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Search Results: 1 - 10 of 483452 matches for " Wagner de S. Pereira "
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International Recommendations on Calculation of Absorbed Dose in Biota: A Comprehensive Revue  [PDF]
Wagner de S. Pereira, Alphonse Kelecom
Journal of Environmental Protection (JEP) , 2014, DOI: 10.4236/jep.2014.59077
Abstract:

Since the early times, radioprotection has been focused on the human being. Currently this approach has changed, being now also necessary to take care of the protection of the environment from unwanted effects of ionizing radiation. To this end, several institutions (UNSCEAR, ICRP, IAEA, DOE, ACRP) and consortia of institutions (FASSET, ERICA) have established procedures in order to protect the biota of such effects. Developed procedures are based on the calculation of the absorbed dose in biota (ICRP, DOE, IAEA), or on environmental risk assessment―ERA (DOE, ACRP, FASSET, ERICA); but even in this latter approach the parameters used are related to the absorbed doses in biota. The calculation of dose is the standard procedure in human radioprotection, and this points such an approach as the most interesting for providing a convergence between human and nonhuman (= biota) radioprotections. On the other hand, the ERA approach is easier to apply, because this methodology is used in several countries for non-radioactive contamination assessments. Since the world radioprotection system follows a number of institutions (UNSCEAR, ICRP, IAEA and regulatory institutions of member countries) that use dose calculation, this appears to be the way for biota radioprotection. We here review and comment the evolution of the concepts and approaches of the recommendations for radioprotection of non-human biota.

Analysis of Radium Isotopes in Surface Waters nearby a Phosphate Mining with NORM at Santa Quitéria, Brazil  [PDF]
Wagner de S. Pereira, Alphonse Kelecom, Juliana R. de S. Pereira
Journal of Environmental Protection (JEP) , 2014, DOI: 10.4236/jep.2014.53023
Abstract:

The radium isotopes 226Ra and 228Ra were analyzed in surface water at six points in the neighborhood of a mine of phosphate, associated with uranium, in the region of Santa Quitéria, state of Ceará, Brazil. Water samples were collected during twenty months, filtered and the concentrations of activity determined in the soluble and particulate phases. The results were analyzed using the Principal Component Analysis (PCA) for ordination of environmental data, and also by ANOVA, Tukey and Z tests to compare sets of data considering the radionuclides, the two analyzed phases and the six collecting points. The PCA identified four groups that included all collecting points, using aggregation features such as radionuclide and analyzed phase. The first group is composed by the samples of 226Ra in the soluble phase; the second group by samples of 226Ra in the particulate phase; the third one by 228Ra in the soluble phase, and finally, the fourth group by 228Ra in the particulate phase. This last group has two discrepant points (01 and 06). Statistical analysis identified differences between the concentrations of activity of radionuclides (228Ra higher than 226Ra) and in analyzed phases (soluble phase higher than the particulate one) but showed no differences between sampled points.

Release of Uranium by an Ore Treatment Unit at Caldas, MG, Brazil  [PDF]
Wagner de S. Pereira, Alphonse Kelecom, Juliana R. de S. Pereira, Delcy de A. Py Júnior
Journal of Environmental Protection (JEP) , 2013, DOI: 10.4236/jep.2013.46066
Abstract:

This study aims to assess the behavior of the release of Unat (i.e. uranium isotopes in natural relative abundance) from the release of water treated by the Ore Treatment Unit (UTM) in Caldas, state of Minas Gerais, Brazil, during the years 1999 to 2009. During this period, the unit showed no industrial activity, except between 2004 and 2005, when UTM operated 400 tons of monazite in a process to obtain rare earths. Unat was analyzed by spectrophotometry once per week in the effluent waters at sampling point 014. Two fractions were considered for analysis: the soluble one (that passes through a 0.45 μm filter) and the particulate one (retained on a 0.45 μm filter). Statistical analyses were performed: the “Z” test and Pearson’s r2 correlation index. The values for the soluble fraction were consistently lower than those of the particulate fraction and no statistically significant correlation was observed between the soluble and particulate fractions. However, the particulate and the total fractions (the sum of soluble and particulate) strongly correlated.

Activity of natural radionuclides and their contribution to the absorbed dose in the fish cubera snapper (lutjanus cyanopterus, cuvier, 1828) on the coast of Ceara, Brazil
Pereira, Wagner de S.;Kelecom, Alphonse;Py Júnior, Delcy de A.;
Brazilian Journal of Oceanography , 2010, DOI: 10.1590/S1679-87592010000800005
Abstract: a methodology was developed for converting the activity concentration of radionuclides (bq kg-1) into absorbed dose rate (gy y-1), aiming an approach to environmental radioprotection based on the concept of standard dose limit. the model considers only the internal absorbed dose rate. this methodology was applied to the cubera snapper fish (lutjanus cyanopterus, cuvier, 1828) caught off the coast of ceará. the natural radionuclides considered were uranium-238, radium-226, lead-210, thorium-232 and radium-228. the absorbed dose rates were calculated for individual radionuclides and the type of emitted radiation. the average dose rate due to these radionuclides was 5.36 μgy y-1, a value six orders of magnitude smaller than the threshold value of absorbed dose rate used in this study (3.65 103 mgy y-1), and similar to that found in the literature for benthic fish. ra-226 and u-238 contributed 67% and 22% of the absorbed dose rate, followed by th-232 with 10%. ra-228 and pb-210, in turn, accounted for less than 1% of the absorbed dose rate. this distribution is somewhat different from that reported in the literature, where the ra-226 accounts for 86% of the absorbed dose rate.
Synthesis, Characterization and Analysis of Leishmanicide Ability of the Compound [Ru(Cl)3(H2O)2(gly)]  [PDF]
Marcio Adriano S. Chagas, Anderson Dourado Galv?o, Fabricio Tarso de Moraes, A. T. B. N. Ribeiro, Adriano Buzutti de Siqueira, I. C. C. de Assis Salama, Wagner Welber Arrais-Silva, Katia Meirelles Duarte de Sousa, Claudia Cristina de Sousa Pereira, Wagner Batista dos Santos
Open Journal of Inorganic Chemistry (OJIC) , 2017, DOI: 10.4236/ojic.2017.74006
Abstract: Studies of coordinated compounds containing ruthenium (Ru2+ and Ru3+) have shown very effective in vitro results for the treatment of cancer and neglected diseases such as leishmaniasis. In this paper, we present the synthesis of the compound [Ru(Cl)3(H2O)2(gly)], which was characterized by spectroscopic (Ultraviolet-visibleand infrared) and thermal analysis (Thermogravimetry/Derived Thermogravimetry and Thermogravimetry/Differential Thermal Analysis). The analysis of the compound in the Ultraviolet-visibleregion showed a 290 nm band λmax (ε= 1.685 × 103 L·cm-1·mol-1), attributed to the ligand metal charge transfer (LMCT). The spectroscopy (IR) showed major vibrational bands at δa (-COO-) 1664 cm-1, δs (-COO-) 1388 cm-1, δs (\"\") 1571 cm-1 and δs (CCN) 889 cm-1. The thermal analysis by TG/DTG and TG-DTA indicated that the complex has five consecutive stages of decomposition: at 115°C (TG = 12.18%; Calculated = 11.32%) H2O (coordinating water), exothermic peaks at 230°C, 307°C, 440°C and 463°C due to oxidative decomposition of glycine, followed by the formation of RuClO residue at 665°C (TG = 41.11%; Calculated = 40.81%). The thermal characterization suggested the stoichiometry of the complex [RuCl3(H2O)2(gly)]. The antileishmanial capacity of this compound was also evaluated and the results indicated a 31% decrease in the parasitic infection of macrophages and a 1.5 to 3 fold reduction in the number of parasites per cell after treatment with 100 μg/mL of the complex. These results support the possible use of this compound as a therapeutic alternative against medical and veterinary parasites.
Agronomic and economic viability of intercropping onion and lettuce
Mota, Wagner F da;Pereira, Rosimeire D;Santos, Gizeli de S;Vieira, Janiele Cássia B;
Horticultura Brasileira , 2012, DOI: 10.1590/S0102-05362012000200028
Abstract: the study aimed to evaluate the agronomic and economic performance of intercropping onion and lettuce on four plant densities of each species. the experiment was set up in completely randomized blocks, with four replications and treatments arranged in a 4 x 4 factorial. treatments resulted from a combination of four (100, 80, 60, and 40% of recommended plant densities in monoculture) plant densities for both lettuce and onion. intercropping did not affect the agronomic performance of onion or lettuce. higher plant densities (100% for both vegetables) resulted in higher lettuce and onion yields. the best economic results were observed using (a) onion at 80% of plant density combined with lettuce at 40 and 100% and (b) onion at 100% and lettuce at all densities (40 to 100%).
EFFICIENCY OF NEEM OIL ON CITRUS LEPROSIS MITE Brevipalpus phoenicis (GEIJSKES, 1939) CONTROL EFICIêNCIA DO óLEO DE NEEM NO CONTROLE DO áCARO DA LEPROSE DOS CITROS Brevipalpus phoenicis (GEIJSKES, 1939)
Wagner Justiniano,Marcelo Francisco Arantes Pereira,Luís Carlos de Souza Amorim,Cleber Daniel de Goes Maciel
Pesquisa Agropecuária Tropical , 2009, DOI: 10.5216/pat.v39i1.3311
Abstract: In order to determine the efficiency of neem oil on citrus leprosis mite, Brevipalpus phoenicis (Geijskes), control, a laboratory test was conducted in Jaboticabal, S o Paulo State, Brazil, using a completely randomized design, with six treatments and six repetitions. Each plot was formed by one orange fruit (Pêra Rio variety). An area with 4 cm of diameter was delimited in each fruit, using Tanglefoot adhesive. The methodology consisted in submerging each fruit of each treatment in the solution prepared with neem oil (Nim-I-Go ), with 0.5%, 1.0%, 1.5%, and 2.0% v/v; cyhexatin, with 0.025% v/v; and a check submerged in water. After 30 minutes of submersion, eight mites were placed in each fruit and evaluations were made after 24, 48, and 72 hours, determining the mite survival, mortality rate, and mites adhered to the glue. It was found that neem oil, at 1.5% v/v, showed high efficiency to control B. phoenicis on orange fruits, also obtaining the largest number of mites adhered to the glue. It may be concluded that, at this concentration, the product showed repellence action. Under laboratory conditions, the neem oil was effective for citrus leprosis mite control. KEY-WORDS: Citrus leprosis mite; Azadirachta indica.
Calorímetro diferencial para estudo do padr?o de aquecimento gerado por feixes ultrass?nicos terapêuticos
Omena, Thaís Pionório;Costa, Rejane Medeiros;Pereira, Wagner Coelho de Albuquerque;Krüger, Marco Ant?nio von;
Revista Brasileira de Engenharia Biomédica , 2012, DOI: 10.4322/rbeb.2012.035
Abstract: the present work describes the project and construction of a differential calorimeter designed to evaluate the heating generated by ultrasound beam in therapeutic levels. the calorimeter consists of two identical aluminum cylindrical chambers (for measurement and reference) filled with biological tissue mimicking material (phantom). each chamber is fitted with six thermocouples type e (0.24 mm diameter) disposed along the wave propagation central axis, between the depths of 10-60 mm, distant 10 mm from each other. the power curve and the value of the effective radiation area (era) of the two transducers were estimated. from these data, the effective intensity was determined. the calorimeter was tested by using an ultrasound equipment of physiotherapy, operating at the frequencies 1 and 3 mhz, continuous mode, nominal intensities 0.5, 1.0, 1.5 and 2.0 w.cm-2 and irradiation time 180 seconds. a sequence of eight protocols of measurement was repeated 10 times. at both frequencies, there was a decline of heating along the depth and the phantom region that heated the most corresponded to 10 mm of depth, in all intensities employed. the greatest increase in temperature occurred after application of 2.0 w.cm-2, with averages of 6.7 ± 1.0 oc and 12.6 ± 1.2 oc, at 1 mhz and 3 mhz, respectively. the proposed calorimeter may be useful for identifying possible local temperature maxima (hot spots) that appear along the central axis beam.
Sistema imunitário - parte II: fundamentos da resposta imunológica mediada por linfócitos T e B
Mesquita Júnior, Danilo;Araújo, Júlio Ant?nio Pereira;Catelan, Tania Tieko Takao;Souza, Alexandre Wagner Silva de;Cruvinel, Wilson de Melo;Andrade, Luís Eduardo Coelho;Silva, Neusa Pereira da;
Revista Brasileira de Reumatologia , 2010, DOI: 10.1590/S0482-50042010000500008
Abstract: the immune system consists of an intricate network of organs, cells, and molecules responsible for maintaining the body's homeostasis and responding to aggression in general. innate immunity operates in conjunction with adaptive immunity and is characterized by rapid response to aggression, regardless of previous stimulus, being the organism first line of defense. its mechanisms include physical, chemical and biological barriers, cellular components, as well as soluble molecules. the organism first line of defense against tissue damage involves several steps closely integrated and constituted by different components of this system. the aim of this review is to restore the foundations of this response, which has high complexity and consists of several components that converge to articulate the development of adaptive immune response. we selected some of the following steps to review: perception and molecular recognition of aggressive agents; activation of intracellular pathways, which result in vascular and tissue changes; production of a myriad of mediators with local and systemic effects on cell activation and proliferation, synthesis of new products involved in the chemoattraction and migration of cells specialized in destruction and removal of offending agent; and finally, tissue recovery with restoration of functional tissue or organ.
Sistema imunitário: Parte I. Fundamentos da imunidade inata com ênfase nos mecanismos moleculares e celulares da resposta inflamatória
Cruvinel, Wilson de Melo;Mesquita Júnior, Danilo;Araújo, Júlio Ant?nio Pereira;Catelan, Tania Tieko Takao;Souza, Alexandre Wagner Silva de;Silva, Neusa Pereira da;Andrade, Luís Eduardo Coelho;
Revista Brasileira de Reumatologia , 2010, DOI: 10.1590/S0482-50042010000400008
Abstract: the immune system consists of an intricate network of organs, cells, and molecules responsible for maintaining the body's homeostasis and responding to aggression in general. innate immunity operates in conjunction with adaptive immunity and is characterized by rapid response to aggression, regardless of previous stimulus, being the organism first line of defense. its mechanisms include physical, chemical and biological barriers, cellular components, as well as soluble molecules. the organism first line of defense against tissue damage involves several steps closely integrated and constituted by different components of this system. the aim of this review is to restore the foundations of this response, which has high complexity and consists of several components that converge to articulate the development of adaptive immune response. we selected some of the following steps to review: perception and molecular recognition of aggressive agents; activation of intracellular pathways, which result in vascular and tissue changes; production of a myriad of mediators with local and systemic effects on cell activation and proliferation, synthesis of new products involved in the chemoattraction and migration of cells specialized in destruction and removal of offending agent; and finally, tissue recovery with restoration of functional tissue or organ.
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