Nanoleakage within adhesive-dentin interfaces made with simplified ethanol-wet bonding

Objective: The aim of the present study was to evaluate the effects of the simplified ethanol-wet bonding technique and conventional water-wet bonding technique on short term nanoleakage within hybrid layers made with two different etch-and-rinse adhesives (Single Bond 2 and Prime & Bond NT). Materials and methods: Flat dentin surfaces from bovine incisors were prepared and finished with wet 600-grit abrasive papers, then divided into groups to be bonded with one of the adhesives. After etching and rinsing, dentin surfaces were either moistened with water (water-wet bonding technique) or moistened with absolute ethanol for 1 min (ethanol-wet bonding technique). Then, adhesives were applied, and composite buildups were done. Bonded teeth samples were sectioned into resin–dentin samples by means of a low speed diamond saw under water cooling. Specimens were immersed into a 50% (w/v) solution of silver ammoniacal nitrate for 18 h and exposed to photodeveloping solution for 6 h. The amount of silver nitrate uptake within the adhesive layer, or hybrid layer, was measured with energy dispersive spectroscopy (EDS) in different regions (n = 30). Results: Simplified ethanol-wet bonding significantly reduced nanoleakage within resin–dentin interfaces made with Single Bond 2 and Prime & Bond NT, but improvement at the nanoleakage of Single Bond 2 was only significant. Conclusion: Simplified ethanol-wet bonding may improve quality of hybrid layers made with commercially available simplified etch-and-rinse adhesives. But benefits of ethanol-wet bonding may depend on product.     

Prophylactic vasopressin during laparoscopic salpingotomy for ectopic pregnancy

Monoamine oxidase (MAO) released from the rat liver into plasma and the activity levels of lipid peroxide (LPO) and superoxide dismutase (SOD) in liver tissue were investigated after pretreatment of rats with the perilobular hepatotoxin allyl formate (AF). When 3H-pargyline was given to AF-pretreated rats, the levels of 3H-pargyline labelled MAO in rat plasma were increased to 38% (p < 0.01 vs control), but the radioactivity was decreased to 35% (p < 0.05 vs control). The molecular weight of MAO subunits in plasma was similar to that of MAO subunits in liver (about 60,000) as determined by SDS electrophoresis. Liver tissue LPO levels in these rats were increased, whereas SOD activity was decreased. These results suggest that MAO in liver mitochondria was released into plasma as a consequence of membrane disorder.     

Removal of limonin bitterness by treatment of ion exchange and adsorbent resins

This study, the selective removal of limonin bitterness from Washington navel orange juice by batch adsorption to the Amberlite XAD-16HP and Dowex Optipore L285 was investigated and the determination of some compositional changes that occurred with orange juices debittering using adsorption resins were the primary focus. Amberlite XAD-16HP and Dowex Optipore L285 have been successfully used to reduce bitterness to acceptable levels in Washington navel orange juices. Amberlite XAD-16HP does not have any important negative effects on the quality characteristics of orange juices. However, Dowex Optipore L285 reduces the titratable acidity (TA) in the orange juices and so increases the content of soluble solids contents (SSC), pH value, and ratio accordingly.     

Comparison of the impact of some Minkowski metrics on VQ/GMM based speaker recognition

This paper evaluates the impact of three special forms of the Minkowski metric (Euclidean, City Block, and Chebychev distances) on the performance of the conventional vector quantization (VQ) and Gaussian mixture model (GMM) based closed-set text-independent speaker recognition systems, in terms of recognition rate and confidence on decisions. For the VQ based system, evaluations are carried out using the two most common clustering algorithms, LBG and K-means, and it is revealed which clustering algorithm and distance pair should be used to exploit the best attribute of both to achieve the best recognition rate for a given codebook size. In the case of GMM based system, we introduce the metrics into the GMM using a concatenation of the LBG and K-means algorithms in estimating the initial mean vectors, to which the system performance is sensitive, and explore their impact on system performance. We also make comparison of results obtained from evaluations on clean speech (TIMIT) and telephone speech databases (NTIMIT and NIST2001) with the modern classifiers VQ-UBM and GMM-UBM. It is found that there are cases where conventional VQ based system outperforms the modern systems. Moreover, the impact of distance metrics on the performance of the conventional and modern systems depends on the recognition task imposed (verification/identification).     

Simulation-based analysis of flow due to traveling-plane-wave deformations on elastic thin-film actuators in micropumps

One of the propulsion mechanisms of microorganisms is based on propagation of bending deformations on an elastic tail. In principle, an elastic thin-film can be placed in a channel and actuated for pumping of the fluid by means of introducing a series of traveling-wave deformations on the film. Here, we present a simulation-based analysis of transient, two-dimensional Stokes flow induced by propagation of sinusoidal deformations on an elastic thin-film submerged in a fluid between parallel plates. Simulations are based on a numerical model that solves time-dependent Stokes equations on deforming finite-element mesh, which is due to the motion of the thin-film boundary and obtained by means of the arbitrary Lagrangian Eulerian method. Effects of the wavelength, frequency, amplitude and channel’s height on the time-averaged flow rate and the rate-of-work done on the fluid by the thin-film are demonstrated and grouped together as the flow-rate and power parameters to manifest a combined parametric dependence.     

Smartphone addiction and its relationship with social anxiety and loneliness

Individuals with psychosocial problems such as social phobia or feelings of loneliness might be vulnerable to excessive use of cyber-technological devices, such as smartphones. We aimed to determine the relationship of smartphone addiction with social phobia and loneliness in a sample of university students in Istanbul, Turkey. Three hundred and sixty-seven students who owned smartphones were given the Smartphone Addiction Scale (SAS), UCLA Loneliness Scale (UCLA-LS), and Brief Social Phobia Scale (BSPS). A significant difference was found in the mean SAS scores (p?<?.001) between users who declared that their main purpose for smartphone use was to access social networking sites. The BSPS scores showed positive correlations with all six subscales and with the total SAS scores. The total UCLA-LS scores were positively correlated with daily life disturbance, positive anticipation, cyber-oriented relationship, and total scores on the SAS. In regression analyses, total BSPS scores were significant predictors for SAS total scores (β?=?0.313, t?=?5.992, p?<?.001). In addition, BSPS scores were significant predictors for all six SAS subscales, whereas UCLA-LS scores were significant predictors for only cyber-oriented relationship subscale scores on the SAS (β?=?0.130, t?=?2.416, p?<?.05). The results of this study indicate that social phobia was associated with the risk for smartphone addiction in young people. Younger individuals who primarily use their smartphones to access social networking sites also have an excessive pattern of smartphone use.     

An expert system approach for die and mold making operations

In the modern manufacturing of sophisticated parts with 3D sculptured surfaces, die and mold making operations are the most widely used machining processes to remove unwanted material. To manufacture a die or a mold, many different cutting tools are involved, from deep hole drills to the smallest ball nose end mills. Since the specification of each tool is very different from each other, each mold or die is specific with their complicated shapes and many machining rules exist to consider, a great deal of expertise is needed in planning the machining operations. An expert system (DieEX) developed for this purpose is described in the present work. The geometry and the material of the workpiece, tool material, tool condition and operation type are considered as input values and various recommendations about the tool type, tool specifications, work holding method, type of milling operation, direction of feed and offset values are provided.     

On nonlocal microfluid mechanics

The simple microfluid theory of Eringen [1] is generalized to include nonlocal effects. The balance laws, jump conditions, and constitutive equations are obtained. The nonlocal intermolecular forces, energy and entropy are accounted for by nonlocal field residuals and functional constitutive equations of space type. The second law of thermodynamics is used to obtain specific forms of these residuals, constitutive equations and restrictions to be imposed. The linear theory is developed fully for the micromorphic and micropolar nonlocal fluids. The nonlocal effects are shown to include surface tension and surface stresses. Passage is made to material gradient theories.     

A continuum theory of rigid suspensions

A continuum theory of rigid suspension is presented. The theory modifies and extends the Batchelor^1,2 theory of fiber suspensions to heat conducting thermo-viscous Newtonian solvents carrying rigid suspensions.