314 research outputs found
Spor Yapan Çocukların Spor Tercihleri Ve Bunu Etkileyen Bazı Faktörlerin İncelenmesi,
Araştırmanın amacı spor yapan öğrencilerin spor yapma tercihlerini belirleyen faktörlerin belirlenmesi ve bazı faktörler arasındaki ilişkinin incelenmesidir. Araştırma uygulamalı bir çalışma olup, ölçekli bir anket formu kullanılmıştır. Uygulamada kullanılan anket daha önce kullanılmış ve güvenirliliği sağlanmış bir anket olup, anket üzerinde bazı değişiklikler gerçekleştirilmiştir. Araştırmanın örneklemini rast gele yöntemle seçilmiş olan 3562 katılımcı oluşturmaktadır. Katılımcılara (N= 3562) uygulanan anketin güvenirlik katsayısı (Cronbach’s Alpha) hesaplanarak 0.950 değeri elde edilmiştir. Bireyden elde edilen veriler SPSS Pasw 18.0 istatistik programı ile analiz edilmiştir. Araştırma 19 ay sürmüştür. Araştırmada kullanılan teknik basit rassal yöntemdir. Araştırmada betimleyici istatistikler, faktör analizi, KMO ve Barlett’s testi, eşleştirilmiş iki grup t-testi, bağımsız t- testi, Crosstabs testi ve Anova testlerinden yararlanılmıştır. Araştırma sonunda anne-baba eğitim durumu, gelir durumu, spor yapılan mekanın spor tercihine etki ettiği bulunmuştur. Aynı zamanda ebeveyn eğitimi, çalışma durumu ve Tv ve görsel araçların çocuğun beslenme alışkanlıklarında, beslenme alışkanlığının ise psikolojik durum ve spor yaralanmalarında etken faktör olduğu saptanmıştır
Pressure-Induced Interlinking of Carbon Nanotubes
We predict new forms of carbon consisting of one and two dimensional networks
of interlinked single wall carbon nanotubes, some of which are energetically
more stable than van der Waals packing of the nanotubes on a hexagonal lattice.
These interlinked nanotubes are further transformed with higher applied
external pressures to more dense and complicated stable structures, in which
curvature-induced carbon sp re-hybridizations are formed. We also discuss
the energetics of the bond formation between nanotubes and the electronic
properties of these predicted novel structures.Comment: 4 pages, 4 postscript figures; To be appear in PR
Turkish Validity and Reliability Study of the Speech, Spatial and Qualities of Hearing Scale
Objective:The Speech, Spatial and Qualities of Hearing Scale (SSQ) is a self-report scale that evaluates hearing in complex daily life situations in the areas of hearing quality, speech perception, and spatial perception. It is also frequently used in the follow-up of hearing-impaired people, hearing aid and cochlear implant users. It is aimed to translate and adapt SSQ into Turkish, and to investigate its test-retest reliability, and construct validity and reliability, and further to present associations of SSQ scores with the pure tone averages (PTA).Methods:The Turkish SSQ (Tr-SSQ) scale was administered on 114 adults including those with and without hearing loss. Cronbach’s alpha was used to assess its reliability. The reliability coefficient of the scale was calculated by test-retest method. Associations of SSQ scores with PTAs in better and worse hearing ears (BHE and WHE) were evaluated.Results:Tr-SSQ presented high internal consistency (Cronbach’s alpha = 0.984) and test-retest reliability (r=0.994). Tr-SSQ scores were lower in the subjects with hearing loss and correlated with PTAs. Age was found to be correlated with PTAs; regression analysis demonstrated that only WHE-PTA was extracted as explanatory variable for average Tr-SSQ, speech perception and spatial perception scores while both BHE-PTA and WHE-PTA were found to be predictors of hearing quality, but not age for any of Tr-SSQ scores.Conclusion:Tr-SSQ is a convenient tool for assessing the hearing abilities of individuals with hearing impaired
Quantum point contact on graphite surface
The conductance through a quantum point contact created by a sharp and hard
metal tip on the graphite surface has features which to our knowledge have not
been encountered so far in metal contacts or in nanowires. In this paper we
first investigate these features which emerge from the strongly directional
bonding and electronic structure of graphite, and provide a theoretical
understanding for the electronic conduction through quantum point contacts. Our
study involves the molecular-dynamics simulations to reveal the variation of
interlayer distances and atomic structure at the proximity of the contact that
evolves by the tip pressing toward the surface. The effects of the elastic
deformation on the electronic structure, state density at the Fermi level, and
crystal potential are analyzed by performing self-consistent-field
pseudopotential calculations within the local-density approximation. It is
found that the metallicity of graphite increases under the uniaxial compressive
strain perpendicular to the basal plane. The quantum point contact is modeled
by a constriction with a realistic potential. The conductance is calculated by
representing the current transporting states in Laue representation, and the
variation of conductance with the evolution of contact is explained by taking
the characteristic features of graphite into account. It is shown that the
sequential puncturing of the layers characterizes the conductance.Comment: LaTeX, 11 pages, 9 figures (included), to be published in Phys. Rev.
B, tentatively scheduled for 15 September 1998 (Volume 58, Number 12
Atrioventricular thrombus in a 14-year-old patient: a case report
Right atrioventricular thrombus was diagnosed by echocardiography in a 14-year-old boy. Thrombus was reached through the right ventricle to the pulmonary artery and it was caused to tricuspit valve insufficiency. Surgical thrombectomy was performed and, he was treated with oral anticoagulation in postoperative period
Gas-phase composition and secondary organic aerosol formation from standard and particle filter-retrofitted gasoline direct injection vehicles investigated in a batch and flow reactor
Gasoline direct injection (GDI) vehicles have recently been identified as a
significant source of carbonaceous aerosol, of both primary and secondary
origin. Here we investigated primary emissions and secondary organic aerosol
(SOA) from four GDI vehicles, two of which were also retrofitted with a
prototype gasoline particulate filter (GPF). We studied two driving test
cycles under cold- and hot-engine conditions. Emissions were characterized by
proton transfer reaction time-of-flight mass spectrometry (gaseous
non-methane organic compounds, NMOCs), aerosol mass spectrometry (sub-micron
non-refractory particles) and light attenuation measurements (equivalent
black carbon (eBC) determination using Aethalometers) together with
supporting instrumentation. Atmospheric processing was simulated using the
PSI mobile smog chamber (SC) and the potential aerosol mass oxidation flow
reactor (OFR). Overall, primary and secondary particulate matter (PM) and
NMOC emissions were dominated by the engine cold start, i.e., before thermal
activation of the catalytic after-treatment system. Trends in the
SOA oxygen to carbon ratio (O : C) for OFR and SC were
related to different OH exposures, but divergences in the H : C remained
unexplained. SOA yields agreed within experimental variability between the
two systems, with a tendency for higher values in the OFR than in the SC (or,
vice versa, lower values in the SC). A few aromatic compounds dominated the
NMOC emissions, primarily benzene, toluene, xylene isomers/ethylbenzene and
C3-benzene. A significant fraction of the SOA was explained by those
compounds, based on comparison of effective SOA yield curves with those of
toluene, o-xylene and 1,2,4-trimethylbenzene determined in our OFR, as well
as others from literature. Remaining discrepancies, which were smaller in the
SC and larger in the OFR, were up to a factor of 2 and may have resulted from
diverse reasons including unaccounted precursors and matrix effects. GPF
retrofitting significantly reduced primary PM through removal of refractory
eBC and partially removed the minor POA fraction. At cold-started conditions
it did not affect hydrocarbon emission factors, relative chemical composition
of NMOCs or SOA formation, and likewise SOA yields and bulk composition
remained unaffected. GPF-induced effects at hot-engine conditions
deserve attention in further studies.</p
Mechanical forces induce an asthma gene signature in healthy airway epithelial cells
Bronchospasm compresses the bronchial epithelium, and this compressive stress has been implicated in asthma pathogenesis. However, the molecular mechanisms by which this compressive stress alters pathways relevant to disease are not well understood. Using air-liquid interface cultures of primary human bronchial epithelial cells derived from non-asthmatic donors and asthmatic donors, we applied a compressive stress and then used a network approach to map resulting changes in the molecular interactome. In cells from non-asthmatic donors, compression by itself was sufficient to induce inflammatory, late repair, and fibrotic pathways. Remarkably, this molecular profile of non-asthmatic cells after compression recapitulated the profile of asthmatic cells before compression. Together, these results show that even in the absence of any inflammatory stimulus, mechanical compression alone is sufficient to induce an asthma-like molecular signature
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