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Pure and mixed plantations of Persian walnut (Juglans regia L.) for high quality timber production in Chile, South America

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Journal of Plant Ecology 2020年第1期13卷 12-19页

作者： Verónica Loewe-Muñoz Mónica Balzarini Marta ortega González Chilean Forest Institute(INFOR) Metropolitan OfficeSucre 2397ÑuñoaSantiagoChile CONICET Biometry Unit College of AgricultureUniversidad Nacional de CórdobaCiudad UniversitariaCC509CP 5000CórdobaArgentina Chilean Forest Institute(INFOR) Biobío OfficeCamino a Coronel Km 7.5San Pedro de la PazConcepciónChile

Aims Persian walnut(Juglans regia L.),an interesting forest species for the veneering industry,requires adequate management to produce valuable high-quality *** species associations and management level can improve stand productivity,the novelty of this work was to assess Persian walnut performance in different planting mixtures and in pure plantations conditioned to management *** Growth,straightness and survival measurements were taken annually for 7 years after planting pure and mixed plantations under two contrasting management *** were recorded at Age 7 in all *** each management intensity,besides the monoculture,three mixtures were tested:a mixture of only main forest species,main forest species plus one arboreal companion species,Black alder(Alnus glutinosa L.)and main species plus the shrub Russian olive(Elaeagnus angustifolia L.)as nurse species.A test of interaction between plantation type and management scenario was conducted using repeated growth *** Findings The interaction was significant,indicating the presence of different mechanisms underlying plantation effects under high and low management *** with pure plantations,Persian walnut associated with the nurse shrub exhibited 78%higher height and 53%higher diameter growth in plantations under low *** benefits(lower presence of walnut blight than in the monoculture)and better straightness were also found in the association including the shrub when the management intensity was not *** beneficial effects in the presence of Russian olive were not present under high management intensity(irrigation,fertilization,tutoring and frequent pruning).Site-specific designs for Persian walnut plantations would depend on the foreseen management intensity.

关键词： noble wood monoculture forest associations companion species Russian olive

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Partitioning between primary and secondary metabolism of carbon allocated to roots in four maize genotypes under water deficit and its effects on productivity

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The Crop Journal 2015年第5期3卷 379-386页

作者： Alyne Oliveira Lavinsky Paulo Cesar Magalhaes Roniel Geraldo avila Mariana Melo Diniz Thiago Correa de Souza Embrapa Milho e Sorgo Sete LagoasMGCEP:35701-970Brazil Universidade Federal de Lavras LavrasMGCEP 37200-000Brazil Universidade Federal de Sao Joao Del Rey Sete LagoasMGCEP 35701-970Brazil Universidade Federal de Alfenas AlfenasMGCEP 37130-000Brazil

Plants may respond to drought by altering biomass allocation to shoots and roots or by changing the metabolic activities in these organs. To determine how drought changes the partitioning of carbon allocated to growth and secondary metabolism in maize roots and how it affects photosynthesis(A) and productivity in maize, we evaluated leaf gas exchange, yield componentes, root morphology, and primary and secondary metabolites including total soluble sugars(TSS), starch(S), phenolics(PHE), and lignin(LIG). Data were collected from pot-grown plants of four maize genotypes: BRS 1010 and 2B710(sensitive genotypes) and DKB390 and BRS1055(tolerant genotypes) under two soil water tensions: field capacity(FC,-18 kP a) and water deficit(WD,-138 kP a). WD was applied at the pre-flowering stage for 12 days and then the water supply was restored and maintained at optimum levels until the end of the cycle. For genotype BRS 1055 under FC, the greatest A did not result in greater grain biomass(DGB) because the accumulated photoassimilates had already filled the cells, and thus the excessive TSS synthesized in leaves was allocated to roots in large amounts. However, the sharp decrease in A caused by WD imposition in this genotype did not affect the influx pressure of leaf TSS, which was due largely to conversion of primary metabolites to PHE compounds to increase the length of fine roots. In leaves of DKB390 under WD, both S and TSS were reduced, whereas PHE were increased to prevent excessive water loss and xylem cavitation. Under WD, both BRS1010 and2B710 genotypes displayed reduced allocation of biomass to shoots and roots and LIG content in leaves, as well as lower A and DGB values. In BRS1010 this response was coupled to S decrease in leaves and TSS increase in roots, whereas in 2B710 there was a concomitant S increase in roots.

关键词： Starch Sugars Lignin Phenols WinRHIZO

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Global assessment of genetic variation and phenotypic plasticity in the lichen-forming species Tephromela atra

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Fungal Diversity 2014年第1期64卷 233-251页

作者： Lucia Muggia Sergio Pérez-ortega Alan Fryday Toby Spribille Martin Grube Institute of Plant Sciences Karl-Franzens-University GrazHolteigasse 68010 GrazAustria Department of Life Science University of TriesteVia Giorgieri 1034127 TriesteItaly Department of Environmental Biology Museo Nacional de Ciencias Naturales(CSIC)C/Serrano 115-dpdoMadridSpain Department of Plant Biology Michigan State UniversityEast LansingMI 48824-1312USA Division of Biological Sciences University of MontanaMissoulaMT 59812USA

Understanding how many species exist and the processes by which they form remains a central topic of ecological and evolutionary biology,but represents a special challenge within microbial *** lichen-forming fungi represent one of the best examples in which species evolution and diversity create patterns of high phenotypic plasticity coupled with wide geographic *** sampled the lichen-forming species Tephromela atra and related species at a world-wide scale to reconstruct a phylogenetic hypothesis using three nuclear *** were also studied for morphological and chemical traits to assess how well the phenotypic relationships with species,previously segregated from ***,agrees with molecular *** used a genealogical concordance approach and identified 15 monophyletic clades,which may represent independent *** combining morphological and chemical characters,ecological preferences and geographic origin we distinguish six different *** subtle phenotypical traits are frequently used for describing previously cryptic species in fungi,the continuum of variability found in morphology and chemical patterns in *** prevents the description of new taxa with characteristic *** observed that phenotypic characters arise in parallel at local or regional scale but are not correlated with genetic ***,they are insufficient for characterizing species with broad geographic ranges within ***.

关键词： Chemistry Ecology Morphology Multigene phylogeny Phylogeography Symbiosis

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Periodontal research contributions to basic sciences:From cell communication and host-parasite interactions to inflammation and bone biology

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BIOCELL 2022年第3期46卷 633-638页

作者： RAFAEL SCAF DE MOLON ERICA DORIGATTI DE avila JONI AUGUSTO CIRELLI JOAO PAULO STEFFENS Federal University of Rio de Janeiro-UFRJ Rio de Janeiro21941-617Brazil São Paulo State University-UNESP Araraquara14801-930Brazil Federal University of Parana-UFPR Curitiba80210-170Brazil

The periodontium comprises all structures surrounding the teeth,including gingiva,root cementum,periodontal ligament and alveolar *** tissues aim to protect and support the teeth and are challenged by a residing microbiota that leads to subclinical inflammation even in physiological ***,a prevalent multicausal inflammatory and destructive disease,develops as a result from complex host-parasite *** unique physiologic and pathologic scenario enables the development of research methods which allows conclusions beyond the simple understanding of periodontal *** aim of this viewpoint was to explore potential contributions of periodontal research to a wide array of basic science specialties,such as cell and molecular biology,microbiology,immunology,endocrinology,rheumatology,among others.

关键词： Alveolar bone Bone Periodontal disease Rheumatoid arthritis

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Variable-top stem biomass equations at tree-level generated by a simultaneous density-integral system for second growth forests of roble, raulí,and coigüe in Chile

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Journal of Forestry Research 2019年第3期30卷 993-1010页

作者： Carlos Valenzuela Eduardo Acuna Alicia ortega Geronimo Quinonez-Barraza Jose Corral-Rivas Jorge Cancino Departamento Manejo de Bosques y Medio Ambiente Facultad de Ciencias ForestalesUniversidad de Concepcion Victoria 631Barrio Universitario4070386 ConcepcionChile Instituto de Bosques y Sociedad Facultad de Ciencias Forestales y Recursos NaturalesUniversidad Austral de ChileCampus Isla Teja5110566 ValdiviaChile Campo Experimental Valle del Guadiana Instituto Nacional de Investigaciones Forestales Agricolas y Pecuarias (INIFAP)km 4.5 Carretera Durango-Mezquital34170 DurangoDGOMexico Instituto de Silvicultura e Industria de la Madera Universidad de Juarez del Estado de Durango34120 DurangoMexico

Variable-top stem biomass models at the tree level for second growth forests of roble (Nothofagus obliqua), rauli(Nothofagus alpina), and coigüe (Nothofagus dombeyi) were fitted by a simultaneous density-integral system, which combines a stem taper model and a wood basic density model. For each model, an autoregressive structure of order 2 and a power equation of residual variance were incorporated to reduce residual autocorrelation and heteroscedasticity, respectively. By using dummy variables in the regression analysis, zonal effects on the parameters in the variable-top stem biomass equations were detected in roble. Consequently, equations for clusters of zones were obtained. These equations presented significant parameters and a high precision in both fitting and validation processes (i.e., CV<11.5% and CVp<11.9%, respectively), demonstrating that they are unbiased. The advantage of these types of functions is that they provide estimates of volume and biomass of sections of the stem, defined between any two points of the stem in the three species. Thus, depending on the final use of the wood and the dimensions of the tree, a stem fraction can be quantified in units of volume and the remaining fraction in units of weight.

关键词： Autocorrelation Density-integral Dummy variables Autoregressive error structure Heteroscedasticity

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NHC-catalysed[3+2]-asymmetric annulation between pyrazolin-4,5-diones and enals:synthesis of novel spirocyclic pyrazolone γ-butyrolactones and computational study of mechanism and stereoselectivity

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Organic Chemistry Frontiers 2022年第2期9卷 420-427页

作者： Marta Gil-Ordonez Alicia Maestro Pablo ortega Pablo G.Jambrina Jose M.Andres GIR-SintACat-Instituto Universitario CINQUIMA y Departamento de Química Orgánica Facultad de CienciasUniversidad de ValladolidPaseo Belén 747011 ValladolidSpain Departamento de Química Física University of Salamanca37008 SalamancaSpain

Chiral pyrazolones with a spirocyclic centre at the C4-position are widely found in a large family of medically relevant *** recent years,organocatalysis,particularly that performed with quiral N-heterocyclic carbenes(NHCs),has allowed the enantioselective synthesis of these spirocyclic compounds despite its inherent *** this work,we describe the fully diastereo-and highly enantioselective synthesis of novel spirocyclic pyrazolone γ-butyrolactones via NHC-catalysed[3+2]annulation reaction of enals and 1H-pyrazol-4,*** understand the catalytic mechanism and origin of stereoselectivity,electronic structure calculations were carried *** considering various pathways,we concluded that the stereoselectivity-determining step is the formation of the lactone that proceeds after addition of the NHC derived homoenolate to the electrophilic carbonyl group of pyrazolin-4,*** calculations predict that the free energy barrier is lower for the(RS)product,which is also the main product experimentally obtained.

关键词： synthesis spiro mechanism

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Dynamic assessment of variations in pupil diameter using swept‑source anterior segment optical coherence tomography after phakic collamer lens implantation

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Eye and Vision 2021年第6期8卷 396-403页

作者： Felix Gonzalez‑Lopez Carmen Bouza‑Miguens Victor Tejerina Vasyl Druchkiv Blas Mompean Julio ortega‑Usobiaga Rafael Bilbao‑Calabuig Department of Refractive Surgery Clinica BavieraMelchor Fernández Almagro928029 MadridSpain Department of Research and Development Clinica BavieraValenciaSpain

Purpose:To dynamically assess variations in pupil diameter induced by changes in brightness in myopic eyes implanted with an implantable collamer lens(ICL,STAAR Surgical)with a central ***:This prospective,observational single-center case series study comprised 65 eyes from 65 consecutive patients undergoing ICL implant.A modified commercially available swept-source Fourier-domain anterior segment optical coherence tomography(AS-OCT)device was used for imaging and performing dynamic pupillometry under changing light conditions before and after a mean follow-up interval of four months after ***:Preoperative mean pupil size under photopic conditions was 3.38±0.64 mm;after surgery,this increased to 3.48±0.61 *** pupil size under scotopic light conditions was 5.72±0.79 mm before surgery and 5.84±0.77 mm *** differences between preoperative and postoperative pupil diameter in miosis and mydriasis were 0.10±0.44 mm(P=0.078)and 0.12±0.58 mm(P=0.098),*** scotopic pupil exceeded the optic zone of the implanted lens in 39 eyes(60%).The mean central vault value was 412±177μm under maximum miosis and 506±190μm under maximum *** found a positive correlation between vault and differences in pupil diameter under all light conditions(P<0.05).Conclusion:Dynamic AS-OCT enables a very precise determination of the pupillary diameter in the iris *** changes in the pupil diameter under different light conditions after the implantation of an ICL are related to the postoperative vault.

关键词： Phakic collamer lens ICL Pupil OCT Central hole Central port Posterior chamber phakic lens

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Turning carbon dots into selenium bearing nanoplatforms with in vitro GPx-like activity and pro-oxidant activity

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Nano Research 2023年第5期16卷 7784-7791页

作者： Laura Perez-Garrido Mariano ortega-Muñoz Fernando Hernandez-Mateo F.Javier Lopez-Jaramillo Francisco Santoyo-Gonzalez Department of Organic Chemistry Biotechnology InstituteSchool of SciencesCampus Fuentenueva snUniversity of Granada18071-GranadaSpain

Selenium(Se)has been defined as the“Janus element”,with one face showing antioxidant activity and the other pro-oxidant *** biological effect of Se depends on both dose and *** nanoparticles are attracting major interest,although their large-scale preparation for biomedical applications is not *** hypothesize that acid anhydride-coated carbon dots(AACD)are an attractive platform for preparing nanoparticles containing chemically defined *** reaction of AA-CD with 3-selenocyanatopropan-1-amine yields carbon dots bearing selenocyanate and carboxylate groups(CD-SeCN)that allow for tuning the ***-SeCN has a Se content of 0.36μmol per mg of nanoparticles,they show the typical photoluminescence of carbon *** selenocyanate groups(SeCN)exhibited glutathione peroxidase-like activity and *** show that antioxidant behavior differs between normal and tumor cells,the evaluation on HEK293 and A549 cells reveals that the toxicity of CD-SeCN depends on dose,time,intracellular glutathione(GSH)*** toxicity of CD-SeCN decreases with the time of incubation and the cell death mechanism switches from necrosis to apoptosis,indicating that CD-SeCN is ***,high levels of intracellular GSH exert a protective *** results support a pharmacological potential in cancers with low levels of intracellular *** use of AA-CD as nanoplatforms is a general strategy that paves the way for the engineering of advanced nanosystems.

关键词： selenium nanoparticles carbon dots glutathione peroxidase-like activity Janus element nanomedicine

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A Vaccine Is Coming but Prevention Is Still up to Us

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Open Journal of Nursing 2021年第1期11卷 1-6页

作者： Hector ortega Gossamer Bio Inc. Clinical Development San Diego CA USA

Despite having a better understanding of the COVID-19 disease, we are facing significant challenges regarding behaviors that enforce the lack of adherence to public health recommendations including the use of face masks and vaccine acceptability. Lessons learned from the 1918 flu pandemic, highlight the importance of wearing a face mask in conjunction with adherence to other public health recommendations. There are two key factors that influence how our communities are translating scientific evidence, denialism and ignorance. Sadly, a real consequence of this pandemic among a significant number of patients with COVID-19 disease is denial. As health care providers we need to take part in addressing these issues and educate our communities especially during this time where we see a second and larger uptake of COVID-19 cases. Fighting denialism and ignorance represents a significant challenge to our society and could have a substantial positive impact on helping with vaccine acceptability and other public health recommendations.

关键词： COVID-19 Education Denialism Ignorance Pandemic SARS-CoV-2

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Hydrogeochemical and isotopic assessment of the origin of NO_(3)^(−)and N-NH_(3)contents in the aquifer located in a closed lacustrine volcano-sedimentary basin in the metropolitan area of Mexico City

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Acta Geochimica 2024年第4期43卷 719-736页

作者： Jose Ivan Morales-Arredondo Maria Aurora Armienta Hernandez Joel Edmundo ortega-Gutierrez Elisa Cuellar Ramirez Natural Resources Department Institute of GeophysicsNational Autonomous University of MexicoCiudad Universitaria No.3000Col.Copilco UniversidadCoyoacán Delegation04360 MexicoCDMXMexico Instituto Politecnico Nacional ***án 55La Laguna Ticoman07340 MexicoCDMXMexico Benemérita Universidad Autónoma de Puebla Ciudad Universitaria Col.San ManuelPueblaPueMexico

To explain the presence and spatial distribution of NO_(3)^(−)and N-NH_(3)in the Aquifer of the Metropolitan Area of Mexico City(AMAMC),a hydrogeochemical and isotopic analysis using^(13)C DIC(as well as the stable isotopes^(18)O and^(2)H)in groundwater was *** aquifer is located in an old closed lacustrine volcano-sedimentary basin;some wells hosted in the semi-confined zone contain high N-NH_(3)concentrations,while others present NO_(3)^(−)contents in the recharge zones(hosted in an oxidizing environment).In this study,a change in the isotopic signature(primarily in^(18)O and^(2)H)was observed from the recharge zones to the basin center in some of the wells with high NO_(3)^(−)concentrations,this behavior can be attributed to evaporation during the incorporation of recently infiltrated *** addition,the results for^(13)C(along with ^(2) H)in wells with the highest N-NH_(3)concentrations exhibited an atypically broad range of *** indicated the occurrence of hydrogeochemical and/or biochemical processes in the aquifer(in an oxidizing or reducing environment),such as organic degradation,bacterial decomposition(primarily in the ancient Lake Texcoco and which acts as a natural sink for carbon,nitrogen,sulfur,and phosphorus),besides rock weathering and dissolution,which may be responsible for a very marked isotopic modification of the^(13)C(and,to a lesser extent,2 H).Methanotrophic bacterial activity and methanogenic activity may be related to N-NH_(3)removal processes by oxidation and residual water incorporation respectively,whereas the increase in the NO_(3)^(−)content in some wells is due to the recent contribution of poor-quality water due to contamination.

关键词： 18 O and^(13)C isotopes Iron Hydrogeochemical processes Nitrate Nitrogen species

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