Genetic testing and its implications: human genetics researchers grapple with ethical issues

To better understand ethical issues involved in the field of human genetics and promote debate within the scientific community, the author surveyed scientists who engage in human genetics research about the pros, cons, and ethical implications of genetic testing. This study contributes systematic data on attitudes of scientific experts. The survey finds respondents are highly supportive of voluntary testing and the right to know one's genetic heritage. The majority consider in utero testing and consequent pregnancy termination acceptable for cases involving likelihood of serious disease but disapprove for genetic reasons they consider arbitrary, leaving a gray area of distinguishing between treatment of disorders and enhancement still to be resolved. While safeguarding patient confidentiality versus protecting at-risk third parties (kin, reproductive partners) presents a dilemma, preserving privacy from misuse by institutional third parties (employers, insurers) garners strong consensus for legislation against discrimination. Finally, a call is made for greater genetic literacy.     

Effect of stroke rate on the distribution of net mechanical power in rowing

The aim of this study was to assess the effect of manipulating stroke rate on the distribution of mechanical power in rowing. Two causes of inefficient mechanical energy expenditure were identified in rowing. The ratio between power not lost at the blades and generated mechanical power (P(rower)) and the ratio between power not lost to velocity fluctuations and P(rower) were used to quantify efficiency (e(propelling) and e(velocity) respectively). Subsequently, the fraction of P(rower) that contributes to the average velocity (chi(boat)) was calculated (e(net)). For nine participants, stroke rate was manipulated between 20 and 36 strokes per minute to examine the effect on the power flow. The data were analysed using a repeated-measures analysis of variance. Results indicated that at higher stroke rates, P(rower), chi(boat), e(propelling), and e(net) increase, whereas e(velocity) decreases (P < 0.0001). The decrease in e(velocity) can be explained by a larger impulse exchange between rower and boat. The increase in e(propelling) can be explained because the work at the blades decreases, which in turn can be explained by a change in blade kinematics. The increase in e(net) results because the increase in e(propelling) is higher than the decrease in e(velocity). Our results show that the power equation is an adequate conceptual model with which to analyse rowing performance.     

Design and evaluation of awareness mechanisms in CiteSeer

Awareness has been extensively studied in human computer interaction (HCI) and computer supported cooperative work (CSCW). The success of many collaborative systems hinges on effectively supporting awareness of different collaborators, their actions, and the process of creating shared work products. As digital libraries are increasingly becoming more than just repositories for information search and retrieval – essentially fostering collaboration among its community of users – awareness remains an unexplored research area in this domain. We are investigating awareness mechanisms in CiteSeer, a scholarly digital library for the computer and information science domain. CiteSeer users can be notified of new publication events (e.g., publication of a paper that cites one of their papers) using feeds as notification systems. We present three cumulative user studies – requirements elicitation, prototype evaluation, and naturalistic study – in the context of supporting CiteSeer feeds. Our results indicate that users prefer feeds that place target items in query-relevant contexts, and that preferred context varies with type of publication event. We found that users integrated feeds as part of their broader, everyday activities and used them as planning tools to collaborate with others.     

Counting cells with a low-cost integrated microfluidics-waveguide sensor

The capability to count cells from biofluids at low cost has important diagnostic implications in resource-poor settings. Many approaches have been developed to address this important need, and while most envision a low per-test cost, the detector instrument can be quite expensive. In this report, we present a novel device that enables low-cost and rapid counting of cells from a drop of blood. We demonstrate a shallow, buried, planar waveguide fabricated by ion exchange in glass that underlies a microfluidic structure for capturing cells. Laser light transmitted through the waveguide was attenuated by the number of metal nanoparticles tagged to the cells because of the interaction of the metal particles with the evanescent field of the waveguide. Calibration of the sensor using bead-tagged lymphocytes captured from human blood showed that the sensor could semi-quantitatively count as few as 100 cells/μL of blood. This technology enables the enumeration of specifically captured cells, allowing for a point-of-care, hand-held device for fast and affordable cell counting in screening, remote, or resource-poor settings.