855 resultados para Idea of approaches to a number
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This paper applies a SRT framework to the study of two case studies, namely the recent campaign of opposition to the legalization of hydraulic fracking in the State of New York and the more ongoing debate on land leasing in Africa. In relation to both campaigns, the analysis accounts for the arguments of a major financial institution and industry representatives who stress the safe and value-adding dimensions of these practices, as well as the views of opponents who refute the validity of industry's position and point to the unacceptable risks posed to the community, health and the environment. In spite of a number of obvious differences between these two case studies, not least differences arising from contrasting socio-economic and geo-political settings, there were also some notable similarities. First, was a tendency amongst protesters in both cases to formulate their role as contemporaries in a historically extended struggle for democratic justice. All perceived of themselves as guardians of their community's right to resist a corporate 'invasion' of their territories, like their forefathers and mothers before them. A theme of colonialism was explored in both settings through various identity and thematic anchoring devices that deliberately evoked shared understandings and historical memories of exploitation and human suffering. The evocation of powerful symbols of identity through visual narratives of protest further reinforced the cultural comprehensibility of opponents' message of protest in both contexts.
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This PowerPoint presentation goes over the ways in which aquatics pest and weeds can be controlled.
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In evolution: that there are a myriad of ways a diversity of folks can archive digital documents (perhaps as print).Documents can only move through containers, and those containers rely on perception to be used.Further, the decision of what constitutes an archive is up to the archon.
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Poly(aryl-ether-ether-ketone) (PEEK) is a semi crystalline polymer which exhibits properties that make it an attractive choice for use as an implant material. It displays natural radiolucency, and MRI compatibility, as well as good chemical and sterilization resistance, both of which make it of particular interest in orthopaedic implants. However, PEEK has demonstrated poor cellular adhesion both in vitro and in vivo. This is problematic as implant surfaces that do not develop a layer of adhesive cells are at risk of undergoing fibrous encapsulation, which in turn leads to lack of a strong interface between the implant device and the patient tissue, which can in turn lead to failure of the implant and revision surgery . As incorporating nanotopography into a polymer surface has been demonstrated to be able to direct the differentiation behaviour of stem cells, a possible solution to PEEKs underlying issues with poor cellular response would be to incorporate specific nanoscale topography into the material surface through injection moulding, and then analysing if this is a viable method for addressing PEEKs issues with cellular response. In addition to nanoscale topography, the experimental PEEK surfaces were treated with oxygen plasma to address the underlying cytophobicity of the material. As this type of treatment has been documented to be capable of etching the PEEK surface, experiments were carried out to quantify the effect of this treatment, both on the ability of cells to adhere to the PEEK surface, as well as the effect it has upon the nanotopography present at the PEEK surface. The results demonstrated that there were a range of plasma treatments which would significantly improve the ability of cells to adhere to the PEEK surface without causing unacceptable damage to the nanotopography. Three different types of cells with osteogenic capacity were tested with the PEEK surfaces to gauge the ability of the topography to alter their behaviour: SAOS-2, osteoprogenitors and 271+ MSCs. Due to PEEKs material properties (it is non transparent, exhibits birefringence and is strongly autofluorescent) a number of histological techniques were used to investigate a number of different stages that take place in osteogenesis. The different cell types did display slightly different responses to the topographies. The SAOS-2 cells cultured on surfaces that had been plasma treated for 2 minutes at 200W had statistically significantly higher levels of von Kossa staining on the NSQ surface compared to the planar surface, and the same experiment employing alizarin red staining, showed a statistically significantly lower level of staining on the SQ surface compared to the planar surface. Using primary osteoprogenitor cells designed to look into if whether or not the presence of nanotopography effected the osteogenic response of these cells, we saw a lack of statistically significant difference produced by the surfaces investigated. By utilising HRP based immunostaining, we were able to investigate, in a quantitative fashion, the production of the two osteogenic markers osteopontin and osteocalcin by cells. When stained for osteocalcin, the SQ nanotopography had total percentage of the surface with stained material, average area and average perimeter all statistically significantly lower than the planar surface. For the cells that were stained for osteopontin, the SQ nanotopgraphy had a total percentage of the surface with stained material, average area and average perimeter all highly statistically significantly lower than those of the planar surface. Additionally, for this marker the NSQ nanotopography had average areas and average perimeters that were highly significantly higher than those of the planar surface. There were no significant differences for any of the values investigated for the 271+ MSC’s When plasma treatment was varied, the SAOS-2 cells demonstrated an overall trend i.e. increasing the energy of plasma treatment in turn leads to an increase in the overall percentage of staining. A similar experiment employing stem cells isolated from human bone marrow instead of SAOS-2 cells showed that for polycarbonate surfaces , used as a control, mineralization is statistically significantly higher on the NSQ nanopattern compared to the planar surface, whereas on the PEEK surfaces we observe the opposite trend i.e. the NSQ nanotopography having a statistically significantly lower amount of mineralization compared to the planar surface at the 200W 2min and 30W 1min plasma treatments. The standout trend from the PEEK results in this experiment was that the statistically significant differences on the PEEK substrates were clustered around the lower energy plasma treatments, which could suggest that the plasma treatment disrupted a function of the nanotopograhy which is why, as the energy increases, there are less statistically significant differences between the NSQ nanotopography and the Planar surface This thesis documents the response of a number of different types of cells to specific nanoscale topographies incorporated into the PEEK surface which had been treated with oxygen plasma. It outlines the development of a number of histological methods which measure different aspects of osteogenesis, and were selected to both work with PEEK, and produce quantitative results through the use of Cell Profiler. The methods that have been employed in this body of work would be of interest to other researchers working with this material, as well as those working with similarly autofluorescent materials.
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Kenia liegt in den Äquatorialtropen von Ostafrika und ist als ein weltweiter Hot-Spot für Aflatoxinbelastung insbesondere bei Mais bekannt. Diese toxischen und karzinogenen Verbindungen sind Stoffwechselprodukte von Pilzen und so insbesondere von der Wasseraktivität abhängig. Diese beeinflusst sowohl die Trocknung als auch die Lagerfähigkeit von Nahrungsmitteln und ist somit ein wichtiger Faktor bei der Entwicklung von energieeffizienten und qualitätsorientierten Verarbeitungsprozessen. Die vorliegende Arbeit hat sich zum Ziel gesetzt, die Veränderung der Wasseraktivität während der konvektiven Trocknung von Mais zu untersuchen. Mittels einer Optimierungssoftware (MS Excel Solver) wurde basierend auf sensorerfassten thermo-hygrometrischen Daten der gravimetrische Feuchteverlust von Maiskolben bei 37°C, 43°C und 53°C vorausberechnet. Dieser Bereich stellt den Übergang zwischen Niedrig- und Hochtemperaturtrocknung dar. Die Ergebnisse zeigen deutliche Unterschiede im Verhalten der Körner und der Spindel. Die Trocknung im Bereich von 35°C bis 45°C kombiniert mit hohen Strömungsgeschwindigkeiten (> 1,5 m / s) begünstigte die Trocknung der Körner gegenüber der Spindel und kann daher für eine energieeffiziente Trocknung von Kolben mit hohem Anfangsfeuchtegehalt empfohlen werden. Weitere Untersuchungen wurden zum Verhalten unterschiedlicher Schüttungen bei der bei Mais üblichen Satztrocknung durchgeführt. Entlieschter und gedroschener Mais führte zu einem vergrößerten Luftwiderstand in der Schüttung und sowohl zu einem höheren Energiebedarf als auch zu ungleichmäßigerer Trocknung, was nur durch einen erhöhten technischen Aufwand etwa durch Mischeinrichtungen oder Luftumkehr behoben werden könnte. Aufgrund des geringeren Aufwandes für die Belüftung und die Kontrolle kann für kleine landwirtschaftliche Praxisbetriebe in Kenia daher insbesondere die Trocknung ganzer Kolben in ungestörten Schüttungen empfohlen werden. Weiterhin wurde in der Arbeit die Entfeuchtung mittels eines Trockenmittels (Silikagel) kombiniert mit einer Heizquelle und abgegrenztem Luftvolumen untersucht und der konventionellen Trocknung gegenüber gestellt. Die Ergebnisse zeigten vergleichbare Entfeuchtungsraten während der ersten 5 Stunden der Trocknung. Der jeweilige Luftzustand bei Verwendung von Silikagel wurde insbesondere durch das eingeschlossene Luftvolumen und die Temperatur beeinflusst. Granulierte Trockenmittel sind bei der Maistrocknung unter hygienischen Gesichtspunkten vorteilhaft und können beispielsweise mit einfachen Öfen regeneriert werden, so dass Qualitätsbeeinträchtigungen wie bei Hochtemperatur- oder auch Freilufttrocknung vermieden werden können. Eine hochwertige Maistrocknungstechnik ist sehr kapitalintensiv. Aus der vorliegenden Arbeit kann aber abgeleitet werden, dass einfache Verbesserungen wie eine sensorgestützte Belüftung von Satztrocknern, der Einsatz von Trockenmitteln und eine angepasste Schüttungshöhe praktikable Lösungen für Kleinbauern in Kenia sein können. Hierzu besteht, ggf. auch zum Aspekt der Verwendung regenerativer Energien, weiterer Forschungsbedarf.
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Public policies to support entrepreneurship and innovation play a vital role when firms have difficulties in accessing external finance. However, some authors have found evidence of long-term inefficiency in subsidized firms (Bernini and Pelligrini, 2011; Cerqua and Pelligrini, 2014) and ineffectiveness of public funds (Jorge and Suárez, 2011). The aim of the paper is to assess the effectiveness in the selection process of applications to public financial support for stimulating innovation. Using a binary choice model, we investigate which factors influence the probability of obtaining public support for an innovative investment. The explanatory variables are connected to firm profile, the characteristics of the project and the macroeconomic environment. The analysis is based on the case study of the Portuguese Innovation.Incentive System (PIIS) and on the applications managed by the Alentejo Regional Operational Program in the period 2007 – 2013. The results show that the selection process is more focused on the expected impact of the project than on the firm’s past performance. Factors that influence the credit risk and the decision to grant a bank loan do not seem to influence the government evaluator regarding the funding of some projects. Past activities in R&D do not significantly affect the probability of having an application approved under the PIIS, whereas an increase in the number of patents and the number of skilled jobs are both relevant factors. Nevertheless, some evidence of firms’ short-term inefficiency was found, in that receiving public financial support is linked to a smaller increase in productivity compared to non-approved firm applications. At the macroeconomic level, periods with a higher cost of capital in financial markets are linked to a greater probability of getting an application for public support approved, which could be associated with the effectiveness of public support in correcting market failings.
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Cabeça de xara is a ready-to-eat meat product, whose production is very characteristic in Alentejo, a particular region of Portugal. It is a galantine usually moulded into parallelepiped shape made with various meats obtained from the Alentejano pig breed reared in the same region, namely deboned pork heads, tongue and connective tissue to which a number of condiments like salt, parsley, wine and pepper, are added. This work intended to test the feasibility of adding vinegar in order to increase the shelf-life of cabeça de xara, by reducing the contaminating microbiota responsible for spoilage, as well as controlling the pathogen Listeria monocytogenes. Three independent batches were produced and proximate composition, pH, aw, microbiological parameters and biogenic amines content evaluated. A sensory analysis was also performed throughout the storage period. No significant differences between control and vinegar samples was found regarding the proximate composition of cabeça de xara. As expected, pH is lower in the vinegar samples, however no differences in aw were observed between the two treatments. L. monocytogenes was present from the first month on only in one batch in the control treatment. However, it is inhibited by the addition of vinegar until the third month of storage, where L. monocytogenes is present but below the limit established in the 2073/2005 regulation. The presence of vinegar significantly decreased the content in biogenic amines, particularly cadaverine, putrescine and tyramine, throughout the storage period. Concerning sensory evaluation, no vinegar taste was reported by the panellists in a depreciating way.
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2011
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Asymmetric organocatalysed reactions are one of the most fascinating synthetic strategies which one can adopt in order to induct a desired chirality into a reaction product. From all the possible practical applications of small organic molecules in catalytic reaction, amine–based catalysis has attracted a lot of attention during the past two decades. The high interest in asymmetric aminocatalytic pathways is to account to the huge variety of carbonyl compounds that can be functionalized by many different reactions of their corresponding chiral–enamine or –iminium ion as activated nucleophile and electrophile, respectively. Starting from the employment of L–Proline, many useful substrates have been proposed in order to further enhance the catalytic performances of these reaction in terms of enantiomeric excess values, yield, conversion of the substrate and turnover number. In particular, in the last decade the use of chiral and quasi–enantiomeric primary amine species has got a lot of attention in the field. Contemporaneously, many studies have been carried out in order to highlight the mechanism through which these kinds of substrates induct chirality into the desired products. In this scenario, computational chemistry has played a crucial role due to the possibility of simulating and studying any kind of reaction and the transition state structures involved. In the present work the transition state geometries of primary amine–catalysed Michael addition reaction of cyclohexanone to trans–β–nitrostyrene with different organic acid cocatalysts has been studied through different computational techniques such as density functional theory based quantum mechanics calculation and force–field directed molecular simulations.
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The PhD research project was a striking example of the enhancement of milling by-product and alternative protein sources from house cricket (Acheta domesticus), conceived as sustainable and renewable sources, to produce innovative food products. During milling processing of wheat and rye, several by-products with high technological and functional potential, are produced. The use of selected microbial consortia, allowed to obtain a pre-fermented ingredient for use in the bakery. The pre-ferments obtained were characterized by a high technological, functional and nutritional value, also interesting from a nutraceutical point of view. Bakery products obtained by the addition of pre-fermented ingredients were characterized by a greater quantity of aromatic molecules and an increase in SCFA, antioxidant activity, total amino acids and total phenols resulting in positive effect on the functionality. Moreover, the industrial scaling-up of pre-ferment and innovative bakery goods production, developed in this research, underlined the technological applicability of pre-fermented ingredients on a large scale. Moreover, the identification of innovative protein sources, can address the request of new sustainable ingredients able to less impact on the environment and to satisfy the food global demand. To upscale the insect production and ensure food safety of insect-based products, biotechnological formulations based on Acheta domesticus powder were optimized. The use of Yarrowia lipolytica in the biotechnological transformation of cricket powder led to the achievement of a cricket-based food ingredient characterized by a reduced content of chitin and an increase of antimicrobial and health-promoting molecules. The innovative bakery products containing cricket-based hydrolysates from Y. lipolytica possessed specific sensory, qualitative and functional characteristics to the final product. Moreover, the combination of Y. lipolytica hydrolysis and baking showed promising results regarding a reduced allergenicity in cricket-based baked products. Thus, the hydrolysate of cricket powder may represent a versatile and promising ingredient in the production of innovative foods.
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This study investigated the effect of the incorporation of an iodonium salt in experimental composites, on the bond strength of metallic brackets bonded to bovine teeth. Two hundred and seventy bovine teeth were embedded in self-curing acrylic resin and divided into 18 groups (n=15), according to the experimental composite with an iodonium salt at molar concentrations 0 (control), 0.5, or 1%; the light-activation times (8, 20 and 40 s); and the storage times (10 min or 24 h). Metallic brackets were fixed on the tooth surface using experimental composites. Photoactivation was performed with a quartz-tungsten-halogen light-curing unit curing unit for 8, 20 and 40 s. The specimens were stored in distilled water at 37 °C for 10 min or 24 h and submitted to bond strength test at 0.5 mm/min. The data were subjected to three-way ANOVA and Tukey's test (α=0.05). The Adhesive Remnant Index (ARI) was used to classify the failure modes. The shear bond strengths (MPa) at 10 min for light-activation times of 8, 20 and 40 s were: G1 - 4.6, 6.9 and 7.1; G2 - 8.1, 9.2 and 9.9; G3 - 9.1, 10.4 and 10.7; and at 24 h were: G1 - 10.9, 11.1 and 11.7; G2 - 11.8, 12.7 and 14.2; G3 - 12.1, 14.4 and 15.8. There was a predominance of ARI score 3 for groups with 10 min storage time, and ARI score 2 for groups with 24 h storage time. In conclusion, the addition of iodonium salt (C05 and C1) to the experimental composite may increase the bond strength of brackets to bovine enamel using reduced light exposure times.
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To determine the prevalence of the Papanicolaou exam among women aged 20 to 59 years in the city of Campinas (state of São Paulo, Brazil) and to analyze associations between this test and affiliation to private health insurance plans as well as socioeconomic/demographic variables and health-related behavior. To do so, a population-based, cross-sectional study was carried out. Statistical analyses took the study design into account. Despite the significant socioeconomic differences between women with and without private health plans, no differences between these groups were found regarding having been submitted to the Papanicolaou test. In fact no differences were found as to socioeconomic and health variables analyzed. Among all variables analyzed, only marital status was significantly associated with having undergone the test. The Brazilian public health system accounted for 55.7% of the exams. The present findings indicate social equity in the city of Campinas regarding the preventive exam for cervical cancer in the age group studied.
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Primary X-ray spectra were measured in the range of 80-150kV in order to validate a computer program based on a semiempirical model. The ratio between the characteristic and total air Kerma was considered to compare computed results and experimental data. Results show that the experimental spectra have higher first HVL and mean energy than the calculated ones. The ratios between the characteristic and total air Kerma for calculated spectra are in good agreement with experimental results for all filtrations used.
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The aim of this study was to verify the drying effect on the reproducibility of DIAGNOdent (Dd) devices to detect caries-like lesions. Three areas were created in each of the 34 bovine incisors: sound (S), demineralized (DE) and remineralized (RE). One examiner measured each area with two Dd devices (denominated X and Y), twice under humid, and twice under dry condition. Intra-rater agreement according each device and inter-device agreement were estimated by kappa statistics (k). Intra-rater agreement for device Y was substantial under humid (k DE=0.68 and k RE+S=0.68) and dry condition (k DE=0.64 and k RE+S=0.67). For device X, it was substantial under humid condition (k DE=0.57 and k RE+S=0.49), and it was almost perfect after air drying (k DE=1.0 and kRE+S=1.0). Inter-device agreement was slight (k =0.17) under humid condition, and it was substantial under dry condition (k =0.62). As reproducibility increased under dry condition, drying is advised to detect caries-like lesions on free smooth surfaces when different devices are used.