Gap junctions, which are essential for functional coordination and homeostasis within tissues, permit the direct intercellular exchange of small molecules. The abundance and diversity of this exchange depends on the number and selectivity of the comprising channels and on the transjunctional gradient for and chemical character of the permeant molecules. Limited knowledge of functionally signifi...

The webpage of Herbert Wilf describes eight Unsolved Problems. Here, we completely resolve the third of these eight problems. The task seems innocent: find the first term of the asymptotic behavior of the coefficients of an ordinary generating function, whose coefficients naturally yield rational approximations to π. Upon closer examination, however, the analysis is fraught with difficulties. F...

The present paper looks at the implications of anticipated changes in population size and composition for the projected number of deaths from natural disasters Building on empirical evidence from cross-country time series of factors associated with natural disaster fatalities since 1970 in 174 countries, the paper first highlights the major role of education in enabling people to cope with weat...

Cast, coarse-grained Al-Sc alloys are interesting candidates for high temperature, creepresistant applications due to the formation of a high number density of nanometer sized Al3Sc precipitates [1]. Upon addition of Yb to Al-Sc alloys, Yb replaces the Sc forming Al3(Sc1-xYbx) precipitates (L12 structure) [2]. The resulting alloys have higher creep resistance due to the larger lattice parameter...

Fe2O3-Al2O3 compounds with different Fe/Al compositions were synthesized by coprecipitation (CP) method and calcined at 300°-1000°C. The formation of crystalline phases (e.g., maghemite, hematite), transformation temperature, specific surface area, lattice parameter, crystallite size, magnetic properties of iron oxide were all affected by the component ratio and thermal treatment.

We have studied the lattice parameter changes of L10 FePt nanoparticles annealed to near equilibrium as a function of composition by x-ray diffraction. We have found that the ~111! diffraction peak shifts linearly with composition, however, the c parameter mostly changes in the Pt rich compositions and the a parameter mostly changes in the Fe rich compositions with respect to the equiatomic com...

In 20 consecutive perfused heart experiments, the electrocardiograms and inductocardiograms of the isolated heart were found unchanged for periods of 4 hours or more. Subsequent expansion of our laboratory facilities made it necessary to rebuild our perfusion apparatus. After this, over 50 successive perfusions proved to be unsuccessful. Premature cardiac arrest and ventricular fibrillation occ...

We establish the limiting distribution of the number Tn of random functions on a set of size n which must be composed before a constant function results. In more detail, let f1, f2, . . . be independent draws from the uniform distribution over all functions from {1, . . . , n} into itself. For t = 1, 2, . . . let gt := ft ◦ · · · ◦ f2 ◦ f1 denote the composition of the first t random maps, and ...

In the presented paper, the governing equations of a vibratory beam with moderately large deflection are derived using the first order shear deformation theory. The beam is homogenous, isotropic and it is subjected to the dynamic transverse and axial loads. The kinematic of the problem is according to the Von-Karman strain-displacement relations and the Hook's law is used as the constitutive eq...

Abstract: In the present work, effect of the nucleating agent such as TiO2, ZrO2, P2O5, Ye2O3 and CeO2 in single, double, triple and fourth systems on the crystallization behavior of various compositions was studied. Using differential thermal analysis (DTA), the composition of Li2O-Al2O3-SiO2 (LAS) was optimized and the coefficient of thermal expansion (CTE), three point flexural strength, har...