2,100 research outputs found
Perceived orientation, spatial layout and the geometry of pictures
The purpose is to discuss the role of geometry in determining the perception of spatial layout and perceived orientation in pictures viewed at an angle. This discussion derives from Cutting's (1988) suggestion, based on his analysis of some of the author's data (Goldstein, 1987), that the changes in perceived orientation that occur when pictures are viewed at an angle can be explained in terms of geometrically produced changes in the picture's virtual space
Toward understanding male flutists in public schools: a qualitative study
Thesis (D.M.A.)--Boston UniversityResearch has suggested that musical instruments are not only gender-stereotyped, but the association of the flute with femininity, in particular, is still quite strong. The prospect of boys playing the flute has remained controversial among public school students. In this qualitative collective case study, male flute students were examined through interview and observation. This research focused on the initial factors that encouraged these students to begin playing the flute and subsequently investigated how and why the students chose to continue or discontinue playing the instrument. Elements of each student's background were investigated, including: family, peers, school environment, and social and personal interpretations of masculinity in modern society.
Participants were interviewed to the point of data saturation. Eight boys were interviewed: four current and four former flutists. Part of the research focus was also on students' personal characteristics and how they may relate to each student's continuing or discontinuing playing the instrument. Students were interviewed using a pre-planned interview guide and interviews were triangulated with observations in a school music classroom situation if the boy still participated, or another academic classroom if the boy did not still participate. Descriptive narratives were written about each boy to complete data analysis. A cross-case analysis developed to interpret the data.
This study found personal and social factors that influence boys' success in playing the flute in the public school environment, including: personality, age, presence of other boys, the instrument selection process, adult support, peer reactions, and social groups. The conclusions of this study provided insight on musical instrument gender stereotyping and the instrument selection process as boys attempted to cross the boundaries on what has been portrayed as the most controversial of the gender stereotyped instruments. This study suggested that the flute was still strongly female gender-stereotyped, the instrument selection process played an important role in the memories of high school boys, boys received more harassment about the flute being a girls' instrument than other forms of harassment, boys who were the only flutist in their school or band felt lonely, and boys who shared the flute-playing experience with other boys formed fast bonds between themselves. Questions were raised about the best age to start the instrument selection process, the age during which students determine instrumental music continuation, and the role students and instruments play together in forming a musical voice. These conclusions were applied to help music educators as they continue to address these stereotypes with future students and help students choose instruments upon which they will find musical success while maintaining a quality music program
Critical Point Field Mixing in an Asymmetric Lattice Gas Model
The field mixing that manifests broken particle-hole symmetry is studied for
a 2-D asymmetric lattice gas model having tunable field mixing properties.
Monte Carlo simulations within the grand canonical ensemble are used to obtain
the critical density distribution for different degrees of particle-hole
asymmetry. Except in the special case when this asymmetry vanishes, the density
distributions exhibit an antisymmetric correction to the limiting
scale-invariant form. The presence of this correction reflects the mixing of
the critical energy density into the ordering operator. Its functional form is
found to be in excellent agreement with that predicted by the mixed-field
finite-size-scaling theory of Bruce and Wilding. A computational procedure for
measuring the significant field mixing parameter is also described, and its
accuracy gauged by comparing the results with exact values obtained
analytically.Comment: 10 Pages, LaTeX + 8 figures available from author on request, To
appear in Z. Phys.
Results at 24 months from the prospective, randomized, multicenter Investigational Device Exemption trial of ProDisc-C versus anterior cervical discectomy and fusion with 4-year follow-up and continued access patients.
BackgroundCervical total disk replacement (TDR) is intended to address pain and preserve motion between vertebral bodies in patients with symptomatic cervical disk disease. Two-year follow-up for the ProDisc-C (Synthes USA Products, LLC, West Chester, Pennsylvania) TDR clinical trial showed non-inferiority versus anterior cervical discectomy and fusion (ACDF), showing superiority in many clinical outcomes. We present the 4-year interim follow-up results.MethodsPatients were randomized (1:1) to ProDisc-C (PDC-R) or ACDF. Patients were assessed preoperatively, and postoperatively at 6 weeks and 3, 6, 12, 18, 24, 36, and 48 months. After the randomized portion, continued access (CA) patients also underwent ProDisc-C implantation, with follow-up visits up to 24 months. Evaluations included Neck Disability Index (NDI), Visual Analog Scale (VAS) for pain/satisfaction, and radiographic and physical/neurologic examinations.ResultsRandomized patients (103 PDC-R and 106 ACDF) and 136 CA patients were treated at 13 sites. VAS pain and NDI score improvements from baseline were significant for all patients (P < .0001) but did not differ among groups. VAS satisfaction was higher at all time points for PDC-R versus ACDF patients (P = .0499 at 48 months). The percentage of patients who responded yes to surgery again was 85.6% at 24 months and 88.9% at 48 months in the PDC-R group, 80.9% at 24 months and 81.0% at 48 months in the ACDF group, and 86.3% at 24 months in the CA group. Five PDC-R patients (48 months) and no CA patients (24 months) had index-level bridging bone. By 48 months, approximately 4-fold more ACDF patients required secondary surgery (3 of 103 PDC-R patients [2.9%] vs 12 of 106 ACDF patients [11.3%], P = .0292). Of these, 6 ACDF patients (5.6%) required procedures at adjacent levels. Three CA patients required secondary procedures (24 months).ConclusionsOur 4-year data support that ProDisc-C TDR and ACDF are viable surgical options for symptomatic cervical disk disease. Although ACDF patients may be at higher risk for additional surgical intervention, patients in both groups show good clinical results at longer-term follow-up
Kinesin-II is required for axonal transport of choline acetyltransferase in Drosophila
KLP64D and KLP68D are members of the kinesin-II family of proteins in Drosophila. Immunostaining for KLP68D and ribonucleic acid in situ hybridization for KLP64D demonstrated their preferential expression in cholinergic neurons. KLP68D was also found to accumulate in cholinergic neurons in axonal obstructions caused by the loss of kinesin light chain. Mutations in the KLP64D gene cause uncoordinated sluggish movement and death, and reduce transport of choline acetyltransferase from cell bodies to the synapse. The inviability of KLP64D mutations can be rescued by expression of mammalian KIF3A. Together, these data suggest that kinesin-II is required for the axonal transport of a soluble enzyme, choline acetyltransferase. in a specific subset of neurons in Drosophila. Furthermore, the data lead to the conclusion that the cargo transport requirements of different classes of neurons may lead to upregulation of specific pathways of axonal transport
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