2,109 research outputs found
An influence assessment method based on co-occurrence for topologically reduced big data sets
Health Insurance, Employment, and the Human Genome: Genetic Discrimination and Biobanks in the United States
Does genetic information warrant special legal protection, and if so how should it be protected? This essay examines the most recent (and indeed only) significant effort by the US government to prohibit genetic discrimination, the Genetic Information Nondiscrimination Act (GINA). We argue that the legislation is unlikely to have the positive impact sought by advocates of genetic privacy and proponents of biobanks. In part, GINA disappoints because it does too little. Hailed by its promoters as “the first civil rights act of the 21st century,” GINA’s reach is in fact quite modest and its grasp even more so. But GINA also fails by trying to do too much, tying the hands of insurers and employers in ways that may fail to serve the interests of individuals or society more generally. In short, if genetic discrimination is a problem that needs to be solved, GINA is not the solution. Instead, the Act creates a number of new and possibly intractable problems that may be more troublesome than what it originally set out to resolve
Rectified voltage induced by a microwave field in a confined two-dimensional electron gas with a mesoscopic static vortex
We investigate the effect of a microwave field on a confined two dimensional
electron gas which contains an insulating region comparable to the Fermi
wavelength. The insulating region causes the electron wave function to vanish
in that region. We describe the insulating region as a static vortex. The
vortex carries a flux which is determined by vanishing of the charge density of
the electronic fluid due to the insulating region. The sign of the vorticity
for a hole is opposite to the vorticity for adding additional electrons. The
vorticity gives rise to non-commuting kinetic momenta. The two dimensional
electron gas is described as fluid with a density which obeys the Fermi-Dirac
statistics. The presence of the confinement potential gives rise to vanishing
kinetic momenta in the vicinity of the classical turning points. As a result,
the Cartesian coordinate do not commute and gives rise to a Hall current which
in the presence of a modified Fermi-Surface caused by the microwave field
results in a rectified voltage. Using a Bosonized formulation of the two
dimensional gas in the presence of insulating regions allows us to compute the
rectified current. The proposed theory may explain the experimental results
recently reported by J. Zhang et al.Comment: 14 pages, 2 figure
Toward High-Precision Measures of Large-Scale Structure
I review some results of estimation of the power spectrum of density
fluctuations from galaxy redshift surveys and discuss advances that may be
possible with the Sloan Digital Sky Survey. I then examine the realities of
power spectrum estimation in the presence of Galactic extinction, photometric
errors, galaxy evolution, clustering evolution, and uncertainty about the
background cosmology.Comment: 24 pages, including 11 postscript figures. Uses crckapb.sty (included
in submission). To appear in ``Ringberg Workshop on Large-Scale Structure,''
ed D. Hamilton (Kluwer, Amsterdam), p. 39
Specific staining of human chromosomes in Chinese hamster x man hybrid cell lines demonstrates interphase chromosome territories
In spite of Carl Rabl's (1885) and Theodor Boveri's (1909) early hypothesis that chromosomes occupy discrete territories or domains within the interphase nucleus, evidence in favor pf this hypothesis has been limited and indirect so far in higher plants and animals. The alternative possibility that the chromatin fiber of single chromosomes might be extended throughout the major part of even the whole interphase nucleus has been considered for many years. In the latter case, chromosomes would only exist as discrete chromatin bodies during mitosis but not during interphase. Both possibilities are compatible with Boveri's well established paradigm of chromosome individuality. Here we show that an active human X chromosome contained as the only human chromosome in a Chinese hamster x man hybrid cell line can be visualized both in metaphse plates and in interphase nuclei after in situ hybridization with either 3H- or biotin-labeled human genomic DNA. We demonstrate that this chromosome is organized as a distinct chromatin body throughout interphase. In addition, evidence for the territorial organization of human chromosomes is also presented for another hybrid cell line containing several autosomes and the human X chromosome. These findings are discussed in the context of our present knowledge of the organization and topography of interphase chromosomes. General applications of a strategy aimed at specific staining of individual chromosomes in experimental and clinical cytogenetics are briefly considered
How do parents of children with juvenile idiopathic arthritis (JIA) perceive their therapies?
<p>Abstract</p> <p>Background</p> <p>Complementary and alternative medical (CAM) therapies are commonly used by pediatric patients with chronic medical conditions. Little is known about parents' perceptions of these therapies. This study describes the views of parents of patients with juvenile idiopathic arthritis (JIA) regarding conventional and CAM therapies.</p> <p>Methods</p> <p>Parents of children with JIA seen at a pediatric rheumatology clinic were surveyed between June 1 and July 31, 2007. Questionnaires asked about patients' use of over 75 therapies in the past 30 days, their perceived helpfulness (0 = not helpful; 3 = very helpful), perceived side effects (0 = none; 3 = severe), and whether each therapy would be recommended to other patients with JIA (Yes, No, Not sure).</p> <p>Results</p> <p>Questionnaires were returned by 52/76 (68%) parents; patients' average age was 10.9 years and 87% were Caucasian. Medications were used by 45 (88%) patients; heat (67%) and extra rest (54%) were also commonly used. CAM therapies were used by 48 (92%), e.g., massage (54%), vitamins and other supplements (54%), avoiding foods that worsened pain (35%) and stress management techniques (33%). Among the therapies rated by 3 or more parents, those that scored 2.5 or higher on helpfulness were: biologic medications, methotrexate, naproxen, wheelchairs, orthotics, heat, vitamins C and D, music, support groups and prayer. CAM therapies had 0 median side effects and parents would recommend many of them to other families.</p> <p>Conclusion</p> <p>JIA patients use diverse therapies. Parents report that many CAM therapies are helpful and would recommend them to other parents. These data can be used in counseling patients and guiding future research.</p
Identification of sex hormone-binding globulin in the human hypothalamus
Gonadal steroids are known to influence hypothalamic functions through both genomic and non-genomic pathways. Sex hormone-binding globulin ( SHBG) may act by a non-genomic mechanism independent of classical steroid receptors. Here we describe the immunocytochemical mapping of SHBG-containing neurons and nerve fibers in the human hypothalamus and infundibulum. Mass spectrometry and Western blot analysis were also used to characterize the biochemical characteristics of SHBG in the hypothalamus and cerebrospinal fluid (CSF) of humans. SHBG-immunoreactive neurons were observed in the supraoptic nucleus, the suprachiasmatic nucleus, the bed nucleus of the stria terminalis, paraventricular nucleus, arcuate nucleus, the perifornical region and the medial preoptic area in human brains. There were SHBG-immunoreactive axons in the median eminence and the infundibulum. A partial colocalization with oxytocin could be observed in the posterior pituitary lobe in consecutive semithin sections. We also found strong immunoreactivity for SHBG in epithelial cells of the choroid plexus and in a portion of the ependymal cells lining the third ventricle. Mass spectrometry showed that affinity-purified SHBG from the hypothalamus and choroid plexus is structurally similar to the SHBG identified in the CSF. The multiple localizations of SHBG suggest neurohypophyseal and neuroendocrine functions. The biochemical data suggest that CSF SHBG is of brain rather than blood origin. Copyright (c) 2005 S. Karger AG, Base
Skills training in minimally invasive surgery in Dutch obstetrics and gynecology residency curriculum
The complexity of acquiring minimally invasive surgical (MIS) skills, combined with smaller case volumes for residents have pushed the development of skills training facilities on simulators outside the operating room (OR). Medico-legal and financial constraints have stimulated this development even more. However, the implementation of simulator training into a residency curriculum is shown to be troublesome. MIS skills training is organized in a uniform and easily applicable way in the Dutch obstetrics and gynecology residency curriculum. Every resident is obliged to attend the same basic surgical skills course, named Cobra-alpha course, intentionally during postgraduate year (PGY) 1 or 2. Furthermore, surgical skills are trained, evaluated and expanded on simulators in teaching hospitals. Additional to the Cobra-alpha course, residents may attend advanced training courses and congresses focusing on laparoscopy and hysteroscopy. This organization guarantees a uniform introduction to MIS skills training for every resident. However, preconditions for continuous training and evaluation after this introduction have to be optimized
An exploration of parents’ preferences for foot care in juvenile idiopathic arthritis: a possible role for the discrete choice experiment
Background:
An increased awareness of patients’ and parents’ care preferences regarding foot care is desirable from a clinical perspective as such information may be utilised to optimise care delivery. The aim of this study was to examine parents’ preferences for, and valuations of foot care and foot-related outcomes in juvenile idiopathic arthritis (JIA).<p></p>
Methods:
A discrete choice experiment (DCE) incorporating willingness-to-pay (WTP) questions was conducted by surveying 42 parents of children with JIA who were enrolled in a randomised-controlled trial of multidisciplinary foot care at a single UK paediatric rheumatology outpatients department. Attributes explored were: levels of pain; mobility; ability to perform activities of daily living (ADL); waiting time; referral route; and footwear. The DCE was administered at trial baseline. DCE data were analysed using a multinomial-logit-regression model to estimate preferences and relative importance of attributes of foot care. A stated-preference WTP question was presented to estimate parents’ monetary valuation of health and service improvements.<p></p>
Results:
Every attribute in the DCE was statistically significant (p < 0.01) except that of cost (p = 0.118), suggesting that all attributes, except cost, have an impact on parents’ preferences for foot care for their child. The magnitudes of the coefficients indicate that the strength of preference for each attribute was (in descending order): improved ability to perform ADL, reductions in foot pain, improved mobility, improved ability to wear desired footwear, multidisciplinary foot care route, and reduced waiting time. Parents’ estimated mean annual WTP for a multidisciplinary foot care service was £1,119.05.<p></p>
Conclusions:
In terms of foot care service provision for children with JIA, parents appear to prefer improvements in health outcomes over non-health outcomes and service process attributes. Cost was relatively less important than other attributes suggesting that it does not appear to impact on parents’ preferences.<p></p>
Identifying patient preferences for communicating risk estimates: A descriptive pilot study
BACKGROUND: Patients increasingly seek more active involvement in health care decisions, but little is known about how to communicate complex risk information to patients. The objective of this study was to elicit patient preferences for the presentation and framing of complex risk information. METHOD: To accomplish this, eight focus group discussions and 15 one-on-one interviews were conducted, where women were presented with risk data in a variety of different graphical formats, metrics, and time horizons. Risk data were based on a hypothetical woman's risk for coronary heart disease, hip fracture, and breast cancer, with and without hormone replacement therapy. Participants' preferences were assessed using likert scales, ranking, and abstractions of focus group discussions. RESULTS: Forty peri- and postmenopausal women were recruited through hospital fliers (n = 25) and a community health fair (n = 15). Mean age was 51 years, 50% were non-Caucasian, and all had completed high school. Bar graphs were preferred by 83% of participants over line graphs, thermometer graphs, 100 representative faces, and survival curves. Lifetime risk estimates were preferred over 10 or 20-year horizons, and absolute risks were preferred over relative risks and number needed to treat. CONCLUSION: Although there are many different formats for presenting and framing risk information, simple bar charts depicting absolute lifetime risk were rated and ranked highest overall for patient preferences for format
- …