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This article examines the flow and heat transfer of water and ethylene glycol based copper nanoparticles between two parallel squeezing disks with suction/injection effects. Since metallic particles are strongly influence by magnetic field so we have considered MHD effect that is normal to the surface and lower disk is considered to be permeable. Based upon fundamental law of momentum and energy equation, model is constructed in the form of partial differential equations in cylindrical coordinate system. Fully developed mathematical model is carried out in the form of partial differential equation are then transformed into nonlinear ordinary differential equations. These resulting equations depend upon suction/injection parameter A , Hartmann number M , squeezing number S , and nanoparticle volume fraction ϕ are then solved numerically with Runge–Kutta–Fehlberg (RKF) method. Results are examined via velocity and temperature profile for each Cu -ethylene glycol and Cu -water nanofluid. To analyze the flow and heat transfer behavior at the surface, results are plotted for skin friction and local Nusselt number. It is finally concluded that skin friction coefficient attained from Cu -water remain higher than Cu -ethylene glycol, however this observation is quite opposite for local Nusselt number. [ABSTRACT FROM AUTHOR]

Influence of magnetic field for metachoronical beating of cilia for nanofluid with Newtonian heating in an asymmetric channel is considered. The governing coupled equations are constructed under long wavelength and low Reynold's number approximation. The Newtonian heating is controlled by a dimensionless conjugate parameter, which varies between walls of channel. Numerical solutions are evaluated for nanoparticle fraction, heat transfer, stream function and pressure gradient. The important findings in this study are the variation of the conjugate parameter for Newtonian heating γ , Hartmann number M , thermophoresis parameter N t and Brownian motion parameter N b on pressure rise, nanoparticle fraction, heat transfer phenomena, pressure gradient and streamlines. The velocity field increases due to increase in M near the channel walls while velocity field decreases at the centre of the channel. [ABSTRACT FROM AUTHOR]

In this article, we investigate steady triple convective-diffusive boundary layer free convection flow past a vertical flat plate embedded in a porous medium filled by a water-based nanofluid and two salts. The plate is assumed to be convectively cooled by a surrounding fluid. It is assumed that there is no nanoparticle flux at the surface and the effect of thermophoresis is taken in to account in the boundary condition. The effects of Brownian motion and thermophoresis parameters are also introduced through a Buongiorno model in the governing equations. The self-similar solutions are obtained numerically using an implicit finite difference method. The effects of the buoyancy ratio, regular Lewis numbers and modified Dufour parameters of both salts and nanofluid parameters on the flow and heat transfer are investigated. It is found that the heat transfer rate increases as we include nanoparticles and salts. Furthermore, it is also shown that the Brownian motion has negligible effects on reduced Nusselt number. [ABSTRACT FROM AUTHOR]

In the present article, the consequences of cilia motion are reflected by the MWCNT. The problem is modeled in a symmetric channel with ciliated walls. Exact solutions of the governing flow problem are obtained for pressure gradient, temperature and velocities of the fluid. Streamlines for the velocity profile are plotted to discuss the trapping phenomenon. [ABSTRACT FROM AUTHOR]

In this article, we have discussed inclined magnetic field on the peristaltic flow of biviscosity with the impact of thermal and velocity slips in an irregular channel. The momentum governing equations are fabricated under long wavelength and low Reynolds number guesstimate. Exact solutions are found in closed-form for flow equations representing stream function and pressure gradient. The flow comportment is examined over the properties of the governing parameters such as, the upper limit apparent viscosity coefficient β, slip parameters Λ, γ , Hartmann number M and amplitudes ϕ , a , b and d on pressure rise, velocity, pressure gradient and subsequently on streamlines. [ABSTRACT FROM AUTHOR]

Abstract: The steady triple diffusive boundary layer free convection flow past a horizontal flat plate embedded in a porous medium filled by a water-based nanofluid and two salts is investigated numerically. The plate is assumed to be convectively cooled by a surrounding fluid. It is assumed that there is no nanoparticle flux at the surface and the effect of thermophoresis is taken into account in the boundary condition. The effects of Brownian motion and thermophoresis parameters are also introduced through Buongiorno model in the governing equations. Using appropriate similarity variables, the partial differential equations are transformed to ordinary (similarity) equations, which are then solved numerically using an implicit finite difference method with quasi-linearization technique. The effects of the buoyancy ratio, regular Lewis numbers and modified Dufour parameters of both salts and nanofluid parameters on the flow and heat transfer are investigated. It is found that the heat transfer rate increases as we include nanoparticles and salts. [Copyright &y& Elsevier]

Abstract: Fe-deficient Ni–Cu–Zn ferrites with composition Ni0.28Cu0.10Zn0.62O(Fe2O3)1− x , where x =0.00, 0.02, 0.04, 0.06, and 0.08 were prepared by the double sintering ceramic technique. Real part of the initial permeability μ′, Curie temperature T c, imaginary part of the initial permeability μ″, relative quality factor (Q-factor) of the samples were elaborately discussed as a function of frequency and temperature with increase of Fe-deficiency during the heating and cooling cycles. The temperature dependence of the imaginary part of the complex permeability curves are very interesting to note that there is a peak value of μ″ at particular temperature which corresponds to the T c because at this temperature the samples might be in complete spin disorder. This reflects that at T c, a ferrimagnetically ordered state over comes K B T and becomes comparable with μ 0 H where the loss becomes maximum. Results of heating and cooling cycles were found to be very close to each other. The small difference during heating and cooling process might arise due to the thermal hysteresis which is accumulated in this work. In our study, it was noticed that the resonant frequency and T c increases first with the increase in iron deficiency and decreases after it takes a maximum at x =0.06. [Copyright &y& Elsevier]

Abstract: Laser-induced breakdown spectroscopic (LIBS) technique was used to study the elemental profile of coral skeletons. Apart from calcium and carbon, which are the main elemental constituents of coral skeleton, elements like Sr, Na, Mg, Li, Si, Cu, Ti, K, Mn, Zn, Ba, Mo, Br and Fe were detected in the coral skeletons from the Inani Beach and the Saint Martin’s island of Bangladesh and the coral from the Philippines. In addition to the qualitative analysis, the quantitative analysis of the main elemental constituent, calcium (Ca), was done. The result shows the presence of (36.15±1.43)% by weight of Ca in the coral skeleton collected from the Inani Beach, Cox’s Bazar, Bangladesh. It was determined by using six calibration curves, drawn for six emission lines of Ca I (428.301nm, 428.936nm, 431.865nm, 443.544nm, 443.569nm, and 445.589nm), by standard analyte additive method. Also from AAS measurement the percentage content of Ca in the same sample of coral skeleton obtained was 39.87% by weight which compares fairly well with the result obtained by the analyte additive method. [Copyright &y& Elsevier]

Thermal and flow analysis is performed for natural convection in a porous trapezoidal cavity considering a non-equilibrium thermal energy transport model. The model study comprises a partially and fully heated bottom wall while obstacles are placed inside the cavity to examine the thermal behavior. However, governing energy and momentum equations exhibit an unsteady state, but the numerical outcomes are obtained after employing the steady-state condition. The physical problem is expressed in a mathematical model and numerically simulated using the finite difference scheme. The results are presented in graphical sets, while a comparative tabular analysis with existing literature is also reported. It is demonstrated that the parameters γ and H affect thermal non-equilibrium and that the isotherms and streamlines are symmetrically distributed around the obstacles. The local Nusselt number and average Nusselt numbers show a dominant enhancement for both fluids and solid phases assisted by Rayleigh numbers while decreased with an increase in the heating domains. The reported study will be useful in analyzing the natural convection thermal non-equilibrium models in curvilinear geometries. [ABSTRACT FROM AUTHOR]

The flow and heat transfer in a trapezoidal cavity were investigated numerically. Water-based ferrofluid with Fe 3 O 4 nanoparticles and porous medium with low Darcy number were chosen for the investigation. Both side walls were maintained at a constant cold temperature, the top wall was adiabatic, and the heater is placed at the bottom wall. The dimensionless governing equations are solved numerically using finite element method. A uniform magnetic field of strength B 0 was imposed. It is assumed that the magnetic Reynolds number is much smaller than the induced magnetic field so that it can be neglected when compared to the applied magnetic field. No slip boundary conditions were applied at the walls. The streamlines and isotherms were generated to explain the behaviour of dimensionless velocity and temperature inside the cavity. It is demonstrated that the magnetic field, thermal buoyancy, porous medium permeability and the length of the heating element play a crucial role in the enhancement of dimensionless average heat transfer rate. [ABSTRACT FROM AUTHOR]

Understanding of flow nature inside a close geometry as well as analysis of heat augmentation through fluids has been gaining a vital interest among research community due to industrial and engineering applications. Herein, a model study is conduced to investigate the heat and mass transfer of Magnetohydrodynamic (MHD) flow enclosed a square cavity with top wall is heated. Two heated and two clod square obstacles are placed inside the square cavity. Feasible nondimensional variables are introduced to transform the continuity, momentum and energy equations into nondimensional form. A finite element model is developed and applied to investigate the numerical solutions of nondimensional set of partial differential equations. In order to scrutinize the significant influence of dimensionless parameters on streamlines, isotherms and isoconcentrations simulations are executed when the bottom squares are heated. It is detected that Nusselt numbers increases as enhancing the thermal radiation parameter. Comparison of the achieved results for local and average Nusselt numbers with published results are presented, which are evident that the suggested method is well-matched to examine the solutions of such types of problems and it can be extended for solving diversified problem of physical nature having complex geometry. • MHD natural convection is presented in a square cavities having multiple obstacles. • A finite element model is developed and applied to find the numerical solution. • Simulations are performed against the emerging parameters. • Obtained results for physical parameters mainly for new effects being added. [ABSTRACT FROM AUTHOR]

The focus of the current study is to obtain the dual solutions via simulation for the two dimensional Casson fluid over the stretching sheet. Both the upper and lower branch solutions of the corresponding streamline profiles for the Casson fluid over the stretching sheet are obtained under the influences of the pertinent parameters. Both the steady and unsteady forms of the Casson fluid over the stretching sheet are valuable in performing the sensitivity analysis. Here is the graphical illustrations of the dual solutions for the Casson fluid over the stretching sheet. The aim of the current study is to find out the dual solutions of the two-dimensional magnetohydrodynamic (MHD) flow of Casson fluid and heat transfer over the stretching sheet. The focus of the study is to examine the linear thermal radiation effects on dual solutions for both the steady and unsteady flow of Casson fluid over the stretching sheet under the influence of uniform magnetic field. The governing equations are formed as system of partial differential equations (PDEs). Using suitable transformations, the system of PDEs are converted into favorable nonlinear system of ordinary differential equations (ODEs). Simulations are performed in Maple 2015 to form the dual solutions in order to achieve the velocity, temperature, skin friction and heat transfer profiles of the Casson fluid over the stretching sheet. It is concluded that the dual solutions for the corresponding model are numerically stable. Furthermore, the upper branch solutions of the Casson fluid profiles are numerically stable as compared to the lower branch solutions. Results indicate that positive Eigen values of the MHD flow of Casson fluid provide stable profiles as compared to the negative Eigen values. It is believed that the current study would provide a base for the dual solution of the other types of the non-Newtonian fluid flows over various categories of surfaces. • MHD flow of Casson fluid and heat transfer is analyzed. • Thermal radiation effects on both the steady and unsteady Casson fluid is examined. • Dual nature solutions for the proposed model are found. • The stability of the dual solutions are presented. [ABSTRACT FROM AUTHOR]

This framework is established for alumina and copper-water nanofluid over a shrinking sheet with thermal radiation effect. To determine the better thermal performance of base fluid, model is constructed in the form of effective thermal conductivity and viscosity for nanoparticles. Thermal radiation effects are also incorporated to determine the significant influence of temperature in the restricted domain of the model. Partial differential equations are acquired from momentum and energy equations along with the boundary constraint at the surface. The nonlinear ODEs are further acquired from governing PDEs by using the similarity transformation. Dual nature's results are accomplished in the form of closed form exact solutions. The consequences of various physical parameters on the velocity and temperature profile are investigated along with the assist of tables and graphs. Additionally, temperature undershoot is noticed in some cases. Consequently, the heat absorption on surface arises due to heat transfer from the surface in some situations. In addition, the alumina and copper nanoparticles based fluids tender astounding antimicrobial actions to various gram class microscopic organisms. Some major results affirm that local Nusselt number enhance by increasing the values of thermal radiation parameter for Cu- and Al 2 O 3 -water. In addition, rate of heat transfer is higher for the first solution of both of Al 2 O 3 - and Cu-water. [ABSTRACT FROM AUTHOR]

In this article, combine effects of the inclined magnetic field and velocity slip conditions are analyzed for nanofluid flow over a moving over a flat surface. Two different kind of Carbon nanotubes are also incorporated within the base fluid, namely: Single wall carbon nanotubes (SWCNTs) and multiple wall carbon nanotubes (MWCNTs). Rheological characteristics of CNTs-Water and CNTs-Kerosene are studied under the influence of inclined applied magnetic field between 0 ≤ γ ≤ π /2. Close form solutions are obtained for both momentum and energy equation in the form of hypergeometric function. The core objective of aligned angle magnetic field is to use the governing magnetic intensity on the nanofluid and to extend the appraisals of aligned angle of the magnetic field produce to upgrade the local skin friction and decline the local Nusselt number. Significant consequences of inclined magnetic field with rest of the physical parameters including Hartmann number, velocity slip and solid volume fraction nanoparticles are presented and analyzed via numerical and graphical illustrations. It is found that SWCNTs-kerosene depicts the high friction and heat transfer rate at the surface as compare to the rest of the mixtures. [ABSTRACT FROM AUTHOR]

Present study examines the fully developed squeezing flow of water functionalized magnetite nanoparticles between two parallel disks. For strongly magnetite fluid (water) three different types of nanoparticles having better thermal conductivity: Magnetite (Fe 3 O 4 ), Cobalt ferrite (CoFe 2 O 4 ) and Mn–Zn ferrite (Mn–ZnFe 2 O 4 ) are incorporated within the base fluid (water). Systems of equations containing the nanoparticle volume fraction are rehabilitating in the form of partial differential equations using cylindrical coordinate system. Resulting mathematical model is rehabilitated in the form of ordinary differential equations with the help of compatible similarity transformation. Results are analyzed for velocity, temperature, reduced skin friction and reduced Nusselt number with variation of different emerging parameters and determine the superb thermal conductivity among mentioned nanoparticles. Comparison among each mixture of ferrofluid has been plotted as response to differences in reduced skin friction and reduced Nusselt number distributions. Dominating effects are analyzed for squeezing parameter and it is found that water based-magnetite (Fe 3 O 4 ) gives the highest reduced skin friction and reduced Nusselt number as compared to the rest of the mixtures. Isotherms are also plotted against various values of nanoparticle volume fraction to analyze the temperature distribution within the whole domain of squeezing channel. [ABSTRACT FROM AUTHOR]

This paper investigates the problem of oblique hydromagnetic stagnation point flow of a variable viscosity electrically conducting optically dense viscous incompressible nanofluid over a convectively heated stretching sheet in the presence of thermal radiation. The nanofluid model employed in this study incorporates the effects of Brownian motion and thermophoresis. The governing nonlinear partial differential equations for momentum, energy and nanoparticles concentration are reduced into a set of non-linear ordinary differential equations with the aid of suitable similarity transformations. The transformed equations are numerically integrated using fourth–fifth order Runge–Kutta–Fehlberg method. The effects of various controlling parameters on the dimensionless velocity, temperature, nanoparticles concentration, skin friction, Nusselt and Sherwood numbers are analysed and presented graphically. Obtained numerical results are compared and found to be in good agreement with previously published results as special cases of the present investigation. It is found that non-alignment of the re-attachment point on the sheet surface decreases with an increase in magnetic field intensity. [ABSTRACT FROM AUTHOR]

In this article, flow and heat transfer effects of both single and multiple wall carbon nanotubes within the base fluid (water) are analyzed between two rotating plates. Moreover, we have considered that the upper wall of the channel is permeable while the lower wall is moving with variable velocity to produce the forced convection along with the Coriolis and centripetal forces with the rotation of fluid. The compatible transformations have been used to construct the non-dimensional system of governing equations. Numerical simulation is performed to obtain the solutions structure. Thermophysical properties of each base fluid and nano particle are incorporated in the form of thermal conductivity, viscosity, density, specific heat, nanoparticle volume fraction and Prandtl number to attain the solution of the model. It is found that water based single wall carbon nanotubes (SWCNTs) produce less drag and high heat transfer rate as compared to the water based multiple wall carbon nanotubes (MWCNTs). Influence of rotation causes the drag increase and decreases the Nusselt number irrespective of the other pertinent parameters. Moreover suction/injection plays an important role in determining the peak position of velocity. The effect of suction/injection is shown through plotting streamlines. [ABSTRACT FROM AUTHOR]

The pressure driven peristaltic flow of nanofluid in a curved channel is investigated. The flow exploration demeanors the induced magnetic field. Long wavelength and low Reynolds number approach is followed. Numerical solutions are obtained by employing shooting method. The effects of substantial parameters have been portrayed and discussed on the temperature and mass distributions, stream function, magnetic force function, induced magnetic field and pressure rise per wavelength. [ABSTRACT FROM AUTHOR]

Present study is devoted to analyze the magnetohydrodynamics (MHD) squeezed flow of nanofluid over a sensor surface. Modeling of the problem is based on the geometry and the interaction of three different kinds of metallic nanoparticles namely: copper (Cu), alumina (Al 2 O 3 ) and titanium dioxide (TiO 2 ) with the homogeneous mixture of base fluid (water). The self-similar numerical solutions are presented for the reduced form of the system of coupled ordinary differential equations. The effects of nanoparticles volume friction, permeable velocity and squeezing parameter for the flow and heat transfer within the boundary layer are presented through graphs. Comparison among the solvent are constructed for both skin friction and Nusselt number. Flow behavior of the working nanofluid according to the present geometry has analyzed through Stream lines. Conclusion is drawn on the basis of entire investigation and it is found that in squeezing flow phenomena Cu–water gives the better heat transfer performance as compare with the rest of mixtures. [ABSTRACT FROM AUTHOR]

In the present study, thermal conductivity and viscosity of both single-wall and multiple-wall Carbon Nanotubes (CNT) within the base fluids (water, engine oil and ethylene glycol) of similar volume have been investigated when the fluid is flowing over a stretching surface. The magnetohydrodynamic (MHD) and viscous dissipation effects are also incorporated in the present phenomena. Experimental data consists of thermo-physical properties of each base fluid and CNT have been considered. The mathematical model has been constructed and by employing similarity transformation, system of partial differential equations is rehabilitated into the system of non-linear ordinary differential equations. The results of local skin friction and local Nusselt number are plotted for each base fluid by considering both Single Wall Carbon Nanotube (SWCNT) and Multiple-Wall Carbon Nanotubes (MWCNT). The behavior of fluid flow for water based-SWCNT and MWCNT are analyzed through streamlines. Concluding remarks have been developed on behalf of the whole analysis and it is found that engine oil-based CNT have higher skin friction and heat transfer rate as compared to water and ethylene glycol-based CNT. [ABSTRACT FROM AUTHOR]

The effects of triple diffusion on a horizontal plate immersed in a porous medium are investigated subject to a convective boundary condition. A Darcy model is used to analyze two different scenarios where salts with different compositions are dissolved in a fluid-saturated porous medium. The governing partial differential equations are reduced to ordinary (similarity) differential equations that are solved numerically using an implicit finite difference method with a quasi-linearization technique. Results are compared with the available data and are found to be in excellent agreement. Results of the dimensionless velocity, temperature, salts concentrations, reduced Nusselt and Sherwood numbers are presented for both buoyancy aiding and opposing flows. [ABSTRACT FROM AUTHOR]

Abstract: The combined effects of Navier slip and magnetic field on boundary layer flow with heat and mass transfer of a water-based nanofluid containing gyrotactic microorganisms over a vertical plate are investigated. Using Oberbeck–Boussinesq approximation and similarity transformation, the nonlinear model equations are obtained and tackled numerically to obtain the dimensionless velocity, temperature, nanoparticle concentration and density of motile microorganisms together with the reduced Nusselt, Sherwood and motile microorganism numbers. The present numerical results are compared with available data and are found in an excellent agreement. Pertinent results are presented graphically and discussed quantitatively with respect to variation in the controlling parameters. It is observed that the magnetic field suppresses the dimensionless velocity and increases the dimensionless temperature inside the boundary layers. The bioconvection parameters tend to reduce the concentration of the rescaled density of motile microorganisms. It is also found that the reduced Nusselt, Sherwood and density numbers of microorganisms depend strongly upon the magnetic, buoyancy, nanofluid and bioconvection parameters. [Copyright &y& Elsevier]

Abstract: LIBS technique coupled with adsorption has been applied for the efficient detection of arsenic in liquid. Several adsorbents like tea leaves, bamboo slice, charcoal and zinc oxide have been used to enable sensitive detection of arsenic presence in water using LIBS. Among these, zinc oxide and charcoal show the better results. The detection limits for arsenic in water were 1ppm and 8ppm, respectively, when ZnO and charcoal were used as adsorbents of arsenic. To date, the determination of 1ppm of As in water is the lowest concentration of detected arsenic in water by the LIBS technique. The detection limit of As was lowered to even less than 100ppb by a combination of LIBS technique, adsorption by ZnO and concentration enhancement technique. Using the combination of these three techniques the ultimate concentration of arsenic was found to be 0.083ppm (83ppb) for arsenic polluted water collected from a tube-well of Farajikandi union (longitude 90.64°, latitude 23.338° north) of Matlab Upozila of Chandpur district in Bangladesh. This result compares fairly well with the finding of arsenic concentration of 0.078ppm in the sample by the AAS technique at the Bangladesh Council of Scientific and Industrial Research (BCSIR) lab. Such a low detection limit (1ppm) of trace elements in liquid matrix has significantly enhanced the scope of LIBS as an analytical tool. [Copyright &y& Elsevier]

Abstract: This paper analyzes the combined effects of buoyancy force, convective heating, Brownian motion, thermophoresis and magnetic field on stagnation point flow and heat transfer due to nanofluid flow towards a stretching sheet. The governing nonlinear partial differential equations are transformed into a system of coupled nonlinear ordinary differential equations using similarity transformations and then tackled numerically using the Runge–Kutta fourth order method with shooting technique. Numerical results are obtained for dimensionless velocity, temperature, nanoparticle volume fraction, as well as the skin friction, local Nusselt and Sherwood numbers. The results indicate that dual solutions exist for shrinking case. The effects of various controlling parameters on these quantities are investigated. It is found that both the skin friction coefficient and the local Sherwood number decrease while the local Nusselt number increases with increasing intensity of buoyancy force. [Copyright &y& Elsevier]

In this article, we are reporting the mechanism of natural convection flow in a partially heated trapezoidal cavity containing non-Newtonian Casson fluid. A non-Newtonian model of Casson fluid is used to develop the governing flow equations. The thermal control inside the enclosure is managed using the partially heated lower wall. Most physical and significant conditions are used at the inclined walls of the cavity to attain the performance of heat management and streamlines. The Galerkin finite element technique (GFEM) is adopted to examine the solution of dimensionless PDEs system. The thermal and flow fields are envisioned through isotherms and streamlines while the simulations are performed for flow and thermal fields via various ranges of Rayleigh number (104 ≤ Ra ≤ 105.5), and different lengths of the heated part. Furthermore, outcomes are visualized for Nusselt number over the cavity wall under the influence of the Casson parameter. It is observed that as Casson fluid parameter decreases the velocities in x -direction and y -direction exhibit the dominant behavior. The influence of lower values of Casson fluid parameter on Nusselt number is significant at the middle of the cavity while the Nusselt number increases as increases the heated bottom wall in length. The purpose of the present article is to investigate the thermal management and natural convection flow in a partially heated trapezoidal cavity filled with Casson fluid. The simulations has been performed for various values of the Rayleigh number and the governing parameters. Unlabelled Image [ABSTRACT FROM AUTHOR]

This paper deals with a problem where the effect of variable magnetic field and chemical reaction on free convective flow of an electrically conducting incompressible water based nanofluid over an exponentially stretching sheet has been investigated. In the present study, Buongiorno model associated with Brownian motion and thermophoretic diffusion is employed to describe the heat transfer enhancement of nanofluids. Some suitable similarity transformations reduced the governing boundary layer non-linear partial differential equations into a set of ordinary non-linear differential equations. The transformed equations are then solved numerically using fourth order Runga-Kutta method along with Shooting technique. The major outcomes of the present study is that the magnetic field impedes the fluid motion while thermal as well as mass buoyancy forces accelerate it, the thermophoretic diffusion enhances dimensionless fluid temperature as well as concentration leading to thicker thermal and concentration boundary layers. On the other hand, concentration exponent, Brownian motion parameter and chemical reaction parameter exhibit reverse trend on temperature and concentration. In addition, the presence of magnetic field under the influence of thermal as well as mass buoyancies supports to reduce the rate of heat transfer as well as wall shear stress while the first order chemical reaction develops a thinner concentration boundary layer. [ABSTRACT FROM AUTHOR]

The northern Bay of Bengal is home to some of the deadliest cyclones recorded during the last decades. Storm surge models developed for this region significantly improved in recent years, but they still fail to predict patterns of coastal flooding with sufficient accuracy. In the present paper, we make use of a state-of-the art numerical modeling system with improved bathymetric and topographic data to identify the strengths, weaknesses, and to suggest areas for improvement of current storm surge models in this area. The new model is found to perform relatively well in reproducing waves characteristics and maximum water levels for the two extreme cyclones studied here: Phailin (2013) and Sidr (2007). The wave setup turns out to be small compared to the wind-driven surge, although it still plays a significant role for inland flooding. Relatively large tide-surge interactions mainly due to shallow water effects are also evidenced by the model. These findings plead in favor of further efforts to improve the representation of the bathymetry, especially in the nearshore area, and the implementation of models including tides and radiation stresses explicitly. The main limit of the model is its inability to predict the detailed patterns of coastal flooding satisfactorily. The reason lies mainly in the fact that topographic data also need to be further improved. In particular, a good knowledge of embankments characteristics (crest elevation and their condition) is found to be of primary importance to represent inland flooding correctly. Public authorities should take urgent action to ensure that better data are available to the scientific community, so that state-of-the-art storm surge models reaching a sufficiently high level of confidence can be used for emergency preparedness and to implement mitigation strategies in the northern Bay of Bengal. [ABSTRACT FROM AUTHOR]

[Display omitted] • Large scale polder development has disrupted tidal dynamics in the GBD. • We identify-two persistent positive feedback mechanisms driving these changes. • These feedbacks lead to large impact and long response timescales. • Polder development led to rising high waters, channel capture, and bank erosion. At a global scale, intertidal areas are being reclaimed for agriculture as well as urban expansion, imposing high human pressure on the coastal zone. The Ganges-Brahmaputra Delta (GBD) is an exponent of this development. In this delta, land reclamation accelerated in the 1960's to 1980's, when polders were constructed in areas subject to regular marine flooding. A comprehensive analysis of tidal channel evolution in the southwest GBD reveals how land reclamation leads to tidal amplification, channel shoaling, bank erosion, and interaction between channels in which one tidal river captures the storage area of a neighbouring river. We identify-two positive feedback mechanisms that govern these morphological changes. First, reclaiming intertidal areas results in immediate loss of tidal storage, which leads to amplification and faster propagation of the tides. In systems with abundant sediment supply, the blind tidal channels progressively fill in with sediment, leading to a continued loss of tidal storage and therefore further distorting the tides. Secondly, when intertidal areas of parallel (and inter-connected) river delta distributaries are asynchronously or unevenly reclaimed, one channel distributary may expand its intertidal area at the expense of the other. This is initiated by an increasing propagation speed of the tidal wave in the partially reclaimed distributary, travelling into the non-reclaimed distributary through connecting channels. These connecting channels progressively expand while the pristine channel shoals, and potentially degenerates. Both positive feedback loops are very stable and are responsible for pluvial flooding of polders, large-scale bank erosion, and poorly navigable primary waterways, including the navigation channel accessing Bangladesh's second-largest port. Interventions aiming to solve these problems have to account for the complex positive feedback mechanisms identified in this paper and be nature-based and holistic. [ABSTRACT FROM AUTHOR]

A theoretical investigation of magnetohydrodynamic (MHD) flow and heat transfer of electrically-conducting viscoplastic fluids through a channel is conducted. The robust Casson model is implemented to simulate viscoplastic behavior of fluids. The external magnetic field is oblique to the fluid flow direction. Viscous dissipation effects are included. The flow is controlled by the metachronal wave propagation generated by cilia beating on the inner walls of the channel. The mathematical formulation is based on deformation in longitudinal and transverse velocity components induced by the ciliary beating phenomenon with cilia assumed to follow elliptic trajectories. The model also features velocity and thermal slip boundary conditions. Closed-form solutions to the non-dimensional boundary value problem are obtained under physiological limitations of low Reynolds number and large wavelength. The influence of key hydrodynamic and thermo-physical parameters i.e. Hartmann (magnetic) number, Casson (viscoplastic) fluid parameter, thermal slip parameter and velocity slip parameter on flow characteristics are investigated. A comparative study is also made with Newtonian fluids (corresponding to massive values of plastic viscosity). Stream lines are plotted to visualize trapping phenomenon. The computations reveal that velocity increases with increasing the magnitude of Hartmann number near the channel walls whereas in the core flow region (center of the channel) significant deceleration is observed. Temperature is elevated with greater Casson parameter, Hartmann number, velocity slip, eccentricity parameter, thermal slip and also Brinkmann (dissipation) number. Furthermore greater Casson parameter is found to elevate the quantity and size of the trapped bolus. In the pumping region, the pressure rise is reduced with greater Hartmann number, velocity slip, and wave number whereas it is enhanced with greater cilia length. [ABSTRACT FROM AUTHOR]

WILKES E.A., SELBY A.L., COLE A.T., FREEMAN J.G., RENNIE M.J. & KHAN Z.H. (2011) European Journal of Cancer Care 20, 593-600 Poor tolerability of thalidomide in end-stage oesophageal cancer Oesophageal cancer cachexia is a significant clinical problem, resulting in excessive morbidity and mortality. In a pilot study, 10 patients with cachexia due to advanced cancer of the oesophagus gained weight, including lean tissue, after 14-day treatment with thalidomide. Here, we present randomised placebo controlled trial data over a 6-week period to test the hypothesis that thalidomide is superior to placebo in terms of weight gain in patients with cachexia caused by oesophageal cancer. Thalidomide, 200 mg daily, or an identical placebo was given to patients with advanced oesophageal cancer. Total body weight and lean body mass were assessed in addition to drug tolerability and performance indices. Thirty-four patients were recruited. Of these, six given thalidomide and 16 given placebo completed the protocol; all withdrawals were due to adverse drug reactions or complications of disease. Thalidomide showed no benefit over placebo in participants who completed the protocol. These data suggest that thalidomide is poorly tolerated in patients with advanced cancer of the oesophagus and may not ameliorate the progression of cachexia. In the absence of hard supportive evidence, off-licence treatment with thalidomide should be used with great caution as an adjunct to nutritional support in patients with advanced cancer. [ABSTRACT FROM AUTHOR]

Abstract: Laser-induced breakdown spectroscopy (LIBS) is an emerging and promising tool for rapid and efficient elemental analysis. We used the LIBS technique to analyze the raw monazite sands collected from the beaches in southern Bangladesh. We have detected a number of rare earths (lanthanides) such as cerium, lanthanum, praseodymium, neodymium, yttrium, ytterbium, gadolinium, dysprosium and erbium, in addition to other metallic elements such as zirconium, chromium, titanium, magnesium, manganese, niobium and aluminum. To the best of our knowledge, this is the first time multiple rare earths have been identified in a natural mineral by LIBS. [ABSTRACT FROM AUTHOR]