• His paper deals with details about how a person's exposure to carbon dioxide affects cerebral blood flow. The information was provided by experimental British patients, as part of a collaborative work with the University of Leicester.

Dr. Max Chacón, professor at the Department of Informatics Engineering, Faculty of Engineering, was awarded the 2011 Jack Perkins Prize by the Institute of Physics and Engineering in Medicine (IPEM) of England, for his publication "Non-linear multivariate modelling Hemodynamics of cerebral hemodynamics with Autoregressive Support Vector Machines.”

 The award, which consists of  £ 250, is given annually to the best paper published during the year in the Medical Engineering & Physics journal, after a review carried out by a specialized committee that evaluates aspects such as the novelty and impact of the research.

 Dr. Chacon thanked the award and noted that this type of survey research confirms the good work being done in this University. "This is an important recognition for us, especially because our paper in the area of cerebral self regulation did not belong to the field of biomechanics, the journal’s strongest line of research, which could have been  the most possible winner”, he said.

The winner added that "all the profits for this recognition are indirect: for example, increasing the bonds of cooperation not only with the university we work with (Leicester), but also with other foreign institutions".

Significant contribution to medicine

The awarded paper is part of a specific area called cerebral hemodynamics. Professor Chacón  is working with two other researchers: Claudio Araya, former student of Master’s degree at the U. of Santiago, and Ronney Panerai from the University of Leicester (England).

 The cerebral hemodynamics acquires vital importance, because the estimates of international organizations involved in the field of health in Chile indicate that by 2025 more people will die from brain strokes than heart attacks. It is believed that the blood flow would be strongly linked to vascular accidents and also with a number of diseases, such as Alzheimer's, arteriosclerosis (carotid artery, mainly), head trauma, vascular dementia and diabetes, among others.

"Cerebral strokes are rising very strongly in the country and the causes are unknown. One thing that causes brain damage is the stronger flow in the arteries. It is known that the brain has a flow control system, and this means that, although the pressure varies in the body, the flow is almost constant in the brain. If there is little flow, one loses consciousness and, conversely, if there is a lot of flow an artery breakdown happens, “Chacón explained.

This mechanism, which constantly generates blood flow into the brain, is what researchers try to model through a data–based nonlinear system. This publication addresses one of the topics related to cerebral hemodynamics, because of the data given by the English researcher who provided the information based on 16 healthy patients who breathe in air with a small fraction (5%) of carbon dioxide (CO2) through a mask. The aim was to know how breathing in this gas affects the regulation of the blood flow in the brain.

"We proved that it is possible to represent changes in the inhalation of CO2 in a person by using this nonlinear model and this has metabolic implications, for instance. We know that breathing in a fraction of CO2 produces changes, which are equivalent to those experienced by people with diabetes, i.e. a metabolic problem, and these problems affect the blood flow in the same way as CO2 does it, “the researcher said.

Prize

The IPEM is an institution dedicated to joining professionals from the physical sciences, clinical engineering, the academic world, the health services and the industry, in order to share knowledge and advances in science and technology. Since 2000, it gives the Jack Perkins Prize in honor of his first journal’s editor, who died in 2000.

• The renowned Journal of Coordination Chemistry dedicated its issue 67 to Dr. Juan Costamagna, academic at the Faculty of Chemistry and Biology of Universidad de Santiago, for his contribution to the development of this journal since 2000, when he was invited to be part of the Editorial Board. The journal aims at disseminating the investigations of renowned researchers in the field of Chemistry of Coordination Compounds in countries like the United States, France, Argentina, South Africa, and Chile, among others. 

In recognition of his significant contributions to the development of the Journal of Coordination Chemistry and in the context of his retirement from the Editorial Board, the journal dedicated a special issue to Dr. Juan Costamagna, researcher at the Faculty of Chemistry and Biology of Universidad de Santiago.

The journal aims at disseminating the investigations of renowned researchers in the field of Chemistry of Coordination Compounds in countries like the United States, France, Argentina, Uruguay, South Africa, Spain, Italy, Mexico, and Chile.

Jim Atwood, who was in charge of issue 67 called “Special Issue: To honor Professor Juan Costamagna on the occasion of his retirement", highlighted in the opening pages professor Costamagna’s “valuable opinion” and his contribution over the years “with his expertise” to the development of this publication.

Atwood pointed out that Dr. Costamagna “has been a consummate collaborator and has brought his talent to the Editorial Board of this Journal; he has published over 100 papers in the field of Coordination Chemistry and has served 14 times as the Chilean delegate to the International Advisory Committee of the International Conference on Coordination Chemistry between 1974 and 2006. He was also an Advisor to the Nobel Prize of Chemistry from 1996 to 2000”. This is the background for this special issue available since December on http://www.tandfonline.com/toc/gcoo20/67/23-24.
 

Contribution to Science

The participation of Dr. Costamagna in the journal dates back to 2000, when he was appointed to the Editorial Board by the journal’s general editor.

Since then, Dr. Costamagna has contributed with countless academic evaluations and several plenary “Online Annual Meetings” of the Editorial Board. The journal has positioned itself as a model in the field of Chemistry of Coordination Compounds. “I think I have modestly contributed to this growth and development,” Dr. Costamagna said.

Regarding his plans in the editorial work, Dr. Costamagna said that he will continue working as emeritus editor for “Communications in Inorganic Synthesis”, an online journal sponsored by Universidad de Santiago.


Translated by Marcela Contreras

• Researchers at Universidad de Santiago, in partnership with researchers at the University of California (USA), developed a software program that includes several applications to study reading comprehension in users of digital texts. They will analyze the reading tracks in students and professionals all over the country to understand the cognitive processes developed when approaching a text on screen.

New technologies have also had an impact on people’s reading habits, as a result of the widespread use of digital texts. However, according to different studies, this change has not improved reading comprehension in Chilean people.  Thus, researchers at Universidad de Santiago have developed a software program that includes several applications to study reading comprehension in users of this type of text.

“Reading comprehension is essential to any field of knowledge. If someone does not have a good reading comprehension level, it will be more difficult for him/her to understand science, mathematics and texts related to financial products or a contract, for example. For this reason, we designed computerized environments for users to develop information processing strategies that allow them to process this information in a way that eases their understanding,” Dr Héctor Ponce, professor at the Department of Accounting and Auditing and an expert in information systems, said.

To design these environments, Dr Ponce and other professors at Universidad de Santiago have developed several software applications to improve reading comprehension of digital texts by including information processing strategies, like note-taking, cause-effect diagrams, sequences and comparisons. These strategies were turned into applications that complement each other, proving the effectiveness of this technology.

The results encouraged researchers to conduct further research on how Chilean people read and understand. They are currently working on the Regular Fondecyt Project (1151092) “Facilitation of cognitive processes by means of different computer-aided information processing strategies: An eye movement analysis.”

“Although we process information in different ways, there area some repeated patterns that we are trying to identify through this study. This why we will asses the cognitive strategies that a person uses when reading,” the researcher explained.

“For this purpose, we will use a computer-connected device called ‘eye-tracker’. It detects where on the screen the user is looking at, it follows the eye movement and detects how long someone spends watching objective elements, like words, for example, or the eye movement track when processing a text, among other aspects,” he added.

To inquire into how strategies help in understanding a text, tests will be run with plain texts without strategies, and with other texts that involve individual and multiple strategies.

The research team includes experts in cognitive psychology, like Dr Verónica Figueroa, co-investigator and researcher at Universidad de Santiago, and Dr Richard Mayer, professor at the University of California (Santa Barbara), who is collaborating in the study.

The project implementation started in March this year and it will involve school and university students and professionals. The study is divided in three phases: first, the design of the material to be used; then, testing and data collection through the eye-tracking device; and finally, the analysis of the collected data.

According to Dr Ponce, the results of the study could have two potential impacts. One is the software improvement, as the most effective strategies could be assembled to understand what is being read. And the other, the possibility of improving the content presentation in textbooks and the presentation of specialized information, like the one related to online products sales, health care plans, and contracts, among others.

“In a society, it is very important for people to be able to understand what they read, as one of the natural consequences of a good comprehension is a better decision-making,” Dr Ponce stressed.

Translated by Marcela Contreras

• In large cities like Santiago, the quality of life is strongly related to the quality of the environment of the urban settings we live in. This is the core idea of the study “Socio-ecological quality in urban settings: improvements for a human-scale sustainable environment. Municipality of Quinta Normal,” a Dicyt project developed by Dr Alexandre Carbonnel and Rodrigo Martin, both professors at the School of Architecture of Universidad de Santiago. The study seeks to provide a tool for assessing the quality of urban life, considering environmental conditions (thermal, acoustic, and atmospheric ones) at urban settings.

   

  “Socio-ecological quality in urban settings: improvements for a human-scale sustainable environment. Municipality of Quinta Normal,” is the name of the study conducted by Dr Alexandre Carbonnel and Rodrigo Martin, both professors at the School of Architecture of Universidad de Santiago. The project has been funded by the university’s Scientific and Technological Research Department (Dicyt, in Spanish) and it has the purpose of providing a tool for measuring the quality of urban life, considering environmental conditions (thermal, acoustic, and atmospheric ones) at urban settings.

  The first measurements will be done at the municipality of Quinta Normal, an area of the capital of 12.4 square kilometers wide, with a population of 105 thousand people, according to the national census of 2002.

  This municipality is significant for the study, as it displays several special characteristics: In spite of being close to Santiago Centro, it has several industries; it adjoins Quinta Normal Park, one of the largest green areas of the capital managed by the Municipality of Santiago; and it is traversed by some of the busiest streets of the city, like Matucana, Costanera Norte Highway, Avenida San Pablo, and Central Highway (General Velásquez).

  The first hurdle to be cleared was to define the study areas. For this purpose, the research team developed “a methodology to identify the use of the urban setting as of the use of transportation and schools, what will allow pinpointing the nodes of very intense use and measure their environmental quality,” Carbonnel said.

  In order to relate the urban environmental quality to the use of urban infrastructure and services, variables and indicators related to transportation, health care and education coverage, cultural and commercial spots, green areas, and others, will be analyzed. The researchers will use some software programs (QGis and Grasshopper3d) to cross-check the information and identify the places with higher people density and more use of space.

  Once they know the places with higher density and more use, they will measure the urban environmental quality. This process will be based on thermal, acoustic and atmospheric variables, providing a true and varied environmental record of the places to be studied 

  Study impact

  According to Dr Carbonnel, the study impact is aimed at “providing municipalities, regional governments and the community with an important information tool that includes environmental indicators to orient them at managing and making local public policies and to contribute to a better use of the funds invested in infrastructure.”

  Dr Carbonnel also said that this methodology will open doors to the creation of a new line of products. “These innovations should aim to democratizing environmental information, in agreement with the vision of the Smart City Lab research center of our university.” Both researcher work at this center, together with other professionals of the School of Psychology and the Departments of Industrial Engineering, Geographic Engineering, Electric Engineering and Computer Engineering.

  Translated by Marcela Contreras

• With a space of 2,755 m², the five-floored building will be home to the Center for the Development of Nanoscience and Nanotechnology, the Aquaculture Biotechnology Center and the Soft Matter Center. The cost of the building construction amounted to about CLP 5,000 million.

In a context in which Chile only invests 0.39 of its GDP in research, the President of Universidad de Santiago de Chile, Dr Juan Manuel Zolezzi, highlighted the importance of this new space that will contribute to research and development in the country.

“This is one of the state-of-the arts buildings in Chile with regard to university research and it is an incentive for new researchers to continue innovating in key areas for the development of Chile,” he said. He added that Universidad de Santiago de Chile is a leader in technology transfer.

Senator Guido Girardi, who heads the Challenges for the Future. Science, Technology and Innovation Commission of the Upper House, valued the work done by public universities.

“These universities take charge of basic sciences on their own. Particularly, Universidad de Santiago has had the wisdom to connect basic sciences to the problems of the country and to generate innovation to solve these problems,” he said.

A few months ago, Dr Girardi visited the Center for the Development of Nanoscience and Nanotechnology (Cedenna, in Spanish) where he met with professionals in this significant research field. After the opening ceremony he congratulated the university on the new facilities.

The centers

Representatives of the centers that will occupy the new facilities expressed their satisfaction with the architectural configuration of the building that facilitates research development.

Dr Francisco Melo, Head of the Soft Matter Center that gathers together scientists in the fields of Physics, Chemistry, Biology and Engineering, said that the new space will offer endless opportunities for a better science development and for positioning the university at an international level.

For her part, Dr Dora Altbir, Head of the Cedenna, said that the possibility of bringing together scientists from different fields will allow a more active collaboration than the one that the university has now.

Eugenio Spencer Ossa, Head of the Aquaculture Biotechnology Center (CBA, in Spanish) said that the new building will allow to further scientific research and contribute to improve domestic industrial production, like salmon farming.

Architecture

The Rector Eduardo Morales Santos Research Building, with a total surface of 2,755.15 m², is located in the central campus of the university. Its design is a geometric reinterpretation of the heritage buildings of the institution designed by the architects Héctor Valdés, Fernando Castillo Velasco, Carlos García Huidobro and Carlos Bresciani and built between 1957 and 1967. The building’s name is a tribute to the first democratically-elected university president after the dictatorship.

Translated by Marcela Contreras

• After the success of Nutrisato- an innovative natural fertilizer that increases by 50% the size of fruits, vegetables and plants- in the international market, its creators opened an agricultural additives company.

In his search for environmentally friendly biotechnological solutions, Alejandro Muñoz, biochemist and student at the Biotechnology doctoral program of the Faculty of Chemistry and Biology of Universidad de Santiago, developed an interesting plant biostimulant based on organic molecules which is able to increase fruits, vegetables and flowers twice their size in the same period of time.

Later, Carla Céspedes, an agronomist from Universidad de Chile, and Rodrigo Ferreira, student at the Commercial Engineering program of the Faculty of Administration and Economics of Universidad de Santiago de Chile, joined the project team and took the responsibility of placing the product in the agricultural market.

After the positive outcomes of testing Nutrisato in peppers and tomatoes, the students participated in the Brain Chile program contest and won the first place. They used the funds that they were awarded to continue developing the product to a level that they never expected: today, they have their own company called Ingeniería y Biotecnología Limitada, Atama Biotech Ltda.

Nutrisato in the market

After the Brain Chile Contest, they continued testing Nutrisato. They found that it was harmless to people and the environment and it also “doubled the size of the products, increased the production of fruits by 50% and the production of biomass in vegetables by 30%,” Alejandro Muñoz explained.

Carla Céspedes, who is responsible for the agronomic development of Nutrisato, explained: “The first products in which we tested the biostimulant were harvested in April, but after the contest, they were left abandoned in an area with Andean climate. In that context, we realized that the fertilizer reduced the cold stress in plants and enhanced their hygroscopic properties.”

Supported by recent tests, the researchers confirmed that the fertilizer worked in every product in which they used it, like spinach, celery, parsley, coriander, tomatoes, peppers, onions, cherry tomatoes and ornamental plants like tulips, roses and daisies.

Now they are testing the product in hydroponic lettuces and tomatoes, and in berries and citrus fruits, in Valdivia.

With regard to the marketing of the product, Rodrigo Ferreira, who is in charge of the company’s management and sales, says that they created Nutrisato Hogar, a product which is targeted at people who grow their own vegetables in home gardens. The product will be in the market soon.

The researchers say that they have enjoyed their work with Nustrisato, because they are doing what they like to do. For this reason, they have continued developing innovative products, like Raizato. “Raizato is a super soil enhancer that adds organic matter to the soil and enhances the growth of roots and leaves,” Alejandro Muñoz said.

Translated by Marcela Contreras

• Universidad de Santiago’s Innovo Center was awarded these funds to run the Flexible Allocation Seed Grant Fund for four years in order to accelerate the development of innovative scientific and technological business ventures of international impact.
• “This grant is in recognition for the work done by the Center’s Business Incubator, which has dedicated itself to promote the innovation and entrepreneurship culture and has helped to create new technology-based companies,” Innovo’s Director said.

In order to strengthen scientific and technological business ventures, the Chilean Economic Development Agency (CORFO, in Spanish) awarded Universidad de Santiago’s Innovo Center 2,600 million pesos to run the Flexible Allocation Seed Grant Fund (SSAF, in Spanish) for four years. These funds will be earmarked for supporting innovative, high-impact start-up companies.

“The objective is to accelerate the development of local scientific and technological business ventures at an early commercial stage which are based on technologies in their last mile of development and have a potential international impact. We have 500 million pesos available for the first year and then, 700 million pesos every year,” Luis Lino, Innovo’s Director, explained.

These resources will be given to scientific and technological entrepreneurs through contestable funding. Those who are interested and meet the requirements will have to apply for it. For the business ventures that are granted SSAF funds, Innovo Center considers a first stage of international commercial validation. For this purpose, Innovo has 10 million pesos available, and for the second stage of commercialization support, it has 50 million pesos. Both stages require co-funding, as entrepreneurs will have to provide 25% of the total cost of the project.

“The contestable funding call will include entrepreneurs with technological projects, as well as other Chilean academic or research centers. The first call is scheduled between August and October this year and the projects will be evaluated according to their innovation degree, teamwork, technology development and their impact on the country,” Lino explained.

In Director Lino’s opinion, this grant is in recognition for the work done by the Center’s Business Incubator, which has dedicated itself to promote the innovation and entrepreneurship culture and has helped to create new technology-based companies.

Today, 33 companies are being incubated in fields like engineering, life science, biomedicine, and information technology with impact on industry. Some business ventures that are worth to mention are the development of a tidal power harvesting equipment, a biotechnological treatment for mining industry liquid wastes, the first electric car developed in Chile and a new energy dissipation system for buildings, among others.


Translated by Marcela Contreras

• The project, led by Dr. Ricardo Salazar, professor at the Faculty of Chemistry and Biology of the University, aims at decontaminating the water from dyes waste and additives, by using electricity and solar energy.

The textile industry in Chile was born in the mid-nineteenth century and expanded thanks to the measures of protection of the internal market which were implemented at that time. Another factor was the arrival of Palestinian immigrants that gave prosperity to the development of the industry.

However, as all industrial activity, this industry was also a contaminant, due to the use of water in its tasks.

This situation becomes a serious problem when you consider that our country has  supply and drought problems. In this context, Dr. Ricardo Salazar, an academic at the Faculty of Chemistry and Biology at the U. Santiago, is leading the Fondecyt project: "Degradation of dyes in wastewater from the textile industry by electrochemical oxidation technologies.” With this project, he aims to provide a solution for wastewater reuse in this process.

The study comes from a previous work by this expert that consisted in analyzing water decontamination of pesticides used in the wine industry. "The first two projects involved water treatment in the laboratory and comprised a chemical study. Now, however, I proposed the construction of a pilot plant to treat more wastewater from the textile industry”, Salazar said.

The project aims to be a contribution to environmental conflict resolution. This is the vital motivation for this academic, who seeks to decontaminate waters that contain dyes wastes and additives. To achieve this, he will work with electricity and solar energy and without using chemicals.

In addition, Dr. Salazar adds that "laws are becoming more stringent for industries in terms of technology demand and waste disposal rates. Therefore, the industries will have to be prepared. The idea is to step forward and provide an approach to this conflict and be useful in the future. "

Purification Process

The purification process is performed by the hydroxyl radical, which derives from water oxidation. This element reacts with the organic components present in the water, degrades pollutants and transforms the contaminant organic compounds into carbon dioxide.

Some of the steps included in this four-year project are: to finish the work in the laboratory, which aims to observe what happens in the whole process; identify each of the compounds that are produced and, finally, build a pilot plant. In this last stage, the scholar has the direct support of Dr. Julio Romero, project co-investigator who is also a researcher at the Faculty of Engineering of the University.

For Dr. Salazar, the importance of the research that he develops lies, mainly, on the human capital formation and in the "responsibility of changing the image of research in the country. Our work could contribute to the enterprise, the industry and, obviously, the University, as we could get the latest technological equipment to develop the project and internationalize the name of the institution. "

By Marcela González

• “Broccoli’s myrosinase enzyme production and encapsulation for its use as a food supplement” That is the name of the Fondef project recently awarded to Alejandro Angulo, a graduate of Universidad de Santiago. In the VIU line (Valorización de la Investigación en la Universidad, in Spanish), the funds will allow to develop a capsule to prevent different cancers.

It is well known that eating vegetables provides many health benefits; even more: some of them have disease preventive properties. Like broccoli, for example, that according to different studies, can be a natural anticancer agent.

Based on this idea, Alejandro Angulo, Biotechnology Engineer graduated from Universidad de Santiago, submitted the project “Broccoli’s myrosinase enzyme production and encapsulation for its use as a food supplement” to the IV VIU Contest of Fondef (Fund for the Promotion of Scientific and Technological Development) and he was recently awarded the funds. The initiative has the purpose of developing a capsule to enhance the natural ability of the broccoli to prevent different cancers.

Alejandro Angulo, director of the project, explains that this vegetable is able to produce some antioxidant and anticancer compounds called isothiocyanates, like sulforphane, that is highly powerful. The precursor to this compound, the myrosinase enzyme, is found in broccoli. When you chew it, its tissue breaks down, the enzyme and the substrate react and sulforphane is naturally released. “If we have more optimal or high-activity enzymes, we could maximize the content of these anticancer compounds,” the researcher said.

For the above, he proposes to create a capsule containing purified enzyme that, when eaten with broccoli, increases the sulforphane content in the body, and therefore, its anticancer effect. However, the researcher warns that the product “would allow preventing cancer, but it would not be a treatment for cancer.”

The researcher says that the idea of developing this food supplement arose when he was looking for a topic for his dissertation work and contacted Dr. Andrea Mahn. She was working on a Fondecyt project that sought to transform broccoli into a functional food. “I focused on the broccoli enzyme that acts as a catalyst for the chemical reaction that releases the anticancer compound, and aspect that she was not studying. In my dissertation work I was trying to describe this enzyme to then purify it and leave it ready to be used in the product. It was then when we thought of developing a food supplement,” he remembers.

His idea was one of the 12 proposals submitted by Universidad de Santiago that won the last VIU Contest version, a historical record that ranks our University in the first place this year. The study will have the support of the Department of Technology Transfer (DGT, in Spanish) to move forward to the ultimate goal: to develop the product for market.

The project is at its first stage that includes a business plan and a work plan; then it will be evaluated to continue to the second stage: the project implementation. “In the long term, we expect to meet all the project stages and position the product as a recognized brand. The idea is to position the brand and sell our product,” the researcher concluded.

Translated by Marcela Contreras

• A new index is the result of the study conducted by a research team at the Department of Informatics Engineering of Universidad de Santiago, led by Dr Max Chacón. This may be a great contribution to improve early detection and measurement of neurodegenerative diseases, like amyothrophic lateral sclerosis, Alzheimer’s disease, Parkinson’s disease and other alterations in cerebral hemodynamics, including cerebrovascular accidents, and subarachnoid hemorrhages, among others.

Cerebral autoregulation is a mechanism which aims to maintain stable cerebral blood flow, despite of the changes in blood pressure.

In order to measure this mechanism, the Aaslid Tiecks method is widely used, but it is not accurate and sometimes it provides false positives that make difficult to differentiate between healthy and sick subjects.

During the study conducted by academics of our University in partnership with the Department of Cardiovascular Sciences at the University of Leicester (United Kingdom), when the new model was applied to 16 healthy men, promising results were observed. 

This new index uses two parameters that are obtained directly from the response signal of the brain to a decrease in arterial blood pressure caused by the sudden release of bilateral thigh cuffs, and a third parameter that measures the difference between the gradient of this response and the change in arterial blood pressure.

“This new index means an improvement in the whole system. The former index did not allow differentiating between healthy and sick individuals in a correct way. When you see the results of the tests, there is an improvement in the evaluation of healthy subjects. The next challenge is to test the index in pathological cases, to confirm the results already obtained,” Dr Chacón said.

University support

Professor Chacón stressed that the study was “completely conducted at the university.” He also highlighted the support that they received from Universidad de Santiago, as the study was brought forth thanks to the contribution of the Department of Scientific and Technological Research and the Department of Informatics Engineering.

Besides, professor Chacón expressed his gratitude to his work team, made up of Dr José Luis Lara, co-author of the study and professor at the Department of Informatics Engineering, and Dr Ronney Panerai, also co-author of this work and professor at the University of Leicester. The researcher also thanked Dr Gonzalo Acuña and Dr Millaray Curilem, both professors at Universidad de la Frontera, who did not formally take part in the study, but contributed to make this research a reality.

Publication of paper

The study results were published in the paper ‘A new model-free index on dynamic cerebral blood flow autoregulation’, where the new index is proposed. It represents a breakthrough in medicine.

The paper was also published by Plos one, one of the most important scientific journals around the world. According to Dr Chacón, this journal is one of the fastest means to publish, so it provides a way to disseminate the results of his work.

He explained that his work “should have a big impact because it is a useful tool at the service of medicine. As it is useful and shows concrete results, the paper might be cited in several occasions.”

Translated by Marcela Contreras