objectives: the aim of this study was to evaluate the effect of six herbal teas on the color stability of two types of nanohybrid and one microhybrid resin composite.  materials and methods: 70 disc-shaped specimens, 210 in total (7*2mm), were fabricated from each of the following materials in metal mould : tetric n ceram, grandio, gradia direct anterior. specimens were stored in distilled wate...

abstract urban neighborhoods are as the smallest unit of spatial organization in the city to urban stability. neighborhoods development will be considered one of the main goals of planning the urban stability development and, it is key action to achieve stable development. stable community development perspective, will strengthen the new approach, that the solving of the urban problems is perce...

in the past, rock slope stability analysis were performed either graphically or using a hand-held calculator, but nowadays there are variety of slope stability analysis which can be used according to the field condition and potential failure mode. in 2-d analysis, effect of convex and concave walls are neglected, however concave slopes are believed to be more stable than straight walls due to t...

the occurrence of genotype × environment (ge) interaction has led to the development of several stabilityparameters that can be used to estimate the stability of cultivar performance. repeatability of 20 parametric and non-parametric stability measures across years and yield subsets as well as their association with mean seed yield and interrelationship among them in safflower (carthamus tincto...

eight faba bean genotypes and one local (barkat) as control were evaluated for three successive years (2000-2003) in a randomized complete block design (rcbd) with four replications at gorgan agricultural research station. this study was carried out to determine the morphological traits, yield components and yield stability to select the best genotypes. simple and combined analysis of variance ...

We consider Jackson queueing networks with finite buffer constraints (JQN) and analyze the efficiency of sampling from their stationary distribution. In the context of exact sampling, the monotonicity structure of JQNs ensures that such efficiency is of the order of the coupling time (or meeting time) of two extremal sample paths. In the context of approximate sampling, it is given by the mixin...

in order to study genotype  environment interaction (g  e) and to identify high yielding and stable genotypes, 17 safflower (carthamus tinctorius l.) genotypes were evaluated in a randomized complete block design with 3 replications, at 9 research stations during four consecutive cropping seasons (2003–06) under rainfed conditions. on the basis of ammi analysis of variance, effects of genotyp...

In recent years, many efforts have been made to isolate enzymes from extremophilic organisms in the hope to unravel the structural basis for hyperstability and to obtain hyperstable biocatalysts. Here we show how a moderately stable enzyme (a thermolysin-like protease from Bacillus stearothermophilus, TLP-ste) can be made hyperstable by a limited number of mutations. The mutational strategy inc...

stability and performance are two main issues in motion of bipeds. to ensure stability of motion, a biped needs to follow specific pattern to comply with a stability criterion such as zero moment point. however, there are infinity many patterns of motion which ensure stability, so one might think of achieving better performance by choosing proper parameters of motion. step length and step perio...

The ground truth for cascading failure in power system can only be obtained through a detailed dynamic model involving nonlinear differential and algebraic equations whose solution process is computationally expensive. This has prohibited adoption of such models simulation. To solve this, we propose fast simulation approach based on implicit Backward Euler method (BEM) with stiff decay property...