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Aim： To investigate the neuroprotective effects of morin on 1-methyt-4-phenylpyridinium ion （MPP＋）-induced apoptosis in neuronal dif- ferentiated PC12 cells as well as in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine （MPTP） mouse model of Parkinson disease （PD）. Methods： PC12 cells were challenged with MPP in the presence or absence of morin. Cell viability was determined using MTT assay. Cell apoptosis was measured using flow cytometry. Generation of reactive oxygen species （ROS） was assayed using fluorescence assay. In an MPTP mouse model of PD, behavioral deficits, striatal dopamine content, and number of dopaminergic neurons were measured. Results： MPP~ induced apoptosis and ROS formation in PC12 cells. Concomitant treatment with morin （5-50 IJmol/L） significantly attenuated the loss of cell viability and apoptosis when compared with MPP~ treatment alone. Morin also attenuated ROS formation induced by MPP . MPTP induced permanent behavioral deficits and nigrostriatal lesions in mice. When administered prior to MPTP, morin （20 to 100 mg/kg） attenuated behavioral deficits, dopaminergic neuronal death and striatal dopamine depletion in the MPTP mouse model. Conclusion： The findings suggest that morin has neuroprotective actions both in vitro and in vivo, and may provide a novel therapeutic agent for the treatment of PD and other neurodegenerative diseases.

Polarization measurements of fast radio bursts (FRBs) probe the magnetized plasma surrounding their central engines. FRB~20240114A is an exceptionally active repeating source, with 17,356 bursts detected between 2024 January 28 and 2025 May 30 by FAST, enabling time-resolved polarimetric studies. In this work, we present a polarimetric catalog of 6,131 bright bursts (with a signal-to-noise ratio S/N \\(\\) 20, 35.3% of the total sample), including arrival time (MJD\\(_topo\\)), dispersion measure (DM), burst width (W\\(_eff\\)), bandwidth, Faraday rotation measure (RM), linear and circular polarization degrees (DOL, DOC), and intrinsic polarization angle (PA\\(_0\\)). We detect a clear temporal evolution of RM: after an initial stable phase, it decreases linearly by \\(\\)200 \\( rad\\ m^-2\\) over 200 days, forming a bimodal distribution, whereas DM remains stable at 528.9 \\( pc\\ cm^-3\\). The linear polarization fraction is generally high, with the 3\\(\\) lower bound around 76%, while circular polarization is low, with 1,157 of 17,356 bursts (6.67%) having DOC \\(\\)10%. We perform a power-law fit between \\(|V|\\)/I and \\(|RM|\\), which yields an index of \\(-2.98 0.80\\). It is found that the combined 2D distribution of L/I versus V/I remains stable, implying that the emission mechanism is largely invariant. Our PA\\(_0\\) measurements show a broad, non-uniform distribution, implying a complex emission geometry. These results suggest that FRB~20240114A resides in a dynamically evolving magneto-ionic environment. This catalog provides a foundation for studies of repeating FRB progenitors and their environments.

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 Object Monitor/Visible Telescope (SVOM/VT). The 13.08-hour 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 multi-epoch 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 \\( 10^39\\) \\( 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 non-repeating FRB, disfavoring ultra-luminous X-ray sources (ULXs) 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.

Polymer crosslinking imbues chemical stability to thin films at the expense of lower molecular transportation rates. Here in this work we deployed molecular dynamics simulations to optimise the selection of crosslinking compounds that overcome this trade-off relationship. We validated these simulations using a series of experiments and exploited this finding to underpin the development of a pervaporation (PV) desalination thin-film composite membrane with water fluxes reaching 234.9 ± 8.1 kg m −2 h −1 and salt rejection of 99.7 ± 0.2 %, outperforming existing membranes for pervaporation and membrane distillation. Key to achieving this state-of-the-art desalination performance is the spray coating of 0.73 μm thick crosslinked dense, hydrophilic polymers on to electrospun nanofiber mats. The desalination performances of our polymer nanocomposites are harnessed here in this work to produce freshwater from brackish water, seawater and brine solutions, addressing the key environmental issue of freshwater scarcity. Polymer crosslinking in desalination membranes adds stability on the cost of molecular transportation rates through the membrane. Here the authors tailor crosslinking of desalination membranes to overcome the stability and transport trade-off, and demonstrate a pervaporation desalination thin-film composite membrane with high water flux.

Regional severe haze represents an enormous environmental problem in China, influencing air quality, human health, ecosystem, weather, and climate. These extremes are characterized by exceedingly high concentrations of fine particulate matter (smaller than 2.5 μm, or PM2.5) and occur with extensive temporal (on a daily, weekly, to monthly timescale) and spatial (over a million square kilometers) coverage. Although significant advances have been made in field measurements, model simulations, and laboratory experiments for fine PM over recent years, the causes for severe haze formation have not yet to be systematically/comprehensively evaluated. This review provides a synthetic synopsis of recent advances in understanding the fundamental mechanisms of severe haze formation in northern China, focusing on emission sources, chemical formation and transformation, and meteorological and climatic conditions. In particular, we highlight the synergetic effects from the interactions between anthropogenic emissions and atmospheric processes. Current challenges and future research directions to improve the understanding of severe haze pollution as well as plausible regulatory implications on a scientific basis are also discussed.

Background Dysfunctions of long non-coding RNA (lncRNAs) have been associated with the initiation and progression of hepatocellular carcinoma (HCC), but the clinicopathologic significance and potential role of lncRNA PTTG3P (pituitary tumor-transforming 3, pseudogene) in HCC remains largely unknown. Methods We compared the expression profiles of lncRNAs in 3 HCC tumor tissues and adjacent non-tumor tissues by microarrays. In situ hybridization (ISH) and quantitative real-time polymerase chain reaction (qRT-PCR) were applied to assess the level of PTTG3P and prognostic values of PTTG3P were assayed in two HCC cohorts ( n  = 46 and 90). Artificial modulation of PTTG3P (down- and over-expression) was performed to explore the role of PTTG3P in tumor growth and metastasis in vitro and in vivo. Involvement of PTTG1 (pituitary tumor-transforming 1), PI3K/AKT signaling and its downstream signals were validated by qRT-PCR and western blot. Results We found that PTTG3P was frequently up-regulated in HCC and its level was positively correlated to tumor size, TNM stage and poor survival of patients with HCC. Enforced expression of PTTG3P significantly promoted cell proliferation, migration, and invasion in vitro, as well as tumorigenesis and metastasis in vivo. Conversely, PTTG3P knockdown had opposite effects. Mechanistically, over-expression of PTTG3P up-regulated PTTG1, activated PI3K/AKT signaling and its downstream signals including cell cycle progression, cell apoptosis and epithelial-mesenchymal transition (EMT)-associated genes. Conclusions Our findings suggest that PTTG3P, a valuable marker of HCC prognosis, promotes tumor growth and metastasis via up-regulating PTTG1 and activating PI3K/AKT signaling in HCC and might represent a potential target for gene-based therapy.

In recent years, severe haze events often occurred in China, causing serious environmental problems. The mechanisms responsible for the haze formation, however, are still not well understood, hindering the forecast and mitigation of haze pollution. Our study of the 2012–13 winter haze events in Beijing shows that atmospheric water vapour plays a critical role in enhancing the heavy haze events. Under weak solar radiation and stagnant moist meteorological conditions in winter, air pollutants and water vapour accumulate in a shallow planetary boundary layer (PBL). A positive feedback cycle is triggered resulting in the formation of heavy haze: (1) the dispersal of water vapour is constrained by the shallow PBL, leading to an increase in relative humidity (RH); (2) the high RH induces an increase of aerosol particle size by enhanced hygroscopic growth and multiphase reactions to increase particle size and mass, which results in (3) further dimming and decrease of PBL height, and thus further depressing of aerosol and water vapour in a very shallow PBL. This positive feedback constitutes a self-amplification mechanism in which water vapour leads to a trapping and massive increase of particulate matter in the near-surface air to which people are exposed with severe health hazards.

Amine-containing particles were characterized in an urban area of Chongqing during both summer and winter using a single-particle aerosol mass spectrometer (SPAMS). Among the collected particles, 12.7 % were amine-containing in winter and 8.3 % in summer. Amines were internally mixed with elemental carbon (EC), organic carbon (OC), sulfate, and nitrate. Diethylamine (DEA) was the most abundant among amine-containing particles. Wintertime amine-containing particles were mainly from the northwest direction where a forest park was located; in summer, they were from the northwest and southwest (traffic hub) directions. These origins suggest that vegetation and traffic were the primary sources of particulate amines. The average relative peak area of DEA depended strongly on humidity, indicating that the enhancement of DEA was possibly due to increasing aerosol water content and aerosol acidity. Using an adaptive resonance theory neural network (ART-2a) algorithm, four major types of amine-containing particles were clustered: amine–organic carbon (A-OC), A-OCEC, DEA-OC, and A-OCEC aged. The identified particle types implied that amines were taken up by particles produced from traffic and biomass burning. The knowledge gained in this study is useful to understand the atmospheric processing, origin, and sources of amine-containing particles in the urban area of Chongqing.

Investigation of the chemical nature and sources of particulate matter at urban locations in four Chinese cities during a severe haze pollution event finds that the event was driven to a large extent by secondary aerosol formation. What caused China's atmospheric haze? Air pollution is an important environmental problem in China, but the factors contributing to the high levels of particulate matter present during haze pollution events remain poorly understood. This paper investigates the chemical nature and sources of particulate matter at urban locations in four Chinese cities during the severe haze pollution event of January 2013, and finds that the event was driven to a large extent by secondary aerosol formation. This indicates that mitigation strategies focused on primary particulate emissions alone are unlikely to be fully effective. Additional measures such as controlling emissions of volatile organic compounds from fossil fuel combustion (mostly coal and traffic) and biomass burning may be required if China's particulate pollution is to be reduced. Rapid industrialization and urbanization in developing countries has led to an increase in air pollution, along a similar trajectory to that previously experienced by the developed nations 1 . In China, particulate pollution is a serious environmental problem that is influencing air quality, regional and global climates, and human health 2 , 3 . In response to the extremely severe and persistent haze pollution experienced by about 800 million people during the first quarter of 2013 (refs 4 , 5 ), the Chinese State Council announced its aim to reduce concentrations of PM 2.5 (particulate matter with an aerodynamic diameter less than 2.5 micrometres) by up to 25 per cent relative to 2012 levels by 2017 (ref. 6 ). Such efforts however require elucidation of the factors governing the abundance and composition of PM 2.5 , which remain poorly constrained in China 3 , 7 , 8 . Here we combine a comprehensive set of novel and state-of-the-art offline analytical approaches and statistical techniques to investigate the chemical nature and sources of particulate matter at urban locations in Beijing, Shanghai, Guangzhou and Xi’an during January 2013. We find that the severe haze pollution event was driven to a large extent by secondary aerosol formation, which contributed 30–77 per cent and 44–71 per cent (average for all four cities) of PM 2.5 and of organic aerosol, respectively. On average, the contribution of secondary organic aerosol (SOA) and secondary inorganic aerosol (SIA) are found to be of similar importance (SOA/SIA ratios range from 0.6 to 1.4). Our results suggest that, in addition to mitigating primary particulate emissions, reducing the emissions of secondary aerosol precursors from, for example, fossil fuel combustion and biomass burning is likely to be important for controlling China’s PM 2.5 levels and for reducing the environmental, economic and health impacts resulting from particulate pollution.

Background Cotton ( Gossypium spp.) is the most important world-wide fiber crop but salt stress limits cotton production in coastal and other areas. Growth regulation factors (GRFs) play regulatory roles in response to salt stress, but their roles have not been studied in cotton under salt stress. Results We identified 19 GRF genes in G. raimondii , 18 in G. arboreum , 34 in G. hirsutum and 45 in G. barbadense , respectively. These GRF genes were phylogenetically analyzed leading to the recognition of seven GRF clades. GRF genes from diploid cottons ( G. raimondii and G. arboreum ) were largely retained in allopolyploid cotton, with subsequent gene expansion in G. barbadense relative to G. hirsutum . Most G. hirsutum GRF ( GhGRF ) genes are preferentially expressed in young and growing tissues. To explore their possible role in salt stress, we used qRT-PCR to study expression responses to NaCl treatment, showing that five GhGRF genes were down-regulated in leaves. RNA-seq experiments showed that seven GhGRF genes exhibited decreased expression in leaves under NaCl treatment, three of which ( GhGRF3 , GhGRF4 , and GhGRF16 ) were identified by both RNA-seq and qRT-PCR. We also identified six and three GRF genes that exhibit decreased expression under salt stress in G. arboreum and G. barbadense , respectively. Consistent with its lack of leaf withering or yellowing under the salt treatment conditions, G. arboreum had better salt tolerance than G. hirsutum and G. barbadense . Our results suggest that GRF genes are involved in salt stress responses in Gossypium . Conclusion In summary, we identified candidate GRF genes that were involved in salt stress responses in cotton.