Repulsion-based model for contact angle saturation in electrowetting

We introduce a new model for contact angle saturation phenomenon in electrowetting on dielectric systems. This new model attributes contact angle saturation to repulsion between trapped charges on the cap and base surfaces of the droplet in the vicinity of the three-phase contact line, which prevents these surfaces from converging during contact angle reduction. This repulsion-based saturation is similar to repulsion between charges accumulated on the surfaces of conducting droplets which causes the well known Coulombic fission and Taylor cone formation phenomena. In our model, both the droplet and dielectric coating were treated as lossy dielectric media (i.e., having finite electrical conductivities and permittivities) contrary to the more common assumption of a perfectly conducting droplet and perfectly insulating dielectric. We used theoretical analysis and numerical simulations to find actual charge distribution on droplet surface, calculate repulsion energy, and minimize energy of the total system as a function of droplet contact angle. Resulting saturation curves were in good agreement with previously reported experimental results. We used this proposed model to predict effect of changing liquid properties, such as electrical conductivity, and system parameters, such as thickness of the dielectric layer, on the saturation angle, which also matched experimental results.     

Effect of perceived ease of use on librarians' e-skills: Basis for library technology acceptance intention

Despite the widespread application of technology in the 21st century, making informed decisions regarding its acceptance in organisations is a function of several factors, particularly in developing countries, due to factors such as rising cost of the information technology infrastructure and low technological exposure. A model that incorporated perceived ease of use (PEOU) and e-Skills to examine librarians' intention for actual library technology acceptance was tested. The correlational research design, along with a multistage sampling procedure, was applied to select samples to reduce the sample to a manageable proportion. Professional librarians and library officers in four university libraries provided the data for the study. Results showed that e-Skill is the model's strongest determinant of technology acceptance intention among librarians. Also, PEOU will significantly moderate librarians' intention towards library technology acceptance when e-Skills are insufficient. From these outcomes, the understanding of the determinants of behavioural intention captured in the Technology Acceptance Model (TAM) and the Unified Theory of Acceptance and Use of Technology (UTAT) is extended and refined.     

Palestinian media landscape: Experiences,narratives, and agendas of journalists under restrictions

This study aims to increase our understanding of the dynamics of the Palestinian media and the conditions and circumstances in which they work, including both the conflict with Israel and the internal political strife within Palestinian society. It is based on the use of qualitative research methods and was conducted in two stages. First, we performed a mapping of Palestinian media outlets. Data on these Palestinian media outlets were collected online from the West Bank-based Palestinian Authority’s Ministry of Information website, the Gaza-based Hamas government’s Ministry of Information website, and statements published by Palestinian media outlets on their websites describing their affiliation and ownership. Second, to gain a more in-depth understanding of the dynamics and experience of practicing journalism in a situation of asymmetrical conflict, semistructured in-depth interviews were conducted with 25 professional local Palestinian journalists working for local media outlets in the Gaza Strip, the West Bank, and East Jerusalem. Through this study we aim to learn more about how groups shape and express their narratives and agendas through the media when restricted by the conditions, pressures, and limitations of asymmetrical conflict.     

A corpus-based discourse analysis of the vision and mission statements of universities in Turkey

This article presents findings from a corpus-assisted discourse analysis of mission and vision statements of 105 state and 66 private/foundation universities in Turkey. The paper combines a corpus-based approach with critical discourse analysis to interpret the data in relation to its institutional as well as socio-political context. It argues that the mission and vision statements are marked by a need for reassuring their legitimacy and the demands of a growing tertiary market. The historical and cultural backgrounds of the development of universities in Turkey, as well as political and economic conditions, are also decisive in the shaping of mission and vision statement of universities.     

Legendre wavelet operational matrix of derivative for optimal control in a convective–diffusive fluid problem

We consider the problem of controlling the model of one-dimensional fluid flow through a soil packed tube in which a contaminant is initially distributed. A fluid is pumped through a tube to remove the contaminant. The control problem is to determine the optimal convective velocity due to the fluid being pumped by minimizing a given performance criterion. The performance criterion is chosen to be a combination of the total contaminant at the final time and the cost of the control. The set of orthogonal Fourier trigonometry series is used as a basis function of the Galerkin procedure to lump the distributed parameter system. A Legendre wavelet operational matrix of derivative is used to approximate the control and modal state variables. The main characteristics of this technique is that it reduces these problems to those of solving a system of algebraic equations, thus greatly simplifying the problem. The effectiveness of the proposed approach is illustrated numerically and the results are quite satisfactory.     

Observer design for constrained nonlinear systems with application to secure communication

In this paper, a constrained regularized least square (RLS) state estimator is developed for deterministic discrete-time nonlinear dynamical systems subject to a set of equality and/or inequality constraints. The stability of the estimation error is rigorously analyzed. The proposed estimator is then used to handle the important problem of secure communication. At the transmitting end, the output of the constrained unified chaotic system is used as a chaotic mask to achieve a satisfactory and typical secure communication scheme. The encrypted data signal is injected into the transmitter and simultaneously transmitted to the receiver through a public channel. At the receiving end, the constrained RLS estimator is used to reconstruct the states of the constrained unified chaotic system. Simulation results are presented to show the impact of the imposed constraints on the waveform and the pattern of the generated chaotic signal as well as the ability of the proposed estimator to synchronize the actual and estimated states of the constrained unified chaotic system. Moreover, the proposed estimator is applied to recover discrete signals such as digital images where computer simulation results are provided to show the effectiveness of the proposed estimation scheme.     

Biological variations of ADAMTS13 and von Willebrand factor in human adults

Background:

The ultra-large von Willebrand factor (vWF) multimers are very active and must be degraded by ADAMTS13 for optimal activity. A severe functional deficiency of ADAMTS13 has been associated with thrombotic thrombocytopenic purpura. The correct interpretation of patient vWF and ADAMTS13 plasma levels requires an understanding of the biological variation associated with these analytes. In the present paper, we aimed to determine the biological variation of ADAMTS13 and vWF in human adults.

Materials and methods:

Blood samples were collected weekly from 19 healthy subjects for 5 consecutive weeks. vWF activity and antigenicity were determined using aggregometric and immunoturbidimetric methods. ADAMTS13 antigenicity and activity were determined by ELISA.

Results:

The within-subject biological variations for vWF activity and antigenicity were 8.06% and 14.37%, respectively, while the between-subject biological variations were 18.5% and 22.59%, respectively. The index of individuality for vWF activity was 0.44, while vWF antigenicity was 0.64. Similarly, ADAMTS13 activity and antigenicity within-subject biological variations were 12.73% and 9.75%, respectively, while between-subject biological variations were 9.63% and 6.28%, respectively. The ADAMTS13 indexes of individuality were 1.32 and 1.55, respectively.

Conclusion:

We report high biological variation and individuality in vWF antigenicity and activity levels. However, ADAMTS13 antigenicity and activity displayed high biological variation, but low individuality. Thus, population-based reference intervals may be useful for monitoring ADAMTS13 antigenicity and activity, but not for vWF, which displays high individuality. These findings should be considered when determining the reference interval and other clinical variables associated with ADAMTS13 and vWF levels.     

Perception of spiritual health: A qualitative content analysis in Iranian older adults

The present study was performed with the aim to explain older people’s perceptions of spiritual health. It was conducted using the conventional content analysis method. Twelve individuals aged 60 years or older with normal cognition participated in the study using purposive sampling. Data were collected by in-depth interviews. Data analysis performed using standard method of thematic analysis.The average age of the study participants was 71.25 ± 9.48. The data analysis resulted in three main categories of spiritual insight, spiritual function, and spiritual affection. The spiritual insight included cognition of God and belief in Him, understanding of the divine religions and belief in them, self-cognition, cognition of the creation, and belief in the hereafter. This category included the two subcategories of spiritual cognition and spiritual belief. Spiritual function represented the interactions that the older people experienced in relations with God, themselves, and others. This category consisted of the subcategories of relationship with God, relationship with others, and self-cultivation. The spiritual affection included loving God and other humans and consisted of the three subcategories of spiritual affections to God, others, and oneself. This study presents in-depth data on the concept of spiritual health from older people’s viewpoints. These findings would help healthcare teams in designing appropriate interventions for older people’s health promotion. Also, by using the results of this research, health researchers design more appropriate tools for measuring spiritual health based on older people’s perception of the concept of spiritual health.     

Shaping global teacher identity in a short-term mobility programme

This article explores the shaping of Australian and Malaysian pre-service teachers’ possible selves in a short-term mobility programme. With the theory of possible selves, individuals imagine who they will become based on their past and current selves. The focus of the research was on pre-service teachers’ possible selves as global and culturally responsive teachers. The experiential learning through participation in the programme allowed participants to consider their future possible selves as teachers with a deeper understanding of diverse learners’ needs and how they might strive to address these needs in their own classrooms. The scaffolding of reflections in the programme encouraged the pre-service teachers to take on multiple perspectives, to step outside their comfort zones and in many ways to see the world from different eyes. The research found that through experiential learning in the short-term mobility programme both the Australian and Malaysian pre-service teachers gained in positioning their cultural selves currently and as future teachers, suggesting that there is merit in utilising the theory of possible selves in future research in the area of shaping teacher identity.