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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 UniversityIslamabad 45320Pakistan department of Biology Allama Iqbal Open UniversityIslamabad 04403Pakistan department of Plant Sciences Faculty of Biological SciencesQuaid-i-Azam UniversityIslamabad 45320Pakistan pakistan Academy of Sciences Islamabad 04403Pakistan

OBJECTIVE:To evaluate phytochemicals and in vitro biological potential of flowers,leaves and stem extracts of Rosa ***:Presence of twenty secondary metabolites was confirmed and then phenolic and flavonoid contents were quantified *** 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 *** seeds were used to perform phytotoxic activity and cytotoxic potential was evaluated via brine shrimps and PC3 cell ***: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 *** 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 *** antimicrobial activity was detected highest[(21.1±0.5)mm inhibition zones]in RALM against Streptococcus *** the end,antiinflammatory and anti-cancer activity results depicted less than 50%inhibition in the methanolic ***:Our findings will be helpful in designing pharmaceutical regimens and therefore,more studies can be recommended to isolate and characterize compounds associated with the biological activities of Rosa arvensis.

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

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Exploring changes of precipitation extremes under climate change through global variable-resolution modeling

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Science Bulletin 2024年第2期69卷 237-247页

作者： Wei Sun Jian Li Rucong Yu Nina Li Yi Zhang State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Institute of Tibetan Plateau Meteorology China Meteorological AdministrationChengdu 610072China department of Atmospheric Science Yunnan UniversityKunming 650091China National meteorological Center China Meteorological AdministrationBeijing 100081China 2035 Future Laboratory PIESAT Information Technology Co.Ltd.Beijing 100105China

Understanding the responses of precipitation extremes to global climate change remains limited owing to their poor representations in models and complicated interactions with multi-scale *** we take the record-breaking precipitation over China in 2021 as an example,and study its changes under three different climate scenarios through a developed pseudo-global-warming(PGW)experimental framework with 60-3 km variable-resolution global ensemble *** to the present climate,the precipitation extreme under a warmer(cooler)climate increased(decreased)in intensity,coverage,and total amount at a range of 24.3%-37.8%(18.7%-56.1%).With the help of the proposed PGW experimental framework,we further reveal the impacts of the multi-scale system interactions in climate change on the precipitation *** the warmer climate,large-scale water vapor transport converged from double typhoons and the subtropical high marched into central China,enhancing the convective energy and instability on the leading edge of the transport *** a result,the mesoscale convective system(Mcs)that directly contributed to the precipitation extreme became stronger than that in the present *** the contrary,the cooler climate displayed opposite changing characteristics relative to the warmer climate,ranging from the large-scale systems to local environments and to the *** summary,our study provides a promising approach to scientifically assess the response of precipitation extremes to climate change,making it feasible to perform ensemble simulations while investigating the multi-scale system interactions over the globe.

关键词： Precipitation extreme Climate change Pseudo-global-warming experiment Variable-resolution modeling Multi-scale system interaction

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Influence of Irregular Coastlines on a Tornadic Mesovortex in the Pearl River Delta during the Monsoon Season. Part Ⅰ:Pre-storm Environment and Storm Evolution

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Advances in Atmospheric Sciences 2024年第9期41卷 1115-1131页

作者： Lanqiang BAI Dan YAO Zhiyong MENG Yu ZHANG Xianxiang HUANG Zhaoming LI Xiaoding YU Foshan Tornado Research Center and China Meteorological Administration Tornado Key LaboratoryGuangdong Meteorological Serviceand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Guangdong 528000China meteorological Observation Centre CMABeijing 100081China department of Atmospheric and Oceanic Sciences and China Meteorological Administration Tornado Key LaboratorySchool of PhysicsPeking UniversityBeijing 100871China Guangzhou meteorological Observatory CMAGuangdong 511430China Foshan Tornado Research Center and China Meteorological Administration Tornado Key LaboratoryCMAGuangdong 528000China China meteorological Administration Training Center CMABeijing 528000China

The Pearl River Delta(PRD),a tornado hotspot,forms a distinct trumpet-shaped coastline that concaves toward the South China *** the summer monsoon season,low-level southwesterlies over the PRD’s sea surface tend to be turned toward the west coast,constituting a convergent wind field along with the landward-side southwesterlies,which influences regional convective *** two-part study explores the roles of this unique land–sea contrast of the trumpet-shaped coastline in the formation of a tornadic mesovortex within monsoonal flows in this *** I primarily presents observational analyses of pre-storm environments and storm *** rotating storm developed in a lowshear environment(not ideal for a supercell)under the interactions of three air masses under the influence of the land–sea contrast,monsoon,and storm cold *** intersection zone(or“triple point”)is typically characterized by local enhancements of ambient vertical vorticity and *** on a rapid-scan X-band phased-array radar,finger-like echoes were recognized shortly after the gust front intruded on the triple *** over the triple point,they rapidly wrapped up with a well-defined low-level *** is thus presumed that the triple point may have played roles in the mesovortex genesis,which will be demonstrated in Part II with multiple sensitivity numerical *** findings also suggest that when storms pass over the boundary intersection zone in the PRD,the expected possibility of a rotating storm occurring is relatively high,even in a low-shear *** knowledge of such environments provides additional guidance to assess the regional tornado risk.

关键词： tornado mesovortex surface boundary land–sea contrast monsoon

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ASLP-DL—A Novel Approach Employing Lightweight Deep Learning Framework for Optimizing Accident Severity Level Prediction

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Computers, Materials & Continua 2024年第2期78卷 2535-2555页

作者： Saba Awan Zahid Mehmood department of Software Engineering University of Engineering and TechnologyTaxila47050Pakistan department of Computer Engineering University of Engineering and TechnologyTaxila47050Pakistan

Highway safety researchers focus on crash injury severity,utilizing deep learning—specifically,deep neural networks(DNN),deep convolutional neural networks(D-CNN),and deep recurrent neural networks(D-RNN)—as the preferred method for modeling accident *** learning’s strength lies in handling intricate relation-ships within extensive datasets,making it popular for accident severity level(ASL)prediction and *** prior success,there is a need for an efficient system recognizing ASL in diverse road *** address this,we present an innovative Accident Severity Level Prediction Deep Learning(ASLP-DL)framework,incorporating DNN,D-CNN,and D-RNN models fine-tuned through iterative hyperparameter selection with Stochastic Gradient *** framework optimizes hidden layers and integrates data augmentation,Gaussian noise,and dropout regularization for improved *** and factor contribution analyses identify influential *** on three diverse crash record databases—NCDB 2018–2019,UK 2015–2020,and US 2016–2021—the D-RNN model excels with an ACC score of 89.0281%,a Roc Area of 0.751,an F-estimate of 0.941,and a Kappa score of 0.0629 over the NCDB *** proposed framework consistently outperforms traditional methods,existing machine learning,and deep learning techniques.

关键词： Injury severity prediction deep learning feature

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Phytochemical analysis,antioxidant,acetylcholinesterase,andα-amylase inhibitors from Hippeastrum hybridum extract

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Journal of Traditional Chinese Medicine 2024年第3期44卷 496-504页

作者： Naila Sher Mushtaq Ahmed Nadia Mushtaq department of Biotechnology University of Science and Technology Bannu-KPK 28100Pakistan department of Botany University of Science and Technology Bannu-KPK 28100Pakistan

OBJECTIVE:To investigate the effects of Hippeastrum hybridum(HH)as a free radical scavenger,and an inhibitor of the two enzymes i-e Alpha-amylase(α-amylase)and acetylcholinesterase(AChE).METHODS:In this study,HH plant was preliminary analyzed for phytochemical screening and then tested for its antioxidant,anti-α-amylase,and anti-AChE efficiency via standard ***:Phytochemical analysis shows the existence of different compounds;while Coumarins and quinones were *** total phenolic,flavonoid,and tannins content were found to be(78.52±0.69)mg GAE/g,(2.01±0.04)mg RUE/g,and(58.12±0.23)mg TAE/g of plant extract respectively.28.02%±0.02%alkaloid and 2.02%±0.05%saponins were present in the HH *** HH extract showed the anti-oxidant property with IC50(50%inhibition)of(151.01±0.13)(HH),(79.01±0.04)(Ascorbic acid)for ferric reducing,(91.48±0.13)(HH),(48.02±0.11)(Ascorbic acid)against Ammonium molybdenum,(156.02±0.31)(HH),(52.38±0.21)(Ascorbic acid)against DPPH,136.01±0.21(HH),52.02±0.31(Ascorbic acid)against H_(2)O_(2),and 154.12±0.03(HH),(40.05±0.15)(Ascorbic acid)μg/mL against ABTS *** analysis indicated that HH caused a competitive type of inhibition ofα-amylase(V_(max)remained constant and Km increases from 10.65 to84.37%)while Glucophage caused the un-competitive type of inhibition i-e both Km and V_(max)decreased from40.49 to 69.15%and 38.86 to 69.61%*** K_(i),(inhibition constant);K_(I),(dissociation constant),K_(m),(Michaelis-Menten constant),and IC50 were found to be62,364,68.1,and 38.08±0.22 for HH and 12,101.05,195,34.01±0.21 for ***,HH causes an anon-competitive type of inhibition of AChE i-e Km remains constant while V_(max)decreases from 60.5%to74.1%.The calculated K_(i),K_(I),K_(m),and IC50 were found to be 32,36.2,0.05,and 18.117±***:From the current results,it is concluded that HH extract contains bioactive compounds,and could be a good alternative to controlling oxidant

关键词： Hippeastrum hybridum phytochemicals antioxidant alpha-amylase acetylcholinesterase

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Analysis of b→cτν¯_(τ)anomalies using weak effective Hamiltonian with complex couplings and their impact on various physical observables

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Chinese Physics C 2024年第8期48卷 56-75页

作者： Muhammad Arslan Tahira Yasmeen Saba Shafaq Ishtiaq Ahmed Muhammad Jamil Aslam department of Physics Quaid-i-Azam UniversityIslamabad 45320Pakistan department of Physics International Islamic UniversityIslamabad 44000Pakistan National Center for Physics Islamabad 44000Pakistan

Recently,the experimental measurements of the branching ratios and different polarization asymmetries for processes occurring through flavor-changing-charged current(b→cτν¯_(τ))transitions by BABAR,Belle,and LHCb have revealed some significant differences from the corresponding Standard Model(SM)*** has triggered an interest to search for physics beyond the SM in the context of various new physics(NP)models and using the model-independent weak effective Hamiltonian(WEH).Assuming left-handed neutrinos,we add the dimension-six vector,(pseudo-)scalar,and tensor operators with complex Wilson coefficients(WCs)to the SM *** 60%,30%,and 10%constraints resulting from the branching ratio of B_(c)→τν¯_(τ),we reassess the parametric space of these new physics WCs accommodating the current anomalies based on the most recent HFLAV data of R_(τ/μ,e)(D)and R_(τ/μ,e)(D^(*))and Belle data of F_(L)(D^(*))and P_(τ)(D^(*)).We find that the allowed parametric region of left-handed scalar couplings strongly depends on the constraints of the B_(c)→τν¯_(τ)branching ratio,and the maximum pull from the SM predictions results from the<60%branching ratio ***,the parametric region changes significantly if we extend the analysis by adding LHCb data of R_(τ/μ)(J/ψ)and R_(τ/ℓ)(Λ_(c)).Furthermore,due to the large uncertainties in the measurements of R_(τ/μ)(J/ψ)and R_(τ/ℓ)(X_(c)),we derive the sum rules which complement them with R_(τ/μ,e)(D)and R_(τ/μ,e)(D^(*)).Using the best-fit points of the new complex WCs along with the latest measurements of R_(τ/μ,e)(D(^(*))),we predict the numerical values of the observable R_(τ/ℓ)(Λ_(c)),R_(τ/μ)(J/ψ),and R_(τ/ℓ)(X_(c))from the sum *** simultaneous dependence of abovementioned physical observables on the NP WCs is established by plotting their correlation with R_(D) and R_(D^(*)),which are useful to discriminate between various NP *** find that the most significant impact of NP results from the WC C^(S)_(L)=4C^(T).Fi

关键词： B meson anomalies new physics complex coupling HFLAV

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Cloud Microphysical Characteristics of Typhoon Meranti(2016)during Its Rapid Intensification:Model Validation and SST Sensitivity Experiments

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Journal of meteorological Research 2024年第3期38卷 542-557页

作者： Rui WANG Yihong DUAN Jianing FENG department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences Fudan UniversityShanghai200438China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing100081China

Cloud microphysics plays an important role in determining the intensity and precipitation of tropical cyclones(TCs).In this study,a high-resolution numerical simulation by WRF(version 4.2)of Typhoon Meranti(2016)during its rapid intensification(RI)period was conducted and validated by multi-source observations including Cloud-Sat and Global Precipitation Mission satellite *** snow and ice particles content were found to increase most rapidly compared with other hydrometeors during the RI *** all hydrometeors continued to *** graupel content only increased in the initial RI stage,and then decreased afterwards due to precipitation during the RI *** addition,sea surface temperature(SST)sensitivity experiments showed that,although the intensity of the TC increased with a higher SST,not all hydrometeors *** graupel content continued to increase with the increase in SST,mainly due to the accumulation of more lower-temperature supercooled water vapor at the corresponding *** content of snow decreased with the increase in SST because stronger vertical motion at the corresponding height affected the aggregation of ice crystals.

关键词： tropical cyclone rapid intensification cloud microphysical characteristics sea surface temperature(SST)

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Variable range hopping transport and dielectric relaxation mechanism in GdCrO_(3) rare-earth orthochromite perovskite

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Journal of Rare Earths 2024年第7期42卷 1304-1316,I0004页

作者： Muhammad Javed Ayaz Arif Khan Jamal Kazmi Naeem Akbar Said Nasir Khisro Amanullah Dar Aleem Dad Khan Tareen Mohd Ambri Mohamed department of Physics The University of Azad Jammu and KashmirMuzaffarabad13100Pakistan department of Physics University of Kotli Azad Jammu and KashmirKotli11100Pakistan Institute of Microengineering and Nanoelectronics Universiti Kebangsaan Malaysia43600BangiSelangorMalaysia department of Mathematics University of Kotli Azad Jammu and KashmirKotli11100Pakistan

The polycrystalline GdCrO_(3)(GCO)perovskite orthochromite was synthesized by the sol-gel auto-combustion *** Rietveld refined X-ray diffraction(XRD)profile of GCO confirms that the orthorhombic phase crystallizes in perovskite crystal structure with space group *** transmission electron microscopy and selected area electron diffraction divulge the polycrystalline nature of the perovskite *** field emission scanning electron microscopy(FESEM)images reveal the microstructural polyhedral growth of grains separated by sharp grain *** chemical states of the ions present in the compound were investigated by X-ray photoelectron spectroscopy(XPS)studies,and the electrical pathways were *** impedance studies were carried out in the experimental frequency and temperature ranges of 40 Hz-4 MHz and 178-408 K,*** equivalent circuit model(RGQG)(RGBQGB)resolves the impedance response into two contributions originating from the intra-grain and inter-granular micro-constituents of the *** electrical conduction mechanism is based on the Mott variable range hopping *** complex electric modulus studies demonstrate the short-and long-range mobility of the charge carriers and rule out the presence of electrode effects on the dielectric relaxation mechanism of the *** decreasing pattern of dielectric permittivity with frequency is explained by the Maxwell-Wagner type of *** frequency dependence of the loss factor exhibits the presence of thermally activated relaxation time distribution in the material.

关键词： Auto-combustion Perovskite Electro-ceramic Dielectric Electrical transport Impedance

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Cold plasma-induced effects on electromagnetic wave scattering in waveguides:a mode-matching analysis

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Communications in Theoretical Physics 2024年第3期76卷 144-156页

作者： Shahana Rizvi Muhammad Afzal department of Mathematics Capital University of Science and TechnologyIslamabadPakistan

This article presents advancements in an analytical mode-matching technique for studying electromagnetic wave propagation in a parallel-plate metallic rectangular *** technique involves projecting the solution onto basis functions and solving linear algebraic systems to determine scattering *** accuracy of this method is validated via numerical assessments,which involve the reconstruction of matching conditions and conservation *** study highlights the impact of geometric and material variations on reflection and transmission phenomena in the waveguide.

关键词： electromagnetic waves scattering cold plasma metallic conducting mode-matching technique

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Predicting PM_(2.5) Concentration in the Yangtze River Delta Region Using Climate System Monitoring Indices and Machine Learning

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Journal of meteorological Research 2024年第2期38卷 249-261页

作者： Jinghui MA Shiquan WAN Shasha XU Chanjuan WANG Danni QIU Shanghai Typhoon Institute Shanghai Meteorological ServiceShanghai 200030 Key Laboratory of Polar Atmosphere-Ocean-Iice System for Weather and Climate Ministry of EducationDepartment of Atmospheric and Oceanic SciencesFudan UniversityShanghai 200438 Shanghai Key Laboratory of Meteorology and Health Shanghai Meteorological ServiceShanghai 200030 Yangzhou meteorological Office Yangzhou 225001 department of Physics Yangzhou UniversityYangzhou 225003

Changing meteorological conditions during autumn and winter have considerable impact on air quality in the Yangtze River Delta(YRD)*** climatic factors,such as sea surface temperature and sea ice,together with the atmospheric circulation,directly affect meteorological conditions in the YRD region,thereby modulating the variation in atmospheric PM_(2.5) *** study used the evolutionary modeling machine learning technique to investigate the lag relationship between 144 climate system monitoring indices and autumn/winter PM_(2.5) concentration over 0-12 months in the YRD *** calculating the contribution ratios and lagged correlation coefficients of all indices over the previous 12 months,the top 36 indices were selected for model ***,the nine indices that contributed most to the PM_(2.5) concentration in the YRD region,including the decadal oscillation index of the Atlantic Ocean and the consistent warm ocean temperature index of the entire tropical Indian Ocean,were selected for physical mechanism *** evolutionary model was developed to forecast the average PM_(2.5) concentration in major cities of the YRD in autumn and winter,with a correlation coefficient of *** model testing,the correlation coefficient between the predicted and observed PM_(2.5) concentrations was in the range of 0.73-0.83 and the root-mean-square error was in the range of 9.5-11.6μg m-3,indicating high predictive *** model performed exceptionally well in capturing abnormal changes in PM_(2.5) concentration in the YRD region up to 50 days in advance.

关键词： PM_(2.5)concentration machine learning evolutionary modeling seasonal prediction

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