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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

SeedCup, vasos de fécula de maíz que pueden ser sembrados / SeedCup, cornstarch cups that can be plant

Campos Palacios, Marco Alejandro, Icochea Rodriguez, Mariana Lizette, Ortega Buleje, Renzo Andres, Quiroz Sanchez, Flavio Augusto, Sernaqué Vega, Cecilia Andrea 01 July 2019 (has links)
El presente proyecto sobre vasos de fécula de maíz con semillas de hortalizas en su base para su sembrado nos muestra la viabilidad de su ejecución, en base a la investigación en la zona 7 de Lima Metropolitana de los NSE “A” y “B” de edades 18 a 45 años, permitió detectar un mercado insatisfecho debido a la poca accesibilidad de vasos eco-amigables en el mercado peruano. En la actualidad, la falta de productos eco-amigables genera disconformidad en consumidores que buscan productos que no contaminen el medio ambiente. Debido a la falta de oferta, el público se ve en la necesidad de adquirir productos con materiales contaminantes. El proyecto contempla la venta de vasos de fécula de maíz con semillas de hortalizas en la base para hombres y mujeres de la zona 7 de Lima Metropolitana de los NSE “A” y “B” de edades 18 a 45 años, a través de una tienda física, virtual (Facebook) y ferias ecológicas, donde brindaremos una atención de primer nivel y explicaremos los beneficios y la manera de cómo sembrar nuestro producto. SeedCup se distinguirá por su atención al cliente y su modelo de negocio innovador, así como su Responsabilidad Social Empresarial, que se encarga de ayudar a una organización de mujeres en la capital. Para poder realizar este proyecto necesitaremos una inversión inicial de S/381,517, financiado en su totalidad por recursos propios, que estimamos recuperar a los 3 años. / The present project about cornstarch cups with vegetable seeds at its base for sowing show us the feasibility of its execution, based on the research in Zone 7 of Metropolitan Lima of the socioeconomic level “A” and “B” of ages 18 to 45, allowed to detect an unsatisfied market due to the lack of accessibility of eco-friendly cups in the Peruvian market. At present, the lack of eco-friendly products creates disagreement in consumers looking for products that do not pollute the environment. Due to the lack of supply, the public is in need of acquiring products with polluting materials. The project contemplates the sale of cornstarch cups with vegetable seeds at the base for men and women of Zone 7 of Metropolitan Lima of the socioeconomic level “A” and “B” aged 18 to 45 years, through a physical, virtual store (Facebook) and ecological fairs, where we will provide first class attention and explain the benefits and the way of planting our product. SeedCup will be distinguished by its customer service and its innovative business model, as well as its Corporate Social Responsibility, which is responsible for helping a women's organization in the capital. In order to carry out this project, we will need an initial investment of S / 381,517, financed entirely by our own resources, which we estimate to recover after 3 years. / Trabajo de investigación
242

SALUFFA – esponjas para el cuidado de la piel

Anaya Medina, Fiorella, Coral Sartori, Pamela Sandy, Cruzado Hernandez, Bryan Kevin, Pizarro Sayán, Fiorela Milagros, Vivas Cubas, Diana María 02 February 2021 (has links)
Nuestro proyecto se genera a partir de una preocupación que afecta a muchas personas en el mundo, el uso de plásticos para la elaboración de artículos de cuidado personal y la escasa ayuda a las organizaciones comunitarias a partir de un modelo de negocio. Es por ello, que la idea de negocio se genera a partir de esas dos necesidades. Este proyecto se divide en dos etapas fundamentales; la validación del problema y la solución propuesta. Hoy en día las personas no tienen conciencia en el impacto del uso de artículos de cuidado personal que son hechos a base de plásticos, ya que no cuentan con un conocimiento de los productos biodegradables que existen en el mercado. Sin embargo, cuando se deciden a comprar productos biodegradables no suelen ser constantes en sus compras; ya que no saben del todo sus beneficios que tienen y el valor agregado que podría tener su contribución mediante la compra. Es aquí donde Saluffa decide apostar por las esponjas biodegradables que son producidas en la región de Ancash por la Organización Matto Grosso para presentarlas en un kit de esponjas que cuentan con tres presentaciones y ser comercializadas en Lima Metropolitana. En la primera etapa, se realizaron entrevistas a nuestro público objetivo y expertos con la finalidad de obtener información relevante para nuestro problema. En la segunda etapa, se realizó nuestro modelo de negocio para determinar si es que nuestro proyecto resultaría viable. Nuestro diferencial de producto son los múltiples beneficios que tiene y el valor agregado que es la contribución monetaria a la OMG, mediante el contrato de exclusividad para la comercialización de las luffas. Las proyecciones indican que bajo una tasa de descuento de %, lograremos un VAN de S/.41,162 soles con una tasa interna de retorno (TIR) de % en un periodo de recupero de la inversión de años por lo cual nuestro proyecto sería viable en cuanto a inversión. / Our project is generated from a concern that affects many people in the world, the use of plastic to produce personal care items and a little help to community organizations based on a business model. That is why the business idea is generated from these two needs. This project is divided into two fundamental stages: the validation of the problem and the proposed solution. Today people are not aware of the impact of the use of personal care items that are made from plastic, since they do not have a knowledge of the biodegradable products that exist in the market. However, when they decide to buy biodegradable products, they are not usually constant in their buying; since they do not fully know their benefits and the added value that their contribution and could have through the purchase. It is here where Saluffa decides to invest in the biodegradable sponges that are produced in the Ancash region by Matto Grosso Organization to present them in a sponge kit that have three presentations and be marketed in modern Lima. In the first stage, interviews were conducted with our target audience and expert to obtain relevant information for our problem. In the first stage, interviews were conducted with our target audience and expert to obtain relevant information for our problem. In the second stage, our business model was carried out to determine if our project would be viable. Our product differential is the multiple benefits it has and the added value that is the monetary contribution to the OMG, through the exclusive contract for the commercialization of the luffas. The projections indicate that under a discount rate of %, we will achieve a VAN of S/.41,162 soles with an internal rate of return (IRR) of % in a period of recovery of investment of years for which our project would be viable as investment. / Trabajo de investigación
243

Duty-to-Inform, Discrimination, and Septic-System Issues

Sikora, Vincent A. 01 November 2003 (has links)
No description available.
244

Análisis estático y frecuencial en el chasis de un camión de 8T utilizando PRFV para reducir el consumo de combustible

Cosmopolis Pol, Grecia January 2023 (has links)
Es muy probable que hoy en día cualquier objeto que esté a nuestro alrededor haya estado en algún momento de su vida en el interior de un camión de carga, ya que estos son indispensables para el transporte de cualquier tipo de elemento. Desde alimentos, prendas de vestir, muebles, materiales de construcción, hasta maquinaria pesada es transportada por estos vehículos pesados. Por este motivo son considerados parte esencial de la economía mundial, pero al ser sometidos a grandes cargas, estos producen una gran contaminación ambiental, debido al combustible que utilizan. La presente investigación tuvo como objetivo disminuir el consumo de combustible del camión mediante la implementación del material compuesto PRFV (Plástico Reforzado con Fibra de Vidrio) como material principal en el chasis en vez de los aceros comúnmente utilizados en su manufactura. La metodología utilizada inició con el dimensionamiento del chasis y se evaluó las propiedades mecánicas del PRFV, para después proceder a la simulación estáticofrecuencial del chasis; los resultados de la simulación fueron comparados con respecto al acero AISI 4135 para finalmente proceder con el cálculo del consumo de combustible del camión con el nuevo material. Con el cambio de material se logró disminuir el peso del camión en 536 Kg, generando así un ahorro de 438.4 L en el uso de combustible, lo cual da un ahorro económico de S/1995.31. / Its most likely nowadays that any object around us has been at some moment in its life inside a cargo truck, since these are indispensable for the transportation of any type of element. From food, clothing, furniture, construction materials, to heavy machinery is transported by these heavy vehicles. For this reason, they are considered an essential part of the world economy, but when subjected to heavy loads, they produce a great amount of environmental pollution, due to the fuel they use. The objective of this research is to reduce the fuel consumption of the truck by implementing GFRP (Glass Fiber Reinforced Plastic) as the main material in the chassisinstead of the Steel commo nly used in its manufacture. The methodology used started with the sizing of the chassis and the mechanical properties of the GFRP were evaluated and then proceeded to the static-frequency simulation of the chassis, the results of the simulations were compared with the Steel alloy AISI 4135, to finally proceed to calculate the fuel consumption of the truck with the new material. By changing the material, the weight of the truck was reduced by 536Kg, which generate a saving of 438.4 L in fuel consumption, resulting in a economic saving of S/.1995,31.
245

Повышение международной конкурентоспособности промышленного предприятия Российской Федерации : магистерская диссертация / Increasing the international competitiveness of an industrial enterprise of the Russian Federation

Шулишов, Д. И., Shulishov, D. I. January 2021 (has links)
В работе рассмотрены теоретические аспекты международной конкурентоспособности промышленного предприятия; проанализирована деятельность ПАО «ГМК «Норильский никель» в контексте его международной конкурентоспособности; разработаны предложения по повышению международной конкурентоспособности ПАО «ГМК «Норильский никель». / The paper considers the theoretical aspects of the international competitiveness of an industrial enterprise; analyzed the activities of PJSC MMC Norilsk Nickel in the context of its international competitiveness; proposals were developed to improve the international competitiveness of PJSC MMC Norilsk Nickel.
246

Protection of Public and Worker Safety by Understanding Hazardous Chemical Air and Exposure Risks during Plastic Cured-In-Place-Pipe Manufacture and Use

Yoorae Noh (13113138) 18 July 2022 (has links)
<p>  </p> <p>Globally, communities are embracing the cured-in-place-pipe (CIPP) process due to the need to address damaged buried water and sewer pipes. CIPP involves the chemical manufacture of a new plastic pipe inside an existing buried water and sewer pipe, without the need for excavation. The process is popular because it can be 80% less costly than alternative methods and construction workers can be present for hours to not days to weeks. However, as CIPP use has grown, so have the number of hazardous material (HAZMAT) incidents caused by using this practice. Evacuations of daycare centers, schools, homes, healthcare, institutional, and other buildings have been caused. In some cases, chemical exposure victims have required medical assistance and hospital admission. For decades, organizations within the CIPP industry and municipalities have encouraged chemical waste discharge into ambient air, resulting in preventable exposures. Recent work has indicated tons of volatile organic compounds (VOC) may be released during a single CIPP project into the air. Chemicals released include hazardous air pollutants (HAP), carcinogens (CAR), endocrine disrupting chemicals (EDR), and other compounds with little toxicological information. While polymer composites have been manufactured for other applications for more than 50 years, little information exists about what chemicals and materials are used to manufacture CIPPs. As CIPP use has grown along with the number of bystander chemical exposures, concerns about the type, magnitude, and toxicity of chemical emissions from CIPP projects have markedly increased. To reduce the potential for human harm and environmental degradation, a better understanding of CIPP composite chemistry and manufacturing is needed. This dissertation aimed to elucidate the processes that control the composition of waste generated during plastic CIPP manufacture and ascertain how to modify the manufacturing practice to minimize impacts on composite integrity and emission toxicity. </p> <p>Chapter 1 focused on indoor VOC exposure simulation and styrene contamination/ decontamination to evaluate the risk of occupant exposure during CIPP installation. Styrene is a common monomer used in many CIPP resins and can be discharged into the air at CIPP worksites. A review of prior incidents revealed that CIPP waste (liquid, organic chemicals, etc.) could enter nearby buildings through multiple routes including windows, doors, or heating, ventilation, and air conditioning outdoor air intakes. When CIPP is manufactured inside a sanitary sewer pipe, waste can enter buildings through sewer laterals of nearby buildings and through foundation cracks. Study results showed that plumbing seal backflows in bathrooms caused by sewer repair work are hydraulically possible: the minimum pressure required to displace water in the plumbing trap was estimated to be 0.995 kPa and 8.85 kPa for a sink and toilet, separately. These pressures are much lower than those applied by the contractor during the sewer lining (up to 193.05 kPa). Based on the indoor exposure events, the dissipation potential of vapors, as well as the hydraulic calculations, indoor air chemical contamination and decontamination profiles were also examined. A mass balance model of chemical vapor dispersion was developed. Modeling results revealed that bathroom exhaust fan operation during a CIPP project can increase the indoor styrene concentration by enhancing the inflow of styrene-containing air from the sink and toilet. However, the styrene concentration decreased as air leaked across the bathroom door due to reduced suction in the plumbing. Based on incident reviews, chemical magnitudes, and modeling results it was concluded that CIPP waste discharge should be treated as hazardous material discharge, because of its threat to human health. Actions are needed to reduce waste generation and contain the waste, so it does not leave the worksite. Chapter 2 aimed to determine the manufacturing conditions that most influence chemical residual left in the thermally manufactured CIPP. Bench-scale testing of multiple styrene- and non-styrene composites revealed the manufacturing conditions (curing time, temperature, initiator loading) necessary to produce a high integrity composite while minimizing chemical residual and air emissions. Even though the VOC loading of the non-styrene resin (4 wt.%) was much less than that of styrene resin (39 wt.%), the non-styrene resin did contain HAP, EDR, CAR compounds including ethylbenzene, 2-ethylhexanoic acid, methacrylic acid, styrene, toluene, and <em>m</em>-xylene. Study results also revealed that by changing initiator loading a drastic reduction in the amount of styrene (-42 wt.%) and styrene oxide (-33 wt.%) residual left in the newly manufactured composite was achieved. Discoveries prompted a new hypothesis that this decreased residual also prompted a decreased amount of VOCs emitted into the air. The explanation is that this occurs because that a greater amount of the monomer styrene was incorporated into the resin during polymerization and not permitted to enter the air. Despite decades of polymer composite use, this study provides a new fundamental understanding of composite chemicals and techniques for reducing air pollutant emissions during plastic composite manufacture. In Chapter 3, the complexity of organic vapor chemicals found in the air during thermal heating of CIPP composites was explored and quantified. The emission rate of a popular monomer, styrene, was quantified from the materials before, during, and after composite manufacture. Scaling up bench-scale results, 1.9 to 14 US tons and 0.18 to 1.35 US tons of VOCs (0.05 to 0.36 US tons and 0.001 to 0.007 US tons of styrene) were estimated to be emitted during curing of styrene- and non-styrene CIPPs (i.e., typically 1-3 m of diameter pipes). By modifying standard air sampling methods, previously undetectable chemicals associated with CIPP manufacture were found in the styrene-laden air. These include acetophenone, benzaldehyde, phenol, and 1,3,5-trimethylbenzene. Results have immediate relevance to improved air monitoring for public and worker safety. Further, results can be used to examine the cumulative health and environmental risks of the CIPP pollutant mixtures. Chapter 4 focused on identifying CIPP technology/knowledge gaps and feedback from health officials from multiple state and federal agencies. Through this study, a public health workgroup was assembled to include disciplinary experts and 13 federal, state, and city health agencies and public health associations. Building on dialogue with U.S. health officials, the state of knowledge pertaining to CIPP chemical exposures, mitigation, and response actions was reviewed. Topics included 1) CIPP manufacturing process and waste; 2) sewers and buildings; 3) chemical exposure and health; 4) chemical risk assessment; 5) risk communication. This study helped establish relationships among federal, state, and city officials to improve public health response. Additionally, a primer for CIPP chemical fate and transport, as well as assisting in identifying and prioritizing public health information needs was developed. Identification and prioritization of current public health knowledge gaps and proposed practices for reducing exposures to the public and workers were reported. CIPP-related bench and research results throughout the dissertation can serve as an important basis for environmental policy and public health guidelines on the prevention and mitigation aspects of environmental and human health impacts resulting from CIPP manufacturing practices.</p>
247

Estudo das alterações no desenvolvimento, no comportamento e na bioquímica cerebral de ratos machos adultos expostos à poluição atmosférica ambiental durante a fase intra-uterina e o período de lactação / Study of the alterations in the development, behavior and cerebral biochemistry of male rats exposed to the environmental atmospheric pollution in the intra-uterine phase

Zanchi, Ana Claudia Tedesco 16 April 2010 (has links)
Estudos experimentais feitos em nosso laboratório comprovaram que a inalação de material particulado proveniente da queima de combustíveis fósseis utilizados em siderurgia pelos ratos adultos diminuiu a atividade motora dos animais no campo aberto. Além disso, provamos que os ratos habituaram ao ambiente desse teste, o que significa que a inalação desse tipo de material não provocou variação em termos de aprendizado simples. Uma das causas da alteração no comportamento em relação à motricidade seria o estresse oxidativo causado pelo material particulado no estriado e cerebelo desses animais. Entretanto, em nossa cidade não existem estudos que demonstrem a estreita associação entre inalação de poluentes, estresse oxidativo e alterações comportamentais. Baseados nos nossos trabalhos anteriores e na literatura, nosso objetivo foi investigar se a poluição atmosférica a nível ambiental durante as fases pré e pós-natal alteraria a memória discriminativa de curta-duração e a memória espacial. Além disso, avaliamos o papel do estresse oxidativo como o mecanismo propulsor dessas mudanças de comportamento. Para tal, ratas prenhas foram expostas ao ar filtrado e ao ar não filtrado durante os 21 dias de gestação. Ao final do período de amamentação, os machos foram separados e subdividos em 4 grupos experimentais (n=24): 1) Filtrado: nasceu e viveu em ambiente cujo ar era filtrado, 2) NFF: nasceu em ambiente cujo ar era não filtrado e viveu a partir do 21o dia do pós-natal no ambiente com ar filtrado, 3) FNF: nasceu sob ar filtrado e viveu a partir do 21o dia do pós-natal sob ar não filtrado, 4)NF: nasceu e viveu em ambiente cujo ar era não filtrado. Os animais ficaram expostos a poluição por 150 dias. Os animais foram divididos em 3 lotes: lote 1: n=6 animais por grupo; após anestesia profunda, os animais foram perfundidos com soro fisiológico seguido de paraformaldeído 4%, o encéfalo foi retirado e dissecado em córtex, hipocampo e estriado para análises histológicas por técnicas estereológicas; lote 2: n=12 ratos por grupo; aplicação dos testes comportamentais; um dia após os testes, esses animais foram eutanasiados por decapitação, o encéfalo retirado e dissecado da mesma forma citada anteriormente para análise de estresse oxidativo; lote 3: n=6 animais por grupo; os animais foram decapitados e o sangue troncular coletado para análises de elementos traço tóxicos e essenciais no sangue total. O córtex apresentou lipoperoxidação no grupo NF quando comparado aos outros grupos, assim como uma alta concentração de Cd no sangue. O grupo NFF apresentou uma maior concentração de Cu, Se e Zn no sangue em relação aos demais. Em relação à memória discriminativa de curta-duração, houve uma diminuição no grupo NF em relação aos demais grupos. No hipocampo e estriado, foi observado aumento da lipoperoxidação nos grupos FNF e NF, respectivamente, quando comparado aos outros grupos. Quanto à memória espacial, não houve diferença estatisticamente significativa entre os grupos. Primeiramente, como pudemos observar, o cada estrutura encefálica apresenta uma resposta ao estresse oxidativo. O córtex do grupo NF apresentou aumento de lipoperoxidação. Como se sabe, o Cd é feto tóxico e passa via transplacentária adsorvido ao material particulado inalado pela mãe. No caso do grupo NF, o Cd possivelmente deslocou o Zn do sítio ativo da enzima CuZn superóxido dismutase formando forma inativada da mesma. O Cd, também, forma conjugado com duas moléculas de glutationa reduzida a fim de ser excretado pela bile. Isso reduz a sua capacidade antioxidante. Esse elemento traço desloca o Fe e o Cu dos sítios ativos das suas proteínas de armazenamento, a ferritina e a ceruplasmina, respectivamente. Esses dois elementos ficam livres para catalisar a reação de Fenton cujo produto é o radical hidroxil, extremamente tóxico para o organismo. O grupo NF apresentou uma diminuição na capacidade de discriminar dois objetos diferentes. Provavelmente, o Cd agiu de forma indireta diminuindo a capacidade antioxidante da CuZn superóxido dismutase e da glutationa, além de liberar Fe e Cu e aumentar a produção de radical hidroxil. O aumento da lipoperoxidação causado pelo Cd pode ser o mecanismo responsável pela perda desse tipo de memória. Entretanto, o grupo NFF, cuja exposição à poluição foi na fase pré-natal, não apresentou aumento na lipoperoxidação. Possivelmente, a alta concentração dos elementos traço essenciais, Cu, Zn e Se aumentou a atividade das enzimas CuZn superóxidodismutase e glutationa peroxidase, respectivamente, o que evitou danos oxidativos durante o período intra-uterino. O grupo FNF apresentou aumento de lipoperoxidação no hipocampo, mas não houve diferença na memória espacial testada com o labirinto de Morris modificado. Portanto, considerando todos os achados, concluímos que, possivelmente, o aumento da lipoperoxidação causado indiretamente pelo Cd pode ser um dos mecanismos responsáveis pela perda da capacidade da memória discriminativa de curta-duração. Além disso, os elementos traço essenciais exercem uma proteção via aumento das defesas antioxidantes dos animais que nasceram em ambiente poluído e, após 21 dias de vida, foram transferidos para o ambiente com o ar filtrado, o que demonstra, provavelmente, a existência de mecanismos antioxidantes de adaptação em ambientes inóspitos como forma de proteção contra o agente agressor durante o desenvolvimento do embrião. / Experimental studies done at our laboratory demonstrated that the inhalation of residual oil fly ash by the adult rats decreased motor activity of the animals in the open-field test. Additionaly, we showed that rats which inhalated residual oil fly ash preserved its habituation capacity. In this study, oxidative stress in striatum and cerebellum might be the cause of motor activity alterations. However, there were any studies about air pollution and behavioral alterations in Porto Alegre. Based on our previous works and in the literature, our objective was to investigate if the exposure to air pollution during intrauterine and lactation periods would damage the short term discriminative and spatial memories and if the mechanisms would be dependent of oxidants. For such, female pregnant rats were exposed to the filtered air and to the non filtered air during the 21 days of gestation. At the end of the breast-feeding period, the males were separate and divided in 4 experimental groups (n =24): 1) Filtered (F): - pre and post-natal exposure until adulthood in filtered air; 2) non filtered/filtered air (NFF): pre-natal period in non-filtered air until PND21 and post-natal in filtered air until adulthood; 3) filtered air/non-filtered air (FNF): pre-natal period in filtered air until PND 21 and post-natal period in non-filtered air until adulthood; 4) non filtered air (NF): pre and post-natal periods in non-filtered air.The animals were exposed the pollution for 150 days. The animals were divided in 3 lots: lot 1: n=6 animals per group; after anesthesia, the animals were perfused with saline solution following by paraformaldehyde 4%, the brain was removed and dissected in cortex, hippocampus and striatum for histological analyses by stereological techniques; lot 2: n=12 rats per group; submitted to behavioral tests; one day after the tests, those animals were euthanized by decapitation, the brain was removed and dissected in the same way mentioned previously for oxidative stress analysis; lot 3: 6 animals per group; the animals were decapitated and the troncular blood was collected to analyze the toxic and the essential trace elements. The cortex presented lipoperoxidation in NF group when compared to other groups, as well as a high concentration of Cd in the blood. The group NFF presented higher blood concentration of Cu, Se and Zn when compared to other groups. There was a decrease in the discriminative capacity in the group NF when compared to other groups. In the hippocampus and striatum, increases of lipidperoxidation were observed in the groups FNF and NF, respectively, when compared to other groups. Spatial memory of all groups was preserved. We observed the each brain structure reacts in a different way to oxidative stress. The NF cortex group presented an increased of lipidperoxidation. In this group, there was higher Cd blood concentration, which passes through placenta and it is fetotoxic. It might be possible that Cd dislocated Zn of the active site of CuZn superóxido dismutase resulting in inactive forms of this enzyme. The Cd also depletes reduced glutathione. Moreover, Cd may dislocate the Fe and Cu from its storage proteins to react with oxygen peroxide increasing the hydroxyl radical production by Fenton reaction. The group NF presented a decrease in the capacity to discriminate two different objects. Cd may act in an indirect way reducing the antioxidant capacity of CuZn superxidodismutase and of the glutathione and increasing the hydroxyl radical production. Lipoperoxidation in NF cortex caused by the Cd may be one of the mechanisms which explain the loss of discriminative capacity. However, the group NFF, whose air pollution exposure was in the pre-natal period, did not present increase of lipidperoxidation. The higher concentrations of essential trace elements (Cu, Se and Zn) may protect this group against oxidative stress. These elements are cofactor of antioxidants enzymes, superoxidodismutase and glutathione peroxidase and increased its activities during the intra-uterine exposure to air pollution. The group FNF presented lipidperoxidation increase in the hippocampus, but there was no difference in the spatial memory tested with Morris\' maze. Therefore, considering our data, we suggested that the increase of lipidperoxidation caused indirectly by Cd, which was adsorbed in particulate matter surface, may be one of the mechanisms which explain the loss of short-term discriminative memory
248

Sulfur supply as a sustainable technology for phytoextraction: its effects on cadmium uptake and detoxification in Panicum maximum Jacq. cv. Massai / Suprimento de enxofre como tecnologia sustentável para fitoextração: efeitos na absorção e detoxificação de cádmio em Panicum maximum Jacq. cv. Massai

Rabêlo, Flávio Henrique Silveira 08 February 2018 (has links)
Cadmium (Cd) concentration in the environment has increased in most recent decades, which represents a serious socio-environmental problem, since Cd is toxic to most living beings. Thus, it is important to reduce the concentration of this metal in contaminated environments, and the use of plants properly supplied with sulfur (S) can contribute to this (phytoextraction), since S is a component of metabolites involved in defense responses against stress caused by Cd. Therefore, our aim with this study was to evaluate the effect of S on i) Cd uptake kinetics, ii) root development and nutrient uptake, iii) metabolic profiling and thiol peptides synthesis, and iv) activity of antioxidant and photosynthetic system of Massai grass (Panicum maximum Jacq. cv. Massai) used for Cd phytoextraction. The studies were carried out in a greenhouse conditions using pots of 0.5 and 2.0 L for development of the study about Cd uptake kinetics (treatments represented by combinations of S: 0.1 and 1.9 mmol L-1 and Cd concentrations: 0.1 and 0.5 mmol L-1) and Cd detoxification mechanisms (treatments represented by combinations of S: 0.1, 1.9 and 3.7 mmol L-1 and Cd concentrations: 0.0, 0.1 and 0.5 mmol L-1), respectively. Pots were distributed in randomized blocks, with four replications. Plants used in Cd kinetics study were exposed to treatments for 14 days after they remained in solutions containing only S for 42 days, while plants used in Cd detoxification study were exposed to treatments for 9 days after growing in solutions containing only S for 44 days. At the end of studies, plants used were harvested and sent for analysis. Maximum uptake rate (Vmax) and Cd apoplastic influx of Massai grass exposed to highest Cd concentration was highest when the plants were supplied with highest S concentration. The root development of Massai grass was strongly inhibited when plants were exposed to 0.5 mmol L-1 Cd, but proper (1.9 mmol L-1) S supply allowed highest Cd uptake, while excessive S supply (3.7 mmol L-1) decreased iron plaques formation in the roots of plants. Lysine, cysteine, ornithine, arginine, tryptophan and histidine were accumulated in more than one tissue in plants exposed to Cd, as well as galactinol. Glutathione (GSH), phytochelatins (PCs) and their homologues were strongly induced by Cd, whereas plants supplied with 1.9 and/or 3.7 mmol L-1 S showed the highest concentrations of these peptides. Plants supplied with highest S concentration showed lowest lipid peroxidation and highest photosynthetic rate, which evidences that antioxidant system of these plants was more efficient in mitigating the damages caused by Cd. In view of these results, it is clear that Massai grass properly supplied with S shows greatest Cd tolerance, as well as phytoextraction potential / A concentração de cádmio (Cd) no ambiente aumentou em décadas recentes, o que representa sério problema sócio-ambiental, visto que o Cd é tóxico para a maioria dos seres vivos. Por isso, é importante reduzir a concentração desse metal em ambientes contaminados e o uso de plantas adequadamente supridas com enxofre (S) pode contribuir para isso (fitoextração), uma vez que o S é componente de metabólitos envolvidos no combate ao estresse causado pelo Cd. Assim, o nosso objetivo com esse estudo foi avaliar o efeito do S na i) cinética de absorção do Cd, no ii) desenvolvimento radicular e na absorção de nutrientes, no iii) perfil metabólico e síntese de compostos tiol, e iv) na atividade do sistema antioxidante e fotossintético do capim-massai (Panicum maximum Jacq. cv. Massai), utilizado para fitoextração de Cd. Os estudos foram conduzidos em casa de vegetação utilizando-se vasos de 0,5 e 2,0 L para a condução do estudo de cinética de absorção de Cd (tratamentos representados pelas combinações das doses de S de 0,1 e 1,9 mmol L-1 e Cd de 0,1 e 0,5 mmol L-1) e para o estudo dos mecanismos de detoxificação de Cd (tratamentos representados pelas combinações das doses de S de 0,1; 1,9 e 3,7 mmol L-1 e Cd de 0,0; 0,1 e 0,5 mmol L-1), respectivamente. Os vasos foram distribuídos em blocos ao acaso, com quatro repetições. As plantas utilizadas no estudo de cinética foram expostas aos tratamentos durante 14 dias após as mesmas terem permanecido em soluções contendo apenas S durante 42 dias, enquanto as plantas utilizadas no estudo de detoxificação de Cd foram expostas aos tratamentos pelo período de 9 dias após terem crescido em soluções contendo apenas S por 44 dias. Ao final dos estudos, as plantas utilizadas foram colhidas e encaminhadas para análises. A velocidade máxima de absorção (Vmax) e o influxo apoplástico de Cd do capim-massai exposto à maior dose de Cd foram maiores quando as plantas foram supridas com a maior dose de S. O desenvolvimento radicular do capim-massai foi fortemente inibido quando as plantas foram expostas à dose de Cd de 0,5 mmol L-1, mas o adequado (1,9 mmol L-1) suprimento de S permitiu maior absorção de Cd, enquanto o suprimento excessivo (3,7 mmol L-1) de S diminuiu a formação de placas de ferro nas raízes das plantas. A lisina, cisteína, ornitina, arginina, triptofano e histidina foram acumulados em mais de um tecido nas plantas expostas ao Cd, assim como o galactinol. A glutationa (GSH), as fitoquelatinas (PCs) e seus homólogos foram fortemente induzidos pelo Cd, sendo que as plantas supridas com as doses de S de 1,9 e/ou 3,7 mmol L-1 apresentaram as maiores concentrações desses peptídeos. As plantas supridas com as maiores doses de S apresentaram menor peroxidação lipídica e maior taxa fotossintética, o que demonstra que o sistema antioxidante dessas plantas foi mais eficiente na atenuação dos danos causados pelo Cd. Diante desses resultados, fica claro que o capim-massai suprido adequadamente com S apresenta maior tolerância ao Cd, assim como maior potencial de fitoextração
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Sulfur supply as a sustainable technology for phytoextraction: its effects on cadmium uptake and detoxification in Panicum maximum Jacq. cv. Massai / Suprimento de enxofre como tecnologia sustentável para fitoextração: efeitos na absorção e detoxificação de cádmio em Panicum maximum Jacq. cv. Massai

Flávio Henrique Silveira Rabêlo 08 February 2018 (has links)
Cadmium (Cd) concentration in the environment has increased in most recent decades, which represents a serious socio-environmental problem, since Cd is toxic to most living beings. Thus, it is important to reduce the concentration of this metal in contaminated environments, and the use of plants properly supplied with sulfur (S) can contribute to this (phytoextraction), since S is a component of metabolites involved in defense responses against stress caused by Cd. Therefore, our aim with this study was to evaluate the effect of S on i) Cd uptake kinetics, ii) root development and nutrient uptake, iii) metabolic profiling and thiol peptides synthesis, and iv) activity of antioxidant and photosynthetic system of Massai grass (Panicum maximum Jacq. cv. Massai) used for Cd phytoextraction. The studies were carried out in a greenhouse conditions using pots of 0.5 and 2.0 L for development of the study about Cd uptake kinetics (treatments represented by combinations of S: 0.1 and 1.9 mmol L-1 and Cd concentrations: 0.1 and 0.5 mmol L-1) and Cd detoxification mechanisms (treatments represented by combinations of S: 0.1, 1.9 and 3.7 mmol L-1 and Cd concentrations: 0.0, 0.1 and 0.5 mmol L-1), respectively. Pots were distributed in randomized blocks, with four replications. Plants used in Cd kinetics study were exposed to treatments for 14 days after they remained in solutions containing only S for 42 days, while plants used in Cd detoxification study were exposed to treatments for 9 days after growing in solutions containing only S for 44 days. At the end of studies, plants used were harvested and sent for analysis. Maximum uptake rate (Vmax) and Cd apoplastic influx of Massai grass exposed to highest Cd concentration was highest when the plants were supplied with highest S concentration. The root development of Massai grass was strongly inhibited when plants were exposed to 0.5 mmol L-1 Cd, but proper (1.9 mmol L-1) S supply allowed highest Cd uptake, while excessive S supply (3.7 mmol L-1) decreased iron plaques formation in the roots of plants. Lysine, cysteine, ornithine, arginine, tryptophan and histidine were accumulated in more than one tissue in plants exposed to Cd, as well as galactinol. Glutathione (GSH), phytochelatins (PCs) and their homologues were strongly induced by Cd, whereas plants supplied with 1.9 and/or 3.7 mmol L-1 S showed the highest concentrations of these peptides. Plants supplied with highest S concentration showed lowest lipid peroxidation and highest photosynthetic rate, which evidences that antioxidant system of these plants was more efficient in mitigating the damages caused by Cd. In view of these results, it is clear that Massai grass properly supplied with S shows greatest Cd tolerance, as well as phytoextraction potential / A concentração de cádmio (Cd) no ambiente aumentou em décadas recentes, o que representa sério problema sócio-ambiental, visto que o Cd é tóxico para a maioria dos seres vivos. Por isso, é importante reduzir a concentração desse metal em ambientes contaminados e o uso de plantas adequadamente supridas com enxofre (S) pode contribuir para isso (fitoextração), uma vez que o S é componente de metabólitos envolvidos no combate ao estresse causado pelo Cd. Assim, o nosso objetivo com esse estudo foi avaliar o efeito do S na i) cinética de absorção do Cd, no ii) desenvolvimento radicular e na absorção de nutrientes, no iii) perfil metabólico e síntese de compostos tiol, e iv) na atividade do sistema antioxidante e fotossintético do capim-massai (Panicum maximum Jacq. cv. Massai), utilizado para fitoextração de Cd. Os estudos foram conduzidos em casa de vegetação utilizando-se vasos de 0,5 e 2,0 L para a condução do estudo de cinética de absorção de Cd (tratamentos representados pelas combinações das doses de S de 0,1 e 1,9 mmol L-1 e Cd de 0,1 e 0,5 mmol L-1) e para o estudo dos mecanismos de detoxificação de Cd (tratamentos representados pelas combinações das doses de S de 0,1; 1,9 e 3,7 mmol L-1 e Cd de 0,0; 0,1 e 0,5 mmol L-1), respectivamente. Os vasos foram distribuídos em blocos ao acaso, com quatro repetições. As plantas utilizadas no estudo de cinética foram expostas aos tratamentos durante 14 dias após as mesmas terem permanecido em soluções contendo apenas S durante 42 dias, enquanto as plantas utilizadas no estudo de detoxificação de Cd foram expostas aos tratamentos pelo período de 9 dias após terem crescido em soluções contendo apenas S por 44 dias. Ao final dos estudos, as plantas utilizadas foram colhidas e encaminhadas para análises. A velocidade máxima de absorção (Vmax) e o influxo apoplástico de Cd do capim-massai exposto à maior dose de Cd foram maiores quando as plantas foram supridas com a maior dose de S. O desenvolvimento radicular do capim-massai foi fortemente inibido quando as plantas foram expostas à dose de Cd de 0,5 mmol L-1, mas o adequado (1,9 mmol L-1) suprimento de S permitiu maior absorção de Cd, enquanto o suprimento excessivo (3,7 mmol L-1) de S diminuiu a formação de placas de ferro nas raízes das plantas. A lisina, cisteína, ornitina, arginina, triptofano e histidina foram acumulados em mais de um tecido nas plantas expostas ao Cd, assim como o galactinol. A glutationa (GSH), as fitoquelatinas (PCs) e seus homólogos foram fortemente induzidos pelo Cd, sendo que as plantas supridas com as doses de S de 1,9 e/ou 3,7 mmol L-1 apresentaram as maiores concentrações desses peptídeos. As plantas supridas com as maiores doses de S apresentaram menor peroxidação lipídica e maior taxa fotossintética, o que demonstra que o sistema antioxidante dessas plantas foi mais eficiente na atenuação dos danos causados pelo Cd. Diante desses resultados, fica claro que o capim-massai suprido adequadamente com S apresenta maior tolerância ao Cd, assim como maior potencial de fitoextração
250

Consequences of the Niger Delta Amnesty Program Implementation on Nigeria's Upstream Petroleum Industry

Ezeocha, Chisomaga Ihediohanma 01 January 2016 (has links)
The Niger Delta militancy ravaged the Nigerian upstream petroleum sector between 2004-2009, bringing it to a standstill. In response, the Nigerian state adopted an amnesty policy―a globally recognized tool for conflict resolution and peacebuilding―to protect the sector and the economy from collapse. Little is known, however, about the unintended consequences of the amnesty implementation for the Nigerian upstream petroleum sector. Thus, the purpose of this study was to fill this gap in the research literature on the Niger Delta amnesty program. Polarity management was the conceptual framework applied; relative deprivation and polarities of democracy constituted the theoretical foundation for this qualitative case study. Face-to-face interviews and focus group discussions were conducted with 29 purposefully selected participants from the senior ranks of the petroleum industry, sector trade unions, relevant government agencies, and a regional university. Data were inductively coded as part of content analysis, the data analysis strategy. Participants viewed the amnesty policy as being poorly conceived and implemented due to the many unintended negative consequences arising from the policy implementation. The key finding from the study indicates that both the sector and the Niger Delta region are worse off post the amnesty policy implementation. The study concludes that by adopting and implementing the study recommendations, stakeholders may be able to mitigate the identified unintended consequences, position the Nigerian upstream petroleum sector for sustainable growth, address the root causes of the militancy, and deliver a positive social change for the residents of Niger Delta.

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