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The sustainability of food value chains is affected by the large amounts of waste produced with a high environmental impact. Food waste valorization applying the biorefinery concept has emerged as an alternative to reduce the generation of greenhouse gases and to promote the socio-economic development of value chains at local, regional, and national levels. This paper analyzes the sustainability of food waste biorefineries designed for boosting rural economic development in Colombia. These biorefineries were designed following a strategy based on a portfolio of bioprocesses involving fractions based on the composition of the raw materials. The valorization of six food residues produced in three representative rural areas of Colombia (i.e., Chocó, Caldas, and Sucre) was analyzed. Acai, annatto, sugarcane bagasse, rejected plantain and avocado, and organic kitchen food waste (OKFW) were selected as food wastes for upgrading. The biorefinery design strategy comprised five steps for filtering the most promising bioprocesses to be implemented. The OKFW was analyzed in detail, applying the design strategy to provide a step-by-step guide involving a portfolio of bioproducts, the technological maturity index, and the socio-economic context. This strategy implementation for OKFW valorization resulted in a scenario where biorefineries with levulinic acid production were the most feasible and sustainable, with high techno-economic performances and low environmental impacts. For the valorization of the other food residues, the processes with the greatest feasibility of being implemented in rural areas were bioactive compounds, oil, flour, and biogas production. [ABSTRACT FROM AUTHOR]

The variability of potato cultivars and environments in the production area of Nariño-Colombia, demands the adjustment of agronomic recommendations for the improvement of crop management. Physiological behavior and yield of four short-cycle potato cultivars were evaluated: Solanum tuberosum Phureja groups (Mambera, Ratona Morada and Criolla Colombia) and Andigena (Morasurco), under three environments, characterized edaphoclimatically (AH1, AH2, and AH4) and three fertilization levels. The yield components did not present differences between these levels, except for AH2, where level 3 surpassed the others in yield, and AH3 for harvest index with differences between levels. Regarding the cultivars, there were statistical differences in all environments; the highest yield was obtained by Ratona Morada and Mambera in AH4, Criolla Colombia in AH1, and a homogeneous behavior for Morasurco in all environments. In AH1 and AH2 the physiological indexes were similar in proportion and occurrence, while in AH4 the behavior was variable, with higher values in Morasurco and Mambera. ANOVA and discriminant analysis of principal components (DAPC) differentiated Morasurco from Phureja cultivars and Criolla Colombia from Ratona and Mambera. The grouping of environments in the DAPC ratifies the classification of the environments. The nutritional requirements of the genotypes can be limited by elements different from those evaluated; the productivity was mainly influenced by the environments; Mambera and Ratona Morada are established as alternatives in the AH4 environment, and Criolla Colombia and Morasurco in the other environments. [ABSTRACT FROM AUTHOR]

Contextualization: In the coffee production system, the seedling stage is a determining factor in the success of the implementation and behavior of the crop. In this stage, the nutrition is a very relevant factor. Knowledge gap: The use of substrates with diverse origins for the implementation of seedbeds in coffee makes difficult a correct diagnosis of fertility. For this reason, the nutrition in this phase of the productive system is based on recommendations and generalized formulas, that do not consider the differential needs of the varieties used and their state at the time of transplantation. Purpose: The objective of this research was: evaluating the effect of Urea, DAP and KCl fertilizers and mixtures of these on the growth of coffee seedlings (variety Castillo) during the seedling stage. Methodology: The work was carried out in 2019, at the farm La Quinta, in the municipality of Consacá (Nariño-Colombia), at 1.650 meters above sea level, using a completely randomized design with eight treatments and eight repetitions distributed this way: 2.17g of Urea + 0.7g of DAP; 4.3g of DAP; 3.3g of KCl; 0.6g of Urea + 4.3g of DAP; 2.1g of Urea + 3.3g of KCL; 4.3g of DAP + 3.3g of KCl; 2.1g of Urea + 4.3g of DAP + 3.3g of KCl and a control without application. It was carried out an analysis of variance with these variables: height, number of leaves, dry and fresh weight of the seedlings, besides a functional growth analysis with biweekly evaluations. Results and conclusions: The treatment with DAP presented the highest height (20.65cm), greater fresh and dry weight of stem (3.86g; 1.43g), greater total dry weight (5.33g) greater leaf area (350.8cm2) and leaf area index (0.99). The Treatment with Urea + DAP showed better net assimilation rate (0.00029g cm d) and better crop growth rate (2.87e g cm d). The Treatment with DAP and KCl reached the highest value for relative growth rate (0.047g g d). In all cases, phosphorus became conclusive for the seedling stage, due to its presence was related to superior physiological behavior. [ABSTRACT FROM AUTHOR]

Copyright of Revista Facultad Nacional de Agronomía Medellín is the property of Universidad Nacional de Colombia 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 Ensayos de Economia is the property of Universidad Nacional de Colombia 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 study investigates the technical, economic and environmental performances for producing ethanol and furfural from Pinus patula bark, on a biorefinery concept. This was done through experimental, techno-economic and environmental assessments. The experimental analysis considered the physicochemical characterization of the raw material and three pre-treatment methods: (i) dilute acid, (ii) alkali, and (iii) liquid hot water. The alkali method showed the highest yield (50%) and the pentose rich hydrolysate was used to produce furfural (yield 91%). The solid from the pre-treatment stage was enzymatically hydrolyzed (max. concentration 63 g/l), and the hexose rich solution was used as substrate for producing ethanol (0.42 g ethanol/g sugars). The obtained experimental yields were used as the basis to build a process model to generate mass and energy balances, from which the techno-economic and environmental assessments are derived. Based on different levels of heat integration, three scenarios were assessed: (Sc.1) non-integrated, (Sc.2) fully energy integrated and (Sc.3) fully integrated plus cogeneration scheme. Results revealed that by increasing the level of energy integration, the biorefinery system can be profitable with a positive net present value (Sc.3: 184.54 M.USD/y) and a payout period within the project׳s life-time (Sc.3: 2.22 y). The annualized production costs can be decreased up to 84% and 66% for scenario 3 in comparison with scenarios 1 and 2, respectively. From the environmental point of view, the biorefinery system is positively affected by increasing the level of energy integration. The potential environmental impact can be reduced up to 74% and 66% for scenario 3, in comparison with scenarios 1 and 2, respectively. [ABSTRACT FROM AUTHOR]

Background: The burnout syndrome is defined as an inadequate response to chronic job stressors. In the last years the burnout syndrome has acquired importance. Materials and methods: A cross-sectional study was designed to evaluate the prevalence and psychosocial factors associated with the burnout syndrome in family doctors and specialists which work in several institutions in Manizales, Caldas, and Virginia, Risaralda. The questionnaire evaluated demographic factors, prevalence of burnout syndrome, family functioning and personal relationships. Results: 227 physicians were evaluated, (132 family and 95 specialists). A burnout frequency was found of 17.6%, 26.4% with high exhaustion, 26.1% presented depersonalization and 7.2% of low personal fulfillment. A significant relationship between burnout and extra work activity was found (p = 0.039), observing that the burnout syndrome occurs in 25.8% of physicians who do not perform any activity outside work during the week and in 14.3% of the physicians who engaged activities outside work. A significant relation (p = 0.009) was also found with family functioning, observing that 37.5% of the physicians who have moderate dysfunction tend to present burnout syndrome. Conclusions: The burnout syndrome is common in this population, and is related to family functioning and the number of hours dedicated to activities outside work. [ABSTRACT FROM AUTHOR]

Copyright of CES Medicina Veterinaria & Zootecnica is the property of Universidad CES 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 article reports the results seen from adjusting a model of non-observable components to the monthly electrical power demand in Colombia from 1995:8 to 2006:1 in order to separate the underlying tendency of the periodical component associated with the annual cycle and study its behavior. Findings show that the periodical component has a stochastic behavior but such behavior does not broaden with an increased level in the series; likewise, the model indicates that the monthly growth in demand has a linear deterministic component, approximately constant during recent years, whose rises and falls have coincided with the rises and falls seen in the GDP. [ABSTRACT FROM AUTHOR]

This study shows a techno-economic and environmental assessment of the extraction of essential oil from Oregano and Rosemary in Colombian. Experiments were carried out using water distillation technology with extraction yields of 8.14 kg/tonne and 8.43 kg/tonne for Oregano and Rosemary, respectively. The samples were analyzed to determine the essential oil composition and use this data as starting point in the technical analysis. Three extraction technologies ( i.e. , supercritical fluid, solvent, and water distillation) were modeled and assessed. The effect of energy integration was considered by assessing two scenarios per technology ( i.e. , without integration, full integration). In the case of Oregano, the lowest production costs were obtained for extraction by supercritical fluids with full energy integration (6.71 USD/kg). In the case of Rosemary, the lowest production costs were those for fully integrated water distillation technology (6.57 USD/kg). For both Oregano and Rosemary, the lowest potential environmental impact (Oregano: 0.018 PEI/kg, Rose: 0.016 PEI/kg) and carbon footprint (Ore: 0.80 kg CO 2 -e/kg oil, Rose: 0.78 kg CO 2 -e/kg oil) were those for water distillation with full energy integration. [ABSTRACT FROM AUTHOR]

Highlights: [•] Techno-economic analysis of biorefineries based on five oleochemical feedstocks in Colombia. [•] Environmental potential impact assessment of each biorefinery scenario. [•] Analysis of technologies and scenarios for different transformation routes. [•] Comparison and discussion of each feedstock transformation option. [Copyright &y& Elsevier]

Highlights: [•] Modeling and simulation of essential oil extraction from Citronella and Lemongrass. [•] Analysis of supercritical fluid, solvent, and water distillation extraction. [•] Influence of energy integration on total energy consumption. [•] Techno-economic and environmental assessment to evaluate the most promising configuration. [ABSTRACT FROM AUTHOR]

Highlights: [•] Simulation of two technological conversion schemes based on Oil Palm. [•] Techno-economic assessment to evaluate the most promising scheme. [•] Comparison of each scheme from the potential environmental impact point of view. [ABSTRACT FROM AUTHOR]

Highlights: [•] Experimental characterization of four lignocellulosic raw materials. [•] Modeling and simulation of fuel ethanol production from four lignocellulosic raw materials. [•] Techno-economic assessment to evaluate the most promising feedstock. [ABSTRACT FROM AUTHOR]

Pinus Patula is widely distributed in Colombia and has become a useful timber specie for reforestation programs. Forest biomass can be used to produce directly hydrogen through thermochemical technologies (e.g. gasification). The aim of this work is to assess the environmental impact of hydrogen production via gasification using P. patula as raw material. The life cycle assessment was carried out considering a cradle-to-gate perspective starting at the seedlings production and finishing at the hydrogen production. Inventory data of the forest system was obtained from a plantation located in Manizales, Colombia and additional data were provided with bibliographic resources. Mass and energy balances for hydrogen were obtained from the software Aspen Plus V8.0. The seedling production and P.patula cultivation were identified as hotspots of the hydrogen production. Agrochemicals application and seedbeds materials have the highest contribution to most of the environmental impacts in the seedlings production system. In the P. patula cultivation system, the fertilizer application and the collection/transportation of wood generate the highest emissions. The rotation periods of the cutting cycles strongly influence the agrochemicals dosage depending on the wood final purpose. The use of diesel in the collection/transportation of wood has an important share of the total environmental impact. [ABSTRACT FROM AUTHOR]

The use of agricultural residues for bioenergy production is gaining importance at a global scenario. There are multiple options to convert these residues into bioenergy carriers such as thermochemical processes (e.g., gasification). In this paper, a techno-economic assessment is carried-out to compare the stand-alone and biorefinery production of hydrogen through gasification as potential scenarios for bioenergy production. Experimental gasification procedures were carried out aiming to determine initial conditions and parameters for the simulation approach. The results demonstrated that the production of hydrogen based on the concept of a biorefinery can improve the profitability of the processes compared to that based on the stand-alone way. Thermochemical processes seem to be a potential technology for bioenergy production in Colombia; however, it also needs to be benchmarked with other technologies in order to provide insights on future development of bioenergy programs in Colombia. [ABSTRACT FROM AUTHOR]

Objective: The suicide attempt has a multifactorial character which is an element of great importance for Public Health in order to prevent its fatal ending. This way, the suicidal attempt in patients of the Institute of the Nervous System in Pereira (Risaralda, Colombia) from 2013 to 2014 is characterized. Methodology: This is a retrospective cross-sectional, analytical study that includes 73 medical records of people aged 12 years or older with a record of hospitalization, and who have tried to commit suicide. Incomplete medical records and organic mental disorders are excluded. Results: The female sex with 60.3% was the most frequent; the average age is 33.16 ± 16.1 years. The most commonly used suicide attempt mechanism is drugs with 45.2%; the residence with 69.7% is the place where most self-harm behaviors are committed; also, family conflict is the most frequent precipitating factor with 42.6%. The single population represents 58.9%, marijuana is the psychoactive drug with the highest consumption with 21.9% and depression is the most frequent psychiatric disorder with 61.8%. Conclusions: The drugs for suicide attempt keep being the first non-lethal self-harm method; the place to commit suicide is the residence and its main precipitating factor is family conflict. In this study was found a greater proportion of events between the ages of 21 and 65, which differs from other records in which this event is more frequent in teenagers. It is important to know the variables that characterize the suicide attempt, in order to generate a greater impact on at-risk categorized population. [ABSTRACT FROM AUTHOR]

In this paper, fuelethanol production from Chlorella vulgariscake wasevaluated by experimental and conceptual design techniques.Enzymatic hydrolysis and fermentation with Saccharomyces cerevisiaewas performed to quantify the reducing sugars and ethanol from microalgaecake. Extractive distillation and molecular sieves were evaluatedas alternative technologies for the dehydration of ethanol. The massand energy balances were solved using the Aspen Plus software. Thetotal ethanol production costs were evaluated using the Aspen ProcessEconomic Analyzer software, and the Waste Reduction algorithm (WAR)was used to calculate the environmental impacts. Additionally, theeffect of energy integration was included in the economic analysisand environmental assessment. The yields obtained for reducing sugarsand ethanol were 0.55 and 0.17 g per g of cake, respectively. Theglobal yield of ethanol was 211.9 L per tonne of cake, and the totalproduction cost was 0.76 and 0.91 USD per liter using molecular sievesand extractive distillation, respectively. The most promising technologyto produce ethanol from microalgae cake was dehydration by molecularsieves with full energy integration. For this technology, the productioncost was 0.76 USD per liter, which resulted in an economic marginof 19.15%. From the environmental point of view, the potential environmentalimpact was 0.84 PEI/kg products. Additionally, bioethanol from microalgaewas shown to be less harmful than bioethanol from corn and sugar cane. [ABSTRACT FROM AUTHOR]

In this paper a techno-economic analysis for a sugarcane biorefinery is presented for the Colombian case. It is shown two scenarios for different conversion pathways as function of feedstock distribution and technologies for sugar, fuel ethanol, PHB, anthocyanins and electricity production. These scenarios are compared with the Colombian base case which simultaneously produce sugar, fuel ethanol and electricity. A simulation procedure was used in order to evaluate biorefinery schemes for all the scenarios, using Aspen Plus software, that include productivity analysis, energy calculations and economic evaluation for each process configuration. The results showed that the configuration with the best economic, environmental and social performance is the one that considers fuel ethanol and PHB production from combined cane bagasse and molasses. This result served as the basis to draw recommendations on technological and economic feasibility as well as social aspects for the implementation of such type of biorefinery in Colombia., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

In this work, the hierarchical decomposition methodology was used to conceptually design the production of fuel ethanol from sugarcane. The decomposition of the process into six levels of analysis was carried out. Several options of technological configurations were assessed in each level considering economic and environmental criteria. The most promising alternatives were chosen rejecting the ones with a least favorable performance. Aspen Plus was employed for simulation of each one of the technological configurations studied. Aspen Icarus was used for economic evaluation of each configuration, and WAR algorithm was utilized for calculation of the environmental criterion. The results obtained showed that the most suitable synthesized flowsheet involves the continuous cultivation of Zymomonas mobilis with cane juice as substrate and including cell recycling and the ethanol dehydration by molecular sieves. The proposed strategy demonstrated to be a powerful tool for conceptual design of biotechnological processes considering both techno-economic and environmental indicators., (Copyright © 2011 Elsevier Ltd. All rights reserved.)