An atomic force field for simulating copper clusters and nanoparticles is developed. More than 2000 cluster configurations of varying size and shape are used to constrain the parametrization of the copper force field. Binding energies for these training clusters were computed using density functional theory. Extensive testing shows that the copper force field is fast and reliable for near-equil...

The viscosity of liquids under nanoconfinement remains controversial. Reports range from spontaneous solidification to no change in the viscosity at all. Here, we present thorough measurements with a small-amplitude linear atomic force microscopy technique and careful consideration of the confinement geometry, to show that in a weakly interacting liquid, average viscosity remains bulk like, exc...

INTRODUCTION: Shoulder motion following rotator cuff repair is unavoidable and may results in changes in tension on the repair and changes in compression forces at the rotator cuff footprint. We set out to determine how tension within the rotator cuff tendons and motion of the shoulder affect the footprint compression forces of a rotator cuff repair using multiple repair techniques. Ultimately,...

Whether blood flow during cardiopulmonary resuscitation (CPR) results from intrathoracic pressure fluctuations or direct cardiac compression remains controversial. From modeling considerations, blood flow due to intrathoracic pressure fluctuations should be insensitive to compression rate over a wide range, but dependent on the applied force and compression duration. If direct compression of th...

AIMS We investigated a new lead extraction tool (Compression Coil; One-Tie, Cook Medical) in an experimental traction force study. METHODS AND RESULTS On 13 pacemaker leads (Setrox JS53, Biotronik) traction force testing was performed under different configurations. The leads were assigned to three groups: (i) traction force testing without central locking stylet support (n = 5), (ii) tractio...

OBJECTIVE This study was conducted to evaluate stent compression in iliac vein compression syndrome (IVCS) and to identify its association with stent patency. MATERIALS AND METHODS Between May 2005 and June 2014, after stent placement for the treatment of IVCS with acute ilio-femoral deep vein thrombosis, follow-up CT venography was performed in 48 patients (35 women, 13 men; age range 23-87 ...

Enzymatic treatments were applied to rat motion segments to establish structure-function relationships and determine mechanical parameters most sensitive to simulated remodeling and degeneration. Rat caudal and lumbar disc biomechanical behaviors were evaluated to improve knowledge of their similarities and differences due to their frequent use during in vivo models. Caudal motion segments were...

crops and agricultural products are subject to natural loading during growth. different mechanical forces are also exerted on them during harvest. one product, sugar cane, experiences large shear forces are during harvest. an examination of the crop properties and machine parameters of sugar cane are necessary to develop appropriate cutting tools and the optimization and design of harvesting ma...

BACKGROUND The ability to dynamically control fingertip force vector magnitude and direction is critical for dexterous manipulation. We quantified the dynamic control of fingertip forces to examine how dexterous manipulation declines with age. METHODS The strength-dexterity (SD) test measures fingertip forces during compression of a slender spring prone to instability and buckling. The greate...

The predictability of multivariate calibration models, calculated with offline near-infrared spectroscopy (NIRS), assessing impact of magnesium stearate (MgSt) fraction, blending time, and compression force on the tablet breaking force (TBF) of SPRESS® B820 was statistically compared. Tablets of lubricated SPRESS® B820 were prepared by varying lubrication and compression conditions using 24 ful...