Effect of ultraviolet photofunctionalization of dental titanium implants on osseointegration

Objective

The aim of the current study was to evaluate the effect of ultraviolet (UV) photofunctionalization of dental titanium implants with exposure to the oral cavity on osseointegration in an animal model.

Methods

Forty-eight titanium implants (Camlog® Conelog® 4.3 mmx9.0 mm) were placed epicrestally into the edentulous jaws of three minipigs and implant stability was assessed by measuring the implant stability quotient (ISQ). Prior to implantation half of the implants were photofunctionalized with intense UV-light. After three months, the implants were exposed and ISQ was measured again. After six months of implant exposure, the minipigs were sacrificed and the harvested specimens were analyzed using histomorphometric, light, and fluorescence microscopy.

Main results

Forty-two of 48 implants osseointegrated. The overall mean bone-implant contact area (BIC) was (64±22)%. No significant differences were found in BIC or ISQ value (multivariate analysis of variance (MANOVA), P>0.05) between implants with and without exposure to UV photofunctionalization.

Conclusions

No significant effects were observed on osseointegration of dental titanium implants nine months after exposure of UV photofunctionalization.

     

Experiencing Exhibitions: A Review of Studies on Visitor Experiences in Museums

Abstract This article reviews empirically oriented studies from the United States and Europe concerning visitor experiences in museum exhibitions in order to pinpoint similarities and differences among them. In the last 20 years, only a few scholars have tackled this research question in multifaceted empirical ways, although some of them have done so extensively. By comparing theoretical and methodical issues, as well as important results, we are able to outline several analytical building blocks that compose a complex framework of visitor expectations, experiences, and outcomes. Gathering credible data on experiences of visitors in exhibitions or museums, a method dating back to the tracking records of Robinson (1928) , is an ongoing challenge for the empirically inclined science of museum studies. Social scientists at universities and museums have been asking for 20 years: What are the findings regarding factors, structures, and consequences of exhibition experiences? Where are the blind spots? Which questions should be researched?     

The Red Jacket UTB: a model for co‐operative textbook publishing

UTB is a joint paperback imprint of a number of medium‐sized German publishers. Its working is described, together with its financial arrangements.     

Inquiry-Based Learning and the Art of Mathematical Discourse

Abstract

Our particular flavor of inquiry-based learning (IBL) uses mathematical discourse, conversations, and discussions to empower students to deepen their mathematical thinking, building on strengths of students in the humanities. We present an organized catalog of powerful questions, discussion prompts, and talk moves that can help faculty facilitate a classroom focused on mathematical discourse. The paper brings this discourse alive through classroom vignettes and explores various teacher moves and their impacts. The mathematical theme of the classroom investigations, Maypole dance patterns, stems from the learning guide “Discovering the Art of Mathematics: Dance.” Both authors are part of the NSF-funded project “Discovering the Art of Mathematics,” which provides IBL materials for mathematics for liberal arts courses, see www.artofmathematics.org.     

Bildung und Popmusik

Die Bedeutung von Popmusik im Leben von Jugendlichen und jungen Erwachsenen wird meist nur im Hinblick auf ihre alltagspraktische Funktion oder den Gebrauch thematisiert, der von ihr gemacht wird. Ausgehend von einigen Anregungen aus ?sthetik, Biographieforschung und Bildungstheorie soll dagegen im vorliegenden Beitrag versucht werden, diese Sichtweise durch die Einbeziehung der Musik selbst auf eine Weise zu erweitern, die es erlaubt, die Auseinandersetzung mit Popmusik als ?sthetische Erfahrung ernst zu nehmen und damit auch die Frage nach ihrem m?glichen Bildungssinn neu zu stellen. Anhand einiger Beispiele aus einer Schreibwerkstatt, in der junge Erwachsene sich erinnernd mit ihren popmusikalischen Erfahrungen auseinander gesetzt haben, wird gezeigt, wie im je spezifischen Zusammenwirken von lebensgeschichtlichem Kontext, dem besonderem musikalischen Material und den Erfahrungen, die damit gemacht werden, neue Sinnschichten und Bedeutungen performativ hervorgebracht werden, die weder als „Ausdruck“ der jeweiligen Situation noch als blo?e „Projektionen“ von momentanen Stimmungen auf ein für sich genommen bedeutungsloses Klanggebilde verstanden werden k?nnen. Ihre Bedeutung für Bildungsprozesse erschlie?t sich freilich erst, wenn eher vom rezeptiven als vom souver?nen Selbst, eher von dem Leben, das wir leben, als von dem, das wir „führen“, ausgegangen wird.     

A faculty team works to create content linkages among various courses to increase meaningful learning of targeted concepts of microbiology

As research faculty with expertise in the area of host–pathogen interactions (HPI), we used a research group model to effect our professional development as scientific educators. We have established a working hypothesis: The implementation of a curriculum that forms bridges between our seven HPI courses allows our students to achieve deep and meaningful learning of HPI concepts. Working collaboratively, we identified common learning goals, and we chose two microorganisms to serve as anchors for student learning. We instituted variations of published active-learning methods to engage students in research-oriented learning. In parallel, we are developing an assessment tool. The value of this work is in the development of a teaching model that successfully allowed faculty who already work collaboratively in the research area of HPI to apply a “research group approach” to further scientific teaching initiatives at a research university. We achieved results that could not be accomplished by even the most dedicated instructor working in isolation.     

Developmental changes in item and source memory: evidence from an ERP recognition memory study with children, adolescents, and adults

Event-related potential (ERP) correlates of item and source memory were assessed in 18 children (7-8 years), 20 adolescents (13-14 years), and 20 adults (20-29 years) performing a continuous recognition memory task with object and nonobject stimuli. Memory performance increased with age and was particularly low for source memory in children. The ERP difference between first presentations of objects and nonobjects, reflecting generic novelty processing, showed only small developmental changes. Regarding item memory, adults showed the putative ERP correlates of familiarity and recollection, whereas ERP effects in children and adolescents suggested a strong reliance on recollection. ERP correlates of source memory refined with age, suggesting maturation of strategic recollection between childhood and adolescence and the development of postretrieval control until adulthood.     

Modelling the deflection of rowing oar shafts

The deflection of rowing oar shafts subjected to a static load was investigated. Two sets of sculling oars of different design stiffness were tested at three different lengths from 2.66 to 2.70 m. Loads up to 201 N were applied to the blade end of the oar shafts, and deflections were measured at six positions along the length of the shafts. The experimental results were compared with theoretical predictions obtained by modelling the oar shafts as homogenous end-loaded cantilever beams. The results show that the oar shafts are not uniform, in contradiction to the assumed model, but rather are most compliant near the sleeves and up to 80% stiffer towards the blades. The effect of oar shaft stiffness and length on the deflection angle at the blade end of the oar shaft was at most 1.18 ± 0.01°. The measured variation of stiffness along the shaft has implications for boat propulsion and rowing performance.