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This paper argues the origins of research in chemical sciences at the University of Orient, and the first chemical degree course in Cuba. The peculiar origin of the career, as a consequence of the orientation to research towards basic science, promoted by Dr. H. Harry Szmant from whiting the career of Industrial Chemical Engineering, is demonstrated. The creation, purposes and evolution of the Chemical Research Center at the Universidad de Oriente are analized. It is argued that the early decision to organize the Chemistry Conference in 1964, the first on the country, arose from identifying the need to divulgate the results and promote exchange among scientists, It is shown that this event served as platform for the creation of the Cuban Society of Chemistry and the Cuban Journal of Chemistry. [ABSTRACT FROM AUTHOR]

This paper deals with some general ideas about the formation of sciences teachers in the Latin-American context and the necessity of changes in these processes, in order to improve the teacher's preparation to assume the challenges of social development, taking into account the particular context, in order to achieve a quality scientific education for all. It also emphasizes the particularities of the Cuban case, in which the system of teachers' formation considers the initial and continued formation, the research work and scholar practice as indispensable elements. Some experiences and examples in the sciences areas are also presented in the paper. [ABSTRACT FROM AUTHOR]

Tourism is a key industry in Cuba, representing this country an important role in the international market. Thus, there is a need to analyze the tourism research developed by authors and institutions of this country. This paper analyzes the contribution in tourism academic journals (national and international) of those researchers of Cuban institutions. Considering the dynamic evolution in the period 2006-2011 and due the wide extension of the analysis, the paper will be published in two parts. This paper is the second part and shows a ranking of authors, but also the geographic application of the studies, number of co-authors, and the citations of their papers. Finally, the paper highlights some conclusions and recommendations about the current situation of tourism research in Cuba. [ABSTRACT FROM AUTHOR]

Tourism is a key industry in Cuba, representing this country an important role in the international market. Thus, there is a need to analyze the tourism research developed by authors and institutions of this country. This paper analyzes the contribution in tourism academic journals (national and international) of those researchers of Cuban institutions. Considering the dynamic evolution in the period 2006-2011 and due the wide extension of the analysis, the paper will be published in two parts. This paper allows for identifying the evolution of Tourism Research in Cuba and those institutions that has shown a higher performance in researching and publishing their studies in tourism. The second part of the article shows a ranking of authors, but also the geographic application of the studies, number of co-authors, and the citations of their papers. Finally, the paper highlights some conclusions and recommendations about the current situation of tourism research in Cuba. [ABSTRACT FROM AUTHOR]

Introduction: Research is usually considered a reliable indicator of the degree of development. Research in a problematic area such as food and nutrition for a given region, should have an impact on scientific production in agreement with the importance of the problem, the research capacity and the available resources for generating such a research. Objective: To identify some indicators of Iberoamerican research in nutrition and food. Method: Retrospective study of Iberoamerican scientific production in nutrition and food in the last 25 years. The data were obtained from the bibliographic database Science Citation Index Expanded, Journal Citation Reports Science Edition Database 2011, both included in the Web of Knowledge (Thomson Reuters), and the database of the World Bank. Results: 49,808 papers were registered, the 3.20 % of the Health Sciences collection in SCI. The evolution was fitted to an exponential model, N&D (R² 0.962) and FS&T (R² 0.995). The average production in N&D per average population was higher in Spain with 0.659 papers/million. The highest rates of productivity and profitability were found in Guatemala with 12.963 papers/1000 researchers and 1.486 papers/million $ respectively. The average production in FS&T of the different countries per average population was higher in Cuba with 21.624 papers/million. The productivity index was higher in Uruguay with 25.999 papers/thousand researchers. The profitability index was higher in Guatemala with 0.271 papers/million $. Conclusion: There is exponential growth in the two categories studied N&D and FS&T. Productivity and profitability was higher in countries with low R&D (Research & Development) budget. [ABSTRACT FROM AUTHOR]

Copyright of Latin-American Journal of Physics Education is the property of Latin-American Physics Education Network and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de Ciencias Médicas de Pinar del Río is the property of Editorial Ciencias Medicas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper aims to analyze the effect of the vibration mode and forward speed in the reduction of the draft force in the vibrating scarifiers. To complete this objective the experimental research was develop in the areas of production of Agroindustrial Complex Sugar "Boris Luis Santa Coloma", belonging to the town of Madruga, Mayabeque province, where they analyzed the effects of self and forced vibrations (factor A) in the tensile strength of a prototype vibrating scarifiers. (Bayamo 81M). Also analyzed the effects of the forward speed (Factor B) in the draft force demand. The results showed that of these factors, the type of vibration exerted a significant influence on the variability of draft force, the forward speed effects was not found significant, as well as the interaction between both factors. Although was not significant the effects of speed, when exhibit values of 4,5 km/h the effects on the variability of draft force were higher than for the speed range of 1,044 to 3,96 km/h. Similarly it was found that the use of forced vibrations in scarification depth allows a reduction in draft force by nine percent, compared with the use of self vibrations. [ABSTRACT FROM AUTHOR]

In Cuba the biogas installations are an important alternative for the processing of organic wastes in agricultural farms, and so reducing the contaminants and improving its quality as fertilizer, obtaining a renewable energy, the biogas. This combustible gas can be used for food cooking, water heating, the generation of electricity and domestic lighting. In the implementation of the strategy for facing climatic change drew up by the Ministry of Agriculture of Cuba it is considered a measure for the reduction of carbon emission consisting in "Reduce the consumption of combustibles of fossil origin using renewable sources of energy". The paper shows a methodology for make easy the analysis and calculation of the parameters for the construction of ixed dome biodigesters. [ABSTRACT FROM AUTHOR]

This paper shows the development of software for the intelligent control of a six degree of freedom robot manipulator, with artificial vision techniques for the intelligent identification of objects by means of pattern recognition using an artificial neural network. A method of images segmentation, based on regions growth by pixels grouping, was implemented for the objects detection. a mathematical model, based on an alternative trigonometric method, was developed to solve the inverse kinematic problem of this robot. The system was tested on a satisfactory way; identifying different kinds of objects with a high percent of certainty and determining their location in the workspace of robot. [ABSTRACT FROM AUTHOR]

This paper presents a novel feedback technique for fluxgate magnetometers based on second harmonic detection method. This new technique mainly consists of the injection of a sample output current in the excitation coil, thus the resultant magnetic field will be in opposition to the external magnetic field object of measurement. This kind of compensation has been conceived for its implementation on integrated fluxgate microsensors. They are used for systems of gyroscopes and electronic compasses in the inertial control of autonomous agricultural vehicles in Precision Agriculture. [ABSTRACT FROM AUTHOR]

With a view to evaluating the possibility of non invasive sensing of soil compaction by means of the application of a variable electromagnetic field, a theoretical - experimental study of the interaction < electromagnetic field-soil > is made, by using finite element simulation, as well as experimentation in a soil deposit. In a previous paper the influence on the soil response to the action of a variable electromagnetic field is determined in function of the excitement frequency of a field-generator coil and of the distance between the field-generator coil and a receiver coil, measured through the current induced in the receiver coil. Also, validation criteria of the use of finite element analysis during the study of the interaction electromagnetic field - soil, were obtained. In present work, using this analysis method, the possibilities of sensing of soil compaction by means of the application of an electromagnetic variable field is studied. As a result, a high correlation (R²=0,96) among the soil electric conductivity and the density of the induced in a receiver coil current is obtained. Experimentally, increments of electric conductivity of a compacted red ferralític soil were evidenced with increases of soil moisture and compaction, measured through their apparent density. Soil electric conductivity and therefore induced voltage in the receiver coil, correlated with soil compaction, oscillating R² between 95,9 and 98,4% for different soil moisture levels. [ABSTRACT FROM AUTHOR]

This paper gives a characterization of the transmitter Sprayhead D3000 in evening and daytime schedules placed at 1 and 2 m height on a test bench outdoors. The equation of the transmitter, the medium intensity of application, effective range diameter, the coefficient of uniformity, distribution uniformity and an analysis of the distribution pattern were determined. The results were the equation of transmitter with a correlation coefficient of 0,9964, the medium intensities showed lower values during daytime hours to 2 m height of 3,61 mm / h, while the effective range diameter reached values of 13,4 m at night at a pressure of 280 kPa and the coefficient of uniformity of 89,4% at a pressure of 190 kPa; on the distribution pattern there were not significant differences observed. [ABSTRACT FROM AUTHOR]

The finite elements method has been widely used in the simulation of the soil mechanical response. The constitutive models are the mathematical support core of this method and Duncan and Chan's is one of the most used. Therefore, the aim of this paper is to determine accuracy in the prediction of three Cuban clay soils' relationship strain vs. deformation. The soils mechanical properties are determined and the constitutive equations are made in the software Mathcad 14 to accomplish this goal. The results show the model has a large capacity to predict accurately the relationship strain vs. deformation of these soils when there is a plastic failure. However, the model is not able to predict the tensions changes caused by softening or hardening deformations. [ABSTRACT FROM AUTHOR]

The aim of this paper is to analyze the quality of the mechanical harvest of rice seeds, carried out by the New Holland L521 rice harvester machines, at the Rice Farm "Los Palacios". Their technological parameters were evaluated depending on the quality of the harvested product, taking into account some aspects such as: the entire, peeled and/or broken grain, the impurity content and total losses. This resulted in values of 5,2-6,4% for peeled and/or broken grain in the five agricultural yields. On the other hand, the impurity content was among 8,3-9,6%, so that both parameters exceed the established limits. This is mainly caused by: the bad regulation of thresh, the work speed and the poor training of operators. These results allow decreasing losses. During the harvest losses decreased from 206kg/ha to 85kg/ha which represents an economic effect of $ 316 202.04 pesos. This also permits to stop investing about 184 793.4 USD on rice for our population feeding. [ABSTRACT FROM AUTHOR]

This paper presents the partial results of an investigation carried out at the School of Architecture at CUJAE since 1994. It provides the development and results of the work carried out in part one. A critical analysis of inadequate treatment and losses are shown in this article, emphasizing the reasons not to employ this kind of treatment and what to do instead. The whole study is supported by diagrams, illustrations, pictures, maps and other aids that are going to be used in further studies. [ABSTRACT FROM AUTHOR]

This paper describes the strategy and the challenges to be faced in order to transform CUBACIENCIA, an analytic and bibliographical database that includes Cuban scientific production m an electronic resources portal based on the «Open Access Initiative» principles that can promote free access and wide dissemination of research findings in Cuba. The project is based on the development of a data-provider distribution network (repositories and open access journals) and a harvester for gathering metadata of the contents existing in data providers, which will be available for free consultation through a single interface. [ABSTRACT FROM AUTHOR]

The paper presents the results of a study implemented in Cuba from 2004 to 2006, regarding the attitude towards nuclear applications. This study is a response to the need of the Agency of Nuclear Energy and Advanced Technologies to determine the attitude of the different publics towards nuclear energy for the strategic design of communication. For the research, a methodology was used for evaluating the opinion of final users towards nuclear applications in terms of agreement or disagreement, acceptance or rejection. It was deduced from the inquiry about their knowledge, assessment and behaviour. [ABSTRACT FROM AUTHOR]

This paper presents a review of the research findings documented in literature about factors associated with academic scores in college students and their relationship with the quality of higher education in general, using as a reference studies carried out in Spain, Colombia, Cuba, Mexico, and Costa Rica. These factors are grouped in three categories: personal determinants, social determinants, and institutional determinants that, at the same time, hold their own indicators. Emphasis is given to the fact that the search for educational quality is a desired good for different sectors of society, and for which universities fight from different fields, with major concerns in the public sector due to the investment involved. The search for quality implies ah integral review of the university that includes studies about the academic results of students, because those results are an important input and allow the identification of limiting and enabling elements of academic performance and, consequently, facilitate the control of public resources and the social impact mediation. The analysis of the educational quality must include research results about the academic results of the students since it is of great use in the decision making process aiming for a more fair educational system. [ABSTRACT FROM AUTHOR]

The present paper ia a study of the scientific production of Cuban researchers from 1988 to 2004. A search in the data base of Web of Sciences in the field of the author's address with the word "Cuba" was carried out. A total of 7329 articles from all the country were recovered. Among them 838 belonged to CNIC. The field of the author's address was standardized. The articles more quoted were briefly analyzed as well as the institutions most represented. A study of the impact factor related to the most productive institutions was conducted as well as the average quations per articles of the most prolific authors. The most productive institutions and authors are shown. the University of Havanna, the National Center for Scientif Research, the Center for Genetic Engineering and Biotechnology and the Institute of Animal Science are the institutions with the most scientific productivity shown in the Web of Science during the evaluated period. [ABSTRACT FROM AUTHOR]

The objective of this paper is to determine the value of the pH on the condensed vegetable obtained from the juice concentrators, its variance depending on the kind of citrus fruits and its maturity as well as to determine the amount of sodium hydroxide needed for its treatment, to be used to feed the boilers. For this study many samples of pH were taken during the campaign 2008-2009, in a 7 month period. The values of pH were compared to the fruit ratio obtaining a correlation of 0,00149, and by statistics methods it is found that the condensed vegetable pH is constant during the hole campaign and that it is possible to use it to feed the boilers adding to every cubic meter 10,17 g of sodium hydroxide to increase values of pH, from 4 to 8. [ABSTRACT FROM AUTHOR]