15 resultados para Vaso-occlusion

em Universidade Federal do Rio Grande do Norte(UFRN)


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This work intends to analyze the behavior of the gas flow of plunger lift wells producing to well testing separators in offshore production platforms to aim a technical procedure to estimate the gas flow during the slug production period. The motivation for this work appeared from the expectation of some wells equipped with plunger lift method by PETROBRAS in Ubarana sea field located at Rio Grande do Norte State coast where the produced fluids measurement is made in well testing separators at the platform. The oil artificial lift method called plunger lift is used when the available energy of the reservoir is not high enough to overcome all the necessary load losses to lift the oil from the bottom of the well to the surface continuously. This method consists, basically, in one free piston acting as a mechanical interface between the formation gas and the produced liquids, greatly increasing the well s lifting efficiency. A pneumatic control valve is mounted at the flow line to control the cycles. When this valve opens, the plunger starts to move from the bottom to the surface of the well lifting all the oil and gas that are above it until to reach the well test separator where the fluids are measured. The well test separator is used to measure all the volumes produced by the well during a certain period of time called production test. In most cases, the separators are designed to measure stabilized flow, in other words, reasonably constant flow by the use of level and pressure electronic controllers (PLC) and by assumption of a steady pressure inside the separator. With plunger lift wells the liquid and gas flow at the surface are cyclical and unstable what causes the appearance of slugs inside the separator, mainly in the gas phase, because introduce significant errors in the measurement system (e.g.: overrange error). The flow gas analysis proposed in this work is based on two mathematical models used together: i) a plunger lift well model proposed by Baruzzi [1] with later modifications made by Bolonhini [2] to built a plunger lift simulator; ii) a two-phase separator model (gas + liquid) based from a three-phase separator model (gas + oil + water) proposed by Nunes [3]. Based on the models above and with field data collected from the well test separator of PUB-02 platform (Ubarana sea field) it was possible to demonstrate that the output gas flow of the separator can be estimate, with a reasonable precision, from the control signal of the Pressure Control Valve (PCV). Several models of the System Identification Toolbox from MATLAB® were analyzed to evaluate which one better fit to the data collected from the field. For validation of the models, it was used the AIC criterion, as well as a variant of the cross validation criterion. The ARX model performance was the best one to fit to the data and, this way, we decided to evaluate a recursive algorithm (RARX) also with real time data. The results were quite promising that indicating the viability to estimate the output gas flow rate from a plunger lift well producing to a well test separator, with the built-in information of the control signal to the PCV

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The purpose of this study was to develop a pilot plant which the main goal is to emulate a flow peak pressure in a separation vessel. Effect similar that is caused by the production in a slug flow in production wells equipped with the artificial lift method plunger lift. The motivation for its development was the need to test in a plant on a smaller scale, a new technique developed to estimate the gas flow in production wells equipped with plunger lift. To develop it, studies about multiphase flow effects, operation methods of artificial lift in plunger lift wells, industrial instrumentation elements, control valves, vessel sizing separators and measurement systems were done. The methodology used was the definition of process flowcharts, its parameters and how the effects needed would be generated for the success of the experiments. Therefore, control valves, the design and construction of vessels and the acquisition of other equipment used were defined. One of the vessels works as a tank of compressed air that is connected to the separation vessel and generates pulses of gas controlled by a on/off valve. With the emulator system ready, several control experiments were made, being the control of peak flow pressure generation and the flow meter the main experiments, this way, it was confirmed the efficiency of the plant usage in the problem that motivated it. It was concluded that the system is capable of generate effects of flow with peak pressure in a primary separation vessel. Studies such as the estimation of gas flow at the exit of the vessel and several academic studies can be done and tested on a smaller scale and then applied in real plants, avoiding waste of time and money.

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Purpose: This study involved an extensive search for randomized controlled clinical trials comparing bilateral balanced and canine-guided dentures, and questioned whether a bilateral balanced occlusion is imperative for successful denture treatment. Materials and Methods: Studies were identified by searching electronic databases (PubMed/MEDLINE, ISI Web of Science, LILACS, and BBD). The keywords “denture” and “occlusion” were used. The minimum inclusion requirements were (1) randomized controlled trials with patients of any age wearing both maxillary and mandibular conventional complete dentures (CDs), (2) comparison between bilateral balanced and canine-guided dentures, and (3) assessment of masticatory function and/or patients’ satisfaction. Results: The search resulted in the identification of 5166 articles. Subsequently, 5156 articles were excluded on the basis of title and abstract. By the end of the search phase, seven randomized controlled trials were considered eligible. Conclusions: Current scientific evidence suggests that bilateral balanced occlusion is not imperative for successful treatment with conventional CDs in average patients. More studies are necessary to identify if specific clinical conditions may benefit from a balanced occlusion.

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The maintenance of masticatory function is especially important for patients wearing complete dentures due to their limitations. Thus, the bilateral balanced occlusal concept is used to achieve greater masticatory efficiency. However, a critical review of the literature reveals that there is not sufficient scientific evidence to support bilateral balanced occlusion as the most appropriate occlusal concept in complete dentures. Therefore, the aim of this study was to evaluate the masticatory efficiency in complete dentures wearers with bilateral balanced occlusion and canine guidance. A double-blinded controlled crossover clinical trial was conducted. The sample was composed by 24 edentulous patients who wore sets of complete dentures with both occlusal concepts during equal periods of 3 months. Objective data were collected through the masticatory efficiency test performed by the colorimetric method with the beads, in which capsules of a synthetic material enclosing fuchsine-containing granules were used. Subjective data were recorded by patient's ratings of their chewing function. No significant statistical difference was found for masticatory efficiency (p=0.095) between the two occlusal concepts studied. The results suggest that bilateral balanced occlusion does not improve the masticatory efficiency in complete denture wearers.

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The maintenance of masticatory function is especially important for patients wearing complete dentures due to their limitations. Thus, the bilateral balanced occlusal concept is used to achieve greater masticatory efficiency. However, a critical review of the literature reveals that there is not sufficient scientific evidence to support bilateral balanced occlusion as the most appropriate occlusal concept in complete dentures. Therefore, the aim of this study was to evaluate the masticatory efficiency in complete dentures wearers with bilateral balanced occlusion and canine guidance. A double-blinded controlled crossover clinical trial was conducted. The sample was composed by 24 edentulous patients who wore sets of complete dentures with both occlusal concepts during equal periods of 3 months. Objective data were collected through the masticatory efficiency test performed by the colorimetric method with the beads, in which capsules of a synthetic material enclosing fuchsine-containing granules were used. Subjective data were recorded by patient's ratings of their chewing function. No significant statistical difference was found for masticatory efficiency (p=0.095) between the two occlusal concepts studied. The results suggest that bilateral balanced occlusion does not improve the masticatory efficiency in complete denture wearers.

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Ischemia and reperfusion of the small intestine disrupts gut barrier, causes bacterial translocation and activates inflammatory responses. An experimental study was planned to evaluate if 99mTc labelled Escherichia coli translocates to mesenteric lymph nodes, liver, spleen, lung and serum of rats submitted to mesenteric ischemia/reperfusion. Additionally, it was observed if the time of reperfusion influences the level of translocation. METHODS: Forty male Wistar rats underwent 45 minutes of gut ischemia by occlusion of the superior mesenteric artery. The translocation of labelled bacteria to different organs and portal serum was determined in rats reperfused for 30 minutes, 24 hours, sham(S) and controls(C), using radioactivity count and colony forming units/g (CFU). RESULTS: All the organs from rats observed for 24 hours after reperfusion had higher levels of radioactivity and positive cultures (CFU) than did the organs of rats reperfused for 30 minutes, C and S, except in the spleen (p<0,01). CONCLUSION: The results of this study indicated that intestinal ischemia/reperfusion led to bacterial translocation, mostly after 24 hours of reperfusion

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he present model of agriculture is based on intensive use of industrial inputs, due to its rapid response, but it brings harmful consequences to the environment, and it is necessary the use of modern inputs. And an alternative is the use of rock biofertilizers in agriculture, a product easy to use, with higher residual effect and does not harm the environment. The objective of study was to evaluate the inoculation and co-inoculation of different microorganisms in the solubilization of rock phosphate and potash ground microbial evaluating the best performance in the production of biofertilizers comparing with rocks pure in soil chemical properties and, verify effect of inoculation of the bacterium Paenibacillus polymyxa in the absorption of minerals dissolved in the development of cowpea (Vigna unguiculata [L.] Walp.). The first bioassay was conducted in Laboratory (UFRN) for 72 days in Petri dishes, where the rock powder was increased by 10% and sulfur co-inoculated and inoculated with bacterial suspension of Paenibacillus polymyxa grown in medium tryptone soy broth, Ralstonia solanacearum in medium Kelman, Cromobacterium violaceum in medium Luria-Bertani and Acidithiobacillus thiooxidans in medium Tuovinen and Kelly,and fungi Trichoderma humatum and Penicillium fellutanum in malt extract. Every 12 days, samples were removed in order to build up the release curve of minerals. The second bioassay was conducted in a greenhouse of the Agricultural Research Corporation of Rio Grande do Norte in experimental delineation in randomized block designs, was used 10 kg of an Yellow Argissolo Dystrophic per pot with the addition of treatments super phosphate simple (SS), potassium chloride (KCl), pure rock, biofertilizers in doses 40, 70, 100 and 200% of the recommendation for SS and KCl, and a control, or not inoculated with bacteria P. polymyxa. Were used seeds of cowpea BRS Potiguar and co-inoculated with the bacterial suspension of Bradyrhizobium japonicum and P. polymyxa. The first crop was harvested 45 days after planting, were evaluated in the dry matter (ADM), macronutrients (N, P, K, Ca, Mg) and micronutrients (Zn, Fe, Mn) in ADM. And the second at 75 days assessing levels of macro end micronutrients in plants and soil, and the maximum adsorption capacity of P in soil. The results showed synergism in co-inoculations with P. polymyxa+R. solanacearum and, P. polymyxa+C. violaceum solubilizations providing higher P and K, respectively, and better solubilization time at 36 days. The pH was lower in biofertilizers higher doses, but there was better with their addition to P at the highest dose. Significant reduction of maximum adsorption capacity of phosphorus with increasing dose of biofertilizer. For K and Ca was better with SS+KCl, and Mg to pure rock. There was an effect of fertilization on the absorption, with better results for P, K and ADM with SS+KCL, and N, Ca and Mg for biofertilizers. Generally, the P. polymyxa not influence the absorption of the elements in the plant. In treatments with the uninoculated P. polymyxa chemical fertilizer had an average significantly higher for weight and number of grains. And in the presence of the bacteria, biofertilizers and chemical fertilizers had positive values in relation to rock and control. The data show that the rocks and biofertilizers could meet the need of nutrients the plants revealed as potential for sustainable agriculture

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The people of Ceará state are descended from miscegenation between the Portuguese colonizers and the native population, resulting in a different facial pattern from other populations. It is important that this pattern be thoroughly understood, along with its minimum and maximum values so that they can be assessed and respected, allowing professionals who deal with the craniofacial complex to work more efficiently and scientifically. Aim: To characterize the morphological pattern of individuals from Ceará state, whose father and grandfather are also native from Ceará, in the 10-12 year age group, not submitted to previous orthodontic treatment, in order to determine: 1) the prevalence of occlusal pattern; 2) the prevalence of dental anomalies (DA) and, 3) the skeletal and dental cephalometric characteristics of individuals that present with normal occlusion and harmonious facial pattern. Methodology: A list of 10-12 year-olds was obtained from 515 schools containing 162,713 students (Education Secretariat of Ceará State), from which 234 individuals were examined (107 boys and 157 girls). The assessment criteria adopted were: 1) Angle s Classification System to determine occlusal pattern. The occlusal characteristics were measured through overbite, overjet, crowding and interincisal diastema. 2) DA are anomalies of number, shape, size, eruption and structure and, 3) in the group that presented with normal occlusion, we used cephalometric analysis measures proposed by Downs, Steiner, Tweed, Holdaway, Jacobson and McNamara. Results: 1) 25.8% of the schoolchildren had normal occlusion, 47.5% class I malocclusion, 22.3% class II malocclusion and 4.2% class III malocclusion. No statistically significant difference was found between the age group studied and sex. Thirty percent of the individuals had normal overbite, while 36.7% and 19.7% had increased and reduced overbite, respectively. Normal overjet was found in 33.7% of the individuals, increased overjet in 50% and reduced in 16.3%. Dental crowding was observed in 62.5% of the individuals and the presence of interincisal diastema in 14.8%. 2) The prevalence of DA was 56.1%, 6.8% in the number, 10.8% in shape, 4.1% in size, 34.5% in eruption, 26.4% in structure and 17.4% had more than one DA. No association was found between DA and sex, but DA was significantly associated to malocclusion (p<0.05); 3) there was no association between sex or facial type between the measures of nasal-labial angle, position and effective maxillary length, effective mandibular length and the sagittal relationship between the molars, overjet and overbite, position of upper incisors, lower incisors and between the incisors themselves. There was a difference between sex, on the VERT index and in lower anterior facial height, upper incisor inclination and line-H, between facial types for the occlusal plane angles, mandibular plane, facial axis, lower incisor inclination, mandibular position, upper incisor position, lower anterior facial height, ANB and line-H. It was concluded that: 1) the most prevalent occlusal type was class I malocclusion, with no distinction for sex or age group, and the assessment of occlusal characteristics showed that excessive overbite and overjet were the most predominant findings, along with a high occurrence of tooth crowding; 2) a high prevalence of DA was found, particularly eruption anomalies, not influenced by sex but significantly associated to malocclusion and 3) individuals from Ceará are predominantly brachyfacial, exhibiting a number of similarities inherent to their facial pattern, such as a convex profile, retracted jaw, reduced lower third and protruded lower incisors. This study was multidisciplinary, involving researchers from the areas of epidemiology, radiology and dentistry, thereby meeting the multidisciplinarity requirements of the Postgraduate Program in Health Sciences

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This study aimed to evaluate factors associated to orthodontic treatment stability and patient satisfaction in the long-term. A total of 209 patients (88 class I and 121 class II) treated with straight wire fixed appliance were selected at least 5 years post treatment. Six hundred twenty seven dental casts were examined with the PAR Index at pretreatment (T1), end of treatment (T2), and at long-term follow up (T3, mean 8.5 years post treatment). At T3, a Dental Impact on Daily Living questionnaire was used to assess patient satisfaction with the dentition in the long-term. Friedman test and multiple regression analysis were used to evaluate changes among the time points and factors associated with stability and patient satisfaction. Predictive factors used to exam the occlusion were: PAR Index at T1 and T2, age at T1, the amount of time without retainer, length of Hawley retainer wear, length of follow-up, sex, extraction and third molar status. To assess patient satisfaction were considered: changes produced by the orthodontic treatment (PAR T2-T1), post treatment stability (PAR T3), age at the start of treatment (T1), length of treatment (T2-T1), gender, and extraction. Orthodontic treatment produced a significant improvement of 94.2% in the PAR Index (T2-T1), but this change was not associated with the level of satisfaction when the patient was questioned at T3. No significant change was observed between T2 and T3. However, when the sample was divided according to the level of finalization (PAR T2), it was observed that well-finished patients experienced some deterioration (P<.001), whereas the less well-finished ones showed some improvement (P<.05). Even with the deterioration, the well-finished patients still had a better PAR Index at T3 compared to the less well-finished ones (PAR T2- T3). Regression analysis showed that PAR Index at T1 and T2, age at T1, and length of retainer wear had a slight association with occlusal stability (R2 = 0.27). Patient satisfaction was significantly associated only with PAR Index at T3 (r2=0.125, P<.0001). We can conclude that, even thought orthodontic treatment is quite stable, not so well-finished treatments tend to show some improvement and well-finished ones deteriorate some in the long-term. Despite of that, well-finished patients still have better occlusal characteristics. Patient satisfaction is not related to the result of orthodontic treatment; nevertheless, there is a slight association with dentition in the long-term

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The pressure ulcers (PU), also known as decubitus ulcers, are defined as injuries caused by the constant pressure exerted on a particular point of the body, causing impairment of blood supply with a decrease or interruption of tissue irrigation, causing occlusion of blood vessels and capillaries, ischemia and cell death. This is a descriptive study with longitudinal design, and panel type, with quantitative approach that aimed to examine the association between predisposing conditions (PC), intrinsic factors (IF) and extrinsic factors (EF) with the occurrence of PU, in hospitalized patients in the Intensive Care Unit (ICU), pain clinical, surgical clinical and neurology wards of a university hospital. The study population was composed of all patients who were restricted to bed during the period from December 2007 to February 2008. The study was approved by the Ethics Committee of HUOL / UFRN (No 135/07). The data-collection took place through a structured formulary of observation, data from medical records and physical examination of patients skins. The results were organized in SPSS 15.0 software, tabulated, categorized and analyzed by descriptive and inferential statistics. Of the 30 patients studied, 43.3% had been hospitalized in the pain clinical and surgical clinic wards, 20.0% in the ICU, 20.0% in the ICU / ward and 16.7% in neurology, being the length of hospitalization in those units of 7 to 18 days (63.3%) and from 19 to 30 days (36.7%), predominantly female and aged ≥ 60 years (60.0%). 19 PU were diagnosed in 43.3% of patients monitored, being 38.5% with one PU between 7 to 18 days and 46.2% with two or more between 19 to 30 days of hospitalization, showing significant relationship (ρ-value = 0029) between length of hospital stay and the number of PU. Was found an association of 35.7% of the PC (cardio-respiratory, hematological, metabolic and psychogenic), IF (age group, oedema, skin changes in humidity and change of body temperature) and EF (type of mattress and strength of body pressure) for all patients studied, statistically significant (ρ-value = 0001), between the average scores in patients with and without PU, with reason chance to 12.0 for the development of PU and there was moderate correlation ( r = 0618) in the presence of this association. Results show the influence of the multiplicity of factors and conditions on the occurrence of PU, which brings us to reflect on the assistance focused on prevention and reduction of these injuries which will encourage the reduction of hospitalization length, physical and psychological suffering, and the possibility of improving the clinical condition of the patient.

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Among the pests that attack corn crop in Brazil, there is Spodoptera frugiperda (JE Smith, 1797) (Lepidoptera: Noctuidae), known as fall armyworm, which is the major corn pest. Due to genetic instability during serial passage of baculoviruses in insect cell culture, the viral bioinseticides in vitro production development is the greatest challenge for mass production of this bioproduct. Successive passages of virus using extracellular viruses (BVs), necessary during viral bioinseticides production scaling up, leads to the appearance of aberrant forms of virus, a process so called as "passage effect ". The main consequence of passage effect is the production of occlusion bodies (OB) decrease, preventing its production using in vitro process. In this study, it was carried out a serial passage of baculovirus Spodoptera frugiperda multiple nucleopolyhedrovirus, isolate 18, using Sf21 cells. A decrease in the production of occlusion bodies from 170 to 92 in the third to fourth passage was observed. A factorial experimental design (22) was employed to verify the influence of two input variables, concentration of the hormone 20 - hydroxyecdysone (CH) and cholesterol (CC) on the values of response variables (volumetric and the specific OB production) of the process, seeking to define the optimum operating ranges trying to reverse or minimize the passage effect. The result indicated a negative influence of the cholesterol addition and positive effect in the hormone supplementation which the optimum range found for the concentrations studied were 8 to 10μg/mL and 5 to 6.5 mg / mL, for cholesterol and hormone concentrations respectively. New experiments were performed with addition of hormone and cholesterol in order to check the influence of these additives on the OB production independently. While the best result obtained from the factorial experiment was 9.4 x 107 OB/mL and 128.4 specific OB/cell, with the addition of only 6μg/mL 20-hydroxyecdysone these concentrations increased to 1.9 x 108 OB/mL and 182.9 OB/cell for volumetric and specific OB production, respectively. This result confirms that the addition of the hormone 20-hydroxyecdysone enhances the SfMNPV in vitro production process performance using Sf21 cells

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The maintenance of masticatory function is especially important for patients who wear complete dentures due to the limitations of this type of prosthesis. Thus, the bilateral balanced occlusion (BBO) is used to achieve, besides other advantages, greater masticatory efficiency. However, analyzing critically the literature, it is observed that there is not enough scientific evidence that support the BBO as the most appropriate occlusal concept in complete dentures. This way, the purpose of the present study was to verify if complete dentures wearers with BBO present better masticatory efficiency and capacity than those with canine guidance (CG). A double-blind controlled crossover clinical trial was conducted. The sample was made of 24 completely edentulous patients. The subjects wore sets of complete dentures with both occlusal concepts for equal periods of 3 months. Objective data were collected through the masticatory efficiency test, performed by the colorimetric method, in which capsules of a synthetic material enclosing fuchsine- containing granules were used. Subjective data were recorded by patient´s ratings of their chewing function, which is the masticatory ability. No significant statistical difference was found for masticatory efficiency (p=0,0952) and masticatory ability (x2=0,5711/ p=0,4498) between the two occlusal concepts studied, as well as there was no correlation between these two variables (p=0,2985). Based on these results, it seems reasonable to use CG for the setup of complete dentures, since it is an easier and quicker technical procedure, until that future researches can come to complement this question

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The vascular segmentation is important in diagnosing vascular diseases like stroke and is hampered by noise in the image and very thin vessels that can pass unnoticed. One way to accomplish the segmentation is extracting the centerline of the vessel with height ridges, which uses the intensity as features for segmentation. This process can take from seconds to minutes, depending on the current technology employed. In order to accelerate the segmentation method proposed by Aylward [Aylward & Bullitt 2002] we have adapted it to run in parallel using CUDA architecture. The performance of the segmentation method running on GPU is compared to both the same method running on CPU and the original Aylward s method running also in CPU. The improvemente of the new method over the original one is twofold: the starting point for the segmentation process is not a single point in the blood vessel but a volume, thereby making it easier for the user to segment a region of interest, and; the overall gain method was 873 times faster running on GPU and 150 times more fast running on the CPU than the original CPU in Aylward

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Fungi of the family Nidulariaceae or bird s nest fungi present a vase-shaped basidiomata with the wall surface smooth or striated lengthwise and internal structures resembling small bird eggs in a nest, the peridioles. Among the five genera that comprise the group, the more representative is Cyathus Haller: Pers. The Brazilian Northeast region shows major importance for the world s diversity by containing a Brazilian unique and exclusively phytoecological domain, the Caatinga, which lacks particular attention regarding macrofungi. Although the gradual growth of knowledge in recent years, studies are still insipient in the Caatinga domain. Between their various vegetal formations are the Brejos de Altitude , described as islands with moist perennial vegetation, low soil fertility and annual precipitation of 900 1.300 mm. This study aimed to evaluate the taxonomic richness of Nidulariaceae fungi in Caatinga s areas of Northeastern Brazil, describing and identifying species, as well as expanding the collection of Herbarium UFRN Fungos. For description of Nidulariaceae fungi was followed the proposed by specialized literature in the group. We have found and described 10 species of the genus Cyathus, namely: C. earlei Lloyd, C. gayanus Tul. & C. Tul., C. gracilis H.J. Brodie, C. intermedius (Mont.) Tul. & C. Tul., C. limbatus Tul. & C. Tul., C. montagnei Tul. & C. Tul., C. pallidus Berk. & M.A. Curtis, C. poeppigii Tul. & C. Tul., C. striatus (Huds.) Willd. and C. tríplex Lloyd. Beyond these have been described four new species to science: Cyathus calvescens R. Cruz & Baseia sp. nov., C. hortum R. Cruz & Baseia sp. nov., C. magnomuralis R. Cruz & Baseia sp. nov. and C. parvocinereus R. Cruz & Baseia sp. nov. Two samples were identified only to genus level. No member of Mycocalia J.T. Palmer, Nidula V.S. White, Nidularia Fr. and Crucibulum Tul. & C. Tul. has been found, however the results were extremely valuable for being an unprecedented work in Caatinga, and importante tool for implementation of conservation projects and sustainable utilization of this domain

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Societal concerns about environmental sustainability has lead to the development of ecologically-friendly alternatives to chemical insecticides for crop protection. One such alternative is biological pest control. In particular, baculoviruses are well suited as insect biopesticides due to their narrow host specificity and relative ease of propagation. In Brazil, the baculovirus Anticarsia gemmatalis nucleopolyhedrovirus (AgMNPV) is the main biological control agent employed for the soybean pest, Anticarsia gemmatalis. This baculovirus biopesticide is currently produced using caterpillars, but increasing market demand for the product has encouraged the development of an in vitro manufacturing process, which can be scaled up to much higher virus productivities. In this study, three wild-type AgMNPV isolates (AgMNPV-2D, AgMNPV-MP2 and AgMNPV-MP5) and a recombinant form (vAgEGT-LacZ) were characterised in terms of occlusion body (OB) production and infection kinetics, to enable future optimisation of the in vitro production process. These viruses were propagated using a Spodoptera frugiperda (IPLB-SF21) insect cell line grown in shaker-flask batch cultures. Among the virus isolates tested, AgMNPV-MP5 was found to be the best producer, yielding (5.3±0.85)x108 OB/mL after 8 days post infection. The characterisation of vAgEGT-LacZ propagation in suspension cell cultures has not been previously reported in the literature; hence it became the main focus for this thesis. In particular, it was carried out a study on the effect of the multiplicity of infection (MOI) on OB production. Five successive batches were performed getting a final production (8.9±1.42)x1014 occlusion bodies, considering that production is related for a bioreactor with final volume of 10m3. A low MOI associated with a fed-batch process for vAgEGT-LacZ production was found to support a 3-fold higher OB yield when compared to the default batch process (1.8x107 and 5.3x107 OB/mL, respectively). This yield is competitive with regards to the production process.