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leaf habit differentiation explains trait tradeoffs across savanna woody plants

Forest Ecosystems 2024年第3期11卷 287-295页

作者： Yangsiding Wang Da Yang german Vargas g. guangyou Hao Jennifer s.Powers Yan Ke Qin Wang Yunbing Zhang Jiaolin Zhang CAs Key laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China University of Chinese Academy of sciences Beijing 100049China school of Biological sciences University of UtahSalt Lake CityUT 84112USA CAs Key laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Department of Ecology Evolution and BehaviorUniversity of MinnesotaSt PaulMN 55108USA

Identifying how leaf habit subdivisions link to the fast–slow and avoidance–tolerance trait tradeoffs can provide new insight into divergence in ecophysiological strategies among plant functional groups. Here, we tested a hypothesis that the differentiation across deciduous, semi-deciduous and evergreen woody species contributes to physiological trait tradeoffs in a dry-hot valley savanna. We investigated 11 photosynthetic, morphological and hydraulic traits of 24 species including 8 deciduous, 10 semi-deciduous and 6 evergreen species. Deciduous species were grouped in the fast and avoidance side associated with high values of maximum photosynthetic rates,stomatal conductance and leaf size, while evergreen species were grouped in the slow and tolerance side associated with high photosynthetic water use efficiency, leaf mass per area, sapwood density, Huber value, leaf water potential at turgor loss point and water potential causing 50% loss of stem hydraulic conductance. semideciduous species generally had intermediate trait values and represented different physiological characteristics when compared to deciduous and evergreen species. The physiological trait tradeoffs showed a close linkage to the differentiation of these three leaf habits. Our findings clearly reveal trait tradeoffs related to fast–slow and avoidance–tolerance strategies among diverse savanna plants, suggesting a syndrome in multiple ecophysiology strategies across different leaf habits.

关键词： Dry-hot habitat gas exchange Hydraulics Phenology Tolerance Valley savanna

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Effect of solidification cooling rate on microstructure and tribology characteristics of Zn-4si alloy

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 362-373页

作者： F.Akbari M.golkaram s.Beyrami g.shirazi K.Mantashloo R.Taghiabadi M.saghafi Yazdi I.Ansarian Department of Metallurgy and Material science Imam Khomeini International University(IKIU)Qazvin ***Iran

The main objective of this work was to modify the microstructure and enhance the tribological properties of a new Zn-4si al-loy through a high solidification cooling rate(sCR).According to the results,by increasing the sCR from 2.0 to 59.5℃/s the average size of primary si particles and that of the grains reduced from 76.1 and 3780μm to less than about 14.6 and 460μm,***-ing the sCR also enhanced the microstructural homogeneity,decreased the porosity content(by 50%),and increased the matrix hardness(by 36%).These microstructural changes enhanced the tribological *** instance,under the applied pressure of 0.5 MPa,an in-crease in the sCR from 2.0 to 59.5℃/s decreased the wear rate and the average friction coefficient of the alloy by 57%and 23%,*** wear mechanism was also changed from the severe delamination,adhesion,and abrasion in the slowly-cooled alloy to the mild tribolayer delamination/abrasion in the high-cooling-rate-solidified sample.

关键词： zinc-silicon alloy primary silicon solidification cooling rate tribology sliding wear

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Highly divergent sympatric lineages of leptotila verreauxi(Aves:Columbidae)suggest a secondary contact area in the Isthmus of Tehuantepec,Mexico

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Avian Research 2024年第1期15卷 12-21页

作者： Orlando J.Espinosa-Chávez Adolfo g.Navarro-sigüenza Hernando Rodríguez-Correa luis A.sánchez-gonzález Museo de Zoología“Alfonso l.Herrera” Depto.de Biología EvolutivaFacultad de CienciasUniversidad Nacional Autonoma de MexicoApdo.Postal 70-399CP 04510Ciudad de MexicoMexico Posgrado en Ciencias Biologicas Unidad de PosgradoEdificio D1◦PisoCircuito de PosgradosCiudad UniversitariaUniversidad Nacional Autonoma de MexicoCoyoacanCP 04510CDMXMexico Escuela Nacional de Estudios superiores Unidad Morelia Universidad Nacional Autonoma de Mexico.Antigua Carretera a Patzcuaro No.8701 Col.Ex Hacienda de San Jose de la HuertaC.P.58190MoreliaMichoacanMexico

Due to a complex geological and biotic history,the Isthmus of Tehuantepec(IT),has been long recognized as a driver for the evolutionary divergence of numerous lowland and highland *** distributed in the lowlands of the American continent,the White-Tipped Dove(leptotila verreauxi)is a polytypic species with 13 recognized *** of these have been recorded in Mexico,and the distribution of three abuts at the IT,suggesting a contact *** estimate phylogenetic patterns,divergence times and genetic differentiation,we examined two mt DNA(ND2 and COI)and one n DNA(β-fibint 7)*** also used correlative ecological niche models(ENM)to assess whether ecological differences across the IT may have acted as a biogeographical *** estimated paleodistributions during the Middle Holocene,last glacial Maximum and last Interglacial,to evaluate the influence of climate changes on the distribution and demographic *** results showed genetically distinct lineages that diverged approximately 2.5 million years *** and ecological factors may have played a dual role in promoting differentiation,but also in the formation of a secondary contact zone in the southern *** ecological niche comparisons indicated that the ecological niche of sympatric lineages at the IT are not identical,suggesting niches divergence;in addition,environmental niche models across the region indicated no abrupt biogeographic barriers,but the presence of regions with low *** results suggest that genetic differentiation originated by a vicariant event probably related to environmental factors,favored the evolution of different ecological ***,the absence of a biogeographic barrier but the presence of less suitable areas in the contact regions,suggest that secondary contact zones may be also maintained by climatic factors for the eastern group,but also by biotic interactions for the western group.

关键词： Biogeographical boundary Humid and dry forests Isthmus of Tehuantepec Phylogeography secondary contact

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Organic-inorganic hybrid materials and architectures in optoelectronic devices: Recent advancements

ChemPhysMater

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ChemPhysMater 2024年第3期3卷 252-272页

作者： M.Arya s.Heera P.Meenu K.g.Deepa Department of Physics University of KeralaThiruvananthapuram 695581India Department of Nanoscience and Nanotechnology University of KeralaThiruvananthapuram 695581India

Organic-inorganic hybrids are next-generation materials for use in high-performance optoelectronic devices owing to their adaptabilities in terms of design and *** article reviews the application of hybrid materials and layers in several widely used optoelectronic devices,i.e.,light amplification by stimulated emission of radiation(lAsER),solar cells,and light-emitting diodes(lEDs).The effects of the incorporation of inorganic particles on photostability and optical gain are analyzed in the first section with reference to dye and perovskite ***,the strategies used in blending inorganic nanostructures into organic solar cells and bulk heterojunctions are *** use of various organic layers as electron-and hole-transport materials in si heterojunction solar cells is reviewed in ***,the benefits of the presence of organic components in quantum-dot-and perovskite-based lEDs are derived from the *** integration of organic and inorganic components with optimal interfaces and morphologies is a challenge in developing hybrid materials with improved efficiencies.

关键词： Optoelectronics Hybrid material Device performance Photostability Advantages

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Utilization of RNA sequencing to investigate olfactory dysfunction in chronic rhinosinusitis without nasal polyps:A pilot study

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World Journal of Otorhinolaryngology-Head and Neck surgery 2024年第1期10卷 29-36页

作者： Jorge A.gutierrez III Jeremy l.Barth Rodney J.schlosser Thomas s.Edwards Timothy l.smith Zachary M.soler Department of Otolaryngology-Head and Neck surgery Medical University of South CarolinaCharlestonSouth CarolinaUSA Department of Regenerative Medicine&Cell Biology Medical University of South CarolinaCharlestonSouth CarolinaUSA Department of Otolaryngology-Head and Neck surgery Oregon Health&Science UniversityPortlandOregonUSA

Objectives:Prior research on olfactory dysfunction in chronic rhinosinusitis(CRs)has focused on patients with polyps and suggests that direct inflammation of the olfactory cleft mucosa plays a contributory *** purpose of this study was to evaluate gene expression in superior turbinate mucosal specimens,comparing normosmic and dysosmic CRs patients without polyps(CRssNP).Methods:Tissue samples were obtained from the superior turbinates of patients with CRssNP at the time of endoscopic sinus *** subsequently underwent RNA sequencing and functional analysis to investigate biological pathways associated with differentially expressed genes between dysosmic(n=7)and normosmic(n=4)***:Differential gene expression analysis comparing dysosmic and normosmic CRssNP patients showed upregulation of 563 genes and downregulation of 327 *** stringent criteria for multiple comparisons,one upregulated gene(Immediate Early Response 3[IER3])had an false discovery rate(FDR)correction adjustedP value considered statistically significant(Pld change 2.69).Reactome functional analysis revealed eight biological pathways significantly different between dysosmic and normosmic patients(Pluding Il-4 and Il-13 signaling,Il-10 signaling,and rhodopsin-like ***:RNA sequencing of the superior turbinates in patients with CRssNP can provide valuable information regarding biological pathways and genes involved in olfactory *** study supports literature suggesting that Type 2 inflammation may play a role in olfactory dysfunction in at least some patients with *** study also prompts questions regarding the role of Il-10,rhodopsin-like receptors,andIER3 in the pathogenesis of olfactory dysfunction.

关键词： chronic rhinosinusitis without nasal polyps olfactory dysfunction RNA sequencing

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Influence of Formulation and Hot-Pressing Conditions on the Performance of Bio-Based Molasses Adhesive for Plywood

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Journal of Renewable Materials 2024年第8期12卷 1383-1397页

作者： sutiawan J. syahfitri A. Kusumah s.s. Hermawan D. sari R.K. Hakim l. Mardawati E. lubis M.A.R. Research Center for Biomass and Bioproducts National Research and Innovation Agency Cibinong 16911 Indonesia Forest Product Department Faculty of Forestry and Environment IPB University Bogor 16680 Indonesia Department of Forest Products Faculty of Forestry Universitas Sumatera Utara Medan 20155 Indonesia Research Collaboration Center for Biomass and Biorefinery BRIN and Universitas Padjadjaran Bandung 40600 Indonesia Department of Agro-Industrial Technology Universitas Padjadjaran Bandung 40600 Indonesia

Molasses can serve as a natural adhesive for plywood and particleboard. However, several disadvantages remain, including lower dimensional stability and low bonding strength compared to other adhesives. Therefore, modifications are needed to use molasses as an adhesive for plywood. This research aims to improve bio-based molasses (MO) adhesive for plywood using citric acid (CA) adhesive. In addition, this research aims to analyze the effect of adding citric acid and to investigate the optimum hot-pressing temperature to produce the best quality plywood. In the first stage, the molasses and citric acid were combined in a ratio of 100:0, 75:25, 50:50, 25:75, 0:100 w/w%. Then, the second stage focuses on analyzing the influences of pressing temperature based on an optimum first stage. The research demonstrated that the addition of CA altered the gelation time, solid content, visc-osity, and pH of the molasses adhesives. In addition, the thermal properties of molasses adhesives were changed after mixing with citric acid. These phenomena indicate changes in characteristics, such as the curing of adhesive. Overall, the characteristics of plywood showed a steady improvement as the CA ratio increased but revealed a significant decline for the 25:75 MO-CA ratio. By raising the pressing temperature from 180°C to 200°C, the quality of plywood was effectively improved. The plywood that was bonded using adhesives with a 50:50 MO-CA ratio exhibited superior mechanical properties and improved dimensional stability compared to the plywood bonded solely with MO. Furthermore, the optimal mechanical and physical properties resulted in plywood bonded with a 50:50 MO-CA ratio when subjected to a pressing temperature of 200°C. The Thermal and FTIR measurements revealed that CA established ester bonds with both the MO and wood veneers. In conclusion, the mechanical characteristics of plywood were improved, while maintaining its excellent dimensional stability. © 2024 The Authors.

关键词： Citric acid composite molasses plywood pressing temperature

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Exploring one material for dual applications:A red-emitting Mg2geO4:Eu3+ nanophosphor for future generation energy efficient WlEDs and dosimetric applications

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Journal of Rare Earths 2024年第10期42卷 1835-1845页

作者： Akshay Arjun g.P.Darshan s.C.sharma H.Nagabhushana D.V.sunitha H.B.Premkumar Department of Physics Faculty of Mathematical and Physical SciencesM.S.Ramaiah University of Applied Sciences Jain University C.N.R.Rao Centre for Advanced Materials Tumkur University school of Applied sciences (Physics) REVA University

The envisaged design and developme nt of individual mate rials to excavate a broader spectrum of desired properties and offer multiple applications are highly *** this in mind,a series of forsterite-structured Mg2geO4:Eu3+（1 mol%-9 mol%） nanophosphors was synthesized via a solution combustion method using oxalyl dihydrazide as a *** X-ray diffraction patterns confirm the orthorhombic crystal system with a Puma space *** results clearly show irregularly shaped cluster-like structures with aggregation of the *** diffuse reflectance spectra,the optical energy band gap of the Mg2geO4:Eu3+（1 mol%-9 mol%） nanophosphors was estimated and obtained to be～4.12-4.32 *** photoluminescence emission spectra exhibit intense peaks at ～579,589,610,661,and 707 nm,which are due to characteristic5D0→7F0,5D0→7F1,5Do→7F2,5D0→7F3and5D0→7F4transitions of Eu3+ions,*** Commission International de l'Eclairage color coordinates are gradually tuned from pale red（0.5980,0.4012） to a pure red（0.6385,0.3611） *** glow peaks showcase excellent super-linear response at low doses of γ-irradiations,indicating that the prepared phosphor can be used in thermoluminescent personal dosimetry which is a biological tissue *** aforementioned results demonstrate that the prepared Mg2geO4:Eu3+（1 mol%-9 mol%） nanophosphors are considered an excellent candidate for dual applications,i.e.,red component in future generation white-light-emitting diodes（WlEDs） and personal dosimetric applications.

关键词： Nanophosphors Photoluminescence Thermoluminescence Dosimetry Photometric properties

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Degradation and resynthesis of chlorophyll during increased oxidative stress and prolonged 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 Biological sciences University of Toronto ScarboroughTorontoONCanada Department of Cell&systems Biology University of TorontoTorontoONCanada Centre for the Analysis of genome 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 longest-living perennial having survived 43,600 *** proposed by the Disposable soma Theory,this lifespan variation among plants likely reflects differential investment of limited energy and nutrient resources,with perennials investing more energy and nutrients into biomolecular maintenance compared to annuals in order to ensure persistence over multiple *** differential investment may be particularly important during periods of exogenous stress,which are known to accelerate biomolecular *** present study evaluated this hypothesis using annual and perennial flax(linum l.)subjected to two exogenous stressors—increased oxidative stress(i.e.,foliar H2O2spraying)and complete prolonged *** chlorophyll has been shown to exhibit degradation in response to changes in environmental conditions,we utilized changes in chlorophyll levels during and after periods of exogenous stress to evaluate our *** predicted that i)perennials would exhibit a slower rate of chlorophyll degradation during exposure to exogenous 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 exogenous stressors were measured in two separate trails,once using image colour analysis and once using *** chlorophyll degradation rates in response to oxidative stress did not differ between annuals and perennials,contrary to our predictions,chlorophyll resynthesis rates following such exposure were significantly higher in perennials,as *** plants were subjected to complete prolonged darkness,chlorophyll degradation rates were significantly lower in perennials than annuals,as predicted;however,when plants were subsequently reintroduced to natural photoperiod,ch

关键词： Ageing life history Maximum lifespan Oxidative stress somatic maintenance

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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 79-90页

作者： H g ganev Joint Institute for Nuclear Research DubnaRussia Institute of Mechanics Bulgarian Academy of SciencesSofiaBulgaria

The structure of the irreducible collective spaces of the group sp(12,R),which many-particle nuclear states are classified according to the chain sp(12,R)⊃U(6)⊃sO(6)⊃sU_(pn)(3)⊗sO(2)⊃sO(3)of the proton-neutron symplectic model(PNsM),is considered in *** chain of the PNsM was recently shown to correspond to a microscopic shell-model version of the Bohr-Mottelson collective *** construction of the relevant shell-model representations of the sp(12,R)group along this chain is considered for three nuclei with varying collective properties and from different mass *** is shown that the sU_(pn)(3)basis states of the sp(12,R)representations belonging to the sO(6)irreps with seniorityυ≥υ0,withυ0 denoting the maximal seniority sO(6)irrep contained in the sp(12,R)bandhead,are always Pauli allowed,but organized in a different way into different sO(6)*** is in contrast to the case of filling the levels of the standard three-dimensional harmonic oscillator and using the plethysm *** the sU_(pn)(3)multiplets withinυll Pauli forbidden,it is safe to discard *** 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 sp(12,R)dynamical algebra shell-model representations

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Fast jet proper motion discovered in a blazar at z=4.72

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science Bulletin 2020年第7期65卷 525-530,M0003页

作者： Yingkang Zhang Tao An sándor Frey shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China University of Chinese Academy of sciences Beijing 100049China Key laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China Konkoly Observatory Research Centre for Astronomy and Earth SciencesKonkoly Thege Miklósút 15-17H-1121 BudapestHungary

High-resolution observations of high-redshift(z > 4) radio quasars offer a unique insight into jet kinematics at early cosmological epochs, as well as constraints on cosmological model *** to the general weakness of extremely distant objects and the apparently slow structural changes caused by cosmological time dilation, only a couple of high-redshift quasars(HRQs) have been studied with parsec-scale resolutions, and with limited number of observing epochs. Here we report on very long baseline interferometry(VlBI) observations of a high-redshift blazar J1430 + 4204(z=4.72) in the 8 gHz frequency band at five different epochs spanning 22 years. The source shows a compact core–jet structure with two jet components being identified within 3 milli-arcsecond(mas) scale. The long time span and multiple-epoch data allow for the kinematic studies of the jet components. That results in a jet proper motion of μ(J1) = 0.017 ± 0.002 mas a^-1 and μ(J2) = 0.156 ± 0.015 mas a^-1, respectively. For the fastest-moving outer jet component J2, the corresponding apparent transverse speed is (19.5 ± 1.9) *** inferred bulk jet lorentz factor C=14.6 ± 3.8 and viewing angle θ=2.2°± 1.6°indicate highly relativistic beaming. The lorentz factor and apparent proper motion are the highest measured to date among the z > 4 jetted radio sources, while the jet kinematics is still consistent with the cosmological interpretation of quasar redshifts.

关键词： Nuclei High-redshift Radio continuum Quasars Individual J1430+4204

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