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1.
Nature ; 591(7850): 379-384, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33731946

RESUMEN

Artificial intelligence (AI) is defined as the ability of machines to perform tasks that are usually associated with intelligent beings. Argument and debate are fundamental capabilities of human intelligence, essential for a wide range of human activities, and common to all human societies. The development of computational argumentation technologies is therefore an important emerging discipline in AI research1. Here we present Project Debater, an autonomous debating system that can engage in a competitive debate with humans. We provide a complete description of the system's architecture, a thorough and systematic evaluation of its operation across a wide range of debate topics, and a detailed account of the system's performance in its public debut against three expert human debaters. We also highlight the fundamental differences between debating with humans as opposed to challenging humans in game competitions, the latter being the focus of classical 'grand challenges' pursued by the AI research community over the past few decades. We suggest that such challenges lie in the 'comfort zone' of AI, whereas debating with humans lies in a different territory, in which humans still prevail, and for which novel paradigms are required to make substantial progress.


Asunto(s)
Inteligencia Artificial , Conducta Competitiva , Disentimientos y Disputas , Actividades Humanas , Inteligencia Artificial/normas , Humanos , Procesamiento de Lenguaje Natural
2.
Environ Res ; 248: 118003, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38163544

RESUMEN

Hydrogen is a key energy vector to accomplishing energy transition and decarbonization goals proposed in the transport and industrial sectors worldwide. In recent years, research has focused on analyzing, designing, and optimizing hydrogen production, searching to improve economic prefeasibility with minimal emissions of polluting gases. Therefore, the techno-economic analysis of hydrogen production by electrolytic and gasification processes becomes relevant since these processes could compete commercially with industrial technologies such as SMR - Steam methane reforming. This work aims to analyze hydrogen production in stand-alone processes and energy-driven biorefineries. The gasification and electrolysis technologies were evaluated experimentally, and the yields obtained were input data for scaling up the processes through simulation tools. Biomass gasification is more cost-effective than electrolytic schemes since the hydrogen production costs were 4.57 USD/kg and 8.30 USD/kg at an annual production rate of 491.6 tons and 38.96 tons, respectively. Instead, the electrolysis process feasibility is strongly influenced by the recycled water rate and the electricity cost. A sensitivity analysis was performed to evaluate the temperature, pressure, and current density variability on the hydrogen production rate. The increase in pressure and current density induces parasitic currents while the temperature increases hydrogen production. Although higher hydrogen production rates from gasification, the syngas composition decreases the possibility of being implemented in applications where purity is critical.


Asunto(s)
Gases , Vapor , Biomasa , Hidrógeno , Electrólisis
3.
Molecules ; 28(3)2023 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-36770944

RESUMEN

Biorefinery feasibility is highly influenced by the early design of the best feedstock transformation pathway to obtain value-added products. Pretreatment has been identified as the critical stage in biorefinery design since proper pretreatment influences subsequent reaction, separation, and purification processes. However, many pretreatment analyses have focused on preserving and valorizing six-carbon sugars for future use in bioconversion processes, leaving aside fractions such as hemicellulose and lignin. To date, there has been no pretreatment systematization for the removal of lignocellulosic fractions. This work defines pretreatment efficacy through operational, economic, environmental, and social indicators. Thus, using the data reported in the literature, as well as the results of the simulation schemes, a multi-criteria weighting of the best-performing schemes for the isolation or removal of cellulose, hemicellulose, and lignin was carried out. As a main result, it was concluded that dilute acid is the most effective for cellulose isolation and hemicellulose removal for producing platform products based on six- and five-carbon sugars, respectively. Additionally, the kraft process is the best methodology for lignin removal and its future use in biorefineries. The results of this work help to elucidate a methodological systematization of the pretreatment efficacy in the design of biorefineries as an early feasibility stage considering sustainability aspects.


Asunto(s)
Celulosa , Lignina , Lignina/metabolismo , Biomasa , Celulosa/metabolismo , Azúcares , Hidrólisis
4.
Molecules ; 28(20)2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37894505

RESUMEN

The methanation of CO2 is of great interest in power-to-gas systems and contributes to the mitigation of climate change through carbon dioxide capture and the subsequent production of high-added-value products. This study investigated CO2 methanation with three Ni catalysts supported on Al2O3 and ZrO2, which were simulated using a mathematical model of a packed bed reactor designed based on their chemical kinetics reported in the literature. The simulated reactive system was fed with syngas obtained from residual coffee pulp obtained after a solvent phytochemical extraction process under several gasification conditions. The results reflect a high degree of influence of the catalyst support, preparation method, and syngas composition on CO2 and H2 conversions and CH4 selectivity. For all the syngas compositions, the Ni/ZrO2 catalysts showed the best values for CO2 conversion and H2 conversion for the Ni/Al2O3 catalyst except in gasification at 700 °C and using the Ni/ZrO2p catalyst.

5.
J Fish Biol ; 96(6): 1444-1453, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32166742

RESUMEN

Hyphessobrycon chiribiquete n. sp. is described from the Río Caquetá drainage in Colombia and the Río Ucayali drainage in Peru, western Amazon. The new species is diagnosed from its congeners by having the following combination of characters: a conspicuous narrow midlateral stripe, starting on the sides of the body behind the opercle near the lateral line; lateral stripe overlapped anteriorly with a vertically elongated humeral blotch; inner premaxillary teeth pentacuspid; margin of anal fin falcate in mature males.


Asunto(s)
Characidae/anatomía & histología , Characidae/clasificación , Aletas de Animales/anatomía & histología , Animales , Colombia , Masculino , Perú , Ríos
6.
Rev Biol Trop ; 64(2): 715-32, 2016 Jun.
Artículo en Español | MEDLINE | ID: mdl-29451765

RESUMEN

Ecological studies of species, such as the stomach content analysis, allow us to recognize different trophic groups, the importance of trophic levels and the interrelationships among species and other members of the community. In this investigation, we studied food habits, feeding variation and trophic relationships of the fishes present in streams of the Corral de San Luis drainage, Tubará, Atlántico Department, a part of the lower Magdalena River Basin in Colombian Caribbean. Fish samples of Awaous banana, Agonostomus monticola, Andinoacara latifrons, Hyphessobrycon proteus, Poecilia gillii, Gobiomorus dormitor and Synbranchus marmoratus were obtained using a seine (2x5 m, mesh 0.5 cm), from November 2012 to October 2013. To analyze their stomach contents, we used numeric (% N), volumetric (% V) and frequency of occurrence (% FO) methods, an emptiness coefficient (C.V), index of food item importance (I.A). Besides, physical and chemical habitat parameters were recorded on site. Information obtained was processed using multivariate statistical analysis, ecological indices, and null models: canonical correspondence analysis (CCA), principal component analysis (PCA), trophic niche amplitude (Shannon-Weaver H´) and trophic overlap (Morisita-Horn). We observed significant differences on food resources consumption (K-W= 20.86; p<0.05) among the studied species. They were classified according to their food habits as omnivores with a tendency towards insectivory (A. monticola H´0.60; A. latifrons H´0.43), herbivores with a tendency towards the consumption of algae (A. banana H´0.50; P. gillii H´0.54) and carnivores with a tendency towards insectivory (H. proteus H´0.23); benthic invertebrates and microalgae were found the most important food sources. A total of 65 food items were identified in this study: 21 for A. banana (2 unique, 19 shared), 40 for A. monticola (21 unique, 19 shared), 19 for A. latifrons (5 unique, 14 shared), 6 for H. proteus (1 unique, 5 shared) and P. gillii with 28 (4 unique, 24 shared). The canonical correspondence analysis showed that water conductivity, salinity and pH were the variables that directly influenced fish community structure at the sampled sites. The null model analyses showed that the group of fishes was significantly segregated (p= 0.001) along the trophic axis, with respect to shared food items, and that the segregation was not influenced or generated by competition. The Morisita-Horn index showed false trophic overlap (similarity of about 80 %) between A. banana and P. gillii. The first component of the PCA analysis was explained mainly by phytoplankton, and component two was correlated with items of animal origin. The fishes associated with PC1 were P. gillii and A. banana, with high ingestion values of microalgae. PC2 was explained by A. monticola with high numbers of food items of animal origin. The group of fishes studied behaved as an assemblage; given that the trophic interrelationships showed false trophic overlap, and that they did not exclude one another from the ecosystems, but instead, used different food resources and different physical spaces within their habitat.


Asunto(s)
Conducta Alimentaria/fisiología , Peces/fisiología , Cadena Alimentaria , Animales , Región del Caribe , Colombia , Peces/clasificación , Contenido Digestivo , Ríos , Estaciones del Año
7.
Artículo en Inglés | MEDLINE | ID: mdl-38592628

RESUMEN

Biosurfactants have been profiled as a sustainable replacement for chemical-based surfactants since these bio-based molecules have higher biodegradability. Few research papers have focused on assessing biosurfactant production to elucidate potential bottlenecks. This research aims to assess the techno-economic and environmental performance of surfactin production in a potential scale of 65m3, considering different product yields and involving the European energy crisis of 2021-2022. The conceptual design, simulation, techno-economic, and environmental assessments were done by applying process engineering concepts and software tools such as Aspen Plus v.9.0 and SimaPro v.8.3.3. The results demonstrated the high economic potential of surfactin production since the higher values in the market offset the low fermentation yields, low recovery efficiency, and high capital investment. The sensitivity analysis of the economic assessment elucidated a minimum surfactin selling price between 29 and 31 USD/kg of surfactin, while a minimum processing scale for economic feasibility between 4 and 5 kg/h is needed to reach an equilibrium point. The environmental performance must be improved since the carbon footprint was 43 kg CO2eq/kg of surfactin. The downstream processing and energy demand are the main bottlenecks since these aspects contribute to 63 and 25% of the total emissions. The fermentation process and downstream process are key factors for future optimization and research.

8.
Artículo en Inglés | MEDLINE | ID: mdl-38696007

RESUMEN

Lignocellulosic biomass is widely available in the world. However, a consensus has yet to be established to evaluate the biomass valorization alternatives. The chemical composition is the primary technical limitation in selecting a transformation route to obtain value-added products. In this paper, the bagasse from non-centrifuged sugar (NCS) production and Pinus patula (PP) wood chips were analyzed in terms of complete chemical composition to establish their potential for selecting the transformation routes. A strategy to select the best route based on the chemical composition was applied and a feedstock criteria model was proposed. Schemes were obtained and compared using a bioprocess selection strategy proposed in previous works. As a result, the preliminary biorefinery schemes were finally defined. The assessment of schemes derived from the outlined strategy included technical, economic, environmental, and social analyses. The environmental evaluation was complemented with a geolocation assessment, revealing a 0.75-ton CO2-eq/yr contribution to the carbon footprint for local distribution. The sustainability index for the PP biorefinery and the bagasse from NCS production was analyzed, resulting in indices of 44.8 and 60.9, respectively. These values were primarily derived from the economic and environmental analyses of both processes.

9.
Rev Biol Trop ; 61(2): 859-73, 2013 Jun.
Artículo en Español | MEDLINE | ID: mdl-23885596

RESUMEN

Hyphessobrycon with 129 valid species, is a genus of fish that has a great diversity of species in the Neotropical ichthyofauna, reaches its greatest diversity in the Amazon basin with about 70% of these species, is highly desired by hobbyists because of their beauty and color, and are still meeting new species. We analyzed specimens from the Departamento de Ictiología, Museo de Historia Natural de la Universidad Mayor de San Marcos, Lima, Perú (MUSM); and measurements of the specimens were taken point to point with digital calipers. Observations of bone and cartilage structures were made on cleared and stained (C&S) samples. The morphometric relationships between species using 21 variables were explored using a principal component analysis (PCA). Here we describe two new species, Hyphessobrycon taphorni and H. eschwartzae from the Madre de Dios River drainage, Peru. Hyphessobrycon taphorni sp. n. can be distinguished by the number of dorsal-fin rays (iii, 8), by the number of: pored lateral-line scales (4-5), teeth in the outer premaxillary row (1-2), teeth in the inner premaxillary row (7-8), by: the caudal-peduncle length (11.4-16.4% SL), number of lateral scales (28-29, except from H. loretoensis which has 29-30) and absence of a humeral spot (vs. present), it differs from H. loretoensis by the number of: scales between the lateral line and the anal fin origin (4 vs. 3) and maxillary teeth (2 vs. 3-4), and it differs from H. agulha by the number of branched pectoral-fin rays (11-12 vs. 9-10). Hyphessobrycon eschwartzae sp. n. is distinguished by the number of: simple anal-fin rays (iv), teeth on the dentary (13-15), teeth in the inner premaxillary row (6), teeth in the outer premaxillary row (3, except from H. heterorhabdus and H. loretoensis which have 3-4); it differs from H. loretoensis by the number of: pored lateral-line scales (7 vs. 9-10), scales between the lateral line and the dorsal-fin origin (5 vs. 3-4); it differs from H. agulha in the number of lateral scales (30-31 vs. 33-34), by the number of: predorsal scales (9 vs. 10), maxillary teeth (4 vs. 0-1); in having in life a red lateral stripe above the dark lateral stripe that extends from the posterior part of the opercle to the caudal peduncle (vs. absent) and by the presence of bony hooks in mature males only on the anal fin (vs. hooks on all fins, including the caudal).


Asunto(s)
Characidae/anatomía & histología , Characidae/clasificación , Animales , Femenino , Masculino , Perú , Ríos
10.
Rev Biol Trop ; 61(1): 181-92, 2013 Mar.
Artículo en Español | MEDLINE | ID: mdl-23894972

RESUMEN

The genus Hyphessobrycon is included within the subfamily Tetragonopterinae. The species are generally small, do not exceed 70mm of standard length, are economically important as ornamental fish, with 128 valid species distributed from Southern Mexico to Rio La Plata in Argentina. The collections of fish were made with seines, in a single biotope, along shore in backwaters and working downstream. Measurements of the specimens were taken point to point with digital calipers. Observations of bone and cartilage structures were made on cleared and stained (C&S) specimens. The morphometric relationships between species were explored using a principal component analysis (PCA)using 21 variables. We described a new species, Hyphessobrycon chocoensis, from the Telembi River drainage of the Pacific versant of Colombia. The new species, Hyphessobrycon chocoensis, is distinguished from congeners not of the "flammeus" species group by: having a diffuse humeral spot, in lacking a dark spot on the dorsal fin and caudal peduncle. It is distinguished from members its species group by the number of rays in the dorsal fin (ii, 8, i), by the number of branched anal-fin rays (25-26) and by having a diffuse humeral spot. It differs from H. tortuguerae in the number of teeth on the maxilla (1-2), by the number of predorsal scales and the high number of scales between the lateral line and the anal fin (6-7). Hyphessobrycon chocoensis can be distinguished from the other known species of Hyphessobrycon from the Pacific Coast of Colombia in having: a high number of pored lateral-line scales, by the snout to dorsal-fin length, by caudal-peduncle depth and by eye diameter. In addition, it differs from H. columbianus by the distance from the dorsal fin to the anal fin, by the length of the upper jaw, and by snout length. It differs from H. condotensis in having a high number of scales between the lateral line and the dorsal fin, and by the number of simple rays in the anal fin. H. chocoensis is distinguished from H. sebastiani by the number of transverse scales and the number of scales between the lateral line and the dorsal fin. A taxonomic key is provided to aid with the identification of the species of Hyphessobrycon from the Pacific Coast of Colombia.


Asunto(s)
Characidae/anatomía & histología , Characidae/clasificación , Animales , Colombia , Masculino , Ríos
11.
Rev Biol Trop ; 61(3): 1365-87, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24027929

RESUMEN

Fish biodiversity of aquatic ecosystems is highly threatened by different economic activities driven by human populations, and its description is increasingly a priority. For the Cauca-Magdalena River system we have described 14 species, and the purpose of this paper was to describe three new species belonging to the same genus Hemibrycon from the Nare and Guatapé River drainages of the middle Magdalena River, Colombia. The description was based on a series of 200 specimens, and the use of morphometric, meristic and osteological characters, as well as fish distribution and morphogeometric analytical methods. We have found that Hemibrycon fasciatus n. sp. (n = 54) differs from other species of Hemibrycon (that also have a vertical humeral spot) in having: melanophores outlining the posterior margins of the scales along sides of body; humeral spot extending onto posterior margin of opercle; a dark lateral stripe, formed by deep pigment that is continuous with the peduncular spot; the toothed portion of the maxilla not reaching the dorsal margin of the dentary (vs. toothed portion of maxilla extending beyond dorsal margin of dentary); all maxillary teeth tricuspid (vs. some unicuspid teeth present on maxilla). H. cardalensis n. sp. (n = 64) differs in having: a vertically elongate humeral spot that extends one or two scales below the lateral line canal. H. cardalensis n. sp. differs from all congeners in having the pigment of the caudal spot restricted to the ventral half of the caudal peduncle, and in having melanophores around the anterior scales of the lateral line. Hemibrycon antioquiae n. sp. (n = 82) differs in having a circular humeral spot. It differs from the other species with a circular humeral spot, like H. mikrostiktos, in having a projection of disperse melanophores extending from the dorsal margin of the humeral spot to below the lateral stripe. Habitat data and environmental impacts caused by the construction of reservoirs for hydroelectric projects and other threats in the area are included, as well as a key to all species Hemibrycon present in the Magdalena River Basin. The synonymy of H. pautensis with H. polyodon is discussed and H. pautensis is revalidated.


Asunto(s)
Biodiversidad , Characidae/anatomía & histología , Characidae/clasificación , Animales , Colombia , Ríos
12.
Environ Sci Pollut Res Int ; 30(4): 8790-8808, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35655013

RESUMEN

The objective of this study is to compare the environmental and social performance of two small-scale avocado biorefineries implanted in a rural zone in the North of Colombia. Two small-scale biorefineries were proposed. Small-B1 addressed to produce avocado oil and animal feed, and Small-B2 focused on the guacamole production. The environmental analysis was done by applying the life cycle assessment methodology. Then, agronomic information and process simulation were required to complete the analysis. Moreover, the water footprint of the avocado crops was estimated. Both biorefineries were compared with the direct avocados production and commercialization. The social assessment was achieved by the estimation of quantitative indicators related to wages, jobs, and working hours. The agricultural carbon and water footprints of the creole avocado crop were 0.59 kg CO2-eq/kg and 2.13 m3/kg. In the same way, Small-B1 and Small-B2 obtained a carbon and water footprints of 8.99 kg CO2-eq/kg and 6.63 m3/kg and 0.72 kg CO2-eq/kg and 1.38 m3/kg, respectively. The hotspots of the creole avocado crop are related to the use of fertilizers and fungicides. Then, new strategies should be implemented to reduce the farmer's dependency. The social analysis exhibit a high resilience of the Small-B1 biorefinery since a salary increase to worker about 50% can be proposed. In addition, the installation of this biorefinery can create more than ten jobs. A disjunction was found between the economic, environmental, and social analyses. Thus, the need to establish a multidimensional strategy to design sustainable biorefineries is presented.


Asunto(s)
Persea , Animales , Colombia , Dióxido de Carbono , Cambio Social , Agua , Estadios del Ciclo de Vida
13.
Foods ; 12(11)2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37297474

RESUMEN

Many plant species characterize tropical forests, and a small fraction has been studied to favor small communities in the food and medicinal fields. The high biodiversity of these regions allows for the proposed alternatives for the valorization of exotic fruits due to their rich content of value-added compounds that benefit human health. This work focuses on improving the nutritional characteristics of the açai production chain by mixing it with noni and araza. As a main result, it was possible to enhance the organoleptic and nutritional characteristics of the fruits after freeze-drying. Then, the seeds and peels of the fruits were valorized by the extraction of bioactive compounds with conventional methods and biogas production by anaerobic digestion. The best compositions of antioxidant capacity and total phenolic compounds were obtained for the extracts based on the araza peel, with values of 116.4 µmol and 276.6 mg of gallic acid per 100 g of raw material, respectively. Regarding biogas production, the anaerobic digestion performance was influenced by the C/N ratio. The experimental results were used as input to simulate small-scale processes. From a technical point of view, the scheme of açai, noni, and araza mixture (Sc. 4) showed the highest mass yields (0.84 kg products/kg RM) and energy requirement (2.54 kW/kg RM). On the other hand, the processing of single açai (Sc. 1) presented the lowest capital costs (1.37 M-USD) and operating costs (0.89 M-USD/year). However, all scenarios showed techno-economic feasibility and demonstrated the potential of these fruits to valorize the açai market.

14.
Materials (Basel) ; 16(15)2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37570205

RESUMEN

Lignocellulosic materials are usually processed toward C5 and C6 corresponding sugars. Trifluoroacetic acid (TFA) is a pretreatment method to solubilize hemicellulose to sugars such xylose without degrading cellulose. However, this pretreatment has not been compared to other processes. Thus, this paper focuses on the techno-economic comparison of the C5-C6 production of C5-C6 as raw materials platforms using non-centrifuged sugarcane bagasse (NCSB) and Pinus patula wood chips (PP). Hydrolysates using TFA 2.5 M as an acid were characterized through HPLC regarding arabinose, galactose glucose, xylose, and mannose sugars. Then, simulations of the processes according to the experimental results were done. The economic assessment was performed, and compared with some common pretreatments. The mass and energy balances of the simulations indicate that the process can be compared with other pretreatments. From the economic perspective, the main operating expenditures (OpEx) are related to raw materials and capital depreciation due to the cost of TFA corrosion issues. The processes showed a CapEx and OpEx of 0.99 MUSD and 6.59 M-USD/year for NCSB, and 0.97 MUSD and 4.37 MUSD/year for PP, considering a small-scale base (1 ton/h). TFA pretreatment is innovative and promising from a techno-economic perspective.

15.
PLoS One ; 18(1): e0279924, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36662755

RESUMEN

Hyphessobrycon is one of the most species rich and widely distributed genera in the family Characidae, with more than 160 species ranging from Veracruz, Mexico to Mar Chiquita Lagoon in Buenos Aires, Argentina. The majority of Hyphessobrycon diversity shows a cis-Andean distribution; only nine species are trans-Andean including H. compressus (Meek 1908). It is well established that Hyphessobrycon is not monophyletic but it has been suggested that natural groups can be identified within the larger Hyphessobrycon species group. In this study, we tested the monophyly of trans-Andean species of Hyphessobrycon and investigated the placement of H. compressus. We inferred the first phylogenomic hypothesis of trans-Andean Hyphessobrycon that includes nearly complete taxonomic sampling (eight of nine valid species) using ultraconserved elements (UCEs). We analyzed 75% (1682 UCEs), 90% (1258 UCEs), and 95% (838 UCEs) complete data matrices, and inferred phylogenomic hypotheses under concatenation and coalescent approaches. In all cases, we recovered the monophyly of trans-Andean Hyphessobrycon inclusive of H. compressus, strong support for three species groups, and evidence of cryptic diversity within the widespread H. compressus and H. condotensis. We used our phylogenomic hypothesis to investigate the biogeographic history of Hyphessobrycon in Middle America. Our ancestral range estimation analysis suggests a single event of cis- to trans-Andean colonization followed by stepwise colonization from the Pacific slope of northwestern South America (Chocó block) to northern Middle America (Maya block). Our work supports the recognition of the trans-Andean species as Hyphessobrycon sensu stricto and provides an evolutionary template to examine morphological characters that will allow us to better understand the diversity of Hyphessobrycon in Middle America.


Asunto(s)
Characidae , Animales , Filogenia , América del Sur , Colombia , América del Norte
16.
Infect Prev Pract ; 5(4): 100302, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37840847

RESUMEN

Background: The COVID-19 pandemic generated high workloads given the high volume of seriously ill patients; conditions that could increase the risk of adverse events (AE). This study analyzed the frequency of AE in patients with COVID-19 and their effect on mortality, hospital stay and costs. Methods: This retrospective cohort study included in-patients with COVID-19 at a single hospital between March 2020-June 2021. Exposure was the occurrence of at least one AE. Hospital stay, costs and death were considered outcomes. Clinical information and direct costs were obtained from medical and billing records. Generalized linear models were used to estimate the association measures. Results: 405 patients were included, 55.8% (n=226) men, median age 56 years (IQR: 41.0-70.0) and with a history of hypertension (26.2%; n=106), diabetes mellitus (13.8%; n=56) and obesity (13.8%; n=56). The incidence of AE was 13.3% (n=54), 29 patients presented more than one AE, for a total of 70 events. Most events (74.3%; n=52) were preventable and the most frequent were healthcare-associated infections (50%; n=35), phlebitis (14.3%; n=10) and pressure ulcers (12.9%; n=9). AE prolonged hospital stay (change rate: 1.57; 95%CI: 1.26-1.95; P=0.001) and increased direct healthcare costs (change rate: 1.20; 95% CI: 1.03-1.39, P=0.019). Likewise, the risk of death was 56% higher in patients with AE. Conclusion: Pandemics are unexpected events that present challenges to safe healthcare. Improving quality policies, monitoring compliance with protocols and providing ongoing education are strategies to prevent AE such as healthcare-associated infections, which increase hospital costs and stay.

17.
Rev Biol Trop ; 60(4): 1873-88, 2012 Dec.
Artículo en Español | MEDLINE | ID: mdl-23342535

RESUMEN

Neotropical fish live in streams with considerable spatial and temporal variability of their food items. Food availability depends on different factors such as discharge, channel morphology, physicochemical conditions and interactions with other species, as well as their food habits. On the other side, good food availability results in reproductive success. Because the study of those changes contributes to a better understanding of trophic interactions in fish populations, the present work describes and evaluates aspects of diet and reproduction of Farlowella vittata in Pringamosal Creek, Güejar River drainage, Orinoco River basin, Colombia. Five collecting expeditions were done during both high and low rain seasons of 2008 and 2009. Physical and chemical water parameters were measured, and fish were captured from several points along the total length of the 7km stream, to characterize their biometry and stomach contents. Our results showed that Pringamosal creek is a first order stream, about 3.5m wide and with an average depth of 1m in our study area. Dissolved oxygen values were 6.2mg/L during low water and 2.7mg/L during high water phase. The creek is classified as oligotrophic but with a tendency to eutrophication. A total of 130 fish samples were analyzed. Fishes were assigned to seven size range categories between 86.0 and 175.5mm standard length (SL). Stomach contents revealed that the diet of this species consisted mainly of algae (Bacillariophyceae) (84.6% Abundance Relative), but we observed a variation in the diet according to season; during low rainfall it feeds on phytoplankton (86.47% A.R.) and during high rainfall on zooplankton as well as plant material and organic material (0.685% A.R. and 18.83% A.R., respectively). A Kruskal-Wallis ANOVA showed statistically significant differences in food items between sexes. The condition factor (K) indicated that the species was well fed. Size at sexual maturity was 154mm SL for males and 124mm SL for females. The gonadosomatic index (RGS) showed that this fish reproduced during high water (April-May) season, and females showed a fecundity of 1 819 ovocites, with an average diameter of 1.4mm. Although parental care was not observed during this study, it is well known that males protect their eggs and juveniles, making them easy to capture during the breeding periods identified in this study, and at the same time, vulnerable to overexploitation. We recommend an urgent management plan for the conservation of this species, since at this time, no fishing controls are enforced even though it is harvested as an ornamental species.


Asunto(s)
Bagres/fisiología , Preferencias Alimentarias/fisiología , Contenido Digestivo , Reproducción , Animales , Bagres/anatomía & histología , Bagres/clasificación , Colombia , Femenino , Masculino , Ríos , Estaciones del Año
18.
Bioresour Technol ; 350: 126852, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35183725

RESUMEN

Process sustainability has been one of the most challenging issues faced by process designers. Conceptual designed processes do not overcome this stage because aspects such as context and technological readiness level are left aside. This paper proposes a strategy to consider different processing routes for biomass (compendium of existing routes) towards sustainable development. The strategy comprises five stages where a supported bioprocesses selection is made by considering the chemical composition of the raw material and the context where biomass is produced and processed. This strategy aims to give decision tools to designers to filter and reduce the number of options to be considered when proposing an alternative biomass use. The proposed strategy was applied to upgrade orange peel waste and sugarcane bagasse to demonstrate how it can be applied. In conclusion, selecting of bioprocesses and considering the proposed strategycould improve the biorefineries design. Even so, more bioprocesses must be included.


Asunto(s)
Celulosa , Saccharum , Biomasa , Desarrollo Sostenible
19.
Rev Biol Trop ; 59(2): 709-25, 2011 Jun.
Artículo en Español | MEDLINE | ID: mdl-21721235

RESUMEN

Hyphessobrycon is the most numerous and morphologically complex genus of Characidae, and includes 18 species reported for Colombia, from which thirteen belong to the heterorhabdus-group different methods have been proposed for species identification within this genus. This study used these species to undertake a morphogeometric analysis by the Box Truss and Thin Plate Splin (TPS) methods; 13 homologous landmarks type I and three type II were used. The result of cluster analysis indicated that these species are represented by two big groups: robust and thin. The uniform and non uniform components, and the principal warps (WP) and partial warps (Wparc), described the shape changes related to body depth, involving relative displacements of the appendicular skeleton and the cephalic region. All species were characterized by allometric growth with the exception of Hyphessobrycon mavro, who presented an isometry between the landmarks 6-7. Two new measures are proposed for species discrimination in the group (snout-supraoccipital spine distance and supraoccipital spine-pelvic fin).


Asunto(s)
Peces/anatomía & histología , Peces/clasificación , Animales , Análisis por Conglomerados , Colombia , Análisis de Componente Principal , Especificidad de la Especie
20.
Bioresour Technol ; 340: 125626, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34325388

RESUMEN

Sustainable development goals (SDGs) are guidelines to improve the socio-economic and environmental worldwide situation caused by excessive fossil fuel use. These goals must be accomplished before 2030 by implementing a national sustainable development framework in all UN country members. Instead, biorefineries are the seed towards a more sustainable world since biomass upgrading into a series of value-added products and energy vectors can reduce current issues related to waste generation and climate change. Besides, biorefineries are the first step on the way to implement a bioeconomy. This review paper aims to elucidate the existing relation between biorefineries, bioeconomy, and the SDGs through a comprehensive analysis of the technical requirements, challenges, and perspectives of biomass upgrading processes. In this way, this review paper includes a discussion about the biorefinery, bioeconomy, sustainable development, and sustainability concepts. Moreover, this paper elucidates how the implementation of biorefineries is linked to the SDGs accomplishment.


Asunto(s)
Objetivos , Desarrollo Sostenible , Biomasa , Combustibles Fósiles
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