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Analytical investigation of second harmonic generation in metal nanoparticle trimers using dipole approximation
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作者 Afsoon Farhoomand Nasser Sepehri Javan Asef Kheirandish 《Communications in Theoretical Physics》 2025年第6期201-209,共9页
In this theoretical study,we investigate the generation of second harmonics(SH)during the interaction of a laser beam with a metallic nanoparticle(MNP)trimer.Utilizing a classical electrodynamics framework,we explore ... In this theoretical study,we investigate the generation of second harmonics(SH)during the interaction of a laser beam with a metallic nanoparticle(MNP)trimer.Utilizing a classical electrodynamics framework,we explore the nonlinear interactions between the laser beam fields and nanoparticles(NPs),accounting for dipole-dipole interactions among the particles.Analytical expressions are derived to quantify the impact of these interactions on SH radiation power for two distinct polarizations of the laser beam.Our findings indicate that when the laser electric field is aligned parallel to the trimer's symmetry axis,there is a significant enhancement in SH radiation power compared to a single non-interacting NP,accompanied by a red-shift in the plasmon resonance peak.Conversely,when the laser electric field is perpendicular to the trimer axis,the SH radiation power from each NP decreases,and the plasmon resonance peak experiences a blue-shift.Additionally,we examine the influence of particle size and interparticle separation on SH generation.These results provide valuable insights into the role of interparticle interactions in enhancing nonlinear optical processes in NP assemblies,with potential implications for the design of nanophotonic devices. 展开更多
关键词 nonlinear optical properties Drude model surface plasmon resonance dipole-dipole interaction radiation power second harmonic generation TRIMER
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Dromion structure in(2+1)-dimensional modulated positron-acoustic waves in a non-Maxwellian magnetoplasma
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作者 Aljawhara H Almuqrin Alim +5 位作者 B B Mouhammadoul C G L Tiofack A Mohamadou Sherif M E Ismaeel Weaam Alhejaili S A El-Tantawy 《Communications in Theoretical Physics》 2025年第5期171-183,共13页
This study investigates the dromion structure within the context of(2+1)-dimensional modulated positron-acoustic waves in a magnetoplasma consisting of inertial cold positrons and inertialess nonthermal hot electrons ... This study investigates the dromion structure within the context of(2+1)-dimensional modulated positron-acoustic waves in a magnetoplasma consisting of inertial cold positrons and inertialess nonthermal hot electrons and positrons as well as stationary positive ions.The reductive perturbation approach reduces the fluid governing equations to the plasma model to a Davey–Stewartson system.This study provides a detailed analysis of the influence of many related plasma parameters,including the density ratio of hot and cold positrons,the external magnetic field strength,the nonthermal parameter and the density ratio of electrons and cold positrons,on the growing rate of instability.Using the Hirota Bilinear method,it is found that the system supports some exact solutions,such as one-and two-dromion solutions.The change of plasma parameters significantly enhances the characteristics of dromion solutions.The elastic and inelastic collisions between two dromions are discussed at different times.The relevance of this study can help us to understand the various types of collision between energetic particles in confined plasma during the production of energy by thermonuclear fusion. 展开更多
关键词 Davey-Stewartson equations positron-acoustic waves modulational instability magnetoplasmas dromion soliton
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Influence of polarization of hot nuclear matter on the anomaly of surface diffuseness of inter-nuclear potential
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作者 S Ramezani Sani R Gharaei H A Rahnamaye Aliabad 《Communications in Theoretical Physics》 2025年第3期75-84,共10页
The fusion excitation functions for 12 colliding systems with 96≤Z_(1)Z_(2)≤608 are analyzed using coupled-channel(CC)calculations based on the M3Y double-folding(DF)potential supplemented with a repulsive potential... The fusion excitation functions for 12 colliding systems with 96≤Z_(1)Z_(2)≤608 are analyzed using coupled-channel(CC)calculations based on the M3Y double-folding(DF)potential supplemented with a repulsive potential that takes into account the incompressibility of the nuclear matter.We also applied the polarization effects of hot nuclear matter(PEHNM)on the calculations of the bare nucleus-nucleus interaction potential within the framework of the modified density-dependent Seyler-Blanchard(SB)approach in the T^(2)approximation.Our results reveal that we obtain a nice description of the experimental data of different fusion systems when we use the present theoretical approach to calculate the energy-dependent values of the fusion cross sections.In this paper,the influence of the PEHNM on the surface diffuseness parameter of the Woods-Saxon(WS)potential is also studied.In order to reach this goal,we extract the corresponding values of this parameter based on the modified form of the DF potential(M3Y+Repulsion+polarization).We find that the extracted values are located in a range between a=0.61 and 0.80 fm at different incident energies.It seems that the polarization effects of hot nuclear matter play a key role in describing the abnormally large values of the nuclear potential diffusenesses in the heavy-ion fusion reactions.Additionally,the regular decreasing trend for the diffuseness parameter of the nucleus-nucleus potential with the increase in the bombarding energies is also observed. 展开更多
关键词 Heavy-ion fusion reactions Seyler-Blanchard approach diffuseness parameter polarization effects
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Ground conditions and foundation types:Unraveling their impact on seismic response of high-rise buildings within dynamic soil-structure interaction
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作者 Xiaofeng Zhang Harry Far 《Earthquake Engineering and Engineering Vibration》 2025年第4期927-941,共15页
Structures modelled with flexible-base assumptions,incorporating soil effects,generally exhibit longer natural periods and higher damping compared to fixed-base models that exclude soil-structure interaction(SSI).Howe... Structures modelled with flexible-base assumptions,incorporating soil effects,generally exhibit longer natural periods and higher damping compared to fixed-base models that exclude soil-structure interaction(SSI).However,the beneficial or detrimental nature of SSI remains contentious in current earthquake damage analyses and research findings.This study introduces a numerical modelling technique,validated by experimental shaking table tests,to examine the effects of SSI on high-rise buildings.The study considers various substructure parameters,including foundation types,soil types,and bedrock depths.Both advantageous and adverse impacts of SSI are identified and analysed.Numerical simulations reveal that increased subsoil stiffness significantly amplifies the base shear of structures compared to bedrock depth effects.Additionally,increased foundation rocking results in higher inter-storey drifts and reduced base shear.Overall,SSI tends to amplify inter-storey drifts,indicating detrimental effects.Specifically,the study found that the inclusion of SSI increased maximum inter-storey drifts by up to 38%,particularly in softer soils,while reducing base shear by up to 44%in structures with classical compensated foundations on D_(e)and E_(e)soil types.In contrast,piled foundation systems experienced an increase in base shear of up to 27%under the same conditions.Conversely,SSI has beneficial impacts on base shear for structures with classical compensated foundations on soil types of D_(e)and E_(e),as it reduces the base shear.For structures with piled foundations and those with classical compensated foundations on C_(e)soil,SSI effects are detrimental.C_(e),D_(e),and E_(e)soils correspond to geotechnical classifications per AS1170,representing stiff,medium,and soft soils respectively.The study also presents minimum base shear ratios considering SSI reduction effects for various foundation types. 展开更多
关键词 recycled concrete frame-shear wall concealed bracings shaking table test nonlinear time-history response analysis
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Thyroid nodules as predictors of adenomatous colonic polyps:A systematic review and meta-analysis
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作者 Hyder Osman Mirghani Salah Alghamdi 《World Journal of Clinical Cases》 2025年第33期56-62,共7页
BACKGROUND Thyroid nodules(TN)are increasingly diagnosed worldwide;investigating the association between TN and colon polyps could be helpful in early detection and management.To our knowledge no meta-analysis has ass... BACKGROUND Thyroid nodules(TN)are increasingly diagnosed worldwide;investigating the association between TN and colon polyps could be helpful in early detection and management.To our knowledge no meta-analysis has assessed the relationship between TN and adenomatous colonic polyps.AIM To assess the association between adenomatous colonic polyps,thyroid-stimulating hormone,and TN.METHODS We searched PubMed,MEDLINE,Cochrane Library,EBSCO,and the first 100 articles in Google for articles published in English from inception until April 2025.We included prospective cohorts,retrospective studies,case-control studies,and cross-sectional studies.The keywords thyroid nodules,adenomatous colon polyps,thyroid volume,metabolic syndrome,insulin resistance,and thyroid malignancy were used.RESULTS Out of 237 articles,25 full texts were reviewed,and 5 full texts were included in the final meta-analysis.No relationship was found between TN,colonic polyps,and thyroid-stimulating hormone levels[odd ratio(OR):1.78,95%confidence interval(CI):0.55-5.74,P=0.33].Colonic polyps were more common among patients with TN when addressing heterogeneity(OR:0.42,95%CI:0.30-0.52,P<0.001 and OR:0.08,95%CI:0.70-0.86,P=0.85).CONCLUSION TN were similar among patients with and without adenomatous colonic polyps.However,TN was more common among colon polyps when addressing the heterogeneity.Thyroid-stimulating hormone was not different between those with and without TN.Age,sex,adiposity,and smoking effects might explain the higher rate observed by the included studies.Further studies controlling for the same are needed. 展开更多
关键词 Adenomatous colonic polyps Thyroid stimulating hormone Thyroid nodule PREDICTORS Risk factors
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Unlocking the engineering of solar-driven ZnO composites:From fundaments to sustainable and eco-friendly chemical energy
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作者 Irshad Ahmad Yifei Zhang +2 位作者 Ayman Al-Qattan S.AlFaify Gao Li 《Chinese Journal of Structural Chemistry》 2025年第11期85-120,共36页
Plastic pollution and elevated atmospheric CO_(2) levels remain critical environmental challenges,whereas methane is increasingly recognized as a valuable feedstock for producing high-value chemicals.Photocatalysis of... Plastic pollution and elevated atmospheric CO_(2) levels remain critical environmental challenges,whereas methane is increasingly recognized as a valuable feedstock for producing high-value chemicals.Photocatalysis offers a promising approach to harness abundant solar energy,converting it into sustainable and eco-friendly chemical energy for applications such as plastic degradation,CO_(2) reduction,and methane oxidation.ZnO-based composites stand out due to their large surface areas,tunable band structures,and abundant active sites,making them highly suitable for these photocatalytic processes.Nonetheless,pure ZnO is hindered by rapid recombination of photoinduced e^(-)/h^(+)pairs and limited absorption of visible light,restricting its photocatalytic efficiency.This review explores the fundamental mechanisms,synthesis strategies,and various ZnO-based composite materials that enhance photocatalytic plastic degradation,CO_(2) conversion,and methane oxidation.Special attention is paid to identifying key challenges and how the formation of ZnO composites addresses these issues within the different catalytic reaction pathways to improve overall photocatalytic activity.Finally,existing challenges and prospective research avenues are discussed to guide future advancements. 展开更多
关键词 PHOTOCATALYST ZNO Plastic waste CO_(2)reduction Methane oxidation
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Machine Learning-assisted Prediction of Polymer Glass Transition Temperature: A Structural Feature Approach
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作者 Bardia Afsordeh Hadi Shirali 《Chinese Journal of Polymer Science》 2025年第9期1661-1670,I0013,共11页
Machine learning(ML)has emerged as a powerful tool for predicting polymer properties,including glass transition temperature(Tg),which is a critical factor influencing polymer applications.In this study,a dataset of po... Machine learning(ML)has emerged as a powerful tool for predicting polymer properties,including glass transition temperature(Tg),which is a critical factor influencing polymer applications.In this study,a dataset of polymer structures and their Tg values were created and represented as adjacency matrices based on molecular graph theory.Four key structural descriptors,flexibility,side chain occupancy length,polarity,and hydrogen bonding capacity,were extracted and used as inputs for ML models:Extra Trees(ET),Random Forest(RF),Gaussian Process Regression(GPR),and Gradient Boosting(GB).Among these,ET and GPR achieved the highest predictive performance,with R2 values of 0.97,and mean absolute errors(MAE)of approximately 7–7.5 K.The use of these extracted features significantly improved the prediction accuracy compared to previous studies.Feature importance analysis revealed that flexibility had the strongest influence on Tg,followed by side-chain occupancy length,hydrogen bonding,and polarity.This work demonstrates the potential of data-driven approaches in polymer science,providing a fast and reliable method for Tg prediction that does not require experimental inputs. 展开更多
关键词 Machine learning Glass transition temperature Polymer structure Molecular graph theory Data-driven modeling
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Growth,Yield Components and Seed Nutritional Quality of Three Sesame(Sesamum Indicum L.)Cultivars Influenced by Different Levels of NaCl in Far North Region of Cameroon
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作者 Mathias Julien Hand Kingsley Mbi Tabi +3 位作者 Bogno Oumarou Salomon Ousman Victor Desire Taffouo Emmanuel Youmbi 《Journal of Agricultural Science and Technology(A)》 2025年第2期93-102,共10页
Context:In irrigated agriculture,the salt stress is a major problem due to accumulation of salt from the irrigation water in the soil layers.Objectives:The aim of this study is to determinate the effect of salinity on... Context:In irrigated agriculture,the salt stress is a major problem due to accumulation of salt from the irrigation water in the soil layers.Objectives:The aim of this study is to determinate the effect of salinity on some agromorphological traits and seed nutritional quality of three sesames(Sesamum indicum L.)varieties.Methodology:This is how four solutions of different NaCl concentrations from 0,60,120 to 240 mM were used to water sesame plants at the five-leaves stage and this for two months in completely randomized device with four repetitions.Results:The results show a negative effect of the salinity growth and yield parameters,mineral elements,ascorbic acid(to 21.4% in White cultivar,28% in Brown and 24.2% in Black cultivar from 0 to 240 mM NaCl),oil(to 22.6%in White cultivar,32% in Brown and 25.5% in Black cultivar from 0 to 240 mM NaCl)and accumulation of Na(Sodium)content(to 11.8% in White cultivar,15.3% in Brown and 12.2% in Black cultivar from 0 to 240 mM NaCl),osmolytes as proteins(to 14.5% in White cultivar,11.5% in Brown and 9.6%in Black cultivar from 0 to 240 mM NaCl)and antioxydants components.Varieties White and Brown were less affected by salinity.Conclusion:White variety exhibited higher adaptive potential under salinity stress when compared to Brown variety(rich in fiber)and closely followed by Black variety.Thus White variety could be recommended for consumer oil,minerals and proteins.As for Black variety,it could be used,as glucid and antioxydants additives in food. 展开更多
关键词 CAPSULE oil content SESAME SALINITY yield
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Assessment of the Biogas Potential by the Methanization of the Corn Crops in the Prefecture of Kindia (Guinea)
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作者 Facinet Camara Amadou Lamarana Bah +2 位作者 Mamadou Billo Doumbouya Idrissa Diaby Youssouf Conde 《Journal of Energy and Power Engineering》 2025年第1期10-20,共11页
The aim of this research is to assess the energy potential of cow dung and corn cob inputs,with a view to estimating their biogas potential.The inputs were characterized in the microbiology laboratory of the National ... The aim of this research is to assess the energy potential of cow dung and corn cob inputs,with a view to estimating their biogas potential.The inputs were characterized in the microbiology laboratory of the National Control Office Quality in Matoto,Conakry.The experiment to produce methane from cow dung and maize cob was carried out at the Applied Research in Natural Sciences Laboratory of the University of Kindia(UK)using the following equipment:Three digesters were each connected to an air chamber(gasometer)by means of flexible pipes 8 mm in diameter,connected by clamps,liquid adhesives,valves and Teflon.This research focused on determining the quantity of biogas contained in each type of substrate(cow dung,maize cob and their mixture).Three experiments on the methanization of these inputs were carried out,with anaerobic digestion lasting 27 days,in a temperature range of 27℃ to 31℃(mesophilic range).The results were as follows:maize cob 28.4 L,cow dung 22.6 L and codigestion 38.7 L.These results compared with similar studies revealed a coincidence. 展开更多
关键词 Cow dung corn cob physico-chemical parameters BIOGAS potential assessment
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A parameter study of how initial roughness and normal stress affect the flow and transport properties in granitic-like sheared synthetic fractures
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作者 Martin Stigsson Vladimir Cvetkovic +1 位作者 Diego Mas Ivars Jan-Olof Selroos 《Earth Energy Science》 2025年第4期306-323,共18页
Flow and transport properties of fractured crystalline rock are of great interest for different geotechnical ap-plications,such as storage of carbon dioxide,extraction of geothermal energy,or geologic storage of hazar... Flow and transport properties of fractured crystalline rock are of great interest for different geotechnical ap-plications,such as storage of carbon dioxide,extraction of geothermal energy,or geologic storage of hazardous waste.For the long-term safety assessment of geological storage of hazardous waste,the understanding of flow and transport properties through the network of fractures is essential.The flow and transport behaviour can be explored using numerical models to investigate what parameters that affect the results.In this work a pilot study is carried out for multiple realizations of single realistic fractures,using fractal theories,which then are nu-merically sheared using a semi-analytical algorithm.The aperture field is calculated using the average distance of the volume integral of the void that a 1 mm lateral displacement of the sheared surfaces generates.The flow field through the aperture field is solved using Reynolds lubrication equation in linear triangular finite elements.The transport properties,travel length,travel time,transport resistance and specific flow wetted surface,are calculated in a Lagrangian framework using 10,000 particles for each of the 128 flow fields.Evaluating these four metrics,varying initial roughness,4<JRC<10 and normal stress between 0.2 and 20 MPa during shearing,it is concluded that an increase in normal stress generally results in longer travel paths,longer travel times,higher transport resistance and larger specific flow wetted surface while an increase of initial roughness will generally result in longer travel paths,shorter travel times,lower transport resistance and smaller specific flow wetted surface. 展开更多
关键词 Aperture distribution FLOW Fractal Normal stress ROUGHNESS SELF-AFFINE SHEARING Transport properties
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Congenital scoliosis with truncus arteriosus type 1 in a preterm neonate:A case report
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作者 Pius Omullo Khulud Mahmood Nurani +2 位作者 Kimiya Shahabi Ooko Emma Brian Mutuku 《World Journal of Clinical Pediatrics》 2025年第3期368-374,共7页
BACKGROUND Congenital scoliosis(CS)is a spinal deformity caused by defective segmentation and development of vertebrae during early embryogenesis.It occurs in 0.5%-1%in 1000 births and may rarely occur with congenital... BACKGROUND Congenital scoliosis(CS)is a spinal deformity caused by defective segmentation and development of vertebrae during early embryogenesis.It occurs in 0.5%-1%in 1000 births and may rarely occur with congenital defects affecting the heart or genitourinary system.Truncus arteriosus(TA)is a life-threatening cardiac defect in which a single arterial trunk supplies both systemic and pulmonary circulation,leading to complications such as pulmonary hypertension,heart failure,and severe hypoxia.Although rare individually,the co-occurrence of both conditions poses unique diagnostic and therapeutic challenges,with limited documentation in medical literature.CASE SUMMARY We present a 36-week preterm neonate with CS associated with TA type 1,pre-senting with respiratory distress,cyanosis,and altered spinal curvature.This case demonstrates the complexity of managing neonates with multiple congenital de-fects.Here,the patient was managed with oxygen supplementation,heart failure medication,nasogastric feeding,and multidisciplinary care to optimize her for surgical corrections.A coordinated,interdisciplinary approach was employed to optimize outcomes,particularly in a resource-limited setting.Immediate re-spiratory and cardiovascular stabilization and long-term orthopedic and cardiac interventions were central to improving the patient’s quality of life and survival.CONCLUSION Recognizing co-existing congenital anomalies and their embryological interre-lation is critical in holistic patient care,particularly during neonatal and infancy. 展开更多
关键词 Congenital scoliosis Truncus arteriosus Preterm neonate Corrective surgery Congenital heart disease Case report
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Pollen source affects acorn production in pedunculate oak(Quercus robur L.)
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作者 Ryan McClory Richard H.Ellis +1 位作者 Martin Lukac Jo Clark 《Journal of Forestry Research》 2025年第1期77-85,共9页
Acorn production in oaks(Quercus spp.)shows considerable inter-annual variation,known as masting.The effects of pollen sourced from trees within or outside the stand on acorn production were investigated in pedunculat... Acorn production in oaks(Quercus spp.)shows considerable inter-annual variation,known as masting.The effects of pollen sourced from trees within or outside the stand on acorn production were investigated in pedunculate oak(Quercus robur L.)in an ancient mixed woodland during two moderate masting years.Comparisons were made between natural pollination,hand pollinations with out-of-stand pollen,in-stand pollen or a 1:1 combination of the two pollen sources,and for bagged flowers left unpollinated.After all treatments,>85%of the flowers or developing acorns were aborted between May and August of both years.When flowers were protected with pollen bags and no pollen added,no acorns were produced.In contrast,hand pollination with out-of-stand pollen produced the most acorns both years and significantly more than within-stand pollen or natural pollination in 2022.Hand pollination with out-of-stand or within-stand pollen provided significantly more acorns than natural pollination in 2023.In 2022,hand pollination with a 1:1 mixture of out-of-stand and within-stand pollen yielded an intermediate number of mature acorns between those for the out-of-stand and within-stand pollination treatments.The study provides clear evidence of maternal choice during acorn development in pedunculate oak and of the benefits of pollen supplementation.It also confirms that pedunculate oak is a fruit-maturation masting species;abortion of pollinated flowers and immature acorns determines a mast year(rather than the number of flowers produced)at this site. 展开更多
关键词 Quercus robur L. ACORNS MASTING Pedunculate oak POLLINATION
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Long-period Double-lined Eclipsing Binaries:The System V454 Aur with the Secondary Eclipse Caused by the Occultation of the Hotter Component
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作者 Alexei Y.Kniazev Oleg Malkov +2 位作者 Stanislav Gorda Leonid N.Berdnikov Ivan Y.Katkov 《Research in Astronomy and Astrophysics》 2025年第2期239-253,共15页
We present the results of our study of the long-period eclipsing binary star V454 Aur.The results are based on spectroscopic data obtained with the UFESéchelle spectrograph and photometric observations from Trans... We present the results of our study of the long-period eclipsing binary star V454 Aur.The results are based on spectroscopic data obtained with the UFESéchelle spectrograph and photometric observations from Transiting Exoplanet Survey Satellite(TESS).The derived radial velocity curve is based on 17 spectra obtained between 2021and 2023,covering all orbital phases of this binary system.The orbital period determined from TESS data,P=27.019803±0.000003 days,agrees within uncertainties with the period established in previous studies.The model constructed for the TESS photometric light curve achieves a precision of 0.01%.The effective temperatures of both components,as well as the system metallicity,were directly derived from the spectra and are Teff,A=6250±50 K,Teff,B=5855±50 K,and[Fe/H]=-0.10±0.08,respectively.Our analysis of the photometric and spectroscopic data allowed us to directly compute the luminosities of the components,LA=1.82 L☉and LB=1.07 L☉,their radii,RA=1.15 R☉and RB=1.00 R☉,and their masses,MA=1.137 M☉and MB=1.023 M☉,with uncertainties below 1%.Comparison with evolutionary tracks indicates that the system’s age is 1.18±0.10 Gyr,and both components are still on the main sequence.The V454 Aur system is particularly interesting due to the partial eclipse of the primary component,which results in the“inversion”of the primary and secondary minima in the photometric light curve. 展开更多
关键词 stars:luminosity function mass function (stars:)binaries:spectroscopic stars:individual(V454 Aur)
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Predicting gross primary productivity of poplar plantations based on solar-induced chlorophyll fluorescence using an improved machine learning model
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作者 Yiheng Wang Zhipeng Li +2 位作者 Jinsong Zhang Joanna Simms Xin Wang 《Forest Ecosystems》 2025年第6期1097-1109,共13页
Gross primary production(GPP)is closely associated with processes such as photosynthesis and transpiration within ecosystems,which is a vital component of the global carbon-water-energy cycle.Accurate prediction of GP... Gross primary production(GPP)is closely associated with processes such as photosynthesis and transpiration within ecosystems,which is a vital component of the global carbon-water-energy cycle.Accurate prediction of GPP in terrestrial ecosystems is essential for evaluating terrestrial carbon cycle processes.Machine learning(ML)models provide significant technical support in this domain.Presently,there is a deficiency of high-precision and robust GPP prediction variables and models.Challenges such as unclear contributions of predictive variables,extended model training durations,and limited robustness must be addressed.Solar-induced chlorophyll fluorescence(SIF),optimized multilayer perceptron neural networks,and ensemble learning models show the potential to overcome these challenges.This study aimed to develop an optimized multilayer perceptron neural network model and an ensemble learning model,while objectively assessing the capacity of SIF to predict GPP.Identifying robust models capable of enhancing the accuracy of GPP predictions was the ultimate goal.This study utilized continuous observations of SIF and meteorological data collected from 2020 to 2021 at a designated research observation station within the Populus plantation ecosystem of the Huanghuaihai agricultural protective forest system in Henan Province,China.By optimizing and evaluating the predictive accuracy and robustness of the models across different temporal scales(half-hourly and daily scales),a multi-layer perceptron(MLP)neural network optimization model based on the back propagation(BP)neural network(BPNN)algorithm(BP/MLP)and MLP and random forest(RF)integration(MLP-RF)ensemble models were constructed,utilizing SIF as the primary predictive variable for GPP.Both the BP/MLP(half-hourly scale model R^(2)=0.885,daily scale model R^(2)=0.921)and the MLP-RF(half-hourly scale model R^(2)=0.845,daily scale model R^(2)=0.914)models showed superior accuracy compared to the BPNN(half-hourly scale model R^(2)=0.841,daily scale model R^(2)=0.918)and the traditional RF(half-hourly scale model R^(2)=0.798,daily scale model R^(2)=0.867)models,with the BP/MLP model consistently outperforming the MLP-RF model.The BP/MLP model,which was optimized through particle swarm optimization(PSO),significantly enhanced the robustness of GPP predictions on a half-hourly scale and daily scale.Considering both half-hourly scale and daily scale in the PSO-BP/MLP modeling,the four indicators,light-use efficiency(LUE),photosynthetically active radiation(PAR),absorbed photosynthetically active radiation(APAR),and the variation in SIF with NIRvP(fSIF(NIRvP)),exhibited the potential for enhancing the accuracy of GPP predictions.This study employed a series of model optimization techniques to develop a GPP prediction model with enhanced performance that objectively evaluated the contributions of the predictive variables.This approach provided an innovative and effective method for assessing the carbon cycle in terrestrial ecosystems. 展开更多
关键词 Gross primary productivity Solar-induced chlorophyll fluorescence(SIF) Integrated learning Particle swarm optimization(PSO) Predictive modeling
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Wideband Polarized Emissions from PSR J1938+2213
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作者 Shu Ma De-Hua Wang +3 位作者 Shuang-Qiang Wang Fei-Fei Kou Sheng-Nan Sun Na Wang 《Research in Astronomy and Astrophysics》 2025年第8期243-250,共8页
We present a wideband polarization analysis of the mode-changing pulsar PSR J1938+2213 using the ultra-wideband low-frequency receiver on Murriyang,the Parkes 64 m radio telescope.Polarization profiles for both the bu... We present a wideband polarization analysis of the mode-changing pulsar PSR J1938+2213 using the ultra-wideband low-frequency receiver on Murriyang,the Parkes 64 m radio telescope.Polarization profiles for both the burst and weak emission modes are obtained.We find that the pulse widths of the two modes exhibit distinct frequency dependencies:the pulse width increases with frequency in the burst mode,but decreases in the weak mode.The linear and circular polarization fractions also show different trends with frequency between the two modes.Our spectral analysis shows that both modes follow power-law spectra,but with differing spectral indices. 展开更多
关键词 (stars:)pulsars:general stars:neutron methods:data analysis
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MANPOWER study:Real-world post-hoc analysis assessing essential phospholipids for non-alcoholic fatty liver disease from the Russian registry
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作者 Asad Izziddin Dajani Branko Popovic +3 位作者 Caroline Amand Sabine Tong Kirill Maximovich Starostin Victor Goncharuk 《World Journal of Hepatology》 2025年第6期139-152,共14页
BACKGROUND Since non-alcoholic fatty liver disease(NAFLD)is associated with abnormal liver function tests,treatment recommendations aim to reduce the level of known markers of liver inflammation,such as alanine transa... BACKGROUND Since non-alcoholic fatty liver disease(NAFLD)is associated with abnormal liver function tests,treatment recommendations aim to reduce the level of known markers of liver inflammation,such as alanine transaminase(ALT),aspartate transaminase(AST)and gamma-glutamyl transferase(GGT).Essential phospholipids(EPLs)have been shown to reduce levels of these liver enzymes and improve ultrasonographic features.While non-invasive diagnostic tests have been developed to stage inflammation,these tests were not specifically designed to evaluate patients with NAFLD.This highlights the need to describe the liver enzyme profile across the different levels of NAFLD severity for improved grading and staging of NAFLD.AIM To describe liver enzyme profiles across NAFLD severity to inform a diagnostic staging algorithm and identify who may benefit from EPLs.METHODS This post-hoc analysis of the observational MANPOWER study included 2843 adult patients with newly diagnosed NAFLD.The primary endpoint was assessment of baseline liver enzyme profiles.Secondary endpoints were effectiveness of Essentiale®(an EPL)on liver enzyme levels and ultrasonography findings across three definitions of NAFLD:(1)Statistical distribution of liver enzyme levels;(2)MANPOWER cut-offs;and(3)Presence of physiciandiagnosed non-alcoholic steatohepatitis.The best performing algorithm was used to describe the risk factors and profiles associated with increased liver enzyme levels.RESULTS Of the 2843 patients included in this post-hoc analysis,most were female(62.2%),with a mean age of 48.4 years(SD 8.59 years).Overall,mean levels of ALT,AST and GGT increased with NAFLD severity for all three subgroups,with the rate of chronic comorbidities correlated with NAFLD severity.Across each subgroup of interest,Essentiale significantly reduced average liver enzyme levels and improved ultrasonography features,including diffuse liver hyperechogenicity and heterogeneous liver structure(P<0.05),with greater benefit associated with increased severity.Compared with all algorithms tested,the algorithm based on the statistical distribution of liver enzymes displayed the highest accuracy,sensitivity and specificity for the grading and staging of NAFLD and could form the basis of a diagnostic algorithm.CONCLUSION Liver enzyme profiles may identify NAFLD severity and allow monitoring of therapeutic response.Essentiale may improve liver enzyme levels and ultrasonography features.An algorithm could aid in the diagnosis/staging of NAFLD. 展开更多
关键词 Algorithms Essential phospholipids Liver enzymes Non-alcoholic fatty liver disease ULTRASONOGRAPHY
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A comprehensive review on the nutritional composition,bioactive potential,encapsulation techniques,and food system applications of guava(Psidium guajava L.)leaves
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作者 Anjali Sahal Siddhant Chaudhary +5 位作者 Afzal Hussain Shubhangi Arora Ankita Dobhal Waseem Ahmad Vinod Kumar Sanjay Kumar 《Grain & Oil Science and Technology》 2025年第1期64-74,共11页
Guava(Psidium guajava L.),a plant belonging to the Myrtaceae family,holds significant medicinal and nutritional values.Leaves of the plant are described to be elliptical with a dark green color and are utilized in the... Guava(Psidium guajava L.),a plant belonging to the Myrtaceae family,holds significant medicinal and nutritional values.Leaves of the plant are described to be elliptical with a dark green color and are utilized in the treatment of gastrointestinal and respiratory issues along with increasing the platelet count in patients suffering from dengue.In this review paper,the nutritional composition and bioactive compounds of guava leaves,including proteins,vitamins,minerals,and polysaccharides,have been reviewed.The methods of extraction of bioactive compounds from guava leaves and their bioactivities,including antioxidant,anti-diabetic,and anti-cancer potential,have been explored.Further,encapsulation techniques for improving the transport of bioactive compounds and living cells into foods have been studied.The application of guava leaves in different food systems such as herbal tea,pork sausage,chocolates,jelly,meals for chickens,functional beverages,and as antibacterial agents in food preservatives has also been investigated.The findings of this review illustrated that the phytochemicals present in guava leaves showed excellent antimicrobial and antioxidant properties.Encapsulation appears to be a promising technique for improving the stability,bioavailability,and controlled release of bioactive chemicals extracted from guava leaves.Different methods for the encapsulation of bioactive compounds employed and applied in distinct food systems showed preservation of phytochemicals,improved bioactivities,and nutritional values.Overall,this review paper demonstrated how guava leaves,an abundant source of bioactive compounds,can be used as a multipurpose component to create functional foods,edible coatings,and active packaging to enhance the nutritional,antioxidant,and antimicrobial properties of various food systems that have qualities that promote health. 展开更多
关键词 Psidium guajava L. BIOAVAILABILITY EXTRACTION ENCAPSULATION Food system
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Ultrahigh-resolution atomic localization via superposition of standing waves
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作者 Muhammad Idrees Ahmed S Hendy Zareen A Khan 《Communications in Theoretical Physics》 2025年第3期57-65,共9页
In this study we theoretically demonstrate ultrahigh-resolution two-dimensional atomic localization within a three-levelλ-type atomic medium via superposition of asymmetric and symmetric standing wave fields.Our anal... In this study we theoretically demonstrate ultrahigh-resolution two-dimensional atomic localization within a three-levelλ-type atomic medium via superposition of asymmetric and symmetric standing wave fields.Our analysis provides an understanding of the precise spatial localization of atomic positions at the atomic level,utilizing advanced theoretical approaches and principles of quantum mechanics.The dynamical behavior of a three-level atomic system is thoroughly analyzed using the density matrix formalism within the realm of quantum mechanics.A theoretical approach is constructed to describe the interaction between the system and external fields,specifically a control field and a probe field.The absorption spectrum of the probe field is thoroughly examined to clarify the spatial localization of the atom within the proposed configuration.A theoretical investigation found that symmetric and asymmetric superposition phenomena significantly influence the localized peaks within a two-dimensional spatial domain.Specifically,the emergence of one and two sharp localized peaks was observed within a one-wavelength domain.We observed notable influences of the intensity of the control field,probe field detuning and decay rates on atomic localization.Ultimately,we have achieved an unprecedented level of ultrahigh resolution and precision in localizing an atom within an area smaller thanλ/35×λ/35.These findings hold promise for potential applications in fields such as Bose-Einstein condensation,nanolithography,laser cooling,trapping of neutral atoms and the measurement of center-of-mass wave functions. 展开更多
关键词 ultrahigh resolution atom localization symmetric and asymmetric superposition probe absorption standing wave fields
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A review of photovoltaic/thermal(PV/T)incorporation in the hydrogen production process
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作者 Hussein A.Kazem Miqdam T.Chaichan +4 位作者 Ali H.A.Al-Waeli K.Sopian Waheeb E.Alnaser Lawrence Kazmerski Naser W.Alnaser 《Global Energy Interconnection》 2025年第3期363-393,共31页
Integrating the photovoltaic/thermal(PV/T)system in green hydrogen production is an improvement in sustainable energy technologies.In PV/T systems,solar energy is converted into electricity and thermal energy simultan... Integrating the photovoltaic/thermal(PV/T)system in green hydrogen production is an improvement in sustainable energy technologies.In PV/T systems,solar energy is converted into electricity and thermal energy simultaneously using hot water or air together with electricity.This dual use saves a significant amount of energy and officially fights greenhouse gases.Different cooling techniques have been proposed in the literature for improving the overall performance of the PV/T systems;employing different types of agents including nanofluids and phase change materials.Hydrogen is the lightest and most abundant element in the universe and has later turned into a flexible energy carrier for transportation and other industrial applications.Issues,including the processes of Hydrogen manufacturing,preservation as well as some risks act as barriers.This paper provides an analysis of several recent publications on the efficiency of using PV/T technology in the process of green hydrogen production and indicates the potential for its increased efficiency as compared to conventional systems that rely on fossil fuels.Due to the effective integration of solar energy,the PV/T system can play an important role in the reduction of the levelized cost of hydrogen(LCOH)and hence play an important part in reducing the economic calculations of the decarbonized energy system. 展开更多
关键词 PV/T Green hydrogen PRODUCTION Liquification Technology readiness levels Levelized cost of hydrogen
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