920 resultados para Reflection nebulae
Resumo:
We present assembly and application of an optical reflectometer for the analysis of dental erosion. The erosive procedure involved acid-induced softening and initial substance loss phases, which are considered to be difficult for visual diagnosis in a clinic. Change of the specular reflection signal showed the highest sensitivity for the detection of the early softening phase of erosion among tested methods. The exponential decrease of the specular reflection intensity with erosive duration was compared to the increase of enamel roughness. Surface roughness was measured by optical analysis, and the observed tendency was correlated with scanning electron microscopy images of eroded enamel. A high correlation between specular reflection intensity and measurement of enamel softening (r(2) ? -0.86) as well as calcium release (r(2) ? -0.86) was found during erosion progression. Measurement of diffuse reflection revealed higher tooth-to-tooth deviation in contrast to the analysis of specular reflection intensity and lower correlation with other applied methods (r(2) = 0.42-0.48). The proposed optical method allows simple and fast surface analysis and could be used for further optimization and construction of the first noncontact and cost-effective diagnostic tool for early erosion assessment in vivo.
Evaluation of perpendicular reflection intensity for assessment of caries lesion activity/inactivity
Resumo:
The aim of this study was to evaluate, using visual assessment, an experimental optical sensor measuring perpendicular reflection intensity (PRI) as an indicator of enamel caries lesion activity/inactivity. Forty teeth with either an active or an inactive enamel lesion were selected from a pool of extracted teeth. Each tooth was cut into halves, with a clinically sound half and a half with a non-cavitated enamel lesion. After gentle plaque removal, the teeth were kept moistened. The lesions were then photographed and a defined measuring site per lesion was chosen and indicated with an arrow on a printout. Independently, the chosen site was visually assessed for lesion activity, and its glossiness was measured with PRI assessment. Surface roughness (SR) was assessed with optical profilometry using a confocal microscope. Visual assessment and PRI were repeated after several weeks and a reliability analysis was performed. For enamel lesions visually scored as active versus inactive, significantly different values were obtained with both PRI and SR. PRI values of the clinically sound control surfaces were significantly different only from active lesions. Generally, inactive lesions had the same glossiness and the same roughness as the sound control surfaces. The reliabilities for visual assessment (? = 0.89) and for PRI (ICC = 0.86) were high. It is concluded that, within the limits of this study, PRI can be regarded as a promising tool for quantitative enamel lesion activity assessment. There is scope and potential for the PRI device to be considerably improved for in vivo use.
Resumo:
To support development tools like debuggers, runtime systems need to provide a meta-programming interface to alter their semantics and access internal data. Reflective capabilities are typically fixed by the Virtual Machine (VM). Unanticipated reflective features must either be simulated by complex program transformations, or they require the development of a specially tailored VM. We propose a novel approach to behavioral reflection that eliminates the barrier between applications and the VM by manipulating an explicit tower of first-class interpreters. Pinocchio is a proof-of-concept implementation of our approach which enables radical changes to the interpretation of programs by explicitly instantiating subclasses of the base interpreter. We illustrate the design of Pinocchio through non-trivial examples that extend runtime semantics to support debugging, parallel debugging, and back-in-time object-flow debugging. Although performance is not yet addressed, we also discuss numerous opportunities for optimization, which we believe will lead to a practical approach to behavioral reflection.
Resumo:
A successful actor often requires a specific acting method or style to enhance their performance. Through theatrical research, rehearsal and performance, an actor can narrow down their seemingly endless search for the most productive methodology. By researching, studying, and applying the methods of Constantin Stanislavski, Stella Adler,and Tadashi Suzuki to my rehearsal process, I have found my most effective acting style: Stella Adler?s method. I utilize this acting method during the performance period of my early professional acting career. Experimental research for this thesis was completed inthe studio. I applied each of the three aforementioned methods to a dramatic/classical monologue. The results I gathered helped me to decide upon Adler?s methodology to carry with me through my upcoming professional auditions and career. From casting resulting from the auditions, I will employ the methodology to my professional work asan actress. Each acting teacher has provided the performance world with a new way to experience their stage time. The methods are unique and enable the actor to find the most dynamic performance through engaging technical skill.
Resumo:
Publishing is an essential means of validation and communication of research. This is no different in transdisciplinary research, where publishing also aims at contributing to the development of society through sharing of knowledge. In the scientific world, authors need to disseminate and validate results, reflect on issues, and participate in debates. On the other hand, institutions and individuals are assessed according to their publication record – as probably the most influential of all current evaluation criteria. Occupying the space between article production and counting impact factors, journal editors and reviewers play an important role in defining and using rules to assess and improve the work submitted to them. Publishing transdisciplinary research poses specific challenges, in particular with regard to peer-review processes, as it addresses different knowledge communities with different value systems and purposes.
Resumo:
Higgins School of the Humanities/Difficult Dialogues: Video Recording from 11/16/2011 event featuring Cynthia Enloe and Frederick Luis Aldama titled "Inquiry and Reflection" Event Description: Freedom of inquiry (and the possibilities for discovery, insight and expanding knowledge that can flow from it) is fundamental to the experience of learning. Yet rarely do we pause to ask about inquiry itself, and to consider its practices. How do we best encourage authentic inquiry, in ourselves and in our students? To what do we give our attention, and why? What promotes the possibility of new discoveries and insights? Our guests for a conversation on inquiry are Frederick Luis Aldama of Ohio State University, a prolific scholar of wide-ranging interests, and Cynthia Enloe, research professor at Clark University, whose work is characterized by her subtle and provocative curiosity, and the asking of good questions.
Resumo:
Along a downstream stretch of River Mure , Romania, adult males of two feral fish species, European chub (Leuciscus cephalus) and sneep (Chondrostoma nasus) were sampled at four sites with different levels of contamination. Fish were analysed for the biochemical markers hsp70 (in liver and gills) and hepatic EROD activity, as well as several biometrical parameters (age, length, wet weight, condition factor). None of the biochemical markers correlated with any biometrical parameter, thus biomarker reactions were related to site-specific criteria. While the hepatic hsp70 level did not differ among the sites, significant elevation of the hsp70 level in the gills revealed proteotoxic damage in chub at the most upstream site, where we recorded the highest heavy metal contamination of the investigated stretch, and in both chub and sneep at the site right downstream of the city of Arad. In both species, significantly elevated hepatic EROD activity downstream of Arad indicated that fish from these sites are also exposed to organic chemicals. The results were indicative of impaired fish health at least at three of the four investigated sites. The approach to relate biomarker responses to analytical data on pollution was shown to fit well the recent EU demands on further enhanced efforts in the monitoring of Romanian water quality.
Resumo:
This dissertation examines the global technological and environmental history of copper smelting and the conflict that developed between historic preservation and environmental remediation at major copper smelting sites in the United States after their productive periods ended. Part I of the dissertation is a synthetic overview of the history of copper smelting and its environmental impact. After reviewing the basic metallurgy of copper ores, the dissertation contains successive chapters on the history of copper smelting to 1640, culminating in the so-called German, or Continental, processing system; on the emergence of the rival Welsh system during the British industrial revolution; and on the growth of American dominance in copper production the late 19th and early 20th centuries. The latter chapter focuses, in particular, on three of the most important early American copper districts: Michigan’s Keweenaw Peninsula, Tennessee’s Copper Basin, and Butte-Anaconda, Montana. As these three districts went into decline and ultimately out of production, they left a rich industrial heritage and significant waste and pollution problems generated by increasingly more sophisticated technologies capable of commercially processing steadily growing volumes of decreasingly rich ores. Part II of the dissertation looks at the conflict between historic preservation and environmental remediation that emerged locally and nationally in copper districts as they went into decline and eventually ceased production. Locally, former copper mining communities often split between those who wished to commemorate a region’s past importance and develop heritage tourism, and local developers who wished to clear up and clean out old industrial sites for other purposes. Nationally, Congress passed laws in the 1960s and 1970s mandating the preservation of historical resources (National Historic Preservation Act) and laws mandating the cleanup of contaminated landscapes (CERCLA, or Superfund), objectives sometimes in conflict – especially in the case of copper smelting sites. The dissertation devotes individual chapters to the conflicts that developed between environmental remediation, particularly involving the Environmental Protection Agency and the heritage movement in the Tennessee, Montana, and Michigan copper districts. A concluding chapter provides a broad model to illustrate the relationship between industrial decline, federal environmental remediation activities, and the growth of heritage consciousness in former copper mining and smelting areas, analyzes why the outcome varied in the three areas, and suggests methods for dealing with heritage-remediation issues to minimize conflict and maximize heritage preservation.