The Burton-Cabrera-Frank (BCF) theory of crystal growth has been successful in describing a wide range of phenomena in surface physics. Typical crystal surfaces are slightly mis-oriented with respect to a facet plane; thus, the BCF theory views such systems as composed of staircaselike structures of steps separating terraces. A continuous density of adsorbed atoms (adatoms) diffuses on the terr...

BACKGROUND To determine the influence of lifting speed and type on peak and cumulative back compressive force (BCF) and shoulder moment (SM) loads during symmetric lifting. Another aim of the study was to compare static and dynamic lifting models. METHODS Ten male participants performed a floor-to-shoulder, floor-to-waist, and waist-to-shoulder lift at three different speeds [slow (0.34 m/s),...

New laws resulting from enactment of the United Nations Stockholm Convention in May 2004 together with the new REACH legislation, have led to significant new activity in the assessment of Persistent, Bioaccumulative, Toxic substances (PBT). Bioconcentration is the process of accumulation of chemicals by organisms through non-dietary routes. The tendency of a substance to bioconcentrate in aquat...

The Burton-Cabrera-Frank (BCF) model of step flow has been recognized as a valuable tool for describing nanoscale surface evolution of crystals. In this work, we formally derive the BCF theory from an atomistic, kinetic Monte Carlo model of a crystal surface in 1+1 dimensions with a single step, in the absence of external material deposition. In order to reconcile the discrete nature of the kMC...

The enactment of new chemical regulations has generated a large need for the measurement of the fish bioconcentration factor (BCF). Past experience shows that the BCF determination lacks precision, requires large numbers of fish, and is costly. A new protocol was tested that shortens the experiment from up to 12 weeks for existing protocols to 2 weeks and reduces the number of fish by a factor ...

PURPOSE To investigate the association between external beam radiotherapy (EBRT) dose and biochemical failure (BcF) of prostate cancer in patients who received salvage prostate bed EBRT for a rising prostate-specific antigen (PSA) level after radical prostatectomy. METHODS AND MATERIALS We evaluated patients with a rising PSA level after prostatectomy who received salvage EBRT between July 19...

The relationships between the bioconcentration factor (BCF) of chemicals in fish and their size, as characterized by molecular weight (MW), effective cross sectional diameter (Deff), and maximum diameter (Dmax) have been investigated using an experimental data set of 737 new and 441 existing chemicals monitored by the Japanese Chemical Substances Control Law (CSCL). Substances with BCF > or = 5...

A typical undergraduate biology curriculum covers a very large number of concepts and details. We describe the development of a Biology Concept Framework (BCF) as a possible way to organize this material to enhance teaching and learning. Our BCF is hierarchical, places details in context, nests related concepts, and articulates concepts that are inherently obvious to experts but often difficult...

This study aimed to determine the effects of Bauhinia championii flavone (BCF) on hypoxia-reoxygenation (H/R) induced apoptosis in H9c2 cardiomyocytes and to explore potential mechanisms. The H/R model in H9c2 cardiomyocytes was established by 6 h of hypoxia and 12 h of reoxygenation. Cell viability was detected by CCK-8 assay. Apoptotic rate was measured by Annexin V/PI staining. Levels of mit...

A bioconcentration factor (BCF) estimation model for a wide range of nonionic organic compounds was developed on the basis of molecular connectivity indices and polarity correction factors. The nonlinear topological modeling using polarity correction factors resulted in the best BCF estimation quality for all of the 239 compounds studied, with a mean absolute estimation error of 0.478 log units...