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In this paper, the wave propagation analysis of fluid-conveying Magneto-Electro-Elastic (MEE) nanotube subjected to multi-physical fields is investigated via nonlocal strain gradient elasticity theory (NSGT). To take into account the small-scale effects, the nonlocal elasticity theory of Eringen is employed. Nonlocal governing equations of MEE nanotube have been derived utilizing Hamilton’s principle. The results of this study have been verified by checking them of antecedent investigations. An analytical solution of governing equations is used to acquire wave frequencies and phase velocities. The Knudsen number is considered to study the slip boundary wall of nanotube and flow. The effects of various parameters such as multi-physical fields, the Knudsen number, different mode, length parameter, nonlocal parameter, fluid velocity, fluid effect and the slip boundary condition on wave propagation characteristics of fluid-conveying MEE nanotube are investigated in detail.

Stroke disproportionately affects people in low-income and middle-income countries. Although improvements in stroke care and outcomes have been reported in high-income countries, little is known about practice and outcomes in low and middle-income countries. We aimed to compare patterns of care available and their association with patient outcomes across countries at different economic levels.

The relation between dietary nutrients and cardiovascular disease risk markers in many regions worldwide is unknown. In this study, we investigated the effect of dietary nutrients on blood lipids and blood pressure, two of the most important risk factors for cardiovascular disease, in low-income, middle-income, and high-income countries.

A thiocyanate ion selective electrode was prepared. The electrode showed a good selectivity and sensitivity, wide dynamic range, low detection limit, fast response time and applicable for analytical samples.

Objective:To assess nurses’ knowledge about pressure ulcers in an Iranian orthopaedic ward.Method:A cross-sectional, self-report questionnaire study using Pieper´s Pressure Ulcer Knowledge Test (PUKT). Orthopaedic nurses’ knowledge about pressure ulcers was examined in two teaching hospitals in Iran. The questionnaire consisted of 41 true or false assertions, categorised according to pressure ulcer classification and onset, wound characteristics and preventive measure.Results:Of 68 nurses, 57 participated in this study (response rate of 84%); of the respondents, 68% (n=39) were women and 32% (n=18) were men. Mean age of participants was 30.2 ± 5.1 years and mean years of experience was 6.9 ± 4.6 years. The overall rate of correct responses by nurses was 70.1%. Nurses had the highest level of knowledge in the pressure ulcer prevention category and the lowest in the pressure ulcer categorisation and onset section. No relationship was found between level of knowledge and nurses’ years of experience.Conclusion:Pressure ulcer prevention is one of the most important roles of nurses in an orthopaedic setting. The results of this study suggest that orthopaedic nurses in Iran were not sufficiently knowledgeable about pressure ulcers. Therefore, there is a need to improve their knowledge with some targeted, educational programmes.Declaration of interest:There were no external sources of funding for this study. The authors have no conflicts of interest to declare.

Abstract[61Cu]-9,10-Phenanthrenequinone thiosemicarbazone ( 61Cu-PQTS), a radiolabeled anticancer compound was prepared for malignant tissue imaging studies. Copper-61 was produced viathe natZn(p, x) 61Cu nuclear reaction in a 30 MeV cyclotron (150 μA irradiation for 76 min, radionuclidic purity >95%). 61Cu-PQTS was prepared from in-house synthesized PQTS. Quality control was performed using ITLC. The biodistribution of the tracer was compared to the biodistribution of cationic copper-61 in healthy controls. 61Cu-PQTS was then administered to fibrosarcoma-bearing mice for biodistribution and co-incidence imaging studies. 61Cu-PQTS demonstrated significant tumor uptake of 2.1% ID/g and the tumor was clearly visualized in a fibrosarcoma model.

AbstractBuserelin was successively labeled with [111In]-Indium chloride after residuation with DTPA-dianhydride. Radio-chromatography showed an overall radiochemical purity of >90% (RTLC) and >95% (HPLC) at optimized conditions after labeling (specific activity: 400−450 GBq/M). The serum stability of the tracer was determined up to 24 h. The biodistribution of the tracer was determined in normal rats showing significant breast and ovaries uptakes 60 min post injection. MCF-7 cell binding of the tracer was >98%. A significant testes uptake was demonstrated in normal male rats using SPECT studies.

In this article, we propose a numerical scheme to solve the one‐dimensional undamped Sine‐Gordon equation using collocation points and approximating the solution using Thin Plate Splines (TPS) radial basis function (RBF). The scheme works in a similar fashion as finite difference methods. The results of numerical experiments are presented and are compared with analytical solutions to confirm the good accuracy of the presented scheme.© 2007 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2008

Thallium-201 (T1/2=3.04 d) in Tl+form was converted to Tl3+cation in presence of O3in 6 M HCl controlled by RTLC/gel electrophoresis methods and used in the labeling of human polyclonal antibody (HIgG) after conjugation with freshly prepared cyclic DTPA-dianhydride. The best results of the conjugation were obtained by the addition of 1 mL of a HIgG pharmaceutical solution (5 mg/ml, in phosphate buffer, pH=7) to a glass tube pre-coated with DTPA-dianhydride (0.01 mg) at 25 °C with continuous mild stirring for 30 min. The final isotonic [201Tl](III)-DTPA-HIgG complex was checked by radio-TLC using several solvent systems to ensure the formation of only one species followed by filtration through a 0.22 μ filter (specific activity= 33.7 TBq/mM, radiochemical purity >95%). Preliminary bio-distribution studies in normal and inflammation-bearing rats were performed. The target/skin and target/blood ratios were 4 and 6 after 28 h respectively, showing the selectivity of the radiopharmaceutical for the inflammatory lesions.

Compactly supported linear semiorthogonal B-spline wavelets together with their dual wavelets are developed to approximate the solutions of nonlinear Fredholm-Hammerstein integral equations. Properties of these wavelets are first presented; these properties are then utilized to reduce the computation of integral equations to some algebraic equations. The method is computationally attractive, and applications are demonstrated through an illustrative example.

We present a polynomial wavelet-type system on Sdsuch that any continuous function can be expanded with respect to these “wavelets.” The order of the growth of the degrees of the polynomials is optimal. The coefficients in the expansion are the inner products of the function and the corresponding element of a “dual wavelet system.” The “dual wavelets system” is also a polynomial system with the same growth of degrees of polynomials. The system is redundant. A construction of a polynomial basis is also presented. In contrast to our wavelet-type system, this basis is not suitable for implementation, because, first, there are no explicit formulas for the coefficient functionals and, second, the growth of the degrees of polynomials is too rapid.

This paper presents a numerical study of the flow field in a novel ‘soft’ acting peristaltic pump. The pump has potential applications wherever pumping of biological or sensitive fluids with reduced damage is required. The application of the device presented is as a blood pump. The model of the pump comprises a cylindrical tube that forms three chambers. The walls of these chambers move radially as a function of time. The pumping action is initiated by applying phased movement between the chambers. The flow is treated as laminar, unsteady, incompressible, Newtonian, and with a moving boundary. The governing equations are solved using a finite element method (FEM). An operating speed of 60 cycle min−1has been chosen. The results show that a periodic solution can be achieved after four cycles. The velocity field, streamline and shear stress are presented and discussed. The flow has generally a two‐way pulsatile nature, moving forwards and backwards. However, at the outlet, there is a net outflow over one cycle against a zero pressure head. Net flow linearly decreases to zero with increasing pressure head. Copyright © 2000 John Wiley & Sons, Ltd.

The effects of operational parameters on the results of conditional sampling studies of turbulent boundary layers have been studied for several conditional sampling techniques. It is shown that the results, such as event detection rate and phase-averaged event patterns, depend strongly on the choice of the values of these parameters. Other factors such as the existence of phase jitter in the event detections and sampling frequency of data acquisition are also found to affect the results. It is suggested that proper choice should make the event detection rate assuming either a constant or a maximum. Phase alignment is also shown to lead to improved conditional sampling results and is therefore recommended. The results suggest that discrepancies in previous conditional sampling studies could be at least partly due to the use of different operational parameters rather than due to different flow mechanisms and therefore proper care must be taken in the interpretation of the results and in comparison between the results of previous conditional sampling studies.

Two different explicit finite difference schemes for the numerical solution of the diffusion equation on a rectangular region, subject to local or nonlocal boundary conditions, the latter involving a double integral to simulate specification of mass in a curved region, are compared. These schemes, the two-dimensional 9-point Forward Time Centered Space (FTCS) explicit formula [Noye & Hayman, J Comp Math 42, 1992, 223–236] and the locally one-dimensional (LOD) method based on the classical one-dimensional FTCS formula [Noye & Hayman, J Comp Math 51, 1994, 215–228], are economical to use, are generally second-order, have bounded ranges of stability, and can be shown to be identical at grid points in the interior of the solution domain. However, results obtained are different, unless a special boundary treatment is used with the LOD method. Then the LOD method is more efficient. Some numerical tests are presented for both cases, and accuracy and Central Processor (CP) time needed for the nonlocal problem are found to be superior than those for the method of Cannon et al. [Cannon et al., Appl Anal J 50, 1993, 1–19]. © 1999 John Wiley & Sons, Inc. Numer Methods Partial Differential Eq 15: 521–534, 1999

Two different explicit finite difference schemes for the numerical solution of the diffusion equation on a rectangular region, subject to local or nonlocal boundary conditions, the latter involving a double integral to simulate specification of mass in a curved region, are compared. These schemes, the two‐dimensional 9‐point Forward Time Centered Space (FTCS) explicit formula [Noye & Hayman, J Comp Math 42, 1992, 223–236] and the locally one‐dimensional (LOD) method based on the classical one‐dimensional FTCS formula [Noye & Hayman, J Comp Math 51, 1994, 215–228], are economical to use, are generally second‐order, have bounded ranges of stability, and can be shown to be identical at grid points in the interior of the solution domain. However, results obtained are different, unless a special boundary treatment is used with the LOD method. Then the LOD method is more efficient. Some numerical tests are presented for both cases, and accuracy and Central Processor (CP) time needed for the nonlocal problem are found to be superior than those for the method of Cannon et al. [Cannon et al., Appl Anal J 50, 1993, 1–19]. © 1999 John Wiley & Sons, Inc. Numer Methods Partial Differential Eq 15: 521–534, 1999

This work describes the results of a numerical study of buoyancy-driven flow in a stairwell model. Direct comparisons with the experimental data have been presented. The model is based on the conservation equations of mass, momentum, and energy and the transport equations of turbulence energy and its rate of dissipation. Two different wall thermal boundary conditions, namely, temperature and heat flux, are used and the results are compared. In the case of the heat flux boundary condition, only the convective component of the heat flux at each wall has been used, by first calculating the radiative component and then separating it from the total heat flux. The numerical model predicts the overall features of the flow satisfactorily, and the details of the velocity and temperature field with reasonable accuracy.

The scattering and diffraction of SH waves by arbitrarily-located multiple planar cracks in an anisotropic half-space is considered. The problem is formulated in terms of a system of Hadamard finite-part singular (hyper-singular) integral equations which can be solved numerically using collocation techniques.

This paper describes an experimental study of two-phase “bubble-droplets” of butane in distilled water. In the process of direct-contact heat transfer between two immiscible liquids, and with change of phase, evaporation occurs within a liquid droplet to form an interior bubble which ultimately may expand to absorb the entire droplet. The so-called “stopped-evaporation” two-phase bubble-droplets were formed by such evaporating droplets of butane rising in a column of water by application of pressure on the surface of the water to stop the evaporation. The configurations of such bubble-droplets, which depend on the ratio of mass of the vapor to mass of the liquid, are discussed. Results are also given for the rise velocity, and comparisons are made between the rise velocity of stopped-evaporation droplets and those of evaporating droplets.

A new second-order finite difference technique based upon the Peaceman and Rachford (P - R) alternating direction implicit (ADI) scheme, and also a fourth-order finite difference scheme based on the Mitchell and Fairweather (M - F) ADI method, are used as the basis to solve the two-dimensional time dependent diffusion equation with non-local boundary conditions. The results of numerical experiments for these new methods are presented. These schemes use less central processor time (CPU) than a second-order fully implicit scheme based on the classical backward time centered space (BTCS) method for two-dimensional diffusion. They also have a larger range of stability than a second-order fully explicit scheme based on the classical forward time centered space (FTCS) method.

The dynamics and the associated heat transfer process of butane droplets evaporating in water are investigated experimentally. New data are presented for the instantaneous growth, rise velocity and the heat transfer coefficient. The behaviour of the bubble-droplet, from the initial to the final stages of evaporation, is divided into four regions and is described with reference to similarities with the behaviour of a spherical droplet, spheroidal bubble-droplet, large spheroidal bubble and spherical cap bubble. The equations which represent the results for the heat transfer coefficient are given.

We introduce and present the general solution of three two-term fractional differential equations of mixed Caputo/Riemann–Liouville type. We then solve a Dirichlet type Sturm–Liouville eigenvalue problem for a fractional differential equation derived from a special composition of a Caputo and a Riemann–Liouville operator on a finite interval where the boundary conditions are induced by evaluating Riemann–Liouville integrals at those end-points. For each 1/2<α<1it is shown that there is a finite number of real eigenvalues, an infinite number of non-real eigenvalues, that the number of such real eigenvalues grows without bound as α→1-, and that the fractional operator converges to an ordinary two term Sturm–Liouville operator as α→1-with Dirichlet boundary conditions. Finally, two-sided estimates as to their location are provided as is their asymptotic behavior as a function of α.

A method for solving the nonlinear second-order Fredholm integro-differential equations is presented. The approach is based on a compactly supported linear semiorthogonal B-spline wavelets. The operational matrices of derivative for B-spline scaling functions and wavelets are presented and utilized to reduce the solution of Fredholm integro-differential to the solution of algebraic equations. Illustrative examples are included to demonstrate the validity and applicability of the technique.

Compactly supported linear semiorthogonal B-spline wavelets together with their dual wavelets are developed to approximate the solutions of nonlinear Fredholm-Hammerstein integral equations. Properties of these wavelets are first presented; these properties are then utilized to reduce the computation of integral equations to some algebraic equations. The method is computationally attractive, and applications are demonstrated through an illustrative example.