927 resultados para Not a passing phase : reclaiming lesbians in history 1840-1985


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PURPOSE: To assess the correlation between changes in corneal aberrations and the 2-year change in axial length in children fitted with orthokeratology (OK) contact lenses. METHODS: Thirty-one subjects 6 to 12 years of age and with myopia −0.75 to −4.00DS and astigmatism ≤1.00DC were fitted with OK. Measurements of axial length and corneal topography were taken at regular intervals over a 2-year period. Corneal topography at baseline and after 3 and 24 months of OK lens wear was used to derive higher-order corneal aberrations (HOA) that were correlated with OK-induced axial length changes at 2 years. RESULTS: Significant changes in C3, C4, C4, root mean square (RMS) secondary astigmatism and fourth and total HOA were found with both 3 and 24 months of OK lens wear in comparison with baseline (all P0.05). Coma angle of orientation changed significantly pre-OK in comparison with 3 and 24 months post-OK as well as secondary astigmatism angle of orientation pre-OK in comparison with 24 months post-OK (all P0.05). DISCUSSION: Short-term and long-term OK lens wear induces significant changes in corneal aberrations that are not significantly correlated with changes in axial elongation after 2-years.

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The town of Sopron (Ödenburg) is situated near the western border of Hungary at the junction of major routes of commerce, no further than 70 km from Vienna. As early as in 1291 the town had become a chartered town or free royal town, which meant the most fully-fledged municipial autonomy in this period. The town was subordinated only to the king and could represent itself in parliament from 1445. The surrounding seigniorial towns and villages often lodged an appeal with the Town Court due to its wide legal autonomy. The inhabitants of seigniorial towns and the villagers could have been under the necessity of going to the town, and the legal proceedings they experienced in Sopron may have meant a model pattern for them. The seigniorial town (oppidum) is a settlement under the landlord's authority, with limited legal privileges, concentrated mostly on agricultural production and on the exchange of products of its immediate hinterland. Sopron as a county town was gradually becoming significant during the early modern period. The county (megye) was not only the unit of administration in Hungary, but that of the autonomy of nobility, too. The importance of Sopron as a county town attracted many noblemen dwelling in Sopron county to the town. The county was one of the most densely populated in the 15-18th c., at the beginning of the 18th c., for example, the density was 32 person/km2 and it rose more than 40 p/km2 by the end of the century. The population of Sopron was approximately 3500-3700 in the middle of the 15th c., and due to the decline during the later decades some 3000 persons lived in the town in the early 16th c. According to the first national census the population of Sopron was 12600 in 1784-87. These data place Sopron at the high level of Hungarian urban hierarchy in this period. This paper will explore two significant aspects of the relation between the town and its countryside: the problems of mutual economic dependence and the role of Sopron as a centre of culture.

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Due to low cost and easy deployment, multi-hop wireless networks become a very attractive communication paradigm. However, IEEE 802.11 medium access control (MAC) protocol widely used in wireless LANs was not designed for multi-hop wireless networks. Although it can support some kinds of ad hoc network architecture, it does not function efficiently in those wireless networks with multi-hop connectivity. Therefore, our research is focused on studying the medium access control in multi-hop wireless networks. The objective is to design practical MAC layer protocols for supporting multihop wireless networks. Particularly, we try to prolong the network lifetime without degrading performances with small battery-powered devices and improve the system throughput with poor quality channels. ^ In this dissertation, we design two MAC protocols. The first one is aimed at minimizing energy-consumption without deteriorating communication activities, which provides energy efficiency, latency guarantee, adaptability and scalability in one type of multi-hop wireless networks (i.e. wireless sensor network). Methodologically, inspired by the phase transition phenomena in distributed networks, we define the wake-up probability, which maintained by each node. By using this probability, we can control the number of wireless connectivity within a local area. More specifically, we can adaptively adjust the wake-up probability based on the local network conditions to reduce energy consumption without increasing transmission latency. The second one is a cooperative MAC layer protocol for multi-hop wireless networks, which leverages multi-rate capability by cooperative transmission among multiple neighboring nodes. Moreover, for bidirectional traffic, the network throughput can be further increased by using the network coding technique. It is a very helpful complement for current rate-adaptive MAC protocols under the poor channel conditions of direct link. Finally, we give an analytical model to analyze impacts of cooperative node on the system throughput. ^

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The exponential growth of studies on the biological response to ocean acidification over the last few decades has generated a large amount of data. To facilitate data comparison, a data compilation hosted at the data publisher PANGAEA was initiated in 2008 and is updated on a regular basis (doi:10.1594/PANGAEA.149999). By January 2015, a total of 581 data sets (over 4 000 000 data points) from 539 papers had been archived. Here we present the developments of this data compilation five years since its first description by Nisumaa et al. (2010). Most of study sites from which data archived are still in the Northern Hemisphere and the number of archived data from studies from the Southern Hemisphere and polar oceans are still relatively low. Data from 60 studies that investigated the response of a mix of organisms or natural communities were all added after 2010, indicating a welcomed shift from the study of individual organisms to communities and ecosystems. The initial imbalance of considerably more data archived on calcification and primary production than on other processes has improved. There is also a clear tendency towards more data archived from multifactorial studies after 2010. For easier and more effective access to ocean acidification data, the ocean acidification community is strongly encouraged to contribute to the data archiving effort, and help develop standard vocabularies describing the variables and define best practices for archiving ocean acidification data.

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This study is concerned with storytelling as a part of the folk culture of a fishing community on the north east coast of Newfoundland. The study is based on field work done in the community throughout the summer of 1969 during which I tape recorded oral narratives along with other folklore and folklife material . The principal genre discussed is the personal experience narrative which is an account of the experiences of either the narrator, someone in his kin network, orhis friends. It was found that a large number of community residents communicate in narrative form and that the narratives function to substantiate conversation preceeding the narrativei have a didactic function; function as a means of entertainment~ and reflect the narrators' and the community's value system. The methods employed in collecting the material were the directive and the non-directive interview techniques and participant observation. Collecting was done mainly among fishermen between fifty and eighty years of age and who, on -the average, had not gone beyond the sixth grade in school. Since the narratives are so much a part of the environment, I give an account of the community culture. The principal things that I deal with are the community's history, economy, education, religion, and social life which includes rites of passage, calendar customs , social events, visiting patterns, and gossip. Information in each of these categories is based primarily on oral reports, narratives and documented materials. After a discussion of the storytelling process in the community, I deal specifically with four male narrators. For each I give biographical information, discuss his repertoire, telling situations, style, and give a sampling of his narratives. The fourth narrator is discussed in more detail than the first three. The narratives of the latter comprise the final chapter in the study, and have been analyzed to show what they tell us about the narrator's style, his value system, and the community culture.

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During the "Polarstern"-expeditions ARK-IX/4 (1993) and ARK-XI/1 (1995), organised by the Alfred Wegener Institute (AWI), acoustic subbottom profiles (Parasound) have been collected in the Laptev Sea Shelf, Siberia. These data have been interpreted as an indicator of ice scours frequency and off-shore permafrost patterns. An additional acoustic profile data-base was available by the results of the expedition of the Federal Institute for Geosciences and Natural Resources (BGR) of the year 1994. The area of the expedition was located closer to the shelf, therefore supports a better understanding of ice scours frequency in shallower marine environments. The data-file consists of a 2930 km Parasound-traverse and has been subdivided into 586 working profiles. They are characterised by their location, number of ice scours, interpreted patterns of reflection and their extension and morphology. The data have been evaluated statistically and graphically and were presented in a map. Different patterns of sea floor reflection were established by different environments, outer influences (e.g. size of the icebergs, direction of the drift of icebergs) and the climatic history of the region. In the north-westerly region of the Laptev Sea at the continental slope of Severnaya Zemlya the sea floor in shallower depths has been ploughed intensely by recent icebergs. In some regions (40-60m), as an effect of intensely ploughing, the sea floor is hardly defined in acoustic profiles come along with relocation of marine deposits. Glacial diamiet deposits prevented the development of deep scours. Up to 355m deeper scours result from lower sea levels. The marginal north-easterly region of the Laptev Sea is characterised exclusively by this type of scour. Morphology and depth of these scours can be compared with those of the westerly Vilkitsky-Street so that similar conditions of development may be expected. Both, the north-easterly Laptev Sea and the Vilkitsky-Street, are not dominated by patterns ofrecent icebergs. In contrary the shelf-regions north-easterly ofthe Taimyr peninsula and north-westerly of the New Siberian Islands have been modified evidently by recent icebergs, which drifted with prevalent currents anticlockwise along the shelf edge of the Laptev Sea and cause the deepest scours of the whole region. The off-shore permafrost at the inner shelf regions has an important influence on the scours intensity. The permafrost layer can be recognised by the maximum depth of ice scours. It is represented by a Parasound reflector that can be made up for distances. The age of the ice scours cannot be determined absolutely by Parasound data but a relative order can be estimated whenever two scours are situated close to each other. When the Parasound-traverse ofthe expedition ARK-IX/4 (1993) (77°24'N 133°30'E-77°30'N 133°40'E) was repeated partially in expedition ARK-XI/l (1995) the ice scours of 1993 remained unchanged and uneroded and no new ice scours had been detected. It can be concluded that scours persist for a long time in the Laptev Sea, though after all with an average of 3 ice scours per kilometer there are not many at all in the Laptev Sea.

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As the world population continues to grow past seven billion people and global challenges continue to persist including resource availability, biodiversity loss, climate change and human well-being, a new science is required that can address the integrated nature of these challenges and the multiple scales on which they are manifest. Sustainability science has emerged to fill this role. In the fifteen years since it was first called for in the pages of Science, it has rapidly matured, however its place in the history of science and the way it is practiced today must be continually evaluated. In Part I, two chapters address this theoretical and practical grounding. Part II transitions to the applied practice of sustainability science in addressing the urban heat island (UHI) challenge wherein the climate of urban areas are warmer than their surrounding rural environs. The UHI has become increasingly important within the study of earth sciences given the increased focus on climate change and as the balance of humans now live in urban areas.

In Chapter 2 a novel contribution to the historical context of sustainability is argued. Sustainability as a concept characterizing the relationship between humans and nature emerged in the mid to late 20th century as a response to findings used to also characterize the Anthropocene. Emerging from the human-nature relationships that came before it, evidence is provided that suggests Sustainability was enabled by technology and a reorientation of world-view and is unique in its global boundary, systematic approach and ambition for both well being and the continued availability of resources and Earth system function. Sustainability is further an ambition that has wide appeal, making it one of the first normative concepts of the Anthropocene.

Despite its widespread emergence and adoption, sustainability science continues to suffer from definitional ambiguity within the academe. In Chapter 3, a review of efforts to provide direction and structure to the science reveals a continuum of approaches anchored at either end by differing visions of how the science interfaces with practice (solutions). At one end, basic science of societally defined problems informs decisions about possible solutions and their application. At the other end, applied research directly affects the options available to decision makers. While clear from the literature, survey data further suggests that the dichotomy does not appear to be as apparent in the minds of practitioners.

In Chapter 4, the UHI is first addressed at the synoptic, mesoscale. Urban climate is the most immediate manifestation of the warming global climate for the majority of people on earth. Nearly half of those people live in small to medium sized cities, an understudied scale in urban climate research. Widespread characterization would be useful to decision makers in planning and design. Using a multi-method approach, the mesoscale UHI in the study region is characterized and the secular trend over the last sixty years evaluated. Under isolated ideal conditions the findings indicate a UHI of 5.3 ± 0.97 °C to be present in the study area, the magnitude of which is growing over time.

Although urban heat islands (UHI) are well studied, there remain no panaceas for local scale mitigation and adaptation methods, therefore continued attention to characterization of the phenomenon in urban centers of different scales around the globe is required. In Chapter 5, a local scale analysis of the canopy layer and surface UHI in a medium sized city in North Carolina, USA is conducted using multiple methods including stationary urban sensors, mobile transects and remote sensing. Focusing on the ideal conditions for UHI development during an anticyclonic summer heat event, the study observes a range of UHI intensity depending on the method of observation: 8.7 °C from the stationary urban sensors; 6.9 °C from mobile transects; and, 2.2 °C from remote sensing. Additional attention is paid to the diurnal dynamics of the UHI and its correlation with vegetation indices, dewpoint and albedo. Evapotranspiration is shown to drive dynamics in the study region.

Finally, recognizing that a bridge must be established between the physical science community studying the Urban Heat Island (UHI) effect, and the planning community and decision makers implementing urban form and development policies, Chapter 6 evaluates multiple urban form characterization methods. Methods evaluated include local climate zones (LCZ), national land cover database (NCLD) classes and urban cluster analysis (UCA) to determine their utility in describing the distribution of the UHI based on three standard observation types 1) fixed urban temperature sensors, 2) mobile transects and, 3) remote sensing. Bivariate, regression and ANOVA tests are used to conduct the analyses. Findings indicate that the NLCD classes are best correlated to the UHI intensity and distribution in the study area. Further, while the UCA method is not useful directly, the variables included in the method are predictive based on regression analysis so the potential for better model design exists. Land cover variables including albedo, impervious surface fraction and pervious surface fraction are found to dominate the distribution of the UHI in the study area regardless of observation method.

Chapter 7 provides a summary of findings, and offers a brief analysis of their implications for both the scientific discourse generally, and the study area specifically. In general, the work undertaken does not achieve the full ambition of sustainability science, additional work is required to translate findings to practice and more fully evaluate adoption. The implications for planning and development in the local region are addressed in the context of a major light-rail infrastructure project including several systems level considerations like human health and development. Finally, several avenues for future work are outlined. Within the theoretical development of sustainability science, these pathways include more robust evaluations of the theoretical and actual practice. Within the UHI context, these include development of an integrated urban form characterization model, application of study methodology in other geographic areas and at different scales, and use of novel experimental methods including distributed sensor networks and citizen science.

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Flame retardants (FRs) are added to materials to enhance the fire safety level of readily combustible polymers. Although they have been purported to aid in preventing fires in some cases, they have also become a significant cause for concern given the vast data on environmental persistence and human and animal adverse health effects. Evidence since the 1980s has shown that Canadian, American and Europeans have detectable levels of FRs in their bodies. North Americans in particular have high levels of these chemicals due to stringent flammability standards and the higher use of polybrominated diphenyl ethers (PBDEs) in North America as opposed to Europe. FRs have been detected in household dust and some evidence suggests that TVs could be a significant source of exposure to FRs. It is imperative to re-visit the flammability standard (UL94V) that allows for FR use in TVs plastic materials by providing a risk versus benefit analysis to determine if this standard provides a fire safety benefit and if it plays a major role in FR exposure. This report first examined the history of televisions and the progression to the UL94V flammability test standard to understand why FRs were first added to polymers used in the manufacturing of TVs. It has been demonstrated to be due to fire hazards resulting from the use of plastic materials in cathode-ray tube (CRT) TVs that had an “instant-on” feature and high voltage and operating temperatures. In providing a risk versus benefit analysis, this paper presents the argument that 1) by providing a market survey the current flammability test standard (UL94V) is outdated and lacks relevance to current technology as flat, thin, energy efficient Liquid Crystal Displays (LCDs) dominate over traditionally used heavy, bulky and energy-intensive CRTs; 2) FRs do not impart fire safety benefits considering that there is a lack of valid fire safety concern, such as reduced internal and external ignition and fire hazard, and a lack of valid fire data and hazard for television fires in general and finally; 3) the standard is overly stringent as it does not consider the risk due to exposure to FRs in household dust due to the proliferation and greater use of televisions in households. Therefore, this report argues that the UL94V standard has become trapped in history and needs to be updated as it may play a major role in FR exposure.

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Model Driven Engineering uses the principle that code can automatically be generated from software models which would potentially save time and cost of development. By this methodology, a systems structure and behaviour can be expressed in more abstract, high level terms without some of the accidental complexity that the use of a general purpose language can bring. Models are the actual implementation of the system unlike in traditional software development where models are often used for documentation purposes only. However once the code is generated from the model, testing and debugging activities tend to happen on the code level and the model is not updated. We believe that monitoring on the model level could potentially facilitate quality assurance activities as the errors are detected in the early phase of development. In this thesis, we create a Monitoring Configuration for an open source model driven engineering tool called PapyrusRT in Eclipse. We support the run-time monitoring of UML-RT elements with a tracing tool called LTTng. We annotate the model with monitoring information to be used by the code generator for adding tracepoint statements for the corresponding elements. We provide the option of a timing specification to discover latency errors on the model. We validate the results by creating and tracing real time models in PapyrusRT.

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The endothelium is the inner most layer of cells that lines all arteries. A primary function of endothelial cells is to regulate responses to increased blood flow and the resulting frictional forces or shear stress by producing factors such as nitric oxide that mediate arterial dilation (flow mediated dilation (FMD)). Menstrual cycle variations in estrogen (E2) have been shown to influence brachial artery (BA) FMD in response to transient increases in shear stress brought about by the release of a brief forearm occlusion (reactive hyperemia (RH)). FMD can also be assessed in response to a sustained shear stress stimulus such as that created with handgrip exercise (HGEX), and studies have shown that RH- and HGEX stimulated FMD provide unique information regarding endothelial function. However, the impact of menstrual phase on HGEX-FMD is unknown. Therefore, the purpose of this study was to determine the impact of cyclical changes in E2 levels on HGEX-FMD over two discrete phases of the menstrual cycle. FMD was assessed via ultrasound. 12 subjects (21 ± 2yrs) completed two experimental visits: (1) low estrogen phase (early follicular) and (2) High estrogen phase (late follicular). In each visit both RH- and HGEX-FMD (6 min handgrip exercise) were assessed. Results are mean ± SD. E2 increased from the low to the high estrogen phase of the menstrual cycle (low: 34 ± 8, high: 161 ± 113pg/mL, p = 0.004). There was no change in mean FMD between phases (RH-FMD: 7.7 ± 4.3% vs. 6.4 ± 3.1%, p = 0.139; HGEX-FMD: 4.8 ± 2.8% vs. 4.8 ± 2.3%, p = 0.979). The observation that both RH- and HGEX-FMD did not differ between phases indicates that menstrual cycle fluctuations in estrogen may not universally impact endothelial function in young, healthy premenopausal women. Further research is needed to improve our understanding of the mechanisms that underlie variability in the impact of menstrual phase on both transient and sustained FMD responses.

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Executive functions (EF) such as self-monitoring, planning, and organizing are known to develop through childhood and adolescence. They are of potential importance for learning and school performance. Earlier research into the relation between EF and school performance did not provide clear results possibly because confounding factors such as educational track, boy-girl differences, and parental education were not taken into account. The present study therefore investigated the relation between executive function tests and school performance in a highly controlled sample of 173 healthy adolescents aged 12–18. Only students in the pre-university educational track were used and the performance of boys was compared to that of girls. Results showed that there was no relation between the report marks obtained and the performance on executive function tests, notably the Sorting Test and the Tower Test of the Delis-Kaplan Executive Functions System (D-KEFS). Likewise, no relation was found between the report marks and the scores on the Behavior Rating Inventory of Executive Function—Self-Report Version (BRIEF-SR) after these were controlled for grade, sex, and level of parental education. The findings indicate that executive functioning as measured with widely used instruments such as the BRIEF-SR does not predict school performance of adolescents in preuniversity education any better than a student's grade, sex, and level of parental education.

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The androgen receptor (AR) is expressed in 60-80% of breast cancers (BC) across all molecular phenotypes, with a higher incidence in oestrogen receptor positive (ER+) BC compared to ER negative tumours. In ER+ disease, AR-expression has been linked to endocrine resistance which might be reversed with combined treatment targeting ER and AR. In triple negative BCs (TNBC), preclinical and clinical investigations have described a subset of patients that express the AR and are sensitive to androgen blockade, providing a novel therapeutic target. Enzalutamide, a potent 2nd generation anti-androgen, has demonstrated substantial preclinical and clinical anti-tumour activity in AR+ breast cancer. Short-term preoperative window of opportunity studies are a validated strategy for novel treatments to provide proof-of-concept and define the most appropriate patient population by directly assessing treatment effects in tumour tissue before and after treatment. The ARB study aims to assess the anti-tumour effects of enzalutamide in early ER+ breast cancer and TNBC, to identify the optimal target population for further studies and to directly explore the biologic effects of enzalutamide on BC and stromal cells. Methods: ARB is an international, investigator sponsored WOO phase II study in women with newly diagnosed primary ER+ BC or AR+ TNBC of ≥ 1cm. The study has two cohorts. In the ER+ cohort, postmenopausal patients will be randomised 2:1 to receive either enzalutamide (160mg OD) plus exemestane (50mg OD) or exemestane (25mg OD). In the TNBC cohort, AR+ will receive single agent treatment with enzalutamide (160mg OD). Study treatment is planned for 15–29 days, followed by surgery or neo-adjuvant therapy. Tissue and blood samples are collected before treatment and on the last day of study treatment. The primary endpoint is inhibition of tumour-cell proliferation, as measured by change in Ki67 expression, determined centrally by 2 investigators. Secondary endpoints include induction of apoptosis (Caspase3), circulating hormone levels and safety. ARB aims to recruit ≈235 patients from ≈40 sites in the UK, Germany, Spain and USA. The study is open to recruitment.

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We present a comprehensive study based on first-principles calculations about the interplay of four important ingredients on the electronic structure of graphene: defects + magnetism + ripples + strain. So far they have not been taken into account simultaneously in a set of ab initio calculations. Furthermore, we focus on the strain dependence of the properties of carbon monovacancies, with special attention to magnetic spin moments. We demonstrated that such defects show a very rich structural and spin phase-diagram with many spin solutions as function of strain. At zero strain the vacancy shows a spin moment of 1.5 Bohrs that increases up to 2 Bohrs with stretching. Changes are more dramatic under compression: the vacancy becomes non-magnetic under a compression larger than 2%. This transition is linked to the structural modifications associated with the formation of ripples in the graphene layer. Our results suggest that such interplay could have important implications for the design of future spintronics devices based on graphene derivatives, as for example a spin-strain switch based on vacancies.

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Thesis (Ph.D.)--University of Washington, 2016-08

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Thesis (Ph.D.)--University of Washington, 2016-06