Experimental studies on the tripping behavior of narrow T-stiffened flat plates subjected to hydrostatic pressure and underwater shock

An experimental investigation was conducted to determine the static and dynamic responses of a specific stiffened flat plate design. The air-backed rectangular flat plates of 6061-T6 aluminum with an externally machined longitudinal narrow-flanged T-stiffener and clamped boundary conditions were subjected to static loading by water hydropump pressure and shock loading from an eight pound TNT charge detonated underwater. The dynamic test plate was instrumented to measure transient strains and free field pressure. The static test plate was instrumented to measure transient strains, plate deflection, and pressure. Emphasis was placed upon forcing static and dynamic stiffener tripping, obtaining relevant strain and pressure data, and studying the associated plate-stiffener behavior

Should a Sentinel Node Biopsy Be Performed in Patients with High-Risk Breast Cancer?

A negative sentinel lymph node (SLN) biopsy spares many breast cancer patients the complications associated with lymph node irradiation or additional surgery. However, patients at high risk for nodal involvement based on clinical characteristics may remain at unacceptably high risk of axillary disease even after a negative SLN biopsy result. A Bayesian nomogram was designed to combine the probability of axillary disease prior to nodal biopsy with customized test characteristics for an SLN biopsy and provides the probability of axillary disease despite a negative SLN biopsy. Users may individualize the sensitivity of an SLN biopsy based on factors known to modify the sensitivity of the procedure. This tool may be useful in identifying patients who should have expanded upfront exploration of the axilla or comprehensive axillary irradiation

Metal-Ligand Cooperation at Phosphine-Based Acceptor Pincer Ligands

Acceptor ligands, which predominantly withdraw electron density from a transition metal center, often engage in weak metal-ligand interactions. These can be stabilized by flanking the acceptor moiety with strongly binding phosphines in a pincer motif, affording more robust complexes in which bond activation and/or bond-forming events can take place while preserving the integrity of the molecule as a whole. This contribution highlights recent developments in this area. Compounds incorporating a borane at the central position are discussed first, followed by compounds incorporating an electrophilic C = E (E = C, O, N) π-bond. In both cases, recent examples highlight the ability of these ligands to (1) respond to electronic changes at the metal by modifying their binding mode and (2) accept a nucleophilic fragment (e.g., hydride) from substrate molecules. Applications of acceptor pincer ligands as cooperative catalysts are discussed