Spatial clustering of molecular dynamics trajectories in protein unfolding simulations

Molecular dynamics simulations is a valuable tool to study protein unfolding in silico. Analyzing the relative spatial position of the residues during the simulation may indicate which residues are essential in determining the protein structure. We present a method, inspired by a popular data mining technique called Frequent Itemset Mining, that clusters sets of amino acid residues with a synchronized trajectory during the unfolding process. The proposed approach has several advantages over traditional hierarchical clustering.The authors acknowledge the support of the "Fundacao para a Ciencia e Tecnologia,Portugal, and the program FEDER, through grant PTDC/BIA-PRO/72838/2006 (to PJA and RMMB) and the Fellowships SFRH/BPD/42003/2007(to PGF) and SFRH/BD/16888/2004 (to CGS). We thank the Center for Computational Physics, Departamento de Fisica, Universidade de Coimbra, for the computer resources provided for the MD simulations

Mining approximate motifs in time series

The problem of discovering previously unknown frequent patterns in time series, also called motifs, has been recently introduced. A motif is a subseries pattern that appears a significant number of times. Results demonstrate that motifs may provide valuable insights about the data and have a wide range of applications in data mining tasks. The main motivation for this study was the need to mine time series data from protein folding/unfolding simulations. We propose an algorithm that extracts approximate motifs, i.e. motifs that capture portions of time series with a similar and eventually symmetric behaviour. Preliminary results on the analysis of protein unfolding data support this proposal as a valuable tool. Additional experiments demonstrate that the application of utility of our algorithm is not limited to this particular problem. Rather it can be an interesting tool to be applied in many real world problems.Fundação para a Ciência e a Tecnologia (FCT).Fundo Europeu de Desenvolvimento Regional (FEDER) - POCTI/BME/49583/2002; SFRH/BD/13462/2003; SFRH/BD/16888/2004

An experimental investigation of the effects of gas solubility on the properties of horizontal slug flow

The present work investigates the effects of gas solubility on the fluid dynamic properties of a horizontal two-phase slug flow. Measurements of the size distributions of the liquid slug and of the long bubbles are provided, as well as local measurements of the liquid velocity in the slug, the velocity in the liquid film, the velocity of propagation of the nose of the long bubbles and the pressure drop. These parameters were obtained through two optical techniques: Shadow Sizer (SS) and Particle Image Velocimetry (PIV). The experiments indicate that the solubility has a substantial influence on the flow properties resulting, in particular, in a significant reduction of the local pressure gradient over a relatively short distance (8 m). The data are compared with modified versions of the mechanistic models of Dukler and Hubbard (Dukler, A.E., Hubbard, M., 1975, A model for gas–liquid slug flow in horizontal and near horizontal tubes, Ind. Eng. Chem. Fund. 14(4), 337–347) and of Orell (Orell, A., 2005, Experimental validation of a simple model for gas–liquid slug flow in horizontal pipes, Chem. Eng. Sci. 60, 1371–1381) so that the solubility effects can be taken into account.Indisponível

Influence of dry season on social wasp communities (Hymenoptera: Polistinae) in Deciduous Forest

 The seasonal deciduous forest, also known as dry forest, is characterized by the deciduity of tree species and two well-defined seasons which cause drastic changes in its physiognomy, and the seasonality of rainy periods directly impacts the forest’s biological communities. Social wasps (Vespidae: Polistinae) are well documented. However, some ecosystems in which they occur, such as the deciduous forest, are still subsampled. This study aimed to assess the response of social wasp communities to the dry season in a deciduous forest in the Mata Seca State Park, in the North of the state of Minas Gerais, Brazil. Insects were collected over 24 days divided into four field campaigns, each with six continuous days of collection (February, May, July, and November 2021), encompassing one campaign per season. All specimens were sacrificed and stored in 70% alcohol and later dry mounted for identification. The Kruskal-Wallis (KW) H test was performed to verify the difference between species richness, number of total colonies, and number of colonies of each tribe in relation to the collection station. In total, 131 colonies of eight species were located, particularly Polybia occidentalis (Olivier, 179), with 39 colonies, Polistes versicolor (Olivier, 1791), with 33, Mischocyttarus cassununga, with 21, and Protonectarina sylveirae (Saussure, 1854), with 13. Six species, five of which were from the Epiponini tribe, were collected in the four seasons. The responses of social wasps to the periods of drought in the deciduous forest vary with tribe. While Epiponini populations can keep colonies active in the dry season, Polistini cannot. Meanwhile, P. versicolor responds positively to the onset of the rainy season, increasing its population

Reducing scrap and improving an air conditioning pipe production line

30th International Conference on Flexible Automation and Intelligent Manufacturing (FAIM2021) -15-18 June 2021, Athens, GreeceThe automotive industry is considered one of the most demanding and competitive sectors in the global market. This increasingly implies having a stable and optimized production process, always with a view to continuous improvement. Therefore, it is very important to be aware of all the waste that is generated in all production and logistics operations and take action to reduce them. In this regard and considering the process of producing air conditioning pipes for the automotive industry, a high scrap value was detected mainly due to soldering process. Therefore, the entire production process is analyzed in order to identify the main causes behind the high scrap value. Several Lean and quality tools are used to reduce not only the amount of scrap but also to increase the line productivity. In order to face this challenge, after elaborating the action plan and corresponding implementation, the scrap value is reduced by 12% in general, and productivity increased by 29%, 55% and 22.5% in three different references produced by the same machine. Although this solution is a bit expensive, the corresponding payback is reduced, so it can easily be applied transversally to other similar machines allowing extremely interesting gains in the short term.Andresa Baptista acknowledges the financial support of CIDEM- Research Center of Mechanical Engineering, FCT –Portuguese Foundation for the Development of Science and Technology, Ministry of Science, Technology and Higher ducation, under the Project UID/EMS/0615/2019.info:eu-repo/semantics/publishedVersio

Hábitos alimenticios de la rana bromélicola Phyllodytes edelmoi Peixoto, Caramaschi & Freire, 2003 (Anura: Hylidae) del Estado de Alagoas, Noreste de Brasil

El género de hílidos Phyllodytes está compuesto por 12 especies distribuidas en el este de Brasil y conocidas por habitar estrictamente bromeliáceas. En este estudio se exploran los hábitos alimenticios de P. edelmoi y se testea la selectividad de las presas por la especie comparando las presas encontradas en los estómagos con la disponibilidad de presas en las bromelias. Nuestros resultados muestran que P. edelmoi consume grandes cantidades de hormigas a lo largo del año, por lo que podría considerarse una especie "especializada en hormigas". Este comportamiento alimenticio especializado podría ser considerado una sinapomorfia para el género Phyllodytes.The hylid frog genus Phyllodytes comprised 12 species distributed in eastern Brazil and knownto strictly inhabit inside bromeliads. In this study, we explore the feeding habits of P. edelmoiand test the prey selectivity of the species by comparing the prey items in the stomachs contentswith the availability of preys in bromeliads. Our results show that P. edelmoi consumes highamounts of ants along the year, and therefore it could be considered an ?ant specialist? species.This specialist feeding behaviour could be considered a synapomorphy of the genus Phyllodytes.Fil: Araujo-Vieira, Katyuscia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; ArgentinaFil: Ubiratan G. Silva. Universidade Federal de Alagoas; BrasilFil: Jhonatan Guedes dos Santos. Universidade Federal de Alagoas; BrasilFil: Thame G. Ferreira. Departamento de Ecologia E Biomonitoramento; BrasilFil: Gabriel O. Skuk. Universidade Federal de Alagoas; Brasi