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Assessment of phytochemicals, antioxidant, anti-hemolytic, anti-inflammatory and anti-cancer potential of flowers, leaves and stem extracts of Rosa arvensis

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Journal of Traditional Chinese Medicine 2024年第4期44卷 804-812页

作者： Zubaria Tul Ain Iram Fatima Sana Naseer Sobia Kanwal Tariq Mahmood department of Plant sciences Quaid-i-Azam University department of Biology Allama Iqbal Open University department of Plant sciences Faculty of Biological SciencesQuaid-i-Azam University Pakistan Academy of sciences

OBJECTIVE: To evaluate phytochemicals and in vitro biological potential of flowers, leaves and stem extracts of Rosa arvensis. METHODS: Presence of twenty secondary metabolites was confirmed and then phenolic and flavonoid contents were quantified spectrophotometrically. Fourier Transform Infrared spectroscopy was conducted to ascertain functional groups and antioxidant potential was examined using 2,2-diphenyl-1-picrylhydrazyl scavenging activity, total antioxidant capacity and total reducing power *** erythrocytes were used to assess anti-hemolytic activity and five bacterial strains were examined to determine antibacterial potential of plant extracts. Radish seeds were used to perform phytotoxic activity and cytotoxic potential was evaluated via brine shrimps and PC3 cell lines. RESULTS: Highest phenolic contents were detected in the methanolic extract of Rosa arvensis flower（RAFM） [（151.635 ± 0.005） gallic acid equivalent mg/g] and highest flavonoid contents in the chloroform leaf extract（RALC） [（108.228 ± 0.004） quercetin equivalent mg/g]. Fourier-transform infrared spectroscopy analysis showed the presence of wide range of functional groups. The antioxidant assays indicated highest DPPH scavenging activity [IC50（23.5 ± 0.6） μg/mL] in the methanolic stem extract（RASM）, highest total antioxidant capacity [（265.1 ± 0.9） μg/mL] in RAFM and highest reducing potential [（209.9 ± 0.6） μg/mL] in leaf extract（RALM）. Highest antihemolytic activity [（90.0 ± 0.5） μg/mL] was recorded in RAFM and brine shrimp cytotoxicity potential [（52.3 ± 0.3） μg/mL] in RASM. The antimicrobial activity was detected highest [（21.1 ± 0.5） mm inhibition zones] in RALM against Streptococcus aureus. In the end, antiinflammatory and anti-cancer activity results depicted less than 50 % inhibition in the methanolic extracts. CONCLUSIONS: Our findings will be helpful in designing pharmaceutical regimens and therefore, more studies can be recommended to isolate and characterize compounds as

关键词： PC-3 cells anti-inflammatory agents hemolysis oxidative stress spectroscopy, fourier transform infrared

Global weirding at mass extinction horizons

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National Science Review 2024年第1期11卷 10-12页

作者： Gregory J.Retallack department of Earth sciences University of Oregon

A strong motivation for studying mass extinctions is understanding how current climatic and biodiversity crises will affect creatures living on land such as ourselves. Perhaps the question is: how bad can it get? In that case, terrestrial Permian-Triassic mass extinctions are an irresistible worst-case scenario [1].

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Analysis of ancient mass extinction recoveries in marine environments: generating strategies for managing outcomes of the current mass extinction

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National Science Review 2024年第1期11卷 8-10页

作者： David J.Bottjer department of Earth sciences University of Southern California

The defining feature of a mass extinction and its associated recovery is the global amount of extinction that occurred[1]. However, there is finer-scale detail to the story, as seen in the ongoing modern mass extinction(the sixth mass extinction), which exhibits variable effects among marine ecosystems and environments, and hence geographic areas [1].

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Host-guest cocrystals boost thermally activated delayed fluorescence materials

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Science China Chemistry 2024年第10期67卷 3179-3180页

作者： Wenzhi Yang Jiong Zhou department of Chemistry College of SciencesNortheastern University

Organic light-emitting diodes(OLEDs) play an important role in organic display and lighting fields. Thermally activated delayed fluorescence(TADF) materials have shown great potential in the OLED field because they can theoretically achieve 100% utilization of excitons and avoid heavy metal pollution problems [1].

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Late Ordovician Mass Extinction: Earth, fire and ice

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National Science Review 2024年第1期11卷 51-65页

作者： David A.T.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

The Late Ordovician Mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. Two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. These symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOME paleoecology palaeobiogeography biotas

New findings on the influence of El Nino events on tropical cyclone formation

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Science China Earth sciences 2024年第3期67卷 892-893页

作者： Liguang WU department of Atmospheric and Oceanic sciences Institute of Atmospheric SciencesFudan UniversityShanghai 200438China

Tropical cyclones typically form over warm tropical and subtropical ocean surfaces, as their formation and intensification rely primarily on the energy provided by the ocean. Pioneering research by Gray (1968) revealed that the formation of tropical cyclones requires the sea surface temperature (SST) to be no less than 26.5℃. Consequently, SST is commonly recognized as a crucial parameter among the environmental factors influencing tropical cyclone formation(Gray, 1979;Emanuel and Nolan, 2004).

关键词： tropical cyclone ocean

A fringe jump counting method for the phase measurement in the HCN laser interferometer on EAST and its FPGA-based implementation

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Plasma Science and Technology 2024年第4期26卷 156-161页

作者：姚远杨曜提昂宋扬张家敏王琰张耀刘海庆揭银先 Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People’s Republic of China Anhui Electrical Engineering Professional technique College Hefei 230022People’s Republic of China Institutes of Physical Science and Information Technology Anhui UniversityHefei 230601People’s Republic of China

Electron density in fusion plasma is usually diagnosed using laser-aided interferometers. The phase difference signal obtained after phase demodulation is wrapped, which is also called a fringe jump. A method has been developed to unwrap the phase difference signal in real time using FPGA, specifically designed to handle fringe jumps in the hydrogen cyanide(HCN) laser interferometer on the EAST superconducting tokamak. This method is designed for a phase demodulator using the fast Fourier transform(FFT) method at the front end. The method is better adapted for hardware implementation compared to complex mathematical analysis algorithms, such as field programmable gate array(FPGA). It has been applied to process the phase measurement results of the HCN laser interferometer on EAST in real time. Electron density results show good confidence in the fringe jump unwrapping method. Further possible application in other laser interferometers, such as the POlarimeter-INTerferometer(POINT)system on EAST tokamak is also discussed.

关键词： electron density laser-aided interferometer fringe jump unwrapping FPGA EAST

Non-thermal atmospheric-pressure positive pulsating corona discharge in degradation of textile dye Reactive Blue 19 enhanced by Bi_(2)O_(3) catalyst

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Plasma Science and Technology 2024年第2期26卷 104-113页

作者： Milica PETROVIC Dragan RADIVOJEVIC Sasa RANCEV Nena VELINOV Milos KOSTIC Danijela BOJIC Aleksandar BOJIC department of Chemistry Faculty of Sciences and MathematicsUniversity of NisNis 18000Serbia department of Physics Faculty of Sciences and MathematicsUniversity of NisNis 18000Serbia

In this work,monoclinic Bi_(2)O_(3) was applied for the first time,to the best of our knowledge,as a catalyst in the process of dye degradation by a non-thermal atmospheric-pressure positive pulsating corona *** research focused on the interaction of the plasma-generated species and the catalyst,as well as the role of the catalyst in the degradation *** decomposition of the anthraquinone reactive dye Reactive Blue 19(RB 19) was performed in a selfmade reactor ***_(2)O_(3) was prepared by electrodeposition followed by thermal treatment,and characterized by x-ray diffraction,scanning electron microscopy and energy-dispersive xray *** was observed that the catalyst promoted decomposition of plasma-generated H_(2)O_(2) into ·OH radicals,the principal dye-degrading reagent,which further attacked the dye *** catalyst improved the decolorization rate by 2.5 times,the energy yield by 93.4%and total organic carbon removal by 7.1%.Excitation of the catalyst mostly occurred through strikes by plasma-generated reactive ions and radical species from the air,accelerated by the electric field,as well as by fast electrons with an energy of up to 15 eV generated by the streamers reaching the liquid *** strikes transferred the energy to the catalyst and created the electrons and holes,which further reacted with H_(2)O_(2) and water,producing ·OH *** was indentified as the primary role of the catalyst in this *** reactions followed pseudo first-order *** of H_(2)O_(2) and the dye degradation rate increased with increase in the input *** optimal catalyst dose was 500 mg·dm^(-3).The decolorization rate was a little lower in river water compared with that in deionized water due to the side reactions of ·OH radicals with organic matter and inorganic ions dissolved in the river water.

关键词： corona RB 19 Bi_(2)O_(3) catalyst degradation

Raindrop Size Distributions in the Zhengzhou Extreme Rainfall Event on 20 July 2021:Temporal-Spatial Variability and Implications for Radar QPE

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Journal of Meteorological Research 2024年第3期38卷 489-503页

作者： Liman CUI Haoran LI Aifang SU Yang ZHANG Xiaona LYU Le XI Yuanmeng ZHANG Henan Key Laboratory of Agrometeorological Support and Applied technique China Meteorological AdministrationZhengzhou450003China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing100081China Henan Meteorological Observatory Zhengzhou450003China

In this study,a regional Parsivel OTT disdrometer network covering urban Zhengzhou and adjacent areas is employed to investigate the temporal-spatial variability of raindrop size distributions(DSDs)in the Zhengzhou extreme rainfall event on 20 July *** rain rates observed by disdrometers and rain gauges from six operational sites are in good agreement,despite significant site-to-site variations of 24-h accumulated rainfall ranging from 198.3 to 624.1 *** Parsivel OTT observations show prominent temporal-spatial variations of DSDs,and the most drastic change was registered at Zhengzhou Station where the record-breaking hourly rainfall of 201.9 mm over 1500-1600 LST(local standard time)was *** hourly rainfall is characterized by fairly high concentrations of large raindrops,and the mass-weighted raindrop diameter generally increases with the rain rate before reaching the equilibrium state of DSDs with the rain rate of about 50 mm h^(−1).Besides,polarimetric radar observations show the highest differential phase shift(K_(dp))and differential reflectivity(Z_(dr))near surface over Zhengzhou Station from 1500 to 1600 *** light of the remarkable temporal-spatial variability of DSDs,a reflectivity-grouped fitting approach is proposed to optimize the reflectivity-rain rate(Z-R)parameterization for radar quantitative precipitation estimation(QPE),and the rain gauge measurements are used for *** results show an increase of mean bias ratio from 0.57 to 0.79 and a decrease of root-mean-square error from 23.69 to 18.36 for the rainfall intensity above 20.0 mm h^(−1),as compared with the fixed Z-R *** study reveals the drastic temporal-spatial variations of rain microphysics during the Zhengzhou extreme rainfall event and warrants the promise of using reflectivity-grouped fitting Z-R relationships for radar QPE of such events.

关键词： extreme rainfall raindrop size distribution radar quantitative precipitation estimation(QPE)