Surface wrinkling of mucosae is crucial for the biological functions of many living tissues. In this paper, we investigate the instability of a cylindrical tube consisting of a mucosal layer and a submucosal layer. Our attention is focused on the effects of internal pressure and surface tension on the critical condition and mode number of surface wrinkling induced by tissue growth. It is found ...

OBJECTIVE A study was established to objectively assess the effects of low-intensity electromagnetic and electric stimulation plus negative pressure on mature scars. BACKGROUND Radiofrequency plus negative pressure therapy demonstrated a favorable reorganization and regeneration of the collagen and elastic fibers and was proposed for the treatment of cellulitis and skin stretch marks. METHO...

Seed-coat wrinkling in soybean is often observed when seeds are produced in adverse environmental conditions and it has been associated with low germinability. Manually rating seeds is time consuming, error prone and fatiguing – leading to even more errors. In this paper, an automated approach for the rating of seed-coat wrinkling using computer vision and machine learning algorithms is present...

A mesoscopic analytical model of wrinkling of Plain-Woven Composite Preforms (PWCPs) under the bias extension test is presented, based on a new instability analysis. The analysis is aimed to facilitate a better understanding of the nature of wrinkle formation in woven fabrics caused by large in-plane shear, while it accounts for the effect of fabric and process parameters on the onset of wrinkl...

Wrinkling modes are determined for a two-layer system comprised of a neo-Hookean film bonded to an infinitely deep neo-Hookean substrate with the entire bilayer undergoing compression. The full range of the film/substrate modulus ratio is considered from the limit of a traction-free homogeneous substrate to very stiff films on compliant substrates. The role of substrate prestretch is considered...

The transverse compression and shear collapse mechanisms of a second order, hierarchical corrugated truss structure have been analyzed. The two competing collapse modes of a first order corrugated truss are elastic buckling or plastic yielding of the truss members. In second order trusses, elastic buckling and yielding of the larger and smaller struts, shear buckling of the larger struts, and w...

Paper materials have a long history of use in packaging products, although traditional paper-based packaging is limited in its shape and design. In order to enable more advanced paper-based packaging, various 3-D forming processes for paper materials have been studied. Since 3-D forming processes typically include the application of moisture and/or temperature, the effects of moisture and tempe...

This paper presents a study on stretch-induced wrinkling of thin polyethylene sheets when subjected to uniaxial stretch with two clamped ends. Three-dimensional digital image correlation was used to measure the wrinkling deformation. It was observed that the wrinkle amplitude increased as the nominal strain increased up to around 10%, but then decreased at larger strain levels. This behavior is...

A key outstanding issue with turbulent premixed flames lies in modeling the burning rate which may be related to the flame surface density if the laminar flamelet assumption applies. Although it is generally accepted that, in the flamelet regimes, higher turbulence levels increases flame wrinkling and hence its surface density, recent imaging experiments are not consistent making this a controv...