Drought stress is one of the most important abiotic stresses influencing performance of crop plants. Therefore, the identification or development of tolerant genotypes is of high importance for incorporating in cotton production. In this study to evaluate the effect of drought stress on some cotton traits, 5 improved cotton varieties were studied in a split plot design with three replications i...

objective: experiencing ‎pleasant events during daily life ‎has a significant positive role in ‎the personal mental health and ‎acts as a keystone for “behavioral ‎activation” (ba) interventions. ‎there are serious differences in ‎the pleasant event schedules in ‎different cultures and countries. ‎we aimed to develop a persian ‎checklist of pleasant events ‎‎(pcpe) to provide and validate a ‎cu...

In this research, the surface stress effect on the nonlocal vibration of piezoelectric square plate reinforced by single walled carbon nanotubes (SWCNTs) based on classical plate theory (CPT) and first order shear deformation theory (FSDT) is presented. The elastic properties of piezoelectric nanocomposite plate are estimated by Eshelby-Mori-Tanaka and the extended mixture rule approaches. The ...

A finite element model was developed to simulate the vibratory stress relief after welding. Both resonant and nonresonant vibrations can relieve residual stresses in welded structures by creating plastic deformation around the weld area. For the non-resonant vibration, the stress reduction strongly depends on the vibration amplitude. For the resonant vibration, the vibration frequency is the ke...

We derive a two parameter multi-exponential model to describe the frequency spectrum of Barkhausen noise in bulk steel under high excitation rates and applied tensile stress. We show how the amplitude and shape of the frequency spectrum depend on two directly measurable quantities, Barkhausen voltage and effective magnetic permeability, respectively, and how these change with stress. By incorpo...

The hysteresis or internal friction in the deformation of crystalline solids stressed cyclically is studied from the viewpoint of collective dislocation dynamics. Stress-controlled simulations of a dislocation dynamics model at various loading frequencies and amplitudes are performed to study the stress-strain rate hysteresis. The hysteresis loop areas exhibit a maximum at a characteristic freq...

background and purpose: job stress is an important psychological factor. musculoskeletal disorders are among the most common causes of disability in industrialized and developing countries. therefore, this study aimed to assess job stress and its relationship with the prevalence of musculoskeletal disorders in office workers of zahedan university of medical sciences, iran. materials and methods...

periodontal ligament is a thin layer of soft tissue that connects root of a tooth to the surrounding alveolar bone. these ligaments play an important role in initiating tooth movement when loads are applied to teeth with orthodontic appliances. the majority of such soft tissues exhibit as viscoelastic bodies or have a time-dependent behavior. due to the viscoelastic behavior of the periodontal ...