5,897 research outputs found
Profiling alumni of a Brazilian public dental school
<p>Abstract</p> <p>Background</p> <p>Follow-up studies of former students are an efficient way to organize the entire process of professional training and curriculum evaluation. The aim of this study was to identify professional profile subgroups based on job-related variables in a sample of former students of a Brazilian public dental school.</p> <p>Methods</p> <p>A web-based password-protected questionnaire was sent to 633 registered dentists who graduated from the Federal University of Goias between 1988 and 2007. Job-related information was retrieved from 14 closed questions, on subjects such as gender, occupational routine, training, profits, income status, and self-perception of professional career, generating an automatic database for analysis. The two-step cluster method was used for dividing dentists into groups on the basis of minimal within-group and maximal between-group variation, using job-related variables to represent attributes upon which the clustering was based.</p> <p>Results</p> <p>There were 322 respondents (50.9%), predominantly female (64.9%) and the mean age was 34 years (SD = 6.0). The automatic selection of an optimal number of clusters included 289 cases (89.8%) in 3 natural clusters. Clusters 1, 2 and 3 included 52.2%, 30.8% and 17.0% of the sample respectively. Interpretation of within-group rank of variable importance for cluster segmentation resulted in the following characterization of clusters: Cluster 1 - specialist dentists with higher profits and positive views of the profession; Cluster 2 - general dental practitioners in small cities; Cluster 3 - underpaid and less motivated dentists with negative views of the profession. Male dentists were predominant in cluster 1 and females in cluster 3. One-way Anova showed that age and time since graduation were significantly lower in Cluster 2 (<it>P </it>< 0.001). Alternative solutions with 4 and 5 clusters revealed specific discrimination of Cluster 1 by gender and dental education professionals.</p> <p>Conclusions</p> <p>Cluster analysis was a valuable method for identifying natural grouping with relatively homogeneous cases, providing potentially meaningful information for professional orientation in dentistry in a variety of professional situations and environments.</p
Calculations of three-body observables in ^8B breakup
We discuss calculations of three-body observables for the breakup of ^8B on a
^{58}Ni target at low energy using the coupled discretised continuum channels
approach. Calculations of both the angular distribution of the ^7Be fragments
and their energy distributions are compared with those measured at several
laboratory angles. In these observables there is interference between the
breakup amplitudes from different spin-parity excitations of the projectile.
The resulting angle and the energy distributions reveal the importance of the
higher-order continuum state couplings for an understanding of the
measurements.Comment: 22 pages (postscript), accepted in Phys. Rev.
Material alternativo para confecção de filtros empregados na metodologia "Nylon bag" para a determinação de fibra.
Teores de fibra em detergente neutro (FDN) e fibra em detergente ĂĄcido (FDA) em milho, soja, farelo de trigo, capins, feno, silagens, fezes e conteĂșdo duodenal de bovinos, foram determinados em analisador de fibra ANKOM 220, empregando saquinhos de polipropileno (TNT ? Tecido NĂŁo Tecido) confeccionados no laboratĂłrio, como material alternativo aos filtros fabricados e comercializados pela ANKOM. As anĂĄlises foram conduzidas no LaboratĂłrio de Nutrição Animal da Embrapa PecuĂĄria Sudeste, SĂŁo Carlos - SP. Em um primeiro ensaio, os dois materiais foram comparados. O delineamento experimental foi inteiramente casualizado, em esquema fatorial 6 x 2 (seis amostras e dois tipos de saquinho), com trĂȘs repetiçÔes. Em um segundo ensaio, amostras de referĂȘncia foram usadas para confirmar a eficiĂȘncia dos saquinhos de TNT. Para tal, foram avaliados o efeito da massa de amostra (0,5 e 0,25 mg) nos teores de FDN e FDA e o emprego de a amilase nos resultados de FDN. O delineamento experimental foi inteiramente casualizado em esquema fatorial 5 x 4 (cinco fatores e 4 amostras), com trĂȘs repetiçÔes. NĂŁo foram observadas diferenças significativas (P > 0,05) entre os resultados obtidos com o emprego deste material em comparação aos filtros ANKOM. Os fatores variação de massa de amostra e adição de a amilase nĂŁo tiveram efeito sobre os teores de FDN e FDA (P > 0,05). O TNT apresentou caracterĂsticas favorĂĄveis e promissoras ao seu uso, como baixo custo, rigidez e baixa porosidade
Representing addition and subtraction : learning the formal conventions
The study was designed to test the effects of a structured intervention in teaching children to represent addition and subtraction. In a post-test only control group design, 90 five-year-olds experienced the intervention entitled Bi-directional Translation whilst 90 control subjects experienced typical teaching. Post-intervention testing showed some significant differences between the two groups both in terms of being able to effect the addition and subtraction operations and in being able to determine which operation was appropriate. The results suggest that, contrary to historical practices, children's exploration of real world situations should precede practice in arithmetical symbol manipulation
Testing nonperturbative techniques in the scalar sector of the standard model
We discuss the current picture of the standard model's scalar sector at
strong coupling. We compare the pattern observed in the scalar sector in
perturbation theory up to two-loop with the nonperturbative solution obtained
by a next-to-leading order 1/N expansion. In particular, we analyze two
resonant Higgs scattering processes, ff -> H -> f'f' and ff -> H -> ZZ, WW. We
describe the ingredients of the nonperturbative calculation, such as the
tachyonic regularization, the higher order 1/N intermediate renormalization,
and the numerical methods for evaluating the graphs.
We discuss briefly the perspectives and usefulness of extending these
nonperturbative methods to other theories
Structural and spatially-resolved studies on the hardening of a commercial resin-modified glass-ionomer cement
A commercial photopolymerizable resinmodified glass-ionomer (Fuji II LC) was studied using a variety of nuclear magnetic resonance (NMR) techniques. H and F stray-field imaging (STRAFI) enabled to follow the acidâbase reaction kinetics in self-cured (SC) samples. Gelation and maturation processes with 25 min and 40 h average time constants, respectively, were distinguished. In self- & photo-cured (SPC) samples, two processes were also observed, which occurred with 2 s and 47 s average time constants. H, Al and Si magic angle spinning (MAS) NMR, C cross-polarization (CP)/MAS NMR and 27Al multiple quanta (MQ)MAS NMR spectroscopy were used to obtain structural information on the glass and cements that were either SC or SPC. The presence of methacrylate groups was identified in the solid component. Unreacted hydroxyl ethylmethacrylate (HEMA) was detected in self-cured cement. Al data showed that approximately 28% and 20% of Al is leached out from glass particles in SC and SPC samples, respectively. The upfield shift detected in 25Si MAS NMR spectra of the cements is consistent with a decrease in the number of Al species in the second coordination sphere of the silicon structures. Scanning electron microscopy (SEM) showed existence of 3D shrinkage of the cement matrix in photo-cured cements.(undefined
Coulomb and nuclear breakup of B
The cross sections for the (B,Be-) breakup reaction on Ni
and Pb targets at the beam energies of 25.8 MeV and 415 MeV have been
calculated within a one-step prior-form distorted-wave Born approximation. The
relative contributions of Coulomb and nuclear breakup of dipole and quadrupole
multipolarities as well as their interference have been determined. The nuclear
breakup contributions are found to be substantial in the angular distributions
of the Be fragment for angles in the range of 30 - 80 at
25.8 MeV beam energy. The Coulomb-nuclear interference terms make the dipole
cross section larger than that of quadrupole even at this low beam energy.
However, at the incident energy of 415 MeV, these effects are almost negligible
in the angular distributions of the (Be-p) coincidence cross sections at
angles below 4.Comment: Revised version, accepted for publication in Phys. Rev.
Caracterização agronĂŽmica e seleção de hĂbridos para o desenvolvimento de novas cultivares de uvas sem sementes para o SemiĂĄrido brasileiro.
O objetivo deste trabalho foi avaliar e selecionar hĂbridos procedentes de cruzamentos do programa de de melhoramento de uva sem sementes da Embrapa SemiĂĄrido
Produção de plùntulas in vitro a partir de diferentes explantes de sementes de camu-camu (Myrciaria dubia (H.B.K.) Mc vaugh).
Vine performance and physicochemical characteristics of berries of new wine grape cultivars in the SĂŁo Francisco Valley.
This study aimed to evaluate the performance and characteristics of the grapes as subsidies to the recommendation of new wine grape cultivars for the SĂŁo Francisco Valley
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