Acta Universitaria

3-9

Authors: René Dionisio Cupull-Santana, Remigio Cortés-Rodríguez, Ervelio Eliseo Olazábal-Manso, Carlos Alberto Hernández Medina

The present research was carried out with the objective of evaluating the physicochemical characteristics and the antifungal activity in propolis from Apis mellifera, coming from the Villa Clara, Cienfuegos and Sancti Spíritus counties in Cuba. Scraping harvesting methods were used to establish wax, ash, insoluble material and resin contents in raw propolis. In addition, in vitro antifungal activity of ethanolic extract of propolis was evaluated for fungi Aspergillus sp., Penicillium sp., Fusarium sp., Trichoderma sp., Colletotrichum sp., and Monilia sp.: the extracts presented high antifungal activity in a wide range of concentrations; also, the physicochemical parameters presented similar values and inside the established ones for international regulations. This study provides information to select propolis according to the wanted applications

26-33

Authors: Estefanía Solari

In this paper, we analyze the job insecurity of youth employed in the province of Buenos Aires, Argentina, according to the dimensions of temporality, insufficient pay and lack of employment protection. First, indicators are generated to evaluate the above dimensions, then it was determined how individual factors affect them thanks to logistic regression models. From the analysis it could be highlighted that the higher the age, having completed secondary education, being head of the household and being in a relationship, the odds of having pension contributions, and earning the minimum wage, increase; the opposite happens in case of being a woman. The same happens in the case of workers who have completed high school education and are in a relationship. Conversely, in the case of women the probability decreases. Finally, the findings emphasize the great importance of high school completion in youth and the importance of establishing public policies to mitigate the problem.

43-50

Authors: Lucía Elena Acosta Ugalde

The Spanish word Exvoto (votive offering) comes from the latin: ex, of and votus, promise. It is a symbol of gratitude on the part of an individual or group of individuals for favors received. Without a doubt, these are materials that represent a way of believing and living the Catholic religion and whose disappearance or devaluation would certainly be regrettable. The purpose of this article is to recover the value of exvotos as a cultural practice; observe their formal structure; and, from this, think about their prospects of continuity or disappearance. The triad of Peirce is used to conceptualize the exvoto as sign, as well as opacity as an element of the discourse and the proposal of a model that seeks to bring us closer to intertextuality in this specific type of cultural product.

3-9

Authors: Carlos Alberto Rangel Rodriguez, Laura Alejandra de la Rosa Carrillo

Nuts possess beneficial properties for health, and are already part of the human diet; however, they are also a health risk to consumers sensitive to protein allergens present in nuts. Therefore, most research on nut proteins has focused on determining nut aller­gens and in generating methods to simplify their identification. This is how proteomic techniques have been recently applied in the area of food research. Proteomics also plays an important role in the study of stored tree nuts, in order to preserve their nutritional properties for the longest period of time possible. Finally, in the evaluation of differences in fruits of the same species, caused by environmental factors allows us to obtain new information regarding proteins present in foods beneficial to health.

20-26

Authors: F. Sandoval-Ibarra, Natanael Melchor Hernández, Susana Ortega Cisneros

In order to understand the causes of 1/f noise in MOS transistors physical theories descri­bing its physical origin, such as the McWhorter theory and the Hooge theory, are reviewed in this paper. Analytical 1/f noise models correlating experimental results based on a long-canal approach have been reviewed as well. Spice simulation models are also described, concluding that these models are also based on the long-canal devices theory. Therefore, it the length of the transistor as to be increased to reduce 1/f noise, it is significant to find out what other parameters are under the control of the designer, and which technique can contribute to reducing the level of spectral power of the noise. Simulation results showing the noise performance when the canal length is changed, L, and the frequency power is changed, β.

37-42

Authors: Maricarmen Luján Hernández, Angélica Vásquez Nogueda, Judith Herrera Fotti

Today, corruption is a relevant topic because, according to citizens’ perception, this pro­blem reflects the situation of a country and vice versa. The way in which people perceive the degree of corruption in their community may vary by gender, age, education, so­cioeconomic status, cultural traits, and other characteristics. The objective of the following research is to determine the relation between the level of corruption, gender and field of undergraduate study. To achieve this, a sample of 362 students enrolled in the semester of January-May of 2013 at ITESM, campus Monterrey were surveyed. Through the use of statistical techniquesvarious relationships were established while measuring the level of corruption by gender and field of undergraduate study. It was concluded that gender does have an influence on levels of cooperation and corruption.

3-8

Authors: Judith García-Rodríguez, Francisca Isela Molina-Astudillo, Víctor Manuel Estrada-Salgado, Migdalia Díaz-Vargas, Martha Beatriz Soriano-Salazar

“Trophic state” refers to the amount of organic and inorganic material having a body of water. The aim of this study was to determine the trophic status of the dam El Abrevadero which were recorded for the physicochemical and biological parameters: water tempera­ture, dissolved oxygen, transparency or Secchi disk visibility, chlorophyll “a” and phos­phorus total monthly. We employed Trophic State Index of Carlson (TSI) of calculating the TSI of transparency (TSISD), chlorophyll “a” (TSICA) and total phosphorus (TSIPT). The physi­cochemical parameters showed a pattern of variation associated with the rainy season and dry, with respect to TSI of Carlson dam El Abrevadero is classified as hypereutrophic.

17-29

Authors: Christopher Lionel Heard, Sazcha Marcelo Olivera Villarroel

The article discusses the effect of the practice of thermal isolation in social housing in Mexico, which involve investment in infrastructure and energy savings for residents and economic, to represent lower costs in the use of electricity for ventilation systems and air conditioning. The problem treated is of vital importance to the cities in the dry and wet region of the country in which human settlements are rising. The study shows the versatil­ity of the Cost/Benefit methodology in evaluating investment options to different climatic and environmental conditions.

37-46

Authors: Luceli Patiño de Peña, Angélica María Cardona Pérez

A study was developed from the research paper Study of academic mortality, pedagogical strategies, and dropout on dropout levels in Colombia and Latin America in order to identify factors that in some way affect increased dropout, such as admissions exams, vocational guidance, economics, and personal difficulties. We also identified the elements of greatest convergence: causes of dropping out, economic difficulties, students’ personal and family histories, secondary education, and, to a lesser degree, suggested strategies that can be used by universities. Therefore, we can conclude that despite the great diversity of studies, the shortcoming lies in the lack of effective policies curtailing university dropout and lack of support for regional education policies to integrate university, society and State.

3-13

Authors: Américo J. Hossne García, Omar Guerra

It is common to obtain agricultural soil samples using the Uhland sampler. The critical index of soil compaction is obtained with the Proctor test. The objective of this work was to perform a physical comparison between the Uhland sampler, with free and forced fall of the hammer, and the Proctor apparatus to assess mechanical alterations of the sample. Standard and modified Proctor instruments were used, as well as the Uhland with free and forced hammer fall. A completely randomized statistical design with ten replicates and four treatments was performed along with the analysis of variance, Minimum Significant Differ­ence and polynomial regression. It was concluded that Uhland and Proctor instruments pro­duced similar results. The penetrating energy of the Uhland was higher than the compacting energy of the Proctor. Humidity in the soil had an influence of the apparent dry density. The solidity ratio of the soil and the air porosity were the parameters that best identified the compaction process for the Proctor and Uhland instruments.

20-27

Authors: Maricruz Romero Ugalde

The "Great Chichimeca" is considered as a region of constant cultural exchanges between sedentary and nomadic groups. It is located in San Juan del Río, México, southwest of the United States. In this research the relationship between the meals that were used in com­memorative rituals and traditional festivities associated with life cycles in populations in the area comprised between Querétaro and Zacatecas are shown. The objective is to demonstrate the possibility of accounting for certain cultural exchanges in the region based on food and specific forms of preparation, identifying transformations and continuities that promote iden­tity regarding ritual commensality. Some of the questions guiding this research are: Is it pos­sible to identify certain constants in the use of corn and chili? How did culinary changes occur from the introduction of turkey to the introduction of pork? Why are there certain dishes with names that have a direct reference to indigenous cultures? In which way is commensality related to international policies such as the right to food or the recognition of certain cuisines as part of cultural heritage of humanity?

3-7

Authors: Matthew Olaniyi Adewumi, Ayodele Jimoh, Olubunmi Abayomi Omotesho

Many observers believe that the on-going liberalization of the world will have dramatic negative effects on small farmers in both developed and developing countries. This study aims to capture the effects of the presence of foreign migrant farmers on small scale farm­ing systems, which are prevalent in Nigeria. The Agricultural Development Project Zone D in which the white farmers settled in the state of Kwara, was used as a case study. Primary data were collected from white farmers as well as from local farmers regarding their situ­ation before and after the arrival of white farmers. Descriptive statistics and analysis of the farm budget were used in evaluating the data. The majority of local farmers (98.63%) transitioned towards sole cropping since the arrival of white farmers in the area. There were significant increases in seed rate, fertilizer and other chemicals, as well as labor inputs per farmer in the area when compared to the situation that was prevalent before the white farmers settled there. Their average farm size, distances between their houses and farms and tractor use reduced significantly, while output per farm size increased considerably since the arrival of white farmers in the area. In order to provide sustainability of the posi­tive development, there is the need to seek a policy option that will calm local farmers who once in a while exhibit signs of dissatisfaction for the way in which white farmers came to settle on their land. These could be achieved through the use of the participatory approach to agricultural development in the area. This approach could also be relevant in other re­gions of the world with similar situations.

19-26

Authors: Juan Manuel Belman Flores, V. Pérez-García

In recent years, and due to problems resulting from global warming, interest has grown in the fields of refrigeration and air conditioning, specifically regarding the use of natural refrigerants and hydrocarbons with low potential for global warming. Such is the case of the use of CO2 as a cold fluid, which has been considered in the scientific community as an adequate alternative to common refrigerants. Nowadays, the use of CO2 in the areas of refrigeration and air conditioning has been recognized at international levels. Therefore, this work aims to show its potential as a natural refrigerant, the causes why this fluid was temporarily replaced by chlorofluorocarbon refrigerants, and its reappearance in the XXI century. It also proposes the use of CO2 in air conditioning in our country by using vapor compression technology, based on the transcritical cycle.

32-35

Authors: Alfredo Campos Mejía, Alexander Pisarchik

Intermittent switches between chaotic and steady-state regimes are observed in experiments with two mutually-coupled diode lasers subject to common white gaussian noise. Both time series and power spectrum analyses yield typical scaling laws for on-off intermittency.

38-44

Authors: Gerardo Ribeiro

Article 5th of the Federal Tax Code of the United States of Mexico establishes that “Tax provisions which institute obligations or tax exceptions to individuals (tax payers) as well as those which establish penalties and sanctions are to be strictly applied.” The purpose of this article is to discuss the concept of “strict application” of tax provisions showing that such concept cannot be sustained based on linguistics nor reason. Therefore a new con­cept is proposed to the tax argument called “making sense” or “constructing sense”.