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Finite groups whose n-maximal subgroups are σ-subnormal

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Science China Mathematics 2019年第7期62卷 1355-1372页

作者： Wenbin Guo Alexander n. Skiba School of Mathematical Sciences University of Science and Technology of China Hefei 230026 China Department of Mathematics and Technologies of Programming Francisk Skorina Gomel State University Gomel 246019 Belarus

Let σ={σi | i ∈ I} be some partition of the set of all primes P. A set H of subgroups of G is said to be a complete Hall σ-set of G if every member ≠ 1 of H is a Hall σi-subgroup of G, for some i ∈ I, and H contains exactly one Hall σi-subgroup of G for every σi ∈σ(G). A subgroup H of G is said to be:σ-permutable or σ-quasinormal in G if G possesses a complete Hall σ-set H such that HAx= AxH for all A ∈ H and x ∈ G:σ-subnormal in G if there is a subgroup chain A = A0≤A1≤···≤ At = G such that either Ai-1■Ai or Ai/(Ai-1)Ai is a finite σi-group for some σi ∈σ for all i = 1,..., *** Mn n-1 n, then Mn is said to be an n-maximal subgroup of G. If each n-maximal subgroup of G is σ-subnormal(σ-quasinormal,respectively) in G but, in the case n > 1, some(n-1)-maximal subgroup is not σ-subnormal(not σ-quasinormal,respectively) in G, we write mσ(G)= n(mσq(G)= n, respectively).In this paper, we show that the parameters mσ(G) and mσq(G) make possible to bound the σ-nilpotent length lσ(G)(see below the definitions of the terms employed), the rank r(G) and the number |π(G)| of all distinct primes dividing the order |G| of a finite soluble group G. We also give the conditions under which a finite group is σ-soluble or σ-nilpotent, and describe the structure of a finite soluble group G in the case when mσ(G)=|π(G)|. Some known results are generalized.

关键词： finite group n-maximal subgroup σ-subnormal subgroup σ-quasinormal subgroup σ-soluble group σ-nilpotent group

Probit Analysis of Carbamate-Pesticide-Toxicity at Soil-Water Interface to n_2-Fixing Cyanobacterium Cylindrospermum sp.

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Rice science 2015年第2期22卷 89-98页

作者： Rabindra n.PADHY Shakti RATH Department of Botany BJB Autonomous College

Toxicity-data of two carbamate insecticides, carbaryl and carbofuran, and three fungicides, ziram, zineb and mancozeb with rice-field n2-fixing cyanobacterium Cylindrospermum sp., obtained by in vitro growth and at soil-water interface, were analyzed by the probit method. Growth enhancing concentration, no-observed effective concentration, minimum inhibitory concentration, the highest permissive concentration and lethal concentration100 （LCloo） were determined experimentally. The LC^o values of carbaryl, carbofuran, ziram, zineb and mancozeb in n2-fixing liquid medium were 56.2, 588.8, 0.07, 4.2 and 3.4 IJg/mL, respectively, whereas the corresponding LCloo values were 100.0, 1500.0, 0.17, 25.0 and 9.0 IJg/mL, respectively. The LC50 values of these pesticides in succession in n2-fixing agar medium were 44.7, 239.9, 0.07, 1.8 and 2.3 IJg/mL, respectively, whereas the corresponding LC100 values were 100.0, 600.0, 0.17, 10.0 and 7.0 IJg/mL, respectively. Similar results with nitrate supplemented liquid and agar media indicated that nitrate supplementation had toxicity reducing effect. The LCso and LC^oo values of toxicity in the n2-fixing liquid medium at soil-water interface were 91.2 and 200.0 IJg/mL for carbaryl, 2 317 and 6 000 pg/mL for carbofuran, 0.15 and 0.50 pg/mL for ziram, 16.4 and 50.0 pg/mL for zineb, and 7.2 and 25.0 pg/mL for mancozeb, respectively. Each LC^oo value at soil- water interface with a pesticide was significantly higher than its corresponding LCloo value at liquid/agar media. It can be concluded that, under the n2-fixing conditions, the cyanobacterium tolerated higher levels of each pesticide at soil-water interface.

关键词： carbamate pesticide Cylindrospermum sp. cyanobacterium lethal concentration probitanalysis soil-water interface

Re-folded structure of syn-orogenic granitoids(Padrón dome, nW Iberia):Assessing rheological evolution of cooling continental crust in a collisional setting

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Geoscience Frontiers 2019年第2期10卷 651-669页

作者： Rubén Díez Fernández Francisco J.Rubio Pascual Luis Miguel Martín Parra Departamento de Geodinámica Estratigrafía y PaleontologíaFacultad de Ciencias GeológicasUniversidad Complutense de Madrid Instituto Geológico y Minero de Espana

This contribution discusses about the rheological, kinematic and dynamic frameworks necessary to produce recumbent and upright folds from syn-orogenic granitic massifs that were formed during an early stage of magma genesis related to the onset of a migmatitic dome. Syn-kinematic granitoids occurring within the high-grade infrastructure of the Padron migmatitic dome(nW Iberia) are deformed into largescale recumbent folds(D_2) that are later affected by upright folds(D_3). Petrostructural analysis of a selected area of this dome reveals that after a period of crustal thickening(D_1), nnW-directed extensional flow gave way to recumbent folds and penetrative axial plane foliation(S_2). Superimposed subhorizontal compression resulted in upright folds(D_3). A closer view into the dynamics of the dome allows exploring the factors that may condition the nucleation of folds with contrasting geometries during progressive deformation of molten continental crust. The formation of folds affecting syn-kinematic granitoids suggests a cooling metamorphic path in migmatitic domes. Active and passive folding mechanisms require a crystallizing(cooling) magma to nucleate folds. A more competent metamorphic host inhibits fold nucleation from much less competent magmas. As it crystallizes, magma becomes more rigid(competent),and approaches viscosity values of its host. Passive folding is favored when no significant competence contrast exists between magma and host, so this folding mechanism is more likely shortly after magma genesis and emplacement. In such conditions, and under dominant subhorizontal flow accompanied by flattening(D_2),passive folding would produce isoclinal recumbent geometries. Further magma cooling introduces a shift into the rheological behavior of partially molten crust. Thereon, crystallizing magma bodies would represent significant competence contrasts relative to their host. At this point, buckling is a more likely folding mechanism, and more regular, buckle fo

关键词： Recumbent folds Migmatitic domes Partial melting Crustal-derived granitoids Orogenic collapse Variscan orogen

Better together? Treating traumatic brain injury with minocycline plus n-acetylcysteine

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neural Regeneration Research 2022年第12期17卷 2589-2592页

作者： Siobhán Lawless Peter J.Bergold Graduate Program in neural and Behavioral Sciences State University of New York-Downstate Health Sciences UniversityBrooklynNYUSA Department of Physiology and Pharmacology State University of New York-Downstate Health Sciences UniversityBrooklynNYUSA

Traumatic brain injury has a complex pathophysiology that produces both rapid and delayed brain damage. Rapid damage initiates immediately after injury. Treatment of traumatic brain injury is typically delayed many hours, thus only delayed damage can be targeted with drugs. Delayed traumatic brain injury includes neuroinflammation, oxidative damage, apoptosis, and glutamate toxicity. Both the speed and complexity of traumatic brain injury pathophysiology present large obstacles to drug development. Repurposing of Food and Drug Administration-approved drugs may be a highly efficient approach to get therapeutics to the clinic. This review examines the preclinical outcomes of minocycline and n-acetylcysteine as individual drugs and compares them to the minocycline plus n-acetylcysteine combination. Both minocycline and n-acetylcysteine are Food and Drug Administration-approved drugs with pleiotropic therapeutic effects. As individual drugs, minocycline and n-acetylcysteine are well tolerated, with known pharmacokinetics, and enter the brain through an intact blood-brain barrier. At concentrations greater than needed for antimicrobial action, minocycline is a potent anti-inflammatory minocycline, also acts as an antioxidant and inhibits multiple enzymes that promote brain injury including metalloproteases, caspases, and polyADP-ribose-polymerase-1. n-acetylcysteine alone is also an antioxidant. It increases brain glutathione, prevents lipid oxidation, and protects mitochondria. n-acetylcysteine also acts as an anti-inflammatory as well as increases extracellular glutamate by activating the X;cystine-glutamate antitransporter. These multiple actions of minocycline and n-acetylcysteine have made them attractive candidates to treat traumatic brain injury. When first dosed within the one hour after injury, either minocycline or n-acetylcysteine improves a diverse set of therapeutic outcome measures in multiple traumatic brain injury animal models. A small number of clinical

关键词： clinical trial outcome measures preclinical testing rodent models of traumatic brain injury therapeutic time window

F4-TCnQ concentration dependence of the current voltage characteristics in the Au/P3HT:PCBM:F4-TCnQ/n-Si(MPS) Schottky barrier diode

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Chinese Physics B 2014年第11期23卷 512-522页

作者： E.Yaglioglu O.Tzn Ozmen Department of Physics Faculty of Arts and Sciences Dzce University

In this study, we investigate some main electrical parameters of the gold/poly（3-hexylthiophene）：[6,6]-phenyl C61 bu- tyric acid methyl ester：2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane/n-type silicon （Au/P3HT：PCBM：F4-TCnQ/n- Si） metal-polymer-semiconductor （MPS） Schottky barrier diode （SBD） in terms of the effects of F4-TCnQ concentration （0%, 1%, and 2%）. F4-TCnQ-doped P3HT：PCBM is fabricated to figure out the p-type doping effect on the device per- formance. The main electrical parameters, such as ideality factor （n）, barrier height （ФB0）, series resistance （Rs）, shunt resistance （Rsh）, and density of interface states （nss） are determined from the forward and reverse bias current-voltage （l-V） characteristics in the dark and at room temperature. The values of n, Rs, ФB0, and nss are significantly reduced by using the 1% F4-TCnQ doping in P3HT：PCBM：F4-TCnQ organic blend layer, additionally, the carrier mobility and current are increased by the soft （1%） doping. The most ideal values of electrical parameters are obtained for 1% F4-TCnQ used diode. On the other hand, the carrier mobility and current for the hard doping （2%） become far away from the ideal diode values due to the unbalanced generation of holes/electrons and doping-induced disproportion when compared with 1% F4-TCnQ doping. These results show that the electrical properties of MPS SBDs strongly depend on the F4-TCnQ doping and doping concentration of interfacial P3HT：PCBM：F4-TCnQ organic layer. Moreover, the soft F4-TCnQ dop- ing concentration （1%） in P3HT：PCBM：F4-TCnQ organic layer significantly improves the electrical characteristics of the Au/P3HT：PCBM：F4-TCnQ/n-Si （MPS） SBDs which enables the fabricating of high-quality electronic and optoelectronic devices.

关键词： P3HT:PCBM:F4-TCnQ interfacial organic layer F4-TCnQ doping concentration Schottky bar-rier diodes I-V characteristics

Mind the gap among patches in arid plant communities:rapid root proliferation in response to n addition

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Journal of Plant Ecology 2019年第1期12卷 89-95页

作者： Maria Fernanda Reyes Martín RAguiar Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura(IFEVA)and Consejo nacional de Investigaciones Científicas y Técnicas(COnICET) Universidad de Buenos AiresAv.San Martín 4453Buenos Aires C1417DSEArgentina

Aims In arid communities,it has been proposed that individual plants can extend their roots beyond their canopy exploring neighbour-ing bare ground *** becomes relevant in systems where the vegetation is distributed in patches surrounded by bare ***,whether roots of different species may be overlapping under bare ground areas is still *** factors control-ling root responses when no plants appear to be directly influ-encing the gap among patches are still *** aim of our study was to detect perennial grasses responses to an n enrich-ment *** In a semi-arid steppe(Patagonia,Argentina),we buried root traps filled with sieved soil with and without n addition,under bare soil *** were harvested after 4 and 6 *** neighbour-hoods(30 cm in diameter)included at least three of the dominant tussock *** harvests,we identified species in the traps by root traits and quantified diversity,biomass and specific relative growth *** Findings Bare ground areas show simultaneous root growth of different *** of perennial grass roots was higher with n addition than without it in the first harvest(4 months),but this difference disappeared in the second harvest(6 months).Root biomass was maximal after 6 months in n addition *** preferred by herbivores(Bromus pictus and Poa ligularis)showed rapid growth and responses to n *** between harvests may be an indicative that n pulses interact with rising temperatures and soil water content as growing season progress.

关键词： belowground community ecology grass species roots Patagonian steppe patchiness root growth rates zone of influence

Effect of reinforcement content on the adhesive wear behavior of Cu10Sn5ni/Si3n4 composites produced by stir casting

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International Journal of Minerals,Metallurgy and Materials 2017年第9期24卷 1052-1060页

作者： K.Sanesh S.Shiam Sunder n.Radhika Department of Mechanical Engineering Amrita School of EngineeringCoimbatore 64112Amrita Vishwa VidyapeethamAmrita UniversityIndia

The main objective of this paper was to fabricate CuSnni alloy and its composites reinforced with various contents of Sinparticles(5wt%, 10wt%, and 15wt%) and to investigate their dry sliding wear behavior using a pin-on-disk tribometer. Microstructural examinations of the specimens revealed a uniform dispersion of Sinparticles in the copper matrix. Wear experiments were performed for all combinations of parameters, such as load(10, 20, and 30 n), sliding distance(500, 1000, and 1500 m), and sliding velocity(1, 2, and 3 m/s), for the alloy and the composites. The results revealed that wear rate increased with increasing load and increasing sliding distance, whereas the wear rate decreased and then increased with increasing sliding velocity. The primary wear mechanism encountered at low loads was mild adhesive wear, whereas that at high loads was severe delamination wear. An oxide layer was formed at low velocities, whereas a combination of shear and plastic deformation occurred at high velocities. The mechanism at short sliding distances was ploughing action of Sinparticles, which act as protrusions; by contrast, at long sliding distances, direct metal–metal contact occurred. Among the investigated samples, the Cu/10wt% Sincomposite exhibited the best wear resistance at a load of 10 n, a velocity of 2 m/s, and a sliding distance of 500 m.

关键词： copper matrix composites stir casting adhesive wear wear mechanisms

MECHAnICAL PROPERTIES AnD MICROSTRUCTURES OF Ti(C,n) BASED CERMETS

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中国有色金属学会会刊：英文版 1996年第4期6卷 117-121页

作者： Liu, n Hu, ZH Cui, K Liu, CL AnHUI InST TECHnOL DEPT MAT SCI & ENGNHEFEI 230069PEOPLES R CHINA HUAZHOnG UnIV SCI & TECHnOL WUHAN 430074PEOPLES R CHINA BEIJInG GEn RES InST IROn & STEEL BEIJING 100081PEOPLES R CHINA

ＭＥＣＨＡＮＩＣＡＬＰＲＯＰＥＲＴＩＥＳＡＮＤＭＩＣＲＯＳＴＲＵＣＴＵＲＥＳＯＦＴｉ（Ｃ，Ｎ）ＢＡＳＥＤＣＥＲＭＥＴＳ￥ＬｉｕＮｉｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅｒｉ... 详细信息

ＭＥＣＨＡＮＩＣＡＬＰＲＯＰＥＲＴＩＥＳＡＮＤＭＩＣＲＯＳＴＲＵＣＴＵＲＥＳＯＦＴｉ（Ｃ，Ｎ）ＢＡＳＥＤＣＥＲＭＥＴＳ￥ＬｉｕＮｉｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅｒｉｎｇ，ＡｎｈｕｉＩｎｓｔｉｌｕｔｅ...

关键词： Ti(C,n) based cermets mechanical properties microstructure

Jacobi polynomials and non-singlet structure function F_2 (x,Q^2) up to n^3LO

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Chinese Physics C 2010年第9期34卷 1479-1481页

作者： Ali n.Khorramian S.Atashbar Tehrani Physics Department Semnan University School of Particles and Accelerators Institute for Research in Fundamental Sciences (IPM)

In this paper we present the non-singlet QCD analysis to determine valence quark distribution up to four *** obtain the fractional difference between the 4-loop and the 1-,2and 3-loop presentations of xu v （x,Q^2） a... 详细信息

关键词： PDFs DIS data QCD fit