Experimental investigations have shown that the enhancement in heat transfer coefficients for air flow in a channel roughened with low blockage (e/Dh < 0.1) angled ribs is on the average higher than that roughened with 90◦ ribs of the same geometry. Secondary flows generated by the angled ribs are believed to be responsible for these higher heat transfer coefficients. These secondary flows also...

Plates reinforced by ribs or joists are common elements in lightweight building structures, as well as in other engineering structures. However, these structures are not well suited for the common simplified prediction models such as Statistical Energy Analysis (SEA) or the European calculation standard EN 12354. There are several reasons for this: One is that the overall vibration field is not...

Designing structures that have minimal or zero coefficients of thermal expansion (CTE) are useful in many engineering applications. Zero thermal expansion is achievable with the design of porous materials. The behavior is primarily stretch-dominated, resulting in favorable stiffness. Two and three-dimensional lattices are designed using ribs consisting of straight tubes containing two nested sh...

Adamantinoma is a rare, low-grade, malignant bone tumour. We report on a 46-year-old woman who had early multiple recurrences of adamantinoma of the right tibia and late metastasis to the lung and ribs 13 years after the first surgical treatment. She underwent multiple complete tumour excisions and eventually below-knee amputation and removal of the left lung and sixth to eighth ribs.

Peniocereus striatus (Cactaceae) and Euphorbia cryptospinosa (Euphorbiaceae) both produce slender pencil-like stems with stomata restricted to series of furrows separated by bark-covered ribs. In each species, as the stems dehydrate, the ribs come together to close off the furrows. The unusual structure of these stems in two unrelated succulent genera is a remarkable example of evolutionary con...

A design methodology for collapsible rib-tensioned surface (CRTS) reflectors is presented. Offset configurations are explicitly addressed. For a reflector with aperture of 10 m diameter and focal length of 7.8 m, a root-mean-square surface accuracy of about 2 mm is achievable; this result scales linearly with the diameter. The design of a 1.5 m diameter prototype is presented, and the accuracy ...

BACKGROUND Congenital rib abnormalities are found in approximately 2% of the general population. Usually, they occur in isolation, when they are rarely symptomatic, but they can also associate with other malformations. MATERIALS AND METHODS We reviewed imaging examinations performed over a period of two years (2014-2015), enabling us to identify isolated rib abnormalities in six adult patient...

Two cases of bizarre skeletal anomalies associated with intestinal malformation are presented. One patient had ileal atresia and Hirschsprung's disease, and the other anorectal malformation. Abnormalities in the number and morphology of ribs and vertebrae were present. Esophageal atresia often is associated with skeletal abnormalities, including supernumerary ribs, but these usually are not sev...