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Santiago de Queretaro, Mexico

The Autonomous University of Queretaro is a Mexican public university based in the city of Santiago de Querétaro, Querétaro, but with campuses around the state. The main campus is located in Cerro de las Campanas, but there are campuses is Amealco, Cadereyta, Jalpan, Juriquilla and San Juan del Río. Wikipedia.

Amezquita-Sanchez J.P.,Autonomous University of Queretaro | Adeli H.,Ohio State University
Archives of Computational Methods in Engineering | Year: 2016

Signal processing is the key component of any vibration-based structural health monitoring (SHM). The goal of signal processing is to extract subtle changes in the vibration signals in order to detect, locate and quantify the damage and its severity in the structure. This paper presents a state-of-the-art review of recent articles on signal processing techniques for vibration-based SHM. The focus is on civil structures including buildings and bridges. The paper also presents new signal processing techniques proposed in the past few years as potential candidates for future SHM research. The biggest challenge in realization of health monitoring of large real-life structures is automated detection of damage out of the huge amount of very noisy data collected from dozens of sensors on a daily, weekly, and monthly basis. The new methodologies for on-line SHM should handle noisy data effectively, and be accurate, scalable, portable, and efficient computationally. © 2014, CIMNE, Barcelona, Spain.

Yahia E.M.,Autonomous University of Queretaro | Mondragon-Jacobo C.,Instituto Nacional de Investigaciones Nucleares
Food Research International | Year: 2011

Cactus pear fruit (Opuntia) are harvested from various species of the genus Opuntia of the cactus family (Cactaceae), and are produced and consumed in several countries. We have characterized the nutritional content and antioxidant capacity (AC) of the fruit of ten cultivars/lines of distinct pulp colors. 'Camuesa' had the highest betalains, total carotenoids, ß-carotene, ascorbic acid, and was one of the highest in total phenolic compounds, but its AC did not demonstrate outstanding differences with some other cultivars/lines that were not as rich in these compounds. 'Roja Pelota' had high AC when measured with the DPPH assay, but had low total carotenoids, ß-carotene and total phenolic content. 'Reyna' had slightly low AC as measured by the FRAP assay, practically no betalains, and low vitamin C, tocopherols, ß-carotene, and total phenolic content. © 2011 Elsevier Ltd.

Munoz-Huerta R.F.,Autonomous University of Queretaro
Sensors (Basel, Switzerland) | Year: 2013

Nitrogen (N) plays a key role in the plant life cycle. It is the main plant mineral nutrient needed for chlorophyll production and other plant cell components (proteins, nucleic acids, amino acids). Crop yield is affected by plant N status. Thus, the optimization of nitrogen fertilization has become the object of intense research due to its environmental and economic impact. This article focuses on reviewing current methods and techniques used to determine plant N status. Kjeldahl digestion and Dumas combustion have been used as reference methods for N determination in plants, but they are destructive and time consuming. By using spectroradiometers, reflectometers, imagery from satellite sensors and digital cameras, optical properties have been measured to estimate N in plants, such as crop canopy reflectance, leaf transmittance, chlorophyll and polyphenol fluorescence. High correlation has been found between optical parameters and plant N status, and those techniques are not destructive. However, some drawbacks include chlorophyll saturation, atmospheric and soil interference, and the high cost of instruments. Electrical properties of plant tissue have been used to estimate quality in fruits, and water content in plants, as well as nutrient deficiency, which suggests that they have potential for use in plant N determination.

Garg N.,University of Illinois at Urbana - Champaign | Salazar-Ocampo L.M.A.,Autonomous University of Queretaro | Van Der Donk W.A.,University of Illinois at Urbana - Champaign
Proceedings of the National Academy of Sciences of the United States of America | Year: 2013

The biosynthesis of several classes of ribosomally synthesized and posttranslationally modified peptides involves dehydration of serine and threonine residues. For class I lantibiotics, thiopeptides, and goadsporin, this dehydration is catalyzed by lanthionine biosynthetic enzyme B (LanB) or LanB-like proteins. Although LanB proteins have been studied since 1992, in vitro reconstitution of their dehydration activity has been elusive. We show here the in vitro activity of the dehydratase involved in the biosynthesis of the food preservative nisin (NisB). In vitro, NisB dehydrated its substrate peptide NisA eight times in the presence of glutamate, ATP, Mg2+, and the ribosomal/membrane fraction of bacterial cell extract. Mutation of 23 highly conserved residues of NisB identified a number of amino acids that are essential for dehydration activity. In addition, these mutagenesis studies identified three mutants, R786A, R826A, and H961A, that result in multiple glutamylations of the NisA substrate. Glutamylation was observed during both Escherichia coli coexpression of NisA with these mutants and in vitro assays. Treatment of the glutamylated substrate with WT NisB results in dehydrated NisA, suggesting that the glutamylated peptide is an intermediate in dehydration. Collectively, these studies suggest that dehydration involves glutamylation of the side chains of Ser and Thr followed by elimination. The latter step has precedent in the virginiamycin resistance protein virginiamycin B lyase. These studies will facilitate investigation of other LanB proteins involved in the biosynthesis of lantibiotics, thiopeptides, and goadsporin.

Garcia O.P.,Autonomous University of Queretaro
Proceedings of the Nutrition Society | Year: 2012

Obesity has been associated with low-grade systemic inflammation and with micronutrient deficiencies. Obese individuals have been found to have lower vitamin A levels and lower vitamin A intake compared with normal-weight individuals. Vitamin A plays a major role in the immune function, including innate immunity, cell-mediated immunity and humoral antibody immunity. It has also been recognised recently that vitamin A has important regulatory functions. Vitamin A status has an important effect on the chronic inflammatory response. Vitamin A deficiency increases a T-helper type 1 (Th1) response, elevates levels of pro-inflammatory cytokines, increases the expression of leptin, resistin and uncoupling proteins (UCP) and promotes adipogenesis. The effect of vitamin A deficiency on obesity might be increasing the risk of fat deposition and also the risk of chronic inflammation associated with obesity. Supplementation with vitamin A in vitro and in animal models has been found to reduce concentrations of adipocytokines, such as leptin and resistin. In conclusion, vitamin A deficiency increases a Th1 response in the presence of obesity and thus, increases the inflammatory process involved in chronic inflammation and fat deposition. The metabolism of leptin and other adipocytokines may play a critical role in the effect of vitamin A deficiency in the inflammatory response observed in obesity. © 2012 The Author.

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