969 resultados para Graham Foundation for Advanced Studies in the Fine Arts
Resumo:
Determining the relative roles of vicariance and selection in restricting gene flow between populations is of central importance to the evolutionary process of population divergence and speciation. Here we use molecular and morphological data to contrast the effect of isolation (by mountains and geographical distance) with that of ecological factors (altitudinal gradients) in promoting differentiation in the wedge-billed woodcreeper, Glyphorynchus spirurus, a tropical forest bird, in Ecuador. Tarsus length and beak size increased relative to body size with altitude on both sides of the Andes, and were correlated with the amount of moss on tree trunks, suggesting the role of selection in driving adaptive divergence. In contrast, molecular data revealed a considerable degree of admixture along these altitudinal gradients, suggesting that adaptive divergence in morphological traits has occurred in the presence of gene flow. As suggested by mitochondrial DNA sequence data, the Andes act as a barrier to gene flow between ancient subspecific lineages. Genome-wide amplified fragment length polymorphism markers reflected more recent patterns of gene flow and revealed fine-scale patterns of population differentiation that were not detectable with mitochondrial DNA, including the differentiation of isolated coastal populations west of the Andes. Our results support the predominant role of geographical isolation in driving genetic differentiation in G. spirurus, yet suggest the role of selection in driving parallel morphological divergence along ecological gradients.
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Colorectal and gastric cancers are the fourth and third leading causes of cancer death world-wide. Unfortunately, gastric cancer is usually diagnosed at an advanced stage after becoming metastatic in distant sites, so that palliative therapy is the mainstay of treatment. Major progress in the understanding of the biology, the development of valid biomarkers and molecular targeted drugs have improved the treatment options and prognosis of both cancers significantly in the last years. Here, we review the current standards of care for patients with advanced and metastatic colorectal and gastric cancer and outline the perspectives for the future.
Resumo:
PURPOSE: Advanced Practice Lung Cancer Nurses (APLCN) are well-established in several countries but their role has yet to be established in Switzerland. Developing an innovative nursing role requires a structured approach to guide successful implementation and to meet the overarching goal of improved nursing sensitive patient outcomes. The "Participatory, Evidence-based, Patient-focused process, for guiding the development, implementation, and evaluation of advanced practice nursing" (PEPPA framework) is one approach that was developed in the context of the Canadian health system. The purpose of this article is to describe the development of an APLCN model at a Swiss Academic Medical Center as part of a specialized Thoracic Cancer Center and to evaluate the applicability of PEPPA framework in this process. METHOD: In order to develop and implement the APLCN role, we applied the first seven phases of the PEPPA framework. RESULTS: This article spreads the applicability of the PEPPA framework for an APLCN development. This framework allowed us to i) identify key components of an APLCN model responsive to lung cancer patients' health needs, ii) identify role facilitators and barriers, iii) implement the APLCN role and iv) design a feasibility study of this new role. CONCLUSIONS: The PEPPA framework provides a structured process for implementing novel Advanced Practice Nursing roles in a local context, particularly where such roles are in their infancy. Two key points in the process include assessing patients' health needs and involving key stakeholders.
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Probiotic lactobacilli and bifidobacteria in the mouth – in vitro studies on saliva-mediated functions and acid production Probiotics are viable bacteria which, when used in adequate amounts, are beneficial to the health of the host. Although most often related to intestinal health, probiotic bacteria can be found also in the mouth after consumption of products that contain them. This study aimed at evaluating the oral effects of probiotic bacteria already in commercial use. In a series of in vitro studies, the oral colonisation potential of different probiotic bacteria, their acid production and potential saliva-mediated effects on oral microbial ecology were investigated. The latter included effects on the salivary pellicle, the adhesion of other bacteria, and the activation of the peroxidase system. Streptococcus mutans, Streptococcus gordonii, Aggregatibacter actinomycetemcomitans and Helicobacter pylori were used as bacterial indicators of the studied phenomena. There were significant differences between the probiotic strains in their colonisation potential. They all were acidogenic, although using different sugars and sugar alcohols. However, their acid production could be inhibited by the peroxidase system. Based on the results, it can be suggested that probiotic bacteria might influence the oral microbiota by different, partly species or strain-specific means. These include the inhibition of bacterial adhesion, modification of the enamel pellicle, antimicrobial activity, and activation of the peroxidase system. To conclude, probiotic strains differed from each other in their colonisation potential and other oral effects as evaluated in vitro. Both positive and potentially harmful effects were observed, but the significance of the perceived results needs to be further evaluated in vivo.
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The role of dopamine and serotonin in spinal pain regulation is well established. However, little is known concerning the role of brain dopamine and serotonin in the perception of pain in humans. The aim of this study was to assess the potential role of brain dopamine and serotonin in determining experimental pain sensitivity in humans using positron emission tomography (PET) and psychophysical methods. A total of 39 healthy subjects participated in the study, and PET imaging was performed to assess brain dopamine D2/D3 and serotonin 5-HT1A receptor availability. In a separate session, sensitivity to pain and touch was assessed with traditional psychophysical methods, allowing the evaluation of potential associations between D2/D3 and 5-HT1A binding and psychophysical responses. The subjects’ responses were also analyzed according to Signal Detection Theory, which enables separate assessment of the subject’s discriminative capacity (sensory factor) and response criterion (non-sensory factor). The study found that the D2/D3 receptor binding in the right putamen was inversely correlated with pain threshold and response criterion. 5-HT1A binding in cingulate cortex, inferior temporal gyrus and medial prefrontal cortex was inversely correlated with discriminative capacity for touch. Additionally, the response criterion for pain and intensity rating of suprathreshold pain were inversely correlated with 5-HT1A binding in multiple brain areas. The results suggest that brain D2/D3 receptors and 5-HT1A receptors modulate sensitivity to pain and that the pain modulatory effects may, at least partly, be attributed to influences on the response criterion. 5-HT1A receptors are also involved in the regulation of touch by having an effect on discriminative capacity.
Resumo:
The traditional forest industry is a good example of the changing nature of the competitive environment in many industries. Faced with drastic challenges forestindustry companies are forced to search for new value-creating strategies in order to create competitive advantage. The emerging bioenergy business is now offering promising avenues for value creation for both the forest and energy sectors because of their complementary resources and knowledge with respect to bioenergy production from forest-based biomass. The key objective of this dissertation is to examine the sources of sustainable competitive advantage and the value-creation opportunities that are emerging at the intersection between the forest and energy industries. The research topic is considered from different perspectives in order to provide a comprehensive view of the phenomenon. The study discusses the business opportunities that are related to producing bioenergy from forest-based biomass, and sheds light on the greatest challenges and threats influencing the success of collaboration between the forest and energy sectors. In addition, it identifies existing and potential bioenergy actors, and considers the resources and capabilities needed in order to prosper in the bioenergy field. The value-creation perspective is founded on strategic management accounting, the theoretical frameworks are adopted from the field of strategic management, and the future aspect is taken into account through the application of futures studies research methodology. This thesis consists of two parts. The first part provides a synthesis of the overall dissertation, and the second part comprises four complementary research papers. There search setting is explorative in nature, and both qualitative and quantitative research methods are used. As a result, the thesis lays the foundation for non-technological studies on bioenergy. It gives an example of how to study new value-creation opportunities at an industrial intersection, and discusses the main determinants affecting the value-creation process. In order to accomplish these objectives the phenomenon of value creation at the intersection between the forest and energy industries is theorized and connected with the dynamic resource-based view of the firm.
Resumo:
A spectrophotometric method based on the formation of ion-pair complex between haloperidol and eriochrome black T (EBT) at pH 1.85 has been described. The formed complex was extracted quantitatively into chloroform and measured at 510 nm. Infra red (IR) studies were performed to confirm the formation of ion-pair complex. Beer's law was obeyed in the concentration range of 2.0-9.0 µg mL-1 with molar absorptivity of 2.67 × 10(4) L mol-1 cm-1. The detection limit was found to be 0.18 µg mL-1. Statistical comparison of the results of the proposed method with those of the reference method shows excellent agreement and indicates no significant difference in accuracy and precision.
Resumo:
The determination of the total calcium in juice, syrups, and other products of the sugar industry is investigated. Total calcium and free calcium is determinated by AAS and employing Ca-selective electrode respectively. A coefficient is obtained for the relation of total calcium with respect to free calcium. The coefficient is employed to determine the content of total calcium in accordance with the following equation.
Resumo:
The offset printing process is complex and involves the meeting of two essentially complex materials, printing ink and paper, upon which the final product is formed. It can therefore be expected that a multitude of chemical and physical interactions and mechanisms take place at the ink-paper interface. Interactions between ink and paper are of interest to both the papermakers and ink producers, as they wish to achieve better quality in the final product. The objective of this work is to clarify the combined influence of paper coating structure, printing ink and fountain solution on ink setting and the problems related to ink setting. A further aim is to identify the mechanisms that influence ink setting problems, and to be able to counteract them by changing properties of the coating layer or by changing the properties of the ink. The work carried out for this thesis included use of many techniques ranging from standard paper and printability tests to advanced optical techniques for detection of ink filaments during ink levelling. Modern imaging methods were applied for assessment of ink filament remain sizes and distribution of ink components inside pigment coating layers. Gravimetric filtration method and assessment of print rub using Ink-Surface-Interaction-Tester (ISIT) were utilized to study the influence of ink properties on ink setting. The chemical interactions were observed with the help of modified thin layer chromatography and contact angle measurements using both conventional and high speed imaging. The results of the papers in this thesis link the press operational parameters to filament sizes and show the influence of these parameters to filament size distribution. The relative importance between the press operation parameters was shown to vary. The size distribution of filaments is important in predicting the ink setting behaviour, which was highlighted by the dynamic gloss and ink setting studies. Prediction of ink setting behaviour was also further improved by use of separate permeability factors for different ink types in connection to filtration equations. The roles of ink components were studied in connection to ink absorption and mechanism of print rub. Total solids content and ratio of linseed oil to mineral oil were found to determine the degree of print rub on coated papers. Wax addition improved print rub resistance, but would not decrease print rub as much as lowering the total solids content in the ink. Linseed oil was shown to absorb into pigment coating pores by mechanism of adsorption to pore walls, which highlights the need for sufficient pore surface area for improved chromatographic separation of ink components. These results should help press operators, suppliers of printing presses, papermakers and suppliers to papermakers, to better understand the material and operating conditions of the press as it relates to various print quality issues. Even though paper is in competition with electronic media, high quality printed products are still in demand. The results should provide useful information for this segment of the industry.
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The process of cold storage chambers contributes largely to the quality and longevity of stored products. In recent years, it has been intensified the study of control strategies in order to decrease the temperature change inside the storage chamber and to reduce the electric power consumption. This study has developed a system for data acquisition and process control, in LabVIEW language, to be applied in the cooling system of a refrigerating chamber of 30m³. The use of instrumentation and the application developed fostered the development of scientific experiments, which aimed to study the dynamic behavior of the refrigeration system, compare the performance of control strategies and the heat engine, even due to the controlled temperature, or to the electricity consumption. This system tested the strategies for on-off control, PID and fuzzy. Regarding power consumption, the fuzzy controller showed the best result, saving 10% when compared with other tested strategies.
Resumo:
Multiple sclerosis (MS) is a chronic immune-mediated inflammatory disorder of the central nervous system. MS is the most common disabling central nervous system (CNS) disease of young adults in the Western world. In Finland, the prevalence of MS ranges between 1/1000 and 2/1000 in different areas. Fabry disease (FD) is a rare hereditary metabolic disease due to mutation in a single gene coding α-galactosidase A (alpha-gal A) enzyme. It leads to multi-organ pathology, including cerebrovascular disease. Currently there are 44 patients with diagnosed FD in Finland. Magnetic resonance imaging (MRI) is commonly used in the diagnostics and follow-up of these diseases. The disease activity can be demonstrated by occurrence of new or Gadolinium (Gd)-enhancing lesions in routine studies. Diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI) are advanced MR sequences which can reveal pathologies in brain regions which appear normal on conventional MR images in several CNS diseases. The main focus in this study was to reveal whether whole brain apparent diffusion coefficient (ADC) analysis can be used to demonstrate MS disease activity. MS patients were investigated before and after delivery and before and after initiation of diseasemodifying treatment (DMT). In FD, DTI was used to reveal possible microstructural alterations at early timepoints when excessive signs of cerebrovascular disease are not yet visible in conventional MR sequences. Our clinical and MRI findings at 1.5T indicated that post-partum activation of the disease is an early and common phenomenon amongst mothers with MS. MRI seems to be a more sensitive method for assessing MS disease activity than the recording of relapses. However, whole brain ADC histogram analysis is of limited value in the follow-up of inflammatory conditions in a pregnancy-related setting because the pregnancy-related physiological effects on ADC overwhelm the alterations in ADC associated with MS pathology in brain tissue areas which appear normal on conventional MRI sequences. DTI reveals signs of microstructural damage in brain white matter of FD patients before excessive white matter lesion load can be observed on conventional MR scans. DTI could offer a valuable tool for monitoring the possible effects of enzyme replacement therapy in FD.