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Id: biblio-1283600
Autor: Oestreich, Arne Michael; Ilire Suli, Merlinda; Gerlach, Doreen; Fan, Rong; Czermak, Peter.
Título: Media development and process parameter optimization using statistical experimental designs for the production of nonribosomal peptides in Escherichia coli
Fonte: Electron. j. biotechnol;52:85-92, July. 2021. graf, tab.
Idioma: en.
Resumo: BACKGROUND: Nonribosomal peptide synthases (NRPS) can synthesize functionally diverse bioactive peptides by incorporating nonproteinogenic amino acids, offering a rich source of new drug leads. The bacterium Escherichia coli is a well-characterized production host and a promising candidate for the synthesis of nonribosomal peptides, but only limited bioprocess engineering has been reported for such molecules. We therefore developed a medium and optimized process parameters using the design of experiments (DoE) approach. RESULTS: We found that glycerol is not suitable as a carbon source for rhabdopeptide production, at least for the NRPS used for this study. Alternative carbon sources from the tricarboxylic acid cycle achieved much higher yields. DoE was used to optimize the pH and temperature in a stirred-tank reactor, revealing that optimal growth and optimal production required substantially different conditions. CONCLUSIONS: We developed a chemically defined adapted M9 medium matching the performance of complex medium (lysogeny broth) in terms of product concentration. The maximum yield in the reactor under optimized conditions was 126 mg L-1, representing a 31-fold increase compared to the first shaking-flask experiments with M9 medium and glycerol as the carbon source. Conditions that promoted cell growth tended to inhibit NRPS productivity. The challenge was therefore to find a compromise between these factors as the basis for further process development.
Descritores: Peptídeo Sintases/metabolismo
Reatores Biológicos/microbiologia
Escherichia coli
-Temperatura
Biotecnologia
Carbono/metabolismo
Modelos Estatísticos
Eletroforese em Gel de Poliacrilamida
Bioengenharia
Concentração de Íons de Hidrogênio
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1253018
Autor: Woo Kim, Kyung; Choi, Tae-Young; Min Kwon, Yong; Hwan Kim, Jaoon Young.
Título: Simple synthesis of photoluminescent carbon dots from a marine polysaccharide found in shark cartilage
Fonte: Electron. j. biotechnol;47:36-42, sept. 2020. tab, ilus, graf.
Idioma: es.
Projeto: National Marine Biodiversity Institute of Korea (MABIK).
Resumo: BACKGROUND: For more than a decade, water-soluble, eco-friendly, biocompatible, and low-toxicity fluorescent nanomaterials have received considerable attention for their numerous in vivo and in vitro applications in biomedical imaging, disease diagnostics, and environmental monitoring. Owing to their tunable photoluminescence properties, carbon-based luminescent nanomaterials have shown great potential in bioimaging, photocatalysis, and biosensing among other applications. RESULTS: Marine environments provide excellent resources for the fabrication of these nanomaterials, because many marine organisms contain interesting trigger organic compounds that can be used as precursors. Herein, we synthesize multi-color emissive carbon dots (CDs) with an intrinsic photoluminescence quantum yield of 20.46%. These nanostructures were achieved through the one-step hydrothermal treatment of marine polysaccharide chondroitin sulfate, obtained from shark cartilage, in aqueous solution. CONCLUSIONS: We successfully demonstrate the low toxicity of our marine resource-derived CDs in zebrafish, and provide an initial assessment of their possible use as a bioimaging agent. Notably, the newly synthesized CDs localize in the intestines of zebrafish larvae, thereby indicating their biocompatibility and potential use as in vivo dyes.
Descritores: Polissacarídeos/química
Tubarões
Carbono/química
Pontos Quânticos/química
-Peixe-Zebra
Carbono/toxicidade
Cartilagem
Pontos Quânticos/toxicidade
Luminescência
Nanoestruturas
Corantes/toxicidade
Corantes/química
Limites: Animais
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-830547 LILACS-Express
Autor: Quiceno Urbina, Nubia Janeth; Tangarife Marín, Gloria Mónica; Álvarez León, Ricardo.
Título: Estimación del contenido de biomasa, fijación de carbono y servicios ambientales, en un área de bosque primario en el resguardo indígena piapoco chigüiro-chátare de barrancominas, departamento del guainía (colombia) / Estimated biomass content, carbon sequestration and environmental services,in a forest area in the shelter primary indian piapoco chigüiro-chátare, barrancominas, guainia department (colombia)
Fonte: Rev. luna azul;(43):171-202, jul.-dic. 2016. ilus, tab.
Idioma: es.
Resumo: En Barrancominas (Guainía, Colombia) las diferentes formas culturales de trabajo y producción de la comunidad Piapoco, incluyen la tumba y quema de bosques a orillas del río, para ampliación de frontera agrícola, establecimiento de cultivos ilícitos y potreros; lo cual contribuye en el aumento de las concentraciones de carbono en la atmósfera que, a la vez, repercute en el cambio climático global. En consecuencia, el presente estudio quiso estimar el contenido de biomasa, fijación de carbono y los servicios ambientales, en un área de bosque primario en el Resguardo Indígena Chigüiro-Chátare, empleando una metodología no destructiva. Se estimó tanto la biomasa aérea, como el contenido de carbono (C) del estrato arbóreo del bosque por hectárea y la tasa de producción de hojarasca de las especies maderables: Mure, Pendare y Arenillo blanco. La biomasa aérea fue estimada a partir de los parámetros medidos en campo como altura y DAP y densidades de la madera de cada especie. Además, se analizó la dominancia de las especies para de esta forma conocer la representatividad del aporte de biomasa aérea y contenido de carbono en el bosque.

In Barrancominas (Guainía) different cultural forms of work and production of the Piapoco community, includes the slash and burn of forest along the river, to extend the farming, establishment of illicit crops and pastures contribute to increase carbon concentrations in the atmosphere which in turn affect global climate change. Thus this study wanted to value the biomass content, carbon fixation and ecosystem services in an area of primary forest in the indigenous community of Chigüiro-Chátare using a nondestructive method or indirect. In this study the aerial biomass was estimated as well as the carbon (C) content of the arboreal stratum of forest per hectare and production rate of dead leaves of three species forestry Mure, Pendare and Arenillo trees. The aerial biomass was estimated from the measured parameters in field such as: height, DAP and wood densities of each species. In addition, the species dominance was analyzed in order to know the representativeness of the biomass contribution and carbon content in the forest.
Descritores: Biomassa
-Carbono
Florestas
Agricultura Florestal
Limites: Humanos
Tipo de Publ: Artigo Clássico
Responsável: CO54.1 - Centro de Biblioteca e Información Científica


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Id: biblio-902042 LILACS-Express
Autor: Macías Socha, Claudia; García Colmenares, Mauricio; Chaparro S. , Patricia.
Título: Determinación electroquímica de plomo y cadmio en aguas superficiales / Electrochemical determination of lead and cadmium in surface water
Fonte: Rev. luna azul;(44):27-38, ene.-jun. 2017. ilus, tab.
Idioma: es.
Resumo: El método voltametría de onda cuadrada (OSWV) fue validado para la cuantificación de Cd2+ y Pb2+ en aguas superficiales. El estudio fue realizado usando solución Britton-Robinson como electrolito de soporte a pH 4,8, carbón vítreo como electrodo de trabajo, Ag/AgCl como electrodo de referencia y platino como electrodo auxiliar. La técnica presenta un límite de detección 211 ug/L para Pb y 268 ug/L para Cd. La aplicación de la técnica voltamétrica OSWV fue realizada en aguas de la quebrada Las Torres del sector Parque Industrial en Sogamoso (Colombia), hallando una concentración de: Pb2+ 0,750±0,067 mg/L y Cd2+ 0,570±0,071 mg/L, los cuales sobrepasan los límites máximos establecidos por las normas nacionales (Decreto 4728/2010) e internacionales vigentes para aguas residuales. Los resultados fueron contrastados por el método de referencia espectrofotometría de absorción atómica aceptado como referencia, permitiendo deducir que el método electroquímico genera resultados con un nivel de confianza del 95%.

The square wave electrochemical voltammetry method (OSWV) to quantification of cadmium and lead in surface waters was validated. It used a Britton-Robinson buffer as solution supporting electrolyte to pH 4.8, working electrode glassy carbon, Ag/AgCl as reference electrode and platinum as counter electrode. The limit of detection determined was 211 ug/L for Pb and 268 ug/L for Cd. The application of voltammetric technique OSWV was performed in waters of the creek Towers Industrial Park Sector in Sogamoso (Colombia). The ions concentration in the samples analyzed was 0.750±0.067 mg/L for Pb2+ and 0.570±0.071 mg/L for Cd2+, exceeding the national and international standards limits for wastewater. The results obtained by voltammetry were compared with atomic absorption method spectrophotometer traditionally accepted, allowing deducing that the voltammetric method generates results with a confidence level of 95%.
Descritores: Metais Pesados
-Carbono
Eletroquímica
Chumbo
Limites: Humanos
Tipo de Publ: Artigo Clássico
Responsável: CO54.1 - Centro de Biblioteca e Información Científica


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Id: biblio-1008400
Autor: Zuluaga Zuluaga, Liliana(com); Castro Escobar, Edisson Stiven(com).
Título: VALORACIÓN DE SERVICIOS AMBIENTALES POR CAPTURA DE CO2 EN UN ECOSISTEMA DE BOSQUE SECO TROPICAL EN EL MUNICIPIO DE EL CARMEN DE BOLÍVAR, COLOMBIA / ASSESSMENT OF ENVIRONMENTAL SERVICES BY CO2 CAPTURE IN A TROPICAL DRY FOREST ECOSYSTEM IN THE MUNICIPALITY OF EL CARMEN DE BOLIVAR, COLOMBIA
Fonte: Rev. luna azul;47:1-20, 01 julio 2018. ilus, tab, graf.
Idioma: en; es.
Resumo: Este trabajo de investigación analiza la estructura del ecosistema de bosque seco tropical en siete segmentos estudiados en el municipio de El Carmen de Bolívar, Colombia. Se tiene como objetivo estimar la captura de carbono en el compartimiento fustal, para luego calcular el valor monetario de los servicios ambientales de almacenamiento de CO2. La valoración se realizó utilizando una base de datos construida a partir de un muestreo de árboles por transectos; esto permitió establecer los tipos de especies, densidad, altura comercial y el diámetro a la altura del pecho de la madera. Finalmente se calculó mediante estas variables, el stock de biomasa aérea a través de tres modelos de estimación alométrica. En los resultados se evidencian impactos de origen antropogénico en el bosque, aunque aún hay un número importante de especies nativas; sin embargo estas son principalmente caducifolias, lo que reduce el stock de captura de CO2 debido a los ciclos de defoliación natural. A pesar de esto el ecosistema es un sumidero importante de carbono.

This research analyzes the structure of the tropical dry forest ecosystem in seven segments studied in the Municipality of El Carmen de Bolívar, Colombia. The objective was to estimate the carbon capture in the fustal compartment and then calculate the monetary value of the environmental services of CO2 storage. The assessment was carried out using a database designed from the sampling of trees by transects. This allowed establishing types of species, density, commercial height and diameter at breast height of the wood. Finally, the stock of air biomass was calculated by means of these variables through three models of allometric estimation. The results show an impact of anthropogenic origin in the forest although there is still a dignificant number of native species. However, these are maninly caducifolias which reduce the stock of CO2 capture due to natural defoliation cycles. Despite of this, the ecosystem is an important carbon sink.
Descritores: Florestas
-Carbono
Dióxido de Carbono
Ecossistema
Limites: Humanos
Tipo de Publ: Artigo Clássico
Responsável: CO54.1 - Centro de Biblioteca e Información Científica


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Id: biblio-1142508
Autor: Barth, Gabriel; Gotz, Lenir Fátima; Favaretto, Nerilde; Pauletti, Volnei.
Título: Does Dairy Liquid Manure Complementary to Mineral Fertilization Increase Grain Yield Due to Changes in Soil Fertility?
Fonte: Braz. arch. biol. technol;63(spe):e20190537, 2020. tab, graf.
Idioma: en.
Resumo: Abstract The main destination of manure is the application to croplands near livestock farms as nutrient source to enhance crop production. The aim of this study was to define the dairy liquid manure (DLM) dose, complementary to the mineral fertilizer, for higher crops yield, in rotation black oat-maize-wheat-soybean, and to identify the soil chemical variables improved by the manure that most affect the yield, in long-term. The experiment was conducted from 2006 to 2015, in no-tillage system, at Paraná State, Brazil. The soil was a Latossolo Bruno Distrófico típico, clayey texture. The treatments consisted by doses of DLM (0, 60, 120 and 180 m3 ha-1 year-1), complementary to the mineral fertilizer (applied in the same amount for all DLM doses). Crops yield and soil chemical variables were evaluated at six depths (0-10; 10-20; 20-30; 30-40; 40-50 and 50-60 cm). The DLM application increased the yield of all crops, but not in all harvests. The DLM even applied at soil surface improved the soil chemical variables in deep layers, resulting in high positive correlation between yield and exchange bases, P, Zn and Mn contents, and high negative correlation with Ca/Mg ratio and potential acidity at depth 0-10 cm. The DLM dose, complementary to the mineral fertilization, that provided higher soybean and wheat yield was about 130 m3 ha-1 year-1, while for maize this dose was equal to or greater than 180 m3 ha-1 year-1. This effect was not attributed to a single chemical variable but the improvement of all chemical variables evaluated.
Descritores: Solo/química
Fertilizantes
Produção Agrícola/métodos
Esterco
-Fósforo/análise
Soja
Triticum
Carbono/análise
Avena
Produtos Agrícolas
Zea mays
Fazendas
Minerais/análise
Nitrogênio/análise
Limites: Humanos
Animais
Responsável: BR1.1 - BIREME


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Id: biblio-1142511
Autor: Canalli, Lutécia Beatriz dos Santos; Santos, Josiane Bürkner dos; Benassi, Dácio Antônio; Francisco, André Luiz Oliveira de; Benassi, Caetano; Aguiar, Adriane Novakowski de; Cordeiro, Elielson; Mendes, Renan Stanislavski.
Título: Soil Carbon and Structural Quality in Crop Rotations under No-tillage System
Fonte: Braz. arch. biol. technol;63(spe):e20190603, 2020. tab, graf.
Idioma: en.
Resumo: Abstract The no-tillage system associated with crops rotation affects the dynamics of soil organic matter, influencing the formation, reorganization and stabilization of aggregates and the carbon content (C) into soil aggregates. The aim of this study was to evaluate the effect of crop rotations under no-tillage system on C content and soil aggregation. The experiment was conducted at the Paraná Agronomic Institute in Ponta Grossa, PR, Brazil. The treatments consisted of six crop rotations, in a 3-year cycle, arranged in a randomized block design with four replications. Soil samples were collected at layers of 0-5, 5-10 and 10-20 cm. The aggregate classification was determined by the wet sieving methodology, and the Weighted Mean Diameter (WMD), Geometric Mean Diameter (GMD) and Aggregate Stability Index (ASI) were calculated. The C content in the aggregates was determined by wet oxidation. The results were submitted to analysis of variance and Tukey test at 5% probability. There was no difference among crop rotations for aggregate classes and aggregation indexes, but were higher in surface, decreasing in depth. The carbon content in the aggregates did not differ among crop rotations, but presented stratification in the soil profile, decreasing in depth. The cycle of three years with crop rotation was insufficient to express possible changes in soil C content and aggregation.
Descritores: Solo/química
Carbono/química
Rotação de Cultivos
Fertilizantes
-Brasil
Produtos Agrícolas
Modelos Teóricos
Limites: Humanos
Responsável: BR1.1 - BIREME


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Id: biblio-1142512
Autor: Rosa, Graciele Ferreira da; Casali, Carlos Alberto; Bechara, Fernando Campanha; Viceli, Jéssica Maiara; Moreira, Flavia Lima; Guimarães, Bruna Schneider; Ferreira, André Francisco; Peppe, Isabella Araújo; Acosta, Amanda Cristina Beal; Dôres, Letícia de Alcântara; Feix, Bruna Larissa.
Título: Soil Microbiological Attributes Under Ecological Restoration Technologies in Subtropical Forest
Fonte: Braz. arch. biol. technol;63(spe):e20190651, 2020. tab.
Idioma: en.
Resumo: Abstract To accelerate the recovery of degraded environments, it is necessary to use ecological restoration techniques, which require validation according to the ecosystem conditions where are implemented. This work aimed to evaluate soil microbiological attributes under different ecological restoration technologies in a subtropical forest. The study was conducted at UTFPR-DV, southwest of Paraná, in an ecotone between Mixed Ombrophilous Forest and Semideciduous Seasonal Forest and on an Oxisol. In December 2010, a tillage area of at least 17 years old was isolated and the passive restoration, tree planting and nucleation treatments were installed in 40x54 m plots and four replications. In November 2018 the soil was sampled in these plots and in a native forest area as a reference. There were calculated soil organic carbon content (OCC) and microbiological attributes such as microbial biomass N and C (NMIC and CMIC), basal respiration, fungal spore content and the metabolic (qCO2) and microbial quotient (MICq). It can be concluded that nucleation technology can restore soil microbiological attributes but has not yet reached the conditions of a natural environment. Passive restoration is not a good technology for restoring soil microbiological attributes. The higher contents of CMIC, NMIC, OCC, MICq and fungal spores in the soil under native forest compared to ecological restoration technologies indicate that eight years of adoption of these techniques have not yet been enough to fully recover soil microbiological activity.
Descritores: Microbiologia do Solo
Florestas
Conservação dos Recursos Naturais/métodos
-Esporos Fúngicos
Clima Tropical
Brasil
Carbazóis
Carbono/análise
Nitrogênio/análise
Responsável: BR1.1 - BIREME


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Id: biblio-1142513
Autor: Guera, Keli Cristina Silva; Fonseca, Adriel Ferreira da; Ribeiro, Fernanda.
Título: Stocks and Distribution of Soil Carbon, Nitrogen, Phosphorus and Sulfur in an Integrated Crop-Livestock System Treated with Phosphates
Fonte: Braz. arch. biol. technol;63(spe):e20190520, 2020. tab, graf.
Idioma: en.
Projeto: National Council for Scientific and Technological Development; . Araucaria Foundation.
Resumo: Abstract Conservation agriculture practices can contribute to changes in soil nutrient dynamics over time. This experiment evaluated the changes in total stocks and distribution of carbon, nitrogen, phosphorus and sulfur concentrations in soil, during 60 months, in an integrated crop-livestock system (ICLS) due to anticipated fertilization of sources and doses phosphates applied in soil surface. The experiment was conducted over a period of five years, under Typic Dystrudept, using a randomized block design, in an incomplete factorial scheme (3×3+1), with four replications. Treatments consisted of three sources of P [triple superphosphate (TSP), rock phosphate - Arad (RP) and magnesium thermophosphate (MTP)], along with four doses of P (0, 60, 120 and 180 kg ha-1 P2O5 total). Samples of soil were collected in 0-5, 5-10, 10-15, 15-20 and 20-30 cm layers at 24, 36, 48 and 60 months after beggining of experiment where the following chemical attributes were evaluated: (i) total organic carbon (TOC); (ii) total nitrogen Kjeldahl (TNK); (iii) available P by ion exchange resin method (P-IER); and (iv) available S-SO4 2-. The ICLS conditions provided increased total stocks and concentrations of TOC, TNK, P-IER and S-SO4 2- over time. The applications of different phosphates had no influence on soil TOC concentrations during the five years of experimentation. The concentrations of TNK, P-IER and S-SO4 2- showed an increase in different layers of soil, with the application of sources and doses of P. The P fertilization practice that was anticipated can consist of an efficient management of soil fertility, using properly managed conservation systems.
Descritores: Fosfatos/administração & dosagem
Solo/química
Cultivos Agrícolas
Análise do Solo
Fertilizantes
Criação de Animais Domésticos
-Fósforo/análise
Enxofre/análise
Carbono/análise
Nitrogênio/análise
Limites: Humanos
Animais
Responsável: BR1.1 - BIREME


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Id: biblio-907786
Autor: Campuzano Maya, Germán.
Título: Las pruebas de aliento con isótopos marcados con carbono 13: una nueva herramienta de diagnóstico, costo-eficiente y con seguridad para el paciente / Breath tests isotopically labeled with carbon 13: a new diagnostic tool, cost-efficient and safe to patient
Fonte: Med. lab;21(9/10):409-412, 2015.
Idioma: es.
Resumo: A la mayoría de las personas a las que se les menciona una prueba de aliento inmediatamente les viene a la mente la visión de un policía de tránsito en medio de un retén, comprobando con un instrumento si el conductor de un vehículo ha consumido bebidas alcohólicas. El conductor sospechoso debe soplar en un pequeño dispositivo manual que, al cabo de unos segundos, indica la cantidad de etanol que está circulando en su sangre. Esta visión es real pero sólo es una de las múltiples aplicaciones de las pruebas de aliento. El aliento, como objeto de análisis, similar a la sangre o la orina, no es nuevo: desde los tiempos de Hipócrates, los médicos han sabido que el aroma de la respiración humana puede proporcionar pistas para el diagnóstico de múltiples enfermedades. El buen clínico conoce el olor dulce y afrutado de la acetona en el aliento de pacientes con diabetes mellitus no controlada, el olor a humedad y a pescado en pacientes con enfermedad hepática avanzada, el olor a orina fermentada característico de las enfermedades renalesterminales y, el hedor pútrido de un absceso pulmonar. La diferencia de aquellos médicos y los de hoy es el instrumento que tienen para leer el aliento: el olfato, finamente entrenado, en los primeros y los instrumentos, de alta tecnología y excelente desempeño analítico, en los segundos...
Descritores: Carbono
Isótopos de Carbono
Doença
Substratos para Tratamento Biológico
Limites: Humanos
Tipo de Publ: Editorial
Responsável: CO373.9 - EDIMECO - Editora Médica Colombiana S.A.



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