2,342 research outputs found
The New Tendencies of Environmental Impact Assessment of Livestock Production: A Road Testing of LEAP/FAO Biodiversity Assessment Guidelines in Pastoral Systems in Uruguay
After the publication of the “long shadow of cattle” report, ruminant production systems have received great pressure for their contributions in greenhouse gases (GHG). However, the environmental effects of human activities are much broader than GHG production and in some cases, there are positive contributions. In order to broaden the environmental perspective and with the encouragement of governments, the private sector and NGOs, LEAP-FAO has developed environmental assessment guidelines for the world\u27s livestock production systems. This paper presents a road-testing of the Biodiversity Assessment Guideline at farm scale for six case studies in pastoral livestock systems in Uruguay. The producers involved correspond to farmers with a mixed livestock system (cows and sheep) with a full cycle and areas ranging between 2000 and 5000 hectares. Three of the farms have production based 100% on natural grasslands, while the other three had 30% of their area with sown pastures. The application of the guide at local level implies the use of the system of pressure, state and response indicators (PSR). The recommendation of the guide in its public review version requires a minimum set of 24 indicators, which can also be divided into several measurable variables. The results obtained in this study showed that the complete set is a reliable tool to evaluate the functioning of the systems in terms of their contribution to biodiversity conservation. However, some are more sensitive than others to evaluate changes depending on the scale. For example, the change in land use due to planting of forage crops clearly affects birds and arthropods such as spiders; though, due to scale of habitat use is less clear the global effect in bird population. The state indicators related to richness and diversity of species from different taxonomic groups is very relevant but result the more expensive issue in the assessment. Global indicators as the Ecosystem Integrity Index (EII) show a consistent effect of intensification but the connectivity in the actual percentages of natural grassland substitution is still good
Privacy-enhancing distributed protocol for data aggregation based on blockchain and homomorphic encryption
The recent increase in reported incidents of security breaches compromising users' privacy call into question the current centralized model in which third-parties collect and control massive amounts of personal data. Blockchain has demonstrated that trusted and auditable computing is possible using a decentralized network of peers accompanied by a public ledger. Furthermore, Homomorphic Encryption (HE) guarantees confidentiality not only on the computation but also on the transmission, and storage processes. The synergy between Blockchain and HE is rapidly increasing in the computing environment.
This research proposes a privacy-enhancing distributed and secure protocol for data aggregation backboned by Blockchain and HE technologies. Blockchain acts as a distributed ledger which facilitates efficient data aggregation through a Smart Contract. On the top, HE will be used for data encryption allowing private aggregation operations. The theoretical description, potential applications, a suggested implementation and a performance analysis are presented to validate the proposed solution.This work has been partially supported by the Basque Country Government under the ELKARTEK program, project TRUSTIND (KK- 2020/00054). It has also been partially supported by the H2020 TERMINET project (GA 957406)
Chapter Blockchain Applications in Cybersecurity
Blockchain has been widely known thanks to Bitcoin and the cryptocurrencies. In this chapter, we analyze different aspects that relate to the application of blockchain with techniques commonly used in the field of cybersecurity. Beginning by introducing the use of blockchain technology as a secure infrastructure, the document delves into how blockchain can be useful to achieve several security requirements, common to most applications. The document has been focused on some specific cybersecurity disciplines to maintain simplicity: backup and recovery, threat intelligence and content delivery networks. As illustrated, some projects and initiatives are in the process of joining these two fields to provide solutions to existing problems
Blockchain Applications in Cybersecurity
Blockchain has been widely known thanks to Bitcoin and the cryptocurrencies. In this chapter, we analyze different aspects that relate to the application of blockchain with techniques commonly used in the field of cybersecurity. Beginning by introducing the use of blockchain technology as a secure infrastructure, the document delves into how blockchain can be useful to achieve several security requirements, common to most applications. The document has been focused on some specific cybersecurity disciplines to maintain simplicity: backup and recovery, threat intelligence and content delivery networks. As illustrated, some projects and initiatives are in the process of joining these two fields to provide solutions to existing problems
Toxicidad aguda de la plata sobre Cnesterodon decemmaculatus (Pisces: Poeciliidae) en un río con características extremas de calidad de agua
A 96 h acute silver toxicity test was performed in order to determine silver toxicity (LC ) to a local fsh species (Cnester- 50 odon decemmaculatus) in a river with extreme water-quality characteristics (Pilcomayo River, South America) and evaluate a cross-fsh-species extrapolation of the Biotic Ligand Model. The dissolved silver concentrations tested were 0.095, 0.148, 0.175 calculated for C. decemmaculatus was 0.14 mg L and 0.285 mg Ag L . The 96 h Ag LC (0.18 - 0.10) and the value predicted −1 −1 50 by BLM for Pimephales promelas was 0.051 mg Ag L . Test water elevated hardness may have exerted some protective effect. −1 High mean water pH may have exerted a major protective effect by reducing silver free ion form and causing silver precipitation. The mortality pattern observed in this toxicity test may lend some support to a relationship between gill silver accumulation and mortality. A cross-fsh-species extrapolation of Ag BLM for P. promelas was not valid in Pilcomayo River water and experimental conditions of this toxicity test. Con el objeto de determinar la toxicidad de la plata en un pez nativo (Cnesterodon decemmaculatus), se llevó a cabo un ensayo estático de toxicidad aguda a 96 horas en un agua natural con características de calidad de agua, extremas (río Pilcomayo,
Sudamérica). Asimismo, se evaluó una posible extrapolación inter-especie del Modelo del Ligando Biótico en el agua experimental. La concentración inicial de plata en solución en los distintos tratamientos fue de 0,095; 0,148; 0,175 y 0,285 mg Ag
L−1. La CL50 a las 96 horas calculada para C. decemmaculatus fue de 0,14 (0.18 - 0.10) mg Ag L−1 y el valor predicho por el BLM para Pimephales promelas fue de 0,051 mg Ag L−1. La elevada dureza del agua experimental pudo haber tenido algún efecto protector frente a la toxicidad de la plata. El valor medio de pH del ensayo fue elevado y posiblemente tuvo un gran efecto protector por reducción de la forma iónica libre y precipitación del metal. El patrón de mortalidad observado en este ensayo de toxicidad apoyaría la relación causa-efecto entre acumulación de plata en las branquias y mortalidad. La extrapolación inter-especie del BLM para P. promelas no resultó válida en el agua del río Pilcomayo y en las condiciones experimentales de este ensayo.Fil: Casares, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales; Argentina;Fil: de Cabo, Laura Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales; Argentina;Fil: Seoane, Rafael Santiago. Ministerio de Planificación Federal, Inversión Pública y Servicios. Secretaria de Obras Publicas. Subsecretaria de Recursos Hídricos. Instituto Nacional del Agua y del Ambiente (Ezeiza); Argentina; Universidad de Buenos Aires. Facultad de Ingeniería; Argentina;Fil: Natale, Oscar. Ministerio de Planificación Federal, Inversión Pública y Servicios. Secretaria de Obras Publicas. Subsecretaria de Recursos Hídricos. Instituto Nacional del Agua y del Ambiente (Ezeiza); Argentina
Toxicidad aguda de la plata sobre Cnesterodon decemmaculatus (Pisces: Poeciliidae)
A 96 h acute silver toxicity test was performed in order to determine silver toxicity (LC50) to a local fish species (Cnesterodon decemmaculatus) in a river with extreme water-quality characteristics (Pilcomayo River, South America) and evaluate a cross-fish-species extrapolation of the Biotic Ligand Model. The dissolved silver concentrations tested were 0.095, 0.148, 0.175 and 0.285 mg Ag L-1. The 96 h Ag LC50 calculated for C. decemmaculatus was 0.14 mg L-1 (0.18 - 0.10) and the value predicted by BLM for Pimephales promelas was 0.051 mg Ag L-1. Test water elevated hardness may have exerted some protective effect. High mean water pH may have exerted a major protective effect by reducing silver free ion form and causing silver precipitation. The mortality pattern observed in this toxicity test may lend some support to a relationship between gill silver accumulation and mortality. A cross-fish-species extrapolation of Ag BLM for P. promelas was not valid in Pilcomayo River water and experimental conditions of this toxicity test.Con el objeto de determinar la toxicidad de la plata en un pez nativo (Cnesterodon decemmaculatus), se llevó a cabo un ensayo estático de toxicidad aguda a 96 horas en un agua natural con características de calidad de agua, extremas (río Pilcomayo, Sudamérica). Asimismo, se evaluó una posible extrapolación inter-especie del Modelo del Ligando Biótico en el agua experimental. La concentración inicial de plata en solución en los distintos tratamientos fue de 0,095; 0,148; 0,175 y 0,285 mg Ag L -1 . La CL50 a las 96 horas calculada para C. decemmaculatus fue de 0,14 (0.18 - 0.10) mg Ag L-1 y el valor predicho por el BLM para Pimephales promelas fue de 0,051 mg Ag L-1. La elevada dureza del agua experimental pudo haber tenido algún efecto protector frente a la toxicidad de la plata. El valor medio de pH del ensayo fue elevado y posiblemente tuvo un gran efecto protector por reducción de la forma iónica libre y precipitación del metal. El patrón de mortalidad observado en este ensayo de toxicidad apoyaría la relación causa-efecto entre acumulación de plata en las branquias y mortalidad. La extrapolación inter-especie del BLM para P. promelas no resultó válida en el agua del río Pilcomayo y en las condiciones experimentales de este ensayo.Fil: Casares, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales; ArgentinaFil: de Cabo, Laura Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales; ArgentinaFil: Seoane, Rafael Santiago. Ministerio de Planificación Federal, Inversión Pública y Servicios. Secretaria de Obras Publicas. Subsecretaria de Recursos Hídricos. Instituto Nacional del Agua y del Ambiente (Ezeiza); Argentina. Universidad de Buenos Aires. Facultad de Ingeniería; ArgentinaFil: Natale, Oscar. Ministerio de Planificación Federal, Inversión Pública y Servicios. Secretaria de Obras Publicas. Subsecretaria de Recursos Hídricos. Instituto Nacional del Agua y del Ambiente (Ezeiza); Argentin
La industria petroquímica
La industria petroquímica es un sector de I la industria química que utiliza derivados del petróleo y gas natural como materias primas. Esta definición es sumamente simple y no da lugar a confusiones, pero para ilustrar el campo que corresponde a este sector industrial, en el cuadro N° 1 se indica una clasificación de los principales productos de las industrias petrolera y petroquímica. En la columna A se ubican los productos naturales (petróleo crudo y gas natural) a partir de los cuales se obtiene una serie de derivados utilizados como combustibles, lubricantes, solventes, etc.; parte de los cuales son utilizados como materias primas para la industria petroquímica (columna B). A partir de ellos se obtienen los productos petroquímicos básicos (columna C ). Estos a su vez se utilizan para la elaboración de productos petroquímicos intermedios (columna D ), con los cuales se pueden obtener los productos petroquímieos finales (columna E ): agroquímicos (fertilizantes y plaguicidas), plásticos, fibras sintéticas, cauchos sintéticos, detergentes, etc.Universidad Nacional de La Plat
Removal of Acid Blue 80 from aqueous solutions using chitosan-based beads modified with choline chloride: urea Deep Eutectic Solvent and FeO
An alternative chitosan-based adsorbent modified by impregnation with deep eutectic solvent (DES) choline-chloride:urea at a molar ratio 1:2 proved efficient removal of the anthraquinone dye Acid Blue 80 (AB80) from aqueous solutions, and offered enhanced adsorption capacity compared to the starting materials. The adsorption was mainly affected by initial AB80 concentration, adsorbent dosage, contact time, and slightly influenced by temperature (25–45 °C), and pH (3.5–10). The pseudo-second-order kinetic model fitted the experimental data, and pseudo-first order model fitted as well at the highest AB80 concentration, 250 mg/L. The experimental data agreed with the Langmuir isotherm model, with a maximum adsorption capacity of 61.64 mg/g at 35 °C. The process was exothermic above 100 mg/L of dye and spontaneous up to 200 mg/L (T < 35 °C). The adsorbent could be reused without further treatment at least 5 times providing ≥40% removal, whereas the dye could be efficiently recovered by NaOH desorption. Electrostatic interactions as well as physisorption could explain the adsorption behaviorAgencia Estatal de Investigación | Ref. PID2019-107728RB-I00Xunta de Galicia | Ref. ED431B 2020/08Financiado para publicación en acceso aberto: Universidade de Vigo/CISU
Design of a fatigue test bench in rotary flexion to evaluate the behavior to cyclical loads
The development of this article shows the process of design, construction and start-up of a fatigue machine in rotary flexion. Fatigue is a subject of considerable relevance and requires adequate equipment for its study, therefore it is sought to contribute to educational and research growth through the development of a functional fatigue machine and where a variety of materials can be studied. The main results were the development of a machine that can carry out a totally inverted stress of 977 Mpa, therefore it can arrive to study steels of high resistance. This machine follows the standards of the normative ASTM E-466 regarding the dimensions of the test specimen. The design of the machine is divided into 3 systems, mechanical system, electrical system and electronic system. When joining these systems obtained a functional and autonomous machine where can make serious and reliable investigations.The development of this article shows the process of design, construction and start-up of a fatigue machine in rotary flexion. Fatigue is a subject of considerable relevance and requires adequate equipment for its study, therefore it is sought to contribute to educational and research growth through the development of a functional fatigue machine and where a variety of materials can be studied. The main results were the development of a machine that can carry out a totally inverted stress of 977 Mpa, therefore it can arrive to study steels of high resistance. This machine follows the standards of the normative ASTM E-466 regarding the dimensions of the test specimen. The design of the machine is divided into 3 systems, mechanical system, electrical system and electronic system. When joining these systems obtained a functional and autonomous machine where can make serious and reliable investigations
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