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1.
Environ Sci Pollut Res Int ; 31(24): 35083-35114, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38720123

RESUMO

The BRICS countries-Brazil, Russia, India, China, and South Africa-are committed to achieving United Nations Sustainable Development Goal 13, which focuses on mitigating climate change. To attain this goal, it is crucial to emphasize the significance of ICT, renewable energy sources, industrialization, and institutional quality. This study contributes to the literature by examining the potential role of these factors in environmental sustainability in the BRICS economies from 2000 to 2021, utilizing cross-sectional augmented autoregressive distributed lag (CS-ARDL) estimation and other novel econometric techniques. Accordingly, the study suggests that BRICS governments and policymakers prioritize the use of ICT in the industrial and institutional sectors to achieve faster environmental sustainability in the short-run, as per the CS-ARDL results. However, the study advises caution in the long-term as the interaction between ICT and renewable energy sources, industrialization, and institutional quality may not favour environmental quality. Although the renewable energy sources interaction with ICT may not yield immediate progress, strong measures need to be taken to ensure that short-term gains are not nullified. In conclusion, the study highlights the potential of ICT, renewable energy sources, industrialization, and institutional quality in achieving environmental sustainability in the BRICS countries, while recommending cautious measures in the long run to safeguard the progress made.


Assuntos
Desenvolvimento Industrial , Energia Renovável , China , Índia , Brasil , Federação Russa , Desenvolvimento Sustentável , África do Sul , Mudança Climática , Conservação dos Recursos Naturais
2.
Heliyon ; 9(11): e21534, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38045164

RESUMO

This study analyzes public perception towards the energy transition and decarbonization in Chile, and how these preferences change with political ideology, as well as distance between power plant installations and people's homes. Due to a lack of scientific research on civil society preferences for energy production in Chile, we used a convenience sample and conducted a survey among future decision makers (current university students) to identify which factors impact their acceptance or rejection of energy sources. In addition, we asked them about their vision for the future energy mix. In total, 164 valid questionnaires were collected. Results show that the level of acceptance and preference changes with political ideology, with social liberals being more willing to change their lifestyle and increase their willingness to pay for a faster inclusion of clean technologies in the energy mix. Higher levels of education increase this willingness to pay. The level of acceptance decreases up to 56% for solar and wind when the installation is located within a radius less than 5 km from the population's homes. The level of rejection is 97% for hydroelectricity and 99% for non-renewable power plants if they are located at distances lower than 5 km. The decentralization of energy policy decisions and the consideration of local society would be relevant for an energy transition towards renewable sources.

3.
Heliyon ; 9(10): e19874, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37771531

RESUMO

Using renewable energies is a global strategy to mitigate the acceleration of global warming generated by industrial processes and is a sustainable way to diversify the energy matrix in all countries. Biomass is a renewable energy source that produces biofuels and generates electricity and heat. The primary purpose of this work is to identify the municipalities in Colombia where agricultural, livestock, and urban residual biomass could be suitable for energy generation in a sustainable and renewable way. To that end, we carried out a Geostatistical Multi-Criteria Decision Methodology using Analytical Hierarchy Processes such as Rank-Sum and Weighted Linear Combination, as well as considering a set of sustainable development indicators applied to official Colombian data. Two scenarios are considered for comparison purposes. The first one is according to expert criteria, and the second one considers The Sustainable Development Goals proposed by the United Nations. Under both proposed scenarios, 127 municipalities were found to be suitable for agricultural-urban residual biomass and 162 for livestock-urban residual biomass for energy generation. One of the main limitations for the use of urban biomass is that municipalities need to have sufficient production potential to fulfill their own energy needs. An additional comparison with previous works to evaluate the performance of the Multi-Criteria Decision Methodologies MCDM is also proposed.

4.
J Fish Biol ; 101(6): 1530-1539, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36196976

RESUMO

Although many upstream effects of a dam on the trophic ecology of fish have been reported, little is known about their downstream effects on the isotopic niche of Amazonian predator fish. The authors used stable isotope analysis of δ13 C and δ15 N to determine the downstream effects of damming of the Uatumã River on the niche width, carbon energy sources and trophic position of peacock bass Cichla temensis comparing with a free-flowing river in the Amazon basin, Brazil, during the peak flood and early falling water period of 2020. They found that the C. temensis population of the undammed river had a smaller niche width than the C. temensis population of the dammed river, despite the greater number of prey trophic levels utilized and the higher trophic position of C. temensis individuals. The results demonstrate that in both rivers there is a gradual shift in the contribution of prey fish sources to the diet of C. temensis throughout its growth, even among adult individuals. They conclude that the isotopic niche of C. temensis was altered by damming during the period of late high water to early low water in the Uatumã River.


Assuntos
Ciclídeos , Água , Animais , Rios , Carbono , Dieta
5.
Front Vet Sci ; 9: 945542, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36157190

RESUMO

Enteral fluid therapy administered in continuous flow through the naso-ruminal route for long periods with electrolyte solutions is safe and effective in cattle. The aim of this study was to carry out a comparative assessment between maintenance enteral electrolyte solutions containing calcium propionate, propylene glycol or glycerol administered in continuous flow in cattle. Six heifers were used and the study was carried out in a 6 × 3 crossover design, in which each animal received three different treatments: enteral electrolyte solution containing calcium propionate (ESCaP), enteral electrolyte solution containing glycerol (ESGly) and enteral electrolyte solution containing propylene glycol (ESPrG). Solutions were administered at a rate of 15 mL kg-1 h-1 for 12 h. Serum and urinary biochemical assessment; urinary volume, pH, and specific gravity; and blood gas analysis were measured at 0, 3, 6, 9, 12, and 24 h. All three enteral electrolyte solutions expanded blood volume and increased urine volume without causing electrolyte imbalances. ESCaP caused mild reversible metabolic alkalosis while the most significant glycemic potential was observed in electrolyte solutions containing propylene glycol (ESPrG) and calcium propionate (ESCaP).

6.
Data Brief ; 39: 107513, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34765705

RESUMO

This article presents the weather and power data files from renewable sources used to solve the economic dispatch problem of a microgrid that operates in the isolated and grid-connected modes. Methodology is used in the research article "Management of an island and grid-connected microgrid using hybrid economic model predictive control with weather data" (Silva et al., 2020). Automatic stations located in the Brazil's south and northeast furnished the weather data (global horizontal irradiance, temperature, and wind speed). A script generates files containing weather forecasts from one-day ahead using the geographical coordinates of the weather stations. Hybrid models, characterized by real and binary variables, use the weather forecasting data to calculate the photovoltaic and wind power forecasts. A microgrid management algorithm uses these forecasts to solve the optimal economic dispatch problem. This data-in-brief paper presents five datasets for each weather station: (i) Weather dataset downloaded from the website of the National Meteorological Institute, (ii) Weather research and forecasting (WRF) dataset derived from the raw data generated by the weather research and forecasting model, (iii) Weather dataset that joins the forecasted data with the measured data in a single file, (iv) Handled dataset that treats some gaps in the weather dataset and converts it to other formats, (v) Files containing only the temperature, global horizontal irradiance, and wind speed data, (vi) Files containing the measured and forecasted wind and solar power.

7.
Heliyon ; 7(9): e07959, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34553088

RESUMO

This work is focused on the importance of developing and promoting the use of wind and solar energy resources in the Colombian Caribbean coast. This region has a considerable interest for the development of solar technology due to the available climatic characteristics. Therefore, a detailed solarimetric analysis has been carried out in the department of San Andrés, Providencia and Santa Catalina, located in the Colombian Caribbean region, using a semi-empirical radiation model, based on the Bird & Hulstrom model, and the parameterizations of the Mächler & Iqbal model, which allowed obtaining an average total irradiation value of 6.5 kWh/m2day. In addition, a statistical analysis of the wind resource was carried out based on meteorological data, which yielded an average multiannual wind speed of 3.4 m/s, and a maximum wind speed of 15.2 m/s during the month of October. The meteorological input data used for this analysis were provided by the Colombian Institute of Hydrology, Meteorology and Environmental Studies (IDEAM), in order to perform initial calculations and obtain a climatic profile of the areas with clear, medium and cloudy atmospheres throughout the year. Regarding the comparative study, the analysis was complemented with a prediction of solar radiation using Artificial Neural Networks (ANN), where irradiance could be predicted with a fairly good agreement, which was validated with a Root Mean Square Error (RMSE) of 0.87 using the temperature, the relative humidity, the pressure and the wind speed as the input data.

8.
Rev. colomb. cir ; 36(4): 626-636, 20210000. fig, tab
Artigo em Espanhol | LILACS | ID: biblio-1291156

RESUMO

Introducción. La apendicectomía por laparoscopia se considera el patrón de oro en el tratamiento de la apendicitis aguda. Sin embargo, su disponibilidad es limitada en nuestro sistema de salud, principalmente por los costos asociados. El objetivo de este estudio fue evaluar la relación entre el uso de los diferentes tipos de energía y los métodos de ligadura de la base apendicular, con las complicaciones postoperatorias, al igual que describir los costos asociados. Métodos. Estudio observacional analítico de una cohorte retrospectiva de pacientes mayores de 15 años a quienes se les realizó apendicectomía por laparoscopia, en un hospital universitario entre los años 2014 y 2018. Se utilizaron modelos de regresión logística y lineal para evaluar la relación entre métodos de ligadura del meso y base apendicular, desenlaces operatorios y costos. Resultados. Se realizaron 2074 apendicectomías por laparoscopia, 58,2 % (n=1207) en mujeres, la edad mediana fue de 32 años. En el 71,5 % (n=1483) la apendicitis aguda no fue complicada. La energía monopolar para la liga-dura del meso apendicular fue la utilizada más frecuentemente en 57,2 % (n=1187) y el Hemolok® el más utilizado para la ligadura de la base apendicular en el 84,8 % (n=1759) de los pacientes. No se observaron diferencias estadísticamente significativas en la tasa de infección del sitio operatorio, reintervención o íleo. El uso de energía simple redujo los costos del procedimiento de manera significativa durante el período evaluado. Discusión. El uso de energía monopolar demostró ser una técnica segura, reproducible y de menor costo en comparación con el uso de energía bipolar, independientemente de la fase de la apendicitis aguda. Lo anterior ha permitido que se realicen más apendicectomías por laparoscopia y que los médicos residentes de cirugía general puedan realizar procedimientos laparoscópicos de forma más temprana


Introduction. Laparoscopic appendectomy is considered the gold standard in the treatment of acute appendicitis. However, its availability is limited in our health system mainly due to the associated costs. The objective of this study is to evaluate the relationship between the use of different types of energy and the methods of ligation of the appendicular base with postoperative complications, as well as to describe the associated costs. Methods. Retrospective observational study of a cohort of patients older than 15 years old who underwent laparoscopic appendectomy in a university hospital between 2014 and 2018. Logistic and linear regression models were used to evaluate the relationship between methods of ligation of the meso and appendicular base, operative outcomes and costs. Results: 2074 laparoscopic appendectomies were performed. Of those, 58.2% (n=1207) were women, median age was 32 years. In 71.5% (n=1483), acute appendicitis was uncomplicated. Monopolar energy for ligation was the most frequently used for ligation of the appendicular meso in 57.2% (n=1187) and Hem-o-lok® the most used for ligation of the appendicular base in 84.8% (n=1759) of the patients. There were no statistically significant differences in the rate of surgical site infection, reoperation, or ileus. The use of simple energy reduced the costs of the procedure significantly during the study period. Discussion. The use of monopolar energy proved to be a safe, reproducible and a lower cost technique compared to the use of bipolar energy, regardless of the phase of acute appendicitis. This has allowed more laparoscopic appendectomies to be performed and the general surgery residents to perform laparoscopic procedures earlier


Assuntos
Humanos , Apendicite , Laparoscopia , Apendicectomia , Fontes de Energia Bioelétrica , Controle de Custos , Ligadura
9.
Micromachines (Basel) ; 12(6)2021 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-34199196

RESUMO

In this paper, a high step-up boost converter with a non-isolated configuration is proposed. This configuration has a quadratic voltage gain, suitable for processing energy from alternative sources. It consists of two boost converters, including a transfer capacitor connected in a non-series power transfer structure between input and output. High power efficiencies are achieved with this arrangement. Additionally, the converter has a common ground and non-pulsating input current. Design conditions and power efficiency analysis are developed. Bilinear and linear models are derived for control purposes. Experimental verification with a laboratory prototype of 500 W is provided. The proposed configuration and similar quadratic configurations are compared experimentally using the same number of components to demonstrate the power efficiency improvement. The resulting power efficiency of the prototype was above 95% at nominal load.

10.
Braz. arch. biol. technol ; Braz. arch. biol. technol;64(spe): e21200734, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1285561

RESUMO

Abstract The State of Paraná stands out in Brazil for its hydraulic potential for electricity generation. Furthermore, the State also shows potential for the use of other sources of energy, such as solar energy, biogas and biomass. The study traces the profile of electric energy consumption and compiles analysis of the alternative energy potentials of Paraná on the use of solar energy, the biomass of forest residues and agricultural crops, the generation of biogas through the residues of farmed animals and the urban solids residues. The work took account for the estimates, the logistical limitations for the biomass or biogas collection and the real availability of the wastes in terms of viability of exploration through distributed generation plants. The use of the business analytics software Tableau Desktop 2020.3.2® made possible the open data analysis at the municipal level. The paper provides realistic estimates about the feasibility of the use of alternative energy sources in the State of Paraná.


Assuntos
Fontes Geradoras de Energia , Energia Renovável , Brasil , Análise de Dados
11.
Pesqui. vet. bras ; 38(8): 1691-1695, Aug. 2018. tab
Artigo em Português | VETINDEX | ID: vti-22330

RESUMO

Objetivou-se com este estudo comparar os efeitos do fornecimento de dietas glicogênicas ou lipogênicas sobre metabolitos sanguíneos e hormônios em vacas primíparas (n=40) durante o período de transição. Os animais foram aleatoriamente distribuídos em quatro tratamentos: controle, sais de cálcio de ácidos graxos poli-insaturados (Megalac-E, 100g pré-parto e 250g pós-parto), soja tostada (400g pré-parto e 800g pós-parto) e propilenoglicol (300ml pré e pós-parto). Os suplementos foram fornecidos individualmente. Foram realizadas coletas de sangue para determinação das concentrações plasmáticas de insulina, glicose, ácidos graxos não esterificados (AGNE) e IGF-I. As concentrações de insulina e de glicose foram maiores nos animais do tratamento com sais de cálcio de ácidos graxos poli-insaturados. A maior concentração de AGNE foi observada no grupo controle. A concentração plasmática de IGF-I foi mais elevada para os animais do tratamento que receberam suplementos lipogênicos. A adição de sais de cálcio de ácidos graxos poli-insaturados a dieta foi capaz de amenizar as mudanças hormonais e metabólicas características do período de transição.(AU)


The aim of this study was to compare the effects of glycogenic supply or lipogenic diets on blood metabolites and hormones in primiparous dairy cows (n=40) during the transition period. The animals were randomly assigned to four treatments: control, calcium salts of polyunsaturated fatty acids (Megalac-E, 100g prepartum and 250g postpartum), roasted soybeans (400g prepartum and 800g postpartum) and propylene glycol (300ml pre- and postpartum). The supplements were provided individually. Blood samples were taken to determine plasma concentrations of insulin, glucose, non-esterified fatty acids (NEFA) and IGF-I. The glucose and insulin concentrations were higher in calcium salts of polyunsaturated fatty acids treatment. The highest concentration of NEFA was observed in the control group. The plasma concentrations of IGF-I were higher for the treatments with lipogenic supplements. Adding calcium salts of polyunsaturated fatty acids diet was able to ease the hormonal and metabolic changes of the transition period features.(AU)


Assuntos
Animais , Feminino , Bovinos , Bovinos/metabolismo , Bovinos/sangue , Materiais Suplementares Eletrônicos
12.
Pesqui. vet. bras ; Pesqui. vet. bras;38(8): 1691-1695, Aug. 2018. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-976484

RESUMO

Objetivou-se com este estudo comparar os efeitos do fornecimento de dietas glicogênicas ou lipogênicas sobre metabolitos sanguíneos e hormônios em vacas primíparas (n=40) durante o período de transição. Os animais foram aleatoriamente distribuídos em quatro tratamentos: controle, sais de cálcio de ácidos graxos poli-insaturados (Megalac-E, 100g pré-parto e 250g pós-parto), soja tostada (400g pré-parto e 800g pós-parto) e propilenoglicol (300ml pré e pós-parto). Os suplementos foram fornecidos individualmente. Foram realizadas coletas de sangue para determinação das concentrações plasmáticas de insulina, glicose, ácidos graxos não esterificados (AGNE) e IGF-I. As concentrações de insulina e de glicose foram maiores nos animais do tratamento com sais de cálcio de ácidos graxos poli-insaturados. A maior concentração de AGNE foi observada no grupo controle. A concentração plasmática de IGF-I foi mais elevada para os animais do tratamento que receberam suplementos lipogênicos. A adição de sais de cálcio de ácidos graxos poli-insaturados a dieta foi capaz de amenizar as mudanças hormonais e metabólicas características do período de transição.(AU)


The aim of this study was to compare the effects of glycogenic supply or lipogenic diets on blood metabolites and hormones in primiparous dairy cows (n=40) during the transition period. The animals were randomly assigned to four treatments: control, calcium salts of polyunsaturated fatty acids (Megalac-E, 100g prepartum and 250g postpartum), roasted soybeans (400g prepartum and 800g postpartum) and propylene glycol (300ml pre- and postpartum). The supplements were provided individually. Blood samples were taken to determine plasma concentrations of insulin, glucose, non-esterified fatty acids (NEFA) and IGF-I. The glucose and insulin concentrations were higher in calcium salts of polyunsaturated fatty acids treatment. The highest concentration of NEFA was observed in the control group. The plasma concentrations of IGF-I were higher for the treatments with lipogenic supplements. Adding calcium salts of polyunsaturated fatty acids diet was able to ease the hormonal and metabolic changes of the transition period features.(AU)


Assuntos
Animais , Feminino , Bovinos , Bovinos/metabolismo , Bovinos/sangue , Materiais Suplementares Eletrônicos
13.
Electron. j. biotechnol ; Electron. j. biotechnol;33: 52-62, May. 2018. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1025045

RESUMO

The use of nonrenewable energy sources to provide the worldwide energy needs has caused different problems such as global warming, water pollution, and smog production. In this sense, lignocellulosic biomass has been postulated as a renewable energy source able to produce energy carriers that can cover this energy demand. Biogas and syngas are two energy vectors that have been suggested to generate heat and power through their use in cogeneration systems. Therefore, the aim of this review is to develop a comparison between these energy vectors considering their main features based on literature reports. In addition, a techno-economic and energy assessment of the heat and power generation using these vectors as energy sources is performed. If lignocellulosic biomass is used as raw material, biogas is more commonly used for cogeneration purposes than syngas. However, syngas from biomass gasification has a great potential to be employed as a chemical platform in the production of value-added products. Moreover, the investment costs to generate heat and power from lignocellulosic materials using the anaerobic digestion technology are higher than those using the gasification technology. As a conclusion, it was evidenced that upgraded biogas has a higher potential to produce heat and power than syngas. Nevertheless, the implementation of both energy vectors into the energy market is important to cover the increasing worldwide energy demand.


Assuntos
Biocombustíveis/análise , Lignina/metabolismo , Centrais Elétricas , Digestão Anaeróbia , Biomassa , Energia Renovável , Temperatura Alta , Lignina/química , Metano
14.
Braz. arch. biol. technol ; Braz. arch. biol. technol;61(spe): e18000015, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-974135

RESUMO

ABSTRACT Sludge oil derived from the effluent generated in poultry abattoirs offers a promising biomass for the production of biodiesel. In this work, determination was made of its physicochemical characteristics, including acidity, density at 20ºC, peroxide index, moisture content, and saponification index, together with evaluation of a route for its conversion to biodiesel.


Assuntos
Biocombustíveis , Matadouros , Biomassa , Energia Renovável
15.
Rev. bras. ciênc. avic ; 19(3): 363-370, July-Sept. 2017. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1490441

RESUMO

ABSTRACT This paper intends to outline a model of multi-criteria analysis to pinpoint the most suitable energy source for heating aviaries in poultry broiler production from the point of view of the farmer and under environmental logic. Therefore, the identification of criteria was enabled through an exploratory study in three poultry broiler production units located in the mountain region of Rio Grande do Sul. In order to identify the energy source, the Analytic Hierarchy Process was applied. The criteria determined and validated in the research contemplated the cost of energy source, leadtime, investment in equipment, energy efficiency, quality of life and environmental impacts. The result of applying the method revealed firewood as the most appropriate energy for heating. The decision support model developed could be replicated in order to strengthen the criteria and energy alternatives presented, besides identifying new criteria and alternatives that were not considered in this study.


Assuntos
Animais , Aves Domésticas/anormalidades , Aves Domésticas/crescimento & desenvolvimento , Aves Domésticas/metabolismo
16.
R. bras. Ci. avíc. ; 19(3): 363-370, July-Sept. 2017. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: vti-13864

RESUMO

ABSTRACT This paper intends to outline a model of multi-criteria analysis to pinpoint the most suitable energy source for heating aviaries in poultry broiler production from the point of view of the farmer and under environmental logic. Therefore, the identification of criteria was enabled through an exploratory study in three poultry broiler production units located in the mountain region of Rio Grande do Sul. In order to identify the energy source, the Analytic Hierarchy Process was applied. The criteria determined and validated in the research contemplated the cost of energy source, leadtime, investment in equipment, energy efficiency, quality of life and environmental impacts. The result of applying the method revealed firewood as the most appropriate energy for heating. The decision support model developed could be replicated in order to strengthen the criteria and energy alternatives presented, besides identifying new criteria and alternatives that were not considered in this study.(AU)


Assuntos
Animais , Aves Domésticas/anormalidades , Aves Domésticas/crescimento & desenvolvimento , Aves Domésticas/metabolismo
17.
Waste Manag ; 65: 75-91, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28410889

RESUMO

This study aimed to determine theoretically, the electrical optimum power of LFG using the maximum net benefit (MNB) methodology, and taking into consideration the economic, demographic, and regional aspects of the Inter municipal Consortium of the Micro-region of the High Sapucaí for Sanitary Landfill (CIMASAS, as acronym in Portuguese), that is located in the southern part of the State of Minas Gerais, Brazil. To this end, the prognosis for a 20-year period of household solid waste generation in this region was estimated and quantified based on population data, in order to estimate the LFG production and the energy that can be generated. From this point, the optimum power for thermal power plant (TPP) by LFG was determined. The results indicated that the landfill in this region could produce more 66,293,282m3CH4 (with maximum power of 997kW in 2036) in twenty years and that there would be no economic viability to generate energy from LFG, because the Net Present Value (NPV) would not be positive. The smallest population to that can achieve a minimum attractiveness rate (MAR) of 15% should be 3,700,000 inhabitants under the conditions studied. Considering the Brazilian National Electric Energy Agency (ANEEL) Resolutions, it would be 339,000 inhabitants with an installed power of 440kW. In addition, the outcome of the CIMASAS case-study demonstrated the applicability of MNB methodology for the determination of TPP optimum power.


Assuntos
Biocombustíveis , Centrais Elétricas , Instalações de Eliminação de Resíduos , Brasil , Eliminação de Resíduos , Resíduos Sólidos
18.
Rev. bras. med. trab ; 15(1): 29-41, jan.-mar. 2017.
Artigo em Português | LILACS | ID: biblio-833585

RESUMO

Contexto: O metanol é usado como matéria-prima na fabricação de biodiesel e pode causar, em especial, danos oftalmológicos e neurológicos. A exposição ocupacional acontece principalmente pela inalação de vapores. No entanto, os dados relacionados aos efeitos da exposição crônica ao metanol em humanos são limitados. Objetivos: Mostrar situações e atividades com risco de exposição ao metanol em uma planta de biodiesel e a presença de possíveis sintomas de contaminação nos trabalhadores. Métodos: Questionário, entrevistas, observação direta e análise documental possibilitaram a coleta dos dados. Resultados: O processo produtivo apresentou oito situações de exposição ao metanol. Entre os 42 sujeitos da pesquisa, 27 trabalhavam diretamente expostos e rela-taram ter dor de cabeça (71,42%), formigamento (42,00%), entre outros sintomas. As mais importantes queixas relacionadas com os efeitos neurotóxicos foram irritação (40,50%), ansiedade (35,70%) e dor de cabeça (64,30%). Funcionários das áreas administrativas também apresentavam sintomatologia idêntica à de contaminação pelo químico. Conclusões: Trabalhadores em diferentes atividades estavam expostos ao metanol, e a análise dos sintomas associados à exposição a esse solvente revelou que a maioria apresentava alguma sintomatologia compatível com a contaminação por ele.


Background: Methanol is used as raw material for biodiesel production and might cause especially visual and neurological disorders. Occupational exposure mainly occurs through vapor inhalation. However, the available data on the effects of human chronic exposure to methanol are limited. Aims: To describe situations and activities involving risk of exposure to methanol in a biodiesel plant and the possible presence of symptoms of contamination in workers. Methods: Data collection was performed by means of direct observation, interviews, document analysis and application of a questionnaire. Results: The production process included eight different situation os methanol exposure. Among the 42 participants in the study, 27 worked under conditions of direct methanol exposure and reported headache (71.42%) and tingling (42.00%) among other symptoms. The most important complaints related to the neurotoxic effects of methanol were irritation (40.50%), anxiety (35.70%) and headache (64.30%). Similarly, workers in administrative areas exhibited the same symptoms of contamination by the chemical. Conclusions: Workers performing various different activities were exposed to methanol; analysis of the symptoms associated with exposure to the solvent showed that most of them exhibited symptoms compatible with methanol contamination.


Assuntos
Riscos Ocupacionais , Metanol/toxicidade , Fontes Geradoras de Energia , Biocombustíveis/toxicidade , Poluição Ambiental , Coleta de Dados/instrumentação
19.
Anim Nutr ; 2(3): 149-153, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29767007

RESUMO

The experiment aimed at determining the nutritional value of integral cassava root silages with yogurt as inoculant or wastewater (manipueira) by liquid addition ensiling process. Eighteen crossbred piglets (Large White × Landrace), castrated males with an initial average weight of 50 kg were allocated in metabolism cages throughout 11-day trial duration (6 days for animal's adaptation to the cages and to the experimental diets, and 5 days of urine and faeces collection). The experimental design was a randomized block arrangement with 3 treatments and 6 replicates: basal diet (100%); mixture composed of 75% basal diet and 25% integral cassava root silage with yogurt as inoculant; a mixture composed of 75% of basal diet and 25% integral cassava root silage with wastewater. The silages with wastewater and yogurt presented the following values of apparent digestibility of dry matter 89.96% and 90.01%, apparent digestibility of crude protein of 60.67% and 66.43%, apparent digestibility of gross energy of 90.43% and 91.48%, gross energy metabolizability coefficients of 87.88% and 88.93%, digestible energy values of 3,705 and 3,783 kcal/kg on a dry matter (DM) basis, and metabolizable energy values of 3,600 and 3,676 kcal/kg DM, respectively. The results have demonstrated that integral cassava root silages with wastewater or yogurt have a high nutritional value and can be used as an alternative energy source in growing pig's diets.

20.
Rev. MVZ Córdoba ; 20(2): 4513-4521, May-Aug. 2015. ilus, tab
Artigo em Inglês | LILACS, COLNAL | ID: lil-759095

RESUMO

Objective. The study aimed to evaluate the effect of sows' of different parities and the supplement of coconut oil for piglets, on the development of litter. Materials and methods. A total of 51 sows of different parities and their 642 piglets were used in the trial. Each piglet was weighed and identified at birth in a sequential order. They were randomly distributed in two treatments (CG=control group and TG=test group). TG piglets had the first access to a dosage of 3.0 ml of coconut oil 12 hours after birth, and the second at 36 h after the first. Piglets were weighed at 21 days. In order to analyze the effect of the coconut oil supplement as a function of the weight at birth, piglets were grouped according to their weight (0.600 to 0.900 kg; 1.000 to 1.499kg; 1.500 to 1.999 kg; and 2.000 to 2.499 kg). Results. Sows parity affected the number and weight of born piglets. Sows in 4th, 5th and 7th parity had a larger litter than those from the 2nd parity. Sows from 2nd and 3rd parity had a lower number of piglets but heavier litter. No effect of the coconut oil supplement on neonatal piglets' performance was found. Conclusions. The coconut meal was neither beneficial to neonatal piglets nor to those with low weight at birth, which usually present low body energy.


El objetivo del estudio fue evaluar el efecto del número de partos y el suplemento de aceite de coco en lechones recien nacidos. Materiales y métodos. Se utilizaron 51 cerdas de diferentes partos y sus 642 lechones. Cada lechón se pesó y se identificó al nacer en orden secuencial. Fueron distribuidos aleatoriamente en dos grupos (CG = control y TG=tratamiento). Lechones TG tenían el primer acceso a una dosis de 3.0 ml de aceite de coco 12 horas después del nacimiento, y el segunda a las 36 h después de la primera. Los lechones fueron pesados a los 21 días. Con el fin de analizar el efecto de los suplementos de aceite de coco con relación al peso al nacer. Los lechones fueron agrupados de acuerdo con su peso (0.600 a 0.900 kg; 1.000 a 1.499 kg; 1.500 a 1.999 kg y 2.000 a 2.499 kg). Resultados. El número de partos afectó el peso y el número de lechones nacidos. Cerdas en cuarto, quinto y séptimo parto, tuvieron una camada mayor que las de segundo parto. Las cerdas de segundo y tercer parto tuvieron menor número de lechones y con peso mayor. No se encontró efecto del suplemento de aceite de coco en el desarrollo de los lechones recién nacidos. Conclusiones. Lo aceite de coco no es favorable para los lechones recién nacidos, tampoco para aquellos con el bajo peso al nacer, que normalmente presentan la energía corporal baja.


Assuntos
Ácidos Graxos , Animais Recém-Nascidos , Fontes de Energia Elétrica , Tamanho da Ninhada de Vivíparos
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