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Monterrey, Mexico

The Monterrey Institute of Technology and Higher Education commonly shortened as Monterrey Institute of Technology or Monterrey Tech is one of the largest private, nonsectarian and coeducational multi-campus universities in Latin America with over 90,000 students at the high school, undergraduate, and postgraduate levels.Based in Monterrey, Mexico, the Institute has 31 campuses in 25 cities throughout the country and is known for becoming the first university ever connected to the Internet in Latin America and the Spanish-speaking world, having one of the top graduate business schools in the region and being one of the leaders in patent applications among Mexican universities. Wikipedia.

Cornaton F.J.,Monterrey Institute of Technology
Water Resources Research | Year: 2012

Environmental fluid circulations are very often characterized by analyzing the fate and behavior of natural and anthropogenic tracers. Among these tracers, age is taken as an ideal tracer which can yield interesting diagnoses, as for example the characterization of the mixing and renewal of water masses, of the fate and mixing of contaminants, or the calibration of hydrodispersive parameters used by numerical models. Such diagnoses are of great interest in atmospheric and ocean circulation sciences, as well in surface and subsurface hydrology. The temporal evolution of groundwater age and its frequency distributions can display important changes as flow regimes vary due to natural change in climate and hydrologic conditions and/or human induced pressures on the resource to satisfy the water demand. Groundwater age being nowadays frequently used to investigate reservoir properties and recharge conditions, special attention needs to be put on the way this property is characterized, would it be using isotopic methods or mathematical modeling. Steady state age frequency distributions can be modeled using standard numerical techniques since the general balance equation describing age transport under steady state flow conditions is exactly equivalent to a standard advection-dispersion equation. The time-dependent problem is however described by an extended transport operator that incorporates an additional coordinate for water age. The consequence is that numerical solutions can hardly be achieved, especially for real 3-D applications over large time periods of interest. A novel algorithm for solving the age distribution problem under time-varying flow regimes is presented and, for some specific configurations, extended to the problem of generalized component exposure time. The algorithm combines the Laplace transform technique applied to the age (or exposure time) coordinate with standard time-marching schemes. The method is validated and illustrated using analytical and numerical solutions considering 1-D, 2-D, and 3-D theoretical groundwater flow domains. Copyright 2012 by the American Geophysical Union.

Cuello-Garcia C.A.,Monterrey Institute of Technology
Cochrane database of systematic reviews (Online) | Year: 2013

Bacillus Calmette-Guerín (BCG) is a live attenuated vaccine to prevent tuberculosis, routinely administered at birth as part of the World Health Organization global expanded immunisation programme. Given intradermally, it can cause adverse reactions, including local, regional, distant and disseminated manifestations that may cause parental distress. Rarely, it can cause serious illness and even death. Among those patients with immunocompromised conditions, such as the human immunodeficiency virus (HIV) infection, the complication rate is even higher. To assess the effects of different interventions for treating BCG-induced disease in children. The following databases were searched: the Cochrane Infectious Diseases Group Specialized Register and Cochrane Central Register of Controlled Trials (CENTRAL), published in The Cochrane Library (The Cochrane Library 2012, Issue 4); MEDLINE (1966 to November 2012); EMBASE (1947 to November 2012); and LILACS (1980 to November 2012). The metaRegister of Controlled Trials (mRCT) and the WHO trials search portal. Conference proceedings for relevant abstracts and experts were also contacted to identify studies. No language restrictions were applied. Randomized controlled trials (RCTs) comparing any medical or surgical treatment modality for BCG-induced disease in children. Two authors independently evaluated titles, applied inclusion criteria, and assessed the risk of bias of studies. The primary outcomes were the failure rate of therapies for all types of BCG vaccine-induced complications and the time to resolution of illness measured in months. The secondary outcomes were death from BCG vaccine-induced disease and the all-cause mortality. Risk ratios (RRs) were used as measure of effect for dichotomous outcomes and mean differences for continuous outcomes. Five RCTs analysing 341 children addressed the primary outcomes and were included. Four arms compared oral antibiotics to no intervention or placebo, one arm evaluated needle aspiration compared to no intervention, and another evaluated the use of locally instilled isoniazid versus oral erythromycin.Two small studies evaluated oral isoniazid; we are uncertain of whether this intervention has an effect on clinical failure (RR 1.48; 95% Confidence Interval (CI) 0.79 to 2.78; 54 participants, two studies, very low quality evidence). Similarly, for oral erythromycin, we are uncertain if there is an effect (clinical failure RR 1.03; 95% CI 0.70 to 1.53; 148 participants, three studies, very low quality evidence), and for oral isoniazid plus rifampicin (clinical failure, RR 1.20; 95% CI 0.51 to 2.83; 35 participants, one study, very low quality evidence).In patients with lymphadenitis abscess, needle aspiration may reduce clinically persistent BCG-induced disease at 6 to 9 months of follow-up (RR 0.13; 95% CI 0.03 to 0.55; 77 participants, one study, low quality evidence). In another study of patients with the same condition, aspiration plus local instillation of isoniazid reduces time to clinical cure compared to aspiration plus oral erythromycin (mean difference 1.49 months less; 95% CI 0.82 to 2.15 less; 27 participants, one study).No RCTs of HIV-infected infants with a BCG-induced disease evaluated the use of antibiotics or other therapies for reducing the rate of clinical failure or the time to clinical resolution. No data on mortality secondary to the interventions for treating BCG-induced disease were reported. It is unclear if oral antibiotics (isoniazid, erythromycin, or a combination of isoniazid plus rifampicin) are effective for the resolution of BCG-induced disease. Most non-suppurated lymphadenitis will resolve without treatment in 4 to 6 months. Patients with lymphadenitis abscess might benefit from needle aspiration and possibly local instillation of isoniazid could shorten recovery time. Included studies were generally small and could be better conducted. Further research should evaluate the use of needle aspiration and local instillation of isoniazid in fluctuant nodes. Therapeutic and preventive measures in HIV-infected infants could be important given the higher risk of negative outcomes in this group.

Christians J.A.,University of Notre Dame | Miranda Herrera P.A.,University of Notre Dame | Miranda Herrera P.A.,Monterrey Institute of Technology | Kamat P.V.,University of Notre Dame
Journal of the American Chemical Society | Year: 2015

Humidity has been an important factor, in both negative and positive ways, in the development of perovskite solar cells and will prove critical in the push to commercialize this exciting new photovoltaic technology. The interaction between CH3NH3PbI3 and H2O vapor is investigated by characterizing the ground-state and excited-state optical absorption properties and probing morphology and crystal structure. These undertakings reveal that H2O exposure does not simply cause CH3NH3PbI3 to revert to PbI2. It is shown that, in the dark, H2O is able to complex with the perovskite, forming a hydrate product similar to (CH3NH3)4PbI6·2H2O. This causes a decrease in absorption across the visible region of the spectrum and a distinct change in the crystal structure of the material. Femtosecond transient absorption spectroscopic measurements show the effect that humidity has on the ultrafast excited state dynamics of CH3NH3PbI3. More importantly, the deleterious effects of humidity on complete solar cells, specifically on photovoltaic efficiency and stability, are explored in the light of these spectroscopic understandings. © 2015 American Chemical Society.

Venegas-Andraca S.E.,Monterrey Institute of Technology
Quantum Information Processing | Year: 2012

Quantum walks, the quantum mechanical counterpart of classical random walks, is an advanced tool for building quantum algorithms that has been recently shown to constitute a universal model of quantum computation. Quantum walks is now a solid field of research of quantum computation full of exciting open problems for physicists, computer scientists and engineers. In this paper we review theoretical advances on the foundations of both discrete- and continuous-time quantum walks, together with the role that randomness plays in quantum walks, the connections between the mathematical models of coined discrete quantum walks and continuous quantum walks, the quantumness of quantum walks, a summary of papers published on discrete quantum walks and entanglement as well as a succinct review of experimental proposals and realizations of discrete-time quantum walks. Furthermore, we have reviewed several algorithms based on both discrete- and continuous-time quantum walks as well as a most important result: the computational universality of both continuous- and discrete-time quantum walks. © Springer Science+Business Media, LLC 2012.

Winkler R.,Monterrey Institute of Technology
Rapid Communications in Mass Spectrometry | Year: 2010

Electrospray ionization (ESI) ion trap mass spectrometers with relatively low resolution are frequently used for the analysis of natural products and peptides. Although ESI spectra of multiply charged protein molecules also can be measured on this type of devices, only average spectra are produced for the majority of naturally occurring proteins. Evaluating such ESI protein spectra would provide valuable information about the native state of investigated proteins. However, no suitable and freely available software could be found which allows the charge state determination and molecular weight calculation of single proteins from average ESI-MS data. Therefore, an algorithm based on standard deviation optimization (scatter minimization) was implemented for the analysis of protein ESI-MS data. The resulting software ESIprot was tested with ESI-MS data of six intact reference proteins between 12.4 and 66.7kDa. In all cases, the correct charge states could be determined. The obtained absolute mass errors were in a range between -0.2 and 1.2Da, the relative errors below 30ppm. The possible mass accuracy allows for valid conclusions about the actual condition of proteins. Moreover, the ESIprot algorithm demonstrates an extraordinary robustness and allows spectral interpretation from as little as two peaks, given sufficient quality of the provided m/z data, without the necessity for peak intensity data. ESIprot is independent from the raw data format and the computer platform, making it a versatile tool for mass spectrometrists. The program code was released under the open-source GPLv3 license to support future developments of mass spectrometry software. © 2010 John Wiley & Sons, Ltd.

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