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La investigación titulada "Saberes populares como estrategia para fortalecer la comprensión de textos matemáticos" se desarrolló con el objetivo de abordar una problemática educativa prevalente en Colombia: la comprensión lectora, específicamente en el ámbito de los textos matemáticos. Esta problemática es especialmente notoria en estudiantes tanto de zonas urbanas como rurales del municipio de Mompox, particularmente en las instituciones educativas Río Grande de la Magdalena y Normal Superior de Mompox, situadas en el departamento de Bolívar, a orillas de la depresión momposina. El estudio identificó que la principal causa de esta dificultad es la baja comprensión de los textos matemáticos. En respuesta, se propuso aprovechar la sabiduría popular y autóctona, integrándola en la pedagogía para mejorar la motivación y comprensión de estos textos en las mencionadas instituciones educativas. Durante la investigación, se detectaron varios factores relevantes que contribuyen a esta problemática, como la apatía hacia la lectura, especialmente en el área de matemáticas, y el escaso acompañamiento de padres y acudientes. Estos factores complican el proceso de comprensión y, en general, la formación académica integral de los estudiantes. La comprensión lectora permite relacionar los nuevos conocimientos con la realidad cotidiana. Por tanto, el desafío de esta investigación fue motivar a los estudiantes para que comprendieran los textos matemáticos y pudieran aplicarlos en su vida diaria, apoyándose en los saberes populares. El objetivo era que los estudiantes pudieran experimentar la aplicabilidad práctica de las matemáticas más allá del aula, integrando sus conocimientos académicos con su entorno sociocultural, sus costumbres y tradiciones tanto orales como escritas, y la realidad de sus comunidades.

BackgroundThere is very limited evidence on biomarkers for evaluating the clinical behavior and therapeutic response in rectal cancer (RC) with positive expression of cancer stem cells (CSCs).MethodsAn exploratory prospective study was conducted, which included fresh samples of tumor tissue from 109 patients diagnosed with primary RC. Sociodemographic, pathological and clinical characteristics were collected from medical records and survey. The OCT4 protein was isolated using the Western Blot technique. It was calculated the ΔCEA, ΔOCT4, and ΔOCT4/GUSB values by assessing the changes before and after chemotherapy, aiming to evaluate the therapeutic response.ResultsPatients had an average age of 69.9 years, with 55% (n=60) being male. Approximately 63.3% of the tumors were undifferentiated, and the most frequent staging classification was pathological stage III (n=64; 58.7%). Initial positive expression was observed in 77.1% of the patients (n=84), and the median ΔCEA was -1.03 (-3.82 - 0.84) ng/ml, with elevated levels (< -0.94 ng/ml) found in 51.4% of the subjects (n=56). Being OCT4 positive and having an elevated ΔCEA value were significantly associated with undifferentiated tumor phenotype (p=0.002), advanced tumor progression stage (p

La esteatosis no alcohólica es asociada con pronóstico benigno. Sin embargo, puede progresar a fibrosis, aunque no se comprende completamente el comportamiento de los genes que contribuyen a esta progresión. El objetivo de esta investigación fue analizar los indicios tempranos de fibrogénesis en la esteatosis no alcohólica en pacientes obesos frente a no obesos. Se realizó un estudio descriptivo prospectivo que incluyó a pacientes con esteatosis no alcohólica. Estos fueron divididos en dos grupos: obesos y no obesos. Se obtuvo información sociodemográfica, antropométrica y de padecimientos de componentes del síndrome metabólico. Se determinaron parámetros bioquímicos y niveles de expresión de los genes TNF-α, NF-kβ, CYP2E1, TGF-β, OPN, COL4α5 y HGF por RT-PCR. Los resultados muestran diferencias significativas en los niveles de expresión del gen CYP2E1, siendo mayor en pacientes obesos que padecían síndrome metabólico completo. Además, en pacientes no obesos sin componentes del síndrome metabólico se activa TGF-β como participante de vías fibrogénicas, y en pacientes obesos con síndrome metabólico completo el nivel de expresión significativo de CYP2E1 podría indicar una señal de alarma por un posible progreso de la enfermedad. Debe prestarse especial atención y seguimiento de la esteatosis en pacientes obesos.

Vehicle tires are high demand inputs in the transportation sector, however, at the end of their useful life they become a technical, economic, environmental and public health problem, due to their complex structure made up of various materials, especially vulcanized rubber. One possible way to mitigate the environmental impact of waste tires is to biodegrade rubber through the enzymatic action of fungi. The present study evaluated the biodegradation potential of waste rubber tires by enzymatic action of a white rot fungus (Pleurotus Ostreatus). Initially, the effect of the enzymatic action of the fungus on the mechanical structural and chemical properties of the rubber was evaluated. Sterilized tire rubber cuts of 1 cm2 were innoculated with the fungus. After 16 and 40 days, surface changes were evaluated by environmental scanning electron microscopy (ESEM). It was detected that the enzymatic action on the molecular bonds caused material erosion; changes in chemical structure by Fourier transform infrared spectroscopy (FTIR) were evaluated after 40 days. Also, potential of the scrap tire material to produce fungi biomass was analyzed, by preparing different concentrations of pulverized waste tire material in Agar Sabourad, and innoculating them with a suspension of the fungus mycelia. After 21 days, the germinated biomass at each substrate concentration was gravimetrically analyzed and modeled. Results showed a proportional dependence of the biomass growth as a function of the substrate concentration, and a potential of the white rot fungus to help biodegradation of waste tires.

Obtaining cellulose from agro-industrial waste offers the possibility of generating added value to solid biomass that is currently deposited in sanitary landfills. This research performed the evaluation of a residue from cocoa husk pods (Theobroma cacao L.), from the agricultural industry. The cellulose fiber was obtained through chemical treatments with KOH at 5% w/v to remove non-cellulosic components and then the fiber was bleached with 3% v/v hydrogen peroxide. The changes in chemical structure were determined through Fourier transform infrared spectroscopy (FTIR). The FTIR analysis confirms the progressive decrease of lignin and hemicellulose after applying chemical treatment. The morphological changes in the surface of the fiber were characterized using the SEM technique. The mass percentage of cellulose increases up to 68 %. It is expected that the Nano-Crystals (NCC) extracted from the biomass of the cocoa husk pods, present a high index of crystallinity and that they are also in suitable conditions to be useful as reinforcing agents in polymeric or mineral matrices, and may have potential application for technology transfer. Keywords: Nano-Crystals, cocoa, agro-industrial waste, biomass.

Copyright of Revista de Gastroenterología del Perú is the property of Sociedad de Gastroenterologia del Peru 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.)

Introducción: el carcinoma de células renales representa el 90% de las neoplasias malignas renales, siendo una de las variantes histológicas, el carcinoma de células renales cromófobas (CCRC). Su presentación clínica es inespecífica y generalmente es un tumor bien circunscrito, más frecuente en la sexta década de la vida y de buen pronóstico. Caso clínico: paciente femenina de 23 años con cuadro de hematuria intermitente más síntomas irritativos. Estudios imagenológicos mostraron masa nodular en polo inferior izquierdo de 33 x 36 mm de diámetro. Biopsia percutánea guiada por imagen, reportó CCRC. Se realizó nefrectomía parcial, con preservación del parénquima sano. La paciente ha presentado evolución satisfactoria. Conclusión: el CCRC es un subtipo histológico poco frecuente de carcinoma renal. Es importante a detección precoz y su presentación es en un amplio rango de edad, por lo que se sugiere sospecharlo en pacientes jóvenes con masa renal. Siendo un tumor bien delimitado, algunos casos pueden tratarse con nefrectomía parcial para conservar la función renal. Rev.cienc.biomed. 2015;6(1):160-164

Introducción: la matriz extracelular (MEC) es una red multifuncional, dinámica y compleja con propiedades biofísicas, mecánicas y bioquímicas específicas para cada tejido que, le confieren la capacidad de regular el comportamiento celular. Las células madre tienen un papel clave en el mantenimiento y regeneración tisular, se hallan en un microambiente específico, definido como nicho, en el que la MEC puede modular su proliferación, autorenovación y diferenciación. Objetivo: resaltar la función de la MEC en la regulación del comportamiento de las células madre y la labor de la interacción MEC-células madre en las propiedades y homeostasis del nicho en el que residen. Materiales y métodos: búsqueda electrónica en las bases de datos: PubMed, ScienceDirect, Scopus y Medline de artículos originales y de revisión en su mayor parte publicados entre 2008 y 2015. Resultados: se obtuvieron 150 artículos, de los que se utilizaron 44 documentos a conveniencia incluyendo artículos de revisión y artículos originales. Conclusión: la MEC es una red fundamental que orienta la diferenciación, proliferación y autorenovación de las células madre, al tiempo que ejerce una interacción de estas con los nichos donde residen. La función esencial de la MEC en la interrelación de las células madre con su nicho ha llevado al surgimiento de herramientas de la bioingeniería que abren posibilidades en la terapéutica, reparación y regeneración fisiológica de órganos. Rev.cienc.biomed. 2015;6(2):333-339

Introducción: los carcinomas uroteliales de tracto urinario superior primarios son tumores raros, representan el 5% de todos los cánceres uroteliales y menos del 10% de los tumores renales. Los síntomas son inespecíficos. Son más frecuentes en la 7-8º década de la vida. El pronóstico es pobre para los pacientes con enfermedad avanzada. Caso clínico: masculino de 55 años con hematuria microscópica y dolor lumbar. Ureterorrenoscopia flexible muestra sangrado difuso proveniente de las papilas de cáliz superior, asociado a lesión de características tumorales. Se realiza nefrectomía abierta izquierda con ureterotomía izquierda. Estudio anatomopatológico reportó carcinoma urotelial invasivo de tracto urinario superior. El paciente presentó evolución satisfactoria. Conclusión: el carcinoma urotelial del tracto superior es una enfermedad rara. Es importante la clasificación y estadificación preoperatoria precisa. El tratamiento de elección es la nefroureterectomía. Rev.cienc.biomed. 2015;6(2):364-368

Introduction: Alterations in the acid-base balance are studied in all medical specialties. Although most cases derive from a preexisting pathology, they can also manifest themselves in a primary context. The proper identification of the acid-base disorder allows the pathological process to be characterized. The correct interpretation of the blood gasometry as a technique for monitoring the ventilatory status, oxygenation and acid-base balance of a patient requires the integration of various physicochemical approaches in order to specify a diagnosis, quantify a therapeutic response, and monitor the severity or the progression of a pathological process. Methodology: A literature review was conducted in the PubMed, Scopus and Science Direct databases. The articles were selected according to the title and the abstract and sorted by topics relevant by pathophysiology, divergences, clinical approach, diagnosis, and management. Results: A guide the clinical correlation of the critical patient with the blood gasometry parameters to characterize the acid-base disorder through the proposition of a diagnostic algorithm. Conclusion: The incorporation of the three theories in a diagnostic algorithm facilitates a greater understanding of the pathophysiological mechanisms and allows us to identify a more precise therapeutic objective to correct the underlying disorder in the different clinical contexts of the patient.

As crude glycerol comprises a potential substrate for microalga fermentation and value added products’ biosynthesis, Auxenochlorella protothecoides was grown on it under heterotrophic and mixotrophic conditions and its growth kinetics were evaluated in a continuous system under steady state conditions. Increasing initial glycerol concentration (from 30 to 50 g/L) in the heterotrophic culture led to reduced biomass yield (Yx/S) and productivity (Px), but favored lipid accumulation. Under heterotrophic conditions, the microalga was found to grow better (biomass up to 7.888 g/L) and faster (higher growth rates), the system functioned more effectively (higher Px) and crude glycerol was exploited more efficiently. Heterotrophy also favored proteins synthesis (up to 53%), lipids (up to 9.8%), and carbohydrates (up to 44.6%) accumulation. However, different trophic modes had no significant impact on the consistency of proteins and lipids. Oleic acid was the most abundant fatty acid detected (55–61.2% of the total lipids). The algal biomass contained many essential and non-essential amino acids, especially arginine, glutamic acid, lysine, aspartic acid, leucine, and alanine. In all the experimental trials, the protein contents in the microalgal biomass increased with the increasing dilution rate (D), with a concomitant decrease in the lipids and carbohydrates fractions.

El presente trabajo se centra en mostrar, que, si bien es cierto que Colombia tiene en la región una larga trayectoria constitucional, es solo con la reforma de 1910 planteada por los republicanos, donde comienza a gestarse un verdadero y sólido estado de derecho en nuestro país, cuando esta reforma le otorga a la corte suprema la guarda de la constitución. La argumentación sobre la cual nuestra hipótesis descansa, es que esta reforma representa un paso importante en la historia jurídica del país en lo relativo a la independencia de las ramas del poder público en la consecución de sistemas de control que garanticen con mayor eficacia la coherencia del ordenamiento jurídico; y la consolidación de autoridad de la ciudadanía para definir los rumbos de su historia.

Synergy in anaerobic codigestion is described as positive interactions between a substrate and cosubstrate(s). Synergistic effects increase methane production over the weighted average methane production from monodigestion. Limited current knowledge defines synergy as a parameter in the plant control and design and in solving operational problems. In this study, synergy was determined in the anaerobic codigestion of chicken manure with industrial wastes (sugarcane molasses, cheese whey, and crude glycerol). A simplex lattice mixture design was used to determine mixing ratios. Synergy was assessed in terms of substrate composition and ammonia inhibition. The greatest synergistic effects were achieved with ternary mixtures. Synergy was also noticed when total ammonia nitrogen concentrations decreased and the organic load increased. Nonetheless, it was concluded that synergy could be reliably achieved when cosubstrate supplementation reduces ammonia inhibition and increases methane production as increases in organic load.

Copyright of Palobra is the property of Universidad de Cartagena 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.)

Introducción: La calidad de vida es un constructo multidimensional, comprende el bienestar de las personas y el grado de satisfacción con las circunstancias percibidas en la vida. Se ve afectada por la forma como cada persona hace frente a las situaciones cotidianas. El cuidador familiar constituye la base para provisionar cuidados a las personas con enfermedades crónicas, indispensables para que el paciente pueda vivir en comunidad, muchas veces sacrificando su salud por el bienestar de la persona que se cuida. Objetivo: Describir la calidad de vida de los cuidadores familiares de pacientes con enfermedad de Alzheimer que asisten a una institución de salud en Cartagena. Materiales y métodos: Estudio descriptivo, transversal. Se aplicó el instrumento “Calidad de vida de un miembro familiar que brinda cuidados a un paciente”, propuesto por Ferrell y Col a 61 cuidadores familiares, contemplando cuatro dimensiones de la Calidad de Vida (aspecto físico, psicológico, social y espiritual). Los puntajes mínimos equivalen a percepciones positivas de la calidad de vida en la dimensión física, social y espiritual, y para la dimensión psicológica los puntajes mínimos corresponden a percepción negativa. Resultados: La calidad de vida de los cuidadores familiares de pacientes con enfermedad de Alzheimer en forma general fue positiva (72,5%); resaltando positividad en el bienestar físico (68%) y social (51%), y negativo en las dimensiones psicológica (49,1%) y espiritual (46%). Conclusión: La calidad de vida de los cuidadores familiares de pacientes con Alzheimer que asisten a la institución de salud seleccionada para el estudio es positiva en las dimensiones física y social y negativa en las dimensiones espiritual y psicológica. Resaltando cambios en el dormir, aflicción y angustia frente al diagnóstico del paciente, miedo frente a una segunda enfermedad o recaída. Aspectos que podrían generar a mediano y largo plazo alteraciones en el estado de ánimo.

This study examines world scientific production on sustainable development on the basis of bibliometric indicators (scientific production, percentage variation of production, average cites per document, normalized impact, etc.) for the period 2007-2017. The analysis is made by country, by research institution, by art per millions of inhabitants and by gross domestic product, using Histcite database of scientific literature. The results show the total world production to have increased during the period studied, and that this topic has been attracting great scientific interest. Two groups of countries with high production are distinguished, one of which has highly specialized subject focus. There also three groups of countries with the major production compare articles per millions of inhabitants, which also have high impact.

Cassava is a shrub belonging to euphorbiaceous family, widely cultivated in South America, Africa and the Pacific because of its roots with starches of high nutritional value. There is a variety called Manihot utilissima or bitter cassava, which contains high concentrations of cyanogenic elements that make it unusable and poisonous raw material which avoided for human consumption, while the high concentrations of carbohydrates place it as a potential source of starch mainly for industrial use. The wet extraction method was used to get starch from bitter cassava (Manihot utilissima). A factorial (2x3) design was implemented for the experimental set up, with 2 levels of time and mincer speed and 2 for the temperature of H2O, with 2 independent replicates. The comparison with the dry extraction method was also studied, this method consists in drying the bitter cassava over night at 50°C. The yield of starch obtained in wet method ranged from 17.2 to 39.4 g of starch (mean of 26.6 g) obtained from the original samples of 250 g of wet bitter cassava, yielding yields ranging from 6.88 to 15.76% (average 10.64%) of the dry mass. The results were then analysed using PAST software v3.16 for ANOVA statistical evaluation, trend and Pareto were used to determine optimal conditions for the extraction of starch by wet and dry methods. Once the assumptions for analysis of variance (ANOVA) were made, it was concluded that a higher yield of starch is obtained from lower speeds and time, whereas the temperature of H2O is not significant for the process, giving as optimal value for wet method = 0.0678762 for 1/x of the yield of starch obtained, with a starch purity of 64.90% ± 1.21% ranging up to 85.37% ± 1.42%. The extraction of bitter cassava starch has demonstrated its potential for the use of this variety of cassava which generates an added value to the product.

Agriculture modernization and biomass processing generate millions of tons of waste per year containing different amounts and quality of polymeric components such as starch, sugar, lignin, cellulose and hemicellulose. The raw material for extraction was the green plantain peel (Musa paradisiaca), obtained from a local company that produces fried plantain snacks. This work presents the comparisons between the synthesis by wet extraction method and the modification of natural biopolymer with polyhydric alcohol (glycerin). Four blends were prepared at different concentrations of starch, glycerin and water to create a modified biopolymer. Later they were characterized with Fourier Transform Infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and Amylose-Amylopectin ratio. In the unmodified starch samples, the observed bandwidth at 3373 cm-1 can be attributed to amylopectin O-H stretching (55%) and its width was attributed to the formation of inter- and intramolecular hydrogen bonds, also in the region known as the fingerprint (close IR), ranging from 400 to 1250 cm-1, four characteristic peaks are observed in the spectra between 520 and 1020.16 cm -1, which are attributed to the stretching of the C-O bond. For both unmodified starch and modified starch, the TGA tests showed that the weight loss started at a temperature of about 310 °C, but in modified starch the total degradation temperature increases to about 610 °C. Starch extraction from plantain peel wastes has demonstrated its potential for waste use and the production of value-added products, like degradable polymers. The mixtures of starch, glycerin and water (labeled 1, 2, 3, and 4) have different characteristics, shown in the FTIR spectra. Mixture number 4, with 35% glycerin, has a significant peak at 3425 cm-1, corresponding to the OH group stretching. The bending peak at 1641 cm-1, has less transmittance, since the percentage of water in the mixture is zero. The transmittance band between 1060 and 990 cm-1, is characteristic of the polysaccharides, of amorphous structure.

Introduction: the primary upper urinary tract urothelial carcinomas are rare tumors, they represent 5% of all urothelial cancers and less than 10% of kidney tumors. The symptoms are nonspecific. They are more common in the seventh or eighth decade of life. The prognosis is poor for patients with advanced disease. Case report: a 55 years old man with microscopic haematuria and lumbar pain. Supple ureterorenoscopy shows bleeding in napa that comes from papillae of upper calyx associated with tumor lesion characteristics. Open left nephrectomy with left urethrotomy was performed. Pathological study reported invasive upper urinary tract urothelial carcinoma. The patient presented satisfactory evolution. Conclusion: the upper tract urothelial carcinoma is a rare disease. It is important classification and accurate preoperative staging. The treatment of choice is nephroureterectomy. Rev.cienc.biomed. 2015;6(2):364-368 KEYWORDS Urothelial carcinoma; Kidney Pelvis; Radical nephroureterectomy; Ureteroscopy.

Introduction: extracellular matrix (ECM) is a multifunctional network, dynamic and complex with specific biophysics, mechanic, and biochemical properties for each tissue, which function is to regulate the cellular behavior. Stem cells play an important role in the tissue maintenance and regeneration and they are found in a specific microenvironment, defined as niche, in which the ECM can modulate the proliferation, self-renewal and differentiation. Objective: to highlight the function of the ECM in regulating the stem cells behavior and the labor of the ECM-stem cell interaction in the properties and homeostasis of the niche in which they reside. Material and methods: electronic search in the databases: PubMed, ScienceDirect, Scopus and Medline of review and original articles mostly published between 2008 and 2015. Results: 150 articles were obtained, from which 44 documents were used for convenience including review articles and original articles. Conclusion: ECM is a fundamental network that guides the differentiation, proliferation and self-renewal of stem cells, while exerting interaction of these cells with the niches where they reside. The key role of ECM in the interrelation of stem cells with their niche has led to the emergence of bioengineering tools that open up possibilities in the therapy, repair and physiological regeneration of organs. Rev.cienc.biomed.2015;6(2):333-339 KEYWORDS Extracellular matrix; Stem cell; Stem cell niche; Bioengineering; Hematopoietic stem cells.

Background: There is very limited evidence on biomarkers for evaluating the clinical behavior and therapeutic response in rectal cancer (RC) with positive expression of cancer stem cells (CSCs). Methods: An exploratory prospective study was conducted, which included fresh samples of tumor tissue from 109 patients diagnosed with primary RC. Sociodemographic, pathological and clinical characteristics were collected from medical records and survey. The OCT4 protein was isolated using the Western Blot technique. It was calculated the DCEA, DOCT4, and DOCT4/GUSB values by assessing the changes before and after chemotherapy, aiming to evaluate the therapeutic response. Results: Patients had an average age of 69.9 years, with 55% (n=60) being male. Approximately 63.3% of the tumors were undifferentiated, and the most frequent staging classification was pathological stage III (n=64; 58.7%). Initial positive expression was observed in 77.1% of the patients (n=84), and the median DCEA was -1.03 (-3.82 - 0.84) ng/ml, with elevated levels (< -0.94 ng/ml) found in 51.4% of the subjects (n=56). Being OCT4 positive and having an elevated DCEA value were significantly associated with undifferentiated tumor phenotype (p=0.002), advanced tumor progression stage (p <0.001), and negative values of DOCT4 (p <0.001) (suggestive of poor therapeutic response) compared to those without this status. Conclusion: This study identified a significant and directly proportional association among the values of DCEA, DOCT4, and DOCT4/GUSB. These findings suggest that DCEA holds potential as a clinical biomarker for determining the undifferentiated tumor phenotype, advanced clinical stage, and poor therapeutic response in RC with CSCs positive expression. [ABSTRACT FROM AUTHOR]

Introduction: the renal cell carcinomas represent 90% of all malignant renal tumors, being the chromophobe renal cell carcinoma (CRCC) a histological variant. Its clinical presentation is unspecific and generally it is a well-circumscribed tumor, with major prevalence in the sixth decade of life and with good prognostic. Case report: 23-year-old female patient with symptomatology of intermittent hemorrhage and irritating symptoms. The imagenological studies reported nodular mass in the left inferior side of 33 x 36 mmm of diameter. The image-guided percutaneous biopsy showed CRCC. And a partial nephrectomy with preservation of the healthy side was carried out. The patient had satisfactory evolution. Conclusion: the CRCC is an uncommon histological subtype of renal carcinoma. Its early detection is important and its symptomatology occurs in a wide age group, thus it must be suspected in young patients with renal mass. Due to it is a delimited tumor, in some cases, it could be treated with partial nephrectomy to preserve the renal function. Rev.cienc.biomed. 2015;6(1):160-164 KEYWORDS Kidney neoplasms; Hematuria; Nephrectomy.

One of the most important factors in the redox state of chromium in solution is pH, which, according to its value, can lead to oxidation of Chromium (III) to Chromium (VI). The presence of Chromium (VI) in natural waters is related to discharges from anthropogenic activities, such as leather industry, electroplating, paints, among others. The Chromium (VI) the most important toxicologically, the present state chromates, dichromates and chromic acid . The International Agency for Research on Cancer (IARC) has classified Chromium (VI) in group 1 (carcinogenic to humans) and metallic Chromium and Chromium (III) in Group 3 (not classifiable as to its human carcinogenicity. In Colombia, the permissible exposure values reported by the District Department of Health of Bogota for the general population are up to 10 µgL-1and population exposed up to 20 µgL-1 and the Colombian Technical Standard (NTC 813) indicates as maximum in drinking water, a concentration of 50 µgL-1. In order to study the behavior of Chromium (VI) and pH in solution in marine ecosystems it was carried out systematic type sampling in a square mesh for data variables involved in the Ciénaga de las Quintas magrove swamp, which belongs to the internal waters system of Cartagena de Indias’ Bay, Colombia. 35 field samples were taken in amber glass bottles, adjusting the pH with nitric acid, for further analysis by the Cr method 3500 B. For the pH parameter values were taken in field with a portable pH meter. The exploratory analysis showed that the concentration data for Chromium (VI) did not conform to normal, so underwent a transformation to work with the LOG base 10, for adjustment to normal (S.W., p>0.05), with an average value of 3.23 µgL-1. In contrast, the pH has a homogenous distribution behavior (C.V. = 1.52%) with a mean value of 8.16 µgL-1; making it representative for the system. The pH values are adjusted to normal without needing any adjustment needed (S.W.; p>0.05). To make the structural analysis, with the aim of demonstrating spatial autocorrelation of variables, the Index of Moran (Moran, 1950) was used, which varies between 1 and -1. The pH showed slight spatial relationship or a structure related to a concentration gradient. On the other hand, the concentration of Chromium (VI) showed spatial autocorrelation, the most likely structure is the gradient type.

In Colombia, the production of cocoa beans is an important export business classified as “fine cocoa” type by the International Cocoa Organization (ICCO). Drying for agricultural products is one of the most cost-effective applications of solar energy and the drying methods for cocoa beans are traditional and vary with geographical locality. Cocoa beans are dried after fermentation in order to reduce the moisture content, being the open-air solar drying (direct solar dryer) and the greenhouse drying (plastic roof solar dryer) two methods used in colombian rural areas. However, in the Caribbean region of Colombia is widely used, by rural farmers, the open-air solar drying. This method is economic but susceptible to contamination with foreign materials, insects and rodents, affecting the quality of the beans. This work presents the construction of a plastic roof solar dryer for drying cocoa beans in a farm that use direct solar dryer. The moisture content of the cocoa beans were determined using a MB 45 Halogen Ohaus moisture analyzer. The moisture content was reduced from 58 % to 7 % in 6 d for the open-air solar drying (drying constant, k = 0.76 d-1), while the greenhouse drying took only 4 d (drying constant, k = 1.68 d-1) and produced better quality cocoa beans, protected from direct solar radiation, environmental pollution and animal contact. Technical and economical results indicate that greenhouse drying is feasible for rural farmers in the Caribbean region of Colombia.