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2016
Scheid Filho, R, Eckhard D, Gonçalves da Silva GR, Campestrini L.  2016.  Application of Virtual Reference Feedback Tuning to a non-minimum phase pilot plant, Sept. 2016 IEEE Conference on Control Applications (CCA). :1318–1323., Buenos Aires: IEEE Abstract

Virtual Reference Feedback Tuning (VRFT) is a data-driven technique used to design controllers without the need of a process model, only input-output data is utilized. When the process has non-minimum phase (NMP) zeros, the original method usually presents poor performance, because scarcely the reference model has the same NMP zeros as the process. To overcome this problem, a flexible criterion has been proposed to the VRFT method, in a way that both the controller parameters and the NMP zeros of the process are estimated together. In this paper we present the application of the VRFT method with flexible criterion to the level control of a MIMO pilot plant. We show that a sequential controller design may incorporate NMP behavior to the process. We then use the VRFT method with flexible criterion to design the controller using only closed-loop data from the process.

Salton, AT, Eckhard D, Flores JV, Fernandes G, Azevedo G.  2016.  Disturbance observer and nonlinear damping control for fast tracking quadrotor vehicles, Sept. 2016 IEEE Conference on Control Applications (CCA). :705–710., Buenos Aires: IEEE Abstract

This paper considers the design and implementation of a discrete-time fast tracking controller for quadrotor vehicles subject to perturbations. The proposed controller consists of a model-based disturbance observer and a Composite Nonlinear Feedback (CNF) controller. The CNF control law introduces nonlinear damping to the system so that it possesses a fast rise time without overshoot. The least square identification method is applied to develop a model based disturbance observer, thus decoupling the problems of track following and disturbance rejection. Experimental results are provided in order to validate the proposed approach.

Flores, JV, Eckhard D, Salton AT.  2016.  Modified {MIMO} Resonant Controller Robust to Period Variation and Parametric Uncertainty, Sept. 2016 {IEEE} Conference on Control Applications ({CCA}). :1256–1261., Buenos Aires: IEEE Abstract

In this work a modified Resonant Controller is proposed to deal with the tracking/rejection problem of periodic signals robust to period variations and parametric uncertainties in the plant. The control strategy is based on a resonant structure in series with a notch filter, which will be responsible to improve the robustness to period variation. A robust state feedback controller is designed by solving a linear matrix inequality (LMI) optimization problem guaranteeing the robust stability of the closed loop system. A numerical example is presented to illustrate the method.

Bruscato, LT, de Freitas EP, Heimfarth T, de Araujo JP.  2016.  Self-correcting time synchronization in wireless sensor networks using low-power devices, Oct. IECON 2016 - 42nd Annual Conference of the IEEE Industrial Electronics Society. :4820-4825. Abstract
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Haas, AN, Silva-Boghossian CM, Colombo AP, Albandar J, Oppermann RV, Rosing CK, Susin C.  2016.  Predictors of clinical outcomes after periodontal treatment of aggressive periodontitis: 12-month randomized trial, May 20. Braz Oral Res. 30, Number 1 AbstractWebsite

Little is known about the factors that may be used in clinical practice to predict the therapeutic response of aggressive periodontitis patients. The aim of this study was to determine predictors of clinical outcomes after non-surgical treatment of aggressive periodontitis. A total of 24 patients (aged 13-26 years) received oral hygiene instructions, as well as subgingival scaling and root planing. Twelve subjects received systemic azithromycin at random. Clinical variables were assessed at baseline, 3, 6, 9, and 12 months. Baseline microbiological assessment was performed by checkerboard DNA-DNA hybridization. Multivariable models used generalized estimating equations. There were significant improvements in the entire sample in regard to pocket depth, clinical attachment level and bleeding on probing. Significant predictors of a reduction in mean pocket depth were: use of azithromycin, non-molar teeth, generalized disease and baseline pocket depth. Absence of plaque predicted a 0.22 mm higher attachment gain, whereas a baseline pocket depth >/=7 mm predicted a 1.36 mm higher attachment loss. Azithromycin, plaque, and baseline pocket depth were significant predictors of bleeding on probing. The concomitant presence of all three red complex species predicted a 0.78 mm higher attachment loss. It may be concluded that dental plaque, tooth type, disease extent, baseline pocket depth, and use of azithromycin were significant predictors of the clinical response to treatment for aggressive periodontitis in young individuals. Moreover, the presence of multiple periodontal pathogens may predict challenges in achieving a favorable outcome for aggressive periodontitis.

Heimfarth, T, Giacomin JC, d. Araujo JP, d. Freitas EP.  2016.  A Preamble Ahead Anycast Protocol for WSNs, March. 2016 IEEE 30th International Conference on Advanced Information Networking and Applications (AINA). :458-466. Abstract
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Tesch, D, Eckhard D, Bazanella AS.  2016.  Iterative feedback tuning for cascade systems, June. 2016 European Control Conference (ECC). :495–500., Aalborg Abstract

Iterative Feedback Tuning (IFT) is a data-driven method used to tune parameters of feedback controllers minimising an H2 criterion. The method uses data from experiments to estimate the gradient of the criterion, and uses iterative quasinewton algorithms to adjust the controllers. When the method is used in cascade systems, usually the inner loop is firstly adjusted, and after the outer loop. In this article we describe an extension to the IFT method that adjusts both inner and outer loop at the same time using only data from closed-loop experiments at each iteration.

Marinho, MAM, da Costa JPCL, Antreich F, de Almeida ALF, Galdo DG, de Freitas EP, Vinel A.  2016.  Array interpolation based on multivariate adaptive regression splines, July. 2016 IEEE Sensor Array and Multichannel Signal Processing Workshop (SAM). :1-5. Abstract
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de Nunes, HS, Schramm R, Jung CR, Coelho LW.  2016.  Automated Sight-singing Assessment Tool, July. 14th International Conference on Music Perception and Cognition. :529-533., San Francisco Abstract
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Kampits, C, Montenegro MM, Ribeiro IW, Furtado MV, Polanczyk CA, Rosing CK, Haas AN.  2016.  Periodontal disease and inflammatory blood cytokines in patients with stable coronary artery disease, Jul-Aug. J Appl Oral Sci. 24:352-8., Number 4 AbstractWebsite

MATERIAL AND METHODS: This cross-sectional study included 91 patients with stable CAD who had been under optimized cardiovascular care. Blood levels of IL-1beta, IL-6, IL-8, IL-10, IFN-gamma, and TNF-alpha were measured by Luminex technology. A full-mouth periodontal examination was conducted to record probing depth (PD) and clinical attachment (CA) loss. Multiple linear regression models, adjusting for gender, body mass index, oral hypoglycemic drugs, smoking, and occurre:nce of acute myocardial infarction were applied. RESULTS: CAD patients that experienced major events had higher concentrations of IFN-gamma (median: 5.05 pg/mL vs. 3.01 pg/mL; p=0.01), IL-10 (median: 2.33 pg/mL vs. 1.01 pg/mL; p=0.03), and TNF-alpha (median: 9.17 pg/mL vs. 7.47 pg/mL; p=0.02). Higher numbers of teeth with at least 6 mm of CA loss (R2=0.07) and PD (R2=0.06) were significantly associated with higher IFN-gamma log concentrations. Mean CA loss (R2=0.05) and PD (R2=0.06) were significantly related to IL-10 concentrations. Elevated concentrations of TNF-alpha were associated with higher mean CA loss (R2=0.07). CONCLUSION: Periodontal disease is associated with increased systemic inflammation in stable cardiovascular patients. These findings provide additional evidence supporting the idea that periodontal disease can be a prognostic factor in cardiovascular patients.

Gaio, EJ, Haas AN, Rosing CK, Oppermann RV, Albandar JM, Susin C.  2016.  Effect of obesity on periodontal attachment loss progression: a 5-year population-based prospective study, Jul. J Clin Periodontol. 43:557-65., Number 7 AbstractWebsite

AIM: The aim of this study was to assess the effect of overweight and obesity on periodontal attachment loss (PAL) progression in an urban population from south Brazil. METHODS: In 2001, a population-based oral health survey entitled "Epidemiology of periodontal diseases: the Porto Alegre Study" was conducted by drawing a probabilistic sample of 1586 individuals. After 5 years, 755 (participation rate: 47.6%) individuals were re-examined. For this analysis, self-reported diabetics, underweight individuals, and individuals with <6 teeth were excluded. Poisson regressions were used to calculate relative risks (RR) and 95% confidence intervals (CI) adjusted for sex, age, skin colour, education, socio-economic status, smoking and dental care. RESULTS: Five hundred and eighty-two individuals (333 males/249 females, 36.02 +/- 14.97 years) were included. Overall, obese individuals had significantly higher risk of experiencing PAL progression than individuals with normal weight after adjusting for important co-factors (RR = 1.36, 95% CI = 1.04-1.78). In a stratified analysis, no statistically significant associations were observed between PAL progression and obesity for males (RR = 1.13, 95% CI = 0.75-1.69), whereas obese females were at statistically significant higher risk than normal weight females (RR = 1.64, 95% CI = 1.11-2.43). CONCLUSION: Obesity appears to be a risk factor for PAL progression for females but not males in this developing country population.

do Ritter, MN, Francischini H, Kuhn LA, da Luz NC, Michels FH, de Morais ALM, Paim PAV, Xavier PLA, de Francesco CG.  2016.  El sesgo del operador en la replicabilidad de los estudios tafonómicos comparativos, jan. Revista Brasileira de Paleontologia. 19:449–464., Number 3: Sociedade Brasileira de Paleontologia AbstractWebsite

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Haas, AN, Wagner TP, Muniz F, Fiorini T, Cavagni J, Celeste RK.  2016.  Essential oils-containing mouthwashes for gingivitis and plaque: Meta-analyses and meta-regression, Dec. J Dent. 55:7-15. AbstractWebsite

OBJECTIVES: To evaluate the efficacy of EO as adjuncts to mechanical plaque control (MPC) on the reduction of plaque and gingivitis when compared to placebo or cetylpyridium chloride (CPC). DATA: Randomized controlled trials of at least 6 months of follow-up including systemically healthy individuals with gingivitis were included. SOURCES: MEDLINE, EMBASE, Lilacs and SCOPUS were searched up to April 2016. From 3045 citations, 16 studies were included. 14 studies assessed the Quigley-Hein Plaque Index (QHI) and 11 studies assessed the Modified Gingival Index (MGI) and were included in meta-analyses and meta-regression. STUDY SELECTION: The analysis of risk of bias suggested that the quality of the studies ranged from moderate to low. Mean QHI (WMD=-0.86, 95%CI -1.05 to -0.66) and MGI (WMD=-0.52, 95%CI -0.67 to -0.37) were lower for EO+MPC than placebo+MPC. Reductions in plaque and gingivitis were, respectively, 32% and 24% larger for EO+MPC than placebo+MPC. The decreases in QHI (WMD=-0.95, 95%CI -1.26 to -0.63) and in MGI (WMD=-0.34, 95%CI -0.53 to -0.15) observed in the EO+MPC group, compared to placebo+MPC in interproximal areas, were significantly different and in favor to EO+MPC. EO+MPC compared to CPC+MPC resulted in clinically lower levels of plaque and gingivitis. High heterogeneity (I(2)>95%) was found and explained (MGI-R(2)=63.6%; QHI-R(2)=80.1%) by differences between studies in the percentage of males, supervision of the mouthwashes and provision of oral hygiene. CONCLUSIONS: EO seems to be superior to placebo+MPC and CPC+MPC for reduction of plaque and gingival inflammation in patients with gingivitis. Expected benefits may be clinically relevant and may also reach the interproximal area. CLINICAL SIGNIFICANCE: Mouthwashes containing essential oils should be considered the first choice for daily use as adjuvants to self-performed mechanical plaque control.

Mendez, M, Haas AN, Rados PV, Sant'ana FM, Carrard VC.  2016.  Agreement between clinical and histopathologic diagnoses and completeness of oral biopsy forms, Aug 22. Braz Oral Res. 30:e94., Number 1 AbstractWebsite

The present study aimed to assess the rate of agreement between clinical and histopathological diagnoses and to report the frequency of completed forms for specimens that were subjected to histopathological examination and retrospectively examined. Data from 8,168 specimens submitted to histopathological examination were retrieved from the records. A total of 5,368 cases were included. Agreement was defined based on the definition of lesion nature according to its diagnostic category. Sensitivity, specificity, and positive and negative predictive values were calculated for each diagnostic category. The highest rate of agreement was observed for periapical lesions (92.6%), followed by potentially malignant disorders (90.1%) and non-neoplastic proliferative disorders (89.3%). Low rates of histopathological confirmation of the clinical impression were observed for mesenchymal tumors (25.0%) and cysts (44.2%). Sensitivity values were > 0.70 for all lesions, except for cysts (0.51). Specificity was relatively high, ranging from 0.97 to 1.00. The frequency of incomplete biopsy forms ranged from 16.8% (malignant tumors of oral mucosal epithelium) to 51.0% (nonspecific inflammatory reaction). The most frequently completed biopsy forms corresponded to epithelial malignant tumors (83.2%) and glandular inflammation (72.3%). In conclusion, there was an acceptable level of agreement. The low level of completeness of biopsy forms indicates little awareness about the relevance of gathering detailed information during clinical examination.

Milanesi, FC, Kauer B, Wagner TP, Daudt LD, Haas AN.  2016.  Self-reported halitosis and associated demographic and behavioral factors, Aug 22. Braz Oral Res. 30:e71., Number 1 AbstractWebsite

Halitosis is still poorly studied in young adults. The aim of this study was to evaluate the occurrence of self-reported halitosis and associate it with demographic and behavioral factors in young adult dental students. This cross-sectional study was designed as a census of students enrolled in three initial and three final semesters of a dental course in a Brazilian public university. Of 284 eligible students, 257 (90.5%) completed a self-administered questionnaire. Self-reported halitosis was the primary study outcome, and was assessed with the question "do you feel you have bad breath?". Data on age, gender, frequency of tooth brushing and interproximal cleaning, tongue cleaning, mouth rinse use and dry mouth were collected using the questionnaire, and were considered independent variables. Of the students surveyed, 26.5% reported as never, 51.7% as rarely, 21.4% as sometimes, and 0.4% as always feeling they had halitosis. Morning halitosis was reported by 90.6% of those who reported halitosis. In the final multiple model, last semester students had a 55% lower chance of reporting halitosis, compared with students from the first semesters [odds ratio (OR) 0.46; 95%CI 0.24-0.89]. Women had a 2.57fold higher chance of reporting halitosis (OR = 2.57; 95%CI 1.12-5.93). Dry mouth increased the chance of self-reported halitosis 3.95-fold, compared with absence of dry mouth (OR = 3.95; 95%CI 2.03-7.68). It can be concluded that self-reports of halitosis were low among dental students, but may represent an important complaint. Gender, dry mouth and level of college education of the dentist were factors significantly associated with self-reported halitosis.

Wagner, TP, Costa RS, Rios FS, Moura MS, Maltz M, Jardim JJ, Haas AN.  2016.  Gingival recession and oral health-related quality of life: a population-based cross-sectional study in Brazil, Aug. Community Dent Oral Epidemiol. 44:390-9., Number 4 AbstractWebsite

OBJECTIVES: To assess the association between gingival recession (GR) and oral health-related quality of life (OHRQoL) in a Brazilian population of adults. METHODS: A representative sample from Porto Alegre city was drawn in 2011 using a multistage probability sampling strategy. For this study, 740 individuals, 35-59 years of age and with >/=6 teeth, were included. GR was assessed by two calibrated examiners at four sites in all present teeth. The Oral Health Impact Profile (OHIP-14) was used to assess OHRQoL. OHIP-14 was dichotomized using 'fairly often' as the cutoff point for a negative impact. Multiple logistic regression models were fitted to define which descriptors of GR were associated with the dichotomous outcome of OHIP-14, including dentine hypersensitivity in separate models, adjusting for age, gender, socioeconomic status, smoking, dental care, and missing teeth. RESULTS: Mean OHIP was significantly higher for individuals with >/=1 tooth with GR >/=2, >/=3, >/=4, and >/=5 mm. Individuals with >/=1 tooth with GR >/=2 mm had approximately two times higher chance of having a negative impact than individuals without GR of this threshold [odds ratio (OR) = 1.99, 95% confidence interval (CI) 1.05-3.78]. When buccal and proximal sites were analyzed separately, the presence of GR was significantly associated with worst quality of life only in anterior and not in posterior teeth. GR in the lower arch had no impact on OHRQoL. GR >/=2 mm affected only physical pain (OR = 2.61; 95% CI 1.06-6.42), whereas GR >/=4 mm affected functional limitation, physical pain, psychological discomfort, physical and psychological disabilities, with ORs ranging from 1.43 to 1.91. Dentine hypersensitivity alone was not associated with OHRQoL, but it modified the association between GR and OHIP when present concomitantly with GR, mainly in buccal sites. CONCLUSIONS: OHRQoL is poorer in this adult population in the presence of GR, mainly in upper and anterior teeth. Dentine hypersensitivity and esthetics were found to be factors linking GR to OHRQoL.

do Ritter, MN, Erthal F.  2016.  Time-averaging e suas implicações para o registro fóssil marinho, aug. Terrae Didatica. 12:81., Number 2: Universidade Estadual de Campinas AbstractWebsite
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Orfanus, D, de Freitas EP, Eliassen F.  2016.  Self-Organization as a Supporting Paradigm for Military UAV Relay Networks, April. IEEE Communications Letters. 20:804-807., Number 4 Abstract
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Zanella, SM, Pereira SS, Barbisan JN, Vieira L, Saba-Chujfi E, Haas AN, Rosing CK.  2016.  Periodontal disease, tooth loss and coronary heart disease assessed by coronary angiography: a cross-sectional observational study, Apr. J Periodontal Res. 51:221-7., Number 2 AbstractWebsite

OBJECTIVE AND BACKGROUND: To evaluate the association between periodontal disease, tooth loss and coronary heart disease (CHD). There is still controversy about the relationship between periodontal disease and tooth loss with vessel obstruction assessed using coronary angiography. MATERIAL AND METHODS: This cross-sectional study included 195 patients that underwent coronary angiography and presented with at least six teeth. Patients were classified into three categories of coronary obstruction severity: absence; one or more vessels with /= 50% obstruction. The extent of coronary obstruction was dichotomized into 0 and >/= 1 affected vessels. A periodontist blinded to patient CHD status conducted a full mouth examination to determine mean clinical attachment loss, mean periodontal probing depth and tooth loss. Multiple logistic regression models were applied adjusting for age, gender, hypertension, smoking, body mass index, low-density lipoprotein cholesterol and C-reactive protein. RESULTS: Most patients were males (62.1%) older than 60 years (50.8%), and 61% of them had CHD. Mean periodontal probing depth, clinical attachment loss and tooth loss were 2.64 +/- 0.72 mm, 4.40 +/- 1.31 mm and 12.50 +/- 6.98 teeth respectively. In the multivariable models, tooth loss was significantly associated with a higher chance of having at least one obstructed vessel (odds ratio = 1.04; 95% confidence interval 1.01-1.09) and with vessel obstruction >/= 50% (odds ratio = 1.06; 95% confidence interval 1.01-1.11). No significant associations were found between periodontal variables and vessel obstruction. CONCLUSION: Tooth loss was found to be a risk indicator for CHD.

Brendler, CF, Teixeira FG.  2016.  Método para obtenção de medidas antropométricas utilizando um digitalizador 3D de baixo custo, 2016. Design e Tecnologia. 6(11):53-67. AbstractFull Text

The aim is to develop a method for obtaining anthropometric parameters using a low cost three-dimensional digitizer. The research methodology is divided in five steps: literature review; collection and analysis of anthropometric data using the direct method and also the development of the indirect method for obtaining anthropometric measurements; comparison and data analysis; discussion of results and the completion of the research. The digitization process developed it is based on Microsoft Kinect, a low-cost device, and also on the software kscan3D. For the anthropometric collection from the three-dimensional model is used Autodesk 3D Studio Max. This research presents requirements and constraints for generate the three-dimensional model in order to obtain a mesh with satisfactory precision. It is presented a flowchart to guide the implementation of the developed method in the design process as well as a summary table containing guidelines for this application. The developed method achieved 97.96% of compatibility considering the results of the measured variables in relation to the direct method. These results were obtained with an exposure time of the individual of only 3 minutes and 28 seconds, which is less than the time required in the direct method – 1 hour and 12 minutes. This demonstrates one major contribution of the developed method.

Teixeira, FG.  2016.  Perspectivas axonométricas e vistas principais no ensino de geometria descritiva, 2016. Revista Educação Gráfica. 20:289-302. AbstractFull Text

This work present axonometric and orthographic views to learning of Descriptive Geometry concepts. Axonometric views are a good way to show the utility of successive auxiliary views because they present the process and promote the 3D comprehension of objects. The paper proposes ways to build axonometric projections from any point of view by Descriptive Geometry tools. Besides, the use of the principal views enhances the understanding of successive auxiliary views, but in a more complex context where the student must choose directions to find the correct projections. Through these directions, you can choose the sequence of auxiliary planes that result in orthographic views. This work shows how two unusual concepts in the Descriptive Geometry education context can promote a better understanding of many of its contents.

Brendler, CF, Teixeira FG, da Silva FP, Müller MS.  2016.  Uso da digitalização 3D do corpo humano para desenvolvimento de produtos personalizados: Análise comparativa entre os scanners Artec EVA e o Kinect, 2016. Estudos em Design (Online). 24:41-60. AbstractFull Text

The aim of this paper is comparing both tridimensional scanners: white light Artec Eva; and Infra-red light Microsoft Kinect. This comparison enables evaluate possibilities of these equipments for developing user-centered product projects. It was carried out comparison's concerning both precision and dimensional deviation through virtual and physical models generated by CAD and CAM systems. It was verified the need of eliminating the human body movement by using physical models in the performed analysis. As a result, both scanners demonstrated measurement precision, with the advantage of Artec Eva over Microsoft Kinect. The selection of the most appropriated scanner concerning the projects needs evolves factors such as: the available cost for the project; and the required precision fidelity for the aimed product. Both digital scanners considered in this paper contribute to the development of customized products, showing the relationships between tools and needed product fidelity.

Brendler, CF, Teixeira FG, Kindlein W, Pohlmann M, Rossi W.  2016.  FABRICAÇÃO DIGITAL PARA AUXILIAR NO ENSINO-APRENDIZADO DE ALUNOS COM DEFICIÊNCIA VISUAL: ESTUDO DE CASO DOS SISTEMAS NANOESTRUTURADOS, 06 de outubro. 12º Congresso Brasileiro de Pesquisa e Desenvolvimento em DesignBlucher Design Proceedings. 12:2389-., Belo Horizonte Abstract

Dados obtidos com o Censo Demográfico, em 2010, revelaram que quase 24% da população brasileira possuem algum tipo de deficiência, sendo a deficiência visual a de maior ocorrência. Dentre as políticas sociais que buscam atender às diferentes necessidades dos cidadãos, vale destacar o direito universal à educação. Recursos didáticos de diferentes naturezas vêm sendo empregados como ferramenta para auxiliar o ensino-aprendizagem de pessoas com deficiência visual. Vale, porém, questionar se esses recursos são realmente eficazes na compreensão de determinados conteúdos? Assim, o presente trabalho propõe a validação de modelos didáticos 3D para permitir a compreensão de sistemas nanoestruturados por deficientes visuais. A avaliação dos modelos foi realizada por usuário cego e, para tanto, foi utilizada uma adaptação do instrumento SETT (Alunos, Ambiente, Tarefas e Ferramentas). Os resultados indicam que os modelos produzidos por impressão 3D necessitam de revisão no que tange à legenda em Braille, mas, quanto aos demais aspectos, são viáveis para o uso como recurso didático para alunos com deficiência visual.

Teixeira, FG.  2016.  UM MODELO EVOLUTIVO PARA O PROCESSO DE GERAÇÃO E SELEÇÃO DE ALTERNATIVAS EM DESIGN, 06 de outubro. 12º Congresso Brasileiro de Pesquisa e Desenvolvimento em DesignBlucher Design Proceedings. 12:4374-., Belo HorizonteSão Paulo: Editora Blucher Abstract

The conceptual design step is the most complex of the design process and brings great challenges to designers. The number of possible concepts from a combination of functional principles can reach millions. This could derail an exhaustive search for the best possible concepts. So, this work proposes an evolutionary approach to that problem. The result is a framework based on a Genetic Algorithm (GA) that combines the specific properties of the design process with the core of GA, improving this process as a natural evolution.

Pires, CC, Laureano JV, Gnoatto S,; Barreto F, De Araújo BV, Dalla Costa T, Tasso L, Grünspan LD.  2016.   Development and validation of a sensitive and selective LC-MS/MS method for the determination of an antimalarial drug candidate in rat plasma, and its application to a preclinical pharmacokinetic study. Acta Chromatographica.