bipolar cardiac electrograms were obtained in dogs from ischemic areas following temporary coronary artery ligation. characteristic alterations from the controls were observed, including increase in dura tion, decrease in amplitude and alterations in configuration. these changes were found to be completely reversible upon restoration of coronary flow. the bipolar electrogram has been recommende...

Precisely describing the formation and evolution rules of coal-rock fracturing crack have great value on reservoir fracturing improvement and highly efficient mining of coal bed methane well. In this paper, a non-linear dynamic method is used to study crack damage evolution behavior of coal-rock fracturing. Considering distribution characteristics of natural cracks in coal-rock, and based on da...

During the flood development in an oil field, the creep characteristic of mudstone is one of the important factors causing casing damage. In this study, based on the theory of fractional order differential and taking into account the creep damage evolution rules, a fractional nonlinear creep-damage model is proposed to reflect the instantaneous deformation in loading processes and the accelerat...

The present study utilizes an analytical method to formulate the three lowest modal frequencies of axially-loaded notched beam through both crack location and load level in a specific format that can be used in existing frequency-based crack-identification methods. The proposed formula provides a basis to shift into two states, one with axial loading and the other without any loading whatsoever...

asafoetida is the dried latex exuded from the living underground rhizome or tap root of ferula assafoetida. antibacterial characteristic of asafoetida was shown using the circular zone diameter of bacterial growth inhibition by disk-diffusion method on two gram positive and three gram negative bacteria. then, the bacterial genomic dna damage, induced by f. assafoetida latex, was demonstrated us...

Evolution of microdamage in advanced composites was experimentally studied in this paper. A new method of acoustic emission (AE) analysis of histories of different damage mechanisms was formulated based on a combination of transient AE classification and multiparameter filtering. The capabilities of the method were illustrated on examples of damage evolution in several graphite/epoxy composites...