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Aerosols influence cloud microphysical properties by acting as cloud condensation nuclei and ice nuclei. Aerosols have the potential to modify the location and intensity of precipitation by changing cloud properties. However, identifying precipitation changes induced by aerosols remains a significant challenge for current research. Dust aerosol carried by dust storms is an important source of ice nuclei. China and Mongolia are the primary desert regions in Asia and the world. The Mongolian cyclone in northern China is one of the significant weather systems that cause sandstorms in both countries. Studying the impact of dust aerosols on clouds under the weather conditions of Mongolian cyclones and sandstorms is of great significance. Due to challenges of aerial observations during dust storms, the impact of dust aerosols on clouds is minimally understood during Mongolian cyclone dust storms. In order to investigate the impact of dust aerosols on clouds, a study is conducted based on the comprehensive observation experiment of clouds in Beijing Area carried out by Beijing Weather Modification Center. An extremely rare case of strong sandstorm weather caused by a Mongolian cyclone and cold front is observed on 24 April 2009. The vertical macro and micro physical structure characteristics of dust cloud and clean cloud are compared and analyzed, and the potential influence of dust aerosols on clouds is discussed. Results show that dust aerosol transferred from China-Mongolia areas is an important source of ice nuclei in North China. It can be transferred vertically to a height of 3200 meters above the cloud top. The concentration of ice nuclei in the dust background area is significantly increased by 10 times compared to that in the clean background area. This increase further affects the microphysical structure of cumulus and stratocumulus clouds with high cloud top temperatures (-6 ℃ to -3 ℃) by altering the process of ice crystal formation. At the same temperature, the average concentration of ice crystals in the dust cloud increases significantly by nearly 10 times compared to that in the clean cloud. The liquid water content is reduced, leading to the formation of a large number of small ice crystal particles in the cloud. It inhibits the rime process and results in a significant reduction in the average concentration of precipitation particles compared to that in the clean cloud. Additionally, the spectral width of cloud droplets, ice and snow crystals, and precipitation particles is significantly narrower than that in the clean cloud. It will eventually weaken the precipitation, which will have a significant impact on the weather and climate in North China. It is helpful to enhance our understanding of the indirect effects of aerosols.

To better understand the influence of aerosols on micro-properties of clouds and to facilitate weather modification experiments including the analysis of various materials' seeding effect on clouds and precipitation, Beijing Weather Modification Center has taken a decisive step forward by constructing an advanced facility known as Beijing aerosol and cloud interaction chamber (BACIC) in suburban Pinggu district. Boasting an impressive volume of 70 m3, BACIC is not only the largest of its kind in operation in China, but also a testament to the scale of the country's commitment to this sphere of atmospheric science. The enormity of the chamber's capacity facilitates the performance of a broad spectrum of investigations, thus enhancing the comprehensiveness and reliability of the results obtained.Inside BACIC, advanced instrumentation allows for the meticulous measurement and control of temperature, relative humidity, and background aerosol concentration. During 2019-2021, the chamber's capabilities extend further, as demonstrated by successful tests of its ability to create liquid and mixed-phase clouds. These attributes, combined with its capacity to control the cloud droplet size distribution as proved by comparative experiments involving changes in expansion rate and aerosol number concentration, solidify BACIC's standing as a prime location for warm cloud experimentation. The chamber has also been utilized to investigate effects of anthropogenic pollution over North China Plain (NCP) on cloud microphysics. Using ambient air and manipulating the expansion rate, a significant correlation is discovered between such pollution and the size distribution of cloud droplets. Interestingly, while an increase in aerosol leads to higher number of cloud droplets, it also causes a decrease in droplet size, typically within the range of 5-8 μm. Furthermore, an increase in aerosol number concentration leads to a decrease in the activation rate of aerosols into cloud droplets. This activation rate is around 10% for aerosol concentrations less than 5000 cm-3, and remains stable even when the aerosol concentration increases to 10000 cm-3.BACIC is also proved useful in conducting warm cloud expansion experiments involving different hygroscopic materials. It shows that the distribution of submicron (less than 1 μm) hygroscopic catalysts in a polluted environment leads to narrowing of the cloud droplet spectrum. It suggests that for the purpose of artificially reducing warm clouds or fog, it is recommended to use larger particle sizes. The results obtained from these diverse series of experiments have significantly contributed to theoretical knowledge and provide practical guidance for the ongoing development of artificial weather modification techniques.

The vertical evolution of aerosol physiochemical properties significantly influence the capacity of particle water uptake at different atmospheric levels, which are important for the estimation of direct and indirect radiative impacts of aerosol. However, as one of the most important environmental parameters during the formation of cloud or fog, water vapor supersaturation cannot be directly measured. An aircraft observation was carried out on 13 November 2016 with stable stratiform clouds covering Beijing area. The results of aircraft in-situ measured aerosol particle size distribution, chemical composition, cloud droplet spectrum, and vertical distribution of aerosol physicochemical properties and activation ability near the cloud base are analyzed. The results show that Beijing area is under polluted conditions during the flight detection with the surface aerosol concentration (0.11-3 μm) of 4600 cm-3. The height range of cloud layer is 800-1200 m. The number concentration of aerosols at the cloud base is greatly lower compared with the surface, and the effective diameter significantly increases from 0.3 μm to 0.6 μm. Aerosol composition varies drastically with altitudes. The hydrophobic primary organic aerosol (POA) has a significant contribution at surface, but sharply decreases at the cloud base. Meanwhile, the fraction of inorganic species and secondary organic aerosol (SOA) increase significantly from surface to cloud base, resulting in hygroscopic parameter (κ) increasing from 0.25 (ground) to 0.32 (cloud base). The number concentration size spectrum of cloud droplets and aerosols in the cloud can be well connected, which could be deemed as activated and un-activated particles respectively. Meanwhile, the sum of their number concentrations is approximately equal to the total aerosol concentration below the cloud, indicating aerosol particles below the cloud base has a dominant contribution to the cloud droplet formation near the cloud base by activation. Thereby, the actual activation ratio of aerosol particles serves as cloud condensation nuclei (CCN) in the measured cloud can be obtained. Combining with in-situ measured aerosol size distribution, chemical composition, and calculated hygroscopic parameter below the cloud base, the aerosol activation ratio under different supersaturation ratio can be derived. Estimated through the comparison of calculated activation rate and the measurement, the mean supersaturation near this stratiform cloud base is about 0.048%. It implies that the aerosol characteristics at surface may not represent that at upper levels, where the evolution in vertical direction should be considered in evaluating the contribution of surface emissions to cloud particle nucleation and their atmospheric lifetime. This supersaturation estimating method is mainly based on conventional measurement of aerosol and droplets, which has a potential value for further application on cloud analysis.

This study aims to investigate the effects of different selenium (Se) sources on the growth performance of Chinese broilers and provide a scientific rationale for adding Se additives to broiler feed. Relevant studies that meet standard inclusion criteria were identified and extracted from China National Knowledge Infrastructure and Wanfang and Chinese Scientific Journal (VIP) databases. A total of 9 studies with 539 subjects were included. A meta-analysis was performed with STATA15.0 to estimate the combined standardized mean difference (SMD) with a 95% confidence interval (95% CI). Heterogeneity test of articles was examined by Q-test, and the results showed that P values of feed conversion ratio, average daily gain (ADG), and average daily intake were all less than 0.05, suggesting a strong heterogeneity among the selected literature. Therefore, the random effect model is selected to calculate the SMD of the three indexes. The combined SMDs (95% CI) of feed:gain, ADG, and average daily feed intake (ADFI) were −0.39 (−1.03, 0.25), 0.26 (−0.29, 0.81), and −1.45 (−3.09, 0.20), respectively, and the P values were all less than 0.05. This study shows that the absolute differences in the growth performance (feed:gain, ADG, and ADFI) of broilers fed with either organic or inorganic Se supplements at the same dose were quite small. The P values of Egger’s test were 0.770, 0.089, and 0.426, respectively, for the above indexes, showing no significant publication bias. Sensitivity analysis ensured the stability and reliability of the results. In summary, the effects of organic and inorganic Se in feed on the growth performance of broilers are statistically equal.

C58H56Cu2N6O2P2, monoclinic, P21/n, a = 12.0546(9) Å, b = 13.1669(10) Å, c = 16.7151(12) Å, β = 101.845(2)°, V = 2596.6(3) Å3, Z = 4, Rgt(F) = 0.0539, wRref(F2) = 0.1431, T = 293(2) K.

Breast cancer is the most common malignant tumour in women. Our research on alloimperatorin from Angelica dahurica showed that alloimperatorin inhibited breast cancer cell viability in a concentration-and time-dependent manner; it also showed that apoptosis and ferroptosis inhibitors significantly weakened the antisurvival effect of alloimperatorin. Alloimperatorin clearly induced breast cancer cell apoptosis and increased the activities of caspase-3, caspase-8, caspase-9, and poly (ADP-ribose) polymerase; it also caused significant mitochondrial shrinkage, promoted the accumulation of [Fe.sup.2+], reactive oxygen species, and malondialdehyde, and significantly reduced mRNA and protein expression levels of SLC7A11 and GPX4, indicating that alloimperatorin induces ferroptosis. In addition, alloimperatorin significantly promoted Kelch-like ECH-associated protein 1 (Keap1) expression; although it did not affect the expression of PGAM5 (mitochondrial serine/threonine protein phosphatase) and apoptosis-inducing factor mitochondria associated 1 (AIFM1), it significantly reduced the phosphorylation level of AIFM1. After downregulating the expression of Keap1, PGAM5, or AIFM1, the inhibitory effect of alloimperatorin on cell viability was significantly weakened, indicating that alloimperatorin regulates the Keap1/PGAM5/AIFM1 pathway to promote oxeiptosis. Alloimperatorin significantly inhibited the invasion of breast cancer cells, while Keap1 siRNA or GPX4 overexpression vectors significantly enhanced cell invasion and effectively reversed the anti-invasive effect of alloimperatorin. Therefore, alloimperatorin induces breast cancer cell apoptosis, ferroptosis, and oxeiptosis, thereby inhibiting cell growth and invasion. Key words: breast cancer, traditional Chinese medicine, alloimperatorin, ferroptosis, oxeiptosis Le cancer du sein est la tumeur maligne la plus fréquente chez les femmes. La recherche réalisée par les auteurs sur l'alloimpératorine d'Angelica dahurica a montré que l'alloimpératorine inhibait la viabilité des cellules du cancer du sein de manière dépendante de la concentration et du temps; elle a également montré que les inhibiteurs de l'apoptose et de la ferroptose affaiblissent significativement l'effet anti-survie de l'alloimpératorine. L'alloimpératorine induisait de manière évidente l'apoptose des cellules de cancer du sein et augmentait les activités de la caspase-3, de la caspase-8, de la caspase-9 et de la PARP; elle provoquait également une diminution importante du volume des mitochondries, favorisait l'accumulation de [Fe.sup.2+], d'ERO et de MDA, et réduisait de manière significative les niveaux d'expression de l'ARNm et des protéines SLC7A11 et de GPX4, ce qui indique que l'alloimpératorine induit la ferroptose. En outre, l'alloimpératorine favorisait significativement l'expression de Keap1; bien qu'elle n'ait pas affecté l'expression de PGAM5 et d'AIFM1, elle réduisait significativement le niveau de phosphorylation d'AIFM1. Après avoir régulé à la baisse l'expression de Keap1, PGAM5 ou AIFM1, l'effet inhibiteur de l'alloimpératorine sur la viabilité cellulaire était considérablement affaibli, ce qui indique que l'alloimpératorine régule la voie Keap1/PGAM5/AIFM1 pour promouvoir l'oxeiptose. L'alloimpératorine inhibait de manière significative l'invasion des cellules cancéreuses du sein, tandis qu'un ARNsi de Keap1 ou des vecteurs de surexpression de GPX4 augmentaient de manière significative l'invasion cellulaire et inversaient efficacement l'effet anti-invasif de l'alloimpératorine. Par conséquent, l'alloimpératorine induit l'apoptose, la ferroptose et l'oxeiptose des cellules du cancer du sein, inhibant ainsi la croissance et l'invasion cellulaires. [Traduit par la Rédaction] Mots-clés: cancer du sein, médecine traditionnelle chinoise, alloimpératorine, ferroptose, oxeiptose, Introduction Breast cancer is the most common malignant tumour in women worldwide and the leading cause of cancer-related death in women (Noor et al. 2021; Schick et al. 2021). Early [...]

Fine particulate matter (PM2.5) is closely linked to human health, with its sources generally divided into local emissions and regional transport. This study combined concentration-weighted trajectory (CWT) analysis with the HYSPLIT trajectory ensemble to obtain hourly-resolution pollutant source results. The Extreme Gradient Boosting (XGBoost) model was then employed to simulate local emissions and ambient PM2.5 in Beijing from 2013 to 2020. The results revealed that clean air masses influencing the Beijing area mainly originated from the north and east regions, exhibiting a strong winter and weak summer pattern. Following the implementation of the Air Pollution Prevention and Control Action Plan (Action Plan) by the Chinese government in 2017, pollution in Beijing decreased significantly, with the most substantial reduction in regional transport pollution events occurring in the west region during summer. Regional transport pollution events were most frequent in spring, up to 1.8 times higher than in winter. Pollutants mainly originated from the west and south regions, while polluted air masses from the east showed the least reduction, and the proportion of pollution sources from this region is gradually increasing. From 2013 to 2020, local emissions were the main contributors of pollution events in Beijing. The Action Plan has more effectively reduced pollution caused by regional transport, particularly during autumn and winter. This finding underscores the importance of Beijing prioritizing local emission reduction while also considering potential contributions from the east region to effectively mitigate pollution events. [ABSTRACT FROM AUTHOR]

Biological particles, as a fraction of organic particles, potentially play a crucial role in ice nucleation processes. However, the contributions and relationships of biological components and organic matter (OM) to atmospheric ice nucleation remain largely unexplored. Here, total ice nucleating particles (INPs), heat‐resistant INPs, lysozyme‐resistant INPs, nanoscale INPs (<0.22 μm), and heat‐resistant nanoscale INPs in precipitation collected at the summit of Mt. Lu, China, were determined using droplet freezing assays coupled with corresponding pretreatments. Heat‐sensitive INPs and lysozyme‐sensitive INPs were considered as biological INPs and bacterial INPs, respectively. Microorganisms and OM molecules in precipitation were identified by high‐throughput sequencing technology and ultrahigh‐resolution mass spectrometry, respectively. Results revealed a predominant biological (heat‐sensitive) composition (78.8% and 93.2%) of total and nanoscale INPs at temperatures above −15°C. Specifically, bacterial (lysozyme‐sensitive) INPs accounted for 36.1% of the biological INPs at temperatures above −15°C. A notable correlation between sulfur‐containing organic compounds, mainly proteinaceous and lignin‐like substances, and INPs was uncovered, with a co‐occurrence network linking these compounds to Gram‐positive bacteria and Agaricomycetes. This study underscored the possible significance of sulfur‐containing organic compounds in the ice nucleation capacity of biological INPs, further shedding light on the ice nucleation mechanisms and potential sources of biological INPs. Plain Language Summary: Ice nucleating particles (INPs) are particles that facilitate the freezing of water at temperatures above the homogenous freezing point, impacting cloud formation and precipitation processes in the atmosphere. This study identified different types of INPs, microbes, and organic matter in precipitation sampled from Mt. Lu in southeastern China and investigated the connections among them. The findings suggested that a significant portion of INPs were of biological origin. Sulfur‐containing organic compounds likely played an important role in ice nucleation, which may originate from certain microbial taxa. This study helps us understand the role of microbes and organic molecules in ice formation, which has broader implications in areas such as preserving biological materials at low temperatures or facilitating artificial snow production. Key Points: Biological materials predominated among the ice nucleating particles (INPs) identified in precipitationSulfur‐containing organic compounds, associated with specific microbial taxa, likely acted as efficient INPs in precipitationThis study provides a preliminary understanding of the connections among INPs, organic matter, and microorganisms [ABSTRACT FROM AUTHOR]

Traditional indoor positioning technologies mostly require advanced installation of hardware devices, resulting in high costs and long-term maintenance. With advancements in image recognition and deep learning technologies, indoor visual positioning based on image recognition has become increasingly mature. This method offers the benefits of low cost and does not require additional hardware installation. However, it still has inherent defects, such as cumbersome data collection, complex algorithms, and universality. To minimize indoor information pre-collection cost, improve versatility, and enable rapid deployment in low-performance mobile devices, this paper proposes a lightweight indoor positioning system based on multiple self-learning features and key frame classification. The system is divided into two stages: preprocessing and real-time positioning. In the preprocessing stage, image information is collected for the entire indoor environment, and a key-frame recognizer is trained based on the image information. Simultaneously, an environmental feature information database is established. In the real-time positioning stage, the system first uses mobile devices such as smartphones to obtain real-time video streams. A key frame recognizer based on convolutional neural networks identifies key frames in each video stream frame, thereby obtaining approximate positions for rough positioning. Second, feature points are identified in each frame of the video stream and matched with feature points with location information in the built environmental feature information database to calculate precise positions for fine positioning. It has significant optimizations compared with conventional visual solutions in terms of preprocessing data collection, algorithm performance consumption, and versatility. [ABSTRACT FROM AUTHOR]

Botrytis cinerea is a necrotrophic fungal plant pathogen that causes grey mould and rot diseases in many crops. Here, we show that the B. cinerea BcCrh4 transglycosylase is secreted during plant infection and induces plant cell death and pattern‐triggered immunity (PTI), fulfilling the characteristics of a cell death‐inducing protein (CDIP). The CDIP activity of BcCrh4 is independent of the transglycosylase enzymatic activity, it takes place in the apoplast and does not involve the receptor‐like kinases BAK1 and SOBIR1. During saprophytic growth, BcCrh4 is localized in the endoplasmic reticulum and in vacuoles, but during plant infection, it accumulates in infection cushions (ICs) and is then secreted to the apoplast. Two domains within the BcCrh4 protein determine the CDIP activities: a 20aa domain at the N′ end activates intense cell death and PTI, while a stretch of 52aa in the middle of the protein induces a weaker response and suppresses the activity of the 20aa N′ domain. Deletion of bccrh4 affected fungal development and IC formation in particular, resulting in reduced virulence. Collectively, our findings demonstrate that BcCrh4 is required for fungal development and pathogenicity, and hint at a dual mechanism that balances the virulence activity of this, and potentially other CDIPs. Summary statement: 1.The Botrytis cinerea transglycosylase BcCrh4 is an apoplastic effector with weak and hyperactive cell death‐inducing domains. The protein is recognized and activates the plant defence system, but the perception and signalling do not involve the receptor‐like kinases BAK1 and SOBIR1 complex.2.Two domains within the BcCrh4 protein determine activation of cell death and pattern‐triggered immunity: a 20‐amino‐acid domain located at the N′ end activates intense cell death and plant immunity, while a stretch of 52 amino acids located in the middle of the protein has a weak cell death‐inducing activity. The two domains probably compete on the same plant target hence the full‐length protein has a milder cell death and plant immunity‐inducing activity than that of the 20 amino acids domain alone. [ABSTRACT FROM AUTHOR]

Insoluble particles influence weather and climate by means of heterogeneous freezing process. Current weather and climate models face considerable uncertainties in freezing-process simulation due to limited information regarding species and number concentrations of heterogeneous ice-nucleating particles, particularly insoluble particles. Here, for the first time, the size distribution and species of insoluble particles are analyzed in 30 shells of 12 hailstones collected from China using scanning electron microscopy and energy-dispersive X-ray spectrometry. A total of 289 461 insoluble particles were detected and divided into three species – organics, dust, and bioprotein – utilizing machine learning methods. The size distribution of the insoluble particles of each species varies greatly among the different hailstones but little in their shells. Further, a classic size distribution of organics and dust followed logarithmic normal distributions, which could potentially be adapted in future weather and climate models despite the existence of uncertainties. Our findings highlight the need for atmospheric chemistry to be considered in the simulation of ice-freezing processes. [ABSTRACT FROM AUTHOR]