Effects of saliva and nasal secretion on some physical properties of four different resin materials

Objective: Aim of this study was to evaluate possible effects of saliva and nasal secretion on some physical properties, such as sorption, solubility, surface hardness and colour change on four different resin-based materials over a certain time period. Materials and Methods: A total of 128 disc-shaped specimens with a diameter of 50mm and thickness of 0.5mm were tested to evaluate sorption and solubility (ISO-1567). The specimens were stored in different solutions prior to testing. Surface hardness measurements were performed by using a Vickers hardness testing machine. A total of 20 cylindershaped test specimens with a diameter of 13 mm and thickness of 1 mm were prepared to evaluate colour change (?E). Analysis of variance was used to determine significant differences among groups. Paired t and Tukey Post-Hoc tests were performed to investigate significant differences among subgroups at all time intervals (p<0.05). Results: It was found that while the percentage absorption value at T7(7 days) of the auto-polymerizing (A) groups storaged in artificial saliva + nasal secretion were the highest (0.057±0.119), the percentage absorption value at T15(15 days) of the D groups storaged in artificial nasal secretion were the lowest (0.013±0.09). Besides, it was found that the percentage solubility value at T30(30 days) of visible ligth-cusing resin (VLC) groups storaged in artificial nasal secretion were the highest (0.016±0.003), and the percentage solubility value at T1(1 day) of the D groups storaged in distilled water were the lowest (0.01±0.02). While the highest hardness value was of T0(Dry) in group heat-polymerizing (H) (36.19±1.35), the lowest hardness value was of T0 in group D (9.83±2.48). When ?E values analysed for each group, VLC group showed the highest values (23.78±5.05) (p<0.05), group D showed the lowest values (9.06±2.82) in time (between the T0 and T30). Conclusion: The new polyamide resin was observed to show better physical properties when compared with other materials

Determination of illness cognition levels in patients with maxillofacial area defects

The aim of this study was to measure the illness cognition of patients with defect in the maxillofacial region. Eighty patients participated in this study. Written informed consent was obtained from patients with maxillofacial area defect, and the patients were filled in with the guidance of the researchers. Illness Cognition Questionnaire (ICQ), forms measuring the illness awareness of the patients were completed.  The study was conducted independently of demographic characteristics. The statistical software SPSS (Statistical Package for Social Sciences, Version 20, Chicago IL, USA) was used for calculations. At the end of the study, ICQ scores in patients with maxillofacial defect were as follows: There was a statistically significant intra class correlation of 88.6% (0.843-0.942) among the Helplessness scale scores of the participants. There was a statistically significant intra class correlation of 80.3% (0.728-0.863) among the Acceptance scale scores of the participants. There was a statistically significant intra class correlation of 0.752 % (0,657-0,827) among the Perceived benefits scale scores of the participants. Patients with maxillofacial defects will focus on the disease cognition "Helplessness" category. In patients with relationship maxillofacial defect, the rate of helplessness (88.6%) was higher than acceptance (80.3%) and perceived benefit (0,752 %)

Uncertainty behind the veil of ignorance

This paper argues that the decision problem in the original position should be characterized as a decision problem under uncertainty even when it is assumed that the denizens of the original position know that they have an equal chance of ending up in any given individual's place. It argues for this claim by arguing that (a) the continuity axiom of decision theory does not hold between all of the outcomes the denizens of the original position face and that (b) neither us nor the denizens of the original position can know the exact point where discontinuity sets in, because the language we employ in comparing different outcomes is ineradicably vague. It is also argued that the account underlying (b) can help proponents of superiority in value theory defend their view against arguments offered by Norcross and Griffin

A country in a school: FAJR Iranian school in Turkey

The Fajr Iranian School has been located in Sultanahmet, in the center of Istanbul, for more than one hundred years, and it has operated as a foreign school continuously since 1882, providing education for the Iranian community in Istanbul. After the Islamic Revolution of 1979 in Iran, the Fajr Iranian School has become affiliated with the Embassy of the Islamic Republic of Iran (IRI) in Turkey. This special position of the school, as a government-run school of the Iranian regime located in a foreign country, implies the significance of this school’s spatial setting. This thesis is an ethnographic exploration into this spatiality. After presenting a brief history of this educational institution and the Iranian community in Turkey, this thesis argues that the spatial setting of the Fajr Iranian School, examined as an ideological state apparatus that creates a state-centered habitus, plays a significant role in constructing social identities of the Iranian students in Turkey. Furthermore, it shows that these students negotiate their identities differently based on their selfpositionings, which are examined through their collective and personal negotiations. On the one hand, the Fajr Iranian School plays a vital role in creating a ‘safe’ and ‘private’ space for its students to learn and maintain the culture, history and language around being Iranian in Turkey; on the other hand, it also constitutes a site of struggle due to being a ’closed place’ where the symbolic power of the state is differently exercised over its agents as the school aims to exert a dominant Iranian identity. Collective negotiations represent how the students negotiate their identities through a collective group lens. Personal negotiations, however, somehow as counter examples against the image of group identity, prove to be valuable to analyze that there are different positionings of some students in their interpersonal relations within this state-centered habitus. In this way, the thesis shows that, symbolic capitals and levels of symbolic power are prone to shifts for particular groups in the school space

The Epistemic Basic Structure

The epistemic basic structure of a society consists of those institutions that have the greatest impact on individuals’ opportunity to obtain knowledge on questions they have an interest in as citizens, individuals, and public officials. It plays a central role in the production and dissemination of knowledge and in ensuring that people have the capability to assimilate this knowledge. It includes institutions of science and education, the media, search engines, libraries, museums, think tanks, and various government agencies. This article identifies two demands of justice that apply specifically to the institutions that belong to it. First, the epistemic basic structure should serve all citizens fairly and reliably. It should provide them with the opportunity to acquire knowledge they need for their deliberations about the common good, their individual good, and how to pursue them. Second, the epistemic basic structure should produce and disseminate the knowledge that various experts and public officials need to successfully pursue justice and citizens need to effectively exercise their rights. After arguing for these duties, I discuss what policies follow from them and respond to the worry that these duties have illiberal implications

The Democratization of Science

The democratization of science entails the public having greater influence over science and that influence being shared more equally among members of the public. This chapter will present a thumbnail sketch of the arguments for the democratization of science based on the importance of collectively shaping science’s impact on society, the instrumental benefits of public participation in science, and the need to ensure that the use of science in politics does not undermine collective self-government. It will then outline worries about citizen competence, the abuse of democratic ideals and the limits posed by the nation-state

Tekrarlanan döküm işleminin dental alaşımların mekanik özelliklerine etkisi

In the dental laboratories, surplus alloys are commonly reused from the initial casting, and with the addition of new alloy, produces other restorations. Recasting may change the chemical composition and microstructure of alloys and thus have an effect on the change of mechanical properties. The results about this subject have indicated that the amounts of the elements, especially Cu, Sn, Zn, Cr and Ti, were decreased; the grain size was increased; the casting defects, principally porosities, and the impurity contents were increased, and the mechanical properties were affected. Since particular metal oxides are critical for adequate adhesion of dental porcelain to metal structure, it is possible that repeated casting of metals could also be detrimental for metal-ceramic bonding. The optimal proportions of new and old alloys are not well known and the effect of reusing dental alloys on mechanical properties has not been completely understood. Before a definitive recommendation can be made for repeatedly using dental alloys, clinically relevant mechanical properties and bond strength of porcelain-to-metal for different alloy systems should be evaluated and considered along with compositional-microstructural analyses and biological properties of the remelted alloys. In this review article, the effects of recasting on mechanical properties of dental alloys and current issues relevant to these properties of recast alloys were presented. ÖZET Dental laboratuvarlarda, ilk dökümden artan alaşımlar sıklıkla yeniden kullanılmakta ve yeni alaşım ilavesi ile başka restorasyonlar oluşturulmaktadır. Tekrarlanan döküm işlemi, alaşımın kimyasal bileşimini ve mikroyapısını değiştirebilir ve böylece mekanik özelliklerini etkileyebilir. Bu konuya ilişkin çalışma sonuçları özellikle Cu, Sn, Zn, Cr ve Ti miktarlarının azaldığına, tane boyutunun büyüdüğüne, özellikle poroziteler olmak üzere döküm defektlerinin ve kirliliklerin arttığına işaret etmiştir. Dental porselenin metal yapıya yeterli adezyonunda spesifik metal oksitleri önemli olduğu için, tekrarlanan döküm işleminin metal-porselen bağlantısı için de zararlı olması mümkündür. Yeni ve eski alaşımın optimal karıştırılma oranları tam olarak netleşmemiştir ve artık alaşımların mekanik özellikler üzerindeki etkisi tam olarak bilinmemektedir. Dental alaşımların tekrarlanan kullanımı için beyanda bulunulmadan önce, klinik bağlantılı mekanik özellikleri ve farklı alaşım sistemleri için metal-porselen bağlanma direnci incelenmeli ve bulgular, artık alaşımların bileşim- mikroyapı analizleri ve biyolojik özellikleri ile birlikte değerlendirilmelidir. Bu makalede, tekrarlanan dökümün dental alaşımların mekanik özellikleri üzerindeki etkileri ve artık alaşımların mekanik özelliklerini inceleyen çalışmalar değerlendirilmiştir. Anahtar kelimeler: Bileşim, dental döküm alaşımları, mekanik özellikler, mikroyapı, tekrarlanan dökü

Well-ordered science and public trust in science

Building, restoring and maintaining well-placed trust between scientists and the public is a difficult yet crucial social task requiring the successful cooperation of various social actors and institutions. Kitcher’s (Science in a democratic society, Prometheus Books, Amherst, 2011) takes up this challenge in the context of liberal democratic societies by extending his ideal model of “well-ordered science” that he had originally formulated in his (Science, truth, and democracy, Oxford University Press, Oxford, 2001). However, Kitcher nowhere offers an explicit account of what it means for the public to invest epistemic trust in science. Yet in order to understand how his extended model and its implementation in the actual world address the problem of trust as well as to evaluate it critically, an explicit account of epistemic public trust in science needs to be given first. In this article we first present such an account and then scrutinize his project of building public trust in science in light of it. We argue that even though Kitcher’s ideal model and his proposals for its implementation in the real world face a number of problems, they can be addressed with the resources of our account