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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

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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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Existence and asymptotics of normalized solutions for the logarithmic Schr?dinger system

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Science China Mathematics 2024年第9期67卷 2019-2048页

作者： Qian Zhang Wenming Zou department of Mathematical sciences Tsinghua University

This paper is concerned with the following logarithmic Schr?dinger system:■where Ω=RNor Ω?RN（N≥3） is a bounded smooth domain,and ωi∈R,μi,ρi> 0 for i=1,***,p,q≥1,and 2≤p+q≤2*,where 2*:=2N/N-2. By using a Gagliardo-Nirenberg inequality and a careful estimation of u log u2,firstly,we provide a unified proof of the existence of the normalized ground state solution for all 2≤p+q ≤2*.Secondly,we consider the stability of normalized ground state ***,we analyze the behavior of solutions for the Sobolev-subcritical case and pass to the limit as the exponent p+q approaches 2*.Notably,the uncertainty of the sign of u log u2in（0,+∞） is one of the difficulties of this paper,and also one of the motivations we are interested *** particular,we can establish the existence of positive normalized ground state solutions for the Brézis-Nirenberg type problem with logarithmic perturbations（i.e.,p+q=2*）.In addition,our study includes proving the existence of solutions to the logarithmic type Bréis-Nirenberg problem with and without the *** ∫Ω|ui|2dx=ρi（i=1,2） by two different methods,*** results seem to be the first result of the normalized solution of the coupled nonlinear Schr?dinger system with logarithmic perturbations.

关键词： logarithmic Schrödinger system Brézis-Nirenberg problem normalized solution existence and stability behavior of solutions

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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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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

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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

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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

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Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： S.W.Wi Y.S.Lee department of Physics and Integrative Institute of Basic sciences Soongsil University

We investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of Li+is found to increase the Eu3+emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of Li + Photoluminescence Sensitizer Rare earths

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Impact of tourism on the vigilance behavior of the Cyprus rock agama(Laudakia cypriaca)

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Integrative Zoology 2024年第3期19卷 577-583页

作者： Artur GOLAWSKI Iris CHARALAMBIDOU Sylwia GOLAWSKA Faculty of sciences Siedlce University of Natural Sciences and HumanitiesSiedlcePolandand department of Life sciences School of Life and Health SciencesUniversity of NicosiaNicosiaCyprus

Escape behavior is a common antipredator strategy among wild ***,we investigated the effect of four factors on the vigilance behavior of the endemic Cyprus rock agama(Laudakia cypriaca).Flight initiation distance(FID,the minimum distance to which an observer can approach a lizard before it flees)was measured in relation to the type of location(tourist *** area),the observer’s starting distance,air temperature,and substrate *** collected data for 39 agamas in tourist areas and 34 of these lizards in nontourist *** a whole,the mean starting distance was 10.5 m and the FID was 3.6 *** average substrate temperature was 34.0℃ and the average air temperature 29.6℃.Only the type of area affected the agamas’escape decisions with FID being 1.8 m shorter in tourist areas than in nontourist areas(2.7 m vs.4.5 m).This is probably due to the habituation of lizards to the presence of humans in the former *** study shows that tourism strongly affects the behavior of lizards,which may have consequences for the functioning of the *** can increase the safety of lizards by creating a human shield to deter *** the tourist season is over,lizards may become more vulnerable to predators.

关键词： anthropogenic disturbance flight initiation distance lizards tourism vigilance behavior

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Quantum correlations and entanglement in coupled optomechanical resonators with photon hopping via Gaussian interferometric power analysis

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Chinese Physics B 2024年第5期33卷 204-211页

作者： Y.Lahlou B.Maroufi M.Daoud LPHE-MS Department of PhysicsFaculty of SciencesMohammed V UniversityRabatMorocco LPMS Department of PhysicsFaculty of SciencesIbn Tofail UniversityKénitraMorocco

Quantum correlations that surpass entanglement are of great importance in the realms of quantum information processing and quantum ***,for quantum systems prepared in pure states,it is difficult to differentiate between quantum entanglement and quantum ***,this indistinguishability is no longer holds for mixed *** contribute to a better understanding of this differentiation,we have explored a simple model for both generating and measuring these quantum *** study concerns two macroscopic mechanical resonators placed in separate Fabry–Pérot cavities,coupled through the photon hopping *** system offers a comprehensively way to investigate and quantify quantum correlations beyond entanglement between these mechanical *** key ingredient in analyzing quantum correlation in this system is the global covariance *** forms the basis for computing two essential metrics:the logarithmic negativity(E_(N)^(m))and the Gaussian interferometric power(P_(G)^(m)).These metrics provide the tools to measure the degree of quantum entanglement and quantum correlations,*** study reveals that the Gaussian interferometric power(P_(G)^(m))proves to be a more suitable metric for characterizing quantum correlations among the mechanical modes in an optomechanical quantum system,particularly in scenarios featuring resilient photon hopping.

关键词： quantum correlations entanglement Gaussian interferometric power logarithmic negativity optomechanics photon hopping

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