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MODELING OF A MICROPOLAR THIN FILM FLOW WITH RAPIDLY VARYING THICKNESS AND NON-STANDARD BOUNDARY CONDITIONS
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作者 María ANGUIANO Francisco Javier SUÁREZ-GRAU 《Acta Mathematica Scientia》 2026年第1期209-242,共34页
In this paper,we study the asymptotic behavior of the micropolar fluid flow through a thin domain,assuming zero Dirichlet boundary condition on the top boundary,which is rapidly oscillating,and non-standard boundary c... In this paper,we study the asymptotic behavior of the micropolar fluid flow through a thin domain,assuming zero Dirichlet boundary condition on the top boundary,which is rapidly oscillating,and non-standard boundary conditions on the flat bottom.Assuming“Reynolds roughness regime”,in which the thickness of the domain is very small compared to the wavelength of the roughness(i.e.a very slight roughness),we rigorously derive a generalized Reynolds equation for pressure,clearly showing the roughness-induced effects.Moreover,we give expressions for the average velocity and microrotation. 展开更多
关键词 micropolar fluid thin-film flow rapidly oscillating boundary nonzero boundary conditions HOMOGENIZATION
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An Improved PID Controller Based on Artificial Neural Networks for Cathodic Protection of Steel in Chlorinated Media
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作者 JoséArturo Ramírez-Fernández Henevith G.Méndez-Figueroa +3 位作者 Sebastián Ossandón Ricardo Galván-Martínez MiguelÁngel Hernández-Pérez Ricardo Orozco-Cruz 《Computers, Materials & Continua》 2026年第3期624-640,共17页
In this study,artificial neural networks(ANNs)were implemented to determine design parameters for an impressed current cathodic protection(ICCP)prototype.An ASTM A36 steel plate was tested in 3.5%NaCl solution,seawate... In this study,artificial neural networks(ANNs)were implemented to determine design parameters for an impressed current cathodic protection(ICCP)prototype.An ASTM A36 steel plate was tested in 3.5%NaCl solution,seawater,and NS4 using electrochemical impedance spectroscopy(EIS)to monitor the evolution of the substrate surface,which affects the current required to reach the protection potential(Eprot).Experimental data were collected as training datasets and analyzed using statistical methods,including box plots and correlation matrices.Subsequently,ANNs were applied to predict the current demand at different exposure times,enabling the estimation of electrochemical parameters(limiting voltage values)that can be used to optimize a self-regulating ICCP system.The obtained electrochemical parameters were then used,through Particle Swarm Optimization(PSO),to fine-tune an ANN-based proportional-integral-derivative(PID)controller for the ICCP system. 展开更多
关键词 Artificial neural networks(ANNs) corrosion impressed current cathodic protection(ICCP) proportional integral derivative(PID)corrosion control particle swarm optimization(PSO) statistical analysis
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Neuroprotection provided by polyphenols and flavonoids in photoreceptor degenerative diseases
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作者 Théo Henrique de Lima-Vasconcellos Gabrieli Bovi dos Santos +4 位作者 Marília Inês Móvio Giovanna Klemenc Donnici Gabriela Maria Badin Daniele Ribeiro de Araujo Alexandre Hiroaki Kihara 《Neural Regeneration Research》 2026年第3期908-922,共15页
The intricate landscape of neurodegenerative diseases complicates the search for effective therapeutic approaches.Photoreceptor degeneration,the common endpoint in various retinal diseases,including retinitis pigmento... The intricate landscape of neurodegenerative diseases complicates the search for effective therapeutic approaches.Photoreceptor degeneration,the common endpoint in various retinal diseases,including retinitis pigmentosa and age-related macular degeneration,leads to vision loss or blindness.While primary cell death is driven by genetic mutations,oxidative stress,and neuroinflammation,additional mechanisms contribute to disease progression.In retinitis pigmentosa,a multitude of genetic alterations can trigger the degeneration of photoreceptors,while other retinopathies,such as agerelated macular degeneration,are initiated by combinations of environmental factors,such as diet,smoking,and hypertension,with genetic predispositions.Nutraceutical therapies,which blend the principles of nutrition and pharmaceuticals,aim to harness the health benefits of bioactive compounds for therapeutic applications.These compounds generally possess multi-target effects.Polyphenols and flavonoids,secondary plant metabolites abundant in plant-based foods,are known for their antioxidant,neuroprotective,and anti-inflammatory properties.This review focuses on the potential of polyphenols and flavonoids as nutraceuticals to treat neurodegenerative diseases such as retinitis pigmentosa.Furthermore,the importance of developing reliable delivery methods to enhance the bioavailability and therapeutic efficacy of these compounds will be discussed.By combining nutraceuticals with other emerging therapies,such as genetic and cell-based treatments,it is possible to offer a more comprehensive approach to treating retinal degenerative diseases.These advancements could lead to a viable and accessible option,improving the quality of life for patients with retinal diseases. 展开更多
关键词 FLAVONOIDS NEUROINFLAMMATION nutraceutical therapy oxidative stress retinitis pigmentosa
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Detection of Maliciously Disseminated Hate Speech in Spanish Using Fine-Tuning and In-Context Learning Techniques with Large Language Models
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作者 Tomás Bernal-Beltrán RonghaoPan +3 位作者 JoséAntonio García-Díaz María del Pilar Salas-Zárate Mario Andrés Paredes-Valverde Rafael Valencia-García 《Computers, Materials & Continua》 2026年第4期353-390,共38页
The malicious dissemination of hate speech via compromised accounts,automated bot networks and malware-driven social media campaigns has become a growing cybersecurity concern.Automatically detecting such content in S... The malicious dissemination of hate speech via compromised accounts,automated bot networks and malware-driven social media campaigns has become a growing cybersecurity concern.Automatically detecting such content in Spanish is challenging due to linguistic complexity and the scarcity of annotated resources.In this paper,we compare two predominant AI-based approaches for the forensic detection of malicious hate speech:(1)finetuning encoder-only models that have been trained in Spanish and(2)In-Context Learning techniques(Zero-and Few-Shot Learning)with large-scale language models.Our approach goes beyond binary classification,proposing a comprehensive,multidimensional evaluation that labels each text by:(1)type of speech,(2)recipient,(3)level of intensity(ordinal)and(4)targeted group(multi-label).Performance is evaluated using an annotated Spanish corpus,standard metrics such as precision,recall and F1-score and stability-oriented metrics to evaluate the stability of the transition from zero-shot to few-shot prompting(Zero-to-Few Shot Retention and Zero-to-Few Shot Gain)are applied.The results indicate that fine-tuned encoder-only models(notably MarIA and BETO variants)consistently deliver the strongest and most reliable performance:in our experiments their macro F1-scores lie roughly in the range of approximately 46%–66%depending on the task.Zero-shot approaches are much less stable and typically yield substantially lower performance(observed F1-scores range approximately 0%–39%),often producing invalid outputs in practice.Few-shot prompting(e.g.,Qwen 38B,Mistral 7B)generally improves stability and recall relative to pure zero-shot,bringing F1-scores into a moderate range of approximately 20%–51%but still falling short of fully fine-tuned models.These findings highlight the importance of supervised adaptation and discuss the potential of both paradigms as components in AI-powered cybersecurity and malware forensics systems designed to identify and mitigate coordinated online hate campaigns. 展开更多
关键词 Hate speech detection malicious communication campaigns AI-driven cybersecurity social media analytics large language models prompt-tuning fine-tuning in-context learning natural language processing
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Fluid Forces on a Hydrofoil for Kitefoil and Windfoil Boards:Experimental Investigation on Their Dependence on the Froude Number Based on Submergence
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作者 H.Martínez-Barberá J.Calderon-Sanchez +1 位作者 L.Moulian A.Souto-Iglesias 《哈尔滨工程大学学报(英文版)》 2026年第1期1-14,共14页
Races using kitefoil and windfoil surfboards have been in the Olympic Games for the first time in Paris 2024,signalling their relevance in sailing sports.However,the dynamics of these devices is yet not well understoo... Races using kitefoil and windfoil surfboards have been in the Olympic Games for the first time in Paris 2024,signalling their relevance in sailing sports.However,the dynamics of these devices is yet not well understood,in particular the influence on the hydrodynamic forces and moments of the distance of the foil to the free surface.Considering this,the present paper documents an experimental investigation in which forces and torque produced,under uniform flow,by a full-scale state-of-the-art hydrofoil(suitable both for kitesurf and windsurf)were measured.A range of velocities,angles of attack,and submergences were tested,leading to Froude numbers based on submergence with maximum values around five,a typical range in actual sailing conditions.From these tests,formulae for the hydrodynamic coefficients have been proposed.They can be used for developing Velocity Prediction Programs(VPP)for this kind of craft,a necessary tool to plan racing configurations and to analyze their racing performance.With the aim of making the experimental data useful for benchmarking numerical models and for future research on related topics such as foil ventilation and transition to turbulence,the specimen’s 3D file is provided as supplementary material to this paper. 展开更多
关键词 HYDROFOIL Kitefoil Windfoil Velocity prediction programs Lift coefficient Drag coefficient
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5DGWO-GAN:A Novel Five-Dimensional Gray Wolf Optimizer for Generative Adversarial Network-Enabled Intrusion Detection in IoT Systems 被引量:1
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作者 Sarvenaz Sadat Khatami Mehrdad Shoeibi +2 位作者 Anita Ershadi Oskouei Diego Martín Maral Keramat Dashliboroun 《Computers, Materials & Continua》 SCIE EI 2025年第1期881-911,共31页
The Internet of Things(IoT)is integral to modern infrastructure,enabling connectivity among a wide range of devices from home automation to industrial control systems.With the exponential increase in data generated by... The Internet of Things(IoT)is integral to modern infrastructure,enabling connectivity among a wide range of devices from home automation to industrial control systems.With the exponential increase in data generated by these interconnected devices,robust anomaly detection mechanisms are essential.Anomaly detection in this dynamic environment necessitates methods that can accurately distinguish between normal and anomalous behavior by learning intricate patterns.This paper presents a novel approach utilizing generative adversarial networks(GANs)for anomaly detection in IoT systems.However,optimizing GANs involves tuning hyper-parameters such as learning rate,batch size,and optimization algorithms,which can be challenging due to the non-convex nature of GAN loss functions.To address this,we propose a five-dimensional Gray wolf optimizer(5DGWO)to optimize GAN hyper-parameters.The 5DGWO introduces two new types of wolves:gamma(γ)for improved exploitation and convergence,and theta(θ)for enhanced exploration and escaping local minima.The proposed system framework comprises four key stages:1)preprocessing,2)generative model training,3)autoencoder(AE)training,and 4)predictive model training.The generative models are utilized to assist the AE training,and the final predictive models(including convolutional neural network(CNN),deep belief network(DBN),recurrent neural network(RNN),random forest(RF),and extreme gradient boosting(XGBoost))are trained using the generated data and AE-encoded features.We evaluated the system on three benchmark datasets:NSL-KDD,UNSW-NB15,and IoT-23.Experiments conducted on diverse IoT datasets show that our method outperforms existing anomaly detection strategies and significantly reduces false positives.The 5DGWO-GAN-CNNAE exhibits superior performance in various metrics,including accuracy,recall,precision,root mean square error(RMSE),and convergence trend.The proposed 5DGWO-GAN-CNNAE achieved the lowest RMSE values across the NSL-KDD,UNSW-NB15,and IoT-23 datasets,with values of 0.24,1.10,and 0.09,respectively.Additionally,it attained the highest accuracy,ranging from 94%to 100%.These results suggest a promising direction for future IoT security frameworks,offering a scalable and efficient solution to safeguard against evolving cyber threats. 展开更多
关键词 Internet of things intrusion detection generative adversarial networks five-dimensional binary gray wolf optimizer deep learning
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Benchmarking the composite performance of distinct shapes of ferrometallic gold nanoshells:photothermal cancer therapy 被引量:1
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作者 Sara I.Abdelsalam Essam T.Abdelwahab +2 位作者 I.M.Eldesoky Ramzy M.Abumandour M.M.Ahmed 《Acta Mechanica Sinica》 2025年第6期3-15,共13页
This article presents a detailed theoretical hybrid analysis of the magnetism and the thermal radiative heat transfer in the presence of heat generation affecting the behavior of the dispersed gold nanoparticles(AuNPs... This article presents a detailed theoretical hybrid analysis of the magnetism and the thermal radiative heat transfer in the presence of heat generation affecting the behavior of the dispersed gold nanoparticles(AuNPs)through the blood vessels of the human body.The rheology of gold-blood nanofluid is treated as magnetohydrodynamic(MHD)flow with ferromagnetic properties.The AuNPs take different shapes as bricks,cylinders,and platelets which are considered in changing the nanofluid flow behavior.Physiologically,the blood is circulated under the kinetics of the peristaltic action.The mixed properties of the slip flow,the gravity,the space porosity,the transverse ferromagnetic field,the thermal radiation,the nanoparticles shape factors,the peristaltic amplitude ratio,and the concentration of the AuNPs are interacted and analyzed for the gold-blood circulation in the inclined tube.The appropriate model for the thermal conductivity of the nanofluid is chosen to be the effective Hamilton-Crosser model.The undertaken nanofluid can be treated as incompressible non-Newtonian ferromagnetic fluid.The solutions of the partial differential governing equations of the MHD nanofluid flow are executed by the strategy of perturbation approach under the assumption of long wavelength and low Reynolds number.Graphs for the streamwise velocity distributions,temperature distributions,pressure gradients,pressure drops,and streamlines are presented under the influences of the pertinent properties.The practical implementation of this research finds application in treating cancer through a technique known as photothermal therapy(PTT).The results indicate the control role of the magnetism,the heat generation,the shape factors of the AuNPs,and its concentration on the enhancement of the thermal properties and the streamwise velocity of the nanofluid.The results reveal a marked enhancement in the temperature profiles of the nanofluid,prominently influenced by both the intensified heat source and the heightened volume fractions of the nanoparticles.Furthermore,the platelet shape is regarded as most advantageous for heat conduction owing to its highest effective thermal conductivity.AuNPs proved strong efficiency in delivering and targeting the drug to reach the affected area with tumors.These results offer valuable insights into evaluating the effectiveness of PTT in addressing diverse cancer conditions and regulating their progression. 展开更多
关键词 Peristaltic flow NANOFLUID AuNPs MAGNETISM Shape factor Gravity Heat transfer Porous medium
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Currents from relativistic laser-plasma interaction as a novel metrology for the system stability of high-repetition-rate laser secondary sources 被引量:1
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作者 Michael Ehret Iuliana-Mariana Vladisavlevici +16 位作者 Philip Wykeham Bradford Jakub Cikhardt Evgeny Filippov Jose Luis Henares Rubén Hernández Martín Diego de Luis JoséAntonio Pérez-Hernández Pablo Vicente Tomas Burian Enrique García-García Juan Hernández Cruz Mendez Marta Olivar Ruíz Óscar Varela Maria Dolores Rodríguez Frías João Jorge Santos Giancarlo Gatti 《Matter and Radiation at Extremes》 2025年第2期24-34,共11页
This work demonstrates experimentally the close relation between return currents from relativistic laser-driven target polarization and the quality of the relativistic laser–plasma interaction for laser-driven second... This work demonstrates experimentally the close relation between return currents from relativistic laser-driven target polarization and the quality of the relativistic laser–plasma interaction for laser-driven secondary sources,taking as an example ion acceleration by target normal sheath acceleration.The Pearson linear correlation of maximum return current amplitude and proton spectrum cutoff energy is found to be in the range from~0.70 to 0.94.kA-scale return currents rise in all interaction schemes where targets of any kind are charged by escaping laser-accelerated relativistic electrons.Their precise measurement is demonstrated using an inductive scheme that allows operation at high repetition rates.Thus,return currents can be used as a metrological online tool for the optimization of many laser-driven secondary sources and for diagnosing their stability.In particular,in two parametric studies of laser-driven ion acceleration,we carry out a noninvasive online measurement of return currents in a tape target system irradiated by the 1 PW VEGA-3 laser at Centro de Láseres Pulsados:first the size of the irradiated area is varied at best compression of the laser pulse;second,the pulse duration is varied by means of induced group delay dispersion at best focus.This work paves the way to the development of feedback systems that operate at the high repetition rates of PW-class lasers. 展开更多
关键词 relativistic laser plasma interaction pearson linear correlation proton spectrum cutoff energy interaction schemes ion acceleration target normal sheath accelerationthe return current return currents
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Climatic, topographic, and local-scale variables differently shape bird communities in urban streets and parks 被引量:1
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作者 Lucas M.Leveau 《Avian Research》 2025年第3期303-310,共8页
Green cover and human disturbance are important local factors shaping urban bird communities, while climatic and topographic variables can be important when analyzing cities in different biomes. However, the roles of ... Green cover and human disturbance are important local factors shaping urban bird communities, while climatic and topographic variables can be important when analyzing cities in different biomes. However, the roles of large-scale and local variables influencing bird species composition have been scarcely explored in urban areas. This study aimed to analyze the association of climatic, topographic, landscape, and local variables with bird species composition in streets dominated by buildings and urban parks. I expected park bird composition to be more related to large-scale variables, whereas bird species in streets to be more associated with local-scale variables. Bird surveys were conducted in nine cities along a climatic and topographic gradient. Bird species composition in urban parks and streets were related to climatic and topographic variables, local vegetation greenness, and distance to non-urban areas. However, bird composition in streets was also related to noise and pedestrian traffic. The classification of bird composition in urban parks aligned with the phytogeographic provinces, whereas the streets’ bird composition was unrelated to phytogeographic provinces. The results showed that urban habitats with increased vegetation cover allow the colonization of native bird communities and are more aligned with natural large-scale environmental gradients. In contrast, more urbanized sites are decoupled from climatic and topographic gradients and invaded by exotic and widespread native species. 展开更多
关键词 AVIAN Biogeographic Classification Indicator species MACROECOLOGY URBANIZATION
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Complementary roles of glial cells in generating region-specific neuroinflammatory responses and phagocytosis in Parkinson’s disease
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作者 Leyre Ayerra Maria S.Aymerich 《Neural Regeneration Research》 SCIE CAS 2025年第10期2917-2918,共2页
Neuroinflammation is associated with Parkinson’s disease:Reactive gliosis and neuroinflammation are hallmarks of Parkinson’s disease(PD),a multisystem neurodegenerative disorder characterized by a progressive loss o... Neuroinflammation is associated with Parkinson’s disease:Reactive gliosis and neuroinflammation are hallmarks of Parkinson’s disease(PD),a multisystem neurodegenerative disorder characterized by a progressive loss of dopaminergic neurons.Neuroinflammation has long been considered a mere consequence of neuronal loss,but whether it promotes PD or is a key player in disease progression remains to be determined.Human leukocyte antigen. 展开更多
关键词 inflammation LEUKOCYTE generating
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De novo arthropathy following glucocorticoid treatment for severe alcohol-associated hepatitis:Five case reports
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作者 Queralt Herms Sonia Torres +2 位作者 Patrick S Kamath Jordi Gratacós-Ginès Elisa Pose 《World Journal of Hepatology》 2025年第12期254-262,共9页
BACKGROUND Glucocorticoids(GC)are the cornerstone in the treatment of severe alcoholassociated hepatitis(SAH)but may be associated with adverse events.CASE SUMMARY We report a prospective series of patients with SAH w... BACKGROUND Glucocorticoids(GC)are the cornerstone in the treatment of severe alcoholassociated hepatitis(SAH)but may be associated with adverse events.CASE SUMMARY We report a prospective series of patients with SAH who were treated with GC and developed de novo arthropathy within 2 weeks of GC cessation.Five patients were included in this series,three of whom were women.All patients underwent ultrasound evaluation and were referred to the Rheumatology Clinics.Final diagnoses were:Arthralgia associated with GC cessation(n=3),polymyalgia rheumatica(n=1)and psoriatic arthritis(n=1).Joint soreness was the main symptom,whereas arthritis occurred rarely.Patients with arthralgia associated with GC cessation required longer regimes of GC and tapering strategies but remained free of symptoms and specific treatment in the long term.CONCLUSION De novo arthropathy may occur following GC for SAH.Close monitoring and tapering regimes are advised. 展开更多
关键词 CORTICOSTEROIDS Alcohol-related ARTHRALGIA Withdrawal syndrome CIRRHOSIS Joints Case report
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Space and time estimates of second gradient thermal problems
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作者 J.R.FERNÁNDEZ V.PATA R.QUINTANILLA 《Applied Mathematics and Mechanics(English Edition)》 2025年第7期1403-1416,共14页
We consider the space and time decays of certain problems within the second gradient thermal law.Notably,for this thermal theory,the exponential time decay is precluded.First,the time estimates of polynomial type are ... We consider the space and time decays of certain problems within the second gradient thermal law.Notably,for this thermal theory,the exponential time decay is precluded.First,the time estimates of polynomial type are obtained for both the thermal equation and the one-dimensional thermoelastic system,where the impossibility of localization with respect to time is also established.Then,the space estimates are deduced for the multidimensional thermoelastic problem,which allow to show the exponential decay of the energy. 展开更多
关键词 second gradient theory THERMOELASTICITY spatial estimate polynomial decay
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Split gauge-boson mass in SU(N)×SU(M)theories
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作者 Julia Gómez Concejo Felipe J.Llanes-Estrada +1 位作者 Diego María-Almazán Alexandre Salas-Bernárdez 《Communications in Theoretical Physics》 2025年第9期61-71,共11页
We extend a well-known mass-gap equation for pure gluodynamics in global colour models(formulated in equal-time quantization in Coulomb gauge)to one in which gluons are split into two sets,each exhibiting different ma... We extend a well-known mass-gap equation for pure gluodynamics in global colour models(formulated in equal-time quantization in Coulomb gauge)to one in which gluons are split into two sets,each exhibiting different masses.If the theory is SU(N)×SU(M)with gluons in both groups having identical couplings(as suggested by Grand Unification arguments at large scales)it is immediate to see that different masses are generated for each subgroup.This global symmetry is not broken,but the split masses erase accidental symmetries that might be present due to the two couplings being the same at a large scale,such as SU(N×M)or similar.We also numerically explore a couple of low-dimensional examples of simple Lie groups,but in spite of the system of equations having a form that would seem to allow spontaneous symmetry breaking,it is not triggered for these groups whose algebra has no ideal,and the dispersion relations for the various gluons converge to the same form. 展开更多
关键词 global symmetry breaking gap equation CHROMODYNAMICS hamiltonian QCD
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Phenotypic and genetic differentiation between two chromosomal taxa of the gastropod Nucella lapillus at Galician rocky shores(NW Spain)
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作者 Daniel García-Souto Jonathan Fernández-Rodríguez +2 位作者 Juan J.Pasantes Emilio Rolán-Alvarez Juan Galindo 《Current Zoology》 2025年第6期733-744,共12页
In certain North Atlantic rocky shores,2 chromosomal lineages of Nucella lapillus have been observed at different extremes of an environmental gradient.Here,we have determined the presence of this chromosomal polymorp... In certain North Atlantic rocky shores,2 chromosomal lineages of Nucella lapillus have been observed at different extremes of an environmental gradient.Here,we have determined the presence of this chromosomal polymorphism,resulting from Robertsonian translocations,in populations of the Iberian Peninsula spanning a similar gradient.Interestingly,we have found monomorphic populations(2n=26)across the gradient while we only found polymorphic populations(2n=27-36)in certain exposed microhabitats,and never both types of populations together.These chromosomal lineages differ morphologically and genetically in a manner that can be successfully discriminated,based on their morphology(95%of success)and molecular variation(99.9% of success),in the studied set of samples,and so considering these data this could potentially represent isolated evolutionary lineages or taxa.This situation is discussed in relation to the data available in previous studies in this and other geographical areas for this species.The new findings do not solve the problem of the Robertsonian polymorphism known to exist in this species,but it could perhaps suggest a new approach to solve it,suggesting a wide geographical comparison between the 2 taxa to confirm if they represent evolutionary isolated lineages or maintain a certain degree of hybridization. 展开更多
关键词 AFLPS chromosomal races CYTOGENETICS evolution morphology Nucella lapillus
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Behavior and survival of parasitic Shiny Cowbird(Molothrus bonariensis)fledglings
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作者 Ignacio Crudele Bruno Riovitti +1 位作者 Juan C.Reboreda Vanina D.Fiorini 《Current Zoology》 2025年第5期613-619,共7页
For songbirds,the post-fledging period is critical for development and survival,as young must learn to get food,practice flying,and identify predators to become independent from their parents and disperse or migrate.O... For songbirds,the post-fledging period is critical for development and survival,as young must learn to get food,practice flying,and identify predators to become independent from their parents and disperse or migrate.Obligate avian brood parasites,like cuckoos and cowbirds,lay eggs in nests of other bird species that provide parental care until the parasite’s young become independent.The information on the post-fledging period in songbirds is limited due to the difficulty in following and observing fledglings and it is even scarcer for brood parasites.We studied the behavior,survival,and age of independence of Shiny Cowbird(Molothrus bonariensis)fledglings raised by 2 hosts that differ markedly in body size:the House Wren(Troglodytes aedon)and the Chalk-Browed Mockingbird(Mimus saturninus).We radio-tracked individuals from a few days before they left the nest until they disappeared from the natal territory.We found:(1)chicks left the nest when they were 11-15 days of age and the age of fledgling did not differ between the 2 host species,(2)after leaving the nest,they spent most of the time perched in a hidden place without begging but as they grew,the proportion of time perched without begging decreased and begging in hidden and exposed places increased,(3)we observed approaches between adult parasitic females and young in host territories,(4)young abandoned the host territory and joined conspecific flocks when they were 35-39 days of age,and(5)the estimated post-fledging survival was between 12.5%and 20.8%. 展开更多
关键词 Avian brood parasitism Conspecific recognition Juvenile dispersal Molothrus bonariensis RADIOTELEMETRY Shiny Cowbird
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Intraslab seismicity characteristics of northern Chile
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作者 Zixin Chen Lei Gao +3 位作者 Haijiang Zhang Shaobo Yang Ying Liu Diana Comte 《Earthquake Science》 2025年第4期273-287,共15页
The Chilean subduction zone is one of the most seismically active regions globally,characterized by extensive intermediatedepth seismicity in the slab.In this study,we construct a new earthquake catalog for northern C... The Chilean subduction zone is one of the most seismically active regions globally,characterized by extensive intermediatedepth seismicity in the slab.In this study,we construct a new earthquake catalog for northern Chile using seismic waveforms assembled for the period of 2014-2019,from which 320,070 P-wave and 232,907 S-wave first arrivals are obtained for 25,763 earthquakes.Grid search location method NonLinLoc is applied to determine initial earthquake locations and double-difference location method is used to improve relative event locations.The distribution of earthquakes exhibits distinct patterns to the north and south of 21°S.There are many more earthquakes deeper than~150 km to the south of 21°S,while relatively fewer to the north.The intraslab earthquakes shallower than~80 km generally reveal a distinct double seismic zone,and the gap between the two seismic planes disappears at a depth of approximately~80 km,followed by a concentration of seismicity in the depth range of~80-150 km.In the deeper slab,there exist several seismicity clusters with distinct earthquake activities down to~300 km.These characteristics shown in slab seismicity are likely caused by different mechanisms and can be helpful for understanding the subduction process. 展开更多
关键词 seismic location Chile subduction zone double seismic zone deep seismicity cluster
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THE GLOBAL DYNAMICS OF A 3-DIMENSIONAL DIFFERENTIAL SYSTEM IN R^(3) VIA A DARBOUX INVARIANT
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作者 Jaume LLIBRE Claudia VALLS 《Acta Mathematica Scientia》 2025年第2期338-346,共9页
The differential system ẋ=ax−yz,ẏ=−by+xz,ż=−cz+x^(2),where a,b and c are positive real parameters,has been studied numerically due to the big variety of strange attractors that it can exhibit.This system has a Darboux... The differential system ẋ=ax−yz,ẏ=−by+xz,ż=−cz+x^(2),where a,b and c are positive real parameters,has been studied numerically due to the big variety of strange attractors that it can exhibit.This system has a Darboux invariant when c=2b.Using this invariant and the Poincarécompactification technique we describe analytically its global dynamics. 展开更多
关键词 INVARIANT Poincare ball Poincarédisc w-limit Q-limit differential system in R^(3)
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Semi Analytical Solution of MHD and Heat Transfer of Couple Stress Fluid over a Stretching Sheet with Radiation in Porous Medium
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作者 Sara I.Abdelsalam M.Khairy +2 位作者 W.Abbas Ahmed M.Megahed M.S.Emam 《Frontiers in Heat and Mass Transfer》 2025年第6期1833-1846,共14页
This comprehensive research examines the dynamics of magnetohydrodynamic(MHD)flow and heat transfer within a couple stress fluid.The investigation specifically focuses on the fluid’s behavior over a vertical stretchi... This comprehensive research examines the dynamics of magnetohydrodynamic(MHD)flow and heat transfer within a couple stress fluid.The investigation specifically focuses on the fluid’s behavior over a vertical stretching sheet embedded within a porous medium,providing valuable insights into the complex interactions between fluid mechanics,thermal transport,and magnetic fields.This study accounts for the significant impact of heat generation and thermal radiation,crucial factors for enhancing heat transfer efficiency in various industrial and technological contexts.The research employs mathematical techniques to simplify complex partial differential equations(PDEs)governing fluid flow and heat transfer.Specifically,suitable similarity transformations are applied to convert the PDEs into a more manageable system of ordinary differential equations(ODEs).The homotopy perturbation method(HPM)is employed to derive approximate analytical solutions for the problem.The influences of key parameters,such as magnetic field strength,heat generation,thermal radiation,porosity,and couple stress,on velocity and temperature profiles are analyzed and discussed.Findings indicate that the mixed convection parameter positively affects flow velocity,while the magnetic field parameter significantly alters the flow dynamics,exhibiting an inverse relationship.Further,this type of flow behavior model is relevant to real-world systems like cooling of nuclear reactors and oil extraction through porous formations,where magnetic and thermal effects are significant. 展开更多
关键词 Couple stress fluid HPM MHD non-newtonian fluid heat transfer stretched sheet thermal radiation
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Artificial neural network validation of MHD natural bioconvection in a square enclosure:entropic analysis and optimization
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作者 Noura Alsedais Mohamed Ahmed Mansour +1 位作者 Abdelraheem Mahmoud Aly Sara I.Abdelsalam 《Acta Mechanica Sinica》 2025年第9期17-35,共19页
This study numerically investigates inclined magneto-hydrodynamic natural convection in a porous cavity filled with nanofluid containing gyrotactic microorganisms.The governing equations are nondimensionalized and sol... This study numerically investigates inclined magneto-hydrodynamic natural convection in a porous cavity filled with nanofluid containing gyrotactic microorganisms.The governing equations are nondimensionalized and solved using the finite volume method.The simulations examine the impact of key parameters such as heat source length and position,Peclet number,porosity,and heat generation/absorption on flow patterns,temperature distribution,concentration profiles,and microorganism rotation.Results indicate that extending the heat source length enhances convective currents and heat transfer efficiency,while optimizing the heat source position reduces entropy generation.Higher Peclet numbers amplify convective currents and microorganism distribution complexity.Variations in porosity and heat generation/absorption significantly influence flow dynamics.Additionally,the artificial neural network model reliably predicts the mean Nusselt and Sherwood numbers(Nu&Sh),demonstrating its effectiveness for such analyses.The simulation results reveal that increasing the heat source length significantly enhances heat transfer,as evidenced by a 15%increase in the mean Nusselt number. 展开更多
关键词 Artificial neural network Gyrotactic microorganisms MAGNETOHYDRODYNAMICS Natural convection Square enclosure
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Joint inversion of body wave arrival times and surface wave dispersion data for the subduction zone velocity structure of central Chile
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作者 ZiXin Chen HaiJiang Zhang +3 位作者 Lei Gao Ying Liu ShaoBo Yang Diana Comte 《Earth and Planetary Physics》 2025年第5期1048-1060,共13页
The Chilean Pampean flat slab subduction segment is characterized by the nearly horizontal subduction of the Nazca Plate within the depth range of 100-120 km.Numerous seismic tomography studies have been conducted to ... The Chilean Pampean flat slab subduction segment is characterized by the nearly horizontal subduction of the Nazca Plate within the depth range of 100-120 km.Numerous seismic tomography studies have been conducted to investigate its velocity structure;however,they have used only seismic body wave data or surface wave data.As a result,the existing velocity models in the region may have relatively large uncertainties.In this study,we use body wave arrival times from earthquakes occurring in central Chile between 2014 and 2019,as well as Rayleigh wave phase velocity maps at periods of 5-80 s from ambient noise empirical Green’s functions in Chile.By jointly using body wave arrival times and surface wave dispersion data,we refine the VS model and improve earthquake locations in the central Chile subduction zone.Compared with previous velocity models,our velocity model better reveals an eastward-dipping high-velocity plate representing the subducting Nazca Plate,which is 40-50 km thick and is more consistent with the slab thickness estimated by receiver function imaging and thermal modeling.Overall,the intraslab seismicity distribution spatially correlates well with the slab high-velocity anomalies except along the subduction paths of the CopiapóRidge and Juan Fernández Ridge.Additionally,parallel low-velocity stripes are imaged beneath the subducting plate,which are likely associated with the accumulated melts.The joint inversion velocity model also resolves widespread low-velocity anomalies in the crust beneath the Central Volcanic Zone of the central Andes,likely representing crustal magma chambers for various volcanoes. 展开更多
关键词 Chilean Pampean flat slab seismic joint inversion seismic velocity model Central Volcanic Zone of the central Andes CopiapóRidge Juan Fernández Ridge
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