Transaction processing speed is one of the major considerations in cryptocurrencies that are based on proof of work (POW) such as Bitcoin. At an intuitive level it is widely understood that processing speed is at odds with the security aspects of the underlying POW based consensus mechanism of such protocols, nevertheless the tradeo between the two properties is still not well understood. In th...

Empirical work on cross-country growth has focussed almost exclusively on the speed of convergence to steady state and the variations in steady state levels. This paper examines the estimated long-run growth rate, i.e. the rate of steady state growth, in a Solow growth model. All estimates of common world steady state growth are shown to be zero or significantly negative under the null model. T...

Several studies have demonstrated that poor early nutrition, followed by growth compensation, can have negative consequences later in life. However, it remains unclear whether this is attributable to the nutritional deficit itself or a cost of compensatory growth. This distinction is important to our understanding both of the proximate and ultimate factors that shape growth trajectories and of ...

BACKGROUND Zebrafish has been largely accepted as a vertebrate multidisciplinary model but its usefulness as a model for exercise physiology has been hampered by the scarce knowledge on its swimming economy, optimal swimming speeds and cost of transport. Therefore, we have performed individual and group-wise swimming experiments to quantify swimming economy and to demonstrate the exercise effec...

A ­ nite-element method is developed for determining the critical sliding speed for thermoelastic instability of an axisymmetric clutch or brake. Linear perturbations on the constant-speed solution are sought that vary sinusoidally in the circumferential direction and grow exponentially in time. These factors cancel in the governing thermoelastic and heat-conduction equations, leading to a line...

BACKGROUND Gait acquisition is supported by changes in the neuromusculoskeletal system of the child. Changes in the dimensions of the body structures resulting from the growth of the child partly explain gait improvement in the first year of life. OBJECTIVES To evaluate whether changes in body mass and leg length modulate the effect of independent gait practice (experience) on gait speed and ...

A computational approach to the optimization of fracture resistance of multiphase materials (here high speed steels) by varying their microstructure is presented. The main points of the optimization of steels are as folIows: (1) development and verification of the model: numerical simulation of crack initiation and growth in real microstructures of steels, (2) computational experiment: simulati...

Experiments were conducted to measure the dendrite tip growth velocities of equiaxed dendritic crystals settling in an undercooled succinonitrile (SCN)-acetone melt. The tip velocities were measured as a function of the settling speed of the crystal and the Eulerian angle between the dendrite arms and the flow direction relative to the crystal. The average of the measured tip growth velocities ...

to evaluate the effect of different application methods of different strains of pgpr on sorghum forage production, a field experiment was conducted in research farm of college of agriculture of university of tehran in karaj during 2009. the treatments were arranged factorially and the data was analyzed based on a complete block design with three replications. the treatments comprised of three p...