<p>Northern Central America is a tectonically complex zone defined by its borders with Cocos and North America plates. The Middle America subduction zone and the strike-slip motion along the North America-Caribbean plate boundary, in that order, control most of its deformation. The interaction between the different elements of the studied area is evident from the high seismicity in the region, especially along plate boundaries. Also in the interior of the region, seismicity shows that deformation takes place, though in lesser degree. In a time window of 30 years, three earthquakes with moment magnitude larger than 7 struck northern Central America evincing the need to estimate the seismic hazard for the zone. To tackle the problem, we compiled a catalogue of hypocenters commencing in 1964, defined seismogenic sources and described the evolution of earthquake activity through a Poisson model. Probabilistic seismic hazard (PSH) calculations for the next 50 years were performed. The highest estimate of seismic hazard was obtained for the zone adjacent to the subduction zone. Because of the fundamental importance of demarcating seismogenic sources in the PSH analysis, i.e. defining the seismotectonic model, we extended the catalogue to cover 102 years for the whole northern Central America. We have studied the North America-Caribbean plate boundary in order to refine the fault representation. Different techniques were used, like that of body-waveform modeling, allowing us to limit the extent of depth of faulting to 20 km. The seismic moment tensor was used to estimate the deformation velocities on known tectonic structures, including those of the Honduras depression and borderland faults. Finally, we made use of the Coulomb stress criterion to determine the relation between earthquake occurrence and static stress changes following major earthquakes.</p>

<p>Living kidney donation is a clinical situation with unique features in the sense that healthy individuals voluntarily expose themselves to certain risks and inconveniences. Therefore, eliminating as much of the associated discomfort as possible is crucial. The primary aim of this study was to evaluate whether it is possible to use the examination with computed tomography (CT), which is essential to the investigation, also for determining the ratio of the two kidneys’ function – the split renal function. If possible, an examination with gamma camera renography could be excluded from the work-up. </p><p>To investigate this possibility, 27 subjects who had underwent CT and renography as part of kidney donor investigation were studied retrospectively. The quantity of contrast material in each kidney was considered proportional to that kidney’s function, and measurement was made in each of the two available contrast phases. The results were compared to the results from renography. A similar analysis was conducted in 38 patients investigated for suspected renal artery stenosis with CT and renography, including a study of an automatized method for the acquisition of data from CT. For further scrutiny, a respiratory triggered dynamic contrast-enhanced magnetic resonance imaging (MRI) examination was investigated in 26 individuals. Results of split renal function were compared with renography and with CT in a subgroup. To study the possibility of facilitating the data analysis with CT, a formula for approximation of the contrast attenuation was studied in 64 subjects. An analysis of the significance of choice of contrast phase was also conducted in 43 subjects. </p><p>Unsatisfactory agreement with renography resulted from the CT analysis of previous donors, partly due to technical shortcomings. However, the technique was recognized to have a potential value. In the subsequent material, the settings were improved, with beneficial effects on the agreement. Respiratory-triggered MRI generated high quality examinations of renal uptake and excretion, with results harmonizing well with renography and CT. The approximation formula applied to CT resulted in higher accuracy for renal volume assessment than with the automatic method, and an acceptable agreement of the split renal function estimate. </p><p>From the presented results, a revision of the current donor investigation protocol is suggested. CT gives sufficient information to exclude renography as a routine examination. In cases of uncertainty, renography is recommended for secondary evaluation.</p>

Living kidney donation is a clinical situation with unique features in the sense that healthy individuals voluntarily expose themselves to certain risks and inconveniences. Therefore, eliminating as much of the associated discomfort as possible is crucial. The primary aim of this study was to evaluate whether it is possible to use the examination with computed tomography (CT), which is essential to the investigation, also for determining the ratio of the two kidneys’ function – the split renal function. If possible, an examination with gamma camera renography could be excluded from the work-up. To investigate this possibility, 27 subjects who had underwent CT and renography as part of kidney donor investigation were studied retrospectively. The quantity of contrast material in each kidney was considered proportional to that kidney’s function, and measurement was made in each of the two available contrast phases. The results were compared to the results from renography. A similar analysis was conducted in 38 patients investigated for suspected renal artery stenosis with CT and renography, including a study of an automatized method for the acquisition of data from CT. For further scrutiny, a respiratory triggered dynamic contrast-enhanced magnetic resonance imaging (MRI) examination was investigated in 26 individuals. Results of split renal function were compared with renography and with CT in a subgroup. To study the possibility of facilitating the data analysis with CT, a formula for approximation of the contrast attenuation was studied in 64 subjects. An analysis of the significance of choice of contrast phase was also conducted in 43 subjects. Unsatisfactory agreement with renography resulted from the CT analysis of previous donors, partly due to technical shortcomings. However, the technique was recognized to have a potential value. In the subsequent material, the settings were improved, with beneficial effects on the agreement. Respiratory-triggered MRI generated high quality examinations of renal uptake and excretion, with results harmonizing well with renography and CT. The approximation formula applied to CT resulted in higher accuracy for renal volume assessment than with the automatic method, and an acceptable agreement of the split renal function estimate. From the presented results, a revision of the current donor investigation protocol is suggested. CT gives sufficient information to exclude renography as a routine examination. In cases of uncertainty, renography is recommended for secondary evaluation.

Ecdysis triggering hormone (ETH) is a neuropeptide known for its role in the orchestration of ecdysis. However, its role in the regulation of Juvenile Hormone (JH) synthesis is unknown. In Aedes aegypti, JH is synthesized by the corpora allata (CA) and titers are tightly regulated by allatoregulatory factors. In this study I describe the effect of ETH on JH synthesis during the late pupal stage and in the adult female after blood feeding. Analysis of ETH receptor (ETHRs) expression showed that ETHRs are present in both the CA and the corpora cardiaca (CC), a neurohemal organ. The data suggest that ETH regulates JH synthesis directly through its receptors in CA. Our results show that in pupa, ETH has a stimulatory effect on JH synthesis while in adult blood fed females, ETH is inhibitory. These findings constitute the first evidence of ETH as a regulatory peptide in mosquito JH synthesis.

This Ph.D. dissertation focuses on a comprehensive study of seismic waveform similarity aiming at two themes: (1) reliable identification of repeating earthquakes (repeaters) and (2) investigation of the detailed source process of induced seismicity through the three-dimensional spatiotemporal evolution of mainly neighbouring earthquakes. Theme 1: Reliable identification of repeaters. Repeaters, occurring repeatedly on the same fault patch with nearly identical waveforms, are usually identified with the match-filtering (MF) method which essentially measures the degree of waveform similarity between an earthquake pair through the corresponding cross-correlation coefficient (CC). However, the performance of the MF method can be severely affected by the length of the cross‐correlation window, the frequency band of the applied digital filter, and the presence of a large‐amplitude wave train. To optimize the performance of MF, I first examine the effects of different operational parameters and determine generic rules for selecting the window length and the optimal frequency passband. To minimize the impact of a large‐amplitude wave train, I then develop a new method, named the match-filtering with multisegment cross-correlation (MFMC) method. By equally incorporating the contributions from various segments of the waveforms, the new method is much more effective in capturing the minor waveform discrepancy between an event pair due to location difference and hence is more reliable in detecting potential repeaters and discriminating non-repeaters with large inter-event separation. With both synthetic and borehole array waveform data, I further reveal that waveform similarity is controlled by not only the inter-event separation but also many other factors, including station azimuth, epicentral distance, velocity structure, etc. Therefore, in contrast to the traditional view, the results indicate that waveform similarity alone is insufficient to unambiguously identify true repeaters. For reliable repeater identification, we should rely on a physics-based approach considering both the overlapped source area and magnitude difference. Specifically, I define an event pair to be true repeaters if their inter-event separation is smaller than the rupture radius of the larger event and their magnitude difference is no more than 1. For the precise estimation of inter-event distance in cases of limited data, I develop the differential traveltime double-difference (DTDD) method which relies on the relative S-P differential traveltime. The findings of this study imply that previously identified repeaters and their interpretations/hypotheses potentially can be biased and hence may need a systematic reexamination. Theme 2: Investigation of the detailed source process of induced seismicity. Earthquakes induced by hydraulic fracturing (HF), especially those with large magnitudes, are often observed to have occurred near/after well completion. The delayed triggering of induced seismicity with respect to injection commencement poses serious challenges for risk mitigation and hazard assessment. By performing waveform cross-correlation and hierarchical clustering analysis, I reveal a high-resolution three-dimensional source migration process with mainshock delayed triggering that is probably controlled by local hydrogeological conditions. The results suggest that poroelastic effects might contribute to induced seismicity but are likely insufficient to activate a non-critically stressed fault of sufficient size. My analysis shows that the rapid pore-pressure build-up from HF can be very localized and capable of producing large, felt earthquakes on non-critically stressed fault segments. I further infer that the number of critically stressed, large intraplate faults should be very limited, and that reactivation of such faults may require sufficient pore-pressure accumulation. The findings of this study may also explain why so few fluid injections are seismogenic. / Graduate

Deep soil mixing to construct stiff columns is one of the methods used today to improve performance of loose ground and remediate liquefaction problems. This research adopts a numerical approach to study seismic performance of soil-cement columnar reinforcements in loose sandy profiles. Different constitutive models were investigated in order to find a model that can properly predict soil behavior during seismic excitations. These models included NorSand, Dafalias-Manzari, Plasticity Model for Sands (PM4Sand) and Pressure-Dependent-Multi-Yield-02 (PDMY02) model. They were employed to predict behavior of soils with different relative densities and under different confining pressures during monotonic and cyclic loading. PDMY02 was identified as the most suitable model to represent soil seismic behavior for the system studied herein. The numerical aspects of the finite element approach were investigated to minimize the unintended numerical miscalculations. The focus was put on convergence tolerance, solver time-step, constraint definition, and, integration, material and Rayleigh damping. This resulted in forming a robust numerical configuration for 3-D nonlinear models that were later used for studying behavior of the reinforced grounds. Nonlinear finite element models were developed to capture the seismic response of columnar reinforced ground during dynamic centrifuge testing. The models were calibrated with results from tests with unreinforced profiles. Thereafter, they were implemented to predict the response of two reinforced profiles during seismic excitations with different intensities and liquefaction triggering. Model predictions were compared with recordings and the possible effects from the reinforcements were discussed. Finally, parametric studies were performed to further evaluate the efficiency of the reinforcements with different extension depths and area replacement ratios. The results collectively showed that the stiff elements, if constructed appropriately, can withstand seismic excitations with different intensities, and provide a firm base for overlying structures. However, the presence of the stiff elements within the loose ground resulted in stronger seismic intensities on the soil surface. The columns were not able to considerably reduce pore water pressure generation, nor prevent liquefaction triggering. The reinforced profiles, comparing to the free-field profiles, had larger settlements on the soil surface but smaller settlements on the columns. The results concluded that utilization of the columnar reinforcements requires great attention as these reinforcements may result in larger seismic intensities at the ground surface, while not considerably reducing the ground deformations. / Ph. D.

We implement a state-of-the-art question answering system based on Convolutional Neural Networks and Attention Mechanisms and include four different variants of answer triggering that have been discussed in recent literature. The mechanisms are included in different places in the architecture and work with different information and mechanisms. We train, develop and test our models on the popular SQuAD data set for Question Answering based on Reading Comprehension that has in its latest version been equipped with additional non-answerable questions that have to be retrieved by the systems. We test the models against baselines and against each other and provide an extensive evaluation both in a general question answering task and in the explicit performance of the answer triggering mechanisms. We show that the answer triggering mechanisms all clearly improve the model over the baseline without answer triggering by as much as 19.6% to 31.3% depending on the model and the metric. The best performance in general question answering shows a model that we call Candidate:No, that treats the possibility that no answer can be found in the document as just another answer candidate instead of having an additional decision step at some place in the model's architecture as in the other three mechanisms. The performance on detecting the non-answerable questions is very similar in three of the four mechanisms, while one performs notably worse. We give suggestions which approach to use when a more or less conservative approach is desired, and discuss suggestions for future developments.

Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2016-10-18T22:30:52Z No. of bitstreams: 1 DISSERTA??O TACIANE.pdf: 1332823 bytes, checksum: 16624f495ae47a3674ddd9369197c8bf (MD5) / Made available in DSpace on 2016-10-18T22:30:52Z (GMT). No. of bitstreams: 1 DISSERTA??O TACIANE.pdf: 1332823 bytes, checksum: 16624f495ae47a3674ddd9369197c8bf (MD5) Previous issue date: 2015-03-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Metabolic syndrome is a set of changes consisting of dyslipidemia, glucose intolerance, hypertension, obesity and hyperinsulinemia. The study of this syndrome is of great importance to public health, since it can lead to negative outcomes that could increase their risk of cardiovascular disease in the general population. OBJECTIVE: Investigate the occurrence of metabolic syndrome and associated factors in adults treated in public health services in the city of Feira de Santana - BA. METHOD: epidemiological study, cross-sectional and exploratory conducted in 479 adults aged at least 20 years, seen at public health services in the fair city of Santana - BA. Information was obtained through structured questionnaires, anthropometric clinical and oral, and biochemists. The diagnosis of metabolic syndrome took into account the criteria proposed by the National Cholesterol Education Program - Adult Treatment Panel III / (NCEP-ATP III) and the International Diabetes Federation (IDF). Prevalence ratios were estimated (PR) and their respective confidence intervals of 95% (95% CI) and statistical significance level of 5%. Multivariate analysis was constructed using Poisson regression. RESULTS: Presented in the form of a scientific paper: "Metabolic syndrome and its associated factors in adults", to be submitted to the Journal Brazilian Archives of Endocrinology and Metabolism. The occurrence of MS ranged from 57% (NCEP / ATP III) to 62% (IDF). In the bivariate analysis female, advanced age, overweight, and some comorbidities proved to be independently associated with MS. In the hierarchic analysis, only BMI ? 30 kg / m? (NCEP-ATPIII) and no measurement of blood pressure periodically (IDF) remained independently associated with metabolic syndrome. CONCLUSIONS: The metabolic syndrome is a public health problem among individuals in this study. The body mass index ? 30 kg / m2 not regular blood pressure measurements are important predictors of the metabolic syndrome in adults. / A S?ndrome Metab?lica ? um conjunto de altera??es constitu?do por dislipidemia, intoler?ncia ? glicose, hipertens?o arterial, obesidade e a hiperinsulinemia. O estudo desta s?ndrome ? de grande relev?ncia para a sa?de p?blica, uma vez que pode ocasionar desfechos negativos capazes de aumentar o risco de doen?as cardiovasculares na popula??o em geral. OBJETIVO: Investigar a ocorr?ncia de S?ndrome Metab?lica e seus fatores associados em indiv?duos adultos atendidos em servi?os de sa?de p?blica no Munic?pio de Feira de Santana ? BA.M?TODO: Estudo epidemiol?gico, transversal, e de car?ter explorat?rio realizado em 479 adultos com idade m?nima de 20 anos, atendidos em servi?os de sa?de p?blica no munic?pio de Feira de Santana ? BA. As informa??es foram obtidas mediante aplica??o de question?rios estruturados, exames cl?nicos antropom?tricos e bucais, e bioqu?micos. O diagn?stico da s?ndrome metab?lica levou em considera??o os crit?rios propostos pelo National Cholesterol Education Program - Adult Treatment Panel III / (NCEP-ATP III) e pela Internacional Diabetes Federation (IDF). Foram estimadas raz?o de preval?ncia (RP) e seus respectivos intervalos de confian?a de 95% (IC 95%) e n?vel de signific?ncia estat?stica de 5%. A an?lise multivariada foi constru?da usando a regress?o de Poisson. RESULTADOS:Apresentados em forma de artigo cient?fico: ?S?ndrome metab?lica e seus fatores associados em indiv?duos adultos?, a ser submetido ? Revista Arquivos Brasileiros de Endocrinologia e Metabologia. A ocorr?ncia da SM variou entre 57% (NCEP/ATP III) a62% (IDF). Na an?lise bivariada, sexo feminino, faixa et?ria avan?ada, excesso de peso, e algumas comorbidades mostraram-se independentemente associados com SM. Na an?lise hierarquizada, apenas ?ndice de massa corporal ? 30kg/m? (NCEP-ATPIII) e n?o aferi??o da press?o arterial periodicamente (IDF)permaneceram independentemente associados ? s?ndrome metab?lica.CONCLUS?ES: A s?ndrome metab?lica representa um problema de Sa?de P?blica entre os indiv?duos desse estudo. O ?ndice de massa corporal ? 30kg/m2 a n?o aferi??o regular da press?o arterial s?o potenciais preditores da s?ndrome metab?lica em adultos.

Les crues – telles que les laves torrentielles – engendrées dans les torrents lors de fortes précipitations peuvent mobiliser de grande quantité de sédiments. Lorsqu'elles atteignent les zones urbanisées, elles peuvent mettre en dangers à la fois les personnes et les biens. Les approches visant à réduire le risque torrentiel se basent largement sur des seuils intensité-durée de pluie qui déterminent les conditions minimum de déclenchement d’une lave torrentielle. Pourtant, ces seuils sont sujets à une forte variabilité liée, non seulement aux différences inter-sites, mais aussi à la méthode appliquée lors de leur établissement. De plus, ils peuvent entraîner des fausses prédictions, l’intensité et la durée de l’épisode de pluie n’étant pas les seules variables explicatives. Ce travail de thèse vise (i) à fournir un cadre méthodologique rigoureux pour l’établissement des seuils de pluie afin de limiter les sources de variabilité, et (ii) à améliorer leurs performances en considérant à la fois les facteurs de déclenchement et de prédisposition. Il s’appuie sur les données d’un observatoire des crues torrentielles, mis en place dans les Alpes françaises en 2011 sur les torrents très actifs du Manival et du Réal. Dans un premier temps, les images et mesures hautes-fréquences collectées entre 2011 et 2016 ont été analysées afin de détecter et de caractériser les crues torrentielles. Pour appréhender la diversité des écoulements observés, une classification phénoménologique a été proposée. Dans un second temps, la condition minimum intensité-durée de pluie requise pour déclencher une lave torrentielle a été établie. La sensibilité du seuil à la définition d’un épisode de pluie a été évaluée. Dans un troisième temps, un modèle de régression logistique a été implémenté pour discriminer les épisodes de pluies critiques qui n’ont pas engendré de lave torrentielle. Il a permis de sélectionner les variables explicatives les plus pertinentes. Finalement, des pistes de travail ont été avancées pour (i) passer de conditions critiques établies à une échelle locale vers une échelle régionale, en perspective d’une application au sein d’un système d’alerte dédié aux risques hydrométéorologiques, et (ii) passer des conditions de déclenchement d’une lave torrentielle dans la zone de production sédimentaire aux conditions de propagation jusqu'aux zones à enjeux. / Flows – such as debris flows – caused by heavy rainfalls in torrents can mobilise a huge amount of sediments. When they reach the urbanised areas, they may endanger the people’s safety or cause damages. Approaches aimed at mitigating torrential risk widely rely on rainfall intensity-duration thresholds which determine the minimum debris-flow triggering conditions. However, these thresholds suffer from a high variability related not only to inter-site differences but also to the method applied to design them. In addition, they are likely to cause false prediction because the intensity and the duration of the rainfall event are not the only explanatory variables. This PhD research work aim (i) to provide a rigorous methodological framework for designing rainfall threshold in order to limit the variability sources, and (ii) to improve their performances by including both the triggering and the predisposing factors. It is supported by field observations stemming from high-frequency monitoring stations installed since 2011 on two very active debris flow-prone torrents in the French Alps: the Manival and the Réal. First, the images and data gathered between 2011 and 2016 were analysed in order to detect and characterise the sediment laden-flows. To deal with the variety of recorded flows, a phenomenological classification was performed. Second, the minimum intensity-duration threshold for debris-flow triggering was assessed. The threshold sensitivity to the rainfall event definition was estimated. Third, a logistic regression model was used to discriminate the critical rainfall events which do not lead to a debris flow. It makes it possible to select the most relevant explanatory variables. At last, several avenues of work were proposed (i) to move the knowledge of debris-flow initiation conditions from a local to a regional level, with a view to application in a warning system dedicated to hydrometeorological risks, and (ii) to improve the ability to predict, not the debris-flow triggering in the production zone, but the debris-flow propagation up to the area concerned.

Base teórica: A meningite bacteriana é uma causa importante de morbidade e mortalidade na infância. Análise do líquido cefalorraquidiano (LCR) continua a ser a ferramenta de diagnóstico padrão ouro, porém novos biomarcadores para o diagnóstico e prognóstico ainda são necessários. Receptor Desencadeador Expresso nas Células Mielóides Tipo 1 (TREM-1) é um receptor transmembrana expresso em neutrófilos e monócitos, que desempenha um papel importante na modulação da resposta inflamatória. A sua fração solúvel (sTREM-1) também é aumentada na infecção, inflamação ou doenças imunológicas. Neste estudo nós avaliamos, prospectivamente, o valor do TREM-1 como um biomarcador de meningite bacteriana aguda em pacientes pediátricos e sua possível utilização como uma ferramenta de prognóstico neste cenário. Objetivos: O objetivo primário do presente estudo é caracterizar os níveis líquóricos solúveis de TREM-1 (sTREM-1) em pacientes admitidos por suspeita clínica de meningite. Analisamos também os níveis de sTREM-1 nos casos de meningite bacteriana e viral, além de medir a sensibilidade e especificidade deste biomarcador no LCR e estudar se esse biomarcador pode ser um fator associado ao prognóstico em meningite bacteriana aguda. Métodos: Sessenta e um pacientes pediátricos, de 0 a 10 anos foram avaliados quanto à meningite e foram prospectivamente incluídos neste estudo. Na admissão, após a suspeita clínica de meningite foram submetidos à análise do LCR para o diagnóstico e uma amostra do LCR inicial foi utilizado também para análise do sTREM-1. Os pacientes foram acompanhados durante a sua internação com o registro de seu tratamento e desfecho clínico para posterior análise dos dados. Resultados: Dentre os 61 pacientes, 38 (62%) foram negativos para a meningite, 7 (11%) pacientes foram diagnosticados com meningite viral e 16 (27%) pacientes foram diagnosticados com meningite bacteriana aguda e recebeu tratamento direcionado. Sexo (p = 0,15), presença de fatores de risco identificados (p = 0,17), presença de convulsões (p = 0,31), outras complicações clínicas (p = 0,11) e mortalidade (p = 0,66) não diferiram entre os grupos. Anormalidades sensoriais (p <0,0001) e presença de cefaléia (p = 0,003) foram mais prevalentes em pacientes com meningite. Como esperado, a contagem de leucócitos, glicose e proteína no LCR foram significativamente diferentes entre pacientes com meningite e pacientes sem meningite. As concentrações de sTREM-1 no LCR de pacientes com meningite bacteriana foi superior quando comparada com pacientes com meningite viral e com controles (1204,67 pg/ml, 39,34 pg/ml e 12,09 pg/ml, respectivamente; p <0,0001). Quando sTREM-1 foi usado como um determinante de diferenciação entre pacientes com ou sem meningite bacteriana, a análise da área sob a curva ROC foi de 0,95 (IC de 95% = 0,89-1,00; p <0,0001). A presença de fatores de risco para a meningite bacteriana (p = 0,04), anormalidades sensoriais (p <0,0001), contagem de leucócitos no LCR (p = 0,01), níveis de glicose no LCR (p = 0,002), níveis de proteína no LCR (p = 0,032) e os níveis de sTREM-1 no LCR (p = 0,004) foram associados com meningite bacteriana, incluindo os níveis sTREM-1 acima do ponto de corte estabelecido de 68,0 pg/ml (p <0,0001). A meningite bacteriana (p = 0,02) e os valores de sTREM-1 maior do que o ponto de corte (68,0 pg/ml) (p = 0,04) foram associados com sequelas neurológicas graves e morte neste grupo de pacientes. Conclusão: Avaliamos os níveis sTREM-1 de crianças com suspeita clínica de meningite. Os níveis de s-TREM-1 foram aumentados nos casos de meningite bacteriana e correlacionados com o prognóstico. Os nossos resultados sugerem que níveis elevados de sTREM-1 no LCR podem ser utilizados como um biomarcador para o diagnóstico de meningite bacteriana aguda em crianças e que pode ser útil na determinação do prognóstico do paciente nesse cenário. / Background: Bacterial meningitis is an important cause of morbidity and mortality in infancy. Cerebrospinal fluid (CSF) analysis remains the gold standard diagnostic tool, however new biomarkers for diagnosis and prognosis are still required. Triggering receptor expressed on myeloid cells-1 (TREM-1) is a transmembrane receptor expressed on neutrophils and monocytes that plays an important role on the immune response. Its soluble fraction (sTREM-1) is also increased in infection, inflammation or immune diseases. In this study we evaluate the value of sTREM-1 as a biomarker of acute bacterial meningitis in pediatric patients and its possible use as a prognostic tool prospectively. Methods: Sixty-one pediatric patients, from 0 to 10 years of age were evaluated for meningitis and were prospectively included in this study. At admission, following clinical hypothesis of meningitis patients were submitted to CSF analysis for diagnosis and a sample of initial CSF was also used for TREM-1 analysis. Patients were followed during hospitalization and clinical evaluation and treatment outcome were recorded for posterior analysis. Results: Thirty-eight (62%) out of 61 patients were negative for meningitis, 7 (11%) patients were diagnosed with viral meningitis and 16 (27%) patients were diagnosed with and received treatment for acute bacterial meningitis. Sex (p = 0.15), presence of identified risk factors (p = 0.17), presence of seizures (p = 0.31), other clinical complications (p = 0.11), and mortality (p = 0.66) did not differ among groups. Sensorial abnormalities (p<0.0001) and presence of headache (p= 0.003) were more prevalent in patients with meningitis. As expected, leukocyte count, glucose, and protein levels were significantly different between patients with meningitis and patients without meningitis. Concentrations of sTREM-1 in CSF from patients with bacterial meningitis was higher when compared to patients with viral meningitis and with controls (1204.67 pg/ml, 39.34 pg/ml and 12.09 pg/ml, respectively; p<0.0001). When sTREM-1 was used as a determinant to differentiate between patients with or without bacterial meningitis, the analysis of the area under the ROC curve (AUC) was 0.95 (95% CI=0.89-1.00; p<0.0001). Presence of risk factors for bacterial meningitis (p = 0.04), sensorial abnormalities (p<0.0001), CSF leukocyte count (p = 0.01), CSF glucose levels (p = 0.002), CSF protein levels (p = 0.032) and CSF sTREM-1 levels (p = 0.004) were all associated with bacterial meningitis, including sTREM-1 levels above the established cut-off point of 68.0 pg/ml (p<0.0001). Bacterial meningitis (p = 0.02) and values of sTREM-1 higher than the cut-off point (68.0 pg/ml) (p = 0.04) were associated with death and severe neurological disabilities in this patient cohort. Conclusion: We evaluated sTREM-1 levels in CSF of children with clinical hypothesis of meningitis. The sTREM-1 levels were increased in bacterial meningitis and correlated with prognosis. Our results suggest that CSF sTREM- 1 levels can be used as a biomarker for diagnosis of acute bacterial meningitis in children and it might be useful in determining patient’s prognosis in this scenario.