Effect of impression valve system on adhesion force of impression materials to edentulous maxillary jaw: a preliminary clinical study

Objective: The purpose of this preliminary clinical study was to evaluate the effect of novel impression valve system (IVS) on adhesion force of different impression materials to edentulous maxilla. Background data: Impression materials and techniques have an important role in complete denture success. During the functional impression with an individual impression tray (IIT), high adhesive forces exist between edentulous ridge and impression material. Removing the IIT from the mouth with minimal force provides the most accurate and non-deformed impression. Materials and methods: This study included twenty maxillary edentulous patients (n?=?20). Patients who had palatal torus, anatomic undercut, gagging reflex, and flabby ridges were excluded from the study. The age range of the participants was 55–70. All patients gave written informed consent. Two impression materials – zinc oxide eugenol (ZOE) and alginate – were used as experimental material. The digital dynamometer was used to determine the adhesion force of impression materials with and without IVS to edentulous maxilla. The mean values of the adhesion forces were analyzed using the Wilcoxon signed-ranks test (α = 0.05). Results: The effect of IVS on adhesion force was found to be statistically significant (p < 0.05). There were also statistical differences between the ZOE and alginate groups (p < 0.05). Conclusions: The IVS is useful to remove the functional impression from the mouth without any deformation and detaching in cases which high adhesive force occurs.     

Determination of the biodegradation of phenolated wood-based molding materials by strength loss method

The biodegradability of new molding materials from HCl-catalyzed phenolated wood was investigated by using some dynamic and static mechanical strength loss methods.     

Determination of mechanical and hydraulic properties of polyacrylamide-added bentonite-sand mixtures

Bulletin of Engineering Geology and the Environment - Bentonite-sand mixtures are typically used in engineering applications such as cutoff walls for waste containment facilities or barriers in...     

Framework for Operation and Maintenance (OAM) in Optical Burst Switched Networks

The problem of operation and maintenance (OAM) in optical burst switched (OBS) networks is not addressed by the optical-networking community even though OBS has been gaining research interest in recent years. In this paper, we introduce a functional model of OBS networks and an OAM architecture that is designed to meet the operational requirements based on this model. We present the first framework to realize OAM in OBS networks, including OAM activities, OAM-aware OBS nodes, OAM information and communication models and protocols. A number of practical examples of possible network failures and the corresponding reactions are presented.     

Steady aerodynamic characteristics of a wing flying over a nonplanar ground surface Part II: Channel

The steady aerodynamic characteristics of a wing flying over a channel are investigated using a boundary-element method. The present method is validated by comparing the computed results with the measured data. Compared with a flat ground surface, the channel fence augmented the lift increase and induced drag reduction. When the fence is lower than the wing height, the gap between the wingtip and the fence does not affect the aerodynamic characteristics of the wing much. When the fence is higher than the wing height, the close gap increased the lift. The induced drag is reduced when the wing is placed near the ground or at the same height as the fence. It is believed that present results can be used in the conceptual design of the high-speed ground transporters flying over the channel.     

Measurement of glucose,sucrose and lactose in food samples with enzyme-immobilised packed-bed column reactors integrated to an amperometric enzyme electrode

An amperometric enzyme electrode integrated with packed-bed column reactors containing immobilised enzymes was improved to measure glucose, sucrose and lactose content of food samples with only one sampling. Performance parameters of the system were investigated on the bases of linearity, sensitivity and response time. Those values were found to be 20 mM, 24.9 nA/mM and 20 s for glucose; 20 mM, 12.0 nA/mM and 3 min for sucrose; 12 mM, 10.8 nA/mM and 4 min for lactose, respectively. Overall analysis time for three analytes with one sampling was less than 8 min without pretreatment and interference of electroactive compounds and substrates. Glucose, sucrose and lactose content of the model and food samples were measured with both the improved system and commercial enzyme kits. There was high correlation between the results. This gives us the opportunity to use the improved electrode system for determination of glucose, sucrose and lactose in food samples. Also this result was found to be very promising in extending the spectrum of detectable analytes simply by addition of new columns containing immobilised enzymes that are specific to target analytes.     

Coenzyme Q10 supplementation and diastolic heart functions in hemodialysis patients: A randomized double‐blind placebo‐controlled trial

Coenzyme Q10 (CoQ10) supplementation has been shown to improve diastolic heart function in various patient cohorts. Systolic and diastolic dysfunctions are common in patients with end‐stage renal disease. Favorable effects of CoQ10 on cardiac functions are yet to be seen in hemodialysis patients. We aimed to evaluate effect of CoQ10 supplementation on diastolic function in a cohort of maintenance hemodialysis patients. This was a prospective, double‐blind, placebo‐controlled, crossover study in which all patients received placebo and oral CoQ10 200 mg/d during the 8 weeks in each phase, with a 4‐week washout period. Participants underwent conventional and tissue Doppler echocardiography before and after each study phase. Parameters characterizing left ventricle diastolic function and other standard echocardiographic measurements were recorded. Twenty‐eight patients were randomized, but 22 patients completed study protocol. Intraventricular septum (IVS) thickness and left ventricle mass were significantly decreased in CoQ10 group (P = 0.03 and P = 0.01, respectively). Myocardial peak systolic and early diastolic velocities derived from IVS were significantly increased (P = 0.048 and P = 0.04, respectively). Isovolumetric relaxation time and E/Em ratio calculated for IVS also significantly reduced in CoQ10 group (p = 0.02 and p = 0.04, respectively). There was no significant difference in any of the studied echocardiographic parameters in placebo group. The results of this study showed that CoQ10 supplementation did not significantly improved diastolic heart functions compared with placebo in maintenance hemodialysis patients.     

Geological Setting and the Validity of the Petroleum System Logic in the Taurus Belt of Turkey

The Taurus Belt region is located in the southern part of Turkey and includes the Tauridia highlands, the Autochthonous Taurus Units and the Allochthonous Units in the southern and northern flank of the Tauridia, respectively, and the Gondwanian Units in the southern part of the entire area. The total thickness of Palaeozoic to Cenozoic sediments ranges from 2,500 m (for the Allochthonous Units) to 10,700 m (for the Autochthonous Taurus Units). All Taurus units display many characteristics of a carbonate platform. Previous studies in the Taurus region indicate that the Paleozoic successions in the eastern and central parts of that region include some intervals of potential petroleum source rocks. Some hydrocarbon indications were found in the Akseki, Guzelsu, and Ucyildiz areas.