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Toxoptera citricidus (Kirkaldy,1907) (HEMIPTERA : APHIDIDAE) : aspectos biológicos e respostas às ações de bioinseticidas
(Universidade Federal de São Carlos, 2015-09-11) Gambarra, Wanessa Porto Tito; Silva, Carlos Roberto Sousa e; https://lattes.cnpq.br/4890369735136839; https://lattes.cnpq.br/4534870573184434
Aphids are important pests in agriculture, mainly because they are vectors of phyto-pathogenic virus. One of the ways to control these insects, is the use of botanical insecticides. However in order to the control to be effective it is also necessary to know their biological characteristics. In this context, the aim of the present study was to evaluate the bioactivity of several plant extracts upon Toxoptera citricidus, presently considered one of the most important pests of citric plantations. For this purpose its life cycle has been studies and important metabolic processes as: consumption, production, respiration and excretion were quantified. Based on these data the species life table and energy budget were constructed. The bioactivity of 11 species of plants including a nanoformulation of the neen, Azadirachta indica, was evaluated through acute toxicity tests. T. citricidus was maintained on Citrus limonia under controlled constant conditions in the laboratory. Among these 5 had insecticide activity upon T. citricidus causing mortality to 80 % of the individuals tested or more. The lethal median concentration (CL50 48h) varied from 0.17 to 4.10 mg/mL for the nynphal phases and from 0.30 to 5.01 mg/mL to adults thus evidencing insecticide properties and presenting high to be used in the management of this pest. A magnetic nuclear ressonance of honeydew, the excretion product of this aphid, evidenced the presence of important aminoacids besides carbohydrates allowing an advance in the knowledge on aphid-ants and aphid- host plant. The total energy budget of of T. citricidus varied According to the aphid age. Mean daily energy consumption were 0.3717 cal for nymphs and 0.4761cal for adults. The energy fraction invested in production by T. citricidus was high, with a mean value around 60%, evidencing high efficiency of energy retention. It was concluded that considering its biological characteristics T. citricidus has a relevant role in the energy transference across the ecosystem.
Complexos mono, bi e trinucleares de metais de transição com bases de Schiff tridentadas tipo ONN e tetradentadas do tipo ONNO : síntese, caracterização e estudos como catalisadores na oxidação de catecois
(Universidade Federal de São Carlos, 2015-09-11) Silva, Ricardo Soares Mota; Dockal, Edward Ralph; https://lattes.cnpq.br/6461328124491559; https://lattes.cnpq.br/7666959621410912
Salen-type complexes are an important class of coordination compounds, which have been used to catalyze a wide variety of reactions in various homogeneous and heterogeneous systems. Complexes of transition metals are very versatile and participate in many chemical processes, which make the study of these very interesting. Research shows that the complexes of salen [salen = N, N'-ethylenebis (salicilidenoamina)] are efficient catalysts, and some compounds of this type have been investigated as catalysts in the oxidation of catechol. In this work were synthesized six types of compounds, ligands, symmetric mononuclear complexes, tridentate complexes, asymmetric mononuclear complexes, binuclear and trinuclear complexes. The series have satisfactory yields. The synthesized compounds in this work were characterized by melting point, elemental analysis, vibrational spectroscopy in the IR region, absorption spectra in the UV-vis, conductivity measurements and solubility. The ligands and three palladium(II) complexes were also characterized by nuclear magnetic resonance. From these characterizations, comparisons were made between ligands, mononuclear, tridentate, binuclear and trinuclear complexes, and also with respect to the effects of the substituents on the aromatic ring at positions 4 and 5. The kinetics was performed using a spectrophotometer, following the formation of the product derived from oxidation of 3,5-di-tert-butylcatechol at 400 nm. In kinetic study were tested the binuclear and the trinuclear complexes which showed catalytic activities compatible with those of similar complexes described in the literature, among them we can mention the binuclear complexes [Cu(Cu(t-4DEA-salcn))Cl2] e [Cu(Cu(t-5NO2- salcn))Cl2] , kcat = 0,132 s-1 e kcat = 0,108 s-1, respectively; and the palladium(II) copper(II) binuclear complexes [Cu(Pd(t-salcn))Cl2] e [Cu(Pd(t-4-DEA-salcn))Cl2], kcat = 0,113 s-1 e kcat = 0,240 s-1, respectively.
Análise de predação intraguilda em alfafa
(Universidade Federal de São Carlos, 2015-09-11) Iemma, Luis Gustavo Rodrigues; Sousa e Silva, Carlos Roberto; https://lattes.cnpq.br/4890369735136839; https://lattes.cnpq.br/1043228491783390
Aphids are considered as pests in several crops causing direct and indirect damage to the plants. In alfalfa fields (Medicago sativa), the species Acyrthosiphon pisum, Acyrthosiphon kondoi, Aphis craccivora and Therioaphis trifolii are found very often. Their natural enemies include predators and parasitoids among others. The aim of this work was to analyze the seasonal fluctuation of aphid populations and its relationship with climatic variables through correlation tests; in laboratory, to select the aphid species which were abundant in the field, having parasitoids and coccinelids predators associated with the intention of using them in serologic tests aiming to observe a possible intraguild predation. The serological technique is based on reactions as antigen/antibody where the antibodies are obtained to the specie of interest. The gathering of aphids, predators and parasitoids occurred from March 2013 to May 2014 in experimental alfalfa crioula fields located at Embrapa Pecuária Sudeste Unit, São Carlos, SP. Therioaphis trifolii was the most abundant aphid during the sampling period, followed by Acyrthosiphon pisum. Considering all species the populational peak occurred in September 2013 and the lower in January 2014. According to the tests, all species had no correlation with the rain, and no other variable presented significant influence in aphid’s seasonal fluctuation. 1208 coccinelids (Coleoptera: Coccinellidae) of six species were sampled and the three with more specimens, Harmonia axyridis, Hippodamia convergens and Cycloneda sanguinea respectively, were separated to be part of the serological tests. A typical pattern predator-prey was observed. No species of parasitoids were found in T. trifolii and one species of parasitoid, Aphidius ervi (Hymenoptera: Aphidiidae) was found on A. pisum, and this led to its choice to the intraguild predation tests. According to the serological tests results, 52 among 485 coccinelids tested had traces of the parasitoid in its gut contents, that means 10,72% of the coccinelids ate parasited aphids. Feeding tests have shown that the parasitoid A. ervi can be detected up to 72 hours after its ingestion.
Construção da parábola através de modelos lúdicos e computacionais
(Universidade Federal de São Carlos, 2015-09-11) Tassone, Márcia Zulian Teixeira; Salvador, José Antonio; https://lattes.cnpq.br/2487171069472158
Technological development is associated with systematic and organized knowledge, gathered during the entirety of human existence. The conics, in particular, the parabola, have a relevant presence in this development, although its study in basic education has been restrained to the manipulation of formulas without a context. This dissertation discusses the development of diverse activities related to the teaching of the parabola with the goal of relating theory and practice through its use in an academic context. This project was initially designed and developed for one class in their third year of high school at a public institution in Brazil. In order to introduce the characteristics and properties of the parabola, the use of physical and entertaining activities such as paper folding, along with resources from the geometrical environment, especially the program GeoGebra, were put to use to in order to achieve investigation, data analysis, a search for regularities, and identification and validation of the mathematical models. The diverse activities motivated the students to build a parabolic solar stove, which helped to connect theory and practice. In a second phase of experiment, the activities were applied in another public school, with the goal of involving a larger corpus of students within the fields of mathematics and the natural sciences. The activities developed used parabolic objects for reflection of sound waves and led to the elaboration of a project to build a parabolic bench in the school’s garden. It also presents a short analysis of the teaching and learning processes, based on the hypotheses of Piaget and Paulo Freire, about the role that mathematics has in human development and the aspects of mathematics education that utilize investigative processes and modeling. It was perceived the efficiency on the development of the competencies and abilities required nowadays and its viability to the realization of the scholarly activities.