Carbon and oxygen isotope geochemistry of Ediacaran outer platform carbonates, Paraguay Belt, central Brazil

Após a glaciação do final do Criogeniano, a região central do Brasil foi palco de extensa deposição de carbonatos plataformais do Grupo Araras. Este grupo inclui na sua base uma seqüência de capa carbonática sucedida por depósitos transgressivos de calcilutitos betuminosos e folhelhos de plataforma profunda. Dados de fácies e estratigráficos combinados com análises isotópicas de carbono e oxigênio da seção mais completa desses depósitos transgressivos, expostos no sinclinal da Guia, foram empregados para avaliar o paleambiente deposicional e para testar a correlação desses depósitos ao longo da faixa e também com outras unidades de outros continentes. A sucessão estudada consiste de 150 m de espessura de camadas tabulares de calcilutitos e folhelhos cinza a pretos com valores de d13CPDB negativos, entre -2,5 e -1 . O perfil de d13CPDB do sinclinal da Guia mostra clara correlação com a porção superior da Formação Guia da região de Cáceres, 200 km a sudoeste. O perfil de d13CPDB do Grupo Araras é comparável aos perfis de d13CPDB de outras unidades ediacaranas da parte sul da Faixa Paraguai, oeste do Canadá, e crátons do Congo e do Kalahari. Além disso, a distribuição de fácies, estratigrafia e o perfil isotópico do Grupo Araras são equiparáveis à porção média do Subgrupo Tsumeb na Namíbia, o que reforça a atribuição de idade Ediacarana para o Grupo Araras.

Interstitial oxygen's influence on the corrosion behavior of Ti-9Mo alloys

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The Positive Effects of Priming Exercise on Oxygen Uptake Kinetics and High-Intensity Exercise Performance Are Not Magnified by a Fast-Start Pacing Strategy in Trained Cyclists

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

DFT Study on Ce-Doped Anatase TiO2: Nature of Ce3+ and Ti3+ Centers Triggered by Oxygen Vacancy Formation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of Oxygen Content and Microstructure on the Mechanical Properties and Biocompatibility of Ti-15 wt%Mo Alloy Used for Biomedical Applications

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The Influence of Small Quantities of Oxygen in the Structure, Microstructure, Hardness, Elasticity Modulus and Cytocompatibility of Ti-Zr Alloys for Dental Applications

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

In Vitro Cytotoxicity of a Ti-35Nb-7Zr-5Ta Alloy Doped with Different Oxygen Contents

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The effects of different inspired oxygen fractions on gas exchange and Tei-index of myocardial performance in propofol-anesthetized dogs

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Tailoring Thermal Transport Property of Graphene through Oxygen Functionalization

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Two levels of the inspired oxygen fraction in propofol-anesthetized dogs with high intracranial pressure: cardiopulmonary function

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Oxygen Atom Transfer Reactions from Mimoun Complexes to Sulfides and Sulfoxides. A Bonding Evolution Theory Analysis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Reduced levels of intracellular reactive oxygen species and apoptotic status are not correlated with increases in cryotolerance of bovine embryos produced in vitro in the presence of antioxidants

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estudo fotodinâmico da clorofila a, azul de metileno e rosa bengala como agente inseticida contra Aedes aegypti

Photodynamic therapy, term introduced by von Tapeiner in 1900, can be defined as the administration of a non toxic drug, i.e., a dye, known as photosensitizer (FS), which subsequently will be illuminated with light of specific wavelength. PDT is based on the interaction among FS, oxygen and light, which through photochemical reactions cause cell death. The FS molecules must have a high probability to form the singlet state after the excitation, which can induce chemical changes in the neighborhood in two ways, called reactions type I and type II. The type II reaction is based on the exchange of energy to molecular oxygen, exciting it to its state of higher energy (singlet), which is highly reactive. The proposed mechanisms for cell death are linked to damage to the DNA, mitochondria and to the cytoplasmic membrane. Several pre‐clinical and clinical trials have been carried out and the PDT is already used in many countries for treatment mainly against certain types of cancer. The therapy also has been gaining strength in antimicrobial control, since the microorganisms have appeared increasingly resistant to current antibiotics. Another attempt to use the PDT is for the inactivation of macro‐organisms, such as micro‐crustaceans and mosquitoes. To this end I tested whether the photosensitizers methylene blue, rose Bengal and the chlorophyll a has insecticidal activity against the yellow fever and dengue vector mosquito, Aedes aegypti. Since these diseases have no effective treatments, its control is linked to the vector control, which has shown resistance to chemical pesticides used. Based on this, this work shows its importance, because it is a new type of mosquito control since all the photosensitizers used are low cost, do not generate toxic products at the concentrations used and showed good results in mortality. The best photosensitizer was rose Bengal... (Complete abstract click electronic access below)