LES of physiological blood flow in diseased basilar artery: semi-patient specific model

Large Eddy Simulation (LES) is applied to study physiological pulsatile spiral and non-spiral blood flow through a model of an irregular stenosis with an adjacent post-stenotic fusiform irregular aneurysm in basilar artery. The stenosis and the aneurysm are of 75% area reduction and 126% area enlargement, respectively, at their centres [1]. Numerical results of various important physical quantities are presented to particularly investigate the transition-to-turbulence nature of the pulsatile flow with their relevant clinical implications

Pulsatile spiral blood flow through arterial stenosis

Pulsatile spiral blood flow in a modelled three-dimensional arterial stenosis, with a 75% cross-sectional area reduction, is investigated by using numerical fluid dynamics. Two-equation k-ω model is used for the simulation of the transitional flow with Reynolds numbers 500 and 1000. It is found that the spiral component increases the static pressure in the vessel during the deceleration phase of the flow pulse. In addition, the spiral component reduces the turbulence intensity and wall shear stress found in the post-stenosis region of the vessel in the early stages of the flow pulse. Hence, the findings agree with the results of Stonebridge et al. (2004). In addition, the results of the effects of a spiral component on time-varying flow are presented and discussed along with the relevant pathological issues

A new test procedure to validate tensile dynamic mechanical properties of sheet metals and alloys in automotive crash applications

A thin walled open channel beam subjected to a 3-point bend and constant velocity boundary condition is investigated to establish its potential to validate material performance for automotive crash applications. Specifically quantitative validation of material data determined from high speed tensile testing and qualitative validation of material resistance to fracture in crash components. Open channel beams are fabricated from structural grade sheet steel and aluminium alloy and tested at quasi-static and higher speeds up to 10 m/s and in all cases, deformation develops a plastic hinge. This paper describes development of the validation test procedure, specifically design of specimen, system of measurement and boundary conditions using numerical and experimental techniques. The new test procedure will increase confidence in materials modelling and reduce the risk to introduce new advanced high strength materials into automotive crash structures

Modelling self-piercing riveted joint failures in automotive crash structures

This paper describes a new model and method to predict Self-Piercing Riveted (SPR) joint interlock failures in aluminium sheet at crash speeds using explicit finite element simulation. SPR interlock failure is dependent on rivet direction, which is included in the model. A mesh independent approach is adopted for connection model which is capable of industrial application at the full vehicle crash analysis level. The paper provides an overview of the approach to validate connection model; typically by developing detailed physics based models of various joint configurations supported with high speed experimental data, through to model capable of industrial application. The framework to validate connection model for use in crash simulation tools is expected to have broader applicatio

Validating dynamic tensile mechanical properties of sheet steels for automotive crash applications

A thin-wall open channel beam, fabricated from high strength Dual Phase sheet steel, subjected to 3-point bending and constant velocity boundary condition, is investigated to validate material performance for automotive crash applications. Specifically quantitative validation of material tensile data determined from high speed tests and component models, and qualitative validation of materials resistance to fracture. The open channel beam is subjected to quasi-static and increasing loading speed and in all cases, large displacement in which deformation involves formation of a plastic hinge. This paper describes development of test procedure, notably beam specimen design, measurement system and boundary conditions, using both experimental and numerical techniques. The new test procedure, as a compliment to crush testing, will increase confidence in the modeling and application of new advanced higher strength materials in automotive crash structure

Psychological Warfare

Gentlemen, psychological warfare is an elaborate and curently popular label for a wide variety of subjects. I cannot present specifically naval doctrine to you, nor is it my province to delineate those distinctions which—in sound naval theory­—should prevail between psychological warfare, political warfare, special operations, economic warfare, sabotage activities, guer­rilla warfare, and a variety of other related subjects

Design, synthesis, conformational analysis and nucleic acid hybridisation properties of thymidyl pyrrolidine-amide oligonucleotide mimics (POM)

Pyrrolidine-amide oligonucleotide mimics (POM) 1 were designed to be stereochemically and conformationally similar to natural nucleic acids, but with an oppositely charged, cationic backbone. Molecular modelling reveals that the lowest energy conformation of a thymidyl-POM monomer is similar to the conformation adopted by ribonucleosides. An e cient solution phase synthesis of the thymidyl POM oligomers has been developed, using both N-alkylation and acylation coupling strategies. 1H NMR spectroscopy con rmed that the highly water soluble thymidyl-dimer, T2-POM, preferentially adopts both a con guration about the pyrrolidine N-atom and an overall conformation in D2O that are very similar to a typical C3 -endo nucleotide in RNA. In addition the nucleic acid hybridisation properties of a thymidyl-pentamer, T5-POM, with an N-terminal phthalimide group were evaluated using both UV spectroscopy and surface plasmon resonance (SPR). It was found that T5-POM exhibits very high a nity for complementary ssDNA and RNA, similar to that of a T5-PNA oligomer. SPR experiments also showed that T5-POM binds with high sequence delity to ssDNA under near physiological conditions. In addition, it was found possible to attenuate the binding a nity of T5-POM to ssDNA and RNA by varying both the ionic strength and pH. However, the most striking feature exhibited by T5-POM is an unprecedented kinetic binding selectivity for ssRNA over DNA

A computational study on spiral blood flow in stenosed arteries with and without an upstream curved section

Spiral and non-spiral blood flows through three-dimensional models of 75% axisymmetric arterial stenosis are investigated by using two-equation standard k  -ω transitional model and Large Eddy Simulation (LES). The arterial stenosis models chosen are straight stenosed tubes without and with upstream curved segments of various angles of curvature. The Reynolds numbers investigated are 500,1000,1500 and 2000. Spiral effect is introduced by taking one-sixth of the bulk velocity as a tangential velocity at the inlet, and the inlet turbulence intensity was introduced for matching experimental results. LES results with a right amount of inlet turbulence intensity matches experimental results better than the k  -ω results. The results show that the spiral flow affects the turbulence kinetic energy in the post stenosis region. Other important results such as the wall pressure and shear stress remain almost unchanged by the spiral velocity. But the presence of the upstream curved segment in artery moderately affects the results of the maximum pressure drop and wall shear stress

Interview of Frank McKee, M.A. English, M.A. Ed. Admin.

Frank McKee was born in Philadelphia, PA in 1948. His father was a World World II veteran and battery worker, his mother a key-punch operator and homemaker. Growing up in Olney, only fifteen minutes from La Salle’s campus, Frank attended Catholic schools his entire childhood. In 1967 he enrolled at La Salle as an English major but always knew that education was his true passion. Frank lived off campus and worked throughout his undergraduate experience, however, La Salle remained a social hub for him. In 1971, Frank graduated and shortly thereafter was hired to teach at North Catholic High School. Concurrently, Frank began a six-year active duty contract with the Army as a Electronic Warfare Operator Analyst. Working covertly stateside, Frank was able to compartmentalize teaching and spying while also completing two Master’s degrees at Villanova. He received a Master’s in both English and Educational Administration with a Principal’s certification. By age 27, Frank’s contract with the military expired in the same summer that he was hired to be English Department Chair for Lower Moreland County schools. Frank worked in Lower Moreland for thirty-five years under a number of different titles. Frank’s accomplishments include being Principal in both middle and high school, coaching track-and-field and creating an American Studies program for the district. Frank was encourage to return to La Salle by Dr. Francis Ryan as an adjunct professor in 1988 for the night program. Frank stayed, teaching one or two nights a week, for four years until his youngest daughter was born in 1992. He admitted during our interview that he could have provided more support to the students and that disappointment was a factor in his returning a second time. Again, Dr. Ryan reached out to Frank, this time to teach in the American Studies program in 2012. In the same year, Frank retired from Lower Moreland County which allowed him to focus all his energy towards La Salle. On June 1, 2017, when Dr. Ryan vacates the American Studies Department Chair, Frank will be promoted to the same position. The interview focuses mainly on Frank’s career as an educator and his reflections and ambitions towards La Salle University