory roles in the onset and progression of ovarian cancer. This article examines the recent research advancements on the correlation between AA metabolites and ovarian cancer, both domestically and internationally, suggesting their potential use as biological markers for early diagnosis, targeted therapy, and prognosis monitoring

一种食用油锁养保鲜生产工艺

为了解决食用油在储存过程中因发生各种变化而造成的品质下降问题，介绍了一种食用油的锁养保鲜生产工艺，包括全工段恒温灌装、充氮灌装和抗紫外瓶包装。实践证明，全工段恒温灌装有效避免了灌装油温过高产生负压造成的瓶内缩吸瘪，减少了标签不平整情况的发生；充氮灌装使食用油包装瓶内顶空残氧量低于6％，产品残氧量指标稳定；以色母为抗紫外助剂，制成的食品级食用油包装瓶可防止紫外线对食用油品质的影响。采用此生产工艺，可以有效提高食用油的品质并延长储存期。 In order to solve the problem of degradation of the quality of edible oil due to various changes that occur during the storage process, a fresh-keeping production technology of edible oil was introduced, including constant temperature filling in the whole section, nitrogen filling and UV resistant bottle packaging. The practice showed that the constant temperature filling in the whole section could effectively avoid the bottle shrinkage caused by the high filling oil temperature and negative pressure, and reduce the occurrence of uneven labels. Nitrogen filling could make the residual oxygen content in the processed edible oil bottle less than 6%, and the product residual oxygen index stable. The food grade edible oil packaging bottle made of color masterbatch as an anti-ultraviolet additive could prevent the influence of ultraviolet rays on the quality of edible oil. The use of this production process can effectively improve the quality of edible oil and extend the storage period

Overview of Viral Pneumonia Associated With Influenza Virus, Respiratory Syncytial Virus, and Coronavirus, and Therapeutics Based on Natural Products of Medicinal Plants

Viral pneumonia has been a serious threat to global health, especially now we have dramatic challenges such as the COVID-19 pandemic. Approximately six million cases of community-acquired pneumonia occur every year, and over 20% of which need hospital admission. Influenza virus, respiratory virus, and coronavirus are the noteworthy causative agents to be investigated based on recent clinical research. Currently, anaphylactic reaction and inflammation induced by antiviral immunity can be incriminated as causative factors for clinicopathological symptoms of viral pneumonia. In this article, we illustrate the structure and related infection mechanisms of these viruses and the current status of antiviral therapies. Owing to a set of antiviral regiments with unsatisfactory clinical effects resulting from side effects, genetic mutation, and growing incidence of resistance, much attention has been paid on medicinal plants as a natural source of antiviral agents. Previous research mainly referred to herbal medicines and plant extracts with curative effects on viral infection models of influenza virus, respiratory virus, and coronavirus. This review summarizes the results of antiviral activities of various medicinal plants and their isolated substances, exclusively focusing on natural products for the treatment of the three types of pathogens that elicit pneumonia. Furthermore, we have introduced several useful screening tools to develop antiviral lead compounds

A C-X-C Chemokine Receptor Type 2–Dominated Cross-talk between Tumor Cells and Macrophages Drives Gastric Cancer Metastasis

Purpose: C-X-C chemokine receptor type 2 (CXCR2) is a key regulator that drives immune suppression and inflammation in tumor microenvironment. CXCR2-targeted therapy has shown promising results in several solid tumors. However, the underlying mechanism of CXCR2-mediated cross-talk between gastric cancer cells and macrophages still remains unclear. Experimental Design: The expression of CXCR2 and its ligands in 155 human gastric cancer tissues was analyzed via immunohistochemistry, and the correlations with clinical characteristics were evaluated. A coculture system was established, and functional assays, including ELISA, transwell, cell viability assay, and qPCR, were performed to determine the role of the CXCR2 signaling axis in promoting gastric cancer growth and metastasis. A xenograft gastric cancer model and a lymph node metastasis model were established to study the function of CXCR2 in vivo. Results: CXCR2 expression is associated with the prognosis of patients with gastric cancer (P = 0.002). Of all the CXCR2 ligands, CXCL1 and CXCL5 can significantly promote migration of gastric cancer cells. Macrophages are the major sources of CXCL1 and CXCL5 in the gastric cancer microenvironment, and promote migration of gastric cancer cells through activating a CXCR2/STAT3 feed-forward loop. Gastric cancer cells secrete TNF-α to induce release of CXCL1 and CXCL5 from macrophages. Inhibiting CXCR2 pathway of gastric cancer cells can suppress migration and metastasis of gastric cancer in vitro and in vivo. Conclusions: Our study suggested a previously uncharacterized mechanism through which gastric cancer cells interact with macrophages to promote tumor growth and metastasis, suggesting that CXCR2 may serve as a promising therapeutic target to treat gastric cancer

High-bandwidth perovskite photonic sources on silicon

Light-emitting diodes (LEDs) are ubiquitous in modern society, with applications spanning from lighting and displays to medical diagnostics and data communications. Metal-halide perovskites are promising materials for LEDs because of their excellent optoelectronic properties and solution processability. Although research has progressed substantially in optimizing their external quantum efficiency, the modulation characteristics of perovskite LEDs remain unclear. Here we report a holistic approach for realizing fast perovskite photonic sources on silicon based on tailoring alkylammonium cations in perovskite systems. We reveal the recombination behaviour of charged species at various carrier density regimes relevant for their modulation performance. By integrating a Fabry–Pérot microcavity on silicon, we demonstrate perovskite devices with efficient light outcoupling. We achieve device modulation bandwidths of up to 42.6 MHz and data rates above 50 Mbps, with further analysis suggesting that the bandwidth may exceed gigahertz levels. The principles developed here will support the development of perovskite light sources for next-generation data-communication architectures. The demonstration of solution-processed perovskite emitters on silicon substrates also opens up the possibility of integration with micro-electronics platforms

Precessing jet nozzle connecting to a spinning black hole in M87

The nearby radio galaxy M87 offers a unique opportunity to explore the connections between the central supermassive black hole and relativistic jets. Previous studies of the inner region of M87 revealed a wide opening angle for the jet originating near the black hole. The Event Horizon Telescope resolved the central radio source and found an asymmetric ring structure consistent with expectations from General Relativity. With a baseline of 17 years of observations, there was a shift in the jet's transverse position, possibly arising from an eight to ten-year quasi-periodicity. However, the origin of this sideways shift remains unclear. Here we report an analysis of radio observations over 22 years that suggests a period of about 11 years in the position angle variation of the jet. We infer that we are seeing a spinning black hole that induces the Lense-Thirring precession of a misaligned accretion disk. Similar jet precession may commonly occur in other active galactic nuclei but has been challenging to detect owing to the small magnitude and long period of the variation.Comment: 41 pages, 7 figures, 7 table