Abstract: The governing equations of motion for a drill string considering coupling between axial, lateral and torsional vibrations are obtained using a Lagrangian approach. The result leads to a set of non-linear equations with time varying coefficients. A fully coupled model for axial, lateral, and torsional vibrations of drill strings is presented. The bit/formation interactions are assumed ...

Statins are most effective pharmacologically agents to decrease total plasma cholesterol level by competitive inhibition of HMG-Co A reductase. Apart from the well-known LDL and cholesterol lowering effect, statins have been postulated to exert other beneficial effects also called pleotropic or non-lipid effects. Better understanding of various pleotropic effects of statins has prompted a new s...

Background: Childhood/adolescence under- and over-nutrition are among the major public concerns worldwide. This study aimed to determine the prevalence of underweight, overweight, and obesity among children living in Yazd, Iran using different criteria. Methods: This community-based cross-sectional study was conducted among children and adolescents aged 6-18 years. Body weight, height, waist, a...

nevoid basal cell carcinoma syndrome (bcns) is an autosomal dominant inherited disorder. multiple organ systems may be affected in this syndrome including abnormalities of the skin, skeletal system, genitourinary system and central nevus system. in this report, we present a case of nevoid basal cell carcinoma syndrome in a 26-year-old male patient. the patient had multiple odontogenic keratocys...

In this paper, surface and piezoelectric effects on the vibration behavior of nanowires (NWs) are investigated by using a Timoshenko beam model. The electric field equations and the governing equations of motion for the piezoelectric NWs are derived with the consideration of surface effects. By the exact solution of the governing equations, an expression for the natural frequencies of NWs with ...

The fifth revision of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) was the most controversial in the manual's history. This review selectively surveys some of the most important changes in DSM-5, including structural/organizational changes, modifications of diagnostic criteria, and newly introduced categories. It analyzes why these changes led to such heated controversies, ...

it is essential to make urban spaces usable for a wide range of citizens, including aged people. this study was carried out in sari, the center of mazandaran province, northern iran in 2013 to prioritize five urban parks of the city using fuzzy-ahp method in terms of three pre-defined criteria, including safety, security, and environmental health. firstly, the criteria and alternatives were def...

conclusions it was shown that partial β-tubulin sequence, as a reliable genetic target, supported specific morphological criteria for identification of the penicillium species. like other assessments throughout the world, p. chrysogenum remains the most frequent environmental penicillium species in mazandaran and tehran provinces. results sequence analysis of bt2 and morphological criteria of 2...