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Melanoma is considered one of the most aggressive types of cancer due to its high propensy for metastasis, which significantly reduces survival chances when detected late. Moreover, melanoma exhibits strong immunogenic characteristics, complicating its treatment, increasing the need to develop more effective techniques of therapy. In the field of oncology, mathematical modeling enables the analysis and distinction of the various mechanisms involved in tumor progression. This allows the analysis of numer- ous scenarios, which would be impractical experimentally. The main objective of this study is to develop a mathematical model that describes melanoma dynamics in the presence of Tumor-Associated Macrophages (TAM) and Chimeric Antigen Receptor (CAR) T-cell immunotherapy. The goal is to assess why this therapy often falls short in erradicating solid tumors like melanoma and to understand the role of TAM in this failure. This research encompasses stability analysis of the equilibrium points of the model, sensitivity analysis of its parameters, and the examination of numerical solutions. Our results showed that immunosuppression caused by TAM has a negative impact on the effectiveness of the dose and varying the cytotoxicity of CAR T-cells together with dose. Adjusting CAR T-cell cytotoxicity and treatment dosage may enhance tumor control, with the initial tumor burden playing a crucial role in treatment effectiveness.

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sensitivity and uncertainty analysis hold significant importance across a range of applications, spanning from industrial problems to climate change, financial risk assessment, as well as mathematical and computational models. These analyses involve identifying influential input parameters in models to comprehend their impact on the output. Sensitivity analysis can be performed locally, examining parameter effects at a fixed value, or globally, evaluating the model across a range of parameter values. The Sobol method stands as a robust approach for global sensitivity analysis, employing a Sobol sequence to create samples more uniformly within the input parameter space, thus enabling efficient exploration of model inputs. This paper aims to introduce a computational implementation in Scilab to generate the Sobol sequence for utilization in sensitivity analysis through the Sobol method. A test case was applied to generate Sobol sequences and discuss the obtained results.

Copyright of PARC Pesquisa em Arquitetura e Construção is the property of Universidade Estadual de Campinas - Portal de Periodicos Eletronicos Cientificos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT An experiment was conducted to evaluate the effect of the intake of a mixture of fish and sacha inchi oils (iOM), organic selenium (iSe), and organic chromium (iCr) on egg production (EP) and feed conversion ratio (FCR) of Isa Brown second-cycle laying hens (SCLH) for 16 weeks (91-106 weeks old). Egg production and FCR were evaluated using multivariate models that included conventional equations and artificial neural networks (ANN) to study multiple nutritional interactions as alternatives to univariate dose-response models. Based on the best models, iOM, iSe, and iCr levels were optimized, and a global sensitivity analysis was implemented to quantify their influence on EP and FCR. The modified logistic model was selected as the best strategy to represent EP. In the case of FCR, an ANN model with a feed-forward architecture and softmax transfer function was selected as the best alternative. One of the scenarios to simultaneously optimize EP (89.1%) and FCR (1.94 kg feed/kg egg) at 16 weeks of production was established with 3.3 g/hen·day of iOM, 0.132 mg/ hen·day of iSe, and 0.176 mg/hen·day of iCr. However, optimization considering only FCR results in much lower optimal iCr levels (between 0.083 and 0.105 mg/hen·day) with a slight decrease in EP (87.9%). The global sensitivity analysis showed that iSe is an essential factor associated with the increase in EP, and iCr is the most influential factor for the decrease in FCR. When both criteria were taken into account simultaneously from a desirability function, iSe was the most critical factor.

Copyright of JBES: Brazilian Journal of Health Economics / Jornal Brasileiro de Economia da Saúde is the property of JBES: Brazilian Journal of Health Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The hydrological models are important tools to evaluate the hydrological behavior of watersheds, helping in the decision making. Thus, this study had the objective of evaluating the performance of the Soil and Water Assessment Tool (SWAT) model in the flow simulation in the Ribeirão Taquaruçu Hydrographic Basin. Flow data from two fluviometric stations were used from April 2013 to August 2015. The results of the sensitivity analysis indicated that the most influential parameters are the SOL_K (saturated hydraulic conductivity of the soil) and CN2 (curve number for the condition II). The Nash-Sutcliffe (NSE) objective functions and the determination coefficient (R2) indicated, in the calibration period, the following values: -0.05 and 0.55 (sub-basin 1); 0.51 (sub-basin 3), respectively. In the validation period, the following results were presented for NSE and R2: 0.44 and 0.54 (sub-basin 1); 0.24 and 0.29 (sub-basin 3), in that order. Considering that the object of study is responsible for a large part of the water supply of Palmas - TO and that the program was unable to simulate the minimum flows adequately, the results are considered unsatisfactory.

Measurement and evaluation of soil erosion and consequent sediment yield are fundamental in the planning and management of watersheds, as they allow the identification of critical areas susceptible to erosive processes. This study analyzed the sediment yield generated by water erosion in the Indaia River Basin, Alto São Francisco, Minas Gerais, by using the SWAT hydrological model. From a regional/local scale, the initial simulation of the variables (flow and solid discharge) was performed on a monthly scale from 1988 to 2017. Then, parameter-sensitivity analysis, calibration, and validation of the model were executed. In the monthly calibration (1988 to 2007), the performance of the simulations for flow was R2=0.92 and NSE=0.91 and for total solid discharge R2=0.51 and NSE=0.50. In the monthly validation (2008 to 2017) for flow, R2=0.85 and NSE=0.82 was obtained and for total solid discharge R2=0.19 and NSE=0.16. Despite the unsatisfactory result in the validation stage, the model was able to analyze the distribution of sediment production by sub-basins or even by the Hydrologic Response Unit (HRU). Therefore, a sediment-yield map was generated which qualitatively indicated a tendency for greater erosive processes in the central portion of the basin. The results will support public policies mitigating environmental degradation of the Indaia River Basin.

This teaching case enables students from undergraduate courses in Business Administration, Accounting Sciences, and Production Engineering to apply functions available in MS-Excel® to assist in the analysis of the economic-financial feasibility of an investment project. The case must be used as supplementary teaching material in the undergraduate courses of Economic Engineering, Economic Evaluation of Projects, Evaluation of Investment Projects, or similar disciplines. Students are required to have knowledge of financial mathematics, probability, and statistics and to know the basics of MS-Excel®. The case study concerns a public-private partnership of a prison. The analyzes were performed mostly based on hypothetical data, however, data from the Ribeirão das Neves Prison, in Minas Gerais, Brazil, were also used. The private partner believes that the political risk is imminent, impacting the enterprise’s minimum rate of attractiveness (MRA/TMA), and does not give up earning 10% per year above the TMA, whatever that rate. By simulating the net present value of the business and the Z~N(0.1) statistic, it was possible to calculate the probability of the enterprise registering a surplus equal to or greater than 1.5 times the cost of the investment, given the assumptions adopted. [ABSTRACT FROM AUTHOR]

Purpose: Evaluate the sensitivity and economic viability of the feedlot system used for fattening cattle using reference a property located in the northern region of the state of São Paulo, Brazil. Methodology: We used a multidimensional approach to evaluate the sensitivity. The economic result was analyzed through cash flow, the net present value (NPV) being the viability indicator. The risks were incorporated with the Monte Carlo simulation for the prices of feed, purchase and sale of animals that were the discrete random variables, the value measure was the NPV, calculated with the minimum attractiveness rate of 7,55% per semester and the probabilities were estimated by relative frequency. Results: The probability of feedlot being an economically attractive activity was 30,2%, consequently the system was not viable in 69,8%. In the context of sensitivity, the feedlot was more vulnerable to fluctuations in the sale price, the 1% increase in the price fed cattle of generates on increased of 46% in NPV, being followed by feeder cattle price, the 1% increase in the feeder cattle price leads to a 29% reduced in NPV, and by the feeding price, the 1% increase in the feeding price leads to a 12% decreased in NPV. Contributions of the study: The results found in this research may support new evaluations in representative samples, incorporate the studies on this topic and assist decision makers. [ABSTRACT FROM AUTHOR]

Electrorresistive profiling of moisture inside a quartz sand bed on a pilot-scale vibrating screen was treated here. As electrode or probe configuration for resistivity measurement is concerned, the classical Wenner a array was used, requiring equal electrode spacing, and correct penetration depth and alignment. Here, the influence of small variations in penetration depth and lack of probe collinearity on the moisture readings, using a digital earth resistance tester and copper wires as probes, was evaluated. The penetration depths studied were 50 mm and 55 mm. In turn, the electrode misalignment tested was 10 mm. The only factor that has caused statistically significant effect in measurements was probe penetration depth, at least under the range tested here. [ABSTRACT FROM AUTHOR]

ABSTRACT Traditional methods of economic evaluation of wood and charcoal production projects are based on indicators analysis, however, they are subject to market variations and uncertainties. The study was carried out in the city of Lamim, Minas Gerais State, to evaluate the economic viability of wood and charcoal production using the kiln-furnace system, due to the need to know the economic viability of this new production system. Sensitivity analysis using the Monte Carlo technique was performed on costs and revenues. The wood and charcoal production cash flow was elaborated and the following criteria were used in the economic analysis: Net Present Value (NPV), Benefit-Cost Ratio (BCR), Equivalent Periodic Value (EPV), and Internal Return Rate (IRR). The wood and charcoal production sensitivity analysis was carried out using the software @RISK, according to the VPE parameter, which allows comparing projects with different durations. Wood production was economically viable, with NPV of $40.26 ha-1 and EPV of $ 16.80 ha-1, with an average production cost of $13.51 m3 wood-1. The EPV mean value found in the sensitivity analysis was $18.33 ha-1. The charcoal production was economically viable, with NPV of $4.43 mdc charcoal-1 and EPV of $3.52 mdc charcoal-1. The EPV mean value found in the sensitivity analysis was $9.80 mdc charcoal-1. It was possible to conclude that the wood and charcoal production are economically viable in the region.

The present study proposes a method for the execution of uncertainty and sensitivity analysis on TRANSURANUS code, adapted for the use of stainless steel AISI-348 as the cladding material for a PWR reactor fuel rod, thus allowing to determine which input data are more relevant to the TRANSURANUS models, as well as a confidence interval for the results. The analysis was made through Monte Carlo sampling, where input values related to the geometry and composition of the fuel rod were taken from a normal distribution truncated around fabrication tolerance values. The generated samples were used as TRANSURANUS input data, and after numerous executions of the code, the results pertaining to the fuel center line temperature, fuel rod inner pressure and cladding strains were used to obtain a confidence interval and to make a variance based sensitivity analysis, showing that the models used in TRANSURANUS are additive in nature, and input interactions are not relevant to the code.

ABSTRACT This study aimed to analyze the economic feasibility of manufacturing frames in a carpentry company through two scenarios, including the production before and after modeling using operational research. The annual costs and revenues were quantified considering a horizon of 30 years. The economic analysis included the following criteria: Net Present Value (NPV), Equivalent Periodic Value (EPV) and Revenues Cost Ratio (R/C). The modeling was applied after analysis of the standard production using an objective function to maximize the company’s profit based on the quantity of each assortment to be produced. The standard production showed economic feasibility for all evaluated indicators, however implementing the operational research provided an increase of 57.54% for the NPV and EPV indicators, and 11.29% for the R/C ratio. In applying the sensitivity analysis after modeling, it was noticed that the value obtained for the NPV indicator was higher, even with a 10% increase in labor costs or in the price of wood, when compared to the standard production scenario before the modeling and without applying sensitivity analysis.

Purpose: The aim of this study was to analyze the relevance of profits in determining the market value of publicly traded companies in Brazil considering the effects of earnings management via discretionary accruals. Methodology: The research sample was composed of 211 different non-financial companies from [B]³ between 2013 and 2018. The data were analyzed initially from regressions with panel data and, additionally, as a measure of sensitivity analysis, through regressions estimated by minimum absolute deviations. Results: Unlike what was expected a priori in the survey, it was noticed that the economic results reported by companies, when segregated from the earnings management proxy, showed less informational power in predicting companies' market value than economic results in their entirety. This outcome is apparently in line with some recent national surveys (Martins, Paulo & Monte, 2016; Marçal & Macedo, 2019) that highlight the non-opportunistic aspect of earnings management, and there may be signs of a nuance of the Brazilian market in contemporaneity in this regard. Contributions of the Study: The results contribute in a practical way by making available to external users the effects of earnings management in the evaluation process of companies (specifically by demystifying the unanimous view of intent on the part of managers in the earnings management process). Nevertheless, a theoretical gap similar to that reported by Martins et al. (2016) is now partially supplied with these new findings. [ABSTRACT FROM AUTHOR]

Diamantino Martins, one of the main masters of the Braga School, was part of the founding group of the Portuguese Journal of Philosophy (Revista Portuguesa de Filosofia). He is the author of a vast philosophical work, and presents an original thought on natural evidence and immediate intuitive knowledge of God. The fine sensitivity and psychological analysis of the feeling of the divine in the deepest identity of the human being manifest, in his work, a penetrating understanding of the actuality of the question of God, very present in the return of the religious and the divine, in the literature of the end of last century. It is also situated in the innovative current of philosophical thought of contemporary Portuguese authors, about the philosophical treatment of the question of God, like Sampaio Bruno and Fernando Pessoa. [ABSTRACT FROM AUTHOR]

The reference evapotranspiration is an important agrometeorological parameter for planning and irrigation management and can be estimated by several methods. In the Brazilian Northeast, irregular and contingent water resources, studying evapotranspiration means optimizing irrigation management. This study aimed to analyze the influence of climate elements on the reference evapotranspiration calculated by the FAO-56 Penman-Monteith equation to the climatic elements of maximum and minimum temperature of the air, relative humidity, wind speed and insolation of a period of 53 Years, granted by INMET, of the city of Morada Nova in Ceará, whose climate according to the classification of Köppen is BSw'h '; Hot and semi-arid climate. The reference evapotranspiration was calculated according to the procedures suggested by FAO 56. The sensitivity analysis was based on the addition and decrease of one climatic element at a time in ± 5% up to the limit of ± 40% between -40% and -30% %, -20%, -15%, -10%, -5%, + 5%, + 10%, + 15%, + 20%, + 30% and + 40%, while maintaining the values of the other elements Constant. The results showed that the variation of the elements of the climate between dry and rainy season did not change the sensitivity of the Penmam-Monteith FAO 56 model to the evaluated climatic elements. The Penmam Motheith model, in the climatic conditions of Morada Nova, CE, is more sensitive to the elements of maximum temperature of the relative humidity of the air, followed by insolation, wind speed and minimum air temperature.

A mathematical model considering female and male individuals is proposed to evaluate vaccination strategies applied to control of HPV transmission in human population. The basic reproductive number of the disease, $R_0$, is given by the geometric mean of the basic reproductive number of female and male populations. The model has a globally asymptotically stable disease-free equilibrium whenever $R_0

ABSTRACT The main purpose of this research is to analyze the relationship between characteristics of hiring firms and the perception of auditors/accountants that provide services to them regarding complexity in the elaboration/disclosure of sensitivity analyses and risk management. We seek to analyze whether characteristics of firms that have a better level of disclosure could also be associated with the complexity perceived by the professionals that provide services to such firms concerning the information to do with sensitivity analyses and risk management. Information about risk management arouses considerable debate in the area of accounting and finance; nevertheless, how it is addressed, from the point of view of the professionals, still deserves more attention. The results of this study may lead to an improvement, or even a revision, of the standards related with sensitivity analyses and risk management involving financial instruments. The study sample was composed of respondents from South America, namely accountants and auditors from Brazil and Chile. The perception of complexity was evaluated through a structured questionnaire, which was applied using electronic forms. Regarding the explanatory variables, the quantitative model considers the following characteristics of hiring firms: auditor type; firm size; industry; listed firms; transparency; exporting firms. The main advancement provided by this research lies in it revealing that some characteristics of companies usually associated with better levels of disclosure are not necessarily reflected in the perception by accountants/auditors of lower levels of complexity in the elaboration/disclosure of sensitivity analyses and risk management.

A nonlinear form of innovation diffusion model consisting of two driving equations governed by two variables namely adopter and non-adopter population density is proposed to lay stress on the evaluation period. The model is analyzed qualitatively with stability theory, Hopf-bifurcation analysis by taking evaluation period as a control parameter to see the role of evaluation period in shaping the dynamics of adopter and non-adopters. The threshold value of evaluation period is determined beyond which small amplitude oscillations of adopter and non-adopter population occur and goes on decreasing with the increase in carrying capacity of non-adopter class. The sensitivity analysis of the state variables w.r.t. the model parameters is performed at a non-zero equilibrium point. The effect of external influences to achieve maturity stage is also discussed. The analytical results so obtained are verified through numerical simulations by using the Matlab software.

Copyright of JBES: Brazilian Journal of Health Economics / Jornal Brasileiro de Economia da Saúde is the property of JBES: Brazilian Journal of Health Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of ConTexto is the property of ConTexto and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this study was to evaluate the economic and financial viability of feeding systems for horses using Elephant-grass and corn silage, as food supplementation. The zootechnical and economic indicators for the characterization of the feeding systems were obtained together with a horse breeding farm of the Mangalarga Marchador breed. A 12-year horizon was projected for exploration of the activity and, based on the use of electronic spreadsheets, the cash flows were elaborated to verify the economic-financial viability. The economic indicators of profitability were used: net present value and internal rate of return, as well as the sensitivity and risk analyzes were performed in each feeding system. The systems were financially viable as they had a positive net present value at a 10% discount rate per year. The internal rate of return was 11.11% for the feeding system that adopted the supply of Elephant-grass, while for the feed system that used corn silage, the yield obtained was 11.46%. The purchase and sale prices of animals, especially embryo donor mares, were the items with the greatest influence on the results obtained for the net present value. The economic-financial risk for investment in food systems was classified as low. [ABSTRACT FROM AUTHOR]

Financial scenario systems on the final disposal of domestic sewage sludge are analyzed. Scenarios comprised Treatment Station, which disposes of solid residues produced for sanitary landfill, and Treatment Station that treats sewage sludge through a composting process for the production of fertilizers and the disposal of other solid wastes in the sanitary landfill. Data on inventory, infrastructure, labor, maintenance costs and warrants for functioning were obtained for the Treatment Station, with mean capacity of 3,356 m3 sludge/day. Economic indicators, net rate and internal return rate were used to analyze financial viability. Sensitiveness and risk analyses were performed to identify the items with the highest negative impact rates, coupled to financial risk, in the wake of market's simulated prices, by the Monte Carlo method. The station for the improvement of sewage sludge for the production of organic fertilizers had the best chance of receiving investments, with a 61.6% profit/year. [ABSTRACT FROM AUTHOR]

Copyright of Exacta is the property of Exacta - Engenharia de Producao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, a sensitivity analysis was performed to investigate the effect of thickness variation of bituminous layer in the structural responses of flexible pavements and, therefore in performance. For this, it used traffic data from a weigh station located at Km 28 of the Immigrants Highway, at state of Sao Paulo, whose data collection was realized in 2008. The loads deriving from traffic were applied to the computational program ELSYM5 to obtain structural responses related to damage such as fatigue cracks and rutting. With these values, the damage factors were calculated and then the sensitivity analysis related to the thickness variation of bituminous layer was performed. Through the obtained results was concluded that the variation of thickness of bituminous layer have an influence on structural responses, and that damage factors related to fatigue cracks were more sensitive than those factors related to rutting.

Copyright of Anuario do Instituto de Geociencias is the property of Universidade Federal do Rio de Janeiro, Instituto de Geociencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Esta pesquisa teve como objetivo determinar, mediante o cálculo do valor presente líquido (VPL), da taxa interna de retorno (TIR) e do Payback Econômico (PBE), a viabilidade econômica da produção de Alpinia purpurata, Etlingera elatior e Anthurium andraeanum, no Estado do Rio de Janeiro, bem como identificar e verificar, por meio da análise de sensibilidade, a influência de alguns fatores do sistema produtivo sobre a rentabilidade da atividade nas principais regiões produtoras. Os resultados mostram que a produção das espécies tropicais consideradas é uma atividade lucrativa e promissora para os agricultores no Estado do Rio de Janeiro. Porém, trata-se de um mercado em construção, cujos itens de maior impacto sobre a rentabilidade e o tempo de retorno do investimento (PBE) são o preço de venda do produto e o percentual de perdas da produção. Assim, a agregação de valor e o planejamento estratégico da produção são importantes medidas mercadológicas para a consolidação deste setor.The purpose of this study was to determine, through the calculation of the net present value (VPL), the internal return rate (TIR) and of the Economic Payback (PBE), the economic viability of the production of Alpinia purpurata, Etlingera elatior and Anthurium andraeanum in the Rio de Janeiro State, as well as to identify and to verify by means of sensitivity analysis the influence of some factors of the production system on the profitability of the activity in the main producing regions. The results showed that the production of the tropical species is a profitable and promising activity for the farmers in the State of Rio de Janeiro. However, it is a developing market, whose factors of greatest impact on the profitability and investment return time (PBE) are the selling price of the product and the percentage of production losses. Thus, the aggregation of value and strategic planning of the production are important market measures for the consolidation of this sector.

The impact of the installation of a large-scale photovoltaic (PV) system to the electric power grid management is analyzed in a series of two works: Part 1 and Part 2. The PV generation is estimated in Part 1. By applying the results of Part 1, the Guatemala’s electric power grid management is simulated with a virtually-installed large-scale PV system using a nonlinear analysis model in this work, Part 2. The thermal power plants reduced their operation in the simulation by installing the PV system, however the effect of the PV system installation to the plants is different in each thermal power plant. The contribution of the PV installation to the reduction of operation of the largest generation thermal plants is very limited or null, because of their high efficiency and low cost in operation. On the other hand, the middle-large generation thermal power plants reduce their operation after installing PV system in this simulation. The reduction of thermal plants’ operation becomes large, but its reduction gradient becomes small as the PV installing capacity becomes large.

Potential parameters sensitivity analysis for helium unlike molecules, HeNe, HeAr, HeKr and HeXe is the subject of this work. Number of bound states these rare gas dimers can support, for different angular momentum, will be presented and discussed. The variable phase method, together with the Levinson's theorem, is used to explore the quantum scattering process at very low collision energy using the Tang and Toennies potential. These diatomic dimers can support a bound state even for relative angular momentum equal to five, as in HeXe. Vibrational excited states, with zero angular momentum, are also possible for HeKr and HeXe. Results from sensitive analysis will give acceptable order of magnitude on potentials parameters.

SUSCEPTIBILITY MODELS FOR SHALLOW TRANSLATIONAL SLIDES. Evaluationand maping in the Region to the North of Lisbon. Over the last decade, Geographic Information Systems (GIS) have enabled the creation and the rigorous crossing and computation of cartographic thematic layers. Thus, it has been possible to increase the number of variables within data‑driven landslide susceptibility models. In this context, sensitivity analysis is an analytical tool used to assess the relative importance of the landslide predisposing factors into a particular landslide susceptibility model. In this study, a sensitivity analysis of shallow translational slides susceptibility models is made for two test sites in the Region to the North of Lisbon, which have the same geologic and geomorphologic context: the Fanhões‑Trancão test site and the Lousa‑Loures test site. The resultsobtained allowed for the identification of 3 variables that have the highest spatial association with shallow translational slides in both test sites: slope angle, geomorphology and slope aspect. Furthermore, results prove the absence of a linear relationship between the number of variables within a landslide predictive model and the model prediction capacity. In addition to this, it is shown that reliable landside susceptibility maps can be produced based on a small group of variables that have a strong spatial relationship with slope movements.

Los modelos matemáticos son herramientas útiles para la predicción de las pérdidas de suelo por erosión hídrica. El desarrollo reciente del modelo WEPP y su utilización para evaluar los riesgos de erosión en pastizales naturales ha significado un avance interesante en el campo de la erosión y la conservación de suelos de estos ecosistemas. En este trabajo examinamos la eficiencia del modelo WEPP para predecir los procesos hidrológicos y de erosión del suelo en los pastizales naturales semiáridos del noreste de la provincia de Chubut. Se identificaron tres comunidades de plantas ubicadas a lo largo de un gradiente de degradación del suelo: estepa herbácea con arbustos aislados (EH), estepa herbáceo-arbustiva (EHA) y estepa arbustiva degradada (EA). En cada una de estas comunidades se aplicó una lluvia simulada (100 mm h-1 durante 30 min) sobre parcelas de 1 m² (0,6 x 1,67 m) y se colectó el escurrimiento y los sedimentos totales. A partir de los datos de la condición superficial de cada parcela se estimó el escurrimiento y la producción de sedimentos mediante el modelo WEPP. En este trabajo se observó una baja eficiencia del modelo WEPP para predecir el escurrimiento (Eficiencia, E = 0,14) y la erosión del suelo (E = -0,93). La predicción del escurrimiento y pérdida de suelo del modelo WEPP mostró mayor sensibilidad a cambios en los parámetros de lluvia y pendiente del terreno y una sensibilidad moderada a cambios en la cobertura, textura, erodabilidad del suelo y conductividad hidráulica efectiva. El escurrimiento y la producción de sedimentos estimados por WEPP fueron significativamente diferentes en las distintas comunidades de plantas (p < 0,05). La diferencia entre los valores medios estimados y observados varió en las distintas comunidades. Así, el escurrimiento medio estimado fue un 55,5% más elevado en la EH y la producción de sedimentos fue un 69,6; 62,7 y 17,5% más baja en la EH, EHA y EA, respecto a los valores observados. El uso del modelo WEPP en los ecosistemas de pastizales naturales constituye una importante herramienta para estimar la erosión. Sin embargo, estos resultados sugieren que es necesario calibrar el modelo para las condiciones locales e incorporar una estratificación de los pastizales de acuerdo a las diferentes unidades de suelo y vegetación.Mathematical models are useful tools to predict soil loss by water erosion. The recent development of the WEPP model and its use in assessing the risks of erosion in rangelands has led to significant advances in the field of erosion and soil conservation of these ecosystems. In this work we examine the efficiency of the WEPP model in predicting the hydrological processes and soil erosion in semiarid rangelands of the northeast Chubut Province. Three plant communities along a soil degradation gradient were identified: grass with scattered shrubs (EH), grass-shrubs (EHA), and degraded shrub steppes (EA). In each of these communities simulated rainfall (100 mm h-1 for 30 min) was applied on 1 m² (0.6 x 1.67 m) plots and total runoff and sediment production were collected. Using the soil surface condition data from each plot, runoff and sediment production were estimated by means of the WEPP model. We found a low efficiency of the WEPP model to predict runoff (Efficiency, E = 0.14) and soil erosion (E = -0.93). The WEPP-estimated runoff and soil losses showed high sensitivity to changes in rainfall and slope parameters and moderate sensitivity to changes in soil cover, texture, soil erodability and effective hydraulic conductivity. The runoff and sediment production estimated by the WEPP model were significantly different among plant communities (p < 0.05). The difference between the estimated and observed mean values varied in the different plant communities: runoff according to the WEPP model was 55.5% greater in the EH and sediment production was 69.6, 62.7 and 17.5% lower, respectively, in the EH, EHA, and EA than the observed values. These results suggest that it is necessary to calibrate the model for local conditions and to incorporate rangeland stratification according to the different soil-vegetation units.

One of the main purposes of epidemiological studies is to estimate causal effects. Causal inference should be addressed by observational and experimental studies. A strong constraint for the interpretation of observational studies is the possible presence of unobserved confounders (hidden biases). An approach for assessing the possible effects of unobserved confounders may be drawn up through the use of a sensitivity analysis that determines how strong the effects of an unmeasured confounder should be to explain an apparent association, and which should be the characteristics of this confounder to exhibit such an effect. The purpose of this paper is to review and integrate two independent sensitivity analysis methods. The two methods are presented to assess the impact of an unmeasured confounder variable: one developed by Greenland under an epidemiological perspective, and the other developed from a statistical standpoint by Rosenbaum. By combining (or merging) epidemiological and statistical issues, this integration became a more complete and direct sensitivity analysis, encouraging its required diffusion and additional applications. As observational studies are more subject to biases and confounding than experimental settings, the consideration of epidemiological and statistical aspects in sensitivity analysis strengthens the causal inference.Um dos principais objetivos dos estudos epidemiológicos é a estimação de efeitos causais. E a inferência causal deve ser discutida tanto por estudos experimentais quanto por estudos observacionais. Uma importante limitação na interpretação causal de estudos observacionais é a possível presença de confundidores não observados (hidden bias). Uma estratégia para avaliar o possível efeito de um confundidor não observado é através de uma análise de sensibilidade, que determina quão forte deveriam ser os efeitos de um confundidor não observado de modo a explicar uma aparente associação. A proposta deste artigo é rever e integrar dois métodos independentes de análise de sensibilidade: um devido a Greenland, sob uma perspectiva epidemiológica; e outro devido a Rosenbaum, sob uma perspectiva estatística. A combinação de questões estatísticas e epidemiológicas torna a análise de sensibilidade mais completa e direta, e deve estimular sua necessária difusão e mais aplicações. Como os estudos observacionais são mais sujeitos a vieses e confundimento, uma análise de sensibilidade considerando aspectos estatísticos e epidemiológicos fortalece o processo de inferência causal.

Realizou-se neste estudo uma análise econômica de sistemas de produção para vacas em lactação manejadas em pastagem de capim-mombaça recebendo diferentes fontes de suplementação volumosa durante a época seca do ano. As suplementações fornecidas foram: pastagem de aveia-preta, cana-forrageira com ureia e silagem de sorgo. Utilizaram-se como indicadores econômicos o valor presente líquido (VPL) e a taxa interna de retorno (TIR). Para cada sistema de produção estudado, foi construído um fluxo de caixa, com sua particularidade e índices de desempenhos produtivo e reprodutivo, obtidos experimentalmente. Os fluxos de caixa foram construídos mensalmente para um período de 12 anos e os VPL dos sistemas foram calculados aplicando-se taxas de desconto de 6, 8, 10 e 12% ao ano. Com uma taxa anual de desconto de 8%, todos os sistemas de produção foram viáveis financeiramente. O capital investido apresentou TIR anuais de 11,91% para pastagem de aveia-preta, 9,43% para cana-forrageira e ureia e 8,46% para silagem de sorgo. O item de maior impacto nos resultados econômicos dos sistemas, de acordo com a análise de sensibilidade, foi o preço de venda do leite produzido.An economical analysis of milk production systems was made with lactating cows on Mombaça grass pasture receiving different sources of roughage supplementation during the dry season. The supplementations were: black oat pasture, forage sugarcane with urea and sorghum silage. The economical indicators used were: net present value (NPV) and internal rates of return (IRR). For each production system studied one cash flow was used with their particularities and productive and reproductive performances index, obtained experimentally. The cash flows were built monthly, for a 12 years period and the NPV of the systems were calculated applying discount rates of 6, 8, 10 and 12% a year. At an annual discount rate of 8% all the production systems were financially viable. The invested capital showed annual IRR of 11.91% for black oat pasture, 9.43% for forage sugarcane and 8.46% for sorghum silage. The sensitivity analysis showed that the milk selling price had greatest economic impact on the profitability of the systems.

The objective in this work was to evaluate the economicity of the finishing phase on feedlot of F1 Red Angus × Nellore (½ RA ½ N) and Blond D'Aquitaine × Nellore (½ BA ½ N) crossbred young bulls slaughtered at 480, 520 and 560 kg of body weight. Thirty-six F1 crossbred young bull with 20 months of initial average age: 18 ½RA½ N and 18 ½N½ BA were allotted to a completely randomized design in a 2 × 3 factorial arrangement (genetic group × slaughter weight), with six replicates. The ½ BA ½ N young bulls slaughtered at 480 kg had the highest carcass gain (kg/day), feed efficiency, gross income (R$/day), gross profit of feed (R$/day), break-even cost of the diet (@/t DM) and cost:benefit ratio. The ½ BA ½ N young bulls also had higher dressing percentage than ½ RA ½ N young bulls. As the slaughter weight rised the dressing percentage, feed:gain ratio, feed cost (R$/@ and R$/day) and break-even point (kg/day) increased; while the gross feed profit (R$/@) decreased. The bioeconomic multivariate nutritional index had better association with the profitability of the finishing phase of beef cattle on feedlot. Sensitivity analysis did not influence the results obtained. The benefit was lower than the feed cost from exchange relation of four (4) @/t DM of the diet. F1 Blond D'Aquitaine × Nellore crossbred young bulls slaughtered at 480 kg of body weight showed the best bioeconomic efficiency.Objetivou-se verificar a economicidade da fase de terminação em confinamento de tourinhos mestiços F1 Red Angus × Nelore (½ RA ½ N) e F1 Blonde D'Aquitaine × Nelore (½ BA ½ N) abatidos com 480, 520 e 560 kg de peso corporal. Trinta e seis bovinos mestiços F1, tourinhos, com 20 meses de idade média inicial: 18 ½ RA ½ N e 18 ½ BA ½ N foram distribuídos a um delineamento experimental inteiramente casualizado em arranjo fatorial 2 × 3 (grupos genético × peso de abate), com seis repetições. Os tourinhos ½ BA ½ N abatidos com 480 kg apresentaram maior ganho de carcaça (kg/dia), eficiência alimentar, valor de produção (R$/dia), saldo de alimentação (R$/dia), custo de nivelamento da dieta (@/t MS) e relação benefício:custo. O rendimento de carcaça dos tourinhos ½ BA ½ N foi maior que o dos tourinhos ½ RA ½ N. À medida que se elevou o peso de abate, o rendimento de carcaça, a conversão alimentar, o custo de alimentação (R$/@ e R$/dia) e o ponto de nivelamento da dieta (kg/dia) aumentaram; ao passo que o saldo de alimentação (R$/@) diminuiu. O índice nutricional multivariado bioeconômico indicou melhor associação com a rentabilidade da fase de terminação de bovinos em confinamento. A análise de sensibilidade não influenciou os resultados obtidos. O benefício foi menor que o custo de alimentação se considerada a relação de troca a partir de 4 @/t MS da dieta. Tourinhos mestiços F1 Blonde D'Aquitaine × Nelore abatidos com 480 kg de peso corporal apresentam melhor eficiência bioeconômica.

A importância econômica de possíveis características biológicas a serem incluídas em objetivos de seleção para diferentes sistemas de produção de bovinos da raça Nelore, mediante o cálculo dos seus valores econômicos foi avaliada nesta pesquisa. Com base em informações de desempenho e parâmetros biológicos e econômicos, foram simulados diferentes sistemas de produção (ciclos de cria e completo) para dois rebanhos. O rebanho 1, com ciclo de cria (Ccr), ciclo completo (Cco) e ciclo completo com venda de reprodutores (CcoR), é um rebanho elite no qual é desenvolvido um programa seleção. Parte deste rebanho é também destinada à produção de animais comerciais. O rebanho 2 é um rebanho exclusivamente comercial, com Ccr e Cco. Os valores econômicos foram calculados usando-se um modelo bio-econômico, para as seguintes características: peso (PD) e taxa de desmama (TD), peso da vaca adulta (PVA), ganho médio diário no confinamento (GMD), pesos ao abate (PA) e de carcaça (PC), peso final dos tourinhos (PFT), rendimento de carcaça (RC) e consumo alimentar no confinamento (CAc) e em pastagem (CAp). Para os sistemas de ciclo completo e de ciclo completo com venda de reprodutores e CcoR (Cco e CcoR), os valores econômicos variaram de R$ 0,34 a R$ 0,40 para PD, R$ 3,51 a R$ 10,15 para TD, -R$ 0,16 a R$ 0,09 para PAV, R$ 0,32 a R$ 0,76 para GMDc, R$ 1,09 a R$ 1,17 para PA; R$ 2,03 a R$ 2,19 para PC, R$ 23,89 a R$ 28,61 para RC, e R$ 11,85 para PFT, - R$0,45 para CAc e - R$ 0,03 para CAp. A taxa de desmama e o rendimento de carcaça foram as características de maior impacto no lucro anual dos dois rebanhos. As análises de sensibilidade demonstraram que, de modo geral, possíveis mudanças nos preços de insumos e produtos influenciariam de forma mais significativa os valores econômicos nos sistemas de produção nos quais esses preços eram mais elevados nas situações básicas.Economic values were calculated to evaluate the economic importance of possible traits to be included in breeding goals, for different production systems of Nelore cattle. Two types of production systems (cow-calf and complete breeding cycles) were simulated for two types of herds. Herd 1 was defined as a nucleus herd (where selection was carried out and a percentage of animals were also raised for commercial purposes), with cow-calf (Cc), complete breeding cycle (Cbc) and complete breeding cycle with sales of animals for reproduction (CbcR). Herd 2 was defined as an exclusively commercial herd, with cow-calf cycle (Cc) and complete breeding cycle (Cbc). Using a bio-economic model, economic values were calculated for the following traits: weaning weight (WW), weaning rate (WR), mature weight (MW), average daily gain in feed-lot (DAG), slaughter (WS) and carcass weights (WC), young bulls' final weight (FWYB), dressing percentage (DP), feed-lot (FLFI) and pasture feed intakes (PFI). The economic values for Cbc and CbcR (herds 1 and 2) ranged from R$ 0.34 to R$ 0.40 for WW, R$ 3.51 to R$ 10.15 for WR, -R$ 0.16 to R$ 0.09 for MW, R$ 0.32 to R$ 0.76 for FLFI, R$ 1.09 to R$ 1.17 for WS; R$ 2.03 to R$ 2.19 for WC, R$ 23.89 to R$ 28.61 for YG, R$ 11.85 for FWYB, - R$ 0.45 for FLFI and - R$ 0.03 for PFI. WR and DP presented the largest impacts on annual profits in both herds. Sensitivity analyses indicated that, in general, possible changes in prices of production components and products would exert a greater influence on the economic values for those production systems with higher prices in the basic situation.

In studies assessing the effects of a given exposure variable and a specific outcome of interest, confusion may arise from the mistaken impression that the exposure variable is producing the outcome of interest, when in fact the observed effect is due to an existing confounder. However, quantitative techniques are rarely used to determine the potential influence of unmeasured confounders. Sensitivity analysis is a statistical technique that allows to quantitatively measuring the impact of an unmeasured confounding variable on the association of interest that is being assessed. The purpose of this study was to make it feasible to apply two sensitivity analysis methods available in the literature, developed by Rosenbaum and Greenland, using an electronic spreadsheet. Thus, it can be easier for researchers to include this quantitative tool in the set of procedures that have been commonly used in the stage of result validation.Em estudos que avaliam o efeito de uma dada variável de exposição e um determinado desfecho de interesse, uma situação de confusão pode ser caracterizada pela falsa aparência de que a variável de exposição produz o desfecho de interesse quando, de fato, o efeito observado se deve a um fator de confundimento que está presente. Entretanto, é pouco freqüente a utilização de técnicas quantitativas para determinar a influência potencial de confundidores não mensurados. A análise de sensibilidade é uma técnica estatística que permite uma medida quantitativa do impacto de uma variável confundidora não mensurada na associação de interesse que está sendo avaliada. O objetivo do artigo foi viabilizar a aplicação, por meio de planilha eletrônica, de dois métodos de análise de sensibilidade disponíveis na literatura, desenvolvidos por Rosenbaum e Greenland. Dessa forma, é possível facilitar ao pesquisador a incorporação desse ferramental quantitativo ao conjunto de procedimentos que já são comuns na etapa de validação dos resultados.

Dois experimentos foram realizados com o objetivo de avaliar níveis de PB em suplementos para novilhos mestiços em pastagem de Panicum maximum cv. Mombaça durante o período de transição seca/águas. Os suplementos, à base de milho e grão de soja triturados, foram formulados para apresentar 8,0; 16,0 e 24,0% de PB e foram fornecidos na quantidade de 1,0 kg/dia. No primeiro experimento, foram avaliados o desempenho produtivo e a eficiência econômica de 20 novilhos mestiços Holandês x Zebu, não-castrados, com 19 meses de idade e 339,4±14,8 kg de PV inicial. O ganho médio diário e o ganho de peso total aumentaram de forma linear de acordo com os níveis de proteína nos suplementos. Os ganhos observados foram de 0,992; 1,142 e 1,261 kg/dia, respectivamente, para os suplementos com 8,0; 16,0 e 24,0% de PB. A avaliação econômica dos suplementos comprovou maior eficiência econômica do suplemento com 24% de PB. No segundo experimento, quatro novilhos mestiços (peso médio de 400 kg) fistulados no rúmen e no esôfago foram utilizados para avaliar a influência dos níveis de proteína sobre o pH e a concentração de amônia ruminal. O pH não foi alterado, mas a concentração ruminal de N-NH3 aumentou de forma linear com os níveis de proteína do suplemento. Os níveis amoniacais médios observados com os suplementos contendo 8,0; 16,0 e 24,0% de PB foram de 8,41; 10,69 e 12,92 mg/dL, respectivamente.Two experiments were conducted to evaluate different crude protein (CP) levels of a mixture of mineral and concentrate (multiple supplement) fed to crossbreed steers grazing Panicum maximum cv. Mombaça pasture during the transition between the dry and the rainy season. The multiple supplement contained ground corn and soybean grains and was formulated to yield 8.0, 16.0 or 24.0% of CP. Each animal received 1.0 kg of the multiple supplement per day or only ad libitum mineral mix (control treatment). In the first trial, 20 crossbred steers averaging 19 months of age and 339.4±14.8 kg of body weight were used. The average daily gain (ADG) increased linearly from 0.992 to 1.258 kg/d when the CP level of the supplement increased from 8.0 to 24%. Total weight gain also increased linearly by increasing the CP level of the supplement. Economical analysis of the supplements showed greater gross income for the supplement containing 24% CP. In the second trial, four crossbreed steers fitted with ruminal and esophageal cannulas and averaging 400 kg of body weight were used to investigate different CP levels of the supplements on ruminal pH and ruminal ammonia ruminal concentration. The different CP levels of the supplement did not significantly change ruminal pH. However, ruminal ammonia increased linearly from 8.41 to 12.2 mg/dL when the CP level of the supplement increased from 8.0 to 24%.

Avaliou-se financeiramente um modelo de sistema produtivo de leite produzido em pasto na região Norte Fluminense - RJ. Foi elaborada uma planilha de fluxo de caixa (horizonte de 20 anos), a partir da qual calcularam-se os indicadores: valor presente líquido (VPL a 6 e 10%) e taxa interna de retorno (TIR). Cada fator envolvido nas receitas ou nas despesas do projeto foi submetido à análise de sensibilidade para que fossem identificados aqueles com maiores pesos na redução dos indicadores calculados. Realizou-se simulação de Monte Carlo, visando avaliar a probabilidade de ocorrência para determinados valores financeiros associados ao risco de divergências nos itens do projeto. Os resultados demonstraram viabilidade financeira para o sistema proposto (VPL a 6 e 10%, R$197.880,00 e R$8.067,00, respectivamente, e TIR 10,2%). A rentabilidade foi afetada, em ordem decrescente, pelos fatores: preço do leite, aquisição de vacas nos primeiros anos do projeto, preço das vacas descartadas, mão-de-obra e preço do concentrado para os animais adultos. Os resultados da simulação de Monte Carlo demonstraram elevada probabilidade (39%) de a rentabilidade do projeto ser inferior ao rendimento da poupança, representando alto risco na adoção do sistema.The study aimed to evaluate milk production under grazing system in the North Region of Rio de Janeiro State. The net present worth (NPWs of 6 and 10%) and internal rate of return (IRR) were calculated from the cash flow chart on a 20-year basis. Sensitivity analyses were performed to evaluate the effect of the income or expense factors on the net present worth (6 and 10%) and the internal rate of return. A Monte Carlo Method was carried out to evaluate the probabilities of occurrence for certain financial values associated to the risk of deviation in the project itens. The results showed financial feasibility for the proposed system (NPWs of 6% and 10% R$197,880.00 and R$8,067.00, respectively; IRR 10.2%). The profitability was affected in decreasing order by the following factors: price of milk, purchase of cows in the first years of the project, price of culled cows, labor and the price of the concentrate for adult animals. The results of the Monte Carlo simulation indicated high probabilities (39%) of the profitability to be smaller than the interest of the saving account, showing high economic risk of the production system.

Utilizando-se como padrão as medidas lisimétricas de um gramado, avaliaram-se os resultados de estimativas de ETo obtidas com Dar_méd oriundos de 14 métodos para seu cálculo. Tais comparações permitiram separar os métodos de cálculo de Dar_méd em três grupos, ou seja: um grupo resultou sempre em superestimativa de ETo; em outro, a tendência foi de sempre subestimar, e no último a tendência foi de superestimar valores baixos (< 4,5 mm dia-1) e de subestimar valores altos de ETo. Não foram observadas diferenças significativas (teste t; p < 0,05) de ETo, em função dos métodos de Dar_méd ao utilizar a média horária da temperatura e/ou umidade relativa do ar em relação aos determinados com a média dos valores máximo e mínimo desses elementos. Dos métodos propostos pelo boletim FAO56, apenas o que utilizou a umidade relativa média para calcular a pressão parcial de vapor d'água (e a) apresentou estimativa satisfatória. As melhores estimativas de ETo foram obtidas com os métodos de Dar_méd, que utilizaram média da temperatura do ar na determinação da pressão de saturação (e s), e média da umidade relativa para ea. A utilização do déficit de pressão de saturação em um único horário (9 e 10 h local), como representativo para o Dar_méd, mostrou-se boa alternativa na estimativa da ETo, para as condições climáticas de Piracicaba - SP.The results of the evapotranspiration obtained with the Dair_avg proceeding from 14 methods were evaluated, by using the lysimetric measures of a sward. These comparisons allowed to separate the Dar_avg calculating methods into three groups: a group always resulted into an overestimate ETo; in other one always tended to underestimating the ETo; and in the last tended to overestimating the low values (

OBJECTIVE: Sensitivity analysis was applied to a mathematical model describing malaria transmission relating global warming and local socioeconomic conditions. METHODS: A previous compartment model was proposed to describe the overall transmission of malaria. This model was built up on several parameters and the prevalence of malaria in a community was characterized by the values assigned to them. To assess the control efforts, the model parameters can vary on broad intervals. RESULTS: By performing the sensitivity analysis on equilibrium points, which represent the level of malaria infection in a community, the different possible scenarios are obtained when the parameters are changed. CONCLUSIONS: Depending on malaria risk, the efforts to control its transmission can be guided by a subset of parameters used in the mathematical model.OBJETIVO: Aplicar a análise da sensitividade ao controle de transmissão de malária a um modelo, considerando o aquecimento global e as condições socioeconômicas locais. MÉTODOS: O modelo para a transmissão de malária proposto foi obtido em função de vários parâmetros. A prevalência de malária, em uma comunidade, foi caracterizada pelos valores desses parâmetros. Para estudar os efeitos dos mecanismos de controle, os valores dos parâmetros do modelo são variados em grandes intervalos. RESULTADOS: A análise da sensitividade do ponto de equilíbrio, que representa o nível de infecção de malária em uma comunidade, oferece os possíveis cenários resultantes da variação dos parâmetros do modelo. CONCLUSÕES: Dependendo-se do nível de risco de malária, as melhores formas de mecanismos de controle da transmissão de malária são dadas por um subconjunto de parâmetros do modelo.