28 resultados para anomalous Eu3 5D0->F-7(0) transition

em Universidade Federal do Rio Grande do Norte(UFRN)


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The reproductive ecology of fish plays a key role both for rational exploitation methods and for protective measures of natural stocks. The purpose of this study was to analyze the reproductive aspects of the damsel-fish, Stegastes fuscus, during October 2004 to September 2005, in the coastal rocky reefs of Bzios Beach, Nsia Floresta, RN. Fish were captured using hooks and hand nets, during low tide. Reproduction was determined using sexual ratio, mean length of first maturation (L50), absolute fecundity and macroscopic characteristics of gonads. The following parameters were related to gonadosomatic index (GSI): condition factor (CF), hepatosomatic index (HSI), rain fall and temperature. In relation to sex distribution, it was observed that 78% were females and 22% were males. The L50 was 6.2 cm for females and 7.0 for males. Average fecundity was 6832 oocytes. Results showed that S. fuscus had better body condition in the months prior to spawning, particularly during initial and intermediate stages of maturation. Five stages of gonadal maturation were identified through macroscopic analysis: immature, in maturation, mature, spent and resting. The HSI was inversely related to the GSI. This was possibly due to the reproductive cycle of this species which was associated to the dry period of this region. During this period, low rain fall and high temperatures provide an propitious reproductive condition for the study species

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The objective of the current study was to evaluate the zootechnical performance (survival and growth) of Litopenaeus vannamei post-Iarvae fed an artificial shrimp diet supplemented with Artemia flakes or freeze-dried Artemia embryos. For that purpose, 20 culturing units were individually stocked with 50 shrimp post-Iarvae (average dry weight of 0,3 0,03 mg) at a stocking density of 20 post-larvae per liter, and fed the experimental diets to satiation during 20 days. The experimental design consisted of four diets (T1, T2, T3 and T4) with five repetitions each. For treatments T1, T2 and T3, dietary supplements of 5mg of Artemia flakes (T1), freeze-dried Artemia embryos (T2), and of the commercial shrimp diet (T3) were offered 2 hours after the shrimp were initially fed the commercial shrimp diet. For treatment T4 (control), no additive was offered 2 hours after the initial feeding. Shrimp survival, absolut (GPA) and relative increase in weight (GPR), and specific growth rate (TCR) were used as evaluation criteria. After the experimental period, no significant statistical differences (p>0,05) in survival were observed. Regarding growth, the dietary treatment which used freeze-dried Artemia embryos as an additive (T2) presented the best results for GPA (6,7 0,7 mg). There were no statistical differences within treatments T1, T3 and T4 (p>0,05). AIso, post-larvae fed freeze-dried embryos (T2) showed a relative increase in weight (2241,4%) which differed significantly (p<0,05) from T4(1911,7%) but not from T1 (1801,6%) or T3 (1946,7%). In conclusion, the results of the current study indicate that an artificial shrimp diet supplemented with freeze-dried Artemia embryos fulfils the nutritional requirements of post-larvae L. vannamei and promotes a better growth than diets not supplemented with Artemia flakes

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Since the first description of sulfated polysaccharides from seaweeds, the biological activities of these compounds have been evaluated under different aspects and experimental procedures. Among the broad biological activities presented by seaweed polysaccharides, anticoagulant action appears as a promising function. In this present study we have obtained sulfated polysaccharides from the green seaweed Codium isthmocladium by proteolytic digestion, followed by separation into five fractions (0.3, 0.5, 0.7, 0.9 and 1.2) by sequential acetone precipitation. The chemical analyses have demonstrated that all fractions are composed mainly by sulfated polysaccharides. The anticoagulant activity of these fractions was determined by activated partial thromboplastin time (aPTT) and prothrombin time test (PT) using citrate normal human plasma. None fraction has shown anticoagulant activity by PT test. Furthermore, all of them have shown anticoagulant activity by aPTT test. These results indicated that the molecular targets of these sulfated polysaccharides are mainly in the intrinsic via of the coagulation cascade. Agarose gel electrophoresis in 1,3-diaminopropane acetate buffer, pH 9.0, stained with 0.1% toluidine blue showed the presence of two or three bands in several fractions while the fraction 0.9 showed a single spot. By anion exchange chromatography, the acid polysaccharides from the 0.9 acetone fraction were separated into two new fractions eluted respectively with 2.0 and 3.0 M NaCl. These compounds showed a molecular weight of 6.4 and 7.4 kDa respectively. Chemical analyses and infrared spectroscopy showed that Gal 1 and Gal 2 are sulfated homogalactans and differ one from the other in degree and localization of sulfate groups. aPPT test demonstrated that fractions 2,0 and 3,0M (Gal1 and Gal 2, respectively) have anticoagulant activity. This is the first time that anticoagulant sulfated homogalatans have been isolated from green algae. To prolong the coagulation time to double the baseline value in the aPTT, the required amount of sulfated galactan 1 (6,3mg) was similar to low molecular heparin Clexane, whereas only 0,7mg of sulfated galactan 2 was needed to obtain the same effect. Sulfated galactan 2 in high doses (250mg) induces platelet aggregation. These results suggest that these galactans from C. isthmocladum have a potential application as an anticoagulant drug

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Fungal polysaccharides have received a great deal of attention due to itsbecause of their potential use in a wide rangegreat variety fromof industries. Some studies have demonstrated that polysaccharides extracted offrom basidiomycetes they have presented significant properties as anti-inflammatory, antimicrobial, antioxidant and anti-tumoral properties. In spite of thisDespite these potential properties, these mushrooms have not been insufficiently investigated, and the great number of antibiotics number produced forby these organisms suggests that they canmay be a new source of bioactives composites source. In tThe present work, reports onlated the chemical composition, potential antioxidant, antiinflammatory and citotoxycity of extracted polymers extracted offrom the fruits bodies of the fungiius Geastrum saccatum and Polyporus dermoporus, native mushrooms of the Atlantic forest inof the state of the Rio Grande do Norte, Brazil. The Cchemical analyses had revealed ademonstrated text of total sugar rates of 65% and 49%, and proteins of 7.0% for in extracts of G. saccatum and P. dermoporus extracts, respectively. The analyses ofNMR spectroscopy of RMN had demonstrated that these extracts are composites forof a complex involving &#946;- glucans and- proteins complex. The inhibition of the formation of superoxide radicals formation was of 88.4% in G. saccatum and 83.3% in P. dermoporus, and 75 and 100% for inhibition of hydroxyls radicals inhibition. TopicalThe topic application of extracts the 10, 30 and 50 mg/kg extract in BALBc mice with cutaneous inflammation induced byfor croton oil demonstrated to inhibitedion of ear edema of ear and cells polimorfonuclears cells atin the inflamed siteplace, being this reply more effective in lower concentrations being more effective. The evaluation of the glucans of G. saccatum and P. dermoporus glucans under induced pleurisy for carrageenan-induced pleurisya of showed the antiinflammatory action of these composites., being analyzed tThe frame number in the pleural exudates and thedosage of nitric oxide dosage was also analyzed. The cytotoxic action of these polymers was analyzed throughthrough the mitochondrial function (MTT). The incubation of the glucans with mononuclear cells of the peripheral blood demonstrated that the extracted glucans extracted fromof G. saccatum havepossess a moderate cytotoxic action. These results suggest that these mushrooms possess polymers formed byfor a complex glucana-protein complex, with antiinflammatory and antioxidant actions

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Portland-polymers composites are promising candidates to be used as cementing material in Northeastern oil wells of Brazil containing heavy oils submitted to steam injection. In this way, it is necessary to evaluate its degradation in the commonly acidizind agents. In addition, to identify how aggressive are the different hostile environments it is an important contribution on the decision of the acidic systems to be used in. It was investigated the performance of the Portland-polymer composites using powdered polyurethane, aqueous polyurethane, rubber tire residues and a biopolymer, those were reinforced with polished carbon steel SAE 1045 to make the electrochemical measurements. HCl 15,0 %, HCl 6,0 % + HF 1,5 % (soft mud acid), HCl 12,0 % + HF 3,0 % (regular mud acid) and HAc 10 % + HF 1,5 % were used as degrading environment and electrolytes. The more aggressive acid solution to the plain Portland hardened cement paste was the regular mud acid, that showed loss of weight around 23.0 %, followed by the soft mud acid, the showed 11.0 %, 15.0 % HCl with 7,0 % and, at last the 10.0 % HAc plus HF 1.5 % with just 1.0 %. The powdered polyurethane-composite and the aqueous polyurethane one showed larger durability, with reduction around 87.0 % on the loss of weight in regular mud acid. The acid attack is superficial and it occurs as an action layer, where the degraded layer is responsible for the decrease on the kinetic of the degrading process. This behavior can be seen mainly on the Portland- aqueous polyurethane composite, because the degraded layer is impregnated with chemically modified polymer. The fact of the acid attack does not have influence on the compressive strength or fratography of the samples, in a general way, confirms that theory. The mechanism of the efficiency of the Portland-polymers composites subjected to acid attack is due to decreased porosity and permeability related with the plain Portland paste, minor quantity of Ca+2, element preferentially leached to the acidic solution, wave effect and to substitute part of the degrading bulk for the polymeric one. The electrolyte HAc 10 % + HF 1,5 % was the least aggressive one to the external corrosion of the casing, showing open circuit potentials around +250 mV compared to -130 mV to the simulated pore solution to the first 24 hours immersion. This behavior has been performed for two months at least. Similar corrosion rates were showed between both of the electrolytes, around 0.01 &#956;A.cm-2. Total impedance values, insipient arcs and big polarization resistance capacitive arcs on the Nyquist plots, indicating passivity process, confirm its efficiency. In this way, Portlandpolymers composites are possible solutions to be succeed applied to oilwell cementing concomitant submitted to steam injection and acidizing operation and the HAc 10,0 % + HF 1,5 % is the less aggressive solution to the external corrosion of the casing

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In the ceramics industry are becoming more predominantly inorganic nature pigments. Studies in this area allow you to develop pigments with more advanced properties and qualities to be used in the industrial context. Studies on synthesis and characterization of cobalt aluminate has been widely researched, cobalt aluminate behavior at different temperatures of calcinations, highlighting especially the temperatures of 700, 800 and 900 C that served as a basis in the development of this study, using the method of polymerization of complex (CPM), economic, and this method applied in ceramic pigment synthesis. The procedure was developed from a fractional factorial design 2 (5-2) in order to optimize the process of realization of the cobalt aluminate (CoAl2O4), having as response surfaces the batch analysis data of Uv-vis spectroscopy conducted from the statistic software 7.0, for this were chosen five factors as input variables: citric acid (stoichiometric manner), puff or pyrolysis time (h), temperature ( C), and calcinations ( C/min), at levels determined for this study. By applying statistics in the process of obtaining the CoAl2O4 is possible the study of these factors and which may have greater influence in getting the synthesis. The pigments characterized TG/DSC analyses, and x-ray diffraction (XRD) and scanning electron microscope (SEM/EDS) in order to establish the structural and morphological aspects of pigment CoAl2O4, among the factors studied it were found to statically with increasing calcinations temperature 700< 800 <900 C, the bands of Uv-vis decrease with increasing intensity of absorbance and that with increasing time of puff or pyrolysis (h) there is an increase in bands of Uv-vis proportionally, the generated model set for the conditions proposed in this study because the coefficient of determination can explain about 99.9% of the variance (R), response surfaces generated were satisfactory, so it s possible applicability in the ceramics industry of pigments

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Synthetic inorganic pigments are the most widely used in ceramic applications because they have excellent chemical and thermal stability and also, in general, a lower toxicity to man and to the environment. In the present work, the ceramic black pigment CoFe2O4 was synthesized by the polymerization Complex method (MPC) in order to form a material with good chemical homogeneity. Aiming to optimize the process of getting the pigment through the MPC was used a fractional factorial design 2(5-2), with resolution III. The factors studied in mathematical models were: citric acid concentration, the pyrolysis time, temperature, time and rate of calcination. The response surfaces using the software statistica 7.0. The powders were characterized by thermal analysis (TG/DSC), x-ray diffraction (XRD), scanning electron microscopy (SEM) and spectroscopy in the UV-visible. Based on the results, there was the formation of phase cobalt ferrite (CoFe2O4) with spinel structure. The color of the pigments obtained showed dark shades, from black to gray. The model chosen was appropriate since proved to be adjusted and predictive. Planning also showed that all factors were significant, with a confidence level of 95%

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Coordenao de Aperfeioamento de Pessoal de Nvel Superior

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The dams are limnic ecosystems of great importance for its multiple uses, among them, water supply for the public and to culture of artisanal fish are most relevant. The aim of the present study is to evaluate the physical-chemical characteristics and the phytoplankton community in two chosen sites (Point 1 littoral zone of point source; Point 2 pelagic zone of non-point source) of the Minister Joo Alves dam, which is also known as Boqueiro de Parelhas/RN. This represents the spatial distribution of the phytoplankton species in order to understand any possible alterations of the water quality and the phytoplankton composition in relation to the water quality originating from the impact of the tilapia, Oreochromis niloticus, culture. The study period also encompasses temporal variations exhibited in two seasons of an annual cycle, one during the dry season (Oct, Nov and Dec of 2008 and Jan of 2009), and the other rainy season (Mar, Apr, May and June of 2008) to extend the observation. The physicalchemical parameters, such as pH, temperature, electrical conductivity, concentration of dissolved oxygen were measured in situ and the values of the inorganic nutrients (nitrate, ammonium and orto-phosfato) and chlorophyll in the laboratory. The quali-quantitative analyses of the phytoplankton had been carried through sedimentation technique and the enumeration of the random of 400 cells, colonies and filaments counted using Sedgwick-Rafter counting chamber. The results of pH varied widely from the acidic to alkaline range with the minimum of 5.8 ( 0.8) and the maximum of 9.2 ( 0.7-0.8), at point 1 and 2. The dissolved oxygen content was higher in the rainy period than that in the dry period. The maximum electrical conductivity was of 1409 &#956;Scm-1 in point 1 and 431 minim of &#956;Scm-1, in point 2. There was a considerable alteration in the levels of inorganic nutrients such as nitrate-nitrogen, ammoniacal nitrogen and orthophosphate during the two cycles of study period. Phytoplankton assemblages presented a picture of alternate dominance among species Cyanobacteria, Bacillariophyceae and Chlorophyceae. The trophic state index diagnosed to the category of mesotrophic, which is based on the values of chlorophyll, total phosphorus and Secchi-disc measurements. The wind driven turbulence of the water column and the fresh inflow of water (flushing and dilution) during rainy season acted as constraint and did-not allow an exaggerated growth of the species of cyanobacteria. On the basis of the present we conclude that the culture of tilapias in cage-culture fails to produce pollution load that could compromise the quality of the water of the dam, probably be due to small dimension of the culture in relation to the size, volume of the water and the reservoir capacity support its own environment

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analisar o efeito do treinamento aerbio periodizado sobre a aptido cardiorrespiratria e respostas afetivas em mulheres com sndrome dos ovrios policsticos (SOP) e II) investigar se o exerccio aerbio realizado na zona de prazer para essa populao atende a recomendao do American College of Sports Medicine (ACSM) no que se refere intensidade para melhoria da sade. Metodologia: foram includas mulheres na faixa etria entre 18 e 34 anos, com diagnstico de SOP de acordo com o Consenso de Rotterdam. Para o subestudo I, oito pacientes sedentrias participaram de 16 semanas de treinamento aerbio com incrementos mensais de intensidade: fase 1 = 60-70% da frequncia cardaca mxima (FCmax); fase 2 = 70-75% da FCmax; fase 3 = 75-80% da FCmax; fase 4 = 80-85% da FCmax. A interveno foi realizada trs vezes por semana, 40 minutos por sesso. Em todas as sesses foram registradas as respostas afetivas (Feeling Scale -5/+5) e a percepo subjetiva do esforo (escala de Borg CR 6-20). Antes e aps a interveno, as voluntrias realizaram teste ergoespiromtrico. Para o subestudo II, 11 pacientes realizaram duas sesses de exerccio aerbio na zona de prazer, sendo registrados parmetros relativos demanda fsica atravs de receptor de GPS (Global Positioning System) de pulso com cardiofrequencmetro acoplado. As pacientes foram instrudas a realizar 40 minutos de exerccio guiadas pelas ncoras verbais bom e muito bom (+3 e +5 na Feeling Scale). Resultados: no subestudo I, aps 16 semanas de treinamento, houve aumento da aptido cardiorrespiratria mxima (17,3%) e submxima (21,5%). As respostas afetivas variaram entre bom (+3,1 0,8) e razoavelmente bom xi (1,0 0,9) e a percepo subjetiva do esforo entre muito leve a leve (10,2 0,7) e um pouco difcil (12,7 0,6) durante a interveno. No subestudo II, as pacientes exercitaram-se a ~72,5 6% da FC mxima, ~78,5 6% da FC no limiar anaerbio e passaram > 95% do tempo em intensidade moderada (~82%) e vigorosa (~16%) durante as sesses experimentais. Em mdia, as voluntrias reportaram as sesses como fcil (percepo subjetiva do esforo da sesso ~2,2 0,7). Concluses: o programa de treinamento aerbio periodizado aumentou a aptido cardiorrespiratria das pacientes analisadas e foi percebido como uma interveno prazerosa. Adicionalmente, exerccio aerbio realizado de forma prazerosa atende a recomendao do ACSM no que se refere intensidade para melhoria da sade

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As disfunes temporomandibulares (DTM) representam a maior causa de dor no dentria da regio orofacial. Dada sua alta prevalncia na populao em geral e a existncia de inmeros instrumentos diagnsticos no padronizados, buscou-se elaborar e validar um questionrio simples, de acessibilidade ampla e aplicao prtica, com vistas a contribuir para o diagnstico e o estudo epidemiolgico das mesmas. A estratgia utilizada na montagem do instrumento foi estabelecida com base na avaliao criteriosa de questionrios j existentes na literatura, validao de expertos na rea de DTM, validao fatorial, de face (na primeira fase do estudo) e, frente ao padro ouro (RDC/TMD), na segunda fase do estudo. Na primeira fase, participaram 160 indivduos. A consistncia interna resultou num Coeficiente Alfa de Cronbach de 0,752 para o questionrio com sete itens; enquanto que para o questionrio com cinco itens, este resultado foi de 0,694, no sendo o mesmo, considerado baixo por avaliar apenas cinco questes e ainda, em razo do tema central da pesquisa ser bastante subjetivo. A anlise fatorial confirmatria apontou para uma varincia total dos fatores extrados do questionrio com sete itens, de 58,2 % e do questionrio com cinco itens de 70,04%. Portanto, o questionrio com cinco questes, apresentou resultados estatsticos superiores ao de sete questes. Na validao frente ao padro ouro (RDC/TMD), foram avaliados 99 indivduos tendo sido testados os dois questionrios, com sete e com cinco questes. Na estrutura com sete questes, ao se categorizar as mesmas por totais de pontos obtidos, em quatro condies, obteve-se o melhor resultado quando se considerou com DTM a faixa entre 10 e 21 pontos, sendo 85,1% positivos tambm no RDC/TMD, com acurcia de 90,1% e Kappa 0,817. Nesta condio, a sensibilidade encontrada foi de 95% (IC 95%, 91 a 99), especificidade de 87% (IC 95%, 81 a 93), VPP 85%, VPN 96%, LR+ 7,3 e LR- 17,4. Quando os dados foram avaliados para o questionrio com cinco questes (QST/DTM), pode-se observar que o melhor ponto de corte foi quando se considerou como portadores de DTM, os indivduos na faixa entre 7 e 15 pontos, com acurcia de 85,8% e Kappa 0,817. Nesta condio, a sensibilidade foi 88% (IC 95%, 81,6 a 94,4), especificidade 84% (IC 95%, 76,8 a 91,2), VPP 80%, VPN 90,5%, LR+ 5,5 e LR- 7,0. A simplicidade do presente questionrio (QST/DTM) com apenas cinco questes, possibilita seu uso como elemento de triagem inicial na rea da dor orofacial em disfuno temporomandibular, com boa compreensibilidade, confiabilidade, reprodutibilidade e possibilidade de aplicao em pesquisas epidemiolgicas. Concluiu-se que o questionrio aqui validado, permite sua aplicao de forma simples tanto por profissionais e pesquisadores da Odontologia como de outras reas da sade

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Kalanchoe brasiliensis Cambess (Crassulaceae), commonly known as saio , coirama branca , folha grossa , is originally from Brazil and commonly found in So Paulo to Bahia, mainly in the coastal zone. Regarding of biological activities, most preclinical studies were found in the literature, mainly about the anti-inflammatory activity of extracts obtained from leaves and / or aerial parts of K. brasiliensis. As regards the chemical constitution, it has been reported mainly the presence of flavonoids in the leaves of the species, but until this moment did not knows which are the active compounds. Although it is a species widely used in traditional medicine in Brazil, there is no monograph about the quality parameters of the plant drug. In this context, this study aims to characterize and quantify the chemical markers of hydroethanolic extract (HE) from the leaves of K. brasiliensis, which can be used in quality control of plant drug and derivatives obtained from this species. The methodology was divided into two parts: i. Phytochemical study: to fractionate, isolate and characterizate of the chemical (s) marker (s) of the HE from the leaves of K. brasiliensis; ii. To Developed validate of analytical method by High Performance Liquid Chromatography (HPLC)-diode array detector (DAD) to quantify the chemical (s) marker (s) of the EH. i. The EH 50% was prepared by turbo extraction method. It was then submitted to liquid-liquid partition, obtaining dichloromethane, n-butanol and ethyl acetate (AcOEt) fractions. The AcOEt fraction was selected to continue the fractionation process, because it has a chemical profile rich in flavonoids. The acOEt fraction was submitted to column chromatography using different systems for obtaining the compound Kb1. To identify this compound, it was submitted to UV analysis ii. For quantitative analysis, the EH was analyzed by HPLC, using different methods. After selecting the most appropriate method, which showed satisfactory resolution and symmetrical peaks, it was validated according to parameters in the RE 899/2003. As result, it was obtained from the AcOEt fraction the compound Kb1 (2.7 mg). Until this moment, the basic nucleus was characterized by UV analysis using shift reagents. The partial chemical structure of the compound Kb1 was identified as a flavonol, containing hydroxyls in 3 , 4 position (ring A), 5 and 7 free (ring B) and a replacement of the C3 hydroxyl by a sugar. As the analysis were performed in the HPLC coupled to a DAD, we observed that the UV spectrum of the major peaks of EH from K. brasiliensis shown similar UV spectrum. According to the literature, it has been reported the presence of patuletin glycosydes derivatives in the leaves of this species. Therefore, it is suggested that the compound Kb1 is glycosylated patuletin derivative. Probably the sugar (s) unit(s) are linked in the C3 in the C ring. . Regarding the development of HPLC analytical method, the system used consists of phase A: water: formic acid (99,7:0,3, v / v) and phase B: methanol: formic acid (99,7:0,3, v / v), elution gradient of 40% B - 58% B in 50 minutes, ccolumn (Hichrom ) C18 (250x4, 0 mm, 5 m), flow rate 0.8 mL / min, UV detection at 370 nm, temperature 25 C. In the analysis performed with the co-injection of thecompound Kb1 + HE of K. brasiliensis was observed that it is one of the major compounds with a retention time of 12.47 minutes and had a content of 15.3% in EH of leaves from K. brasiliensis. The method proved to be linear, precise, accurate and reproducible. According to these results, it was observed that compound Kb1 can be used as a chemical marker of EH from leaves of K. brasiliensis, to assist in quality control of drug plant and its derivatives

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Gene therapy is based on the transfer of exogenous genetic material into cells or tissues in order to correct, supplement or silencing a particular gene. To achieve this goal, efficient vehicles, viral or non-viral, should be developed. The aim of this work was to produce and evaluate a nanoemulsion system as a possible carrier for no-viral gene therapy able to load a plasmid model (pIRES2-EGFP). The nanoemulsion was produced by the sonication method, after been choose in a pseudo-ternary phase diagram build with 5 % of Captex 355, 1.2 % of Tween 80, 0.8 % of Span 80, 0.16% of stearylamine and water (to 100 %). Measurements of droplet size, polydispersity index (PI), zeta potential, pH and conductivity, were performed to characterize the system. Results showed droplets smaller than 200 nm (PI < 0.2) and zeta potential > 30 mV. The formulation pH was near to 7.0 and conductivity was that expected to oil in water systems (70 to 90 &#956;S/s) A scale up study, the stability of the system and the best sterilization method were also evaluated. We found that the system may be scaled up considering the time of sonication according to the volume produced, filtration was the best sterilization process and nanoemulsions were stable by 180 days at 4 C. Once developed, the complexation efficiency of the plasmid (pDNA) by the system was tested by agarose gel electrophoresis retardation assay.. The complexation efficiency increases when stearylamine was incorporated into aqueous phase (from 46 to 115 ng/&#956;L); regarding a contact period (nanoemulsion / pDNA) of at least 2 hours in an ice bath, for complete lipoplex formation. The nanoemulsion showed low toxicity in MRC-5 cells at the usual transfection concentration, 81.49 % of survival was found. So, it can be concluded that a nanoemulsion in which a plasmid model was loaded was achieved. However, further studies concerning transfectation efficiency should be performed to confirm the system as non-viral gene carrier

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Knowledge and innovation were seen as major forces, both for survival, as the acquisition of competitive advantages in the Brazilian economy, as well as adding value to the product as a market differentiator. The Triple Helix model is directed toward the knowledge-based economy. Over the past six years, the Federal Government through the Financier of Studies and Projects ( FINEP ) invested in technological innovation projects, economic subsidies, about U.S. $ 1 billion supporting more than 800 projects with these resources. According to the MCTI , the Northeast, over the years 2000 to 2010 increased spending on Science and Technology (considering the activities of research and development more scientific and related activities) of the State Government in relation to its total revenue In 2000, 0.51% of total revenues were invested in Science & Technology, while in 2010 this figure increased to 1.31%. Among the nine Northeast states, Paraba is highlighted. In 2000, 0.33% of its total revenues were directed to innovation, reaching 2.04% in 2010, the largest increase in the region while the RN invested 0.24% in 2000 and in 2010 reached the level of 1.42 %. According to IBGE, in the period 2000-2011, the micro and small enterprises surpassed the barrier of 6 million establishments. In 2000, there were 4.2 million establishments while in 2011 were 6.3 million active establishments. Therefore, throughout the period, there was a creation of approximately 2.1 million new establishments. Between 2000 and 2011, micro and small businesses have created 7.0 million formal jobs, 8.6 million jobs in 2000 to 15.6 million in 2011. This scenario shows the importance of this study in relation to the investment of governments in RD & I in micro and small enterprises. This study aims to analyze the interaction Universities - Business - Government in the development of innovation in micro and small companies in Rio Grande do Norte participants of the edicts of Inova FAPERN. We chose to adopt as a research method case study concerning the procedure of the research, exploratory, descriptive, and on documents with engineers and researchers of innovation projects approved by PAPPE Subsidy (Inova -RN I, II and III). Data collection was done through the report made by FAPERN entitled: " Evaluation of companies financed and supported by the Grant Program for Technological Innovation for Micro and Small Enterprises RN - INOVA -RN " (2010) and a questionnaire with 40 closed questions and 1 opened to 30 affirmative composed based on a 5-point Likert scale. The analysis of data was qualitative and quantitative. The study provided to identify the importance and barriers arising from the relation between Government Enterprise (micro and small) and University as essential to the economic development of the region. It was also identified that, in the innovation projects, 70% of the goods or services originating from research were to market these, 50% resulted in a patent for the company and 80% publications of scientific articles

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Fuel is a material used to produce heat or power by burning, and lubricity is the capacity for reducing friction. The aim of this work is evaluate the lubricity of eight fossil and renewable fuels used in Diesel engines, by means of a HFRR tester, following the ASTM D 6079-04 Standard. In this conception, a sphere of AISI 52100 steel (diameter of 6,00&#61617;0,05 mm, Ra 0,05&#61617;0,005 &#956;m, E = 210 GPa, HRC 62&#61617;4, HV0,2 631&#61617;47) is submitted to a reciprocating motion under a normal load of 2 N and 50 Hz frequency to promote a wear track length of 1.1&#61617;0.1mm in a plan disc of AISI 52100 steel (HV0,05 184&#61617;10, Ra 0,02&#61617;0,005 &#956;m). The testing extent time was 75 minutes, 225,000 cycles. Each one test was repeated six times to furnish the results, by means of intrinsic signatures from the signals of the lubricant film percentage, friction coefficient, contact heating, Sound Pressure Level, SPL [dB]. These signal signatures were obtained by two thermocouples and a portable decibelmeter coupled to a data acquisition system and to the HFRR system. The wettability of droplet of the diesel fuel in thermal equilibrium on a horizontal surface of a virgin plan disc of 52100 steel, Ra 0,02 &#61617; 0,005 &#956;m, were measured by its contact angle of 7,0 &#61617; 3,5o, while the results obtained for the biodiesel B5, B20 and B100 blends originated by the ethylic transesterification of soybean oil were, respectively, 7,5 &#61617; 3,5o, 13,5 &#61617; 3,5o e 19,0 &#61617; 1,0o; for the distilled water, 78,0 &#61617; 6,0o; the biodiesel B5, B20 and B100 blends originated by the ethylic transesterification of sunflower oil were, respectively, 7,0 &#61617; 4,0o, 8,5 &#61617; 4,5o e 19,5 &#61617; 2,5o. Different thickness of lubricant film were formed and measured by their percentage by means of the contact resistance technique, suggesting several regimes, since the boundary until the hydrodynamic lubrication. All oils analyzed in this study promoted the ball wear scars with diameters smaller than 400 &#956;m. The lowest values were observed in the scar balls lubricated by mixtures B100, B20 and B5 of sunflower and B20 and B5 of soybean oils (WSD < 215 &#956;m)