616 research outputs found

    Questions in a Research Setting

    Get PDF
    Because closed-ended (multiple-choice) questioning formats are often used in educational research, it is important to understand how presenting response options can affect the data obtained. In this study children and adults answered questions in an open-ended condition or one of two closed-ended conditions where options were either likely or unlikely. Participants who were presented with unlikely response options generated their own responses more often than participants who were presented with likely response options. On the other hand, children were more likely than adults to choose the presented response options regardless of how unlikely they were. These findings have important research implications; response options for closed-ended data collection devices must be selected carefully to reflect real-world possibilities.Étant donné que l'on emploie souvent des questionnaires sous forme de questions fermées (à choix multiples) dans la recherche en éducation, il est important de comprendre comment la présentation du choix de réponses peut influencer les données ainsi obtenues. Les enfants et les adultes qui ont participé à cette étude ont répondu soit à des questions ouvertes, soit à des questions fermées où les choix de réponses étaient probables ou improbables. Les participants à qui on avait présenté des choix de réponses improbables ont produit leurs propres réponses plus souvent que ceux à qui on avait présenté des choix de réponses probables. Par ailleurs, les enfants étaient plus portés que les adultes à choisir les réponses proposées, indépendamment de leur improbabilité. Ces résultats ont des implications importantes pour la recherche: dans la collecte de données, il est important de bien formuler les choix de réponses aux questions fermées pour qu'ils constituent des possibilités réalistes

    The nature of eye movements in Cerebral Palsy: A case study on the effects of posture on oculomotor control and visual function

    Get PDF
    A case study was performed on a child with cerebral palsy to evaluate the effects of providing postural support on visual performance, including oculomotor control, visual acuity, and reading comprehension. The hypothesis was that providing postural support for specific visual tasks would help the subject perform at a level of maximal efficiency for learning. We tested the subject with and without postural support, and measured the effects on visual acuity, oculomotor accuracy and reading comprehension. Oculomotor skills were measured by using a modified NSUCO Oculomotor Test and Visagraph II. The Visagraph II was also used to test reading comprehension. Postural support was provided in the form of a cervical collar. Results suggest that postural support does not improve visual acuity or oculomotor control. Instead, postural support seemed to impede those precise visual tasks by restraining the child\u27s head movement. We have found that in this case study, this subject had learned to use head movement for reading and precise visual tasks. Postural head support seemed to restrict the head movement, thereby restricting the child\u27s visual function

    New records for the liverwort and hornwort flora of Vietnam, 1

    Get PDF
    After the examination of the Cryptogam collection in the Herbarium of the University of Science, Vietnam National University Ho Chi Minh City (PHH), 25 species proved to be new to Vietnam, including one hornwort and 24 liverworts. Among them, four genera: Denotarisia Grolle, Gongylanthus Nees, Leiomitra Lindb. and Lepicolea Dumort. are new records for the country. Diagnostic characters and illustrations are given for some taxa, as well as locality notes and habitat descriptions are provided for each collecting area

    Identifying rheumatoid arthritis susceptibility genes using high-dimensional methods

    Get PDF
    Although several genes (including a strong effect in the human leukocyte antigen (HLA) region) and some environmental factors have been implicated to cause susceptibility to rheumatoid arthritis (RA), the etiology of the disease is not completely understood. The ability to screen the entire genome for association to complex diseases has great potential for identifying gene effects. However, the efficiency of gene detection in this situation may be improved by methods specifically designed for high-dimensional data. The aim of this study was to compare how three different statistical approaches, multifactor dimensionality reduction (MDR), random forests (RF), and an omnibus approach, worked in identifying gene effects (including gene-gene interaction) associated with RA. We developed a test set of genes based on previous linkage and association findings and tested all three methods. In the presence of the HLA shared-epitope factor, other genes showed weaker effects. All three methods detected SNPs in PTPN22 and TRAF1-C5 as being important. But we did not detect any new genes in this study. We conclude that the three high-dimensional methods are useful as an initial screening for gene associations to identify promising genes for further modeling and additional replication studies

    New records for the liverwort and hornwort flora of Vietnam, 1

    Get PDF
    After the examination of the Cryptogam collection in the Herbarium of the University of Science, Vietnam National University Ho Chi Minh City (PHH), 25 species proved to be new to Vietnam, including one hornwort and 24 liverworts. Among them, four genera: Denotarisia Grolle, Gongylanthus Nees, Leiomitra Lindb. and Lepicolea Dumort. are new records for the country. Diagnostic characters and illustrations are given for some taxa, as well as locality notes and habitat descriptions are provided for each collecting area.</p

    Rheological Properties and Age-Related Changes of the Human Vitreous Humor

    Get PDF
    The vitreous humor is a fragile, transparent hydrogel situated between the lens and the retina, occupying 80% of the eye's volume. Due to its viscoelastic behavior, the vitreous serves as a mechanical damper for the eye, absorbing impacts, and protecting the lens and retina. The vitreous liquefies with age, which compromises its function as a shock absorber and causes complications including retinal detachment, macular holes, and vitreous hemorrhage. Studies on the viscoelastic properties of the vitreous have been limited. Rheological testing of the vitreous has commonly been done on non-primate mammalian species. Human vitreous rheological properties have been previously reported; however, various measurement techniques were used, resulting in data that differed by orders of magnitude. Shear rheometry is commonly used to characterize soft tissues and hydrogels such as the vitreous humor. However, no human vitreous rheological data have been reported using this technique, preventing direct comparison to other published work. Additionally, no age-related changes in the mechanical properties of the human vitreous humor have been reported. Human vitreous samples (n = 39, aged 62 ± 15 years) were tested using a shear rheometer. Small amplitude oscillatory shear and creep experiments were performed. The linear viscoelastic region of the human vitreous was found to be below 1% strain. The solid phase of the old human vitreous was found to be stiffer than the young human vitreous and the porcine vitreous. The stiffness of the human vitreous gel also appeared to be positively correlated with age. Vitreous dehydration due to a decrease in hyaluronic acid concentration with age was proposed to cause the stiffening of the solid phase of the vitreous gel. Vitreous liquefaction, therefore, might be characterized as a simultaneous increase in liquid volume and localized stiffening of the vitreous gel. The phase separation of the vitreous humor with age has been hypothesized as the cause of many vitreous-related complications. This study provides viscoelastic properties and age-related changes of the human vitreous humor, which will aid in the design of biomimetic vitreous substitutes, enhancement in analyzing intravitreal transport of therapeutics, and understanding the pathological conditions of the vitreous humor

    Engaging stakeholders in rehabilitation research: a scoping review of strategies used in partnerships and evaluation of impacts

    Get PDF
    Abstract: Purpose: To describe how stakeholder engagement has been undertaken and evaluated in rehabilitation research. Methods: A scoping review of the scientific literature using five search strategies. Quantitative and qualitative analyses using extracted data. Interpretation of results was iteratively discussed within the team, which included a parent stakeholder. Results: Searches identified 101 candidate papers; 28 were read in full to assess eligibility and 19 were included in the review. People with disabilities and their families were more frequently involved compared to other stakeholders. Stakeholders were often involved in planning and evaluating service delivery. A key issue was identifying stakeholders; strategies used to support their involvement included creating committees, organizing meetings, clarifying roles and offering training. Communication, power sharing and resources influenced how stakeholders could be engaged in the research. Perceived outcomes of stakeholder engagement included the creation of partnerships, facilitating the research process and the application of the results, and empowering stakeholders. Stakeholder engagement outcomes were rarely formally evaluated. Conclusions: There is a great interest in rehabilitation to engage stakeholders in the research process. However, further evidence is needed to identify effective strategies for meaningful stakeholder engagement that leads to more useful research that positively impacts practice. Implications for Rehabilitation Using several strategies to engage various stakeholders throughout the research process is thought to increase the quality of the research and the rehabilitation process by developing proposals and programs responding better to their needs. Engagement strategies need to be better reported and evaluated in the literature. Engagement facilitate uptake of research findings by increasing stakeholders' awareness of the evidence, the resources available and their own ability to act upon a situation. Factors influencing opportunities for stakeholder engagement need to be better understood

    Impact of Virologic Breakthrough and HBIG Regimen on Hepatitis B Recurrence After Liver Transplantation

    Full text link
    The availability of hepatitis B immune globulin (HBIG) and several oral antiviral therapies has reduced but not eliminated hepatitis B virus (HBV) recurrence. We aimed to determine the rate of HBV recurrence after orthotopic liver transplantation (OLT) in relation to virologic breakthrough pre-OLT and HBIG regimens post-OLT. Data from the NIH HBV-OLT database were analyzed. A total of 183 patients transplanted between 2001 and 2007 followed for a median of 42 months (range 1–81) post-OLT were studied. At transplant, 29% were hepatitis B e antigen (HBeAg) (+), 38.5% had HBV DNA > 5 log 10 copies/mL, 74% were receiving antiviral therapy. Twenty-five patients experienced virologic breakthrough before OLT. Post-OLT, 26%, 22%, 40% and 12% of patients received intravenous (IV) high-dose, IV low-dose, intramuscular low-dose and a finite duration of HBIG, respectively as maintenance prophylaxis. All but two patients also received antiviral therapy. Cumulative rates of HBV recurrence at 1 and 5 years were 3% and 9%, respectively. Multivariate analysis showed that listing HBeAg status and HBV DNA level at OLT were the only factors associated with HBV recurrence. In conclusion, low rates of HBV recurrence can be accomplished with all the HBIG regimens used when combined with antiviral therapy including patients with breakthrough pre-OLT as long as rescue therapy is administered pre- and post-OLT.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79358/1/j.1600-6143.2010.03046.x.pd

    Inclusive cross section and single-transverse-spin asymmetry for very forward neutron production in polarized p+p collisions at sqrt(s)=200 GeV

    Full text link
    The energy dependence of the single-transverse-spin asymmetry, A_N, and the cross section for neutron production at very forward angles were measured in the PHENIX experiment at RHIC for polarized p+p collisions at sqrt(s)=200 GeV. The neutrons were observed in forward detectors covering an angular range of up to 2.2 mrad. We report results for neutrons with momentum fraction of x_F=0.45 to 1.0. The energy dependence of the measured cross sections were consistent with x_F scaling, compared to measurements by an ISR experiment which measured neutron production in unpolarized p+p collisions at sqrt(s)=30.6--62.7 GeV. The cross sections for large x_F neutron production for p+p collisions, as well as those in e+p collisions measured at HERA, are described by a pion exchange mechanism. The observed forward neutron asymmetries were large, reaching A_N=-0.08+/-0.02 for x_F=0.8; the measured backward asymmetries, for negative x_F, were consistent with zero. The observed asymmetry for forward neutron production is discussed within the pion exchange framework, with interference between the spin-flip amplitude due to the pion exchange and nonflip amplitudes from all Reggeon exchanges. Within the pion exchange description, the measured neutron asymmetry is sensitive to the contribution of other Reggeon exchanges even for small amplitudes.Comment: 383 authors, 16 pages, 18 figures, 6 tables. Submitted to Phys. Rev. D. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at http://www.phenix.bnl.gov/papers.htm
    corecore