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Nitrogen mineralization in the oldest climax communities in the eastern Mediterranean region

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

作者： Fatma selcen sakar gürcan güleryüz Department of Biology Section Ecology GörükleGraduate School of Natural and Applied ScienceUniversity of Bursa Uludağ16059 NilüferBursaTurkey Department of Biology Section Ecology GörükleFaculty of Science and ArtsUniversity of Bursa Uludağ16059 NilüferBursaTurkey

In this study,we investigated 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 nigra(PN),Fagus orientalis(FO),and Abies bornmuelleriana(AB)in the mountain range 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(%),organic 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 highest 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 findings 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 Nitrogen mineralization Nitrification Tannic acid Total phenolic Litter

Leaf habit differentiation explains trait tradeoffs across savanna woody plants

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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

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

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

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

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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

Comprehensive analysis of uncertainty quantification for the^(58)Ni(n,p)^(58)Co reaction cross section

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Chinese Physics C 2024年第9期48卷 170-175页

作者： Mahesh Choudhary Aman sharma Namrata singh Mahima Upadhyay Punit Dubey A.gandhi Akash Hingu g Mishra sukanya De L.s.Danu Ajay Kumar R.g.Thomas saurav sood sajin Prasad s.Mukherjee I.N.Ruskov Yu.N.Kopatch A.Kumar Department of Physics Banaras Hindu UniversityVaranasi 221005India Horia Hulubei National Institute of Physics and Nuclear Engineering-IFIN-HH Bucharest 077125Romania Department of Physics The Maharaja Sayajirao University of BarodaVadodara 390002India Nuclear Physics Division Bhabha Atomic Research CentreMumbai 400085India Health Physics Division Bhabha Atomic Research CentreMumbai 400085India Department of Electrical Power Engineering Brno University of TechnologyBrno 61600Czech Republic Institute for Nuclear Research and Nuclear Energy Bulgarian Academy of SciencesSofia 1784Bulgaria Joint Institute for Nuclear Research(JINR) Dubna 141980Russia

In this study,we measured the^(58)Ni(n,p)^(58)Co reaction cross section with neutron energies of 1.06,1.86,and 2.85 *** cross section was measured using neutron activation techniques andγ-ray spectroscopy,and it was compared with cross section data available in the ***,we calculated the covariance matrix of the measured cross section for the aforementioned nuclear *** uncertainties of the theoretical calculation for^(58)Ni(n,p)^(58)Co reaction cross section were calculated via Monte Carlo *** this study,we used uncertainties in the optical model and level density parameters to calculate uncertainties in the theoretical cross *** theoretical calculations were performed by using *** this study,we aim to analyze the effect of uncertainties of the nuclear model input as well as different experimental variables used to obtain the values of reaction cross section.

关键词： ^(58)Ni(n p)^(58)Co reaction γ-ray spectroscopy uncertainty quantification of cross section covariance analysis

Radioisotope production using lasers:From basic science to applications

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Matter and Radiation at Extremes 2024年第3期9卷 31-44页

作者： M.R.D.Rodrigues A.Bonasera M.scisciò J.A.Pérez-Hernández M.Ehret F.Filippi P.L.Andreoli M.Huault H.Larreur D.singappuli D.Molloy D.Raffestin M.Alonzo g.g.Rapisarda D.Lattuada g.L.guardo C.Verona Fe.Consoli g.Petringa A.McNamee M.La Cognata s.Palmerini T.Carriere M.Cipriani g.Di giorgio g.Cristofari R.De Angelis g.A.P.Cirrone D.Margarone L.giuffrida D.Batani P.Nicolai K.Batani R.Lera L.Volpe D.giulietti s.Agarwal M.Krupka s.singh Fa.Consoli Cyclotron Institute Texas A&M UniversityCollege StationTexas 77840USA Laboratori Nazionali del sud Istituto Nazionale di Fisica Nucleare(LNS-INFN)CataniaItaly ENEA Fusion and Technologies for Nuclear Safety and Security Department-CFrascatiItaly Centro de Láseres Pulsados(clpu) VillamayorSpain Universidad de salamanca SalamancaSpain Centre Lasers Intenses et Applications(CELIA) Universitéde BordeauxCNRSCEATalenceFrance HB11 Energy Holdings Pty FreshwaterNew South WalesAustralia school of Mathematics and Physics Queen’s University BelfastBelfastUnited Kingdom Dipartimento di Fisica e Astronomia“E.Majorana ”Università di CataniaCataniaItaly Facoltàdi Ingegneria e Architettura Universitàdegli Studi di Enna“Kore”EnnaItaly Dipartimento di Ingegneria Industriale Universitàdi Roma“Tor Vergata”RomaItaly Dipartimento di Fisica e geologia Universitàdegli Studi di PerugiaPerugiaItaly Istituto Nazionale di Fisica Nucleare Sezione di PerugiaPerugiaItaly ELI Beamlines Facility the Extreme Light Infrastructure ERICDolni BrezanyCzech Republic ETsIA Universidad Politécnica de MadridMadridSpain Dipartimento Fisica “E.Fermi”Universitàdi Pisa and INFNPisaItaly FZU–Institute of Physics of Czech Academy of sciences PragueCzech Republic Institute of Plasma Physics of Czech Academy of sciences PragueCzech Republic

The discovery of chirped pulse amplification has led to great improvements in laser technology,enabling energetic laser beams to be compressed to pulse durations of tens of femtoseconds and focused to a few *** with energies of tens of MeV can be accelerated using,for instance,target normal sheath acceleration and focused on secondary *** such conditions,nuclear reactions can occur,with the production of radioisotopes suitable for medical *** use of high-repetition lasers to produce such isotopes is competitive with conventional methods mostly based on *** this paper,we study the production of^(67)Cu,^(63)Zn,^(18)F,and^(11)C,which are currently used in positron emission tomography and other *** the same time,we study the reactions^(10)B(p,α)^(7)Be and^(70)Zn(p,4n)^(67)ga to put further constraints on the proton distributions at different angles,as well as the reaction^(11)B(p,α)^(8)Be relevant for energy *** experiment was performed at the 1 PW laser facility at VegaⅢin salamanca,*** distributions of radioisotopes in the forward(with respect to the laser direction)and backward directions were measured using a high purity germanium *** results are in reasonable agreement with numerical estimates obtained following the approach of Kimura and Bonasera[*** ***.,sect.A 637,164–170(2011)].

关键词： purity estimates backward

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 withinυs 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

Beyond the Rex: an innovative meso-intrahepatic portal vein bypass for late-onset extrahepatic portal vein occlusion after living donor liver transplantation

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Hepatobiliary surgery and Nutrition 2024年第4期13卷 662-668页

作者： Chee-Chien Yong Hsu-Ting yen Yu-Fan Cheng Leona Bettina Dungca Raymond Joseph De Vera Itsuko Chih-Yi Chen Chao-Long Chen Department of surgery Liver Transplantation CenterKaohsiung Chang Gung Memorial HospitalChang Gung University College of MedicineKaohsiung Department of Cardiovascular surgery Liver Transplantation CenterKaohsiung Chang Gung Memorial HospitalChang Gung University College of MedicineKaohsiung Department of Diagnostic Radiology Liver Transplantation CenterKaohsiung Chang Gung Memorial HospitalChang Gung University College of MedicineKaohsiung

The Meso-Rex bypass(MRB)is recognized as an effective treatment for portal hypertension secondary to extrahepatic portal vein occlusion(EHPVO)both in the pediatric and adult population,within or outside the context of liver *** is the preferred surgical treatment in most centers because not only does it addresses the portal hypertension,but also restores physiologic portal hepatopetal ***,the Rex recess,the landmark for this technique,may not be safely accessible in some *** present a 22-year-old male who underwent living donor liver transplant(LDLT)for neonatal *** presented with variceal bleeding due to EHPVO at 13 years after *** endoscopic,radiologic,and surgical interventions were employed to address the recurrent gastrointestinal bleeding,but results have been *** performed a meso-intrahepatic portal vein bypass(MIPVB),an innovative alternative to the MRB,for this patient with extensive post-operative adhesions,perihilar collaterals,and cavernous *** creation in patients where the Rex recess is inaccessible is technically *** with a multidisciplinary team approach,meticulous preoperative planning,and close follow-up,the authors have demonstrated that it is a safe and feasible option for patients with late-onset EHPVO after liver transplantation.

关键词： Meso-Rex bypass(MRB) portal vein occlusion liver transplantation(LT)