This researcher was invited to give the talk at IWMEDIC 2016, IV International Workshop. Please, follow the link to see the video presentation uploaded (or to be uploaded soon) at the workshop official site: https://sciforum.net/conference/mol2net-02/iwmedic-04

The growing increase in the amount and type of nutrients in food created the necessity for a more efficient use in dietetics and nutrition. Flavonoids are exogenous dietary antioxidants and contribute to the total antioxidant capacity of the food. The current work aims to obtain optimal models to predict the total antioxidant properties of food by the ORAC method. A dataset based on the Database for the Flavonoid Content of Selected Foods and the Database for the Isoflavone Content of Selected Foods, was created. Different algorithms of artificial intelligence were applied, in particular Machine-Learning methods. They were employed using a R language. The performed study allowed to show the effectiveness of the models using structural-topologic features of Topological Substructural Molecular Design (TOPSMODE) in the databases. The proposed models can be considered, without overfitting, effective in predicting new values of ORAC, excepting the MultiLayer Perceptron (MLP) algorithm. The optimal model was obtained by the Random Forest (RF) algorithm, which presented the best R2 of the series (R2 = 0.9571313 for the training series and R2= 0.9247337 for the external prediction series).

The enzym phospholipase A2 (PLA2) catalyzes the conversion of membrane phospholipids in the inflammatory mediators, such as prostaglandins and leukotrienes. Because of this role, substances with inhibitory activity of PLA2 enzyme, has gained prominence in the scientific community like possible anti-inflammatory. Several studies have shown that phenolic compounds such as flavonoids, phenolic acids and other, has, among various biological activities, anti-inflammatory activity by inhibition of the enzyme PLA2. Based on this context, this study aimed to conduct a molecular docking study of various natural phenolic compounds and some of their derivatives forward to the enzyme PLA2. The crystallographic structure of PLA 2 was obtained from Target Database Protein Data Bank [PDB ID: 1KPM] and the ligands were obtained from PubChem Database. The docking was performed using the AutoDock 4.0 software. It was observed that among the phenolic compounds included in the study, those with better interaction with the enzyme were rosmarinic acid 3'-O-beta-glucoside, 4-nerolidylcatechol, rosmarinic acid methyl ester, quercetin 3-O-malonylglucoside, quercetin pentaacetate and rosmarinic acid, respectively. The present study provides a better understanding of the inhibition of PLA2 by phenolic compounds, which may contribute to the development of new anti-inflammatories.

Chagas disease is one of the most important in America  transmitted by Trypanosoma cruzi diseases with approximately 7 million people at risk,most of them from latin american. Due the non availability of an ideal drug or  treatment , development of an effective, and affordable vaccine could be a solution for control and prevention o f this disease. In this study, use an bioinformatic approach to predict posibles epitopes of the  candidates with help of  MHC-II Binding Predictor from IEDB,using the prection method of recommended in IEDB  and the set from Allele Class II from DbMHC and allelefrequencies.net with maximal population coverage, we analyze 10 sequence of surface protein expressed in trypanosoma cruzi in its three different stages present in the human body ,and keep the only ones with allotypes referring to the Latin American. A prediction of 70,000  epitopes per protein was obtained which were classified into three groups according to the shared epitopes, where the cruzipain belongs to a single group as it does not present similar epitopes with the other proteins. The first group contains the proteins Asp-3, Asp-2, Gp85, Gp90, Tc85, Sa85 with 17 shared epitopes and a population coverage of 87.89%. The second group Asp-3, Gp82, Gp83 with 31 shared epitopes and 87.89% population coverage. Because Cruzipain is not sharing any epitope, was selected the largest number of replicates contained in the same protein with a coverage above of 80 %.The selected epitopes are going to be synthesized to evaluate their potential as a possible vaccine against Trypanosoma cruzi.

With approximately 3 million annual deaths in the 1990s, tuberculosis remains a leading cause of mortality worldwide into the 21st century. It is estimated that one-third of the world population harbor a latent infection by the causative pathogen, mycobacterium tuberculosis according to the World Health Organization (WHO). In this sense, the mycobacterium tuberculosis remains one of the world’s most devastating pathogens. For this reason, is used the comparative modeling (homology modeling) to predict the (3-D) structure for the protein kinases Pkn D and Pkn H from mycobacterium tuberculosis. The homology modeling is a reliable computational tool to predict the three-dimensional (3-D) structure of proteins whose structures are unknown. The relationship between the sequence and the structure of the protein kinases is established using the evaluation of the respectives comparative models using WHAT_CHECK, ERRAT, VERIFY_3D, PROVE, CRYST1 record matches, Ramachandran Plot and WedMol Viewer programs.

Acknowledgements: A. M. B. Thanks to the Universidad de Talca (CBSM)) for the continuous support to this investigation and finally to the postdoctoral project N0 3150035 (FONDECYT, CHILE).

References 1 World Health Organization (WHO), www.who.org, Health topics (Tuberculosis), reviewed March 2014. 2 M. Cully. Redesigned antibiotic combats drug-resistant tuberculosis, Nature Reviews Drug Discovery, AOP, published online 21 March 2014; doi:10,1038/nrd4287. 3 R. E., Lee. Nature Medicine, 2014, 20, 152–158.

The emerging diseases in the different animal species require the necessary attention, to carry out actions that diminish their diffusion in animal populations. The aim of this study is to provide a current reference on coenurosis a wild rabbit (hare), and determinants of its presentation on animal health, which can put at risk man´s health. A sample of muscle tissue was evaluated and a hydatid cyst (3 x 6 cm) was obtained from a wild rabbit. The tissue was punctured, extracting transparent aqueous liquid discarding an abscess or hematoma. Content analysis showed the presence of many scolices, corresponding to coenuro Taenia serialis. In the histological preparation it was observed: muscle tissue, connective tissue fibroblasts and an inflammatory surrounding area composed of eosinophils and lymphocytes which in turn limited the parasite scolices. This finding representes an important condition to evaluate the natural environment of wild animals in the area, due to the risk of dissemination and contamination of plants and animals of the área, even though, may not be of of public health importance, unless meat of wild rabbits gets eaten.

Mathematical Modeling of the Optical response of photovoltaic cells

H. Morales¹ and D. Quesada²

¹ Miami Dade College, North Campus, Miami FL 33167

² School of Science, Technology, and Engineering Management, St. Thomas University, Miami Gardens, FL

 

With the perpetual depletion of fossil fuels, the rising of global temperatures as a result of CO₂ emissions, and the desire to have an independent source of renewable energy, photovoltaic cell (PVC) research has been on the rise. One of the main obstacles for the PVC industry is the efficiency of conversion of the systems currently in use. Traditional PVC employed single-band-gap semiconducting materials that used a very specific portion of the solar spectrum. The last fact explains the low conversion efficiency of such PV cells. Materials science and nanotechnology brought into the table multilayered tandem PV cells with different band-gaps per layer. This way, a wider portion of the solar spectrum has been utilized. Record efficiencies nowadays are around 40 % but only under laboratory conditions, whereas most commercial PVC is around 25 %. Quantum Dots (QD) represents another group of potential enhancers of conversion efficiencies. They might be prepared with different sizes and therefore multiple band-gaps might be obtained. Additionally, their nanostructured nature would permit to take advantage of Plasmonic effects operating at these scales. In this presentation the optical response of quantum dots (QD) composites is explored as a viable and potential new technology. Different configurations of dispersed QD within the host matrix are presented and compared with experimental realizations. The limitations of this approach are analyzed and future directions are envisioned.

Modeling the oscillating Belousov – Zhabotinsky chemical reaction

S. Centeno¹ and D. Quesada²

¹ Miami Dade College, North Campus, Miami FL

² School of Science, Technology, and Engineering Management, St. Thomas University, Miami Gardens, FL

 

Chemical reactions play a fundamental role in many processes in nature and life. At the same time, some of these reactions serve as a prototype for new technological applications ranging from biotechnology to quantum information. In this presentation, the kinetics of the well-known Belousov-Zhabotinsky oscillating reaction is studied. The choice of this particular reaction came from its similitude with circadian rhythms and the molecular clocks involved in the human response to microgravity conditions and the presence of electro-magnetic fields. The last facts are important for future deep space travels, as for example, the Mars program. Starting from first principles, chemical reactions often involve three components, diffusion, reaction and convection. The first two components are unaffected by the presence of external fields, while convection is strongly affected by temperature gradients, magnetic and electric fields. Additionally, when reactions occur in confined geometries, the interplay of all these factors lead to the formation of spatial self-organized structures, known as Turing instabilities. In the present communication, the chemical kinetics is modeled as a system on nonlinear differential equations following the scheme NKF. Critical points and conditions of stability are obtained, as well as the conditions leading to an oscillatory behavior. Since the study limited to the kinetics only, convection effects were neglected cause the influence of the magnetic field on the reaction could not be addressed. Even though a system of partial differential equations will include such effect, in this communication, a possible explanation for the Magnetic Field Effect (MFE) is advanced and is in qualitative agreement with experiments performed by a research team from the School of STEM at St. Thomas University.

Braess Paradox in Electrical Networks – When more might mean less

J. Rojas, A. Alonso and D. Quesada

School of Science, Technology and Engineering Management, St. Thomas University, Miami Gardens FL 33054

 

Electrical grids are part of the network of connections maintaining a city alive nowadays. Many times we see a limited amount of lines and poles, as well as, supportive local electrical transformer points (LETP). Most of these connections are wired in parallel in order to guarantee a sustainable flow of electricity plus being robust enough against failures. Why are we not making the system redundant and increasing the number of grid points and cabling? How the performance of a power grid network can be assessed from its connectivity pattern? In this presentation the Braess Paradox is investigated for several network configurations. Special interest is dedicated to the Wheatstone bridge and to those networks containing such configurations as part of their structural elements. The flow across the network as well as the overall resistance are computed and expressed in terms of network characteristics. In answering the first question, we hypothesized that despite of the economic cost of such approach there is a counter intuitive fact known as the Braess Paradox, which states that in a congested network, it may happen that adding a new path between destinations can increase the level of congestion. In transportation networks, the phenomenon results from the decisions of network participants who selfishly seek to optimize their own performance metrics. In an electric power distribution network, an analogous increase in congestion can arise as a consequence of Kirchhoff's laws. To address the second question, we also hypothesized that power grid performance might be assessed through a combination of indices characterizing networks and enabling quantify the easiness of connecting two distant points by walking the shortest path. The results obtained from executing these methods included: power grids can be mapped into networks of vertices (hubs) and edges (connecting lines); power grid networks can be studied through the Adjacency Matrix, Geodesic Paths, and Clustering coefficient; electrical networks behave similar to Road networks. In both cases, the addition of extra links (roads, connecting lines) yields to overloads and a detriment in performance. This fact is known as the Braess Paradox; for every network there is a critical value of edges above which, any addition does not introduce any improvement in performance; intelligent Dashboard can be implemented to control the performance of the power grid in parallel to the management windows.

Assessment of the impact of micrometeorological conditions on plants growth.

J. Jean – Jacques, Richard Aponte, and David Quesada

School of Science, Technology, and Engineering Management, St. Thomas University, Miami Gardens, FL 33054

 

Global climate changes and the acceleration of urbanization all over world constitute a serious problem for the health of soils, the microbiome inhabiting in them, and ultimately to the agriculture. Intensive agricultural practices have increased the use of industrial fertilizers, which in many cases remediate only temporarily and affect in the long term the soil biochemistry. In this communication, the assessment of the impact of the outdoor temperature and humidity around the organic garden located within the St. Thomas University forest is performed. An evaluation of the micrometeorological conditions using mobile sensors from Pasco and how they compare with meso-scale measurements using the automated weather station operated with Earth-Networks (Weatherbug) is done. Such studies are aimed at evaluating the impact of micrometeorological conditions of the effectiveness of artisanal soil in growing Okinawa spinach.