985 resultados para Dental plaque chemical control


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The effect of chemical and biological treatments on castor bean emergence, seedling vigor, dry matter production, and also the control of microorganisms associated with seeds of the AL Guarany 2002 and Lyra cultivars, was evaluated. The products tested were carbendazim + thiram, carboxin + thiram and a product based on Trichoderma. Total seed and seedling emergence were evaluated at 27 days after sowing whereas dry matter production was verified for plants removed 45 days after sowing. The Guarany 2002 AL cultivar had a higher incidence of microorganisms than the Lyra cultivar. The chemical treatment was 100% effective in controlling fungi but the biological treatment did not reduce microorganism incidence on the seeds. Chemical treatment resulted in plants with more dry matter and the best results were for carbendazim + thiram and carboxin + thiram at doses of 60 g + 140 g and 50 g + 50 g/100 kg of seeds, respectively. The carbendazim + thiram mixture was the only treatment which was statistically higher for total emergence whereas the biological treatment increased emergence only for the Lyra cultivar, thus demonstrating its lower efficiency. The importance of fungicides to control pathogens associated with seeds was discussed.

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This thesis was conducted on assignment by a multinational chemical corporation as a case study. The purpose of this study is to find ways to improve the purchasing process for small purchases at the case company. The improvements looked after are mainly cost and time savings. Purchasing process is the process that starts from the requisition of goods or services and ends when the invoice is paid. In this thesis the purchases with value less than 1000€ are considered to be small. The theoretical framework of the thesis consists of general theoretical view of costs and performance of the purchasing process, different types of purchasing processes and a model for improving purchasing processes. The categorization to small and large purchases is the most important followed by the division between direct and indirect purchases. Also models that provide more strategic perspective for categorization were found to be useful. Auditing and managerial control are important parts of the purchasing process. When considering the transaction costs of purchasing from the costs–benefits perspective large and small purchases should not have the same processes. Purchasing cards, e-procurement and vendor managed inventory are seen as an alternative to the traditional purchasing process. The empirical data collection was done by interviewing the company employees that take part of the purchasing process in their daily work. The interviews had open-ended questions and the answers were coded and analyzed. The results consist of process description and assessment as well as suggestions for potential improvements. At the case company the basic purchasing process was similar to the traditional purchasing process that is entirely done with computers and online. For some categories there was already more sophisticated e-procurement solutions in use. To improve the current e-procurement based solutions elimination of authorization workflow and better information exchange can be seen as potential improvements for most of the case purchases. Purchasing cards and a lightweight form of vendor managed inventory can be seen as potential improvements for some categories. Implementing the changes incurs at least some cost and the benefits might be hard to measure. This thesis has revealed that the small purchases have potential for significant cost and time savings at the case company.

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The purpose of this study was to evaluate the oral health status of residents residing in 2 long-term care facilities and determine if dental hygiene education was required in order to improve their current oral health. The oral health status of 6 independent and 4 dependent individuals residing in 2 long-term care facilities was evaluated. In addition, the current oral health and disease prevention practices employed by 4 caregivers who were responsible for providing oral care to dependent residents in the long-term care facilities were evaluated. Furthermore, an evaluation of the oral care practices of independent residents who were responsible for providing their own care was conducted. Finally, the challenges that caregivers and independent residents faced when performing oral care were determined, and methodological changes were proposed. Using a generic qualitative research methodology, data collection was comprised of semi structured interviews, field observations, and documentation. The oral health status of the residents was reevaluated 3 months later. The findings of this study demonstrated an increase in plaque accumulation, gingival inflammation, and unhealthy gingival tissue colour changes among the residents over the 3-month period. The study revealed that poor oral health among the residents was a result of inadequate oral hygiene care techniques, difficulties accessing oral health care, financial limitations, insufficient care staff, insufficient time for personal care duties, lack of professional development, minimal interprofessional collaboration of health disciplines, and lack of perseverance on the part of the caregivers and residents. Overall, oral health is essential, and maintaining optimal oral health requires increased collaboration and communication between health care providers.

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Introduction : Les soins dentaires des enfants autistes représentent un défi pour les parents et les dentistes. Des efforts doivent être faits afin d’améliorer les mesures préventives et l’éducation des parents. Recension des écrits : L’autisme se définit comme un désordre qualitatif de l’interaction sociale et de la communication, par des comportements ou activités répétitifs et stéréotypés et par de l’hypersensibilité aux stimuli corporels. Le manque de coopération pour le brossage des dents constitue un obstacle au maintien d’une bonne hygiène bucco-dentaire chez l’enfant autiste. Problématique : L’enfant autiste représente un défi pour le dentiste, mais aussi pour ses parents lors des mesures quotidiennes d’hygiène. Peu d’études cliniques se sont penchées sur l’utilité des pictogrammes dans la dispensation des soins dentaires quotidiens et professionnels de cette clientèle. Hypothèse de recherche : L’utilisation de pictogrammes améliore la coopération des enfants autistes pour les soins dentaires quotidiens et chez le dentiste, leur procurant une meilleure hygiène bucco-dentaire. Matériels et méthodes : Selon un devis d’étude expérimentale randomisée, 17 participants expérimentaux (avec pictogrammes) et 18 participants contrôles ont été recrutés au CHU Sainte-Justine, puis évalués à 6 reprises sur 12 mois. L’hygiène fut notée par l’indice de plaque et le comportement par l’échelle de Frankl. Résultats : Aucune différence significative n’a été notée entre le groupe expérimental et contrôle pour l’indice de plaque et l’échelle de Frankl. Globalement, une baisse de l’indice de plaque et une amélioration du comportement ont été notées pour les deux groupes et ce, pendant la période d’étude de 12 mois. Conclusion : Les résultats de la présente étude ne permettent pas d’affirmer que les pictogrammes contribuent à améliorer l’hygiène bucco-dentaire et le comportement des enfants autistes lors des soins dentaires quotidiens et professionnels.

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Chemical bath deposition (CBD)is one of the simplest, very convient and probably the cheapest method for thin film preparation. Photovoltaic is the cleanest and the most efficient mode of conversion of energy to electrical power. Silicon is the most popular material in this field. The present study on chemical bath deposited semiconducting copper selenide and iron sulfide thin films useful for photovoltaic applications. Semiconducting thin films prepared by chemical deposition find applications as photo detectors, solar control coatings and solar cells. Copper selenide is a p-type semiconductor that finds application in photovolitics. Several heterojunction systems such as Cu2-xSe/ZnSe (for injection electro luminescence), Cu2Se/AgInSe2 and Cu2Se/Si (for photodiodes), Cu2-xSe/CdS, Cu2-xSe/CdSe, CuxSe/InP and Cu2-xSe/Si for solar cells are reported. A maximum efficiency of 8.3% was achieved for the Cu2-xSe/Si cell, various preparation techniques are used for copper selenide like vacuum evaporation, direct reaction, electrodeposition and CBD. Instability of the as-prepared films was investigation and is accounted as mainly due to deviation from stoichiometry and the formation of iron oxide impurity. A sulphur annealing chamber was designed and fabricated for this work. These samples wee also analysed using optical absorption technique, XPS (X-ray Photoelectron Spectroscopy) and XRD.(X-Ray Diffraction).The pyrite films obtained by CBD technique showed amorphous nature and the electrical studies carried out showed the films to be of high resistive nature. Future work possible in the material of iron pyrite includes sulphur annealing of the non-stochiometric iron pyrite CBD thin films in the absence of atmospheric oxygen

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The objective of the preset work is to develop optical fiber sensors for various physical and chemical parameters. As a part of this we initially investigated trace analysis of silica, ammonia, iron and phosphate in water. For this purpose the author has implemented a dual wavelength probing scheme which has many advantages over conventional evanescent wave sensors. Dual wavelength probing makes the design more reliable and repeatable and this design makes the sensor employable for concentration, chemical content, adulteration level, monitoring and control in industries or any such needy environments. Use of low cost components makes the system cost effective and simple. The Dual wavelength probing scheme is employed for the trace analysis of silica, iron, phosphate, and ammonia in water. Such sensors can be employed for the steam and water quality analysers in power plants. Few samples from a power plant are collected and checked the performance of developed system for practical applications.

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Chaos is a subject oftopical interest and, studied in great detail in relation to its relevance in almost all branches of science, which include physical, chemical, and biological fields. Chaos in the literal sense signifies utter confusion, but the scientific community has differentiated chaos as deterministic chaos and white noise. Deterministic chaos implies the complex behaviour of systems, which are governed by deterministic laws. Behaviour of such systems often become unpredictable in the long run. This unpredictability arises from the sensitivity of the system to its initial conditions. The essential requirement for ‘sensitivity to initial condition’ is nonlinearity of the system. The only method for determining the future of such systems is numerically simulating its final state from a set ofinitial conditions. Synchronisation

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The term ‘water pollution’ broadly refers to the contamination of water and water bodies (e.g. lakes, rivers, oceans, groundwater etc). Water pollution occurs when pollutants are discharged directly or indirectly into water bodies without adequate treatment to remove the harmful contaminants. This affects not only the plants and organisms living in these bodies of water but also the entire natural biological communities and the biodiversity.Advanced Oxidation Processes (AOPs) have been tested as environment-friendly techniques for the treatment of contaminated water, in view of their ability to convert pollutants into harmless end products. These techniques refer to a set of treatment procedures designed to remove organic or inorganic contaminants in wastewater by oxidation. The contaminants are oxidized by different reagents such as air, oxygen, ozone, and hydrogen peroxide which are introduced in precise, preprogrammed dosages, sequences and combinations under appropriate conditions. The procedure when combined with light in presence of catalyst is known as photocatalysis. When ultrasound (US) is used as the energy source, the process is referred as sonication. Sonication in presence of catalyst is referred as sonocatalysis. Of late, combination of light and sound as energy sources has been tested for the decontamination of wastewater in the presence of suitable catalyst. In this case, the process is referred as sonophotocatalysis. These AOPs are specially advantageous in pollution control and waste water treatment because unlike many other technologies, they do not just transfer the pollutant from one phase to another but completely degrade them into innocuous substances such as CO2 and H2O.

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The traditional control of Imperata brasiliensis grasslands used by farmers in the Peruvian Amazon is to burn the grass. The objective of this study was to compare different methods of short-term control. Biological, mechanical, chemical and traditional methods of control were compared. Herbicide spraying and manual weeding have shown to be very effective in reducing above- and below-ground biomass growth in the first 45 days after slashing the grass, with effects persisting in the longer term, but both are expensive methods. Shading seems to be less effective in the short-term, whereas it influences the Imperata growth in the longer term. After one year shading, glyphosate application and weeding significantly reduced aboveground biomass by 94, 67 and 53%; and belowground biomass by 76, 65 and 58%, respectively, compared to control. We also found a significant decrease of Imperata rhizomes in soil during time under shading. Burning has proved to have no significant effect on Imperata growth. The use of shade trees in a kind of agroforestry system could be a suitable method for small farmers to control Imperata grasslands.

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Optimal control theory is a powerful tool for solving control problems in quantum mechanics, ranging from the control of chemical reactions to the implementation of gates in a quantum computer. Gradient-based optimization methods are able to find high fidelity controls, but require considerable numerical effort and often yield highly complex solutions. We propose here to employ a two-stage optimization scheme to significantly speed up convergence and achieve simpler controls. The control is initially parametrized using only a few free parameters, such that optimization in this pruned search space can be performed with a simplex method. The result, considered now simply as an arbitrary function on a time grid, is the starting point for further optimization with a gradient-based method that can quickly converge to high fidelities. We illustrate the success of this hybrid technique by optimizing a geometric phase gate for two superconducting transmon qubits coupled with a shared transmission line resonator, showing that a combination of Nelder-Mead simplex and Krotov’s method yields considerably better results than either one of the two methods alone.

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Realizar un trabajo que sirva de guía a los maestros asturianos, que voluntariamente quieran aplicar en sus aulas este programa y de fuente de información para cualquier docente o sanitario preocupado por la salud y por la educación sobre la misma. Educación para la prevención de la caries dental. Se elaboran seis bloques de actividades dirigidos a otros colectivos de personas diferentes: Actividades con el profesorado no diplomado en educación. Actividades con el colectivo de padres de alumnos. Actividades con alumnos de Ciclo Inicial, Ciclo Medio y Ciclo Superior. Dentro de cada uno de estos bloques se proponen objetivos, contenidos, actividades, materiales, etc. para el desarrollo del proyecto pedagógico sobre el tema. La información para desarrollar esta investigación, se obtiene fundamentalmente de la bibliografía. Se proponen por otra parte varios cuestionarios diferentes dirigidos a los distintos colectivos, también se ofrecen distintos instrumentos para la observación, como los anecdotarios y las listas de control. Se realiza un análisis de los objetivos, contenidos en los programas renovados, por bloques temáticos, en los que desde distintos enfoques se puede abordar la profilaxis de la caries dental, con delimitación de ciclos y areas de conocimiento. En las actividades dedicadas al nivel de Preescolar, se parte de un análisis de la psicología del niño en estos niveles, para fundamentar la actividad didáctica. Se plantean una serie de recursos al profesorado para presentar y desarrollar en el aula el tema de la profilaxis de la caries dental. Se relacionan: fichas, ejercicios, cuestionarios, textos, dramatizaciones, cuentos, etc.

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The present success in the manufacture of multi-layer interconnects in ultra-large-scale integration is largely due to the acceptable planarization capabilities of the chemical-mechanical polishing (CMP) process. In the past decade, copper has emerged as the preferred interconnect material. The greatest challenge in Cu CMP at present is the control of wafer surface non-uniformity at various scales. As the size of a wafer has increased to 300 mm, the wafer-level non-uniformity has assumed critical importance. Moreover, the pattern geometry in each die has become quite complex due to a wide range of feature sizes and multi-level structures. Therefore, it is important to develop a non-uniformity model that integrates wafer-, die- and feature-level variations into a unified, multi-scale dielectric erosion and Cu dishing model. In this paper, a systematic way of characterizing and modeling dishing in the single-step Cu CMP process is presented. The possible causes of dishing at each scale are identified in terms of several geometric and process parameters. The feature-scale pressure calculation based on the step-height at each polishing stage is introduced. The dishing model is based on pad elastic deformation and the evolving pattern geometry, and is integrated with the wafer- and die-level variations. Experimental and analytical means of determining the model parameters are outlined and the model is validated by polishing experiments on patterned wafers. Finally, practical approaches for minimizing Cu dishing are suggested.

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The present success in the manufacture of multi-layer interconnects in ultra-large-scale integration is largely due to the acceptable planarization capabilities of the chemical-mechanical polishing (CMP) process. In the past decade, copper has emerged as the preferred interconnect material. The greatest challenge in Cu CMP at present is the control of wafer surface non-uniformity at various scales. As the size of a wafer has increased to 300 mm, the wafer-level non-uniformity has assumed critical importance. Moreover, the pattern geometry in each die has become quite complex due to a wide range of feature sizes and multi-level structures. Therefore, it is important to develop a non-uniformity model that integrates wafer-, die- and feature-level variations into a unified, multi-scale dielectric erosion and Cu dishing model. In this paper, a systematic way of characterizing and modeling dishing in the single-step Cu CMP process is presented. The possible causes of dishing at each scale are identified in terms of several geometric and process parameters. The feature-scale pressure calculation based on the step-height at each polishing stage is introduced. The dishing model is based on pad elastic deformation and the evolving pattern geometry, and is integrated with the wafer- and die-level variations. Experimental and analytical means of determining the model parameters are outlined and the model is validated by polishing experiments on patterned wafers. Finally, practical approaches for minimizing Cu dishing are suggested.

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La monografía presenta la auto-organización sociopolítica como la mejor manera de lograr patrones organizados en los sistemas sociales humanos, dada su naturaleza compleja y la imposibilidad de las tareas computacionales de los regímenes políticos clásico, debido a que operan con control jerárquico, el cual ha demostrado no ser óptimo en la producción de orden en los sistemas sociales humanos. En la monografía se extrapola la teoría de la auto-organización en los sistemas biológicos a las dinámicas sociopolíticas humanas, buscando maneras óptimas de organizarlas, y se afirma que redes complejas anárquicas son la estructura emergente de la auto-organización sociopolítica.

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La present tesi intenta obtenir noves dades referents a la biologia i ecologia de la formiga argentina que poden arribar a ser cabdals per al disseny o millora de noves metodologies de control de l'expansió de la plaga en ecosistemes naturals. Així doncs, l'estudi de l'activitat de cerca d'aliment i del seu espectre dietari en ecosistemes naturals, juntament amb el de les fluctuacions estacionals de la densitat de reines en nius naturals, obre les portes a la millora de mètodes de control de la plaga mitjançant esquers tòxics d'efecte retardat i a l'aplicació de noves metodologies de control sense l'ús d'agents químics basats en l'eliminació massiva de reines. La tesi també aporta noves dades sobre la fisiologia reproductiva de l'espècie en relació a la temperatura, la qual cosa permet la integració de l'aspecte fisiològic en models de predicció del rang potencial d'establiment de la plaga en ecosistemes naturals, aspecte fins ara pràcticament oblidat en aquest tipus de models predictius.