State Of Yucatan Research Articles

Presence of Rickettsia Species in a Marginalized Area of Yucatan, Mexico.

In the state of Yucatan, Mexico, rickettsiosis has become a common vector-borne disease in the general population. Ectoparasite species such as Rhipicephalus sanguineus and Amblyomma mixtum have been identified as Rickettsia vectors in Yucatan by studies focused on the wild animal population in rural areas. There have been studies that have tried to determine the presence of Rickettsia species in ectoparasites collected in Yucatan, but these studies did not include marginalized areas, where living in close contact with domestic and peridomestic animals that carry ectoparasites is a high-risk factor for acquiring rickettsial infection or many other vector-borne diseases. We evaluated the vector diversity and the presence of Rickettsia species presence in the ectoparasite population that parasitizes domestic animals in a marginalized rural town of Yucatan, Mexico; we also evaluated the seroprevalence of rickettsial antibodies in the human population of this town in order to determine the prevalence of rickettsial infection. A total of 437 ectoparasites were collected from the study area. The tick specimens collected belonged to the species Rhipicephalus sanguineus (n=380, 49 positive), Amblyomma mixtum (n=3, 0 positive), Ixodes affinis (n=4, 0 positive), Ctenocephalides felis (n=33, 0 positive), and Trichodectes canis (n=17, 0 positive). Conventional polymerase chain reaction and sequencing were used to identify the DNA of Rickettsia. Six out of 354 (1.8%) serum samples were positive for antibody to R. typhi. The combination of low antibody titers and the presence of Rickettsia species infecting ectoparasite species found in the study area requires eco-epidemiological studies and the identification of potentially protective practices or habits.

First Record of Invasive Mosquito Aedes albopictus in Tabasco and Yucatan, Mexico.

The invasive mosquito Aedes albopictus is currently distributed in most of the southern Mexican region. Since the species was first recorded in the state of Tamaulipas, in northeastern Mexico in 1988, it has expanded its distribution throughout the Sierra Madre Oriental and Gulf of Mexico to the Neotropical region of the country. Currently the species occurs in the states of Tamaulipas, Coahuila, Nuevo Leon, Veracruz, Chiapas, Morelos, Quintana Roo, Sinaloa, San Luis Potosi, and Hidalgo. This is the first report of the mosquito in the states of Tabasco and Yucatan and the confirmation of its presence in Quintana Roo state. Aedes albopictus has been incriminated as a secondary vector of diseases such as those caused by dengue, chikungunya, and Zika viruses, which have caused epidemic outbreaks in most tropical and subtropical regions of Mexico; therefore, surveillance for the detection of Ae. albopictus is paramount so that targeted control strategies can be implemented for its control throughout Mexico.

Brominated Flame Retardants in Sediments of Four Coastal Lagoons of Yucatan, Mexico.

We examined the sediments of four coastal lagoons (Ria Lagartos, Bocas de Dzilam, Laguna de Chelem and Ria Celestun) from the state of Yucatan, Mexico, for three widely used commercial polybrominated diphenyl ethers formulations (penta-, octa- and deca-BDE). The most commonly found congeners in all four lagoons were BDEs 47, 99 and 100 (all in the penta-BDE formulation) and BDE209 (deca-BDE formulation). The greatest variety and highest concentrations of brominated flame retardants were found in Ria Lagartos, which also showed the highest BDE 100 concentration (24.129ng/g). Hexabromocyclododecane was found in all lagoons, but at lower concentrations than those of the various polybrominated diphenyl ethers. Dispersal routes of these compounds are discussed, such as a ring of sinkholes (cenotes) adjacent to the lagoons. Moreover, electronic waste is a serious problem because municipal landfills have been the primary disposal method for these wastes and therefore represent a reservoir of brominated fire retardants.

Presence of DDT and Lindane in a Karstic Groundwater Aquifer in Yucatan, Mexico

AbstractPollution caused by pesticides is becoming relevant because of their harmful environmental effects. The persistence, bioaccumulation and toxicity of some organochloride pesticides have resulted in their restricted use since 1970 and a requirement to monitor them in many countries. Pesticides have endocrine, immunological, reproductive and carcinogenic effects in both humans and animals. The facilitated infiltration of substances results in the pollution of hydric underground resources in karstic limestone such as that found in the state of Yucatan. Observing the north occidental region of the state of Yucatan is particularly important as it is characterized by agricultural activities (wide use of pesticides), significant human settlements and underground water flows oriented towards the north coast. In this study, the underground water quality of a karstic aquifer was evaluated by quantifying the presence of organochlorine pesticides in 29 wells located throughout the Mérida‐Progreso transect, Yucatan, Mexico. The presence of DDT, lindane and their metabolites was detected at concentrations above the permissible limits stated by Mexican regulatory standards (NOM‐127‐SSA1‐1994 2010) in the majority of wells studied. Continuous monitoring of the underground hydric resources in this region is therefore essential to raising awareness of pollution risks and the vulnerability of the coastal north to the contamination of the underground water flows.

Environmental Exposure of Children to Toxic Trace Elements (Hg, Cr, As) in an Urban Area of Yucatan, Mexico: Water, Blood, and Urine Levels.

Merida is the largest urban center in the Mexican State of Yucatan. Here domestic sewage is deposited in poorly built septic tanks and is not adequately treated. Because of contamination from such waste, water from the top 20m of the aquifer is unsuitable for human consumption. Given this situation and because children are highly vulnerable to environmental pollution, including exposure to toxic trace elements, this study focused on evaluating the exposure of children to arsenic (As), chromium (Cr), and mercury (Hg) in water. It also evaluated the relationship between the levels of these elements in water and their concentrations in urine and blood. Among the 33 children monitored in the study, arsenic surpassed WHO limits for blood in 37% of the cases, which could result from the ingestion of poultry contaminated with organoarsenic compounds. In the case of WHO limits for Mercury, 65% of the water samples analyzed, 28% of urine samples, and 12% of blood samples exceeded them. Mercury exposure was correlated with biological sex, some lifestyle factors, and the zone in Merida in which children live. These data suggest that the levels of some toxic metals in children may be affected by water source, socioeconomic factors, and individual behavior.

Prevalence of obesity and diabetes in the socioeconomic transition of rural Mayas of Yucatan from 1962 to 2000

ABSTRACT Background: The Mayas of the State of Yucatan in Mexico are the only aboriginal group with obesity and diabetes data before 1997. Objective: To analyze socioeconomic trends associated with the increase in obesity and diabetes seen in rural Yucatan from 1962 to 2000. Methods: Body weight, height and venous Fasting Blood Glucose (FBG) were measured in 263 rural Maya adults participating in a 2000 nutrition survey. Results: Diabetes (FBG > 125 mg/dL) and obesity (BMI ≥ 30 kg/m2) were 10.6% and 35.7%, respectively. These results contrast with those of a 1962 survey where diabetic prevalence was 2.3% and 0% in women and men respectively, with widespread adult pellagra and malnutrition. An important socioeconomic transition that took place in Yucatan during this lapse appeared to be associated to the obesity and diabetes increase. Conclusions: Rural Yucatan evolved from malnutrition conditions to high prevalence of obesity and diabetes in less than 40 years. This change was associated with the transition from an agroindustry-based economy, characterized by high-energy expenditure and low protein intake, to lower energy requirements of a Government-subsidized economy with larger food supply.

Purpose in Life and Professional Life Project in College Students

The objective of this study was to determine the relation between the level of purpose in life and the level of dominion obtained by the students in the construction of a professional life project; after the implementation of a course based on the Logotherapy approach, which lasted a total of 64 hours. The areas worked were self-discovery, unicity, freedom, responsibility and self-transcendence. Logotherapeutic techniques of Socratic dialogue, role playing and cinema-logotherapy were used. The objective was to redirect the work carried out with students of the Bachelor Degree in Education at a Public University in the State of Yucatan, so that they could be aware of themselves, discover their potential and find their mission in life to give meaning to their chosen profession. The design of the study was pre-experimental, pretest-post-test, without control group; and the meaning of life test was administered to identify the level of Purpose in Life of the students. A rubric was used to evaluate the professional life projects that were developed by the students. The results showed that there is no relation between the level of Purpose in Life and the development of the professional life project, since the strengthening of the Purpose in Life did not necessarily imply the development of a professional life project in accordance with the potentials of the students, neither they managed to establish clear goals and specific commitments to achieve their goals.

Life-cycle assessment of bioethanol production from sweet sorghum stalks cultivated in the state of Yucatan, Mexico

Bioethanol is being promoted in Mexico to be used in a blend with gasoline. On the north of the Yucatan peninsula, bioethanol could be produced from sweet sorghum, as it can grow efficiently on this land; it can be harvested 2–3 times in a year and possesses a better agronomical stability than sugarcane with low nitrogen requirements and high productivity. In this work , the potential environmental impacts and energy efficiency of bioethanol production from sweet sorghum were evaluated using life-cycle assessment. Four scenarios were evaluated: scenario PI considered only bioethanol production from the stalk juice; scenarios PII and PIII added cogeneration from the dry-stalk biomass in single and combined cycle, respectively. Scenario PIV considered bioethanol production from both stalk juice and dry-stalk biomass. Scenario PI demanded more fossil energy than what was generated as bioethanol, while scenarios PII and PIII were fossil energy independent. Scenario PIII showed the higher net energy ratio (1.89) and a better environmental performance in all CML-IA baseline impact categories. In terms of global warming potential, the scenario PIII showed a mitigation potential of 16% with respect to the fossil reference. In the categories where the sweet sorghum scenarios represented larger emissions than the fossil reference, it was due mainly to the use of fertilizers and the conventional energy consumption in the various processing steps of the biomass. Scenario PIV showed the highest energy demand and worst environmental performance due to large demands of energy and chemicals in the bagasse pretreatment step.

Application of Artificial Neural Networks for Dengue Fever Outbreak Predictions in the Northwest Coast of Yucatan, Mexico and San Juan, Puerto Rico.

Modelling dengue fever in endemic areas is important to mitigate and improve vector-borne disease control to reduce outbreaks. This study applied artificial neural networks (ANNs) to predict dengue fever outbreak occurrences in San Juan, Puerto Rico (USA), and in several coastal municipalities of the state of Yucatan, Mexico, based on specific thresholds. The models were trained with 19 years of dengue fever data for Puerto Rico and six years for Mexico. Environmental and demographic data included in the predictive models were sea surface temperature (SST), precipitation, air temperature (i.e., minimum, maximum, and average), humidity, previous dengue cases, and population size. Two models were applied for each study area. One predicted dengue incidence rates based on population at risk (i.e., numbers of people younger than 24 years), and the other on the size of the vulnerable population (i.e., number of people younger than five years and older than 65 years). The predictive power was above 70% for all four model runs. The ANNs were able to successfully model dengue fever outbreak occurrences in both study areas. The variables with the most influence on predicting dengue fever outbreak occurrences for San Juan, Puerto Rico, included population size, previous dengue cases, maximum air temperature, and date. In Yucatan, Mexico, the most important variables were population size, previous dengue cases, minimum air temperature, and date. These models have predictive skills and should help dengue fever mitigation and management to aid specific population segments in the Caribbean region and around the Gulf of Mexico.

Evaluation of the Strength of Limestone After Long-Term Weathering Under Natural Conditions

We study the sorption properties, porosity and density of the limestone rocks from the State of Yucatan in Mexico (Campeche). The investigations are needed to save historical heritage, namely, it is necessary to optimize the technology of injection of polymer materials in order to restore the strength and integrity of the colonial and pre-Spanish buildings made of limestone.

Actividades de tiempo libre y el bienestar espiritual

This research analyzes the factorial structure of the Leisure Coping Belief Scale (LCBS-M) in a simple of 202 adults belonging to the states of Nuevo Leon and Yucatan, Mexico, with an average age of 28 years (DE = 9.57). Its convergent validity was obtained through the Spirituality and Leisure Coping Belief Scales (LCBS-M) about their leisure activities. Both scales, the Spirituality and the LCBS-M, gave evidence of convergent validity. Following an analysis of competition of models, a factorial structure similar to the original model was obtained. This model includes the same three dimensions and 20 items; two items less than the original model. The results revealed that the Mexican adaptation maintained an adequate degree of reliability on a general scale.

Changes in the incidence of intestinal giardiosis in Mexican population during five years (2011-2015).

Giardiosis is a parasitic disease caused by the protozoan Giardia intestinalis, which is distributed worldwide. Most of the data on the prevalence of giardiosis in Mexico comes from research, but it is also necessary to study the data provided by the Mexican Health Ministry and issued by the General Directorate of Epidemiology. The aim of this work was analyse the national surveillance data for human giardiosis in order to update the epidemiological data of this disease in Mexico. A retrospective observational analysis of giardiosis (from January 2011 to December 2015) was performed in the annual reports emitted by the GDE in Mexico. The cases were classified by year, state, age group, gender and seasons of the year. During the period of 2011-2015, a reduction of 38.51% was observed in the total number of new cases of giardiosis reported in the whole country The states of Sinaloa, Yucatan, and Chiapas presented the highest number of new cases reported during the analysed period. Giardiosis rates were always higher among women in all age groups, but the maximum incidence was observed in both sexes in the age group of 1-4 years old (the most susceptible group). On the other hand, the number of cases increased dramatically in southern states during warmer months. Giardiosis is influenced by ambient temperature changes along the year, although this study suggests that tends to decrease in all the analysed states and could be related to the overall improvement of hygienic practices within the Mexican population.

School Violence in Contexts of High Social Marginalization and Ethnic Population of Yucatan, Mexico

The objective of this work was to determine the magnitude and frequency of school violence in the eastern part of the state of Yucatan, Mexico, which is populated primarily by Maya-speakers and also by communities of high social marginalization, factors associated with adolescence, and the condition of gender, by contexts that have been poorly documented in the face of the phenomenon of violence in secondary schools. Quantitative study through a self-applied survey of 1432 high school students is possible to conclude that the conditions of gender, social and ethnic marginalization are elements that come together in vulnerabilities to present violence in social contexts with a strong magnitude. The students show similar proportions of violence in to teachers (93%), a significant difference in women than the recorded by men (p = 0.000), with a greater number of cases in moderate and severe intensity. Peer violence is manifested a statistically significant difference by men and women, in which women reflect a greater intensity, with a higher number of cases in violence of moderate and severe intensity (p = 0.000).

Dinámica de adopción de buenas prácticas de producción de miel en la península de Yucatán, México

Los objetivos fueron analizar los cambios en la adopción de buenas prácticas de producción de miel (BPPM) en productores apícolas de la Península de Yucatán, México, antes y después de haber recibido asesoría técnica y capacitación; así como la identificación de factores que inciden en la adopción de dichas prácticas. Considerando 31 BPPM agrupadas en siete categorías, se calculó el índice de adopción de BPPM (InABPPM). Se analizó información de 8,074 apicultores en dos momentos (línea base y línea final), para los estados de Yucatán (n= 3,840), Campeche (n= 3,525) y Quintana Roo (n= 709). Los apicultores se clasificaron de acuerdo al número de colmenas que poseían en: pequeños (1-22, 24 %), medianos (23-35,27 %) y grandes (36-400, 49 %). El InABPPM global presentó un incremento significativo (P<0.01) de 16.8 % en un periodo de ocho meses. Además, se encontraron diferencias significativas (P<0.01) en las categorías de ubicación e instalación del apiario, sanidad apícola, cosecha, personal en campo y programa de limpieza e higiene. No se encontraron diferencias significativas para las categorías de alimentación artificial y materiales para la protección y ahumado de la colmena (P>0.05). Este estudio destaca la importancia de programas para la gestión y difusión de BPPM, con la finalidad de impulsar la actividad apícola y acceder al mercado internacional cumpliendo con las normas de calidad requeridas. Los resultados sugieren impulsar la adopción de las BPPM de proceso, y posteriormente orientar la inversión de los apoyos púbicos en aquellos apiarios con mejor desempeño en cuanto al incremento en sus niveles de adopción.

Competitiveness model for the bovine livestock industry in Mexico

PurposeThe purpose of this paper is to develop a model of competitiveness for the bovine livestock industry in the state of Yucatan, Mexico, by considering factors such as innovation, marketing, and finance (Perea and Rivas, 2008).Design/methodology/approachOwners of 30 cattle ranches were included in the state surveys, with each ranch having at least 1,000 head of cattle. The study was quantitative, and used the method of thresholds (Pengfei, 2006), stratification of Dalenius and Hodges (1959), Pearson’s correlation, and multivariate regression analysis.FindingsThe level of competitiveness in the livestock industry in Yucatan, and a model for its determination obtained as results reflect a similar importance for the three factors, with marketing and innovation being considered relatively more important.Research limitations/implicationsIt is worth nothing the context in which this information can be applies.Originality/valueThis study is unique because the results obtained have important practical implications for the sector. The livestock industry in Yucatan represents one of the main strategic activities of the state, and now faces serious problems of competitiveness.

The relationship between forest fragmentation and the potential geographical distribution of psittacids (Psittaciformes: Psittacidae) in the Yucatan Peninsula, Mexico

Parrots are a seriously threatened group because of the illegal pet trade, their habitat fragmentation and the destruction of tropical forests. This study aimed to determine the relationship between forest fragmentation and the geographic potential distribution of parrot species in the Yucatan Peninsula, Mexico. The research was carried out in the Mexican portion of the Yucatan Peninsula Biotic region, which includes the states of Campeche, Quintana Roo and Yucatan. We worked with the eight species of psittacids that inhabit the selected areas: Eupsittula nana, Amazona albifrons, Amazona xantholora, Amazona autumnalis, Pionus senilis, Pyrilia haematotis, Amazona oratrix and Amazona farinosa. For these species, we used the potential geographical distribution maps that were obtained through the Maximum Entropy algorithm, published in 2014. To measure the levels of forest fragmentation in the Peninsula, we employed the land use and vegetation maps from series IV (2007-2010) of the National Institute of Statistics and Geography. We calculated different landscape metrics at 100 sites randomly distributed within the predicted presence and absence areas for the species. Multivariate methods were used to shorten dimensionality in the analysis, as well as to explore the observed patterns. We did not find any pattern regarding the number of variables that contribute to the logistic regression models (LR) and the size of the parrots’ potential geographical distribution area within the Peninsula. For Pyrilia haematotis and Amazona oratrix, the fragmentation variables used did not seem to have any relationship with their potential geographical distribution in the Peninsula (intersection, Pr < 0.0001). Only for Eupsittula nana, Amazona xantholora and Pionus senilis, we found that the mean patch edge, the mean shape index and the mean perimeter-area ratio were important to determine their potential distribution patterns, respectively; and, in general, the variables indicated the preferences of these parrots to occupy larger habitat patches. Parrots must be given a special care and protection within the states of Campeche and Quintana Roo, since there are areas with high parrot diversity and are importantly affected by human activities. The best recommendation for managers and users of protected areas within the Yucatan Peninsula is that extensive areas of forest should be maintained in order to guarantee the suvival of psittacid populations.

Preparación de alumnos de licenciatura para el éxito en su carrera profesional a través de la elaboración e implementación de estudios de caso en contextos reales de trabajo

The objective of this study was to test the effectiveness of a procedure to train undergraduate students to write and implement case studies for improving their learning experiences, adapt to the labor environment and be better prepared for career success. Method . Undergraduate students in social service internships at the Higher State Auditing Office in the states of Yucatan, Campeche and Q. Roo, in the Southeast of Mexico, under the guidance of Government Auditors, designed case studies to be implemented with their classmates following the procedure studied in this document, prepared by the author of this research. Results. Results showed that after this experience, implementer students were more motivated for learning, more interested in case studies, more confident at working with others and were satisfied with learning. This was compared to the learning through traditional methods, according to their perception. Conclusion. This case study procedure is effective for preparing students for improving their technical and socio-emotional competencies in their preparation for career success, but also a professional development opportunity for the Auditors. Learning to write and implement cases help learning and adaptation to work environment. It is learning how to learn and be prepared for career success through experiences such as this in real job contexts.

Bone copper content in sheep in relation to their drinking water source

The aim was to estimate the Cu content in the bones of grazing sheep and relate it to their drinking water. Cu was analyzed by taking bone biopsies. Samples from the twelfth rib were taken in 107 animals and water samples were collected from forty wells in the same farms located in four agroecological areas in Yucatan state, Mexico. Cu was analyzed by atomic absorption. Data were analyzed using the least squares method. Cu content in bone tissue was: weaned 0.66 a ; Females prior to rst gestation 0.57 b and ewes 0.64 a mg/kg -1 . Normal content in bone is 2-3 mg/kg -1 , indicating a de ciency in the animals. Cu in water was 0.15 ab , 0.12 b , 0.16 ab and 0.19 a mg/L -1 in the center, east, west and south part of the State respectively. Cu concentration in water for animal consumption was low. In conclusion, Cu de ciency was diagnosed in grazing sheep that could be associated with the low Cu content in the drinking water.

CONTRIBUTION TO THE KNOWLEDGE OF THE ARACHNIDS IN THE YUCATAN PENINSULA, MEXICO (EXCLUDING ARANAE AND ACARI)

<p>The Chelicerata are the second group of arthropods with the highest diversity after insects and they can inhabit almost all types of environments. The most current classification recognizes 11 orders and estimates in the number of species vary from 52,000 to 100,000. We have made an extensive literature review on the diversity of arachnids in the Yucatan Peninsula (YP) (excluding spiders and ticks). In Mexico there are 834 known species which represent 6% of the worldwide diversity. In the YP 63 records were found (58 species and 5 genera) of arachnids, which represent 6.8% of the Mexican species. According to our research, 28 of the 58 species (48%) in the YP were also record in other parts of Mexico, the continent and the world. Undoubtedly, the state of Yucatan is the best represented of the YP. In order to have a better understanding of the diversity of arachnid species is important to promote biological compendiums and sampling programs, which will improve the representation of this group and probably increasing the number of local species.</p>

Potential effects of the Mexican energy reform on life cycle impacts of electricity generation in Mexico and the Yucatan region

A national energy strategy in Mexico to 2028, derived from the recent energy reform, projects a considerable shift in the national power generation mix leading to changes on its environmental profile. Therefore, this paper aims to compare the potential environmental impacts of the electricity generation under previous, current and projected energy mixes in Mexico at a national and regional scale considering the Yucatan state as the regional case study. These were estimated with a cradle-to-grave Life Cycle Assessment (LCA) following the CML–IA 2000 V2.05 methodology and including the baseline environmental impact categories. Results indicate that the environmental impacts per generated kWh of electricity have decreased in Mexico from 2007 to 2013 and would keep decreasing at a faster rate until 2028 according to current projections. In Yucatan, the environmental impacts increased from 2007 to 2013 due to an increased diesel consumption, but would decrease by 2028 reaching lower levels than in 2007. From 2007 to 2013 almost all the environmental impacts in Yucatan were lower than the country average due to a higher contribution of natural gas in the power generation mix, while in 2028 they would be similar. Overall, there is a significant difference between the national and regional estimations of the potential environmental impacts due to differences in their power generation mix. Furthermore, the potential introduction of shifts derived from the energy reform in Mexico will have a strong positive influence on the environmental impacts from the electricity generation.