Paper-based diffusive gradients in thin films technique coupled to energy dispersive X-ray fluorescence spectrometry for the determination of labile Mn, Co, Ni, Cu, Zn and Pb in river water

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

Using traditional heuristic algorithms on an initial genetic algorithm population applied to the transmission expansion planning problem

This paper analyses the impact of choosing good initial populations for genetic algorithms regarding convergence speed and final solution quality. Test problems were taken from complex electricity distribution network expansion planning. Constructive heuristic algorithms were used to generate good initial populations, particularly those used in resolving transmission network expansion planning. The results were compared to those found by a genetic algorithm with random initial populations. The results showed that an efficiently generated initial population led to better solutions being found in less time when applied to low complexity electricity distribution networks and better quality solutions for highly complex networks when compared to a genetic algorithm using random initial populations.

TWO DECOMPOSITION APPROACHES APPLIED TO THE MULTI-AREA OPTIMAL REACTIVE POWER FLOW PROBLEM

This paper applies two methods of mathematical decomposition to carry out an optimal reactive power flow (ORPF) in a coordinated decentralized way in the context of an interconnected multi-area power system. The first method is based on an augmented Lagrangian approach using the auxiliary problem principle (APP). The second method uses a decomposition technique based on the Karush-Kuhn-Tucker (KKT) first-order optimality conditions. The viability of each method to be used in the decomposition of multi-area ORPF is studied and the corresponding mathematical models are presented. The IEEE RTS-96, the IEEE 118-bus test systems and a 9-bus didactic system are used in order to show the operation and effectiveness of the decomposition methods.

Optical spectroscopy of Er3+ and Yb3+ co-doped fluoroindate glasses

Optical absorption, Stokes, and anti-Stokes photoluminescence were performed on Er3+-Yb3+ co-doped fluoroindate glasses. For compounds prepared with a fixed 2 mol % ErF3 concentration and YbF3 contents ranging from 0 to 8 mol %, important upconversion processes were observed as a function of temperature and photon excitation energy. Based on the experimental data, two mechanisms for the upconversion (or anti-Stokes photoluminescence) processes were identified and analyzed in detail. At high Yb contents, the upconversion mechanisms are mostly determined by the population of the 2F5/2 levels of Yb3+ ions (or 4I11/2 levels of Er3+ ions, by energy transfer) regardless of the photon excitation energy and temperature of measurement. Moreover, green and red light emission have similar intensities when a large Yb3+ content is present. © 1998 American Institute of Physics.

Co-feeding of pacu, Piaractus mesopotamicus Holmberg (1887), larvae with Artemia naupili and a microencapsulated diet

Aiming at a precocious substitution of live prey by artificial diet, a 20-day experiment with pacu, Piaractus mesopotamicus, larvae using co-feeding and abrupt weaning strategies was set up. At the end of the experiment, larvae fed Artemia showed the best results (P < 0.05) in weight, total length and biomass, compared with other treatments. Larvae fed exclusively a microencapsulated diet never ingested the diet. Diet ingestion in co-fed and abrupt-weaned larvae was low, but did increase during the experiment; however, Artemia influenced diet ingestion on co-fed larvae. Careful considerations should be given to diet processing and formulation to ensure survival and growth of larvae fed exclusively on prepared diets. © 2005 by The Haworth Press, Inc. All rights reserved.

Direct and simultaneous determination of As, Cu, and Pb in Brazilian sugar cane spirits by graphite furnace AAS using tungsten permanent modifier with co-injection of Pd/Mg(N03)2

A method was developed using the multi-element graphite furnace atomic absorption spectrometry technique for the direct and simultaneous determination of As, Cu, and Pb in Brazilian sugar cane spirit (cachaça) samples. Also employed was the end-capped transversely heated graphite atomizer (THGA) with platforms pre-treated with W permanent modifier and co-injection of Pd/Mg(N03)2. Pyrolysis and atomization temperature curves were established in a cachaça medium (1+1; v/v) containing 0.2% (v/v) HN03 and spiked with 20 μg L-1 As and Pb and 200 μg L-1Cu. The effect of the concentration of major elements usually present in cachaça matrices (Ca, Mg, Na, and K) and ethanol on the absorbance of As, Cu, and Pb was investigated. Analytical working solutions of As, Cu, and Pb were prepared in 10% (v/v) ethanol plus 5.0 mg L-1 Ca, Mg, Na, and K. Acidified to 0.2% (v/v) HNO3, these solutions were suitable to build calibration curves by matrix matching. The proposed method was applied to the simultaneous determination of As, Cu, and Pb in commercial sugar cane spirits. The characteristic mass for the simultaneous determination was 16 pg As, 119 pg Cu, and 28 pg Pb. The pretreated tube lifetime was about 450 firings. The limit of detection (LOD) was 0.6 μg L-1As, 9.2 μg L-1 Cu, and 0.3 μg L-1Pb. The found concentrations varied from 0.81 to 4.28 μg L-1As, 0.28 to 382 mg L-1 Cu and 0.82 to 518 μg L-1 Pb. The recoveries of the spiked samples varied from 94-112% (As), 97-111% (Cu), and 95-101% (Pb). The relative standard deviation (n=12) was 6.9%, 7.4%, and 7.7% for As, Cu, and Pb, respectively, present in a sample at 0.87 μgL-1, 0.81 mgL-1, and 38.9 μgL-1concentrations.

Cytotoxic effects of hard-setting cements applied on the odontoblast cell line MDPC-23

Objective: The present study evaluated the cytotoxic effects of hard setting applied on the odontoblastlike cells MDPC-23. Study design: Eighty round-shaped samples were prepared with the following experimental materials: calcium hydroxide, Vitrebond, RelyX Luting, and RelyX Unicem. The samples were placed in serum-free culture medium and incubated for 24 hours or 7 days at 37°C with 5% CO 2 and 95% air. The odontoblast cells were plated in the wells and incubated for 72 hours. After this period, the complete culture medium was replaced by the extracts obtained from every sample, and the methyltetrazolium assay was carried out to evaluate the cell metabolism. Results: For the 24-hour period, the experimental materials calcium hydroxide, Vitrebond, RelyX Luting, and RelyX Unicem decreased the cell metabolic activity by 91.52%, 81.14%, 78.17%, and 2.64%, respectively. For the 7-day period, calcium hydroxide, Vitrebond, RelyX Luting, and RelyX Unicem decreased the metabolic activity of the MDPC-23 cells by 91.13%, 87.27%, 79.04%, and 10.51%, respectively. Conclusion: RelyX Unicem presented the lowest cytopathic effects to the cultured odontoblast cell line. © 2007 Mosby, Inc. All rights reserved.

A mechatronic system applied to wear particle analysis

This paper describes the development of a mechatronic system for a predictive maintenance grounded on wear particle analysis. The reckoning of wear particles containing in lubricating industrial oils brings the image acquisition system into being. The ISO 4406:1999 standard is a guide to establish the counting and evaluation processes of particles. The system applied to the acquisition and analysis of the data consists of a digital camera, a monocular microscope and an oil filtering system. A computational program was developed with the application of Visual Microsoft C++ in a way to detain the oil sample image from the microscope slide to the computer screen. Quantitative analyses of the wear debris particles bulk are exploited applying a graphical interface that was developed to render the image processing of the sample test. The implemented system has a reachable cost thus it can be applied for schooling goals and for bolstering laboratories of minor industries and medium size companies.

Hallazgos de neuroimagen y desempeño ortográfi co de estudiantes con trastorno por défi cit de atención con hiperactividad según la semiología de los errores

Aim: To characterize, compare and classify the performance of students with attention deficit-hyperactivity disorder (ADHD) according to the semiology of errors and to describe the neuroimaging findings in these students. Methods: We evaluated 36 primary school boys and girls aged between 8 and 11 years old in the 3 rd to 5 th grades. The children were divided in two groups. Group I consisted of 18 students with an interdisciplinary diagnosis of ADHD (60% boys and 40% girls). Group II consisted of 18 children with good academic performance, paired by gender, age and grade with children in group I. The collective and individual versions of the Pro-ortografia spelling tests were applied. Results: Statistically significant differences were found in almost all the tests of the individual and collective versions of the spelling evaluation, with children with ADHD showing a higher average number of errors. Neuroimaging examinations indicated that 81% of the students in GI showed hypoperfusion in the frontal lobe, 7% had hypoperfusion of the thalamus and basal ganglia, 6% showed hypoperfusion in the basal ganglia only and 6% showed hypoperfusion in the left and right frontal lobes. Conclusions: Children with ADHD demonstrated poorer knowledge of the use of spelling rules in Brazilian Portuguese, which could be related to changes in blood flow in the frontal lobe, parietal lobe, thalamus and basal ganglia. These changes could cause a lack of attention, affecting phonological working memory and the planning of writing. © 2011 AELFA.

Genetic (co)variance components for ratio of lamb weight to ewe metabolic weight as an indicator of ewe efficiency

Data from a multibreed commercial flock located at Mid-West of Brazil, supported by Programa de Melhoramento Genético de Caprinos e Ovinos de Corte (GENECOC), were used to estimate genetic parameters of traits related to ewe productivity by Average Information Restricted Maximum Likelihood method applied to an animal model. The analyzed traits were litter weight at birth (LWB) and at weaning (LWW), ewe weight at weaning (EW) and ewe production efficiency, estimated by WEE=LWW/EW 0.75. The heritabilities were 0.26±0.05, 0.32±0.06, 0.37±0.03 and 0.10±0.02 for LWB, LWW, EW and WEE, respectively. Significant effects for direct heterosis were observed for LWW and EW. Recombination losses were important for EW and WEE. Genetic correlations of LWB with LWW, EW and WEE were 0.68, 0.37 and 0.15, respectively; of LWW with EW and WEE were 0.30 and 0.34, respectively; and between EW and WEE was -0.25. Even though it is a low heritability trait, WEE can be indicated as a selection criteria for improving the ewe productivity without increasing the mature weight of animals due to its genetic correlations with LWW and other traits. © 2011 Elsevier B.V.

Influence of current density on crystalline structure and magnetic properties of electrodeposited Co-rich CoNiW alloys

The influence of current density, at the interval 5-100 mA cm-2, on the structural and magnetic properties of electrodeposited (Co 100-xNix)100-yWy alloys (x = 23-33.5 at. % Ni, y = 1.7-7.3 at. % W) was studied from a glycine-containing bath. W-content decreases with the increase of the current density magnitude. X-ray data have shown stabilization of hexagonal close packed, face centered cubic or a mixture of these structures by modulating the applied cathodic current density, for values lower than 50 mA cm-2. Two structural phase transitions were observed: one from hexagonal close packed to face centered cubic structural transition occurring for a current density of 20 mA cm -2, and another one, from cubic crystalline phase to amorphous state, which happens for values higher than 50 mA cm-2. These structural phase transitions seem to be associated with the W-content as well as average crystalline grain sizes that reduce with increasing the current density value. The grain size effect may explain the face centered cubic stabilization in Co-rich CoNiW alloys, which was initially assumed to be basically due to H-adsorption/incorporation. Magnetic properties of Co-rich CoNiW alloys are strongly modified by the current density value; as a result of the changes on the W-content and their structural properties© 2013 Elsevier B.V. All rights reserved.

Fases magnéticas em compostos Er'Co IND. x''Mn IND. 1-x''O IND> 3+ou - δ'

Pós-graduação em Ciência e Tecnologia de Materiais - FC

Aplicação da técnica de RT-PCR in situ na detecção da co-infecção pelo Coronavírus grupo 3 (TCoV) e Astrovírus (TAstV-2) em perus com quadro agudo de enterite

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

Qualidade de vida, ansiedade e depressão em gestantes diabéticas ou co hiperglicemia leve

Pós-graduação em Ginecologia, Obstetrícia e Mastologia - FMB

Green-Markov models - new optimization strategies: a case study for user allocation in co-channel macro/femto networks

ABSTRACT: The femtocell concept aims to combine fixed-line broadband access with mobile telephony using the deployment of low-cost, low-power third and fourth generation base stations in the subscribers' homes. While the self-configuration of femtocells is a plus, it can limit the quality of service (QoS) for the users and reduce the efficiency of the network, based on outdated allocation parameters such as signal power level. To this end, this paper presents a proposal for optimized allocation of users on a co-channel macro-femto network, that enable self-configuration and public access, aiming to maximize the quality of service of applications and using more efficiently the available energy, seeking the concept of Green networking. Thus, when the user needs to connect to make a voice or a data call, the mobile phone has to decide which network to connect, using the information of number of connections, the QoS parameters (packet loss and throughput) and the signal power level of each network. For this purpose, the system is modeled as a Markov Decision Process, which is formulated to obtain an optimal policy that can be applied on the mobile phone. The policy created is flexible, allowing different analyzes, and adaptive to the specific characteristics defined by the telephone company. The results show that compared to traditional QoS approaches, the policy proposed here can improve energy efficiency by up to 10%.