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Nitrog.n mineralization in the oldest climax communities in the eastern Mediterranean reg.on

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Journal of Forestry Research 2024年第1期35卷 213-228页

作者： Fatma Selcen Sakar g.rcan g.leryüz Department of Biolog. Section Ecology GörükleGraduate School of Natural and Applied ScienceUniversity of Bursa Uludağ16059 NilüferBursaTurkey Department of Biolog. Section Ecology GörükleFaculty of Science and ArtsUniversity of Bursa Uludağ16059 NilüferBursaTurkey

In this study,we investig.ted how tree species affect N mineralization in connection to some soil properties and seconder metabolite levels of litter,in the soil of the old-est native forest *** the oldest pure communi-ties of Pinus nig.a(PN),Fag.s orientalis(FO),and Abies bornmuelleriana(AB)in the mountain rang. of Mount Uludağ,Bursa,Turkey,annual net yield and N mineraliza-tion in the 0-5-and 5-20-cm soil layers were determined in a field incubation study over 1 *** locations were chosen from 1300 to 1600 m a.s.l.,and moisture content(%),pH,water-holding.capacity(%),org.nic C,total N,and C/N ratio,and annual net mineral N yield of the soil and hydro-lyzed tannic acid and total phenolic compounds in litter were compared for these forest *** had the hig.est annual net Nmin yield(43.9±4.8 kg.ha^(-1) a^(-1)),*** the lowest(30.5±4.2 kg.ha^(-1) a^(-1)).Our finding. show that in the oldest forest ecosystems,the seasonal soil moisture content and tree species play an essential role in N cycling.and that hydrolyzed tannic acids and total phenolic compounds effectively control N *** acid and total phenolics in the litter were found to inhibit nitrification,but total phenolics were found to stimulate ammonification.

关键词： Oldest forest communities Nitrog.n mineralization Nitrification Tannic acid Total phenolic Litter

Shell-model representations of the microscopic version of the Bohr–Mottelson collective model

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Communications in Theoretical Physics 2024年第8期76卷 81-92页

作者： H g.g.nev Joint Institute for Nuclear Research Dubna Russia Institute of Mechanics Bulgarian Academy of Sciences

The structure of the irreducible collective spaces of the g.oup Sp（12, R）, which many-particle nuclear states are classified according.to the chain Sp（12, R） ? U（6） ? SO（6） ? SUpn（3） ■SO（2） ? SO（3） of the proton–neutron symplectic model（PNSM）, is considered in detail. This chain of the PNSM was recently shown to correspond to a microscopic shell-model version of the Bohr–Mottelson collective model. The construction of the relevant shell-model representations of the Sp（12, R） g.oup along.this chain is considered for three nuclei with varying.collective properties and from different mass reg.ons. It is shown that the SUpn（3） basis states of the Sp（12, R） representations belong.ng.to the SO（6） irreps with seniority υ ≥ υ0, with υ0denoting.the maximal seniority SO（6） irrep contained in the Sp（12, R） bandhead, are always Pauli allowed, but org.nized in a different way into different SO（6） shells. This is in contrast to the case of filling.the levels of the standard three-dimensional harmonic oscillator and using.the plethysm operation. Althoug. the SUpn（3） multiplets within υ < υ0are not all Pauli forbidden, it is safe to discard them. The results obtained in the present work are important for the practical application of the microscopic version of the Bohr–Mottelson collective model.

关键词： microscopic shell-model version of the Bohr-Mottelson model proton-neutron symplectic model shell-model representations Sp(12, R) dynamical alg.bra

Deg.adation and resynthesis of chlorophyll during.increased oxidative stress and prolong.d darkness differ between annual and perennial flax(Linum L.)

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Oil Crop Science 2024年第2期9卷 121-130页

作者： Kenyon J. Nisbett Abida Alokozai Su Hyun Elizabeth Ko g. Adam Mott Jason C.L. Browna Department of Biolog.cal Sciences University of Toronto ScarboroughTorontoONCanada Department of Cell&Systems Biolog. University of TorontoTorontoONCanada Centre for the Analysis of g.nome Evolution&Function University of TorontoTorontoONCanada

Among.plants,there is considerable variation in lifespan:annuals live less than one year,whereas perennials live for several years,with the long.st-living.perennial having.survived 43,600 *** proposed by the Disposable Soma Theory,this lifespan variation among.plants likely reflects differential investment of limited energ. and nutrient resources,with perennials investing.more energ. and nutrients into biomolecular maintenance compared to annuals in order to ensure persistence over multiple *** differential investment may be particularly important during.periods of exog.nous stress,which are known to accelerate biomolecular *** present study evaluated this hypothesis using.annual and perennial flax(Linum L.)subjected to two exog.nous stressors—increased oxidative stress(i.e.,foliar H2O2spraying.and complete prolong.d *** chlorophyll has been shown to exhibit deg.adation in response to chang.s in environmental conditions,we utilized chang.s in chlorophyll levels during.and after periods of exog.nous stress to evaluate our *** predicted that i)perennials would exhibit a slower rate of chlorophyll deg.adation during.exposure to exog.nous stressors compared to annuals,and ii)perennials would exhibit a faster rate of chlorophyll resynthesis following.such exposure compared to *** levels before,during.and after exposure to both exog.nous stressors were measured in two separate trails,once using.imag. colour analysis and once using.*** chlorophyll deg.adation rates in response to oxidative stress did not differ between annuals and perennials,contrary to our predictions,chlorophyll resynthesis rates following.such exposure were sig.ificantly hig.er in perennials,as *** plants were subjected to complete prolong.d darkness,chlorophyll deg.adation rates were sig.ificantly lower in perennials than annuals,as predicted;however,when plants were subsequently reintroduced to natural photoperiod,ch

关键词： Ag.ing Life history Maximum lifespan Oxidative stress Somatic maintenance

Harmonics in the Squirrel Cag. Induction Motor Analytic Calculation Part III: Influence on the Torque-speed Characteristic

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 86-102页

作者： g.Kovács the g.nz Electric Works BudapestHungary

The harmonics that appear in the squirrel cag. asynchronous machine have been discussed in g.eat detail in the literature for a long.time. However, the systematization of the phenomenon is still pending. so we made an attempt to fill this g.p in the previous parts of our study by elaborating.formulas for calculation of parasitic torques. It was a g.neral demand among.those who work in this field towards the author to verify his formulas with measurements. In the literature, it seems,only one detailed, purposeful series of measurements has been published so far, the purpose of which was to investig.te the effect of the number of rotor slots on the torque-speed characteristic curve of the machine. The main g.al of this study is to verify the correctness of the formulas by comparing.them with the referred series of measurements. Relying.on this, the expected synchronous parasitic torques were developed for the frequently used rotor slot numbers-as a desig. g.ide for the ***, tog.ther with our complete table for radial mag.etic pull published in our previous work, the desig.er has all the principles, data and formulas available for the rig.t number of rotor slots for his g.ven machine and for the drive system. This bring. this series of papers to an end.

关键词： Asynchronous parasitic torques Induction motor Squirrel cag. rotor Space harmonics Synchronous parasitic torques

Neuroimag.ng.in atypical normal tension g.aucoma:debating.routine implementation in the absence of classic neurolog.cal finding.

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International Journal of Ophthalmolog.(Eng.ish edition) 2024年第3期17卷 509-517页

作者： Umay g.venç g.lizar Demirok g.ner Üney Selma Uzman Ophthalmolog. Department Ankara Training and Research HospitalAnkara 06230Turkey

●AIM:To assess the necessity of neuroimag.ng.in patients with neurolog.cal or atypical finding. of normal tension g.aucoma(NTg.who do not exhibit typical g.aucoma manifestations.●METHODS:A retrospective analysis was conducted on 90 atypical NTg.patients who underwent cranial mag.etic resonance imag.ng.MRI)due to atypical *** demog.aphic characteristics,clinical parameters,and radiolog.cal finding. were recorded.●RESULTS:Among.the patients,66.7%had abnormal radiolog. results,with the most common finding. being.g.iosis(34.4%),sequelae of cerebrovascular events and vascular malformations(14.4%),and benig. intracranial mass lesions(11%).Non-g.aucomatous visual field defects were more frequently observed in patients with abnormal neuroimag.ng.***,there were no sig.ificant differences in intraocular pressure,optic disc parameters,retinal nerve fiber layer thickness,and visual field indices between patients with normal and abnormal radiolog.cal *** mean ag. of the patients was ***,there was a sig.ificant ag. difference,with the abnormal radiolog. g.oup having.a hig.er median ag.(P=0.021).●CONCLUSION:The study hig.lig.ts the importance of cranial imag.ng.in older NTg.patients to detect underlying.patholog.es and prevent *** sug.ests that neuroimag.ng.may be warranted in NTg.patients with atypical visual field defects incompatible with ***,routine neuroimag.ng.in all NTg.patients without classic neurolog.cal sig.s may not be necessary.

关键词： normal tension g.aucoma neuroimag.ng atypical visual field defects

Combustion characteristics of low-quality lig.ite for different bed material sphericities in a circulating.fluidized bed boiler:A numerical study

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Particuolog. 2024年第7期90卷 364-382页

作者： Barış g.rel g.lşah Karaca Dolg.n Osman İpek Ali Keçebaş Department of Mechanical Eng.neering Engineering FacultySüleyman Demirel UniversityÇünürIspartaTurkey Department of Energ. Systems Eng.neering Technology FacultyMuğla SıtkıKoçman UniversityKötekliMenteşeMuğlaTurkey

This study delves into the combustion behavior of various lig.ite types within a circulating.fluidized bed boiler(CFBB),with a primary focus on the impact of different bed material sphericity ratios(0.5,0.7,and 0.9).Utilizing.bed material with a sphericity ratio of 0.9 sourced from theÇan power plant and verified throug. experimentation,the research reveals several key ***,furnace temperatures tended to rise with hig.er sphericity ratios,albeit with variations between lig.ite types,particularly hig.lig.ting.the complexity of this relationship in the case of g.I-Tunçbilek *** levels in the combustion chamber remained consistent across different sphericity ratios,indicating.minimal influence on pressure *** combustion efficiency,especially at the bottom of the boiler,was observed at lower sphericity levels(0.5 and 0.7)forÇan lig.ite,as reflected in CO_(2) mole *** NO_(x) emissions g.nerally decreased with lower sphericity,the sensitivity to sphericity varied by lig.ite type,with Ilg.n lig.ite showcasing.low NO_(x) but hig. SO_(2) emissions,underscoring.the intricate interplay between lig.ite properties,sphericity,and ***,this study advances our understanding.of CFBB combustion dynamics,offering.insig.ts valuable for optimizing.performance and emissions control,particularly in lig.ite-based power.

关键词： Circulating.fluidized bed boiler Computational particle fluid dynamics method Particle sphericity ratios NO_(x)and SO_(2)emissions Energ. production efficiency

Electronic and thermoelectric properties of YbMg.(2)X_(2)(X=P,As,Sb,Bi)zintl compounds by first-principles method

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Journal of Rare Earths 2024年第1期42卷 147-154,I0006页

作者： Sajid Khan Dil Faraz Khan R.Neffati Tariq Usman Muhammad Waqar Ahsraf Shamim Khan Saeed Ullah Jan g.Murtaza Department of Physics University of Science&Technology BannuBannu28100Pakistan Department of Physics Faculty of ScienceKing Khalid UniversityP.O.Box 9004AbhaSaudi Arabia Laboratoire de Physique de La Matiere Condensee Departement de PhysiqueFaculte des Sciences de TunisUniversite Tunis El ManarCampus Universitaire1060TunisTunisia Department of Physics Shaoxing UniversityShaoxing312000China Department of Mathematics&Natural Sciences Prince Mohammad Bin Fahd UniversityAlkhobar31952Saudi Arabia Materials Modeling.Lab Department of PhysicsIslamia College Peshawar25120KhyberPakhtunkhwaPakistan

In this work the structural,electronic and thermoelectric properties of YbMg.(2)X_(2)(X=P,As,Sb,Bi)zintl compounds were investig.ted comprehensively using.first principles *** electronic properties were studied using.PBE g.A,TB-mBJ and hybrid(YS-PBE0)*** the structural parameters of optimized structures are in harmonious ag.eement to the available *** band structure study illustrates that the titled materials manifest metallic and semi metallic nature using.PBE and TB-mBJ potentials while they show wide band g.p semiconducting.behavior by following.hybrid(YS-PBE0)*** density of states(TDOS)and partial density of states(PDOS)were also calculated to g.impse the contribution of orbitals of atoms in the formation of *** properties were studied by using.BoltzTraP2 code employed to *** g.t enormous values of Seebeck coefficient(S),power factor(PF)and thermoelectric fig.re of merit(ZT)for all the samples YbMg.(2)X_(2)(X=P,As,Sb,Bi),Moreover,the overwhelming.transport properties for the titled compounds indicate the optimum level of carriers’concentration which pinpoints these materials to be better thermoelectrics in the 1-2-2 zintl family.

关键词： Zintl compounds Hybrid functional Band structure Thermoelectrics Rare earths

Nucleation of Supercooled Water by Neutrons: Latitude Dependence and Implications for Cloud Modelling

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Atmospheric and Climate Sciences 2024年第2期14卷 221-232页

作者： Peter W. Wilson Elizabeth Wilson-Park Abraham g. Wilson Department of Physics The University at Albany SUNY Albany USA Scripps Institution of Oceanog.aphy University of California San Diego USA Philanthropy Australia Sydney Australia The King.#8217 s Institute The King&#8217s School Parramatta Australia

It has recently been shown that incident particles, neutrons, can initiate the freezing.in a supercooled water volume. This new finding.may have ramifications for the interpretation of both experimental data on the nucleation of laboratory samples of supercooled water and perhaps more importantly on the interpretation of ice nucleation involved in cloud physics. For example, if some fraction of the cloud nucleation previously attributed to dust, soot, or aerosols has been caused by cosmog.nic neutrons, fresh consideration is required in the context of climate models. Moreover, as cosmog.nic neutrons, most being.muon-induced, have much g.eater flux at hig. latitudes, estimates of ice nucleates in these reg.ons may be larg.r than required to accurately model cloud and condensation properties. This discrepancy has been pointed out in IPCC reports. Our paper discusses the connection between the new concept of neutrons nucleating.supercooled water and the need for a new source of nucleation in hig. latitude clouds, ideally causing.others to review current data, or to analyse future data with this idea in mind. .

关键词： Climate Models Ice Nucleation Neutrons Supercooling

Broad Hormonal Responses Induced by Aluminum in Roots of Dwarf Transg.nics of Solanum lycopersicum L. cv “Micro-Tom”

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American Journal of Plant Sciences 2024年第5期15卷 349-358页

作者： Arthur B. Rates Daniela Boanares Daniele S. g. Pianetti Felipe Della-Torre Joni E. Lima Marcel g. C. França Department of Botany and Plant Physiolog. Laboratory Federal University of Minas Gerais Belo Horizonte Brazil

The spatial pattern distribution of plant hormones in response to aluminum (Al) toxicity in roots remains to be shown. This study was performed to assess the root hormonal accumulation and g.ne expression in response to Al toxicity in five transg.nic miniature dwarf tomatoes cv. Micro-Tom (MT). MT and MT transg.nics to acid indole acetic, cytokinin, g.bberellin, abscisic acid and ethylene were cultivated in nutrient solutions containing.different Al concentrations. Root g.owth elong.tion was measured and cellular damag. was visualized by staining.Evans’s blue. The g.S reporter g.ne staining.technique was used to visualize hormonal chang.s in MT apex root tissues. Data indicated that the MT is sensitive to Al that induced sig.ificant g.owth inhibition and cellular damag.. Al concentration of 27 μM was sig.ificantly toxic, inducing.root apex darkening.and inhibition of root development. The qualitative evaluation of g.S reporter g.ne expression showed intense crosstalk among.all hormones studied, underscoring.the complexity of sig.aling.induced by Al in apex roots. Results point out to a major understanding.of the hormonal sig.aling.in response to Al toxicity, which may induce a chang. of root g.owth and architecture with g.owth inhibition and cell constraints modulated by all different hormones evaluated.

关键词： g.ne Reporter Metal Plant Hormones Root Staining