925 research outputs found

    Oral Cancer Awareness and its Determinants among a Selected Malaysian Population

    Get PDF
    Objective: To assess oral cancer awareness, its associated factors and related sources of information among a selected group of Malaysians. Methods: A cross-sectional survey was conducted on all Malaysian ethnic groups aged >= 15 years old at eight strategically chosen shopping malls within a two week time period. Data were analysed using chi-square tests and multiple logistic regression. Significance level was set at alpha<0.05. Results: Most (84.2%) respondents had heard of oral cancer. Smoking was the most (92.4%) recognized high risk habit. Similar levels of awareness were seen for unhealed ulcers (57.3%) and red/white patches (58.0%) as signs of oral cancer. Age, gender, ethnicity, marital status, education, occupation and income were significantly associated with oral cancer awareness (p<0.05). Conclusions: There was a general lack of awareness regarding the risk habits, early signs and symptoms, and the benefits of detecting this disease at an early stage. Mass media and health campaigns were the main sources of information about oral cancer. In our Malaysian population, gender and age were significantly associated with the awareness of early signs and symptoms and prevention of oral cancer, respectively.Article Link: http://koreascience.or.kr/article/ArticleFullRecord.jsp?cn=POCPA9_2013_v14n3_195

    Fragment Flow and the Nuclear Equation of State

    Full text link
    We use the Boltzmann-Uehling-Uhlenbeck model with a momentum-dependent nuclear mean field to simulate the dynamical evolution of heavy ion collisions. We re-examine the azimuthal anisotropy observable, proposed as sensitive to the equation of state of nuclear matter. We obtain that this sensitivity is maximal when the azimuthal anisotropy is calculated for nuclear composite fragments, in agreement with some previous calculations. As a test case we concentrate on semi-central 197Au + 197Au^{197}{\rm Au}\ +\ ^{197}{\rm Au} collisions at 400 AA MeV.Comment: 12 pages, ReVTeX 3.0. 12 Postscript figures, uuencoded and appende

    Maximum Azimuthal Anisotropy of Neutrons from Nb-Nb Collisions at 400 AMeV and the Nuclear Equation of State

    Get PDF
    We measured the first azimuthal distributions of triple--differential cross sections of neutrons emitted in heavy-ion collisions, and compared their maximum azimuthal anisotropy ratios with Boltzmann--Uehling--Uhlenbeck (BUU) calculations with a momentum-dependent interaction. The BUU calculations agree with the triple- and double-differential cross sections for positive rapidity neutrons emitted at polar angles from 7 to 27 degrees; however, the maximum azimuthal anisotropy ratio for these free neutrons is insensitive to the size of the nuclear incompressibility modulus K characterizing the nuclear matter equation of state.Comment: Typeset using ReVTeX, with 3 ps figs., uuencoded and appende

    Neutrons from multiplicity-selected La-La and Nb-Nb collisions at 400A MeV and La-La collisions at 250A MeV

    Full text link
    Triple-differential cross sections for neutrons from high-multiplicity La-La collisions at 250 and 400 MeV per nucleon and Nb-Nb collisions at 400 MeV per nucleon were measured at several polar angles as a function of the azimuthal angle with respect to the reaction plane of the collision. The reaction plane was determined by a transverse-velocity method with the capability of identifying charged-particles with Z=1, Z=2, and Z > 2. The flow of neutrons was extracted from the slope at mid-rapidity of the curve of the average in-plane momentum vs the center-of-mass rapidity. The squeeze-out of the participant neutrons was observed in a direction normal to the reaction plane in the normalized momentum coordinates in the center-of-mass system. Experimental results of the neutron squeeze-out were compared with BUU calculations. The polar-angle dependence of the maximum azimuthal anisotropy ratio r(Ξ)r(\theta) was found to be insensitive to the mass of the colliding nuclei and the beam energy. Comparison of the observed polar-angle dependence of the maximum azimuthal anisotropy ratio r(Ξ)r(\theta) with BUU calculations for free neutrons revealed that r(Ξ)r(\theta) is insensitive also to the incompressibility modulus in the nuclear equation of state.Comment: ReVTeX, 16 pages, 17 figures. To be published in Physical Review

    The importance of initial-final state correlations for the formation of fragments in heavy ion collisions

    Get PDF
    Using quantum molecular dynamics simulations, we investigate the formation of fragments in symmetric reactions between beam energies of E=30AMeV and 600AMeV. After a comparison with existing data we investigate some observables relevant to tackle equilibration: dsigma/dErat, the double differential cross section dsigma/pt.dpz.dpt,... Apart maybe from very energetic E>400AMeV and very central reactions, none of our simulations gives evidence that the system passes through a state of equilibrium. Later, we address the production mechanisms and find that, whatever the energy, nucleons finally entrained in a fragment exhibit strong initial-final state correlations, in coordinate as well as in momentum space. At high energy those correlations resemble the ones obtained in the participant-spectator model. At low energy the correlations are equally strong, but more complicated; they are a consequence of the Pauli blocking of the nucleon-nucleon collisions, the geometry, and the excitation energy. Studying a second set of time-dependent variables (radii, densities,...), we investigate in details how those correlations survive the reaction especially in central reactions where the nucleons have to pass through the whole system. It appears that some fragments are made of nucleons which were initially correlated, whereas others are formed by nucleons scattered during the reaction into the vicinity of a group of previously correlated nucleons.Comment: 45 pages text + 20 postscript figures Accepted for publication in Physical Review

    Neutrons from multiplicity-selected Au-Au collisions at 150, 250, 400, and 650 AMeV

    Full text link
    We measured neutron triple-differential cross sections from multiplicity-selected Au-Au collisions at 150, 250, 400, and 650 \AMeV. The reaction plane for each collision was estimated from the summed transverse velocity vector of the charged fragments emitted in the collision. We examined the azimuthal distribution of the triple-differential cross sections as a function of the polar angle and the neutron rapidity. We extracted the average in--plane transverse momentum ⟹Px⟩\langle P_x\rangle and the normalized observable ⟹Px/P⊄⟩\langle P_x/P_\perp\rangle, where P⊄P_\perp is the neutron transverse momentum, as a function of the neutron center-of-mass rapidity, and we examined the dependence of these observables on beam energy. These collective flow observables for neutrons, which are consistent with those of protons plus bound nucleons from the Plastic Ball Group, agree with the Boltzmann--Uehling--Uhlenbeck (BUU) calculations with a momentum--dependent interaction. Also, we calculated the polar-angle-integrated maximum azimuthal anisotropy ratio R from the value of ⟹Px/P⊄⟩\langle P_x/P_\perp\rangle.Comment: 20 LaTeX pages. 11 figures to be faxed on request, send email to sender's addres

    Radial Flow in Au+Au Collisions at E=0.25-1.15 A GeV

    Get PDF
    A systematic study of energy spectra for light particles emitted at midrapidity from Au+Au collisions at E=0.25-1.15 A GeV reveals a significant non-thermal component consistent with a collective radial flow. This component is evaluated as a function of bombarding energy and event centrality. Comparisons to Quantum Molecular Dynamics (QMD) and Boltzmann-Uehling-Uhlenbeck (BUU) models are made for different equations of state.Comment: 10 pages of text and 4 figures (all ps files in a uuencoded package)

    Influence of Surface Properties and Impact Conditions on Adhesion of Insect Residues

    Get PDF
    Insect residues can cause premature transition to turbulent flow on laminar flow airfoils. Engineered surfaces that mitigate the adhesion of insect residues provide, therefore, a route to more efficient aerodynamics and reduced fuel burn rates. Areal coverage and heights of residues depend not only on surface properties, but also on impact conditions. We report high speed photography of fruit fly impacts at different angles of inclination on a rigid aluminum surface, optical microscopy and profilometry, and contact angle goniometry to support the design of engineered surfaces. For the polyurethane and epoxy coatings studied, some of which exhibited superhydrophobicity, it was determined that impact angle and surface compositions play critical roles in the efficacy of these surfaces to reduce insect residue adhesion

    Higher Levels of Income and Education are Associated with More Specialized Sport Participation Behaviors: Results from a Representative Sample of Youth Sport Parents from the United States

    Get PDF
    # Background While previous studies have examined the impact of family socioeconomic characteristics on a child's sport specialization behaviors, this research has been limited to affluent communities with limited sociodemographic diversity. # Hypothesis/Purpose The purpose of this study was to examine associations of parent income and education with child sport specialization behaviors among a nationally representative sample of youth sport parents in the United States. # Study Design Cross-sectional. # Methods Parents of youth athletes in the United States (n=236, age: 39.2±8.1 years, 57.2% female) were recruited to complete an online questionnaire by Qualtrics Online Samples (Qualtrics, Provo, UT) using a combination of actively managed, double-opt-in market research panels. The questionnaire used for this study consisted of: 1) parent demographics (including parent age, race/ethnicity, biological sex, gender identity, household income, and educational status), and 2) child sport participation characteristics and sport specialization behaviors. # Results Parents who reported an annual household income of \$75,001 or more were more likely than parents making less than \$75,000 to report that their child participated on an organized club team (OR 9595%CI: 1.94 1.15−3.271.15-3.27), participated on multiple organized teams at the same time (OR 9595%CI: 1.85 1.10−3.111.10-3.11), or specialized in a single sport (OR 9595%CI: 2.45 1.45−4.141.45-4.14). Parents who reported receiving a Bachelor's degree or higher were more likely than parents who did not to report that their child participated on an organized club team (OR 9595%CI: 3.04 1.78−5.181.78-5.18), participated on multiple organized teams at the same time (OR 9595%CI: 2.42 1.43−4.101.43-4.10), or specialized in a single sport (OR 9595%CI: 1.94 1.15−3.261.15-3.26). # Conclusions Thes results suggest that in the modern youth sport culture, family resources may serve as a major determining factor in the type of experiences available for a youth athlete. # Level of Evidence II
    • 

    corecore