Is the simple webbed penis a contraindication to circumcision?

Background Surgical correction of the webbed penis is challenging. We presented the safety and feasibility of webbed penis correction for neonates under local anesthesia using a simple principle of leaving equal cylindrical shaft skin. Methods This retrospective study included 530 patients who presented for circumcision to three pediatric surgery centers between May 2017 and January 2020. We included male patients aged less than four weeks old who had circumcision with a minimum of 6 months follow-up. We compared patients with normal penile anatomy (n = 451, Group 1) to a simple webbed penis (n = 79, Group 2). Results There were no differences in age and weight between groups. The procedure time was significantly longer in Group 2 (8.05 ± 3.11 vs. 7.48 ± 2.07 min; P = 0.04). There were no differences in bleeding (P = 0.38), redundant foreskin (P > 0.99), need for corrective surgery (P = 0.38), and re-suturing (P = 0.28) between groups. The procedure success was significantly higher in Group 1 (449 (99.56%) vs. 70 (88.6%); P < 0.001). Parents' satisfaction was measured at two weeks with no difference between both groups. Conclusion Simple penoscrotal web is not a contraindication for neonatal circumcision. Circumcision of the penoscrotal web had good esthetic results with comparable outcomes to those with a normal penis without a web.

Effect of Axial Deformation Caused by Torsion on a Solid Steel Cylinder

Equations describing the classical theory of applied torsion and axial rotation on a solid cylindrical shaft have been modified by Shirali and Hossain (2019) to derive new theorems, which can take into consideration axial deformation of members. The modified theorems use various empirical parameters to introduce the combined effect of axial force, axial displacement and axial rotation, which is neglected in classical theorems of torsion. Multiple finite element analysis models for solid steel cylindrical members, fixed at one end and subjected to torsion at its free end, were developed to study the effects of torsional loading. The effect of axial deformation/stress developed in the cylinder is analyzed and compared with values predicted by classical and proposed modified theorems (equations). It is shown that the cylinder can shorten or elongate when subjected to torsion. The proposed theorems/equations, based on axial deformation subjected to torsion, provide more accurate predictions of shear stress and axial rotation (angle of twist).

Effect of Axial Deformation Caused by Torsion on a Solid Steel Cylinder

Equations describing the classical theory of applied torsion and axial rotation on a solid cylindrical shaft have been modified by Shirali and Hossain (2019) to derive new theorems, which can take into consideration axial deformation of members. The modified theorems use various empirical parameters to introduce the combined effect of axial force, axial displacement and axial rotation, which is neglected in classical theorems of torsion. Multiple finite element analysis models for solid steel cylindrical members, fixed at one end and subjected to torsion at its free end, were developed to study the effects of torsional loading. The effect of axial deformation/stress developed in the cylinder is analyzed and compared with values predicted by classical and proposed modified theorems (equations). It is shown that the cylinder can shorten or elongate when subjected to torsion. The proposed theorems/equations, based on axial deformation subjected to torsion, provide more accurate predictions of shear stress and axial rotation (angle of twist).

The youngest occurrence of embolomeres (Tetrapoda: Anthracosauria) from the Sunjiagou Formation (Lopingian, Permian) of North China

Embolomeri were semiaquatic predators prevalent in the Carboniferous, with only two species from the early Permian (Cisuralian). A new embolomere, Seroherpeton yangquanensis gen. et sp. nov. (Zoobank Registration number: urn:lsid:zoobank.org:act:790BEB94-C2CC-4EA4-BE96-2A1BC4AED748, registration: 23 November 2020), is named based on a partial right upper jaw and palate from the Sunjiagou Formation of Yangquan, Shanxi, China, and is late Wuchiapingian (late Permian) in age. It is the youngest embolomere known to date and the only embolomere reported from North China Block. Its phylogenetic position within Embolomeri is confirmed by the strongly developed descending flange on the quadrate ramus of the pterygoid. The new taxon is unique among embolomeres by features like a partial coverage of a denticle shagreens on the pterygoid; presence of a cylindrical shaft on the pterygoid, and two pairs of very large ectopterygoid tusks. Phylogenetic analysis shows Seroherpeton as being the sister group of a clade consisting of Proterogyrinus, Archeria, and Pholiderpeton. We hypothesize that the dispersal and decline of the embolomeres from Carboniferous to late Permian (Lopingian) is related to the climate changes, especially aridification, of the paleotropical regions.

Cylindrical Developable Mechanisms for Minimally Invasive Surgical Instruments

Developable mechanisms conform to and emerge from developable, or specially curved, surfaces. The cylindrical developable mechanism can have applications in many industries due to the popularity of cylindrical or tube-based devices. Laparoscopic surgical devices in particular are widely composed of instruments attached at the proximal end of a cylindrical shaft. In this paper, properties of cylindrical developable mechanisms are discussed, including their behaviors, characteristics, and potential functions. One method for designing cylindrical developable mechanisms is discussed. Two example developable surgical devices that exemplify these behaviors, characteristics, and functions, along with the kinematic mechanisms comprising them, are discussed in detail.

Delamination of a Thin Film Driven by a Flat Cylindrical Shaft

An analytical model is derived for the delamination of a thin film from a rigid substrate by a cylindrical shaft with a flat end and finite radius. We show that, within certain limitations, a point-load model can be applied to the system, to give simple relations between the film-substrate energy of adhesion and the measured variables of applied shaft force, blister height, and blister radius. The results are applicable to systems where a finite size cylindrical shaft or disk generates delamination of the film from the substrate.