The complications of impaction bone grafting in revision hip replacement includes fracture of the femur and subsidence of the prosthesis. In this in vitro study we aimed to investigate whether the use of vibration, combined with a perforated tamp during the compaction of morsellised allograft would reduce peak loads and hoop strains in the femur as a surrogate marker of the risk of fracture and...

Issue: The moisture content of a fill material will affect its compaction characteristics and needs to be evaluated during quality control of the fill operation. When the fill is drier than its optimum moisture content, any moisture in the fill serves as a lubricant and helps the relative movement of the particles when densifying under vibratory compaction. When the fill is wetter than its opti...

In the cyanobacterium Synechococcus elongatus (PCC 7942) the kai genes A, B, and C and the sasA gene encode the functional protein core of the timing mechanism essential for circadian clock regulation of global gene expression. The Kai proteins comprise the central timing mechanism, and the sensor kinase SasA is a primary transducer of temporal information. We demonstrate that the circadian clo...

Tillage studies have shown that maximum, tillage-induced, aggregate breakdown occurs near the optimum water content on a Proctor compaction curve for the soil. Many soil databases do not contain Proctor data; therefore, prediction equations were developed to estimate the optimum water content, peak Proctor dry bulk density, and the Proctor compaction curve for a soil based on common intrinsic p...

Warm compaction takes advantage of temperature to favor densification during compaction. However, this technique requires powder mixes with specific physical characteristics to be adequately processed in the temperature range involved in warm pressing. The mix formulation, especially the lubricant/binder system, should provide good flowability and compressibility and lubrication of the die wall...

(Received: May 4, 2010; June 10, 2010) Abstract: Textile cardiovascular prostheses are woven or knitted structures made generally from biocompatible polyester fibres. After production, they have to undergo special treatments before packaging such as compaction. This treatment is necessary to reduce porosity especially for knitted structures, but it can modify poly(ethylene terephthalate) (PET) ...

Given a two dimensional, non-overlapping layout of convex and non-convex polygons, compaction can be thought of as simulating the motion of the polygons as a result of applied \forces." We apply compaction to improve the material utilization of an already tightly packed layout. Compaction can be modeled as a motion of the polygons that reduces the value of some functional on their positions. Op...

Abstract Study question Can endometrial compaction (EC) predict live birth/ongoing pregnancy rates (LBR/OPR) in assisted reproductive technology (ART) cycles? Summary answer Our meta-analysis shows that LBR/OPRs are similar cycles with or without EC. Analysis of studies euploid embryo transfers (ETs) also yield LBR/OPR. What is known already EC a novel concept, defined as change thickness (EMT)...

The Texas Department of Transportation (TxDOT) employs the impact hammer method of sample compaction for laboratory preparation of road base and subgrade materials for testing. Experience has shown that this method may not adequately represent the true field performance of the materials. This report describes results investigating how different lab compaction methods influence the laboratory ch...