Effects of surface treatments on the shear bond strength of luting cements to zirconia

Objective: The aim of this in vitro study was to evaluate the effect of surface treatments on the shear bond strength of resin cements to zirconia. Material and methods: Sintered zirconia specimens (n = 192) were divided into four different surface treatment groups: control (no treatment); airborne-particle abrasion; glaze layer and hydrofluoric acid (HF) application, and hot etching solution application. Then, each group was divided into four subgroups (n = 12), and three different resin cements were applied to the zirconia surfaces. The shear bond strength value of each specimen was measured after 5000 thermo cycles. The failure types were examined with a stereomicroscope and the effects of the surface treatments were evaluated with a scanning electron microscope. Results were analyzed using analysis of variance and Tukey’s post hoc tests (α = 0.05). Results: The surface treatment and resin cement type significantly affected the bond strength results (p < 0.05). For all resin cements, the airborne-particle abrasion treatment increased the shear bond strength values (p < 0.05). The glaze layer & HF application increased shear bond strength values for all groups, except the Single Bond Universal-RelyX Unicem Aplicap group (p < 0.05). The surface roughness values of airborne-particle abraded specimens were similar to comparable values for specimens from the control group and the hot etching solution group (p > 0.05). The glaze layer & HF application group produced the highest surface roughness values (p < 0.05). Conclusion: The results of this study recommend using the appropriate combination of surface treatment and adhesive/silane coupling agent to achieve durable zirconia-resin bonding.     

Synthesis,Biochemistry, and Computational Studies of Brominated Thienyl Chalcones: A New Class of Reversible MAO‐B Inhibitors

A series of (2E)‐1‐(5‐bromothiophen‐2‐yl)‐3‐(para‐substituted phenyl)prop‐2‐en‐1‐ones ( TB1 – TB11 ) was synthesized and tested for inhibitory activity toward human monoamine oxidase (hMAO). All compounds were found to be competitive, selective, and reversible toward hMAO‐B except (2E)‐1‐(5‐bromothiophen‐2‐yl)‐3‐(4‐nitrophenyl)prop‐2‐en‐1‐one ( TB7 ) and (2E)‐1‐(5‐bromothiophen‐2‐yl)‐3‐(4‐chlorophenyl)prop‐2‐en‐1‐one ( TB8 ), which were selective inhibitors of hMAO‐A. The most potent compound, (2E)‐1‐(5‐bromothiophen‐2‐yl)‐3‐[4‐(dimethylamino)phenyl]prop‐2‐en‐1‐one ( TB5 ), showed the best inhibitory activity and higher selectivity toward hMAO‐B, with K_i and SI values of 0.11±0.01 μm and 13.18, respectively. PAMPA assays for all compounds were carried out in order to evaluate the capacity of the compounds to cross the blood–brain barrier. Moreover, the most potent MAO‐B inhibitor, TB5 , was found to be nontoxic at 5 and 25 μm , with 95.75 and 84.59 % viability among cells, respectively. Molecular docking simulations were carried out to understand the crucial interactions responsible for selectivity and potency.     

An ontology-based support for product conceptual design

The research presented in this paper is a follow-up of our prior work involving the development of a graphical modeling tool to support designers at the conceptual design stage. To close the loop for supporting designers in generating design concepts flexibly, fast, and easily, an ontology-based approach for knowledge management that works along with the graphical modeling tool is discussed. Ontology and databases for the tool are developed to promote the systematic capture of design knowledge and efficient reuse of the design knowledge selection. In order to locate the proper information and query the data from the databases, the relationship between the ontology and databases, the data analysis process, ontology enrichment, and the ontology-based query engine are built to offer users multiple design results according to users’ requirements. A tire design example is presented to demonstrate the proposed approach. The ontology-based method described in this paper can help retrieve and save the complex relations, support the reasoning, integrate heterogeneous data resources and offer users more accurate, proper and comprehensive data.     

Concept design of future intelligent Earth observing satellites

This paper presents a concept design of an envisioned future intelligent Earth observing satellite (FIEOS) system. The proposed system is a space-based architecture for the dynamic and comprehensive on-board integration of Earth observing sensors, data processors and communication systems. The architecture and implementation strategies suggest a seamless integration of diverse components into a smart, adaptable and robust Earth observation satellite system. It is intended to enable simultaneous, global measurements and timely analyses of the Earth's environment for a variety of users. In particular, common users would directly access data in a manner similar to selecting a TV channel. We also discuss key technology problems, current technology development, amongst other things. It is concluded that (1) the proposed intelligent Earth observing satellite system is technically feasible; and (2) information technology and real-time information systems, for example multi-layer satellite networks connected with an organic system and on-board data processor capabilities, are crucial for implementation of the intelligent system. This revolutionary concept should dramatically impact on how Earth observing systems develop and conduct missions in the future.     

Eliciting positive user experiences with self-service kiosks: pursuing possibilities

Although the prominent concept of the last decade – user experience – maintains its significance in diverse disciplines, especially design, its focus has changed to eliciting positive user experiences by pursuing new possibilities for consumer products rather than by solely seeking solutions to existing problems. Designers continue to aim for rich user experiences with a variety of products, but have neglected self-service (interactive) kiosks. Hence, this paper, after giving a brief overview of the positive psychology literature, demonstrates the dimensions of positive user experiences with self-service kiosks through an empirical study conducted on coffee vending machines and automated tellers.     

Field-based crop classification using SPOT4, SPOT5, IKONOS and QuickBird imagery for agricultural areas: a comparison study

A comparison of agricultural crop maps from independent field-based classifications of the Satellite Pour l'Observation de la Terre (SPOT) 4 multispectral (XS), SPOT5 XS, IKONOS XS, QuickBird XS and QuickBird pan-sharpened (PS) images is presented. An agricultural area within the north-west section of Turkey was analysed for field-based crop identification. The SPOT4 XS, SPOT5 XS, IKONOS XS and QuickBird images were collected in similar climatic conditions during July and August 2004. The classification of each image was carried out separately on a per-field basis on all bands and the coincident bands that are green, red and near-infrared (NIR). To examine the effect of filtering on field-based classification, the images were each filtered using the 3?×?3, 5?×?5, 7?×?7 and 9?×?9 mean filter and the filtered bands were also classified on per-field basis. For the unfiltered images, IKONOS XS provided the highest overall accuracies of 88.9% and 88.1% for the all-bands and the coincident bands classifications, respectively. On average, IKONOS XS performed slightly better than QuickBird XS and QuickBird PS, while it outperformed SPOT4 XS and SPOT5 XS. The use of filtered images in field-based classification reduced the accuracies for SPOT4 XS, SPOT5 XS, IKONOS XS and QuickBird XS. The results of this study indicate that smoothing images prior to classification does not improve the accuracies for the field-based classification. On the contrary, the accuracies for the filtered QuickBird PS images indicated a slight improvement. On the whole, both IKONOS and QuickBird images produced quite promising results for field-based crop mapping, yielding overall accuracies above 83%.     

Escherichia coli, enterococci, and Bacteroides thetaiotaomicron qPCR signals through wastewater and septage treatment

Fecal indicators such as Escherichia coli and enterococci are used as regulatory tools to monitor water with 24 h cultivation techniques for possible input of sewage or feces and presence of potential enteric pathogens yet their source (human or animal) cannot be determined with routine methods. This critical uncertainty has furthered water pollution science toward new molecular approaches. Members of Bacteroides genus, such as Bacteroides thetaiotaomicron are found to have features that allow their use as alternative fecal indicators and for Microbial Source Tracking (MST). The overall aim of this study was to evaluate the concentration and fate of B. thetaiotaomicron, throughout a wastewater treatment facility and septage treatment facility. A large number of samples were collected and tested for E. coli and enterococci by both cultivation and qPCR assays. B. thetaiotaomicron qPCR equivalent cells (mean: 1.8 × 10⁷/100 mL) were present in significantly higher concentrations than E. coli or enterococci in raw sewage and at the same levels in raw septage. The removal of B. thetaiotaomicron target qPCR signals was similar to E. coli and enterococci DNA during the treatment of these wastes and ranged from 3 to 5 log₁₀ for wastewater and was 7 log₁₀ for the septage. A significant correlation was found between B. thetaiotaomicron marker and each of the conventional indicators throughout the waste treatment process for both raw sewage and septage. A greater variability was found with enterococci when compared to E. coli, and CFU and equivalent cells could be contrasted by various treatment processes to examine removal and inactivation via septage and wastewater treatment. These results are compared and contrasted with other qPCR studies and other targets in wastewater samples providing a view of DNA targets in such environments.     

Acrytonitrile block copolymers

Summary Acrylonitrile was polymerized by an insertion process on being added to solutions containing the adduct of the reaction of tetrakis(dimethylamino) titanium (T4) and azobisisobutyronitrile (AIBN). The obtained azo-linked polyacrylonitrile has appropriate initiating functionality for a subsequent vinyl polymerization.