The effects of water flow rate on shear bond strength of self etch resin cement to dentin surface after Er,Cr:YSGG laser etching

The aim of the present study was to evaluate the effect of water flow rate on the morphological features of dentin and shear bond strength (SBS) of self-etching resin cement after Er,Cr:YSGG laser etching. Dentin specimens obtained from extracted human third molars were randomly assigned to four groups (n = 23), including one that received no laser irradiation (control-group D) and three others with different laser parameters: 2.25 W, 50 Hz, 60% air with water flow rates of 19 mL/min-100% water (group A), 2.25 W, 50 Hz, 6.75 mL/min-50% water (group B), and 2.25 W, and 50 Hz, 2.75 mL/min-25% water (group C). The morphological features of each group were examined with scanning electron microscopy and atomic force microscopy. The SBS of resin cement disks (Panavia F2.0, Kuraray; Tokyo, Japan) (3 mm in diameter and 2 mm in height) to the dentin specimens was measured using a universal testing machine at a cross head speed of 0.5 mm/min. Bond strength values were analyzed with one-way ANOVA/Tukey tests. There were no significant differences between the SBS values of groups A and B (p > 0.05). However, the SBS values of these groups were significantly higher when compared to groups C and D (p < 0.001). Er,Cr:YSGG laser application with water flow rates of 6.75 or 19 mL/min resulted in better dentin surface alterations and increased the SBS of self-etching resin cement to dentin.     

Performance of Silicotungstic Acid Incorporated Mesoporous Catalyst in Direct Synthesis of Dimethyl Ether from Syngas in the Presence and Absence of CO2

Dimethyl ether (DME), which is an excellent green diesel fuel alternate, is synthesized following a direct synthesis route from synthesis gas, by using a bi-functional catalyst mixture, which was composed of a silicotungstic acid incorporated mesoporous catalyst [TRC-75(L)] and a commercial Cu–Zn based catalyst. Higher DME selectivity values were obtained by using TRC-75(L), than commercial γ-alumina at 50 bars. Presence of CO₂ in the feed stream caused significant enhancement in DME selectivity. Results showed that DME selectivity of about 0.85 was obtained in a temperature range 250–275 °C in the presence of 10 % CO₂. In fact, CO₂ was also used as a resource to produce DME at lower temperatures. Reverse dry reforming and ethanol formation reactions were observed as side reactions, especially at higher temperatures. Results also proved that direct synthesis of DME from syngas has major CO conversion and DME selectivity advantages over the two step process involving consecutive methanol synthesis and dehydration steps.     

Polymer-based tubular microbots: role of composition and preparation

The influence of the composition and electropolymerization conditions upon the propulsion of new template-prepared polymer-based bilayer microtubular microbots is described. The effects of different electropolymerized outer layers, including polypyrrole (PPy), poly(3,4-ethylenedioxythiophene) (PEDOT), polyaniline (PANI), and of various inner catalytic metal surfaces (Ag, Pt, Au, Ni-Pt alloy), upon the movement of such bilayer microtubes are evaluated and compared. Electropolymerization conditions, such as the monomer concentration and medium (e.g. surfactant, electrolyte), have a profound effect upon the morphology and locomotion of the resulting microtubes. The most efficient propulsion is observed using PEDOT/Pt microbots that offer a record-breaking speed of over 1400 body lengths s(-1) at physiological temperature, which is the fastest relative speed reported to date for all artificial micro/nanomotors. An inner Pt-Ni alloy surface is shown useful for combining magnetic control and catalytic fuel decomposition within one layer, thus greatly simplifying the preparation of magnetically-guided microbots. Polymer-based microbots with an inner gold layer offer efficient biocatalytic propulsion in low peroxide level in connection to an immobilized catalase enzyme. Metallic Au/Pt bilayer microbots can also be prepared electrochemically to offer high speed propulsion towards potential biomedical applications through functionalization of the outer gold surface. Such rational template preparation and systematic optimization of highly efficient microbots hold considerable promise for diverse practical applications.     

rhAPC reduces the endothelial cell permeability via a decrease of contractile tensions induced by endothelial cells

All cells generate contractile tension. This strain is crucial for mechanically controlling the cell shape, function and survival. In this study, the CellDrum technology quantifying cell's (the cellular) mechanical tension on a pico-scale was used to investigate the effect of lipopolysaccharide (LPS) on human aortic endothelial cell (HAoEC) tension. The LPS effect during gram-negative sepsis on endothelial cells is cell contraction causing endothelium permeability increase. The aim was to finding out whether recombinant activated protein C (rhAPC) would reverse the endothelial cell response in an in-vitro sepsis model. In this study, the established in-vitro sepsis model was confirmed by interleukin 6 (IL-6) levels at the proteomic and genomic levels by ELISA, real time-PCR and reactive oxygen species (ROS) activation by florescence staining. The thrombin cellular contraction effect on endothelial cells was used as a positive control when the CellDrum technology was applied. Additionally, the Ras homolog gene family, member A (RhoA) mRNA expression level was checked by real time-PCR to support contractile tension results. According to contractile tension results, the mechanical predominance of actin stress fibers was a reason of the increased endothelial contractile tension leading to enhanced endothelium contractility and thus permeability enhancement. The originality of this data supports firstly the basic measurement principles of the CellDrum technology and secondly that rhAPC has a beneficial effect on sepsis influenced cellular tension. The technology presented here is promising for future high-throughput cellular tension analysis that will help identify pathological contractile tension responses of cells and prove further cell in-vitro models.     

A Framework for a Meta-Semantic Language for Smart Component-Adapters

Software modeling based on the assembly of reusable components to support software development has not been successfully implemented on a wide scale. Several models for reusable software components have been suggested which primarily address the wiring-level connectivity problem. While this is considered necessary, it is not sufficient to support an automated process of component assembly. Two critical issues that remain unresolved are (1) semantic modeling of components, and (2) deployment process that supports automated assembly. The first issue can be addressed through domain-based standardization that would make it possible for independent developers to produce interoperable components based on a common set of vocabulary and understanding of the problem domain. This is important not only for providing a semantic basis for developing components but also for the interoperability between systems. The second issue is important for two reasons: (a) eliminate the need for developers to be involved in the final assembly of software components, and (b) provide a basis for the development process to be potentially driven by the user. To resolve the above remaining issues (1) and (2), a late binding mechanism between components based on meta-protocols is required. In this paper we address the above issues by proposing a generic framework for the development of software components and an interconnection language, COMPILE, for the specification of software systems from components. The computational model of the COMPILE language is based on late and dynamic binding of the components' control, data, and function properties [1] through the use of adapters. The use of asynchronous callbacks for method invocation allows control binding among components to be late and dynamic. Data exchanged between components is defined through the use of a meta-language that can describe the semantics of the information but without being bound to any specific programming language type representation. Late binding to functions is accomplished by maintaining domain-based semantics as component meta-information. This information allows clients of components to map generic requested service to specific functions.     

An Investigation in the Use of Ozone Gas in the Bleaching of Cotton Fabrics

Ozone, composed of three atoms of oxygen, can be used to oxidize many inorganic and organic impurities. Because of its high oxidizing capacity, the opportunities and parameters of ozone gas use in bleaching of cotton fabrics were researched in this study. It was found that in a very short time cotton fabrics can be bleached if the water content of cotton-woven fabric was 60% and the pH of the water impregnated was 7. Moreover, ozonation at room temperature was shown to be more efficient than ozonation at high to medium temperatures.     

Recent practices on wastewater reuse in Turkey.

Reuse of wastewater for irrigational purposes in agriculture has been a widely applied practice all around the world compared to such applications in industries. In most of the developing countries, high costs of wastewater treatment stimulate the direct reuse of raw or partly treated effluent in irrigation despite the socio-cultural objections in some countries regarding religious rituals towards consuming wastewater. In Turkey, reuse applications in agriculture have been in use by indirect application by means of withdrawing water from the downstream end of treatment plants. Such practices affected the deterioration of surface water resources due to the lack of water quality monitoring and control. However, more conscious and planned reuse activities in agriculture have recently started by the operation of urban wastewater treatment plants. Turkey does not face any severe water scarcity problems for the time being, but as the water resources show the signs of water quality deterioration it seems to be one of the priority issues in the near future. The industrial reuse activities are only at the research stage especially in industries consuming high amounts of water. In-plant control implementation is the preferred effort of minimizing water consumption in such industries. The current reuse activities are outlined in the article forming an example from a developing country.     

Construction of saliency map and hybrid set of features for efficient segmentation and classification of skin lesion

Skin cancer is being a most deadly type of cancers which have grown extensively worldwide from the last decade. For an accurate detection and classification of melanoma, several measures should be considered which include, contrast stretching, irregularity measurement, selection of most optimal features, and so forth. A poor contrast of lesion affects the segmentation accuracy and also increases classification error. To overcome this problem, an efficient model for accurate border detection and classification is presented. The proposed model improves the segmentation accuracy in its preprocessing phase, utilizing contrast enhancement of lesion area compared to the background. The enhanced 2D blue channel is selected for the construction of saliency map, at the end of which threshold function produces the binary image. In addition, particle swarm optimization (PSO) based segmentation is also utilized for accurate border detection and refinement. Few selected features including shape, texture, local, and global are also extracted which are later selected based on genetic algorithm with an advantage of identifying the fittest chromosome. Finally, optimized features are later fed into the support vector machine (SVM) for classification. Comprehensive experiments have been carried out on three datasets named as PH2, ISBI2016, and ISIC (i.e., ISIC MSK‐1, ISIC MSK‐2, and ISIC UDA). The improved accuracy of 97.9, 99.1, 98.4, and 93.8%, respectively obtained for each dataset. The SVM outperforms on the selected dataset in terms of sensitivity, precision rate, accuracy, and FNR. Furthermore, the selection method outperforms and successfully removed the redundant features.     

Exergoeconomic analysis and optimization of combined heat and power production: A review

Exergoeconomics is also called thermoeconomics, and thermoeconomic analysis methodologies combine economic and thermodynamic analysis by applying the cost concept to exergy which accounts for the quality of energy. The main concept of thermoeconomics is the exergetic cost and it deals with cost accounting methods. This paper is a review on the exergoeconomic analysis and optimization of combined heat and power production (CHPP). A brief historical overview on the exergoeconomics analysis and optimization is given. The concept of exergetic cost and cost accounting methods are discussed. An application of relevant formulation is given using a diesel engine powered cogeneration system as an example. Main thermoeconomic methodologies available in literature are described and their advantages and disadvantages with respect to one another are compared and discussed through a well-known problem, namely CGAM. Important studies on thermoeconomic analysis and optimization of combined heat and power production are listed based on the methodology used and the type of system considered.