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Marine Natural Products (MNPs) isolated from samples collected in Colombia have been an object of study since the early 1980's; however, this information is neither integrated nor compiled. This systematic review describes the articles published in scientific journals up to December 2019. 173 papers met the inclusion criteria of focusing on MNPs obtained from specimens collected from Colombian seas; all original papers written in English, Portuguese or Spanish. The selected papers were mostly authored by researchers from Colombian groups, with low interaction amongst themselves. 99.4% of the papers studied samples collected from the Caribbean Sea; 183 species were studied, mainly sponges and octocorals. In this study, 1,690 compounds (238 new ones) were reviewed, mainly diterpenes and sterol derivatives. Of the selected papers, 76.8% measured various biological activities, including antibiotic (34%) and anticancer (30%). These papers were published in 51 journals (74.6% were international). In conclusion, scientific work on natural marine products of Colombian origin has incremented over time. The most relevant opportunities to address and fill existing gaps comprise: exploring Pacific Ocean organisms and several of the misrepresented taxa; promoting strong interactions amongst the MNPs research groups, and accordingly with other areas of knowledge; and having the productive sector participate in MNPs research. [ABSTRACT FROM AUTHOR]

Colombia is one of the most inequal countries in Latin America, which at the same time, is the most inequal region of the world. Even though this situation is discouraging it is not new, the difference lays on the importance that this situation has been taken in the political agenda in the nation, awakening multiple expectative between the citizens who has been the eternal losers: the poor. This paper focuses on the challenges that the new government of Gustavo Petro faces in matter of the inequality and poverty that affects over the half of the population in Colombia, at the same time provides a context of the Colombian case in the conjuncture of global and regional socioeconomic changes that incident on the chances of fulfill structural transformations at the social policy. Although this research acknowledges a large spectrum of inequalities existing in the territory (gender, generational, ethnic, racial) it focusses on the income inequality. This analysis takes place based on the data of specialized sources on the subject and the monitoring fluctuations of inequality in Colombia in the last decade. [ABSTRACT FROM AUTHOR]

The aim of this article was to review the relationship between narrative and information inside the Commission for the Clarification of Truth, Coexistence and Non-Repetition (CEV, from its Spanish acronym). In addition, this article examines the implications of the use of narrative to build truth, specifically the truth that the CEV is seeking, and elucidate the approach of truth in which it is situated. For these purposes, we analyze the method used by the CEV to collect testimonies and upload those to the Mission Information System (SIM, from its Spanish acronym). In this paper, we identify the SIM's scope and limits, and discuss the Commission's statements about the characteristics of its final report in light of the use of information and the narrative strategy to build truth. We concluded that the relationship between the categories of narrative and information reflects the epistemological problems inherent to the social sciences regarding the tension between objectivity and subjectivity. Furthermore, the validity of the CEV's elaborations will depend on the rigor of contrasting different versions and sources, rather than the amount of information it collects. Likewise, we highlight the relevance of the role that SIM played in opening up to new technical and methodological tools for uncovering the truth and monitoring human rights in Colombia, and the rest of the world. Nonetheless, there needs to be consideration for the complexities and dilemmas that information sciences deal with when analyzing social reality. [ABSTRACT FROM AUTHOR]

The problem of water availability and its important role in the agricultural sector, specifically in the cultivation of coffee, which has historical, cultural, and economic importance for Colombia, requires a study of the water footprint in this country. This paper presents the results of a study of the water footprint of coffee production (cultivation and wet processing) in Colombia by the traditional and ecological wet-processing methods. To this purpose, the Water Footprint Network methodology was followed according to the Water Footprint Assessment Manual (2011). The green water footprint of coffee production in Colombia was 8,746 m³ t-1 and does not have a blue water footprint as it does not require irrigation, while the gray water footprint was 7,000 m³ t-1. When the traditional wet-processing method is used, the blue water footprint is 4 m³ t-1 and the gray water footprint is 3,200 m³ t-1, while if the ecological Becolsub® technology is used, the blue water footprint is 0.60 m³ t-1 and the gray water footprint is 1,739 m³ t-1. For the Ecomill® technology, the blue one is 0.55 m³ t-1 and had no gray water footprint because it does not generate any water discharge and the little leachate that it produces is reincorporated into the process. This implies that the Becolsub® ecological processing method reduces the water footprint by 45.7% and 99.9% with the ecological Ecomill® process (no wastewater discharge) compared to traditional wet processing technology. Compared to other countries, Vietnam has the lowest green footprint in coffee cultivation, followed by Colombia, Ethiopia, Brazil, Peru, and Indonesia. The water footprint of coffee depends on the climate and yields, consequently, the water footprint of the coffee crop varies significantly between locations and the evaluation period. [ABSTRACT FROM AUTHOR]

The objective of this paper is to show experiences of political socialization between parents and children in Colombia. It is based on a two-way vision of parenting and political socialization. The political is understood as a dimension of the social that has a double character: conflicting and deliberative. In that sense, political socialization can lead to both perpetuating or transforming conditions and political orientations received. The research is qualitative, with data coming from semi-structured interviews conducted with the mothers and fathers of three families. The results show different experiences through which the families encourage critical thinking and construct political notions related to peace, otherness, participation and social inequality. [ABSTRACT FROM AUTHOR]

This paper presents the analysis of a regional groundwater model via Feflow in tropical regions using two techniques: pilot points (PP) and constant zones (CZ). These methodologies allow the proper identification of biased parameters and heterogeneities of hydraulic properties. For this purpose, we developed a numerical density-variable model that is limited to reinterpreted data from real measurements. For the CZ, the initial parameters are considered constant; in contrast, in the PP technique, the initial parameters are assigned according to interpolations using in-situ point measurements. The developed model was applied in an area under the influence of the Inter-tropical Convergence Zone, located in the middle valley of Magdalena (MMV). This area is important in the development of Colombia due to its contribution to Gross Domestic Product, and it has been subject to significant changes in land use, as a result of intense economic activities. The established model shows a link between the observed state variable (hydraulic head) and hydraulic conductivity (K) proving the importance of spatial heterogeneity in K. The model is calibrated in order to establish K, the porosity and the specific storage capacity, reducing the mean square error of the state variable dependable on the observation points. The results show that the PP system approach provides a better heterogeneity representation and shows that each parameter is sensitive, and does not depend on other parameters. This research compiles the first breakthrough toward a methodology to assertively restrict a highly parameterized inverse regional model in a tropical basin. [ABSTRACT FROM AUTHOR]

This paper is focused on working under the line of sustainability in small-scale informal gold mining projects, specifically in Colombia. It is interesting to study Artisanal and Small-Scale Mining (ASM) in Colombia from a business perspective as an activity that generates economic and sustainable development. ASM has great challenges to overcome in order to achieve sustainability in the industry, among them is to overcome informality in the sector, and thus be able to promote the development of a legally constituted economic activity. To achieve this objective, the National Government of Colombia has implemented a National Mining Formalization Policy, encouraging formality through mining formalization and regularization projects. In this work a review is carried out on the aspects that revolve around a Sustainable Business Model; use is made of the business modeling tool Canvas, whose input is secondary information sources. to present a Sustainable Business Model around small informal gold mining with a view to contributing to the purpose of achieving mining formality in operations in the territory. [ABSTRACT FROM AUTHOR]

This article describes and analyses the contents published in digital media during the 2014 presidential election in Colombia in order to identify the informative impartiality and factuality of the digital press. The paper is based on the Interpretive-Hermeneutic methodology and provides a case study and a content analysis of the web articles published between May 25 and June 15 of 2014 by El Tiempo and El Espectador newspapers. The findings show the use of one informative source alone and the limitation of testimonies to personal opinions of politicians, prioritization of content about politicians and campaign events rather than an analysis and a presentation of the government plan, and a strong presence of peacerelated topics and support for the presidential reelection. It is possible to conclude that the discursive resources of both newspapers reduced the written narrative and prioritized the use of images and videos establishing news that, even though broaden the format in terms of information, simplify and modify the informative elements related to the fact-event. [ABSTRACT FROM AUTHOR]

This paper presents the main results of a Master's in Geography thesis written in the University of Chile, titled Residential Segregation and Inequality in the Access to Collective Education, Culture, and Recreation Services in Bogotá-Colombia. It carries out a critical discussion of the factors that influence the socio-spatial segregation of the population and their effects on accessibility to urban services faculties. On the basis of a territorial and statistical analysis, it shows how the characteristics of Bogotá's urban model have led to a strong correlation between spatial patterns of high socioeconomic segregation and low quality of life. This segregation reinforces the low-income population's negative conditions, deriving from unequal access to collective services, mainly education, culture, and recreation, which are spaces theoretically recognized due to the production of social capital and, therefore, of social integration. [ABSTRACT FROM AUTHOR]

The objetive of this paper is to determine the enabling conditions for exercising participatory budgets in Bogotá. An analysis of the citizen participation regulatory framework in Colombia is introduced in order to understand the existent conditions for the execution of democratic budgets. After, a diagnostic of the main national and international citizen participation programs is completed using Arnstein’s “participatory ladder”, highlighting the failures in promoting citizen participation and in the development of participatory budgets. Finally, the last chapter presents a proposal to synthetize conditions that will enable the development of citizen budgets as well as the lessons learnt from international and national cases. [ABSTRACT FROM AUTHOR]

The paper analyzes the impact of the El Niño and La Niña phenomena on both precipitation and agricultural production in the Department of Atlántico. Historically, droughts, anomalous rainy periods, and floods have constantly affected this region. Findings show that under El Niño conditions, rainfall is below average, while La Niña causes above-average rainfall. Sesame and banana yields increase when rainfall is above average (usually under La Niña conditions) during the short dry season and both the first and second rainy seasons. The above-average rainfall in the dry season has a positive impact on cassava yields. Corn yields increase if the recorded rainfall in the short dry season is above average and decrease under above-average precipitation in the second rainy season. Bean yields decrease when rainfall is above average during the first and second rainy seasons and increase when rainfall is above average in the short dry season. Cotton yields decrease in cases of above-average rainfall in the second rainy season, while sorghum does not present noticeable responses to precipitation anomalies. [ABSTRACT FROM AUTHOR]

Fine-grained and mainly reddish color, compact and slightly breccious and vesicular pyrometamorphic rocks (natural clinker) are associated to the spontaneous combustion of coal seams of the Cerrejón Formation exploited by Carbones del Cerrejón Limited in La Guajira Peninsula (Caribbean Region of Colombia). These rocks constitute remaining inorganic materials derived from claystones, mudstones and sandstones originally associated with the coal and are essentially a complex mixture of various amorphous and crystalline inorganic constituents. In this paper, a petrographic characterization of natural clinker, as well as the application of the X-ray diffraction (Rietveld method) by mean of quantitative analysis of its mineral phases were carried out. The RIQAS program was used for the refinement of X ray powder diffraction profiles, analyzing the importance of using the correct isostructural models for each of the existing phases, which were obtained from the Inorganic Crystal Structure Database (ICSD). The results obtained in this investigation show that the Rietveld method can be used as a powerful tool in the quantitative analysis of phases in polycrystalline samples, which has been a traditional problem in geology. [ABSTRACT FROM AUTHOR]

The aim of this paper is to identify digital territorial segregation in the city of Bogotá, Colombia. The primary source of information is the Quality of Life Survey (ECV) made in Bogotá in 2007. Once the elements of the theoretical framework are exposed, the research results are addressed: 1) Internet connection and computer ownership in households in the localities of Bogotá, and 2) relational indicators for assessing territorial segregation in the city. Research demonstrates that digital territorial segregation in Bogotá is a fact that cannot be denied nor hidden. [ABSTRACT FROM AUTHOR]

Metamorphic pressure and temperature trajectories are generally used as tools to interpret the tectonic history of deformed belts of rocks that record past activity along active plate margins. The pre-Devonian metamorphic sequence of the Silgará Formation forms part of the ancient basement of the central Santander Massif, including pelitic schists, siliceous schists and intercalation of amphibolites accompanied by marble. This metasedimentary unit has been affected by Barrovian type metamorphism under middle-pressure/high-temperature conditions. This paper presents on the relationship of tectonic processes to pressure-temperature paths development. Detailed petrologic analysis of pelites and related rocks has been used to constrain the P-T history of this region in the eastern colombian cordillera. Mineral assemblages and Geothermobarometric calculations indicate metamorphic temperatures and pressures of 400-600 °C and 4.0-6.5 kbar, respectively. [ABSTRACT FROM AUTHOR]

Metacarbonate rocks (pure and impure marbles, carbonate-silicate rocks, calc-silicate rocks and carbonate-bearing silicate rocks) form a very complex group within the metamorphic sequence of the Silgará Formation at the central Santander Massif(CSM). These rocks are interpreted as derived from a sedimentary sequence (including limestones and dolostones, carbonate-bearing mudstones, sandstones, tuffaceous and evaporitic sediments and marlstones) overprinted by near-isochemical regional metamorphism. They usually appear as scarce intercalations from millimeter up to meter scale, within the high-grade pelitic rocks, in the lower part of the metamorphic section, although the proportion of metacarbonate rocks can be higher and different marble layers are exploited. We report for the first time the occurrence of a "reaction calcic exoskarn", which corresponds to such metacarbonate rocks, taking into account that a skarn can be developed during regional metamorphism and by different metasomatic processes, adjacent to intrusive bodies, along faults and shear zones, and what defines these rocks as a skarn is its mineralogy, which includes a variety of calc-silicate and associated minerals, usually dominated by garnet and pyroxene. Therefore, this paper focus attention to the occurrence of metacarbonate and related rocks, which occurs as small scale reactions zones that show a gradational contact from garnet-bearing pelitic rocks to marbles or carbonate-silicate rocks, giving particular interest to the calc-silicate rocks, which are characterized by the presence of elongated grains of banded clinopyroxene (diopside) and scapolite and massive or scattered garnet. Several reaction-zones occur in the contact between impure calcite marble and garnet-bearing metapelite and the sequence of mineral assemblages in these reaction zones is: biotite + plagioclase ± K-feldspar ± garnet (Zone I), biotite + plagioclase ± K-feldspar ± garnet ± staurolite ± epidote (Zone II), plagioclase + amphibole ± garnet + epidote (Zone III), amphibole + diopside + garnet + plagioclase (Zone IV), plagioclase + diopside ± scapolite (Zone V). epidote ± calcite (Zone VI), and calcite ± dolomite (Zone VII). [ABSTRACT FROM AUTHOR]

The National Institute of Geology and Mining, INGEOMINAS -- Colombia, and the Federal Institute for Geosciences and Natural Resources, BGR -- Germany, perform since 1997 as a joint venture multi-parameter measurements at the Galeras volcano, in the southwest of Colombia. Since the end of 1998 the Multi-parameter Station at Galeras (Estación Multiparámetro del Galeras -- EMG) includes the continuous monitoring of electromagnetic variations. The electromagnetic (EM) station is located at the north-eastern foot walls of the central cone inside the caldera. During almost six years of electromagnetic monitoring, the data did not show significant variations of the electromagnetic field, which could be related to the volcanic activity. In July 2004 a new active period of Galeras began with two strong ash emissions. During both emissions strong self potential-(SP) signals were recorded lasting for several hours. The present paper will present the data which could give some indications on the movements of liquids during ash emissions. [ABSTRACT FROM AUTHOR]

Automatic classification of seismic signals has been typically carried out on feature-based representations. Recent research works have shown that constructing classifiers on dissimilarity representations is a more practical and, sometimes, a more accurate solution for some pattern recognition problems. In this paper, we consider Bayesian classifiers constructed on dissimilarity representations. We show that such classifiers are a feasible and reliable alternative for automatic classification of seismic signals. Our experiments were conducted on a dataset containing seismic signals recorded by two selected stations of the monitoring network at Nevado del Ruiz Volcano. Dissimilarity representations were constructed by calculating pairwise Euclidean distances and a non-Euclidean measure on the normalized spectra, which is based on the difference in area between spectral curves. Results show that even though Euclidean dissimilarities have advantageous properties, non-Euclidean measures can be beneficial for matching spectra of seismic signals. [ABSTRACT FROM AUTHOR]

This paper presents the results provided by the fine-scale thermohaline structure of near-surface layer (NSL) study done in the Colombian Pacific Ocean (CPO). Mathematical models for different regimes of the near-surface layer are formulated. Based on three stations, an hourly analysis of meteorological data, thickness change, temperature and salinity of this layer was done. The principles of formation of the thermohaline structure for NSL over CPO are related to night convection, wind-wave mixing, volume absorption of radiant energy and precipitation. [ABSTRACT FROM AUTHOR]

The aim of this little paper is to disseminate between regional geoscientists an historical data about an earthquake or swarm of earthquakes, felt in what is now the city of Medellín, in 1730. As far as is known, this event has not been reported before in available historical catalogs. It is important to understand the seismic hazard of the city and the region. An brief analysis is made with the limited published historical information. [ABSTRACT FROM AUTHOR]