917 research outputs found
Review of the safety of octocrylene used as an ultraviolet filter in cosmetics
Octocrylene or octocrilene is an organic ultraviolet (UV) filter which absorbs mainly UVB radiation and short UVA wavelengths. It is used in various cosmetic products to either provide an appropriate sun protection factor in sunscreen products or to protect cosmetic formulations from UV radiation. There is no discussion that UV filters are beneficial ingredients in cosmetics since they protect from skin cancer, but octocrylene has been recently incriminated to potentially induce adverse effects on the endocrine system in addition to having allergic and/or photoallergic potential. However, the substance has the advantage to work synergistically with other filters allowing a beneficial broad photoprotection, e.g. it stabilizes the UVA filter avobenzone (i.e. butylmethoxydibenzoylmethane). Like all chemicals used in cosmetics, the safety profile of octocrylene is constantly under assessment by the European Chemical Agency (ECHA) since it has been registered according to the European regulation Registration, Evaluation, Authorisation and Restriction of Chemicals. Summaries of safety data of octocrylene are publicly available on the ECHA website. This review aims to present the main safety data from the ECHA website, as well as those reported in scientific articles from peer-reviewed journals. The available data show that octocrylene does not have any endocrine disruption potential. It is a rare sensitizer, photocontact allergy is more frequent and it is considered consecutive to photosensitization to ketoprofen. Based on these results, octocrylene can be considered as safe when used as a UV filter in cosmetic products at a concentration up to 10%
Propiedades, ventajas e inconvenientes de los materiales utilizados en supercondensadores
Este trabajo recoge una visión general de las propiedades, ventajas e inconvenientes de los principales materiales usados en los electrodos de los condensadores electroquímicos (también denominados supercondensadores). La elección de estos materiales tiene una enorme influencia en las características finales del dispositivo electroquímico. Entre los materiales de electrodo disponibles para su aplicación en supercondensadores se incluyen los materiales porosos basados en carbón, los óxidos de metales de transición y los polímeros conductores. Cada una de estas familias de materiales presenta unas ventajas e inconvenientes, por ello, en numerosas ocasiones no se emplea un único tipo de material para la elaboración de los electrodos, sino que la tendencia va dirigida hacia el uso de electrodos híbridos, es decir, aquellos constituidos por materiales de distinta naturaleza que combinan los aspectos beneficiosos y compensan las limitaciones de cada uno de los materiales por separado
Introduction of Brachiaria brizantha cv. Marandú for Milk Production, and Economic Results of a Buffalo Dairy
The effect of introducing Brachiaria brizanta cv. Marandú for forage upon milk production and economic results was evaluated on Tayabito buffalo dairy farm affiliated to Maraguán Livestock Center in Camagüey municipality, Cuba. To this purpose, a two-hectare B. brizanta grazing ground was introduced and its effect on milk production and quality was estimated by a Switch Back design with two treatments and six replicas each. Initially, female buffaloes lactation span was 122 ± 5,7 days. Forage balances were performed on native pastures and half the area with B. brizanta grassland. This new species proved its suitability by spreading over 80 % of the 2 ha area after being planted. Concerning milk production during dry and rainy seasons, a significant increase was registered for B. brizanta compared to native pastures (over 0,54 and 0,83 l/animal/day for each season, respectively). Milk quality was not affected in either case. This farm forage production could supply current herd feeding needs by introducing 50 % grazing grounds of B. brizanta; besides, productive indexes could significantly improve
Efficiency of Agricultural Upgrading as a Component of the Farming Extension System
Evaluation was effected through a participative-diagnosis tool which integrates several techniques and the organ- izational work for agro producer training. Three participative exercises, i.e., brainstorming, questions, and the nine- square or the General Electric matrix, were performed. Deficiencies in the training process and how to solve them, the need of team work to diagnose demands, problems, program design, and program application were determined. Besides, the current situation of the School of Training for Agricultural Executives, affiliated to the Ministry of Ag- riculture division in Camagüey, was assessed, for capital and resource investment, and for introduction of new agro- products and services to the market
PRAGACC: A System to Identify Vulnerabilities and Classify Livestock Farms
PRAGACC is a system designed to classify cattle units, determine their weaknesses and make decisions to miti- gate them. This system is composed of two matrixes or subsystems: (I) natural resources and (II) other resources. Each matrix comprises the following variables: microclimate (A), soil (B), hydrology (C), flora and vegetation (D), and on-production animals (E) for subsystem I, and economy (F), production (G), and human resources (H) for subsystem II. Variables are determined according to 26 and 28 components for subsystems I and II, respectively. Criteria to evaluate each variable were gathered by applying a 34-question inquiry to a farmer from the studied cattle unit. A previously fixed value for each answer according to the questions contributed to the answer-related components and these, in turn, to the variables. Units classification under a subsystem depends on the number of variables showing any kind of weakness. This classification is useful in determining measures to be implemented and their priority
Evaluation of Fattening Efficiency of Grazing Bulls through Panel Data Envelop Analysis
The purpose of this paper was to assess fattening efficiency changes in grazing bulls, using panel data envelop analysis in two periods of time. The panel data were compiled by DEAP 2.1, which included the results of a 3-year period from 38 private farms (beef farms) in cooperatives of credits and services. The farms were on prairie savannahs, located on 21.4831 latitude, and -77.3174 longitude, less than 300 meters above sea level, province of Camagüey, mideastern Cuba. The output variable was total sold kg (TSKG), and the input variables were cost of Norgold (CN), fuel kg per ha (FKGXHA), fuel kg per livestock unit (FKGXLU), and unit of human labor force (UHL), which were highly correlated to the output variable. Table 2 shows that technical efficiency (TE), pure efficiency (PEC), and scale sufficiency (SEC), underwent 0.2%, 0.4, and 0.5%, respectively, by the third year of fattening. Technological change (TC) between the second and third years rose to almost 14%, and the total productivity factor (TPF) spiked as farmers became more skilled and experienced, with a 4.9% increase in comparison to the first year, and 13.7% in the second year
Classification of Dairy Farms and Identification of their Weaknesses by the PRAGACC System
Fourteen dairy farms from the Basic Unit of Cooperative Production (UBPC) Patria o Muerte in Camagüey, Cuba, were classified by the PRAGACC system and their principal weaknesses were detected in order to implement mitigation measures. In all farms, deficiencies concerning management of ecosystem elements were detected (subsystem I, natural resources); out of them, five farms were impaired in two variables, six in three variables, and three in four variables. Among the principal deficiencies identified for this subsystem, water availability and its inadequate use, lack of trees on grasslands, and insufficient endogenous sources as alternatives for cattle feeding were the most evident. Regarding subsystem II (others resources), six farms showed an inefficient production process mainly associated with absence of initiatives in finding energy sources and the non-utilization of certain materials for biofertilizers manufacturing. Two other farms were identified as the most affected, thus demanding a higher priority in measures implementation. PRAGACC also increased the likelihood of a priority arrangement for the remaining farms
Balance energético, proteico, forrajero y sostenibilidad en una unidad de producción lechera vacuna
A research was carried out at a livestock dairy production center in Camagüey province, Cuba, comprising 100,9 ha, three of them dedicated to sugar cane sowing and the rest to grazing grounds. Paspalum virgatum, Dychrostachis glomerata, and wastelands cover a 32,1 % of the grazing grounds. Dominant native pasture grasses include Bothriochba pertrusa, Paspalum notatum, Dichanthium caricosum, and Panicum maximum. A balance of energy and of some of the main sustainability factors, within a milk production system was performed. Data recorded at the center were used to study energy and protein balance as well as sustainability factors. A liter of milk was taken as the equivalent to a kilogram of this product. The system energy input (Mcal/years= 109 951,33) was higher than its output (22 378) with a negative balance (87 573,3 Mcal/year). As to raw protein balance, a higher input (7 824,6 kg) and a lower output (3 602,9 kg) with a negative balance (-4 221,7 kg) was also found. Therefore, energy-protein balances are negative, showing energy inputs 8 and 4 fold higher than energy outputs, respectively. It was also proved a number of deficiencies concerning sustainability essential components.La investigación se realizó en una unidad productora de leche en la provincia de Camagüey, Cuba, con un área total de 100,9 ha, de ellas tres destinadas a la siembra de caña y las restantes son utilizadas como pastizal, cuyo 32,1% se encuentra infestado por caguazo (Paspalum virgatum), marabú (Dychrostachis glomerata) y áreas despobladas. Los pastos nativos que predominan son: la camagüeyana (Bothriochloa pertusa), tejana (Paspalum notatun) y jiribilla (Dichanthium caricosum) y la guinea (Panicum maximun). Se realizó un balance de energía y de algunos de los principales factores de sostenibilidad en un sistema de producción de leche. Para estudiar el balance de energía y proteína así como los factores de sostenibilidad se utilizaron los datos obtenidos en la unidad. Se consideró el litro como el equivalente a un kilogramo del mismo producto. La entrada de energía al sistema (Mcal/año = 109 951,33) resultó superior a las salidas (22 378) con un balance negativo 87 573,3 Mcal/año). En el balance de proteína bruta se determinó una entrada superior (7 824,6 kg), con respecto a la salida (3 602,9), que resultó también con balance negativo (-4 221,7 kg). Se concluye que los balances energético-proteico son negativos, donde las entradas de energía superan en 8 y 4 veces a las salidas, respectivamente. Se determinó que la unidad presenta deficiencias en elementos esenciales de sostenibilidad
Fattening Commercial Zebu with Grazing and Low Supplementation on Small Farms.
The aim of this paper was to describe and group grazing commercial Zebu bulls, with low supplementation. Forty-four beef-producing farms from several cooperatives of credits and services were studied. Their members are private farmers from Sibanicu, Camaguey, Cuba. The farms were visited for three years, and official records were made of each farmer for these variables: resources, animals, management, production, and economy. The main statigraph for the variables were calculated. The average initial weight, final weight, weight gain, and production per ha were, 202.6; 371.6; 501; and 326.2 kg, during 339.7 fattening days, respectively. The principal component analysis (PCA) showed a Kaiser-Meyer-Olkin coefficient higher than 0.66, and a significant Bartlett sphericity coefficient (P < 0.01), with self-values above 1. The two groups were made using a BIETAPIC cluster analysis
Estudio cinético e isotérmico de la biosorción de Zinc (II) y Cadmio (II) para un sistema monometálico-bimetálico por Undaria pinnatífida sp
Se estudió la capacidad de adsorción que tiene el alga marina Undaria pinnatifida sp. en la adsorción de los iones metálicos de zinc y cadmio para un sistema individual (monometalico) y en mezclas (bimetálico) de una solución acuosa. Se estudió preliminarmente para este proceso, el tiempo de contacto, pH de la solución y tratamiento del biopolímero. El estudio de la cinética determinó que el comportamiento del sistema de adsorción fue de pseudo segundo orden usando la ecuación de Langergren (concentración inicial 50 mg/L, peso del biopolímero = 0,4g; pH = 3 - 5). El modelamiento no lineal de las isotermas de Langmuir y Freundlich, con el modelo de Langmuir se obtuvo un mejor coeficiente de correlación cercano a la unidad, determinándose que la máxima capacidad de sorción de los iones metales como zinc fue qmax = 44,91 mg/g y cadmio qmax = 102,38 mg/g a pH = 4 en un tiempo de contacto de 60 minutos, con el alga sin tratamiento en el sistema monometálico, siendo más eficiente la adsorción para el ion cadmio. Para el sistema bimetálico se empleó dos métodos: el método de las isoconcentraciones que dio a conocer el comportamiento en la adsorción de ambos metales en solución y el método de las concentraciones variables empleando el análisis de regresión del modelo de Langmuir modificado, que dio a conocer los valores de la capacidad máxima de adsorción, siendo para el ion metálico zinc qmax = 0,27 mmol/g; cadmio qmax= 1,27 mmol/g y para la adsorción de ambos metales sobre la biomasa qmax= 1,13 mmol/gFil: Mori C., M.. Universidad Peruana Cayetano Heredia; PerúFil: Maldonado G., H.. Universidad Nacional Mayor de San Marcos; PerúFil: Guzman L., E. Universidad Nacional Mayor de San Marcos; PerúFil: Eyras, María Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Bernardelli, Cecilia Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigación y Desarrollo En Fermentaciones Industriales (i); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Viera, M.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigación y Desarrollo En Fermentaciones Industriales (i); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Donati, Edgardo Ruben. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigación y Desarrollo En Fermentaciones Industriales (i); Argentin
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