Combining aqueous multiphase systems (AMPS) and magnetic levitation (MagLev) provides a method to produce hybrid gradients in apparent density. AMPS—solutions of different polymers, salts, or surfactants that spontaneously separate into immiscible but predominantly aqueous phases—offer thermodynamically stable steps in density that can be tuned by the concentration of solutes. MagLev—the levita...

A small salt gradient solar pond with an average surface area of 1.8 m2 and depth of 0.8m has been tested. The depths of storage, gradient and surface zones are 0.3, 0.27 and 0.07m, respectively. The temperature of the storage zone for the summer days reaches its maximum of 65˚ C after about 8 days. Daily variation of the storage zone temperature was about 8˚C which is due to small volume of th...

Convergence problems of meta-GGA (generalized gradient approximation) XC (exchange and correlation) functionals containing a self-interaction correction term are traced back to a singularity of the latter that occurs at critical points of the electron density. This is demonstrated for the bond critical point of equilibrium and stretched H2. A simple remedy is suggested that cures meta-XC functi...

BACKGROUND There are few studies on age and sex-specific asthma prevalence in the age range 1-6 years. The purpose of this report was to estimate age and sex specific asthma prevalence in preschool children and to analyse the influence of possible demographic and geographic determinants. METHODS All 70 allergen avoidance day-care centres and 140 matched ordinary day-care centres across Sweden...

We use the variational quantum Monte Carlo method to calculate the density-functional exchange-correlation hole n(xc), the exchange-correlation energy density e(xc), and the total exchange-correlation energy E(xc) of several strongly inhomogeneous electron gas systems. We compare our results with the local density approximation and the generalized gradient approximation. It is found that the no...

We consider a model, given by two interacting electrons in an external harmonic potential, that can be solved analytically for a discrete and infinite set of values of the spring constant. The knowledge of the exact electronic density allows us to construct the exact exchangtiorrelation potential and exchange-correlation energy by inverting the Kohn-Sham equation. The exact exchange-correlation...

In this work, a simple and versatile microfluidic cell density gradient generator was successfully developed for cytotoxicity of quantum dots (QDs) assay. The microfluidic cell density gradient generator is composed of eight parallel channels which are respectively surrounded by 1-8 microwells with optimized length and width. The cells fall into microwells by gravity and the cell densities are ...

the present study was conducted in the rangeland of glandrood watershed in the province of mazandaran. the objective of this study was to compare between the ecological amplitude of festuca ovina l., and poa bulbosa l., using the function hof along the gradient of the environmental variables. for this purpose 150 plots of 1m2 were established along the altitude gradient. the sampling method was...

OBJECTIVE This study aimed to assess and compare sperm motility, concentration, and morphology recovery rates, before and after processing through sperm washing followed by swim-up or discontinuous density gradient centrifugation in normospermic individuals. METHODS Fifty-eight semen samples were used in double intrauterine insemination procedures; 17 samples (group 1) were prepared with sper...