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Power system simulation is vital for designing and evaluating the performance of electrical system protection and control devices. Although several commercial simulators exist, most are expensive and not open-source code. It is essential to develop educational and research simulators that can prepare students, allow researchers to develop new methodologies, and assist system operators in making decisions. This paper aims to present a computer simulation platform called AnaDyn (dynamic analysis), a non-commercial and open-source platform. AnaDyn is an educational/research platform that allows dynamic (transient stability), quasi-steady-state simulation, modal, and power flow analysis. Short- and long-term studies of voltage, frequency, and rotor angle instability problems can be performed. The main characteristics of AnaDyn are quasi-steady-state simulation, in which the equations are not simplified; easy integration with other tools and toolboxes, since AnaDyn is developing in MATLAB; flexible modeling that allows the inclusion of new devices and controller tests. The detailed modeling of various power system devices, the description of the numerical solution method, and the interface are also presented in this work. The platform is validated by comparing a test system's results with those obtained with Brazil's most popular commercial software. The main potentials of quasi-steady-state simulation are also presented. The results indicate that AnaDyn is efficient for educational and research studies on the stability of short- and long-term electrical systems. [ABSTRACT FROM AUTHOR]

Leishmaniasis is a public health concern, especially in Brazil and India. The drugs available for therapy are old, cause toxicity and have reports of resistance. Therefore, this paper aimed to carry out initial structure-activity relationships (applying molecular docking and dynamic simulations) of arylindole scaffolds against the pteridine reductase (PTR1), which is essential target for the survival of the parasite. Thus, we used a series of 43 arylindole derivatives as a privileged skeleton, which have been evaluated previously for different biological actions. Compound 7 stood out among its analogues presenting the best results of average number of interactions with binding site (2.00) and catalytic triad (1.00). Additionally, the same compound presented the best binding free energy (−32.33 kcal/mol) in dynamic simulations. Furthermore, with computational studies, it was possible to comprehend and discuss the influences of the substituent sizes, positions of substitutions in the aromatic ring and electronic influences. Therefore, this study can be a starting point for the structural improvements needed to obtain a good leishmanicidal drug. [ABSTRACT FROM AUTHOR]

The Earth-Air Heat Exchanger (EAHE) is a device where the external ambient air is cooled or heated when circulating inside ducts buried in the soil, which can bring benefits in terms of reducing energy consumption and providing thermal comfort conditions. This system has been employed in several countries in different climatic contexts, however, little explored in Brazil. The use of this technology in conjunction with bioclimatic strategies benefits buildings, increasing their efficiency. This study aims to evaluate the thermal performance of an EAHE alongside optimization parameters of the building envelope in two Brazilian bioclimatic zones and propose strategies that enhance energy efficiency in buildings. The study consists of the validation and verification of a computational model and the thermal evaluation of a Social Housing (SH), in which characteristics of solar orientation, thermal envelope, and the installation of an EAHE will be modified, combined, and investigated in the proposed models. These evaluations were conducted through dynamic simulation with the EnergyPlus™ software. The results demonstrate that the installation of an EAHE in SH brings improvements in the thermal performance of environments, thus contributing that future projects can rely on validated references and parameters. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an object-oriented framework to perform dynamical studies in electrical power systems. The proposed methodology is also useful to the development, upgrade and maintenance of software for power system studies. The framework was designed to be used by developers of power system software. Based on software engineering concepts, user''s requirements are, firstly, mapped to atomic classes which, in turn, are subsequently used to build state-space representation for each dynamic device in the power system under study, such as electrical generators, turbines and automatic controllers. The developed framework automates the whole process of building a global system model, providing a standard space-state model suitable for implementing by direct code in C++ language. By using the proposed methodology, a power system simulation tool was specially developed to study electromechanical phenomena observed at Tucuruí hydroelectric power plant, a large power plant of the Brazilian Interconnected Power System. The results were validated by comparing the simulated to the actual plant response obtained from field tests carried out at the Tucuruí power plant. The results have shown a very good level of performance of the developed simulator system. The simulator was able to reproduce the dominant dynamical phenomena observed at the Tucuruí power plant. [Copyright &y& Elsevier]

The present work proposes an extended model representing part of a huge aluminum industry load for short-term voltage stability investigations in time domain. The efforts were concentrated in the expansion of the industrial power distribution system model including explicit representation of the main transformers, capacitors, feeders and induction motors. The extended model is validated through a comparison between computer simulation results and the industry/power system utility recordings. A real sequence of events which took place in the Brazilian North Power System in the year of 2002 causing a complete industry breakdown (loss of bulk supply) was considered here for this purpose. [ABSTRACT FROM AUTHOR]

In a new concept of offloading operation, the oil from a spread moored FPSO is transferred to a conventional Tanker with an intermediate Cargo Transfer Vessel (CTV) equipped with a DP system. A comprehensive numerical analysis of the CTV offloading operation is here developed considering the sea states in the Libra Field, Brazil. First, the environmental loads on the vessels were estimated. Current and wind forces coefficients were obtained using the CFD software StarCCM+, while wave coefficients were obtained using WAMIT. For the 10-year metocean data, the multi-body static equilibrium configurations of the system – composed of the CTV, Conventional Tanker and Tugboat - were calculated. With those results, it was possible to estimate the downtime considering different offloading sectors and to compare with the DP Shuttle Tanker operation. Finally, a 5-day campaign of real-time simulations was carried out with the presence of DP Operators and captains, to verify critical conditions, considering the human factor. Each vessel was simulated in an individual cabin. For the simulations, the real DP System was integrated with the numerical simulator in a Hardware-in-the-loop configuration, resulting in a more realistic simulation. • Fast and real-time simulators are used to estimate the uptime of a complex multi-body offloading operation. • The real DP System is integrated with the simulator in a hardware-in-the-loop architecture, better representing the reality. • Extra terms in the DP logic eliminate the longitudinal motion instability of a large tanker coupled to the DP vessel. [ABSTRACT FROM AUTHOR]

• A dynamic climate change impact evaluation framework is proposed. • Bamboo bio-concrete is a good climate change mitigation and adaptation alternative. • Bamboo bio-concrete presents a reliable carbon-thermal energy solution. • Bamboo bio-concrete provides a promising alternative for developing countries. This study aims to present a framework to quantify the climate change impact during the buildings' life cycle. The proposed framework is tested on a bamboo bio-concrete (BBC) building and compared with conventional constructive systems, in a Brazilian housing project considering six cities using Dynamic Life Cycle Assessment (DLCA) and thermal energy simulation. The increase of BBC in the building envelope, from 10 cm to 20 cm, leads to the improvement of carbon stock and reduces operational carbon. The BBC can be considered a potential alternative for climate change mitigation and adaptation and developed where bamboo is an available source. [ABSTRACT FROM AUTHOR]

• The leishmanicidal activity of a triazole-phthalimide derivative (PT4) was evaluated. • PT4 decrease the growth and survival of promastigote and amastigotes. • PT4 showed inhibitory potential over the CYP51 enzyme of Leishmania spp. • PT4 induced an increase in ROS and depolarization of the mitochondrial membrane. • Our results pointed PT4 as a promissory agent against Cutaneous Leishmaniasis. Organic compounds obtained by click chemistry reactions have demonstrated a broad spectrum of biological activities being widely applied for the development of molecules against pathogens of medical and veterinary importance. Cutaneous leishmaniasis (CL), caused by intracellular protozoa parasite of genus Leishmania , comprises a complex of clinical manifestations that affect the skin and mucous membranes. The available drugs for the treatment are toxic and costly, with long periods of treatment, and the emergence of resistant strains has been reported. In this study we investigated the in vitro effects of a phthalimide-1,2,3-triazole derivative, the 4-Phenyl-1-[2-(phthalimido-2-yl)ethyl]-1H-1,2,3-triazole (PT4) obtained by click chemistry , on mammalian cells and on L. amazonensis and L. braziliensis , the causative agents of CL in Brazil. In silico ADMET evaluation of PT4 showed that this molecule has good pharmacokinetic properties with no violation of Lipinski's rules. The in vitro assays showed that PT4 was more selective for both Leishmania species than to mammalian cells. This compound also presented low cytotoxicity to mammalian cells with CC 50 > 500 μM. Treatment of promastigote forms with different concentrations of PT4 resulted in ultrastructural alterations, such as plasma membrane wrinkling, shortening of cell body, increased cell volume and cell rupture. The molecular dynamic simulations showed that PT4 interacts with Lanosterol 14 α-demethylase from Leishmania, an essential enzyme of lipid synthesis pathway in this parasite. Our results demonstrated PT4 was effective against both species of Leishmania. PT4 caused a decrease of mitochondrial membrane potential and increased production of reactive oxygen species, which may lead to parasite death. Taken together, our results pointed PT4 as promissing therapeutic agent against CL. [ABSTRACT FROM AUTHOR]