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Study of asphaltene reaggregation in toluene/heptane mixture by dynamic and static light scattering

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Petroleum Research 2024年第1期9卷 48-54页

作者： vladimir n.Kuryakov Oil and Gas Research Institute of RAS(OGRI RAS) Gubkina Str.3119333MoscowRussian Federation

This paper presents the study of the effect of multiple ultrasonic impacts on submicron asphaltene aggregates in a toluene/heptane solution,conducted with dynamic light scattering *** objects of the study were four samples of asphaltenes obtained from four different *** all samples,the change in the average size of the asphaltene submicron aggregates with time was measured after the addition of a precipitant(heptane)to a solution of asphaltenes in toluene at an amount above the threshold *** aggregates formed in solution after the addition of the precipitant and were subjected to ultrasonic treatment,which led to the destruction of the asphaltene *** of destroyed asphaltenes was *** kinetics of this aggregation were similar to the kinetics of aggregation of asphaltenes after the addition of a *** iterations of asphaltene aggregate destruction in the sample led to a significant change in the kinetics of aggregation:the growth of aggregates slowed and stabilized at a size of approximately 200 nm and 30 nm for the different studied samples.

关键词： Asphaltenes Aggregation Sonication Dynamic light scattering Re-aggregation Colloidal stability Resins

Enhanced saturation magnetization in La^(3+) doped niCo ferrites prepared by sol-gel auto-combustion method

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Journal of Rare Earths 2024年第8期42卷 1546-1554,I0005页

作者： Maddileti Jelli vidyasagar Thopudurthy Krishna Reddy C.v. Department of Physics Rayalaseema UniversityKurnoolA.P518007.Iindia Department of Physics Govermment PolytechnicRayachotiA.P516269India

Lanthanum doped nickel-cobalt nano ferrites with chemical formula ni_(0.5)Co_(0.5)LaxFe_(2-x)O_(4)(x=0.05,0,10,0.15 and 0,20) were prepared using a simple sol-gel auto combustion *** basic structural properties were determined by X-ray diffraction method and the formation of single phased spinel ferrite was *** crystalline size decreased from 25 to 11 nm and lattice parameter a increases with increase of La *** surface morphology of these ferrites was observed by field-emission scanning electron microscopy(FESEM) and agglomerated irregular grains are observed with increase of the rare earth element La ***-dispersive X-ray spectroscopy(EDX) result confirms the presence of the required *** Fourier transform infrared spectroscopy(FTIR) spectrum indicates the formation of the spinel ferrite structure with M-O *** direct band measurements from ultraviolet-visible spectroscopy(Uv-vis) spectroscopy indicate that the direct band gap decreases from 1.39 to 1.19 ev for x=0.05 to x=0.15,then increases to 1.28 ev for x=*** room temperature magnetic properties of these ferrites were studied by a vibrating sample magnetometer(vSM).The enhanced saturation magnetization of 49.73 emu/g is observed for x=0.10 and then saturation magnetizations are gradually decreased for x=0.15 and x=*** the remanent magnetization and coercivity also follow the same trend.

关键词： Ferrites Sol-gel auto combustion La doping Magnetic properties Rare earths

Heterosis effect for larval performance of fall armyworm interstrain hybrids

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Insect Science 2024年第4期31卷 1296-1312页

作者： Laijiao Lan nicolas nègre DGIMI University of MontpellierINRAEMontpellierFrance

Spodoptera frugiperda,also known as fall armyworm(FAW),is an invasive crop pest that can feed on a variety of host plants,posing a serious threat to food *** are two sympatric strains of FAW that are morphologically identical but described with different food preferences:the“rice strain”(SfR)and the“corn strain”(SfC).A few genetic loci exist to identify these two *** and Z-chromosome-linked haplotypes are the most used,but the biggest part of the genome displays little polymorphism between strains that could explain their adaptation to different *** have previously observed consistent transcription differences between the strains in both laboratory and natural ***,we wonder if there are effects from host-strain-associated loci,maternally or paternally inherited,on FAW performance that could explain the divergence between the two FAW *** test this hypothesis,we first produced two F1 hybrid generations(SfR♀×SfC♂,SfC♀×SfR♂).These reciprocal hybrids should be heterozygous for all chromosomes except for the maternally inherited mitochondrial and sexual W *** evaluate whether plant preference is determined by these genetic loci,we cultivated the two hybrids and the two parental strains in triplicate on an artificial diet and recorded several phenotypic traits such as weight over time,survival rate,emerging rate,developmental time,and sex ***,the same performance experiment was carried out on corn ***,on the artificial diet,the two hybrid genotypes were both more performant than the two parental strains in terms of survival rate,pupal emerging rate,and developmental time,whereas they were intermediate to the inbred parental strains in pupal *** the corn plant diet,both hybrid genotypes outperformed the two parental strains in larval *** these asymmetrical results revealed that mitochondrial or sex-linked haplotypes alone cannot explain the performance differences

关键词： fall armyworm Haldane's rule heterosis hybrid performance mitochondria

Kuedinskie Kluchiki, a Unique Middle Permian Biota Locality as a Key-point for Reconstruction of Late Paleozoic Terrestrial Ecosystems of the Urals, Russia

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 850-866页

作者： Serge v.nAUGOLnYKH Geological Institute of Russian Academy of Sciences Pyzhevsky per.7119017 MoscowRussia

Field work focused on the Kuedinskie Kluchiki locality, Perm region, Urals, Russia, which contains a rich assemblage of diverse fossil organisms including higher plants(equisetophytes, pteridosperms, ginkgophytes, conifers, vojnovskyans) represented by stems, leaves and reproductive organs;invertebrates(mollusks, arthropods), and tetrapods(temnospondyl amphibians, seymouriamorphs, cotylosaurs, synapsids, diapsids), as well as bony fishes. General characteristics of the taxonomical composition of the Kuedinskie Kluchiki locality are given. A new peltaspermalean pteridosperm taxon, Compsopteris longipinnata sp. nov., and a voltzialean conifer Archaeovoltzia kuedensis sp. nov. are described. General considerations on the paleoecologic and paleogeographic conditions of the Kuedinskie Kluchiki locality origin are given.

关键词： paleobotany paleoecology taxonomy Lagerst?tten new taxa peltasperms conifers Wordian Cis-Urals

A FLEXIBLE OBJECTIvE-COnSTRAInT APPROACH AnD A nEW ALGORITHM FOR COnSTRUCTInG THE PARETO FROnT OF MULTIOBJECTIvE OPTIMIZATIOn PROBLEMS

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Acta Mathematica Scientia 2024年第2期44卷 702-720页

作者： n.HOSEInPOOR M.GHAZnAvI Faculty of Mathematical Sciences Shahrood University of TechnologyShahroodIran

In this article, a novel scalarization technique, called the improved objective-constraint approach, is introduced to find efficient solutions of a given multiobjective programming problem. The presented scalarized problem extends the objective-constraint problem. It is demonstrated that how adding variables to the scalarized problem, can lead to find conditions for (weakly, properly) Pareto optimal solutions. Applying the obtained necessary and sufficient conditions, two algorithms for generating the Pareto front approximation of bi-objective and three-objective programming problems are designed. These algorithms are easy to implement and can achieve an even approximation of (weakly, properly) Pareto optimal solutions. These algorithms can be generalized for optimization problems with more than three criterion functions, too. The effectiveness and capability of the algorithms are demonstrated in test problems.

关键词： multiobjective optimization Pareto front scalarization objective-constraint approach proper efficient solution

Proximity to corridors benefits bird communities in vegetated interrow vineyards in Mendoza, Argentina

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Avian Research 2024年第2期15卷 147-155页

作者： Andrea Paula Goijman Agustín Zarco EEA La Consulta Instituto Nacional de Tecnología Agropecuaria(INTA)San CarlosMendozaArgentina Instituto Argentino de Investigacion en las Zonas Aridas(IADIZA)COnICET 5500MendozaArgentina

Management under ecological schemes and increasing habitat heterogeneity,are essential for enhancing biodiversity in *** provide several contributions to agriculture,for example pest control,recreation and enhancing human mental health,and have intrinsic *** are also ideal model organisms because they are easy to survey,and species respond differently to agricultural land use at different *** borders of crops are key for many species of birds,and distance to the border have been found to be an important factor in vineyard-dominated *** evaluate if there are differences in the bird assemblage,between the interior compared to borders within vineyards,using a hierarchical community occupancy *** hypoth-esized that occupancy of birds is greater in environments with greater heterogeneity,which in this study was considered to be contributed by the proximity to vegetated *** expected that vineyard borders close to corridors will have higher bird occupancy than the center of the *** research was conducted in three vineyards with biodiversity-friendly management practices,in Gualtallary,Mendoza,*** surveys were conducted over three breeding seasons from 2018 to *** and richness of the bird community was more closely associated with the borders adjacent to the corridors than with the interior of the vineyards,as we initially predicted,although the assemblage of birds did not differ *** than 75%of the registered species consume exclusively or partially ***-friendly management and ecological schemes,together with vegetated corridors provide multiple benefits for biodiversity *** ap-proaches not only minimize the use of agrochemicals but also prioritize soil cover with spontaneous vegetation,which supports a diverse community of insectivorous bird species,potentially contributing to pest control.

关键词： Avian Bayesian analysis Field scale agroecosystem Management Multi-species occupancy model nature’s contributions to people

Bio-Inspired Intelligent Routing in WSn: Integrating Mayfly Optimization and Enhanced Ant Colony Optimization for Energy-Efficient Cluster Formation and Maintenance

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 127-150页

作者： v.G.Saranya S.Karthik Department of Electronics and Communication Engineering Faculty of Engineering&TechnologySRM Institute of Science and TechnologyVadapalani CampusChennai600026India

Wireless Sensor networks(WSns)are a collection of sensor nodes distributed in space and connected through wireless *** sensor nodes gather and store data about the real world around ***,the nodes that are dependent on batteries will ultimately suffer an energy loss with time,which affects the lifetime of the *** research proposes to achieve its primary goal by reducing energy consumption and increasing the network’s lifetime and *** present technique employs the hybrid Mayfly Optimization Algorithm-Enhanced Ant Colony Optimization(MFOA-EACO),where the Mayfly Optimization Algorithm(MFOA)is used to select the best cluster head(CH)from a set of nodes,and the Enhanced Ant Colony Optimization(EACO)technique is used to determine an optimal route between the cluster head and base *** performance evaluation of our suggested hybrid approach is based on many parameters,including the number of active and dead nodes,node degree,distance,and energy *** objective is to integrate MFOA-EACO to enhance energy efficiency and extend the network life of the WSn in the *** proposed method outcomes proved to be better than traditional approaches such as Hybrid Squirrel-Flying Fox Optimization Algorithm(HSFLBOA),Hybrid Social Reindeer Optimization and Differential Evolution-Firefly Algorithm(HSRODE-FFA),Social Spider Distance Sensitive-Iterative Antlion Butterfly Cockroach Algorithm(SADSS-IABCA),and Energy Efficient Clustering Hierarchy Strategy-Improved Social Spider Algorithm Differential Evolution(EECHS-ISSADE).

关键词： Enhanced ant colony optimization mayfly optimization algorithm wireless sensor networks cluster head base station(BS)

Wormhole solutions under the effect of dark matter in f(R,L_(m))gravity

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Communications in Theoretical Physics 2024年第5期76卷 102-113页

作者： Lakhan v Jaybhaye Moreshwar Tayde PK Sahoo Department of Mathematics Birla Institute of Technology and Science-PilaniHyderabad CampusHyderabad-500078India

In the background of f(R,L_(m))gravity,this work investigates three distinct dark matter halo profiles to test the possibility of generalised wormhole geometry within the galactic halo *** current study aims to accomplish these goals by examining various dark matter profiles including universal rotation curves(URC),navarro-Frenk-White(nFW)model-Ⅰ,and nFW model-Ⅱinside two distinct f(R,L_(m))gravity *** to the f(R,L_(m))=R/2+L^(a)_(m)model,the dark matter(DM)halo density profiles produce suitable shape functions that meet all the necessary requirements for exhibiting the wormhole geometries with appropriate choice of free *** addition,to examine DM profiles under the f(R,L_(m))=R/2+(1+λR)L_(m) model,we consider a specific shape ***,we observed that the derived solution from both two models violates the null energy constraints,confirming that the DM supports wormholes to maintain in the galactic halo.

关键词： f(R L_(m))gravity wormhole dark matter(Some figures may appear in colour only in the online journal)

Magnetic resonance imaging-guided focused ultrasound thalamotomy launch with remote telemedicine international proctorship

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Chronic Diseases and Translational Medicine 2024年第1期10卷 40-50页

作者： Igor v.Buzaev Rezida M.Galimova Dinara I.nabiullina Sergey n.Illarioshkin naufal Sh.Zagidullin Shamil M.Safin Department of Surgery Bashkir State Medical UniversityUfaRussia Intelligent neurosurgery Clinic Ltd.International Medical Center V.S.Buzaev memorialUfaRussia Directorate Research Center of NeurologyVolokolamskoye ShosseMoscowRussia

Background: COvID-19 limitations have hindered the implementation of new technologies by preventing proctors from coming to the *** share our first experience of magnetic resonance imaging(MRI)-guided focused ultrasound(MRgFUS)treatment with an international remote online proctorship,and develop and evaluate the methodology of remote MRgFUS ***: This single-center,nonrandomized controlled prospective study included 94 patients:27 with essential tremor(ET)and 67 with tremor-dominant Parkinson's disease(PD).The coming of proctors was impossible,so we arranged for the remote participation of proctors from the United Kingdom,Spain,and Israel.A total of 38 patients(40.4%)received telemedicine-proctored treatment(proctor group)and 56 received their treatment independently(solo group).We used the Clinical Rating Scale for Tremor(CRST)for ET patients and the Unified Parkinson's Disease Rating Scale(UPDRS)Part III for PD ***: In patients with ET,success rates were 81.8%(proctor group)and 100%(solo group)(p=0.22).CRST reduction on the treated side was 71.43%[65.83%;80.56%](proctor group)versus 60.87%[53.99;79.58](solo group)(p=0.19).none of the patients showed worsening of tremors within 1 *** patients with PD,the success rates were 92.6%(proctor group)and 100%(solo group)(p=0.08).The UPDRS Part III improvement was 30.1%(proctor group)versus 39.9%(solo group)(p=0.003).The 1-year recurrence rate was 40%(proctor group)and 17.5%(solo group)(p=0.04).no complications were observed at 6 ***: We developed a feasible and safe methodology for telemedicine remote online-proctored MRgFUS *** significant difference was observed between the solo and developed remote proctor protocols in terms of complication rate,effect,and long-term results;however,UPDRS Part III improvement was better in the PD solo *** study demonstrated that the MRgFUS international proctorship can be performed successfully remotely.

关键词： essential tremor MRgFUS Parkinson's disease proctor telemedicine