the theory of contact mechanics deals with stresses and deformations which arise when the surfaces of two solid bodies are brought into contact. in elastic deformation contact occurs over a finite area. a regular method for determining the dimensions of this area is hertz contact model. appearance of atomic force microscope results in introduction of contact mechanics into biology. low elastici...

A centromere (CEN) in Saccharomyces cerevisiae consists of approximately 150 bp of DNA and contains 3 conserved sequence elements: a high A + T region 78-86 bp in length (element II), flanked on the left by a conserved 8-bp element I sequence (PuTCACPuTG), and on the right by a conserved 25-bp element III sequence. We have carried out a structure-function analysis of the element I and II region...

Respiration is an essential element in operatic singing performance, providing the singer support for the proper production of tone. However, respiration can also serve as an expressive element in the communication of dramatic ideas, creating an emotional subtext to the expressive intentionality of the piece. Previous research supports the relationship between respiration and dramatic intention...

background: the human body gets fluorine from a variety of sources including food and water. this element is essential in order to prevent tooth decay. however, high concentrations of this element led to a lot of dental fluorosis and skeletal injuries. this study aimed to measure the concentration of fluoride in water and tea consumed in the city of qom. methods: the present study is cross-sect...

RNA editing in higher plant plastids alters mRNA sequences by C-to-U conversions at highly specific sites through an unknown mechanism. To elucidate how the cytidine residues to be edited are specifically recognized and distinguished from other cytidines in close proximity, we have changed in vivo the distances of two plastid RNA-editing sites from their essential upstream cis-acting sequence e...

Pasture established on polluted soil may pose a risk to grazing livestock creating a requirement for mechanical management which may affect biodiversity and expend energy. The risk associated with managing pasture by grazing horses (non-edible livestock) is being assessed in the Guadiamar Valley (SW Spain), where soils are polluted with trace elements following a major pollution incident. Soil ...

We show that in a local S1 ring every two-generated ideal of linear type can be generated by a two-element sequence of linear type and give an example which illustrates that the S1 condition is essential. We also show that every Noetherian local ring in which every two-element sequence is of linear type is an integrally closed integral domain and every two-generated ideal of it can be generated...

In this paper, free and forced vibration analysis of functionally graded material cylinders was carried out by mesh-free and finite element method. In this analysis, MLS shape functions are used for approximation of displacement field in the weak form of motion equation and essential boundary conditions are imposed by transformation method. Resulted set of differential equations are solved usin...