Motion of nanodroplets near chemical heterogeneities

We investigate the dynamics of nanoscale droplets in the vicinity of chemical steps which separate parts of a substrate with different wettabilities. Due to long-ranged dispersion forces, nanodroplets positioned on one side of the step perceive the different character of the other side even at some distances from the step, leading to a dynamic response. The direction of the ensuing motion of such droplets does not only depend on the difference between the equilibrium contact angles on these two parts but in particular on the difference between the corresponding Hamaker constants. Therefore the motion is not necessarily directed towards the more wettable side and can also be different from that of droplets which span the step.Comment: 6 pages, 6 figure

Prevalence of depression among infertile couples in Iran: A meta-analysis study

Background: Several studies have been conducted in Iran in order to investigate the prevalence of depression among infertile couples. However, there is a remarkable diversity among the results. This meta-analysis was conducted to estimate an overall prevalence rate of depression among infertile couples in Iran. Methods: International and national electronic databases were searched up to June 2011 including MEDLINE, Science Citation Index Expanded, Scopus, SID, MagIran, and IranMedex as well as conference databases. Furthermore, reference lists of articles were screened and the studies' authors were contacted for additional references. Cross-sectional studies addressing the prevalence of depression among infertile couples were included in this meta-analysis. We assessed 12 separate studies involving overall 2818 participants of which 1251 had depression. Results: Overall prevalence rate of depression among infertile couples was 0.47 (95% CI: 0.40, 0.55). The prevalence rate of depression was 0.44 (95% CI: 0.32, 0.56) during 2000 to 2005 and 0.50 (95% CI: 0.43, 0.57 during 2006 to 2011. The prevalence rate of depression was 0.46 (95% CI: 0.39, 0.53) among women and 0.47 (95% CI: 0.40, 0.54) among men. Conclusion: Not only the prevalence of depression in infertile couples was high but also had increasing growth in recent years. Furthermore, despite many studies conducted addressing the prevalence of depression in infertile couples, there is however a remarkable diversity between the results. Thus, one can hardly give a precise estimation of the prevalence rate of depression among infertile couples in Iran now

Motion of nanodroplets near edges and wedges

Nanodroplets residing near wedges or edges of solid substrates exhibit a disjoining pressure induced dynamics. Our nanoscale hydrodynamic calculations reveal that non-volatile droplets are attracted or repelled from edges or wedges depending on details of the corresponding laterally varying disjoining pressure generated, e.g., by a possible surface coating.Comment: 12 pages, 7 figure

Textural and chemical attributes of sausages developed from talang queenfish (Scomberoides commersonnianuus) mince and surimi

Talang Queenfish (Scomberoides commersonnianuus) is relatively inexpensive fish with low consumption in Fars Province, South of Iran. In this research which was performed in 2011, sausages were produced from mince and surimi of this species and some physicochemical attributes of the products were investigated during 60 days of cold storage at 4 °C. According to the results, free fatty acid (FFA), peroxide and TBARS values of minced fish sausage were significantly higher than those for surimi sausage (p<.05). It was found that minced fish sausage significantly had (P<.05) more breaking and gel strength compared to the surimi sausage at each time of preservation. There were significant differences (P<.05) in L*, a* and whiteness colorimetric parameters of the sausages. Scanning electron microscopy images demonstrated that the surface porosity increased during preservation. This study demonstrated that surimi sausage had better textural and chemical characteristics than minced fish sausage during cold storage

Modelling the evaporation of nanoparticle suspensions from heterogeneous surfaces

We present a Monte Carlo (MC) grid-based model for the drying of drops of a nanoparticle suspension upon a heterogeneous surface. The model consists of a generalised lattice-gas in which the interaction parameters in the Hamiltonian can be varied to model different properties of the materials involved. We show how to choose correctly the interactions, to minimise the effects of the underlying grid so that hemispherical droplets form. We also include the effects of surface roughness to examine the effects of contact-line pinning on the dynamics. When there is a `lid' above the system, which prevents evaporation, equilibrium drops form on the surface, which we use to determine the contact angle and how it varies as the parameters of the model are changed. This enables us to relate the interaction parameters to the materials used in applications. The model has also been applied to drying on heterogeneous surfaces, in particular to the case where the suspension is deposited on a surface consisting of a pair of hydrophilic conducting metal surfaces that are either side of a band of hydrophobic insulating polymer. This situation occurs when using inkjet printing to manufacture electrical connections between the metallic parts of the surface. The process is not always without problems, since the liquid can dewet from the hydrophobic part of the surface, breaking the bridge before the drying process is complete. The MC model reproduces the observed dewetting, allowing the parameters to be varied so that the conditions for the best connection can be established. We show that if the hydrophobic portion of the surface is located at a step below the height of the neighbouring metal, the chance of dewetting of the liquid during the drying process is significantly reduced.Comment: 14 pages, 14 figure

On the feasibility of attribute-based encryption on Internet of Things devices

Attribute-based encryption (ABE) could be an effective cryptographic tool for the secure management of Internet of Things (IoT) devices, but its feasibility in the IoT has been under-investigated thus far. This article explores such feasibility for well-known IoT platforms, namely, Intel Galileo Gen 2, Intel Edison, Raspberry pi 1 model B, and Raspberry pi zero, and concludes that adopting ABE in the IoT is indeed feasible

Iranian version of speech, spatial, and qualities of hearing scale: A psychometric study

Evaluation of communication abilities in the elderly is crucial for activities which will be performed to improve their quality of life. A valid and reliable questionnaire is needed for assessing communication abilities. We aimed to translate and validate the speech, spatial, and qualities of hearing scale (SSQ) in Iran. The forward-backward procedure was applied to translate the questionnaire from English into Persian. After linguistic validation and pilot study, a cross-sectional study was carried out, and psychometric properties of the Iranian version of the SSQ were tested. Number of 333 elderly individuals with impaired hearing completed the questionnaire. Number 48.3 were hearing aid users and 51.7 was not. Reliability was assessed by internal consistency (Cronbach's alpha) and test-retest analysis. Exploratory factor analysis was performed for extracting factor structure of the Persian version of SSQ. Confirmatory factor analysis was performed to compare different models of factor loadings. The Mean age of participants was 62.00 years (SD=9.58 years), and the mean SSQ score was 5.1 (SD=1.2, ranged: 3.17-6.27). Reliability evaluation revealed high internal consistency and good test- retest reliability. Cronbach's alpha coefficient was 0.96 and the Pierson Correlation at test-retest analysis was 0.73 for Quality of hearing factor, 0.88 for Spatial and o.73 for Speech understanding factor. The results of exploratory factor analysis (EFA) indicated a four-factor solution for P-SSQ that jointly accounted for 52.40 of the variance observed. Confirmatory factor analysis approved the three factor solution but proposed a possible fourth factor. The Iranian version of the SSQ has acceptable psychometric properties, and it will be helpful for assessing different kinds of communication abilities in the Iranian elderly population. © 2016 Tehran University of Medical Sciences. All rights reserved