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Tree encroachment into savannas alters soil microbiological and chemical properties facilitating forest expansion

Journal of Forestry Research 2016年第5期27卷 1047-1054页

作者： Davi rodrigo Rossatto Everlon Cid Rigobelo Departamento de Biologia Faculdade de Ciencias Agrairias e veterinàrias Univ. Estadual Paulista UNESP Via de Acesso Prof. Paulo Donatto Castellane S/N Vila IndustrialJaboticabal - SP 14884-900 Brazil Departamento de Producao Vegetal Faculdade de Ciencias Agrairias e Veterinarias Univ. Estadual Paulista UNESP Viade Acesso Prof. Paulo Donatto Castellane S/N VilaIndustrial Jaboticabal - SP 14884-900 Brazil

Abstract Forests have been expanding over typical savanna sites for the past 3000 years in the Neotropics. Such invasion can produce a series of environmental modifications on typical savanna; however, it remains unclear how modifications in soil properties, caused by the encroachment of woody species, facilitate the expansion of forest ecosystems under dystrophic conditions. Here we examined chemical and microbiological changes associ- ated with tree encroachment in oxisols of a Neotropical Savanna at Assis Ecological Station, Southeastern Brazil. We predicted that tree encroachment caused by typical forest species would cause significant changes in the chemical and microbiological properties of savanna soils. Soils were sampled at Assis Ecological Station, from savanna sites differing in tree encroachment （typical, dense and forested savanna） caused by decades of fire exclusion. We analysed vegetation leaf area index and leaf litter volume deposited in the studied plots and chemical （pH,organic matter, P, K, Ca, Mg, A1, NO3-, NH4＋） and microbiological （microbial C biomass and dehydrogenase activity） properties of soils under distinct encroachment conditions. Most soil chemical properties did not change along the tree encroachment gradient; however, total P, soil organic matter, soil microbial C and dehydrogenase activity increased from typical savanna to forested savanna. The changes in soil organic matter and dehydrogenase activity were correlated with the values of leaf area index and litter volume along the encroachment gradient. Our results demonstrate that forest species can increase carbon and phosphorus supplies in tropical savanna soils.

关键词： Dystrophic Encroachment - Forest - Litter Microbiological activity

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On water security, sustainability, and the water-food-energy-climate nexus

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Frontiers of Environmental Science & Engineering 2013年第5期7卷 626-639页

作者： Michael Bruce BECK rodrigo VILLARROEL WALKER Wamell School of Forestry and Natural Resources University of Georgia Athens GA 30602-2152 USA

The role of water security in sustainable development and in the nexus of water, food, energy and climate interactions is examined from the starting point of the definition of water security offered by Grey and Sadoff. Much about the notion of security has to do with the presumption of scarcity in the resources required to meet human needs. The treatment of scarcity in mainstream economics is in turn examined, therefore, in relation to how each of us as individuals reconciles means with ends, a procedure at the core of the idea of sustainable development. According to the Grey-Sadoff definition, attaining water security amounts to achieving basic, single- sector water development as a precursor of more general, self-sustaining, multi-sectoral development. This is con- sistent with the way in which water is treated as ＂first among equals＂, i.e. privileged, in thinking about what is key in achieving security around the nexus of water, food, energy and climate. Cities, of course, are locations where demands for these multiple resource-energy flows are increasingly being generated. The paper discusses two important facets of security, i.e., diversity of access to resources and services （such as sanitation） and resilience in the behavior of coupled human-built-natural systems. Eight quasi-operational principles, by which to gauge nexus security with respect to city buildings and infrastructure, are developed.

关键词： cities as forces for good diversity energy and nutrient recovery green economy infrastructure failure,resilience

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Nexus security： governance, innovation and the resilient city

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Frontiers of Environmental Science & Engineering 2013年第5期7卷 640-657页

作者： Michael Bruce BECK rodrigo VILLARROEL WALKER Wamell School of Forestry and Natural Resources University of Georgia Athens GA 30602-2152 USA

Nexus security is a compound mix of ideas： reconciling human needs and wants with access to multiple resources; diversity of access to those resources and services; resilience in the face of weather- and climate- related variability; resilience likewise in the face of infrastructure failure; and the personal, individual sense of belonging. At the level of Systems Thinking there is a very close relationship between resilience in the behavior of natural （ecological） systems and resilience in the social dynamics of governance within communities, where such resilience establishes the viability of these communities over centuries, which in turn entails successful stewardship of the man-environment relationship. We use insights from this cross-system mapping -- across natural, built, and human systems -- to assess, first, the role of city governance in achieving nexus security （or not） and, second, the role of technological innovations in serving the same purpose. More specifically, eight principles, covering resilience and diversity of access to resources and services, are used to gauge security-enhancing features of city buildings and infrastructure. Case studies include new designs of resilient office blocks, nutrient （nitrogen and phosphorus） recovery systems for sanitation and waste- water treatment, and the reconstruction of urban parks for the provision of ecosystem services. Throughout the paper, matters of risk in the face of meteorological variability are prominent. We do not conclude, however, that the presence of risk implies nexus insecurity.

关键词： cities as forces for good climate variability,ecosystem services energy and nutrient recovery infrastructure failure urban metabolism

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Genetic variation of sand flies(Diptera:Psychodidae)in Gampaha and Kurunegala districts of Sri Lanka:Complementing the morphological identification

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Asian Pacific Journal of Tropical Medicine 2022年第7期15卷 322-331页

作者： Tharaka Wijerathna Nayana Gunathilaka Wasana rodrigo Department of Parasitology Faculty of MedicineUniversity of KelaniyaRagamaSri Lanka Department of Zoology Faculty of Natural SciencesThe Open University of Sri LankaNawalaNugegodaSri Lanka

Objective:To identity the variation of sand flies in the Gampaha and Kurunegala districts of Sri Lanka and to assess DNA barcoding as a complementing method for morphological ***:A total of 38441 sand flies were collected from selected localities in Gampaha and Kurunegala districts using standard entomological techniques from May 2017 to December *** were identified using morphological features and compared with mitochondrial cytochrome C oxidase subunitⅠgene-based DNA barcoding as an alternative ***:Morphological and molecular identification confirmed the presence of four species under two genera(Phlebotomus and Sergentomyia).Phlebotomus argentipes was the predominant species,followed by Sergentomyia(S.)punjabensis,*** insularis,and an unidentified Sergentomyia *** argentipes showed a clear genetic differentiation from other *** insularis and *** showed a higher genetic affinity to each other than the unidentified *** unidentified Sergentomyia species is morphologically similar to ***,but differs only in clavate ***:DNA barcoding is an effective technique for the identification of sand *** studies using molecular techniques will improve the knowledge of the cryptic diversity of Sri Lankan sand fly *** a reliable and standardized identification system for sand fly species in Sri Lanka is recommended.

关键词： Morphology Sand fly Identification Barcoding Sequencing

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Manipulation of parasite load induces significant changes in the structural-based throat color of male iberian green lizards

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Current Zoology 2018年第3期64卷 293-302页

作者： rodrigo MEGiA-PALMA Javier martinEZ Santiago MERINO Dept Ecologia Evolutiva Museo Nacional de Ciencias Naturales-CSIC J. Gutierrez Abascal 2 E-28006 Madrid Spain Area Parasitologia Dept Biomedicina y Biotecnologia Area de Parasitologia. Facultad de Farmacia Universidad de Alcala de Henares Alcala de Henares E-28871 Madrid Spain

The honesty of structural-based ornaments is controversial. Sexual selection theory predicts that the honesty of a sexual signal relies on its cost of production or maintenance. Therefore, environmental factors with negative impact on individuals could generate high costs and affect the expres- sion of these sexual signals. In this sense, parasites are a main cost for their hosts. To probe the effect of parasites on the structural-based coloration of a lacertid species Lacerta schreiberi, we have experimentally removed ticks from a group of male Iberian green lizards using an acaricide treatment （i.e., the broad-use insecticide fipronil）. All individuals were radio-tracked and recaptured after 15 days to study changes in coloration in both the ultraviolet （UV）-blue （structural-based） and UV-yellow （structural and pigment-based） ornamentations after manipulation, as well as changes in endoand ectoparasitic load and body condition. Additionally, after the experiment, we measured the skin inflammatory response to a mitogen. The fipronil treatment was effective in reducing ticks and it was associated with a significant reduction of hemoparasite load. Throughout the season, individuals treated with fipronil tended to maintain the brightness of the UV-blue throat coloration while control lizards tended to increase it. However, individuals treated with fipronil that were not infected with hemoparasites significantly reduced the brightness of the UV-blue throat color ation. Individuals with a higher initial tick load exhibited a lower UV saturation increment （UV-blue） and a higher brightness increment （UV-yellow） during the experiment. Overall these results experimentally support the idea that parasites adversely influence the expression of the structural-based coloration of male Iberian green lizards. This adds evidence to the hypothesis that sexual ornaments in lizards function as honest signals.

关键词： animal communication ectoparasites Hamilton & Zuk structural-coloration.

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Oligo-carrageenan kappa increases C, N and S assimilation, auxin and gibberellin contents, and growth in Pinus radiata trees

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Journal of Forestry Research 2015年第3期26卷 635-640页

作者： Silvia Saucedo rodrigo A. Contreras Alejandra Moenne University of Santiago of Chile Santiago Chile Facultad de Ciencias Agrarias Universidad Te'cnica Estatal de Quevedo 63 Quevedo Ecuador

Oligo-carrageenans （OCs） obtained from pure carrageenans extracted from marine red algae stimulate growth by enhancing photosynthesis and basal metabolism in tobacco plants and Eucalyptus trees. In addition, OCs stimulate secondary metabolism, increasing the level of metabolites involved in defense against pathogens. In this work, we analyzed the effect of OC kappa on the increase in height, in activities of basal metabolism enzymes in- volved in carbon, nitrogen and sulphur assimilation, ribu- lose 1,5 biphosphate carboxylase/oxygenase （rubisco）, glutamate dehydrogenase （GDH） and O-acetylserine thiol- lyase （OASTL）, and in the level of growth-promoting hormones, the auxin indole acetic acid （IAA） and the gibberellin GA3, in pine （Pinus radiata） trees treated with OC kappa at concentrations of 1 and 5 mg mL-1 and cultivated for 9 months without additional treatment. Pines treated with OC kappa at 1 mg mL-1 showed a similar increase in height but displayed a higher increased in total chlorophyll, activities of rubisco, GDH and OASTL and level of IAA and GA3 than those treated with OC kappa at 5 mg mL-1. Thus, OC kappa stimulates growth and basal metabolism and increases the level of growth-promoting hormones in pine trees, mainly at 1 mg mL-1.

关键词： Auxin Basal metabolism C, N and Sassimilation Gibberellin Oligo-carrageenan kappaPinus radiata

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Sm-Nd systematics of metaultramafic-mafic rocks from the Arroio Grande Ophiolite(Brazil): Insights on the evolution of the South Adamastor paleo-ocean

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Geoscience Frontiers 2020年第6期11卷 2287-2296页

作者： rodrigo Chaves Ramos Edinei Koester Daniel Triboli Vieira Programa de Pòs-Graduação Em Geociências Instituto de GeociênciasUniversidade Federal Do Rio Grande Do Sul.PO Box 1500191501-970Porto AlegreRSBrazil Departamento de Geologia Universidade Federal Do Rio Grande Do Sul.Bento Gonçalves Avenue950091540-000Porto AlegreRSBrazil

In this contribution we present new insights on the evolution of the Dom Feliciano Belt,southernmost Mantiqueira Province,integrating new whole-rock Sm-Nd isotopic data for the Arroio Grande Ophiolite(Punta del Este Terrane,Brazil/Uruguay border)with previously published bulk-rock and isotope geochemistry of the South Adamastor paleo-ocean metamafic rocks located in Uruguay(Paso del Dragon Complex,Punta del Este Terrane)and Namibia(Chameis Subterrane,Marmora Terrane,Gariep Belt).For the regional geology,the new data corroborate previous hypothesis and demonstrate the depleted mantle features of the amphibolites and metagabbros of the studied *** Arroio Grande Ophiolite rocks are compared with its Uruguayan and Namibian counterparts,demonstrating their isotopic and geochemical similarities and differences,and the backarc affinity of the South Adamastor *** MORB-affinity amphibolites from the Arroio Grande Ophiolite-Paso del Dragon Complex are,so far,the most juvenile rocks in the eastern sector of the Dom Feliciano Belt,yielding εNd(640)Ma)between+7.3 and+9,and high 147Sm/144Nd(>0.169)and 143Nd/144Nd(640 Ma)ratios(0.51219-0.51229).The South Adamastor is interpreted in this paper as an internal back-arc ocean,with limited lateral extension,opened at around 750-650 Ma as the result of the closure of the older Charrua-Goianide paleoocean during the Brasiliano/Pan-African orogenic cycle and final configuration of the West Gondwana paleocontinent.

关键词： West Gondwana Brasiliano orogenic cycle Adamastor ocean

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Misfolded amyloid-βstrains and their potential roles in the clinical and pathological variability of Alzheimer’s disease

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Neural Regeneration Research 2023年第1期18卷 119-120页

作者： Sara Kelley Nelson Perez-Urrutia rodrigo Morales Department of Neurology University of Texas Health Science Center at HoustonHoustonTXUSA Centro Integrativo de Biologia y Quimica Aplicada(CIBQA) Universidad Bernardo O’HigginsSantiagoChile

Potential causes for the clinical and pathological variability observed in Alzheimer’s disease(AD):AD is an age-related neurodegenerative disorder characterized by the impairment of cognitive functions such as memory,learning,and *** commonly described clinical symptoms are due to particular pathological changes in the brain,including inflammation,synaptic loss,and neuronal *** changes are a consequence of the accumulation of abnormally folded amyloid-β(Aβ)and tau proteins in specific areas of the central nervous *** the progressive aging of the world’s population,the number of people affected by AD is expected to substantially and consistently increase in the coming *** positions AD as one of the main public health challenges in the near future.

关键词： clinical Alzheimer amyloid

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A Parameter-Space Analysis of the Rikitake System

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Chinese Physics Letters 2013年第12期30卷 13-16页

作者： rodrigo A.da Silva Paulo C.Rech Departamento de Física Universidade do Estado de Santa Catarina89219-710 JoinvilleBrazil

We investigate analytically and numerically the dynamics of the Rikitake *** Routh–Hurwitz criterion is used to study the stability of the equilibrium points of the differential equation system model,as functions of two *** dynamics of the model are numerically studied using diagrams that associate colors to the largest Lyapunov exponent value,in two-dimensional parameter ***,phase-space plots and bifurcation diagrams are used to distinguish periodic and chaotic attractors.

关键词： bifurcation exponent chaotic

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Improving the classifcation accuracy using biomarkers selected from machine learning methods

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Control Theory and Technology 2021年第4期19卷 538-543页

作者： Linduni M.rodrigo Ashoka D.Polpitiya Department of Mathematics and Statistics University of SydneySydneyNSW 2006Australia Colombo School of Business and Management ColomboSri Lanka

High-dimensional data encountered in genomic and proteomic studies are often limited by the sample size but has a higher number of predictor *** selecting the most relevant variables that are correlated with the outcome variable is a crucial *** paper describes an approach for selecting a set of optimal variables to achieve a classifcation model with high predictive *** work described using a biological classifer published elsewhere but it can be generalized for any application.

关键词： Classifcation Variable selection Reversal Regression

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