Hand and gender differences in the organization of aiming in 5-year-old children.

The aim of the present study was to analyze the organization of aiming movements in right-handed children aged 5 years, depending on gender and hand used to perform the task. We first tested the hypothesis that aiming movements are predominantly organized in a feed-forward manner before the age of six. Using a direction pre-cueing protocol, we analyzed the effect of gender and hand used to perform the task on reaction time (RT), movement time (MT), spatial accuracy (SA) and acceleration profiles (APs) in children aged 5 years. Differences in RT between the uncued and pre-cued conditions suggest that the direction is actually specified prior to the execution of the movement at the age of five. However, the results also show significant hand and gender effects on MTs, spatial error and APs. Specifically, in girls, MT and kinematics profiles vary as a function of hand and target localization, whereas this is not the case in boys. In addition, SA is lower when aiming with the non-dominant hand in boys, but not in girls. These results suggest that multiple movement strategies are already available to the child at the age of five. Girls appear to be able to change movement strategy as a function of the constraints of the task, resulting in a stability of spatial accuracy (SA). On the contrary, the functional advantage of the right hand on MT and SA generally reported in right-handed males is not present in the boys at the age of five.     

Commercialization of BRCA1/2 testing: practitioner awareness and use of a new genetic test

It was our purpose to determine the characteristics of practitioners in the United States who were among the first to inquire about and use the BRCA1 and BRCA2 (BRCA1/2) genetic tests outside of a research protocol. Questionnaires were mailed to all practitioners who requested information on or ordered a BRCA1/2 test from the University of Pennsylvania (UPenn) Genetic Diagnostics Laboratory (GDL) between October 1, 1995 and January 1, 1997 (the first 15 months the test was available for clinical use). The response rate was 67% of practitioners; 54% (121/225) were genetic counselors, 39% (87/225) were physicians or lab directors. Most physicians were oncologists, pathologists, or obstetrician/gynecologists, but 20% practiced surgery or internal or general medicine. Fifty-six percent (125/225) had ordered a BRCA1/2 test for a patient; most of the rest had offered or were willing to offer testing. Of those who had offered testing, 70% had a patient decline BRCA1/2 testing when offered. Practitioners perceived that patients' fear of loss of confidentiality was a major reason for declining. Nearly 60% of practitioners reported that their patients had access to a genetic counselor, but 28% of physicians who ordered a BRCA1/2 test reported having no such access, despite the GDL's counseling requirement. The proportion of physicians reporting no access to genetic counselors for their patients increased from 22.4% in the first half of the study to 50% in the last half. Many practitioners have an interest in BRCA1/2 testing, despite policy statements that discourage its use outside of research protocols. Practitioner responses suggest that patient interest in testing seems to be tempered by knowledge of potential risks. An apparent increase in patient concern about confidentiality and inability to pay for testing could indicate growing barriers to testing. Although most practitioners reported having access to counseling facilities, perceived lack of such access among an increasing proportion of practitioners indicates that lab requirements for counseling are difficult to enforce and suggests that an increasing proportion of patients may not be getting access to counseling.     

Standardization for image characteristics in telemammography using genetic and nonlinear algorithms

As the soft copy reading and computer assisted diagnosis (CAD) in mammography become more and more important, the standardization of digital images becomes paramount. Telemammography and telemedicine requires the standardization for image characteristics, such as image resolution, bit-depth and intensity response. Soft copy reading and CAD in mammography are both dependent on the characteristics of the source of the digital data, either direct digital mammography or digitized screen-film mammography. An algorithm developed on images from one database may not perform well as on images from another database (with a different digitization). In this paper, we describe two methods based on a genetic algorithm and a nonlinear algorithm for standardization of digitized and digital mammography. The proposed standardization techniques are based on geometric and intensity transformations that are discovered using a set of calibration images. A set of transformation algorithm is used to search for the best standardization.