1,137 research outputs found
Reconstructing fluvial bar surfaces from compound cross-strata and the interpretation of bar accretion direction in large river deposits
The interpretation of fluvial styles from the rock record is based for a significant part on the identification of different types of fluvial bars, characterized by the geometric relationship between structures indicative of palaeocurrent and surfaces interpreted as indicative of bar form and bar accretion direction. These surfaces of bar accretion are the boundaries of flood-related bar increment elements, which are typically less abundant in outcrops than what would be desirable, particularly in large river deposits in which each flood mobilizes large volumes of sediment, causing flood-increment boundary surfaces to be widely spaced. Cross-strata set boundaries, on the other hand, are abundant and indirectly reflect the process of unit bar accretion, inclined due to the combined effect of the unit bar surface inclination and the individual bedform climbing angle, in turn controlled by changes in flow structure caused by local bar-scale morphology. This work presents a new method to deduce the geometry of unit bar surfaces from measured pairs of cross-strata and cross-strata set boundaries. The method can be used in the absence of abundant flood-increment bounding surfaces; the study of real cases shows that, for both downstream and laterally accreting bars, the reconstructed planes are very similar to measured bar increment surfaces.Sao Paulo Research Foundation (FAPESP)CAPESCNPqLiliane JanikianUniv Sao Paulo, Inst Energia & Ambiente, Av Prof Luciano Gualberto 1289,Cidade Univ, BR-05508900 Sao Paulo, SP, BrazilUniv Sao Paulo, Inst Geociencias, Rua Lago 562,Cidade Univ, BR-05508900 Sao Paulo, SP, Brazil|Univ Fed Itajuba, Inst Recursos Nat, Av BPS 1303, BR-37500903 Itajuba, MG, BrazilCPRM Geol Survey Brazil, Rua Costa 55, BR-01304010 Sao Paulo, SP, BrazilUniv Fed Sergipe, Dept Geol, Av Marechal Rondom S-N, BR-49100000 Sao Cristov, SE, BrazilUniv Fed Sao Paulo, Campus Baixada Santista, BR-11030400 Santos, SP, BrazilUniv Fed Sao Paulo, Campus Baixada Santista, BR-11030400 Santos, SP, BrazilFAPESP: 2009/53363-8FAPESP: 2009/52807-0FAPESP: 2009/51766-8FAPESP: 2010/51103-6FAPESP: 2010/51559-0FAPESP: 2013/01825-3FAPESP: 2014/16739-8CAPES: PROEX-558/2011CNPq: 301774/2012-9Liliane Janikian: 301775/2012-5Web of Scienc
Foraminifera as health bioindicators in nearshore and offshore Brazilian coral reef sediments
Abstrac
Ultrafast third-order optical nonlinearities of heavy metal oxide glasses containing gold nanoparticles
This work reports on the third-order nonlinear properties and the response time of GeO2-Bi2O3 glass, as well as the effect of gold nanoparticles on these properties. The nonlinear refractive index spectrum and the nonlinear absorption coefficient were determined by the Z-scan technique, and the response time was obtained through Kerr gate measurements, using femtosecond pulses. The results show that the presence of gold nanoparticles causes a saturable absorption effect that is overcome by the two-photon absorption process at higher light intensities, for wavelengths within the plasmon band. We measured a constant value for the nonlinear refractive index (n2) for the visible and infrared regions, which was not affected by the presence of gold nanoparticles in the sample. However, the n2 value is one order of magnitude higher than the one for fused silica and 1.5 times better than PGO (PbO-GeO2) glasses. In addition, the response time of the induced birefringence for the samples with and without gold nanoparticles is faster than the pulse duration (220 fs), indicating an ultra-fast electronic process.FAPESPCNPqCAPESINCT INF
Valoração de bens e serviços ecossistêmicos associados a projetos de recuperação e conservação ambiental no reservatório de Três Irmãos: carbono, uso público e recursos pesqueiros / Valuation of ecosystem goods and services associated with environmental recovery and conservation projects in the Três Irmãos reservoir: carbon, public use and fishing resources
O objetivo da pesquisa “Metodologia de Valoração de Bens e Serviços Ecossistêmicos Associados a Projetos de Recuperação e Conservação Ambiental em Reservatórios Hidrelétricos” foi estabelecer metodologias adaptadas ao setor hidrelétrico brasileiro, demonstrando que é possível – e necessário – estimar a importância social e econômica das ações de proteção ambiental, com estudo de caso para a UHE Três Irmãos. Para tal, metodologias de valoração ambiental foram aplicadas às ações de conservação conduzidas pelas concessionárias. O presente artigo examina esses benefícios obtidos em termos de balanço de carbono, uso público e recursos pesqueiros. As ações de reflorestamento e de conservação contribuíram para reduzir o volume de carbono na atmosfera. No cenário corrente de reflorestamento, estima-se que o valor do benefício em termos de carbono capturado supere R 60,5 milhões caso o reflorestamento se aproxime do cenário de uma faixa de 250 metros de extensão das margens do reservatório. O VPL desses benefícios foi estimado em R 473,2 milhões até 2027, respectivamente. Estendendo o horizonte de tempo até 2037, o VPL dos benefícios superaria R 736,1 milhões nos cenários supracitados. Outro benefício das ações de conservação ambiental foi a garantia de um grande fluxo de turismo (mais de 500 mil visitantes em 2017), cujos gastos induziram um aumento de mais de R 4 milhões nas receitas das prefeituras
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International meta-analysis of PTSD genome-wide association studies identifies sex- and ancestry-specific genetic risk loci.
The risk of posttraumatic stress disorder (PTSD) following trauma is heritable, but robust common variants have yet to be identified. In a multi-ethnic cohort including over 30,000 PTSD cases and 170,000 controls we conduct a genome-wide association study of PTSD. We demonstrate SNP-based heritability estimates of 5-20%, varying by sex. Three genome-wide significant loci are identified, 2 in European and 1 in African-ancestry analyses. Analyses stratified by sex implicate 3 additional loci in men. Along with other novel genes and non-coding RNAs, a Parkinson's disease gene involved in dopamine regulation, PARK2, is associated with PTSD. Finally, we demonstrate that polygenic risk for PTSD is significantly predictive of re-experiencing symptoms in the Million Veteran Program dataset, although specific loci did not replicate. These results demonstrate the role of genetic variation in the biology of risk for PTSD and highlight the necessity of conducting sex-stratified analyses and expanding GWAS beyond European ancestry populations
Identification of Eschweilenol C in derivative of Terminalia fagifolia Mart. and green synthesis of bioactive and biocompatible silver nanoparticles
A green synthetic route was developed to prepare silver nanoparticles (AgNPs) in aqueous solution for biological applications. Eschweilenol C, a compound derivative ellagic acid was identified as the main constituent of the aqueous fraction of the ethanolic extract of Terminalia fagifolia Mart. by NMR analysis. In the green synthesis, the ethanolic extract of T. fagifolia and its aqueous fraction were used to promote silver reduction and nanoparticle stabilization. The synthesized AgNPs presented a spherical or polygonal morphology shape by TEM analysis and AgNPs showed high levels of antioxidant and considerable antibacterial and antifungal activities. Synthesized nanoparticles presented significant antioxidant activity by sequestration of DPPH and ABTS radicals, in addition to iron reduction (FRAP assay) and measurement of antioxidant capacity in ORAC units, in addition, AgNP synthesized with the aqueous fraction also demonstrated antioxidant potential in microglial cells. Gram-positive and Gram-negative bacteria were susceptible to growth inhibition by the nanoparticles, among which the AgNPs formed by the ethanolic extract was the most effective. The data obtained by AFM images suggested that AgNPs could lead to the lysis of bacteria and subsequent death. The antifungal assays showed high efficiency against yeasts and dermatophytes. This work represents the first description of antifungal activity by AgNPs against Fonsecaea pedrosoi, the etiologic agent of chromoblastomycosis. In relation to biocompatibility, the AgNPs induced lower haemolysis than AgNO3.We thank Herbert Kogler and Reinhard Wimmer for the identification of Eschweilenol C. The NMR laboratory at Aalborg University is supported by the Obel Family, SparNord and Carlsberg foundations.The authors are grateful to Carla Eiras (LIMAV/CT/UFPI) and to FCT and EU for financial support through project UID/QUI/50006/2013– POCI-01-0145-FEDER-007265 from COMPETE and projectNORTE-01-0145-FEDER-000011 from COMPETE. Thanks to Andreia Pinto for help with the TEM measurements at Instituto de Medicina Molecular (IMM). This work was supported by the Histology and Comparative Pathology Laboratory of the IMMinfo:eu-repo/semantics/publishedVersio
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