The Autonomous University of Campeche is a Mexican public university based in the city of Campeche, Campeche, but with several campuses across the state. It was originally founded in 1965 as the Universidad del Sudeste .Its library holds over 18,000 volumes. Wikipedia.
Santana-Pineros A.M.,National Polytechnic Institute of Mexico |
Pech D.,Autonomous University of Campeche |
Vidal-Martinez V.M.,National Polytechnic Institute of Mexico
International Journal for Parasitology | Year: 2012
The goals of this paper were to determine whether the helminth communities of the blackcheek tonguefish, Symphurus plagiusa, exhibit a spatial structure and, if so, to determine the relative influence of selected environmental and spatial variables. The parasite communities of tonguefish and environmental data (e.g., temperature, salinity, oxygen) were sampled monthly over a network of 37 stations over 1. year (February 2006 to January 2007). Analysis of similarities (ANOSIM), non-metric multidimensional scaling (NMDS) and redundancy analysis (RDA) were used. Spatial variables were generated using the analysis of principal coordinates of neighbour matrices (PCNM) method. A total of 1,010 flatfishes and nine helminth taxa were collected. For the environmental variables, hierarchical cluster analyses produced groups of stations associated with the Yucatan dry, rainy and winter seasons. At the infracommunity level, there was no group formation as indicated by ANOSIM and NMDS nor association with environmental or spatial variables. At the component community level, there was significant group formation, and RDA analyses of core, satellite and all species produced significant associations with environmental variables. However, model fit improved substantially (from 17-52% to 49-83% of explained variance) when the spatial variables (variables generated with PCNM method) were added. Thus, the helminth component communities of S. plagiusa were affected by associated environmental variables and unknown ecological processes captured by the spatial variables acting at different spatial scales over time. In contrast, at the infracommunity level there was apparently a very fine spatial grain, where the numerical dominance of core species resulted in biased group formation. © 2012 Australian Society for Parasitology Inc.
Hernandez O.H.,Autonomous University of Campeche |
Vogel-Sprott M.,Autonomous University of Campeche |
Vogel-Sprott M.,University of Waterloo
Journal of Studies on Alcohol and Drugs | Year: 2010
Objective: This study uses a missing stimulus paradigm to investigate cognitive effects associated with moderate blood alcohol levels. Specifically, the rate of rise of the omitted stimulus potential (OSP), which is observed when an expected stimulus is omitted, as well as the peak latency of this potential correlate with cognitive premotor reaction time, and thus might involve similar cognitive processes. An acute dose of alcohol has been found to slow the premotor reaction time to a missing stimulus, but no research has tested alcohol effects on the OSP. Method: A dose of 0.8 g/kg alcohol or a placebo (0 g/kg) was administered in an across-subjects' design in two groups of 15 young men who were tested on a missing stimulus task before and again after alcohol. During a test, active trials required a response to the missing stimulus, and passive trials required no muscle action. Trials were counterbalanced in each group and obtained measures of premotor reaction time, motor reaction time, OSP onset and delay until muscle action, OSP amplitude, rate of rise, and peak latency. The pretreatment and posttreatment change in a measure assessed the alcohol effect. Results: Compared with placebo, alcohol slowed premotor reaction time, extended the delay of the OSP before muscle action, and slowed the OSP rate of rise and its peak latency. Conclusions: The similarity between alcohol effects on premotor reaction time and some parameters of the OSP supports the importance of examining how other environmental and pharmacological factors known to alter premotor reaction time might change components of the OSP and other types of event-related potentials.
Vidal-Martinez V.M.,CINVESTAV |
Pech D.,CINVESTAV |
Pech D.,Autonomous University of Campeche |
Sures B.,University of Duisburg - Essen |
And 2 more authors.
Trends in Parasitology | Year: 2010
This review assesses the usefulness of parasites as bioindicators of environmental impact. Relevant studies published in the past decade were compiled; factorial meta-analysis demonstrated significant effects and interactions between parasite levels and the presence and concentration of various pollutants and/or environmental stressors. These effects and interactions were also evident in subsets of studies that used different methods such as field surveys or experimental exposure. From this meta-analysis we conclude that parasites are useful bioindicators of environmental impact. Further, by examining aspects of study design, we put forward recommendations for the design of future studies to evaluate anthropogenic impact on host-parasite interactions and increase the efficiency of environmental monitoring programs. © 2009 Elsevier Ltd.
Casanova-Rosado J.F.,Autonomous University of Campeche
The West Indian medical journal | Year: 2013
To determine the prevalence of daily tooth brushing and evaluate some variables associated. A cross-sectional study was carried out in 320 schoolchildren six to nine years old in Campeche, Mexico. Information on sociodemographic and socio-economic variables, oral hygiene practices and attitudes were collected through a questionnaire. The frequency of tooth brushing was categorized as "0" = fewer than seven times/week, "1" = at least once a day. In the analysis, nonparametric tests were used. Mean age was 6.99 +/- 1.00 years, 52.5% were boys. The prevalence of daily tooth brushing was 81.6%. In bivariate analysis, the prevalence of tooth brushing was higher (p < 0.05) among the children of mothers with higher schooling (9.80 years vs 8.47 years, p < 0.05), and in younger children (84.6% in 6-7-year olds vs 71.2% in 8-9-year olds, p < 0.05). A slight, non-significant association (p < 0.10) was noted between the current frequency of tooth brushing and an earlier age when the child first started brushing with toothpaste. There were no statistically significant differences (p > 0.05) in the frequency of tooth brushing by gender or by the mother's attitude toward the oral health of her child. The prevalence of daily tooth brushing was high compared to other studies. Mother's maximum level of schooling (as an indicator of socio-economic position) was associated with higher frequency of tooth brushing. Maternal characteristics are associated with the oral health behaviour of their children.
Tapia A.,Autonomous University of Yucatán |
Acosta C.,Autonomous University of Yucatán |
Medina-Esquivel R.A.,Autonomous University of Yucatán |
Canto G.,Autonomous University of Campeche
Computational Materials Science | Year: 2011
The influence of potassium (K) on the hydrogen (H) adsorption on graphene (G) was studied by means of density functional theory with the generalized gradient approximation. The structural parameters, bonding and magnetic properties of one and two H atoms interacting with potassium doped graphene (H-K/G and 2H-K/G) are calculated for different energetically stable configurations. We found a charge transfer from K atom towards G even when the H atom pairs are adsorbed. This behavior is obtained for all the configurations studied here. The binding energy per H atom is greater in the most stable 2H-K/G arrangement than in both H-K/G and H/G systems. The present results suggest that the hydrogen atom binding energy on graphene layer could increase up to 82% due to the pre-adsorption of potassium. © 2011 Elsevier B.V. All rights reserved.
Blum-Dominguez S.,Autonomous University of Campeche
Revista médica del Instituto Mexicano del Seguro Social | Year: 2011
Trypanosoma cruzi was isolated from a 20 year old male with no evidence of antibodies against this parasite until 12 months after the isolation and with no electrocardiographic alterations. The isolated sample obtained was characterized as T. cruzi I through PCR mini-exon. It had been reported without serologic reactivity to T. cruzi. It is the first case with lack reactivity reported in Mexico.
Hernandez O.H.,Autonomous University of Campeche |
Vogel-Sprott M.,University of Waterloo
Journal of Psychophysiology | Year: 2010
A missing stimulus task requires an immediate response to the omission of a regular recurrent stimulus. The task evokes a subclass of event-related potential known as omitted stimulus potential (OSP), which reflects some cognitive processes such as expectancy. The behavioral response to a missing stimulus is referred to as omitted stimulus reaction time (RT). This total RT measure is known to include cognitive and motor components. The cognitive component (premotor RT) is measured by the time from the missing stimulus until the onset of motor action. The motor RT component is measured by the time from the onset of muscle action until the completion of the response. Previous research showed that RT is faster to auditory than to visual stimuli, and that the premotor of RT to a missing auditory stimulus is correlated with the duration of an OSP. Although this observation suggests that similar cognitive processes might underlie these two measures, no research has tested this possibility. If similar cognitive processes are involved in the premotor RT and OSP duration, these two measures should be correlated in visual and somatosensory modalities, and the premotor RT to missing auditory stimuli should be fastest. This hypothesis was tested in 17 young male volunteers who performed a missing stimulus task, who were presented with trains of auditory, visual, and somatosensory stimuli and the OSP and RT measures were recorded. The results showed that premotor RT and OSP duration were consistently related, and that both measures were shorter with respect to auditory stimuli than to visual or somatosensory stimuli. This provides the first evidence that the premotor RT is related to an attribute of the OSP in all three sensory modalities. © 2010 Federation of European Psychophysiology Societies.
Garcia-Ochoa E.,Autonomous University of Campeche |
Corvo F.,Autonomous University of Campeche |
Corvo F.,University of Habana
Electrochemistry Communications | Year: 2010
Chaos theory and the use of fractal geometry originated a new methodology to study EN signals obtaining new information on corrosion processes. A clear direct relationship is obtained between fractal analysis of EN time series and images. © 2010 Elsevier B.V. All rights reserved.
Velazquez M.A.,Autonomous University of Campeche
Animal Reproduction Science | Year: 2011
Since the 1990s nutritional supplements including protein, fatty acids, vitamins, and minerals have been used to try and improve the superovulatory response of embryo donors in cattle. However, the accumulated information indicates that nutritional supplementation with protein, fatty acids, or minerals does not increase the number of viable embryos from superovulated cattle. Most of the evidence has shown that vitamin supplementation may increase the mean production of transferable embryos, but only in cows, as a detrimental effect on embryo viability has been reported in young heifers. Nevertheless, vitamin supplementation seems to be effective only when compared with control cows displaying a poor mean embryo production (i.e. less than four viable embryos), questioning the economical significance of such approach. Detrimental effects on embryo development have been reported in superovulated cattle supplemented with protein or fatty acids as well. New approaches to investigate the role of nutritional supplementation on superovulatory outcome in cattle are suggested in the present review. Overall, the available evidence indicates that nutritional supplementation strategies tested are not an effective approach to enhance the superovulatory outcome of well-fed cattle donors. © 2011 Elsevier B.V.
Villeger S.,CNRS Biological Evolution and Diversity Laboratory |
Miranda J.R.,Autonomous University of Campeche |
Hernandez D.F.,Autonomous University of Campeche |
Mouillot D.,James Cook University |
Mouillot D.,Montpellier University
PLoS ONE | Year: 2012
The concept of β-diversity, defined as dissimilarity among communities, has been widely used to investigate biodiversity patterns and community assembly rules. However, in ecosystems with high taxonomic β-diversity, due to marked environmental gradients, the level of functional β-diversity among communities is largely overlooked while it may reveal processes shaping community structure. Here, decomposing biodiversity indices into α (local) and γ (regional) components, we estimated taxonomic and functional β-diversity among tropical estuarine fish communities, through space and time. We found extremely low functional β-diversity values among fish communities (&1.5%) despite high dissimilarity in species composition and species dominance. Additionally, in contrast to the high α and γ taxonomic diversities, α and γ functional diversities were very close to the minimal value. These patterns were caused by two dominant functional groups which maintained a similar functional structure over space and time, despite the strong dissimilarity in taxonomic structure along environmental gradients. Our findings suggest that taxonomic and functional β-diversity deserve to be quantified simultaneously since these two facets can show contrasting patterns and the differences can in turn shed light on community assembly rules. © 2012 Villéger et al.