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On B(5,20)2-Groups

Al.ebra Colloquium 2024年第3期31卷 429-440页

作者： e.A.Alhassan Y.l.Tan Y.li School of Mathematical Sciences Jiangsu UniversityZhenjiangJiangsu 212013China Department of Mathematics Brock UniversitySt.CatharinesOntario L2S 3A1Canada

A finite group G is said to be a B(n,k)group if for any n-element subset[a_(1),…,a_(n)]of G,|{a_(i)a_(j)|1≤i,j≤n}|≤*** is of interest to characterize the structure of B(n,k)groups for n(n+1)/2≤k≤n^(2)-*** B(5,k)groups for 15≤k≤19 have been investigated by several *** this paper,we give a complete characterization of B(5,20)2-groups by showing there are five classes of such groups which are nontrivial and nonabelian.

关键词： B(n,k)groups small squaring property central.extension GAP

Feeding behavior and hormoligosis associated with imidacloprid resistance in Asian citrus psyllid,Diaphorina citri

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Insect Science 2024年第4期31卷 1211-1221页

作者： Xue dong Chen Justin George lauren M.Diepenbrock Hunter Gossett Guoping liu Jawwad A.Qureshi lukasz l.Stelinski entomology and Nematology Department University of FloridaCitrus Research and Education CenterLake AlfredFloridaUSA Southern Insect Management Research Unit USDA-ARSStonevilleMississippiUSA entomology and Nematology Department University of FloridaSouthwest Florida Research and Education CenterImmokaleeFloridaUSA

Imidacloprid is a neonicotinoid insecticide used for managing the Asian citrus psyllid,Diaphorina citri Kuwayama,which serves as vector of phytopathogens causing citrus ***,development of resistance to neonicotinoids among populations of *** has coincided with occasional control failures in the *** objectives of this research were to(1)survey current levels of imidacloprid resistance in Florida citrus;(2)compare feeding behavior between imidacloprid-resistant and susceptible *** using electrical penetration graph recordings,and(3)investigate the possible amplification of insecticide hormoligosis associated with *** surveys confirmed that the susceptibility of *** populations to imidacloprid has decreased in commercial Florida citrus groves compared with a laboratory-susceptible *** 12 generations of selection,resistance to imidacloprid increased by 438 fold compared with the susceptible ***-susceptible *** feeding on citrus exhibited significantly more bouts associated with intercellular pathway(C),phl.em penetration(D),phl.em salivation(e1),and nonprobing(Np)activities than imidacloprid-resistant ***,there were no differences observed in the frequency or duration of phl.em ingestion or xylem feeding between susceptible and resistant *** was no statistical difference in fecundity between resistant and susceptible ***,the fecundity of imidacloprid-susceptible female *** treated with a sublethal concentration of imidacloprid(lC_(25))increased significantly compared with controls,while such hormoligosis was less pronounced among imidacloprid-resistant *** results suggest that imidacloprid-resistant psyllids may cease feeding sooner than susceptible counterparts following sublethal.exposure to this insecticide,indicative of a behavioral resistance mechanism.

关键词： artificial selection electrical penetration graph feeding behavior hormoligosis insecticide resistance sublethal.exposure

When Fl.eing Matters:Differences in escape Behaviours of Three Northeast Asian Anurans

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Asian Herpetological Research 2024年第1期15卷 41-48页

作者： Yoonjung YI Zoljargal PUReVDORJ Irina MASlOVA Yikweon JANG Amaël BORZÉe laboratory of Animal Behaviour and Conservation College of Life SciencesNanjing Forestry UniversityNanjing 210037JiangsuChina Division of ecoScience and Department of life Sciences Ewha Womans UniversitySeoul 03760Republic of Korea Department of Biology School of MathematicsMongolian State University of EducationUlaanbaatar 210648Mongolia Department of Forest and environmental Resources Chungnam National UniversityDaejeon 34134Republic of Korea Federal Scientific Center of the east Asia Terrestrial Biodiversity Far Eastern Branch of Russian Academy of SciencesVladivostok 690022Russia

Prey species may have their own optimal.escape strategy to balance predation risks and the energetic cost of *** species have an advantage when maintaining a short fl.eing distance,while others may favour an earl.er escape based on microhabitat,size,or body ***,we examined the escape behaviour of the three syntopic Northeast Asian anuran species:Mongolian toads(Strauchbufo raddei),Amur brown frogs(Rana amurensis),and Japanese treefrogs(Dryophytes japonicus)in Mongolia,Russia,China and DPR *** examined flight initiation distance(FID;the distance from a potential predator to the point when the individual starts to fl.e)and distance fled(DF;distance between flight initiation and flight termination points)of each species and the effects of microhabitat,sex,and body *** raddei and *** had a longer FID than ***,and *** also had a longer DF than *** trends remained similar when dividing FID and DF by a size proxy(snout-vent length)for all *** suggests that the treefrog *** used a strategy to stay immobile even when they were detected,and the toad *** reacted quicker and more sensitively to predators despite the presence of *** *** had a significantly longer FID than males suggesting that females are more sensitive to predation risk in this species,but body size was not significant for any of the three *** results indicate that the three sympatric species have different escaping strategies,likely related to differences in physiology and crypticity.

关键词： amphibian distance fled escape behaviour flight initiation distance predation

effects of Aging at 550℃ on α'-Martensitic Transformation of High Si-Bearing Metastable Austenitic Stainless Steel Weld Metal

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Acta Metallurgica Sinica(english letters) 2024年第9期37卷 1467-1479页

作者： Yakui Chen Shitong Wei dong Wu Shanping lu Shenyang National laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and engineering University of Science and Technology of ChinaShenyang110016China CAS Key laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

The high Si-bearing 15Cr-9Ni-Nb metastable austenitic stainless steel weld metal was prepared via gas tungsten arc welding and then processed by stabilized heat treatment(SHT)at 850℃ for 3 *** effects of 550℃ aging on the α'-martensitic transformation of the as-wel.ed and the SHT weld metals were *** results showed that the weld metal had poor thermal stability of *** precipitation of NbC during the 850℃ SHT made the thermal stability of the local matrix decrease and led to the formation of a large amount of C-depleted α'-*** precipitation of coarse σ-phase at the δ-ferrite led to the Cr-depleted zone and the formation of Cr-depleted α'-martensite at the early stage of 550℃ *** homogenized diffusion of C and Cr in the matrix during 550℃ aging led to the restoration of austenitic thermal stability and the decrease of α'-martensite *** C-depleted α'-martensite content in the SHT weld metal decreased rapidly at the early stage of aging due to the fast diffusion rate of the C atom in the matrix,while the Cr-depleted α'-martensite decreased at the later stage of aging due to the decreased diffusion rate of the Cr.

关键词： Metastable austenitic stainless steel weld metal α'-martensitic transformation δ-ferrite σ-phase

Performance of evolutionary optimized machine learning for modeling total organic carbon in core samples of shale gas fields

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Petroleum 2024年第1期10卷 150-164页

作者： leonardo Goliatt C.M.Saporetti l.C.Oliveira e.Pereira Department of Computational and Appl.ed Mechanics Federal University of Juiz de ForaJuiz de ForaBrazil Department of Computational Modeling Polytechnic InstituteRio de Janeiro State UniversityNova FriburgoBrazil Petrobras Rio de JaneiroBrazil Department of Stratigraphy and Paleontology Rio de Janeiro State UniversityRio de JaneiroBrazil

Rock samples'TOC content is the best indicator of the organic matter in source *** origin rock samples’analysis is used to calculate it manually by *** method requires time and resources because it rel.es on samples from many well intervals in source ***,research has been done to aid this *** learning algorithms can estimate total organic carbon instead of well logs and stratigraphic *** light of these efforts,the current work present a study on automating the total organic carbon estimation using machine learning approaches improved by an evolutionary methodology to give the model flexibility and *** algorithms,differential.evolution,particle swarm optimization,grey wolf optimization,artificial bee colony,and evolution strategies were used to improve machine learning models to predict *** six metaheuristics were integrated into four machine learning methods:extreme learning machine,elastic net linear model,linear support vector regression,and multivariate adaptive regression *** samples from the Yudong-Nan shale gas field,located in the Sichuan basin,were used to evaluate the hybrid *** findings show that combining machine learning models with an evolutionary algorithms in a hybrid fashion produce flexible models that accurately predict *** results show that,independent of the metaheuristic used to guide the model selection,optimized extreme learning machines attained the best performance scores according to six *** hybrid models can be used in exploratory geological research,particularly for unconventional oil and gas resources.

关键词： Total organic carbon Hybrid models Automated machine learning evolutionary algorithms Geology

Phanerozoic co-evolution of O2-CO2 and ocean habitability

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National Science Review 2024年第6期11卷 18-21页

作者： Zunli lu Rosalind e.M.Rickaby Jonathan l.Payne Ashley N.Prow Department of earth & environmental Sciences Syracuse University Department of earth Sciences University of Oxford Department of earth and Planetary Sciences Stanford University

Atmospheric carbon dioxide and oxygen concentrations are partially linked via the geological cycle of organic carbon （Fig. 1A–C; e.g. CO2+H2O■CH2O+O2）. The history of these two biologically active components, controls on their concentrations, and implications for the complexity of the biosphere and habitability of earth have been hotly debated, but are generally considered independently.

关键词： CO2-CONCeNTRATING MeCHANISM OXYGeN eVOlUTION ANOXIA

exploring the effects of anthropogenic disturbance on predator inspection activity in Trinidadian guppies

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Current Zoology 2024年第1期70卷 109-111页

作者： Alix J.P Brusseau laurence e.A.Feyten Adam l.Crane Grant e.Brown Department of Biology Concordia UniversityMontrealQCH4B 1R6Canada Department of Biomedical Sciences WCVMUniversity of SaskatchewanSaskatoonSKCanada

Prey animals are often faced with uncertainty due to having imperfect information regarding current local conditions,including predation risks and the availability of reliable foraging opportunities(Dall 2010).As this uncertainty increases,the probability of making costly behavioral.errors also increases,leading to more risk averse behavioral tactics(Feyten et al.2019).For example,Trinidadian guppies Poecilia reticulata are far more risk averse when faced with multiple unknown sources of risk assessment information than when faced with a mix of known and unknown cues(Feyten et al.2019).Prey can reduce uncertainty by gathering and integrating private and social information regarding current risk levels within microhabitats(Dall 2010;Munoz and Blumstein 2012).

关键词： human disturbance information availability information reliability predator-prey interactions risk assessment uncertainty

In situ Hydrothermal Oxidation of Ternary FeCoNi Alloy electrode for Overall Water Splitting

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energy & environmental Materials 2024年第2期7卷 161-170页

作者： Yuwei Chen lixia Yang Chao li Yuqiu Wu Xiao lν Hairen Wang Jun'e Qu Key laboratory for the Green Preparation and Application of Functional Materials Hubei Key Laboratory of Polymer MaterialsSchool of Materials Science and EngineeringHubei UniversityWuhan 430062China Faculty of Material science and Chemistry China University of GeosciencesWuhan 430074China

exploring noble metal-free catalyst materials for high efficient electrochemical water splitting to produce hydrogen is strongly desired for renewable energy *** this article,a novel bifunctional catalytic electrode of insitu-grown type for alkaline water splitting based on FeCoNi alloy substrate has been successfully prepared via a facile one-step hydrothermal oxidation route in an alkaline hydrogen peroxide *** shows that the matrix alloy with the atom ratio 4∶3∶3 of Fe∶Co∶Ni can obtain the best catalytic performance when hydrothermally treated at 180℃for 18 h in the solution containing 1.8 M hydrogen peroxide and 3.6 M sodium *** as-prepared Fe_(0.4)Co_(0.3)Ni_(0.3)-1.8 electrode exhibits small overpotentials of only 184 and 175 mV at electrolysis current density of 10 mA cm^(-2)for alkaline OeR and HeR processes,*** overall water splitting at electrolysis current density of 10 mA cm^(-2)can be stably delivered at a low cell voltage of 1.62 *** characteristics including the large specific surface area,the high surface nickel content,the abundant catalyst species,the balanced distribution between bivalent and trivalent metal ions,and the strong binding of in-situ naturally growed catalytic layer to matrix are responsible for the prominent catalytic performance of the Fe_(0.4)Co_(0.3)Ni_(0.3)-1.8 electrode,which can act as a possible replacement for expensive noble metal-based materials.

关键词： alkaline water electrolysis bifunctional.electrocatalyst FeCoNi alloy hydrothermal oxidation in-situ growing

Using proteomics to compare the molecular structures of sulfide and permeate-depilated sheepskins

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Collagen and leather 2024年第1期6卷 70-84页

作者： Yi-Hsuan Tu Trevor S.loo Mark l.Patchett Gillian e.Norris School of Natural Sciences Massey UniversityPalmerston NorthNew Zealand

An environmentally friendly method using real or artificial bovine milk permeate to both depilate and preserve sheepskins has been reported which completely and cleanly removed the wool from the hair follicle and had no detrimental.effects on the skin.A proteomic analysis,assessing the relative abundance of proteins in matched permeate-depilated and chemically depilated(sulfide)sheepskins,showed variations in the levels of specific collagen types in the skin's basement membrane and other proteins associated with the *** findings were corroborated by biochemical analyses of matched permeate depilated and raw skin samples,and provide cl.es to the mechanism of non-invasiveand complete *** also support the observation that permeate-depilated skins were smoother than their sulfide-depilated counterparts and resul.ed in leather with a superior surface.

关键词： Collagen Collagen crosslinks Glycosaminoglycan Proteomics Relative abundance