Development of a scale for data quality assessment in automated library systems

A credible scale based on the opinions of system users was developed to evaluate and assess data quality in automated library systems (ALS). Development and testing were carried out in two stages. In the first stage, 77 dimensions for data quality which had been previously identified through a systematic literature review were used to develop scale items. The first draft of the scale was then distributed among a target population of ALS experts to solicit their opinions on the scale and the items. In the second stage, a revised version of the scale was distributed among the main study population, which included end users of the target systems. This stage used factor analysis to determine the final draft of the scale, which consists of 4 factors and 62 items. The 4 factors were named after the qualities of their associated items: Data Content Quality, Data Organizational Quality, Data Presentation Quality, and Data Usage Quality. This scale can help system managers identify and resolve potential problems in the systems they manage and can also aid in evaluating the quality of data sources based on the opinions of end users.     

Efficient capture of circulating tumor cells with a novel immunocytochemical microfluidic device

Ability to perform cytogenetic interrogations on circulating tumor cells (CTCs) from the blood of cancer patients is vital for progressing toward targeted, individualized treatments. CTCs are rare compared to normal (bystander) blood cells, found in ratios as low as 1:10⁹. The most successful isolation techniques have been immunocytochemical technologies that label CTCs for separation based on unique surface antigens that distinguish them from normal bystander cells. The method discussed here utilizes biotin-tagged antibodies that bind selectively to CTCs. The antibodies are introduced into a suspension of blood cells intending that only CTCs will display surface biotin molecules. Next, the cell suspension is passed through a microfluidic channel that contains about 9000 transverse, streptavidin coated posts. A CTC making contact with a post has the opportunity to engage in a biotin-streptavidin reaction that immobilizes the cell. Bystander blood cells remain in suspension and pass through the channel. The goal of the present study is to establish the technical performance of these channels as a function of antigen density and operating conditions, especially flow rate. At 18 μL/min, over 70% of cells are captured at antigen densities greater than 30 000 sites/cell while 50% of cells are captured at antigen densities greater than 10 000. It is found that lower flow rates lead to decreasing cell capture probabilities, indicating that some streamlines develop which are never close enough to a post to allow cell-post contact. Future modeling and streamline studies using computational fluid dynamics software could aid in optimization of channel performance for capture of rare cells.     

Hyperactivity among Hong Kong Chinese children

Hyperactivity has been claimed to be predominantly an American phenomenon. The present study used Conners' Abbreviated Teacher Rating scale to rate 506 normal Chinese children in Hong Kong as well as 167 children independently diagnosed as hyperactive. Sex differences similar to American findings were noted, although the ratings for Chinese girls were much lower. Overall decrease in hyperactive symptoms towards adolescence was also found. The possible influence of cultural factors on incidence of hyperactivity is discussed.